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motion-at005 - Rockwell Automation

1. 109 Block D 7000 Kinetix 6000 Kinetix 6200 and Kinetix 2000 drive control loop architecture is shown in the following diagram Kinetix Sercos Drives guueu 9JEMpIeH aS120 peqpa peqpaa xny uosod ven ae 1030 auue RM 9JeMpIeH y UN 101 DJH 10117 peqpaa J03e1623U ssed M0 J03e1623U uonisod fauejod DOJA UOINSOd non peqpaa4 Joje nuJmooy Jojejnuuno y 1014 peqpaeeJ puewwo 1 ydwy J83 H M dwo pules oa amp 3 ules Joje odJa1u anbio UD ON e Pu anbio BURG d 0d 10117 oul o in ai pueunuo PORA fapoJaA Td E o anbio UOINSOd 220y yw Mg Mg ua Miu ules J0 e 0d19 U anbJo U 3oN ssed M0 1 dd PA oul4 951807 DaN so indino jnding Peat 150 2A ules JOSHO DOJA Rockwell Automation Publication MOTION AT005B EN P November 2015 Kinetix 6500 Kinetix 5500 and Kinetix 350 drive position loop architecture is shown in the following diagram Position Loop Block Diagrams EtherNet IP Drives Appendix E uohisoq CpeqpeeJ 103 35 peqpaa4 UOInISOg uonisog peqpe j oney Hun peqpaaj apo yeqpae4 SZ peqpaay peqnaay Joyesbayuy jeng COpeqpesj Cpeqpasj peqpse4 enq COpeqpesj Cpeqpasj eqp2 peo peqpaa4 papas peqpesj L peqpeej eqpa2 1010 je16ou eqpee g4 ledbayu gjuoniog APO eqpae UOnISOq UonISOd jnding Ud IISOd peo aJg 40 e1H9 U ndino Ilo 0 pjop 103e1691u dd pueuluo vus 9 Q y x UOIISOd wend 1043 dUaIaJa
2. Waiting for trigger Seton Top After autotune completes successfully the servo drive has relatively good performance If you require better performance follow these steps to manually tune the Kinetix 300 drive 1 If possible generate a bidirectional index command to the drive to test out the gains You can make manual adjustments to the gain values from the Dynamics tab The index can be unidirectional if the load cannot have bidirectional movement 2 For steps 3 and 4 disable the drive before making any changes Gain changes with the drive enabled can cause the motor to go unstable Rockwell Automation Publication MOTION AT005B EN P November 2015 Kinetix 300 Drive Tuning Chapter 6 3 Change the Gain Scaling value Using this value is similar to changing the system bandwidth described in previous sections with EtherNet IP drives The Gain Scaling is an integer and is set knowing these factors e Every integer increase the Gain Scaling value is negative effectively doubles the system bandwidth e Every integer decrease halves the system bandwidth 4 If the drive is in position mode use the Velocity Integrator or Position Integrator to improve tracking error Start with a small amount and increase it while monitoring the velocity for P p overshoot and stability A good starting point is 296 of the Ky or Kop gains 5 Increase the index speed acceleration and deceleration to meet the a
3. 2 08 13 503 PM 2 08 15 603 PM Increase the dynamics of the move profile for example increase Time Scaling and Distance Scaling in an MATC or other move instruction to generate a more aggressive move profile that approaches the dynamic and travel limits of your application Repeat steps 8 11 See Table 11 on page 45 to determine if setting other velocity loop gains are required for your application e Foran EtherNet IP drive a typical range of values for various gains are given 0x Kg x 100 0 lt K lt Kyy 4 e ForaSercos drive a typical range of values for various gains are given Note that many Sercos applications do not benefit from the use of acceleration feed forward and K should remain equal to zero 0 K g x 100 0 Kj K 4000 Stop the trend Stop the drive with an MAS instruction or motion direct command Disable the drive with an MSF instruction or motion direct command Restore the position and feed forward gains with the original values noted in step 3a to re enable the position loop Tune the Position Loop Follow these steps to manually tune the position loop after tuning the velocity loop in the previous section l Go online with the controller and have the drive in a Ready state 2 Execute motion a Enable the drive with an MSO instruction or motion direct command IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have safeguards in p
4. E Background color Pens Tab The Pens tab is the most important tab in the trend properties dialog box You need to select the correct pens to use in your trend Click Add Configure Tags to add and remove pens Sercos Drives Typical pens used in tuning a Sercos drive are shown below Name General Display Pens X Axis Y Asis Template Sampling Start Trigger Pen Attributes AxisO Commandvelocity O4 xis Axis PositionE mor SES TaqueFesdback m Axis VelocityE mot Some of these values show zero if they are not set as real time attributes Select the parameters as shown below Axis Properties Axis0 Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Cony Amplifier Catalog Number 2083ACO5 MP1 Motor Catalog Number TL A110P Hxx2 Loop Configuration Position Servo Drive Resolution 200000 Drive Counts Motor Rev v f Calculate Drive Enable Input Checking Drive Enable Input Fault Real Time Axis Information Attribute 1 Position Enor y Attribute 2 Torque Feedback Rockwell Automation Publication MOTION AT005B EN P November 2015 y Motion Groups 2 S XD Axis 3 Add On Instructions 3 Data Types Cg User Defined E Strings C Add On Defined H Ci Predefined xg Module Defined E Tren
5. 133782 7765 9 12 03 003 4M A 00 00 00 143 Command velocity 15 7766 13 9782 E PositionError 0 0526 0 0466 9 9258 EM Axis VelocityError 26 2943 23 2970 EE CurrentFeedback 52 5886 48 5940 3 8747 To clear the value bar and return to normal right click inside the trend window and choose Delta from the Active Value Bar Then check value bar again Rockwell Automation Publication MOTION AT005B EN P November 2015 101 AppendixB Creating Trends for Tuning Notes 102 Rockwell Automation Publication MOTION AT005B EN P November 2015 Setting Load Observer Configuration Attribute Appendix C Setting Sercos Gains with IDN Write Messages This appendix describes how to set Sercos gains with write messages Write the load observer configuration attribute and load observer gains each time the drive gets initialized after applying power Use the Logix Designer application to perform the Sercos IDN read and write instructions 1 After initializing the drive read the INT value of the load observer configuration with Sercos IDN P 0 431 pre Configuration IDH Read ES Conhguration Communication Tag Service lat Destmation Drmve Head Data pun Data l hd Identification gt n 7 J New Tag gemino si ul E o ET ET ow s Nd Element 7 Operation Value DalaType INT Q Enable QOEnableWal ng Stat D Done Done Length 0 2 E
6. For Kinetix 5500 and Kinetix 5700 drives choose Tracking Notch Filter from the Adaptive Tuning Configuration pull down menu on the Compliance tab in the Axis Properties dialog box For Kinetix 6500 drives if an audible noise exists at any time while tuning use a smart phone app to identify resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to manually tune out resonant frequencies h Stop the trend i Stop the drive with an MAS instruction or motion direct command j Disable the drive with an MSF instruction or motion direct command 6 Click the Manual Tune button in the low left corner of the Axis Properties dialog box o vas Manual Tune Cancel Apr Help 56 Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 Similar to the Sercos Tune Results box you can increase or decrease the System Bandwidth slider to recalculate the gains with higher or lower values based on the autotune rules Rigid loads typically require little to no adjustment of System Bandwidth and compliant loads typically require an increase in System Bandwidth to dial in the performance Figure 50 System Bandwidth Gain Calculation d A 47 47 7 Repeat step 5 to test performance while adjusting the System Bandwidth slider until you achieve the highest performance within application requirements where the Torque Refe
7. Motor Model Configuration Load Observer with Velocity Estimate Parameters F k Motor Feedback Bandwidth 311 51495 Hertz Scaling Hookup Tests Integrator Bandwidth 0 0 Hertz Polarity Autotune Load Backlash Compliance Friction Gains are limited to 500 Hz in Kinetix 6500 drive firmware revision 2 16 and earlier In Kinetix 6500 drive firmware revision 2 17 and later the gain limits are increased to 10 430 Hz For more information on how to tune the load observer see Out of Box Tuning on page 33 and Autotuning on page 43 The following table summarizes the primary difference between the two tuning modes Table 7 EtherNet IP Load Observer Tuning Mode Differences Tuning Mode Description Hz Out of box or unknown load Load Ratio 0 Load Observer Bandwidth Kp 4 x Velocity Loop Bandwidth K Autotuning or known load Load Ratio gt 0 Load Observer Bandwidth Kop Velocity Loop Bandwidth Kp Rockwell Automation Publication MOTION AT005B EN P November 2015 23 Chapter1 Background Adaptive Tuning Feature 24 This section applies to the adaptive tuning feature in Kinetix 5500 and Kinetix 5700 drives The adaptive tuning feature is an algorithm inside the drive that continuously monitors and if necessary adjusts or adapts various filter parameters and control loop gains to compensate for unknown and changing load conditions while the drive is running Its primary function is to e Automatically
8. Tag Maximum Speed 7L 833335 Position Unitas Manual Adjust Maximum Acceleration 14025 113 Position Units s 2 Maximum Deceleration 14025 113 Position Units s 2 Maximum Acceleration Jerk 2 5334 8 Position Units s 3 100 of Max Accel Time Maximum Deceleration Jerk 2 5334 8 Position Units s 3 100 of Max Decel Time wi 36 Rockwell Automation Publication MOTION AT005B EN P November 2015 EtherNet IP Drives Out of BoxTuning Chapter 2 The following sections provide information for out of box tuning of EtherNet IP drives Gain Calculation When the load ratio is set to zero in the Logix Designer application but the actual load ratio R is non zero the torque scalar is lower than what is required by the servo system and must be increased by a factor of R 1 This load disconnect has the following effects e The effectiveness of the acceleration feed forward that is applied is reduced with respect to the K gvalue entered in the Logix Designer application e The torque scalar steals a factor of R 1 from Kb lowering the actual velocity loop bandwidth by a factor of R 1 with respect to the Kp value entered in the Logix Designer application Reducing Kip causes the spacing between it and K to become smaller which reduces the velocity loop damping associated with K Reducing Koj also causes the loop spacing between it and Kp to become smaller which reduces the position loop damping asso
9. 0 931 Load Obs Config With Vel Est Parameter List 1 0 932 Load Obs Bw 389 rd s rn Taba 1 0 933 Load Obs Int Bw 0 rd s 5 Enable the Low pass Output Filter and set the Low pass Output Filter Bandwidth equal to zero to properly disable it Sercos IDN P 065 has an impact on how the Low pass Output Filter functions See Table 5 on page 22 for more information 6 Execute a move profile and run a trend to observe the mechanical performance IMPORTANT Ifan audible noise exists at any time use a smart phone app to identify resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to tune out resonant frequencies EtherN et IP Drives The following subsections provide information for auto tuning of EtherNet IP drives Bump Test When autotune performs the bump test a momentary tuning torque is applied to the motor while the acceleration and deceleration times are measured This information is then used to calculate the load ratio R system inertia torque scalar and system acceleration The bottom parameters on the Tune tab of the Axis Properties dialog box are used to keep the motor and load within specified position velocity acceleration and direction limits during the bump test 50 Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 Figure 43 EtherNet IP Drive Autotune Bump Test Parameters Gereral Tune Control Loop by M
10. 9723668 Position Units s A Additional Tune Feedforward Compensation Filters Limits Planner System Inertia 0 3038342 e Rated Rev s 2 Backlash Compensation 0 0 Position Units Torque Offset 0 0 e Rated Load Observer Configuration Load Observer with Velocity Estimate Friction 0 0 Rated Load Observer Bandwidth 77 87874 Friction Compensation 0 0 Position Units Load Observer Integrator Bandwidth U U Hertz Is Further Tuning Required Here are some observations that indicate the servo drive can produce satisfactory performance without additional tuning e Visibly smooth motion from a smooth cycle profile e Little to no audible noise produced during and after a commanded motion e Position and or velocity errors are within what is required for the application e Position and or velocity errors are repeatable If the load does not respond as intended consider these factors before tuning e Investigate proper servo sizing The best way to do this is to model the axis in Motion Analyzer software to verify the proper sizing of the motor and drive for the specified load and move profile You can also compare various design options for gear ratio load size coupling configuration high resolution versus low resolution feedback device and so forth Rockwell Automation Publication MOTION AT005B EN P November 2015 59 Chapter3 Autotuning e Simulate the axis in Motion Analyzer sof
11. IP Drive Load Ratio and Torque Scalar Categories General haractenstics of Motor Load Motor Model Load Inertia Mass Motor Feedback Load Coupling Compliant v som 7 Use Load Ratio Hookup Tests Polarity Load Ratio 20 0 Load Inertia Motor Inertia Motor Inertia 0 000044 Kgm 2 0a Backlash i Comphance Friction Torque Scalar hte Inertia Mass Compensation Position Loop System Iriertta 0 3038342 Rated Rev s 2 Vetociy coop System Acceleration 323 12585 Rev s 100 Rated Acceleration Loop You can enter R manually or you can run an autotune to calculate it automatically Parameter values that are affected by the torque scalar are then updated Other considerations are given e WhenR is entered higher than the actual load ratio the velocity loop bandwidth that is shown in the Axis Properties dialog box is artificially lower than its actual bandwidth The opposite is also true e The actual value of K in the motor electrical decreases as the motor heats up Sercos drives use a hot K value in the torque scalar to compensate which results in a torque scalar value that is approximately 2096 higher than it is for similar EtherNet IP drives e Sinceautotune is typically executed with a cold motor EtherNet IP drives calculate the torque scalar using the cold motor K to compensate This calculation results in a more conservative torque scalar approximately 2096 lower than Sercos drives guarding the system from
12. Load Observer Internal Gains for Kinetix 5500 Kinetix 6000 and Kinetix 6500 Drives Acceleration Command Acceleration Reference Torque Estimate Kim Kou Acceleration Estimate Kor Feedback Feedback Velocity Position Velocity Estimate O s 0 O B A op Load Observer Plant Load observer gains that require user interaction are Load Observer Bandwidth Kop and Load Observer Integral Bandwidth K They are set by IDN P 432 and IDN P 433 respectively Guidelines for setting these gains are provided in the following sections In general Kop acts like a velocity integrator without windup and K acts like a position integrator without windup Typically K 0 Load observer gains that do not require user interaction are Load Observer Feedback Gain K and Load Observer Input Gain K They are automatically set internally based on the Load Observer Configuration Rockwell Automation Publication MOTION AT005B EN P November 2015 21 Chapter 1 22 Background However when in Acceleration Feedback mode K can also be set manually by using IDN P 434 with typical values between zero and one Table 3 Load Observer Gain Parameters 1 This value applies to drive firmware revision 1 124 and 1 125 2 This value applies to drive firmware revision later than 1 125 The Acceleration Estimate and Torque Estimate signals are read with IDN P 435 and P 436 respectively Definitions for these IDN parameters are gi
13. Test When autotune performs the bump test a momentary tuning torque is applied to the motor while the acceleration and deceleration times are measured This information is then used to calculate the load ratio R torque scalar and system inertia The top four parameters on the Tune tab of the Axis Properties dialog box are used to keep the motor and load within specified position velocity acceleration and direction limits during the bump test Rockwell Automation Publication MOTION AT005B EN P November 2015 43 Chapter3 Autotuning Figure 39 Sercos Drive Autotune Bump Test Parameters General Motion Planner Uris Dre Motor Motor Feedback Bux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset Fault Actions Tag Travel Limit 2 0 Position Units Speed 10 0 Position Units s DANGER Starting tuning procedure vath controller Torque Force 80 0 r Raad in Program or Run Mode causes ads mobon Forward LIni directional Dampang Factor 0 8 Tune C Postion Error Integrates C Velocity Error Integrator Friction Compensation Velocity Feediorward Acceleration Feedforward C Output Fiter Set the Direction of the autotune test based on the application requirements The default direction is Forward Uni directional Set the Travel Limit and Speed based on the physical limits dictated by the mechanics of the application Start with Torque Force 50 If the bump test fails chang
14. about the Pens tab e You can turn the pen on off by clicking Or in the visible tab which is useful when the trend window is too busy with several pens 4 Axisi PositionE nor Rockwell Automation Publication MOTION AT005B EN P November 2015 97 AppendixB Creating Trends for Tuning e Ifyou are trending a digital signal that is a start cycle stop e stop button and so forth you can remove the rise and fall slope due to the sampling of the trend and change the Type from Analog to Digital Pen nme o E iss Commando e Setting the Min and Max values can be very convenient if the Automatic Mode is not suiting the way the trend visually appears In this case you set the Min and Max value of the pen for example Position Error and Velocity Error where you want these to be relatively small Make sure to balance the value out across the X Axis by setting both Min and Max values the same Name General Display Pens XAxis Y Axis Template Sampling Start Trigger Stop Trigger Pen Attributes mu TagE spr LIme Sye a Me e SE ing fee DIGG IIBUBGI Eng U m o 4 Axisl PositionE mor Analog 050000 a Aui r itti soa amp Axisl CunentFeedback Analog None 2 200 000000 X Axis Tab In the X Axis tab the only pertinent information for tuning is the scale of time for the axis Change th
15. an audible noise exists at any time while tuning use a smart phone app to identify the resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to manually tune out resonant frequencies This may occur a few times as you increase K before instability occurs 10 Continue increasing Kp until a low pitch growling sound occurs or when oscillation occurs in the Velocity Error Torque Reference signal as shown in the following example This is the point where instability begins and Kyp cannot be successfully increased any further Tuning Friday October 09 2015 Axis1 Command velocity 11 999999 11 999993 f xis TorqueReterence 67 848640 64 788658 Axis1 VelocityError 0 097946 0 093529 11 999993 67 848640 11 999999 64 788658 0 097946 0 093529 2 05 02 305 PM 2 05 04 305 PM 11 Decrease Kvp by dividing it by two Rockwell Automation Publication MOTION AT005B EN P November 2015 65 Chapter4 Manual Tuning Axis1 Command Velocity 11 999999 Tuning Friday October 09 2015 11 999999 11 999993 y Axis1 TorqueReference 32 829651 29 381867 Axis1 YvelocityError 0 094786 0 084831 11 999993 12 13 14 15 16 r 18 32 829851 29 381867 0 094786 0 084831
16. applications speed increasing the speed to match your application requirements 6 Run the trend 7 Incrementally increase Kp while observing a reduction in the Velocity Error trend You may need to stop motion after each modification of Kp 64 Rockwell Automation Publication MOTION AT005B EN P November 2015 Manual Tuning Chapter 4 Tuning Friday October 09 2015 Axis1 Commandelocity 11 999999 11 999993 999999 20 48 571 PM Axis1 TorqueReference 20 789208 21 043554 Axis1 VelocityError 0 225193 0 227839 11 999993 20 799208 21 043554 0 225193 0 227839 1 49 42 407 PM 1 49 44 407 PM 8 Optionally you can enable Load Observer with Velocity Estimate in supported drives See Load Observer Feature on page 18 for more information a If the load ratio R 0 and Load Observer with Velocity Estimate is enabled set Kop 4 0 Kp b If the load ratio R gt 0 and Load Observer with Velocity Estimate is enabled set Kop 107 Kp Note that Kop s057 Kip works better in some applications c Every time you increase or decrease K in the following steps also increase or decrease K keeping the ratio between K and Kop op constant 9 Continue increasing K until ringing occurs in the Torque Reference or an audible high frequency noise is present IMPORTANT lfringing occurs in the Torque Reference signal or
17. as compliant As a result you often must de tune the control loop gains Defaults for other relevant parameters are given Velocity Feedforward Gain K g 0 100 Acceleration Feedforward Gain K g 0 100 Low pass Filter Bandwidth LP 4xK 2n Rockwell Automation Publication MOTION AT005B EN P November 2015 45 Chapter 3 46 Autotuning Start Tuning Follow these steps to execute an autotune It may be beneficial to run a trend in conjunction with executing an autotune See Appendix B on page 95 for more information 1 Click the Start Tuning button on the Tune tab in the Axis Properties dialog box For variable inertia loads perform an autotune at the point of lowest mechanical inertia If you manually calculate the Load Inertia Ratio enter the minimum load inertia on the Output tab General Motion Planner Units Dree Moto Motor Feedback Bux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions Tag Travel Limit 20 Position Units Speed 10 0 Position Units s DANGER Starting tuning procedure vath controller Torque Force 80 0 Rated ree oF ere Direction Forward Unidirectional v Damping Factor 0 8 Tune C Position Error Integrator C Velocity Error Integrator C Friction Compensation v Velocity Feedforward _ Acceleration Feedforward Output Filter After the autotune completes a bump test a Tune Results dialog box displ
18. break the sticktion in the presence of a non zero position error This is done by adding or subtracting a fixed torque level as determined by the Static Friction Compensation attribute to the torque reference signal value based on its current sign This form of friction compensation is applied only when the drive is static that is when there is no change in the position command The Static Friction Compensation value must be just under the value to overcome the sticktion A larger value results in dither a phenomenon describing a rapid back and forth motion of the load centered on the commanded position as it overcompensates for the sticktion Rockwell Automation Publication MOTION AT005B EN P November 2015 Filters and Compensation Chapter 5 To address the issue of dither when applying Static Friction Compensation a Friction Compensation Window is applied around the current command position when the load is at rest If the actual position error is within the Friction Compensation Window the Static Friction Compensation value is applied to the servo drive output but scaled by the ratio of the position error signal to the Friction Compensation Window Within the window the position loop and velocity loop integrators are also disabled to avoid the hunting effect that occurs when the integrators wind up Thus once the position error reaches or exceeds the value of the Friction Compensation Window attribute the full Static Friction Co
19. can be increased e Provides tighter control of moving parts reducing wear and saving material costs How It Works The load observer acts on the acceleration signal within the control loops and monitors the Acceleration Reference and the Actual Position feedback The Load observer models an ideal unloaded motor and generates a load Torque Estimate that represents any deviation in response of the actual motor and mechanics from the ideal model This deviation represents the reaction torque placed on the motor shaft by the load mechanics It is estimated in real time and compensated by closed loop operation Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Figure 15 Load Observer Block Diagram Position Command Control Loops Velocity Estimate Torque Estimate Servo Drive Power Conversion Unloaded Motor Acceleration Reference Torque Load Load Observer Position Feedback The load observer also generates a Velocity Estimate signal that you can apply to the velocity loop The Velocity Estimate has less delay than the Velocity Feedback signal derived from the actual feedback device It also helps to reduce high frequency output noise caused by the load observer s aggressive action on the acceleration reference Together the Load Observer with Velocity Estimate provides the best overall performance for positioning applications The following table desc
20. commanded to move Sercos Drives For a Sercos drive the friction related values are located in the Offset tab of the Axis Properties dialog box in the Logix Designer application Rockwell Automation Publication MOTION AT005B EN P November 2015 77 Chapter5 Filters and Compensation Backlash Compensation 78 Figure 58 Sercos Drive Friction Compensation Attributes General Motion Planner Units Drive Motor Motor Feedback AuxFeedb Homing Hookup Tune Dynamics Gans Output Limits Offset Fe Friction Compensation Friction Compensation 1 E l Manu Window 0 0 Pasition Units EtherNet IP Drives For an EtherNet IP drive the friction related values are located on the Load tab of the Axis Properties dialog box in the Logix Designer application Figure 59 EtherNet IP Drive Friction Compensation Attributes gt Axis Properties Axis1 Categories General Friction Compensation Motor Ar l Model Sliding Friction Compensation 0 0 Rated Motor Feedback Compensation Window 0 0 Position Units Scaling Hookup Tests Polarity Autotune Load Backlash Compliance Ma aiina l aan A number of important compensation features are included in the torque control diagram Backlash Compensation is used to stabilize the device control loop behavior in applications with high load inertia ratios and mechanical backlash The Backlash Compensation Window attribute is used to control the Backlas
21. every integer increase this value is negative doubles the system bandwidth Every integer decrease halves the system bandwidth e Enable Velocity Integrator in Position Mode checkbox this enables the K gain when checked Experience suggests not enabling this in a positioning type application However if tracking during an index is required then enabling K lets the servo drive track better during commanded motion Rockwell Automation Publication MOTION AT005B EN P November 2015 83 Chapter6 Kinetix 300 Drive Tuning Manual Tuning 84 Mscope 192 168 1 70 How It Works It is important to note that the autotune function is not the same as the bump test in the Logix Designer application The Kinetix 300 drive autotune sequence works as follows e Several bi polar steps are sent out and the response is measured Current steps are used in velocity mode Velocity steps are used in position mode e The PID gains are calculated based on the response e If you chose both velocity and position response the shape and number of steps are quite different as it is possible both loops are not tuned Figure 65 Scope Trace of Step Pulses During Autotune ici xg C t Velocity Command hd r We a Ae 0 0 1 i du PT 7 CUR b si User Units Div User Units oF T m User Units Div Time Base 50 ms Div Trigger Ch1 Rising Edge T Trigger Level 0 00 User Units Stop
22. not already suppressed by filters e MF resonances that are suppressed by filters but the filter bandwidths that are too close to the closed loop bandwidth e LF resonances that result when load observer is not applied with the recommended out of box settings e LF resonances that result from classical instability Figure 30 Identifying One LF Resonance Torque Loop Signal Frequency Responsa Magnitide Motor Ralbed Frequency Hz We do not recommend enabling Gain Stabilization on vertical loads as detuning may cause load drops Rockwell Automation Publication MOTION AT005B EN P November 2015 29 Chapter 1 30 Background Magnitude 6 Motor Rated Tracking Notch Filter and Gain Stabilization In this mode adaptive tuning applies the Tracking Notch Filter if required followed by Gain Stabilization if required Figure 31 Tracking Notch Filter and Gain Stabilization Mode Load Adaptive Tuning Backlash Adaptive Tuning Configuration Tracking Notch Filter and Gain Stabilization m Torque Notch Filter High Frequency Limit 2000 0 Hertz Observer Torque Notch Filter Low Frequency Limit 296 33984 Hertz Position Loop Torque Notch Filter Tuning Threshold B00 Motor Rated Velocity Loop In the following figure the parts of the control loop structure affected by adaptive tuning are highlighted in blue Figure 32 Tracking Notch Filter and Gain Stabilization Configuration Position Feed C
23. produces motion approaching but not beyond the dynamic travel limits of the machine Use Distance Scaling to increase or decrease the travel distance from 1 revolution Use Time Scaling to increase or decrease the period from 4 seconds Set Execution Mode to Once or Continuously depending on the number of times you want to safely execute the move An example CAM table is shown that produces a velocity step command for tuning the velocity loop This is the most aggressive motion profile you can create As a result we recommend that you use this one only if you are experienced in manual tuning and the machine mechanics are robust enough to handle the high jerk Y v oo QAR Um L2 ul um uad LI 0 J b 1 0 Linear J90 eer m Nlazter 315 Use Distance Scaling to change the velocity step magnitude Use Time Scaling to change the time period Rockwell Automation Publication MOTION AT005B EN P November 2015 Example 3 np otanpa hg Hastarterye hp Staniove inp RrverseDarecton Creating Move Profiles for Tuning Appendix A This is an example to perform a MAM instruction that rotates the motor shaft back and forth If your application cannot perform a bidirectional move then sequence a unidirectional move An example for a bidirectional move is shown below MA Moton axa Move Aon Am 1 Meher control umi Mowe Type 1 Wrk bbs 0 np Re
24. suppression This setting provides a Velocity Estimate in place of Velocity Feedback This produces a smooth feedback signal but can add steady state error generating a fictitiously lower velocity error As a result of the potential error it is not recommended to use in velocity mode Also position integrator or observer integrator should be used with setting in position mode This setting creates a filtered acceleration feedback signal It corrects errors but is fairly aggressive As a result the observer bandwidth must often be cut in half or significantly reduced for stable operation This setting is similar to Load Observer Only but doesn t use an Acceleration Reference input signal to mitigate additional phase lag delay created by necessary filtering It does not provide a Velocity Estimate in place of Velocity Feedback Rockwell Automation Publication MOTION AT005B EN P November 2015 19 Chapter1 Background The following figures depict the high level operation of each observer mode Figure 16 Load Observer Disabled Configuration Value 0 Servo Drive Position Command Control Loops Unloaded Motor B Torque Estimate Acceleration Reference S Velocity Estimate oad Observer Position Feedback Figure 17 Load Observer Only Configuration Value 1 Servo Drive Position Command Control Loops Unloaded Motor B Torque Estimate Acceleration Reference Velocity Estimate oad Observer Po
25. the Compliance tab in the Axis Properties dialog box EJ Load Adaptive Tuning Adaptive Tuning Configuration Tracking Notch Filter Friction i Torque Notch Filter High Frequency Limit 2000 0 Hertz bserver Torque Notch Filter Low Frequency Limit 296 33984 Hertz Position Loop Torque Notch Fiter Tuning Threshold B0 O 3 Motor Rated Velocity Loop b For Kinetix 6500 drives briefly enable the axis with an MSO motion direct command followed by an MSF instruction If an audible noise exists at any time use a smart phone app to identify resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to manually tune out resonant frequencies 5 IMPORTANT If required reduce the Maximum Acceleration and Deceleration to meet application requirements and to protect the drive and motor from overload With Load Inertia Ratio 0 acceleration limits are set to their maximum value providing the best performance for an unloaded motor However the motor is loaded and may not be able to accelerate as fast As a result you may have to reduce the Maximum Acceleration and Deceleration to meet application requirements Categories Is Further Tuning Required pae odel Acceleration Limit 4081 3 477 Position Units s 2 Motor Feedback Deceleration Limit 40819 477 Position Units s 2 Scaling Hookup Tests Polarity Autotune Load Backlash Compliance Friction
26. this setting e A damping factor of z 1 5 produces low responsiveness which is characterized by a slower response similar to decreasing the bandwidth The default setting in a Sercos drive is z 0 8 and the default setting in an EtherNet IP drive is z 1 0 A lower damping factor decreases the spacing between the position velocity and torque loop bandwidths generating under damped responses in actual position and actual velocity trends A higher damping factor generates over damped responses Rockwell Automation Publication MOTION AT005B EN P November 2015 Drive Model Time Constant Command Torque Scalar Background Chapter 1 Drive model time constant DMTC is the sum of all delays around the torque loop for a given drive and motor The following figure shows the delays that are associated with the DMTC Figure 10 Delays Associated with DMTC PI Regulator Computational Delay Actual Motor Electrical Time Constant Feedback Sample Delay DMTC values for different Kinetix drives are shown in Table 1 on page 14 It can be obtained in the Logix Designer application through a GSV instruction as shown in this example Current Loop Time Constant Feedback Filter Time Constant StartG sv GEM Get System Value Class Mame Axis Instance Mame Axis Attribute Mame DrivetModelTimeConstant Desi DriveTimecConst 1 00 3306256 003 The DMTC is used to calculate the torq
27. to suppress audible vibration noise and high frequency resonances For more information see Compensating for High Frequency Resonances on page 69 When enabled autotune calculates the Low pass Output Filter Frequency LP in Hz Low pass Filter Bandwidth LP 4 x Kp 2 m Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 e Integrator Hold When Integrator Hold is enabled the servo loop temporarily disables the position and velocity integrators while the velocity command is non zero This feature is used in point to point moves to minimize the integrator wind up and phase lag during motion When Integrator Hold is disabled all active position and velocity integrators are always enabled Using Load Observer with Autotune This procedure applies to Kinetix 6000 drives It involves configuring the load observer feature after executing an autotune This method also works for any existing set of gains where the Load Inertia Ratio is known or manually calculated that is when the Load Inertia Ratio gt 0 However we advise that you first try the Sercos drive recommended settings See Sercos Drive Recommended Settings on page 34 for more information 1 Click the Tune tab in the Axis Properties dialog box and perform an autotune Follow all of the steps in Start Tuning on page 46 2 Click the Output tab in the Axis Properties dialog box and verify that the Load Inertia Ratio gt 0 If
28. tuning a Kinetix drive system The information given here is intended for motion control users with skill levels ranging from novice to advanced Each component of the control structure is described in detail and out of box tuning auto tuning and manual tuning techniques are presented Integrated Motion on the EtherNet IP network uses CIP Motion and CIP Sync technology from ODVA all built on the Common Industrial Protocol CIP For convenience drives that use this technology are referred to as EtherNet IP drives These documents contain additional information concerning related products from Rockwell Automation Resource Description Logix5000 Controllers Quick Start publication 1756 QS001 Start programming Logix5000 controllers Logix5000 Controllers General Instructions Reference Get detailed information about Logix based Manual publication 1756 RM003 instructions Logix5000 Controllers Motion Instructions Reference Get detailed information about Logix based motion Manual publication MOTION RM002 instructions Integrated Motion on the EtherNet IP Network User Manual Configure and startup integrated motion applications publication MOTION UM003 Kinetix 6000 Multi axis Servo Drives User Manual Install configure and troubleshoot Kinetix 6000 publication 2094 UM001 applications Kinetix 6200 6500 Modular Multi axis Servo Drives User Install configure and troubleshoot Kinetix 6200 6500 Manual publication 2094 UM002 applic
29. value bar trend information for tuning 100 velocity loop block diagram EtherNet IP drives 111 controller 10 manual tuning 63 vertical axis with holding brake tuning CIP drives 108 considerations 106 Sercos drives 107 viscous friction compensation 77 X X Axis tab to create trends for tuning 98 Y Y Axis tab to create trends for tuning 99 Rockwell Automation Publication MOTION AT005B EN P November 2015 Index 115 Index Notes 116 Rockwell Automation Publication MOTION AT005B EN P November 2015 Rockwell Automation Support Rockwell Automation provides technical information on the Web to assist you in using its products At http www rockwellautomation com support you can find technical and application notes sample code and links to software service packs You can also visit our Support Center at https rockwellautomation custhelp com for software updates support chats and forums technical information FAQs and to sign up for product notification updates In addition we offer multiple support programs for installation configuration and troubleshooting For more information contact your local distributor or Rockwell Automation representative or visit http www rockwellautomation com services online phone Installation Assistance If you experience a problem within the first 24 hours of installation review the information that is contained in this manual You can contact Customer Support for ini
30. will have to incrementally increase Position Loop Bandwidth in successive autotunes to dial in the performance 3 Test the drive and observe mechanical performance and stability a Create a move profile in the Logix Designer application to observe the behavior of the mechanics while tuning See Appendix A for more information on Creating Move Profiles for Tuning An example CAM table for an MATC instruction is shown below Lure gris b Createa trend in the Logix Designer application to monitor Command Position Command Velocity Torque Reference Position Error and Velocity Error See Appendix B for more information on how to Create Trends for Tuning An example trend is shown below cet ae SSS CL Turan Fride October f aii GE ena 1 AA ETE PM E a ini Terai HMO n n L viet Terqueisierenes 20 7TECUOR EE LT isal Pbro Domi Adwa Damay 199998 E Arini VekedyEmm DIEM zem L 30 Tio y y F LH Ww Wve m WW ELLA Lis Pelt l4 T M E AMA i E Ent hr eM leer aa AJUS x TS ae own Sgn i z MW c I dm 1 m AA ao Rockwell Automation Publication MOTION AT005B EN P November 2015 47 Chapter 3 48 Autotuning c Goonline with the controller and have the drive in a Ready state d Enable the drive with an MSO instruction or motion direct command IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have s
31. x EET Model 1 Custom E Perform Tune Motor Feedback Sealing Rees Meshur v Hookup Tests Polarity rs Rid v Loop Parameters Tuned Load Customize Gains to Tune Backlash C Position Integrator Bandwidth sami 7 Velocity Integrator Bandwidth Observer v Velocity Feedionward Position Loop Acceleration Feedtonward Velocity Loop 2 Click the Load tab in the Axis Properties dialog box a Check Use Load Ratio b Set the Load Ratio 0 Categories General haracterstics of Motor Load S Moto Model Load Inertin see Motor Feedback Load Coupling Rigid Y Scaling i R Hookup Tes v Use zs atio Folanty Load Ratio 0 0 Load Inertia Motos Inertia Motor Inertia 0 000044 kgm 3 Click the Observer tab in the Axis Properties dialog box a From the Configuration pull down menu choose Load Observer with Velocity Estimate Configuration Load Observer with Velocity Estimate w Parameters Bandwidth 311 51495 Hertz Integrator Bandwidth 0 0 Hertz Posten m b Click Apply and then click Yes to update all dependent attributes The Load Observer Bandwidth and other gains are set automatically 1 1 OO O 0 0 0 Rockwell Automation Publication MOTION AT005B EN P November 2015 39 Chapter2 Out of Box Tuning 4 IMPORTANT Suppress resonances a For Kinetix 5500 and Kinetix 5700 drives choose Tracking Notch Filter from the Adaptive Tuning Configuration pull down menu on
32. 1 6646 Rev s 2 Acceleration Loop Torque Current Loop Planner Homing Active Load Compensation Achons Torque Offset 0 0 Rated Dive Parameters 2 Verify the autotune direction is bidirectional 3 Perform an autotune 4 Perform a bump test that is check Measure Inertia using Tune Profile L ouphng Customize Gains to Tune Backlash Position Integrator Bandwadth Compliance Friction Observer Velocity Feedionward Position Loop Acceleration Feedforward Velocity Loop Acceleration Loop Torque Current Loop Planner Measure Inertia using T une Profile Homing Actions 5 Use the trend to monitor the performance of the axis See Creating Trends for Tuning on page 95 for details IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have safeguards in place to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion 6 Enable the drive with an MSO instruction 7 Introduce a 196 Torque Offset while monitoring the position error 8 Increase the Torque Offset until the position error is zero and the drive is performing well 9 Disable the drive with an MSF instruction See Manual Tuning on page 61 for details 108 Rockwell Automation Publication MOTION AT005B EN P November 2015 Appendix E iagrams uonisog peqpae4 peqpaa4 xny 40je nuun y uonisog
33. 1 s Kvp Velocity 0 0 x Integral 0 0 l ms s Kvi Acceleration 0 0 In an EtherNet IP drive the position and velocity loop controllers are configured with a proportional term top in series with an integral term bottom as shown in the following figure A factor of 2 7 is also applied to each gain This configuration places all control loop gains in units of Hz As a result all gains are proportional to each other and represent bandwidths that relate directly to physically measurable signals that are easy to understand More importantly removing any squared relationships simplifies the math when tuning an axis because all gains are related to each other by simple ratios Figure 4 EtherNet IP PI Controllers Series Form Position Loop PI Controller Velocity Loop PI Controller The following definitions are given for control loop gains of an EtherNet IP drive e Kj Position Loop Bandwidth Hz e K i Position Integral Bandwidth Hz e Kye Velocity Feedforward e Kp Velocity Loop Bandwidth e K Velocity Integral Bandwidth e K g Acceleration Feedforward ex b r1 F r3 r3 m r3 N a ex L These gains can be accessed on the Position Loop and Velocity Loop tabs of the Axis Properties dialog box in the Logix Designer application Rockwell Automation Publication MOTION AT005B EN P November 2015 11 Chapter1 Background Figure 5 EtherNet IP Position Loop Gains in the Logix Designer Application Ge
34. 100 X Axis tab 98 Y Axis tab 99 value bar information 100 D damping factor 14 display tab to create trends for tuning 96 drive model time constant DMTC 15 Index EtherNet IP drives autotuning bump test 50 gain calculation 52 backlash compensation 80 block diagram position loop 110 torque current loop 112 velocity loop 111 lead lag filter 75 low pass filter 75 notch filter 73 out of box tuning gain calculation 37 Kinetix 5500 and 6500 drive recommended settings 38 F feedback filter only Kinetix 300 drives 88 feedback for acceleration 22 feedback gain Kof 21 feedforward commands 9 filter Kinetix 300 drives feedback 88 low pass 88 notch 88 resonator 88 lead lag only EtherNet IP drives 75 low pass EtherNet IP drives 75 Sercos drives 74 notch 71 EtherNet IP drives 73 Sercos drives 72 filters and compensation 69 friction compensation 76 Sliding 77 Static 76 viscous 77 G general tab to create trends for tuning 95 high frequency resonance compensation 69 IDN messages to set load observer configuration attribute 103 gains 104 initialize the axis optional manual tuning 61 input gain Kou 21 integral bandwidth Koi 21 23 Rockwell Automation Publication MOTION AT005B EN P November 2015 113 Index 114 K Kinetix 300 drives autotuning 81 feedback filter 88 low pass filter 88 manual tuning 84 notch filter 88 resonator filter 88 tuning 81 Kinetix 5500 and 6500 drives autotuni
35. 2015 13 Chapter1 Background Damping Factor 14 Table 1 Bandwidth Comparison for Various Drive and Motor Combinations Drive or Loop Update Rate i Sarvo Control Motor Drive Model Torque Loop Module Bulletin No Time Constant Bandwidth Kinetix6000 125 us 125 us 125 ys 510 9 us 311 5 Hz m OD mm aue n 1531 us 103 95 Hz Kinetix 350 500 us 500 us 125 us 1003 9 us 158 53 Hz 1031 25 us 154 33 Hz MPL H 2 2024 ys 78 65 Hz 1062 5 us 149 8 Hz Y Kinetix5500 125 ys 125 us 125 us 537 Us 296 34 Hz 1756 M02AE 500 us 250 us 1502 us 106 Hz Servo Module 1 This motor has a high resolution encoder 2 This motor has an incremental low resolution encoder Damping factor is commonly referred to as zeta z It affects the rise time for a given bandwidth The following figure shows how the damping factor affects actual response with feed forwards disabled solid compared to its command motion profile dashed Figure 9 How Damping Affects Transient Response Over damped A M DP i HiT Critically damped 1 H Low z 1 5 SEM sees RM i Medium 7 1 0 High z 0 8 e A damping factor of z 0 8 produces high responsiveness which is characterized by a faster rise time but with overshoot e A damping factor of z 1 0 produces medium responsiveness which is characterized by the fastest possible rise time without overshoot We recommend
36. Application Techniques Allen Bradley Motion System Tuning a E T i T at T r id k Lg Allen Bradley Rockwell Software Automation Important User Information Read this document and the documents listed in the additional resources section about installation configuration and operation of this equipment before you install configure operate or maintain this product Users are required to familiarize themselves with installation and wiring instructions in addition to requirements of all applicable codes laws and standards Activities including installation adjustments putting into service use assembly disassembly and maintenance are required to be carried out by suitably trained personnel in accordance with applicable code of practice If this equipment is used in a manner not specified by the manufacturer the protection provided by the equipment may be impaired In no event will Rockwell Automation Inc be responsible or liable for indirect or consequential damages resulting from the use or application of this equipment The examples and diagrams in this manual are included solely for illustrative purposes Because of the many variables and requirements associated with any particular installation Rockwell Automation Inc cannot assume responsibility or liability for actual use based on the examples and diagrams No patent liability is assumed by Rockwell Automation In
37. MOTION AT005B EN P November 2015 Out of BoxTuning Chapter 2 2 56 e e e e D 66 5 Configure these settings and values on the Gains tab a Position Proportional Gain K b Velocity Proportional Gain K c Velocity Feedforward Gain 100 d Integrator Hold Disabled General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions Tag Position Gains Proportional 223 17s Integral 0 0 1 ms s Velocity Gains Feedforward Gains Proportional 489 3265 l s Velocity 100 0 x Integral 00 Vmsss Acceleration 9 0 x Integrator Hold Disabled bi 6 Configure these IDN parameter values Note that there is an offset of 500 in IDN values in DriveExplorer compared to MSG instructions a IDN P 431 2 Load Observer with Velocity Estimate b IDN P 432 Kop c IDN P 433 0 d IDN P 065 1 File Edit Explore Actions Help suiruees uoss ue H Node 1 2094D SERVO 2 0930 Reserved 5 0 2094D SERVO Config 0000 1 0 931 Load Obs Config ai Vel Est ca TARA 1 0 933 Load Obs Int Bw 0 rd s 7 Click the Output tab in the Axis Properties dialog box and verify these settings a Load Inertia Ratio 0 b Enable Low pass Output Filter Unchecked Rockwell Automation Publication MOTION AT005B EN P November 2015 35 Chapter2 Out of Box Tuning General Motion Planner Units Drive
38. Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset Fault Actions Tag Motor Inertia 0 000044 Kg m 2 Manual Adjust Load Inertia Ratio 0 0 Load Inertia Motor Inertia Torque Force Scaling 0 01749257 Rated Position Units s 2 System Acceleration 5716 713 Position Units s 2 at 100 Rated Enable Notch Filter Frequency Enable Low pass Output Filter 8 IMPORTANT Suppress resonances a Briefly enable the axis with an MSO motion direct command followed by an MSF instruction b If an audible noise exists at any time use a smart phone app to identify resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to manually tune out resonant frequencies 9 IMPORTANT If required reduce the Maximum Acceleration and Deceleration to meet application requirements and to protect the drive and motor from overload With Load Inertia Ratio 0 acceleration limits are set to their maximum value providing the best performance for an unloaded motor However the motor is loaded and may not be able to accelerate as fast As a result you may have to reduce the Maximum Acceleration and Deceleration to meet application requirements General Motion Planner Units Drive Motor Motor Feedback i Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions
39. N P November 2015 Appendix D Vertical Axis Tuning Vertical axes present a constant force of gravity on the load This typically presents problems with the load dropping while enabling or disabling the axis Special consideration is required when tuning an axis to overcome these run time problems Regardless of whether a load observer is enabled we recommend applying one of the following methods 1 Torque offset method e Apply a constant torque offset to overcome the effect of gravity on a fixed inertia This is the most common method e Create application code that calculates and applies a changing torque offset to overcome the effect of gravity on changing inertia e The proper amount of torque offset will act as an electronic counterbalance allowing the control loops to solely focus on positioning 2 Integrator gain method e Apply a small amount of position integral gain e Applyasmall amount of load observer integral gain if the load observer is enabled e This method can be less effective than the torque offset method because the integrator takes a small period of time to accumulate from initial conditions until it can overcome the effect of gravity on the load In this time the load can drop e This method may be more effective than the torque offset method regarding ease of use in overcoming the effect of gravity on changing inertia The torque proving feature in some Kinetix drives may minimize the effe
40. NINE ERR aa TET 95 General dT abescceotiid sdb uoi totu cde LET E ER eA ex d 95 Dipl ADs sssnsseene ue ED UR n RERUM 96 Pons Api es riesen UO SSQR adis idit bas Eid Das 96 POCO ERNST ISIN 98 LANS AD esate Spats ag terete d pem eee ee 99 Sam Pline T ADs tesa snd ette eee Leia leaded aloes eis 100 Value Bar Information ccc ette EE RR obe Arp taies 100 Rockwell Automation Publication MOTION ATO05B EN P November 2015 Setting Sercos Gains with IDN Write Messages Vertical Axis Tuning Block Diagrams Table of Contents Appendix C Setting Load Observer Configuration Attribute Lue 103 Setane Load Observer Galfisoedeiseas tres dieque acd a nds 104 Appendix D CCOnisideratiODlS seco do tat oe bib oA o ott e eo to s 106 Tunne Net DD oda adde i e od bee beata Du A CR dede 107 Seros DEIVESS cari eoe tutte tire otl e ote e ae dac um Lesen iments oh 107 EtherNet IP Drives 0 cc cece cc IRR RR 108 Appendix E SECOS TIVE NN TREE ECC TRUE TT 109 EtherNet IP Drives 0 cece ccc RI RIRs 110 Position OOP sscduteme bebat Reti E AR ue aiu 110 pireisdboo MR EET 111 Torque G rrent Eo00p sou odios tr tERDLP teen die Ea 112 Rockwell Automation Publication MOTION AT005B EN P November 2015 5 Table of Contents Notes 6 Rockwell Automation Publication MOTION ATO05B EN P November 2015 About This Publication Additional Resources Preface The purpose of this publication is to assist you in
41. Observer Position Loop Velocity Loop Acceleration Loop General Acceleration Loop Here are some observations that indicate the servo drive can produce satisfactory performance without additional tuning e Visibly smooth motion from a smooth cycle profile e Little to no audible noise produced during and after a commanded motion e Position and or velocity errors are within the application requirements e Position and or velocity errors are repeatable e The cycle profile is within the thermal limits of the drive and motor If the load does not respond as intended consider these factors before tuning 40 Rockwell Automation Publication MOTION AT005B EN P November 2015 Out of BoxTuning Chapter 2 e Investigate proper servo sizing The best way to do this is to model the axis in Motion Analyzer software to verify the proper sizing of the motor and drive for the specified load and move profile You can also compare various design options for gear ratio load size coupling configuration high resolution versus low resolution feedback device move profile types and so forth e Simulate the axis in Motion Analyzer software testing various control loop gain settings to conclude the desired motion can be achieved Compliance and machine vibration can often be minimized by creating a more direct and stiff coupling between the motor and load Helping to achieve this are quality couplings gearboxes actuators and guides If the lo
42. P November 2015 63 Chapter4 Manual Tuning E xis CommandPosition 4 000018 TMOG CEAT Senet Ui 20 TS 0 000840 1 20 48 571 PM L Axis1 Command velocity 11 999999 11 999993 Axis1 TorqueReference 20 799208 21 043554 Axis1 PositionError 0 001424 0 000840 0 001410 11 939338 Axis1 VvelocityError 0 225193 0 227839 4 000018 11 999993 20 799208 21 043554 D 001424 0 001410 0 225193 0 227839 1 49 42 407 PM 1 49 44 407 PM 3 Isolate the velocity loop a Note the position and feed forward gain values Kp Kpi Ki and K g in the Axis Properties dialog box You must change them temporarily to isolate the velocity loop and later restore them to the original values b Temporarily configure these settings in the Axis Properties dialog box Kop 0 Ki 0 e K O K7100 e Low Pass Bandwidth 0 e Notch Filter Frequency 0 4 Go online with the controller and have the drive in a Ready state 5 Execute motion a Enable the drive with an MSO instruction or motion direct command IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have safeguards in place to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion b Execute the move profile Start the move cycles slowly at approximately 2 3 of the
43. Power Control and Information Solutions Headquarters Americas Rockwell Automation 1201 South Second Street Milwaukee WI 53204 2496 USA Tel 1 414 382 2000 Fax 1 414 382 4444 Europe Middle East Africa Rockwell Automation NV Pegasus Park De Kleetlaan 12a 1831 Diegem Belgium Tel 32 2 663 0600 Fax 32 2 663 0640 Asia Pacific Rockwell Automation Level 14 Core F Cyberport 3 100 Cyberport Road Hong Kong Tel 852 2887 4788 Fax 852 2508 1846 Publication MOTION ATOO5B EN P November 2015 Supersedes Publication MOTION AT005A EN P March 2014 Copyright 2015 Rockwell Automation Inc All rights reserved Printed in the U S A
44. Publication MOTION AT005B EN P November 2015 Trend Properties Dialog Box Appendix B Creating Trends for Tuning This appendix shows how to configure different trends in the Logix Designer application to observe the behavior of an axis while tuning Name Tab The Name tab is where you can change the name of the trend itself which is useful when you copy and paste a trend RSTrendX Properties Name General Display Pens X Axis Y Axis Template Sampling Start Trigger Stop Trigger Nowe Tuning_Trend Description General Tab An important part of the General tab is that the trend is typically set against time like an oscilloscope You can have an X Y plot which is useful when dealing with coordinated systems like robots RSTrendX Properties Name General Display Pens X Axis Y Axis Template S ampling St vV Display chart title Tuning Trend V Display progress bar while loading historical data Chart style 9 Standard XY Plot Rockwell Automation Publication MOTION AT005B EN P November 2015 95 Appendix B 96 Creating Trends for Tuning Display Tab Displaying milliseconds is useful when using the value bar of the trend The other settings are defaults Name General Display Pens Maxis Y Axis Template Samp Chart display options Time format Use system time setting _ Display milliseconds Chart radix V Display value bar Decimal
45. ack Aux Feedback Conversion Homing Hookup Tune Dynamics Gans Output Limits Offset FaulkActons Tag Motor Inertia 0 000044 Kg m 2 Load Inertia Ratio 15 155865 Load Inertia Motor Inertia Torque Force Scaling 0 2826076 Rated Position Units s 2 System Acceleration 353 84753 Position Units s 2 at 100 Rated Enable Notch Filter Frequency Enable Low pass Output Filter Low pass Output Filter Bandwidth Hertz If the Low pass Output Filter is enabled and load observer is not enabled verify that the Low pass Output Filter Bandwidth K 27 x 5 Rockwell Automation Publication MOTION AT005B EN P November 2015 Filters and Compensation Chapter 5 If the Low pass Output Filter and load observer are enabled verify that the Low pass Output Filter Bandwidth 2 max K Kop 27 x 5 Sercos IDN P 065 has an impact on how the Low pass Output Filter functions See Table 5 on page 22 for more information EtherNet IP Drives For an EtherNet IP drive click the Compliance tab in the Axis Properties dialog box Set the Torque Low Pass Filter Bandwidth to the desired frequency in Hz Figure 56 EtherNet IP Low Pass Filter Bandwidth Ganetal Compliance Compensation Motor Model Torque Low Pase Filter Bandwidth io Hertz Motor Feedback Torque Notch Filter Frequency D Hertz Nock Teste Torque Lag Fiter Gain 10 Polarity Torque Lag Filter Bandwidth 0 0 Hertz Autotune Load Backlash Compliance If the To
46. ad requires additional tuning to further optimize motion performance see Autotuning on page 43 and Manual Tuning on page 61 Rockwell Automation Publication MOTION AT005B EN P November 2015 41 Chapter2 Out of Box Tuning Notes 42 Rockwell Automation Publication MOTION AT005B EN P November 2015 Sercos Drives Chapter 3 Autotuning Out of box refers to default control loop gain settings that are pre configured for a new axis when it is created Because the load is unknown at this point the motor is assumed to be unloaded and the load ratio R 0 However when the load is known or an autotune has been performed the control loop gains are configured for a load ratio R gt 0 This is the primary difference affecting out of box and autotuning rules Thus the term out of box implies R 0 and the term autotune implies R gt 0 Autotune automatically performs two basic functions with minimal user intervention e Autotune momentarily initiates motion in a bump test to measure the load ratio R The torque scalar and system acceleration are then calculated from R Axis dynamics and limits are then calculated from these parameters e Control loop gains are calculated based on the torque loop bandwidth Tg which is determined from the drive model time constant DMTC which is based on the drive and motor selected The following subsections provide information for autotuning of Sercos drives Bump
47. adjust torque loop notch and low pass filter parameters to suppress resonances e Automatically de tune control loop gains to avoid instability when it is detected Benefits When adaptive tuning is enabled with recommended out of box control loop settings adaptive tuning does the following e Automatically suppresses changing resonances e Eliminates periodic identification of resonances and retuning e Eliminates the need for a tuning expert e Reduces commissioning time especially for high axis count e Minimizes the power consumption machine vibration and errors Mechanical Resonances Mechanical loads exhibit resonances that limit performance damage hardware consume energy and are noisy It is often left to the user to suppress these resonances through manual tuning a challenging and time consuming task Resonances result from various levels of compliance backlash and misalignment and can range in frequency from a few Hz to a few thousand Hz They typically increase in number and severity as controller gains are increased Resonances are classified in the following way 1 Motor Side Resonances Most mechanical resonances are reflected back to the motor and seen by the encoder As a result they are suppressed by tuning control loop gains the load observer and torque loop filter parameters a Low Frequency LF Resonances LF resonances are below the Torque Loop Bandwidth Since they are within the closed loop ban
48. afeguards in place to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion e Execute the move profile Start the move cycles slowly at approximately 2 396 of the applications speed with a period of 4 seconds increasing the speed to match your application requirements f Run the trend and observe the mechanical performance IMPORTANT Ifan audible noise exists at any time while tuning use a smart phone app to identify the resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to tune out resonant frequencies g Stop the trend h Stop the drive with an MAS instruction or motion direct command i Disable the drive with an MSF instruction or motion direct command Repeat the previous steps executing an autotune to incrementally increase the Position Loop Bandwidth until you achieve the highest performance within application requirements where the Torque Reference signal is not too oscillatory or noisy Other Parameters Other selection parameters on the Tune tab of the Axis Properties dialog box are listed below e Friction Compensation For more information see Friction Compensation on page 76 Torque Offset For more information see Appendix D on Vertical Axis Tuning Output Filter This check box enables the Low pass Output Filter It is used in conjunction with the Notch Filter
49. apture Samples 120000 Time Period The value bar is important because it shows instant values of each pen at the same point in time It also provides a time stamp which can be correlated to other trends if they are running simultaneously BEI Actuaivelocty 157766 INE 339782 12 03 070 AM S CommandVelocty 15 7766 13 9782 agieren 0 0526 0000 0 0466 EN VelocityError 262943 23 2970 E Current eedback 52 5886 46 5940 Another useful way to use the value bar is in delta mode where you can measure the width and magnitude differences of values in terms of time To do this right click inside the trend window and choose Delta from the Active Value Bar ee Axis ActualVelocty 15 7766 Tuning Trend Saturday April 20 2013 43 9782 ahaa 5 12 03 003 AM B o commanavelocty 15 7766 I 13 9782 BE 1 PostionError 00526 0 0000 oa 0 0466 9 925 IL mm Axis MelocityError 26 2943 A 28710 ERE xis CurentFeedback 52 5886 O F485940 2747 Scroll Active Value Bar L vw Show Value Bar Unda Zaamj Pan Print Trend Rockwell Automation Publication MOTION AT005B EN P November 2015 Creating Trends for Tuning Appendix B After choosing Delta the value bar locks on the starting point and when you click on the second location the delta value appears as time and the pen values are displayed 143 ms as shown in the example below
50. ations Kinetix 6000 and Kinetix 6200 6500 Drive Systems Design Determine what you need for Kinetix 6000 6200 6500 Guide publication GMC RM003 applications Kinetix 5500 Servo Drives User Manual Install configure and troubleshoot Kinetix 5500 publication 2198 UM001 applications Kinetix 5500 Drive Systems Design Guide Determine what you need for Kinetix 5500 applications publication GMC RM009 Kinetix 5700 Servo Drives User Manual Install configure and troubleshoot Kinetix 5700 publication 2198 UM002 applications Kinetix 5700 Drive Systems Design Guide Determine what you need for Kinetix 5700 applications publication GMC RM010 PowerFlex 700S and PowerFlex 755 Drives Tuning Manual Tune PowerFlex 700S 755 drives publication DRIVES AT004 Kinetix Tuningless Quick Start Guide publication Quickly tune Kinetix drives MOTION QS001A You can view or download publications at http www rockwellautomation com literature To order paper copies of technical documentation contact your local Allen Bradley distributor or Rockwell Automation sales representative Rockwell Automation Publication MOTION AT005B EN P November 2015 7 Preface Notes 8 Rockwell Automation Publication MOTION AT005B EN P November 2015 Chapter 1 Background This document is intended for motion control users that are familiar with the following e Kinetix servo drives e Sercos or EtherNet IP communication e Use of the Studio 5000 Logix Design
51. ays the Load Inertia Ratio resulting from the bump test The Position Loop Bandwidth K 2 x in units of Hz resulting from the gain calculation Tune Results 2 une Results E xj Postion Loop Bandwidth 155703 Henz Load Inertia FLatio EXE Load Inertia Motor Inatia DANGER The Bandvadth determined by the tune process E the maanum bandvadth Increasing Ihe bandvedth may ca Heo 2 At this point you can increase or decrease the calculated Position Loop Bandwidth to recalculate the gains with higher or lower values Ku 4000 4000 Determine if the mechanical system attached to the motor is rigid or compliant and adjust the Position Loop Bandwidth accordingly Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 e Rigid systems typically involve high performance load mechanics that are tightly coupled directly to the motor shaft and there is no lost motion Because the gains are auto calculated for rigid loads this type of load typically requires little to no adjustment of Position Loop Bandwidth to dial in the performance e Everything else is compliant including systems with belts and pulleys long shafts heavy loads and couplings and gearboxes with backlash and or lost motion For this type of load a good starting point is to reduce the Position Loop Bandwidth by a factor of the Load Inertia Ratio 1 to assure stability However performance is typically too low and you
52. c with respect to use of information circuits equipment or software described in this manual Reproduction of the contents of this manual in whole or in part without written permission of Rockwell Automation Inc is prohibited Throughout this manual when necessary we use notes to make you aware of safety considerations WARNING Identifies information about practices or circumstances that can cause an explosion in a hazardous environment which may lead to personal injury or death property damage or economic loss ATTENTION Identifies information about practices or circumstances that can lead to personal injury or death property damage or economic loss Attentions help you identify a hazard avoid a hazard and recognize the consequence gt gt IMPORTANT Identifies information that is critical for successful application and understanding of the product Labels may also be on or inside the equipment to provide specific precautions SHOCK HAZARD Labels may be on or inside the equipment for example a drive or motor to alert people that dangerous voltage may be present BURN HAZARD Labels may be on or inside the equipment for example a drive or motor to alert people that surfaces may reach dangerous temperatures ARC FLASH HAZARD Labels may be on or inside the equipment for example a motor control center to alert people to potential Arc Flash Arc Flash will cause severe injury or death Wear proper Personal Pr
53. catalog number e Delete the axis and drive and then re create them Configure these applicable axis parameters a Set the Loop Type Position Servo b Set the damping factor z 1 0 Loop Response Medium in an EtherNet IP drives Set K and K 0 Set K and Ky 0 Set Position and Velocity Integrator Hold Disabled cen Set Load Observer Configuration Disabled Set Kop and K 0 Set K gand K g 0 Set the Low Pass Filter Bandwidth 0 j Set the Notch Filter Frequency 0 k Set the Lead Lag Filter Gain 1 l Set the Lead Lag Filter Bandwidth 0 2 Q9 0 0 m Configure the axis dynamic limits a Set the Torque limits to what is required for the application b Change the Position Error Tolerance to a large value to avoid a fault c For an EtherNet IP drive change the Velocity Error Tolerance to a large value to avoid a fault Configure the Load Inertia Ratio a If you know R gt 0 from a previous autotune enter it into the Logix Designer application b If you calculated R at the point of lowest mechanical inertia enter it into the Logix Designer application c Otherwise set R 0 in the Logix Designer application Set an initial value for K Use a small value because the error tolerance has been changed For an EtherNet IP drive a value of Kp 3 Hz isa good starting point elocity Loop Gains 7 Parameters Bandvadth 3 0 Hertz Integrator Bandendth 0 0 Hert
54. ces Chapter 5 Filters and Compensation Approximately half of all motion applications exhibit high frequency resonances that are apparent by an audible high frequency squealing of the load mechanics Furthermore all applications will ultimately exhibit resonance when pushing gains to their limit while optimizing performance See Mechanical Resonances on page 24 for more information on the various type of resonances and how to suppress them For Kinetix 5500 and Kinetix 5700 drives see Adaptive Tuning Feature on page 24 to automatically compensate for high frequency resonances Otherwise follow these steps to manually identity and reduce the presence of high frequency resonances Follow these steps to identify and reduce the presence of high frequency resonances 1 Perform the following move sequence by using Motion Direct Commands a Enable the drive with an MSO instruction b Slowly jog the axis with a MAJ or MAM instruction C Stop the axis with a MAS instruction d Disable the drive with an MSF instruction IMPORTANT Sometimes an audible resonance is heard before the axis is jogged making the MAJ and MAS instructions unnecessary 2 Determine if an audible high frequency resonance exists in your motion application e Ifan audible high frequency resonance is not present during the move sequence skip the remaining steps and tuning is complete Rockwell Automation Publication MOTION AT005B EN P November 2015 69 C
55. ciated with loop spacing Figure 36 Effects of Unknown Load R 0 Loop Spacing Damping Velocity Loop Actual Velocity Loop Bandwidth Torque Scalar Integrator Damping To increase damping when Kp is artificially lowered all the other gains are decreased by an extra factor of 10 This provides satisfactory motion performance over a large class of unknown loads In an EtherNet IP drive the default damping factor is z 1 0 This produces a loop spacing of 47 4 The gains are calculated from the torque loop bandwidth T in units of Hz Velocity Loop Bandwidth K Ty 4z Position Loop Bandwidth K K 40z Velocity Integral Bandwidth K 0 or K 40z Position Integral Bandwidth K 0 or K 40z Rockwell Automation Publication MOTION AT005B EN P November 2015 37 Chapter 2 38 Out of Box Tuning Figure 37 EtherNet IP Drive Out of Box Gain Relationships without Load Observer z 1 0 Defaults for other relevant parameters are given Velocity Feedforward Gain K g 0 100 Acceleration Feedforward Gain K g 0 100 Low pass Filter Bandwidth LP 5xK When Load Observer with Velocity Estimate is applied it automatically accounts for the arbitrary load disconnect created by the load forcing it to function like an unloaded motor As a result standard 4 spacing sufficient for controlling an unloaded motor is applied when the load observer is enabled F
56. cos drives Rockwell Automation Publication MOTION AT005B EN P November 2015 9 Chapter1 Background the fine interpolators generate a second order position command a first order velocity feed forward and a zero order acceleration feed forward A zero order acceleration feed forward signal means that it is actually updated at the coarse update rate CUR This fact is one reason why many Sercos applications do not benefit from the use of acceleration feed forward Unlike Sercos drives the EtherNet IP drive fine interpolators also handle variable update times to compensate for non deterministic networks Torque Scalar and Motor Torque Constant Kt The torque scalar affects tuning and overall motion performance The motor torque constant affects the torque scalar See Torque Scalar on page 15 for more information on the torque scalar motor torque constant and the differences between EtherNet IP drives and Sercos drives Load Observer with Velocity Estimate See Load Observer Feature on page 18 for more information on the load observer and velocity estimate Adaptive Tuning See Adaptive Tuning Feature on page 24 for more information on adaptive tuning and tracking notch filtering Position and Velocity Loop Controllers In a Sercos drive the position and velocity loop controllers are configured with a proportional term top in parallel with an integral term bottom as shown in Figure 2 The proportional term equals the co
57. ct of load drops and consequently reduce the need for one of these methods Kinetix drives can use the autotune function to tune a vertical axis with a holding brake Rockwell Automation Publication MOTION AT005B EN P November 2015 105 AppendixD Vertical Axis Tuning Considerations Controlling a brake is not difficult if you use the tools provided Here are some factors to consider e The holding brake is not a stopping brake If the application attempts to stop the load with the brake the brake will not engage However if the zero speed detection occurs with significant torque at the brake the brake can be damaged over time You can use a mechanical stopping and or regenerative means on your axis outside of the holding brake if you need stopping power This can be modeled by using Motion Analyzer software e Brake drops on an E Stop This is not necessarily tuning related The brake uses a spline mechanism to engage and disengage Use of the physical holding brake requires time to engage this spline In the Logix Designer application it can mean that brake engage and brake release times are required or at least need to be investigated Below is an example of a few motor brake engage times and where these are located in the Logix Designer application for an EtherNet IP drive MP Serles Low Inertia Motor Brake Specifications ofi ERR Brake Response Time Coil Current Brake Motor Engage using external a
58. diagram UW ajey anbJo puewwo E J23lH J93 H Ed 39U31434 Y b Iul ia ul 2ual3Jay axuajgjoy LON EUN be pea P anualajay y anbio anbio anbioy pour p21J23 H MoputAM duo oney 41u f yeqpse4 anbio buiddoys Upiwpueg uie5Jayij T Mopurm duio uou EPP Ed pow Peqpee4 Bay Ww anbio ssed MO MgJeN T Duipijs duio uou 101621 feng Sog WWI enbao anbJo anbJo jnejs duio uomu Sn05A duio uon L PEIRA eng oneiyunjqp peqpaej peo peqpaa4 10704 onegiuQ epowpeqpaaj puewwo anbJo wj anbJo Rockwell Automation Publication MOTION AT005B EN P November 2015 112 A acceleration feedback 22 autotuning EtherNet IP drives bump test 50 gain calculation 52 gains load coupling 53 loop response 53 Kinetix 300 drives 81 Kinetix 5500 and 6500 drives 57 Kinetix 6000 drives 49 Sercos drives bump test 43 gain calculation 44 background on motion system tuning 9 backlash compensation 78 EtherNet IP drives 80 Sercos drives 79 bandwidth Kop 21 23 block diagram EtherNet IP drives position loop 110 torque current loop 112 velocity loop 111 Sercos drives 109 C compensation for backlash 78 friction sliding 77 static 76 viscous 77 high frequency resonances 69 create move profiles for tuning example 1 91 example 2 92 example 3 93 create trends for tuning Trend Properties dialog box display tab 96 general tab 95 name tab 95 pens tab 96 sampling tab
59. ds amp Tuning Trend E VO Configuration 1756 Backplane 1756 A10 ff 0 1756 L73 CIP_Motion S E 6 1756 EN2T ETH2T Module S a Ethernet f 1756 EN2T ETH2T Mod m j 2094 EN02D M01 51 Kinetix_6500_Drive_ Axis 1 192 168 1 121 Ad mt Mial AXIS CIP DRIVE Creating Trends for Tuning Appendix B Notice that you can use only two real time attributes at one time with a Sercos drive This means that if you want to monitor Velocity Error at the same time as Position Error and Torque Feedback you need to run two trends simultaneously and modify the real time values on the fly as you require them EtherNet IP Drives Typical pens used in tuning an EtherNet IP drive are shown below Some of these values show zero if they are not set to be read each cycle Select the Drive Parameters tab in the Axis Properties dialog box and check the parameters that you created pens for You may need to scroll down to access all the values required Hj Saee Ha r w Tune Vel Loop ATC x xis Pro ertie Du Categories General ete E Motor Parameters to be read each cycle Model Motor Feedback Scaling Hookup Tests Polarity P Autre T axis A Load me Fin Friction iS Position Loop Axis1 Pos Velocity Loop aaa Acceleration Loop Torque Current Loop mn ora mn Status Faults amp Alarms Tan Useful Pens Tab Tips Here are some useful tips
60. dwidth in band they are automatically suppressed when load observer is applied with the recommended out of box settings Otherwise they can cause classical instability that generates an audible low pitch growling noise and requires detuning of control loop gains Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 b High Frequency HF Resonances HF resonances are above the Torque Loop Bandwidth Because they are outside the closed loop bandwidth out of band they are suppressed using torque loop notch filters It is often left to the user to identify the resonant frequencies and manually configure the notch filters HF resonances typically generate an audible high pitch squealing noise If there are more HF resonances than there are notch filters available a torque loop low pass filter can be applied to suppress resonances at the highest frequencies Adaptive tuning addresses HF resonance by automatically configuring these filters A last resort is detuning control loop gains until resonances go away c Mid Frequency MF Resonances When resonances occur in the neighborhood of the Torque Loop Bandwidth torque loop notch filters are applied at frequencies close to the closed loop bandwidth This close proximity allows phase lag generated by the notch filter to interfere with closed loop dynamics and cause instability As a result control loop gains must be lowered to restore stability or notc
61. e c LM IM MM ER UE 71 SCOS DENO ae ELenc e M M UE LEE P Ed 72 EtherlNet IP Ditives s oct conn acdee dene RP E OR boce iind 73 Low aS SE tet oett bad tet seer E nap et pu E 73 Sercos D EIVOS dues ds eteliewv petente DE dudes iude td ates 74 EtherNet IP Drives sseeeeeeeeeeee RR Hh nnn 75 Ether Net TP Drive Eae Filters ss btt otio hederae in po ne 75 Friction CCofnpensatiOfises cos adne da Eus Bacon ao Dea ET dea eA 76 SEALIC FIC CIO Nase wis ne cst ah acts ULM LI LE ELM EE 76 Sliding EEICEIONG S no edis a ERU o dup dida ce quiu E 77 Viscous F riCon a Seb ook aus ai ine eee a iode gi Backlash Compensation saos edesig uat VE em eter E VUE A Rd 78 SEECOS TOT OS oos natu E A s ret uuu e AMI Pct 79 PeherN etl P DENV6eSCccunotcoeeo EE es wiwnsd Ea TS 80 Chapter 6 Control LOOP eerren a E a ees 81 PULOLUMING 1o Erde uasdeulce suom Dalm ase bet did on bite corey 81 Tunine Methodus bvasebe ben ANE e eaten ELS tenes 81 How le Work zat street DEAS aec esdube rece easet 84 Mental Mune NECEM 84 Dire ERR aes oa eats ne ok E A ROR ba eee eee 87 Feedback Filter and Low Pass Filter 0 cece eee eee 88 Resonator and Notch Filter 0 0 cc ccc cee cence eee a eeee 88 Appendix A Example T irere Da en tE PD FEWER SEA Itb anaes 91 EXAMPleD poorid aaan aho hase MiD Keats du r Lui ba ib baaded 92 REE on o eae EEE AEA T ute uES RUD E A EET 93 Appendix B Trend Properties Dialog BOXSorss annus bust tate RUE Paste s dpa id 95 Mane
62. e low and Frequencies Status high frequency limits with magnitudes above the tuning threshold Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state Torque Notch Filter Frequency Below Limit Status This bit is set when resonances are identified below the low frequency limit with magnitudes above the tuning threshold Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state Rockwell Automation Publication MOTION AT005B EN P November 2015 31 Chapter 1 32 Background Parameter Name Bit Description Torque Notch Filter Frequency 4 This bit is set when resonances are identified above the high frequency limit Above Limit Status with magnitudes above the tuning threshold Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state Adaptive Tune Gain 5 This bit is set when the gain scaling factor is not equal to one indicating that Stabilization Status adaptive tuning is controlling the low pass filter and adjusting servo loop gains to stabilize the system Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state These status bits let you create custom ladder logic to trap errors debug and react to changes This is useful for condition monitoring diagnostics and preventative maintenance purposes The following table describes when output para
63. e the drive Click the Autotuning window Gain Scaling 8 Enable Velocity Integrator In Position lode Autotuning 5 Enter the Travel Limit This is the maximum Travel Limit the motor does not necessarily move this distance 6 Check the appropriate Tuning box depending on the drive mode Autotuning 192 168 1 70 E xj 1 Enable switch should be enabled 2 During auto tuning motor can operate resulting in mechanical part to move or rotate Do not touch it 3 Select input parameters for auto tuning 4 Hit Start Auto tuning button when ready 5 Verify return parameterz in dialog box before accepting it 6 Accept or decline new parameters 7 Home pozition will be lost Travel Limit 1 0 Uzer Unitz w Position Tuning Velocity Tuning Start NN NNI e Ifusingan indexing mode or a positioning mode check Position Tuning e Ifusing a velocity mode check Velocity Tuning 7 Click Start IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have safeguards in place to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion Rockwell Automation Publication MOTION AT005B EN P November 2015 Kinetix 300 Drive Tuning Chapter 6 8 Click Yes to accept the tuned gains Autotuning TERR ES 1 Enable switch should ba enabled 2 Dunng auto tuning motor can operate resu
64. e the limits slightly and try again The load ratio torque scalar and system acceleration are then calculated upon successful completion of the bump test Figure 40 Sercos Drive Autotune Bump Test Results General Motion Planner Units Diree Motor Motor Feedback Aux Feedback Conversion Hormg Hookup Tune Dynamics Gare Output Limits Difset Fault Acton Tag Motor Inertia 0 000044 Kgm 2 Load Inatia Ratio 20 0 Load Inetia M oor Inertia Tonque Force Scaling O 36734396 Rated Position Urits s 2 System Acceleration 272 22443 Position Units s 2 at 100 Rated Gain Calculation The remaining parameters on the Tune tab of the Axis Properties dialog box are used to calculate control loop gains The damping factor z 0 8 by default Application Type The Tune check boxes determine which integrator and feed forward gains are enabled and given a non zero value Figure 41 Sercos Drive Autotune Gain Selection Parameters General Motion Planner Uruts Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gans Output Limata Offset Fault Actions Tag Tavin 20 Position Units Speed 10 0 Position Units s DANGER Starting tuning procedure with controller Temque Force 80 0 r Rated regen vohis Mode Direction Forward Unidirectional Damping Factor 08 Tune Position Error Integrator C Velocity Error Integrator C Friction Compensation _ Velocity Feedforward _ Accel
65. easuring Load Characteristics Motor a Model Si Custom 2 Perform Tune Motor Feedback L Scaling nim Medum wv i espanse Hookup Tests led Polarity Coupli Compliant Y Loop Parameters Tuned Customize Gains to Tune _ Position Integrator B andvadth Velocity Integrator Bandwidth v Velocity Feedfonward Acceleration Feedforward Velacity Loop Acceleration Loop Tomue Low Pass Filter Touque Curent Loop f Drive Parameters gt Position Units Parameter List Status i Position Lngs s Faults Alans Rated Tag Set the Travel Limit and Speed based on the physical limits dictated by the mechanics of the application Start with Torque Force 50 If the bump test fails change the limits slightly and try again The load ratio system inertia torque scalar and system acceleration are then calculated upon successful completion of the bump test Figure 44 EtherNet IP Autotune Bump Test Results General mC haracteristics of Motor Load Motor Model Load Inertia Mass Motor Feedback Load Coupling Compliant v Scaling M v R Hookup Tests Msi du Polarity Load Ratio 20 0 Load Inertia Motor Inertia n Motor Inertia 0 000044 Kgm 2 c rl Backlash Compliance Friction Observer Inertia Mass Compensation Position Loop System Inertia 0 3038342 x Rated Rev s 2 Velocity Loop Advisor Loop System Acceleration 329 12686 Rev s 2 100 Rated You can select whe
66. ence 32 493298 32 293671 Axis1 PositionError 0 000122 0 000117 1 0 000000e 7 32 493298 Tuning Friday October 09 2015 4 000014 32 293671 0 000122 0 000117 2 45 23 880 PM 2 45 25 880 PM e Foran EtherNet IP drive a typical range of values for the position integral gain is given 0 lt K lt K 4 Rockwell Automation Publication MOTION AT005B EN P November 2015 67 Chapter4 Manual Tuning Axis1 CommandPosition 4 000018 0 000000 1 Axis1 TorqueReference 37 952499 35 075005 Axis1 PositionError 0 000070 0 000077 9 000000 37 952499 Tuning Friday October 09 2015 4 000018 35 075005 0 000070 f 0 000077 2 58 37 514 PM 2 58 38 614 PM e ForaSercos drive a typical range of values for various gains are given 0xKg 100 A 0 lt Ky lt K 4000 8 Stop the trend 9 Stop the drive with an MAS instruction or motion direct command 10 Disable the drive with an MSF instruction or motion direct command 11 With the drive disabled adjust the Position Error Tolerance and Velocity Error Tolerance to values that are acceptable to the application and that result in a fault when required 68 Rockwell Automation Publication MOTION AT005B EN P November 2015 Compensating for High Frequency Resonan
67. er application to create a motion axis e Understanding how control loops work in motion control applications Kinetix servo drives implement an acceleration torque loop which is nested within a velocity PI control loop which is nested within an outer position PI control loop Each element in Figure 1 is described in subsequent sections Figure 1 Kinetix Servo Control Loop Structure Position Feed Command Forwards Torque Torque Loop Filters Scalar Position Velocity Torque Loop Loop Estimate Torque Load Velocity bare Estimate Feedback Filter Position Feedback This type of control structure includes these advantages e Precise control of position velocity and torque e Ability to switch between position velocity and torque modes without changing tuning gains e Simple Inside Out tuning described in Manual Tuning on page 61 The blue elements in Figure 1 represent features that are different across drive platforms Lead lag Filter LL The lead lag filter is new in drives that support integrated motion on EtherNet IP and is not present in Sercos drives See EtherNet IP Drive Lag Filter on page 75 for more information about the lead lag filter Position Command and Feedforward Commands The fine interpolators in EtherNet IP drives generate a third order position command a second order velocity feed forward and a first order acceleration feed forward In Ser
68. eration Feedfomwarnd Output Fiter 44 Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 There are many combinations of integrator and feed forward gains to enable The following table shows some common applications and which integrator and feed forward gains are enabled for each Table 11 Sercos Drive Gain Selection Based on Application Type Application Type Applications Ka Ka Integrator Hold DH Kar moo meemmm p Converting Printing Web Tracking Flying shear Coordinated motion Rotary knife Packaging Pick and place Indexing Robotics Palletizing Point to Point Conveyors Constant Speed Line shafts Cranks Positioning High performance position control v fw J Autotune calculates the control loop gains when the controller is online and the Start Tuning button is pressed The position and velocity integrators are calculated with non zero values if they were selected on the Tune tab of the Axis Properties dialog box Velocity Proportional Gain Kj 20 Ty 4z Position Proportional Gain Kj Kj 427 Velocity Integral Gain K 0 K 4000 Position Integral Gain Ky 0 ka 4000 Figure 42 Sercos Drive Autotune Gain Relationships z 0 8 In Sercos drives damping factor affects loop spacing but not integrator spacing A loop spacing of Az is sufficient for rigid loads but can be too hot for most loads which are classified
69. erver is enabled on the Observer tab of the Axis Properties dialog box autotune performs the following control loop gain calculations for a rigid load coupling Note that Kop K for all autotune rules Figure 47 EtherNet IP Drive Autotune Rigid with Load Observer Gain Relationships Compliant Coupling Because compliant loads constitute such a large class of systems all the gains are reduced by a factor of R 1 to achieve stability under any circumstance As a result autotune performs the following control loop gain calculations The damping factor z 1 0 by default Figure 48 EtherNet IP Autotune Compliant without Load Observer Gain Relationships Default 2210 Most of the time these gain settings are too low and they can be manually increased to boost motion performance For more information see Manual Tuning on page 61 When load observer is enabled on the Observer tab of the Axis Properties dialog box autotune performs the following control loop gain calculations Note that Kop Kop for all autotune rules Figure 49 EtherNet IP Drive Autotune Compliant with Load Observer Gain Relationships 1 1 l 1 p 4z R 1 69 9 Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 Perform Tune After choosing settings from the Application Type Loop Response and Load Coupling pull down menus you are ready to perform an autotune while online with the control
70. ficult axis from a stable initial state Other requirements include the following e Start with a set of gains that produces stable operation e The load is attached to the motor while tuning e The drive uses a nested velocity position loop structure for example Sercos and EtherNet IP drives If you have just configured the axis with autotune or out of box settings outlined in the previous chapters but you still require more performance skip this section and proceed to Tune the Velocity Loop on page 63 If your mechanical load is unstable or your control loop gain values are undesirable then start with this section However we advise that you first attempt the recommended steps that are outlined in the previous chapters Out of Box Tuning on page 33 and Autotuning on page 43 as they will yield stable results Follow these steps to bring the axis back to an initial state with default settings 1 Go offline with the controller in the Logix Designer application 2 Open the Axis Properties dialog box Rockwell Automation Publication MOTION AT005B EN P November 2015 61 Chapter4 Manual Tuning General Motor Model Motor Feedback Scaling Hookup Tests Polarity Autotune Load Backlash Compliance Friction bserver Position Loop Velocity Loop 3 Reset the axis configuration back to default settings by using either of these methods e Set the motor type to none and then reselect the motor by its
71. h Compensation feature Mechanical backlash is a common problem in applications that use gearboxes and inexpensive couplings This problem happens because until the input gear is turned to the point where its proximal tooth contacts an adjacent tooth of the output gear the reflected inertia of the output is not felt at the motor In other words when the gear teeth are not engaged the system inertia is reduced to the motor inertia Figure 60 Representation of Backlash Inertia J Motor Inertia 4 Load Motor Inertia Backlash Position Distance Rockwell Automation Publication MOTION AT005B EN P November 2015 Filters and Compensation Chapter 5 If the velocity control loop is tuned for peak performance with the load applied the control loops are under damped at best and unstable at worst in the condition where the gear teeth are not engaged In the worst case scenario the motor and the input gear oscillate wildly between the limits imposed by the output gear teeth The result is a loud buzzing sound commonly referred to as gearbox chatter when the load is at rest If this situation persists the gearbox will prematurely wear out To prevent this condition the conventional approach is to detune the velocity loop so that the axis is stable without the gearbox load applied Unfortunately system performance suffers With a Backlash Stabilization Window value commensurate with the amount of backlash in the mechan
72. h a known load ratio R and resonant frequency Fr a pole is placed at the anti resonant frequency and a zero is placed at the resonant frequency using the following calculations K 1 sqrt R 1 F KxFr However using this filter can make the drive more sensitive to disturbances We recommend using the Load Observer with Velocity Estimate mode to compensate for load compliance and disturbances e When K 1 the filter is off We recommend this mode of operation e When K gt 1 the filter is a lead lag This has been used to boost velocity or acceleration loop bandwidth Friction compensation applies a compensating directional torque or force to the motor to overcome the effects of friction in a mechanical system thus reducing the control effort required Individual attributes have been defined to support compensation for static friction sliding Coulomb friction and viscous friction A compensation window attribute is also provided to mitigate motor dithering associated with conventional friction compensation methods Static Friction It is not unusual for a mechanical load to have enough static friction commonly called sticktion where the mechanical load refuses to move even with a significant position error Position integral gain can be used to generate enough drive output to correct the error but this approach may not be responsive enough for some applications An alternative is to use Static Friction Compensation to
73. h filter width can be decreased to reduce the impact of phase lag if the drive supports this feature Similarly torque loop low pass filters impact stability when they are applied at frequencies as low as three to five times the closed loop bandwidth because they generate more phase lag than notch filters As a result low pass filters should only be applied if you run out of notch filters and should only be reserved for resonances at the highest frequencies Adaptive tuning addresses MF resonance as well 2 Load Side Resonances Even with a tightly controlled motor shaft and all motor side resonances suppressed the end effector may still oscillate at a few Hz through a compliant connection to the motor These resonances typically cannot be monitored through the motor encoder This is common in applications with robots cranes liquid sloshing laser cutting and other cantilevered loads End effector vibration suppression requires one of the following techniques e Determine the load oscillation frequency with a stopwatch and apply a command notch filter at that frequency if the drive supports this feature e Determine the load oscillation frequency with a stopwatch and modify the input CAM motion profile to be smoother and without load oscillation frequency content e Place a feedback device on the load in dual feedback mode How It Works Adaptive tuning is always running in the background to detect motor side resonances Every fe
74. hapter 5 70 Filters and Compensation 3 e Ifan audible high frequency resonance is present during the move sequence use an FFT smart phone or tablet application to identify the dominant resonant frequencies This frequency is shown as the largest peak in the iAnalyzer Lite example below 107 508 627 3H2 D S 5c Full Version resonances are below the torque loop bandwi in Hz and a low pitc If below the torque loop bandwidth in Hz and a low pitch growling sound is present then instability is present and you must decrease your control loop gains before continuing with the following steps For a Sercos drive click the Output tab in the Axis Properties dialog box and do the following a Check the Enable Notch Filter Frequency box b Set the Notch Filter Frequency to the resonant frequency with the largest magnitude If multiple resonances have nearly the same magnitude set the Notch Filter Frequency to the lowest resonant frequency c Ifthe problem persists set the Notch Filter Frequency to the next highest resonant frequency d If the problem persists select the Enable Low pass Output Filter box set the Low pass Output Filter Frequency to 2000 Hz and decrement it until the ringing stops or until instability occurs If instability occurs detune control loop gains until the system stabilizes e As you change control loop gains or the low pass filter bandwidth resonant frequencies may shift or change As a res
75. he metric that makes the most sense is Bandwidth that is measured in Hz Servo Loop Bandwidth 12 Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Figure 7 System Gain versus Frequency Gain dB Bandwidth Hz Frequency Hz Position velocity and torque loop bandwidth indicate the respective performance of each loop in a servo drive Higher bandwidth improves transient response decreases error and makes the motor performance stiffer The following figure shows how bandwidth affects actual response with feed forwards disabled solid compared to its command motion profile dashed Figure 8 How Bandwidth Affects Transient Response ALL L 3 Higher Bandwidth These factors affect Servo drive bandwidth ee s i Lower Bandwidth e Feedback resolution higher is better e Motor to Load inertia ratio lower is better e Drive loop update rate higher is better e Load compliance rigid coupling is better e Drive Model Time Constant lower is better See Drive Model Time Constant on page 15 for more information on this topic The drive motor and feedback device have a significant impact on the bandwidth that can be achieved on an axis through tuning Table 1 shows bandwidth values for various drive and motor combinations Each has different loop update rates and feedback types Rockwell Automation Publication MOTION AT005B EN P November
76. hem The autotune method described below works well for most applications The control loops within a Kinetix 300 servo drive are shown below Figure 64 Kinetix 300 Drive Control Loops Position Loop used in Indexing Mode a Velocity Command Position Gain Position Saturation Integrator Position D Gain Position P Gain Filter 1 Filter 2 Target Velocity Wey Error D Velocity Gain Velocity m Wu N Current Command Integrator EM Sv 2 11 GainScaling LPF Feedback Low pass Filter Autotuning Saturation by Scaled Current Limit Velocity P Gain Velocity Feedback Velocity Loop used in Indexing Velocity and Torque Modes Depending on the load it is generally beneficial to autotune without the load attached to achieve good control of the motor This provides a stable motor before the load is attached in the case of a compliant load type Tuning Method Follow the steps below to perform an autotune on a Kinetix 300 drive 1 Type in the IP address of the drive in Internet Explorer software and in the General dialog box Rockwell Automation Publication MOTION AT005B EN P November 2015 81 Chapter 6 82 Kinetix 300 Drive Tuning 2 Set the drive mode to Auto Tune Description Value Drive Mode EtherNetlP External Reference Current Limits Auto Tune EtherNetiP External Reference Master Gearing GETE S F 1 ad a fuam Aad Mies atl aoe Current Limit 3 Enabl
77. ical system the backlash stabilization algorithm is very effective in eliminating backlash induced instability while still maintaining full system bandwidth The key to this algorithm is a tapered K profile shown in the following figure that is a function of the position error The reason for the tapered profile as opposed to a step profile is that when the position error exceeds the backlash distance a step profile creates a very large discontinuity in the torque output This repulsing torque tends to slam the motor back against the opposite gear tooth and perpetuates the buzzing effect The tapered profile can be qualified to run when only the acceleration command or the velocity command to the control loop structure is zero that is when not commanding motion that engages the teeth of the gearbox Figure 61 Backlash Stabilization Window Effective K j f Motor Inertia Load Backlash Position Error Distance Properly configured with a suitable value for the Backlash Compensation Window this algorithm entirely eliminates the gearbox buzz without sacrificing any servo performance The Backlash Compensation Window parameter determines the width of the window over which backlash stabilization is applied In general this value is set equal to or greater than the measured backlash distance A Backlash Stabilization Window value of zero effectively disables this feature Sercos Drives For a Sercos drive the backlash related va
78. igure 38 EtherNet IP Drive Out of Box Gain Relationships with Load Observer When the low pass filter is enabled set it to a value greater than 5 times Kp or Kop whichever is larger This prevents additional phase lag created by the low pass filter from being introduced into the system causing instability When the load observer is enabled the low pass filter default setting is given Low pass Filter Bandwidth LP 5x Kop EtherNet IP Drive Recommended Settings This method of setting control loop gains applies to Kinetix 5500 Kinetix 5700 and Kinetix 6500 drives It works for unknown loads or when an autotune is not performed It uses load observer and produces a relatively high level of performance in 9096 of motion applications Most of the time there is no need to perform an autotune procedure or further optimize gain settings Therefore it has become the recommended out of box setting for EtherNet IP drives Follow these steps to configure the drive for high performance right out of the box 1 Click the Autotune tab in the Axis Properties dialog box Rockwell Automation Publication MOTION AT005B EN P November 2015 Out of BoxTuning Chapter 2 a From the pull down menus for Application Type Loop Response and Load Coupling choose Custom Medium and Rigid settings respectively b Verify that only the Velocity Feedforward box is checked General Tune Control Loop by Measuring Load Chatactenstics Hoto
79. instability Rockwell Automation Publication MOTION AT005B EN P November 2015 17 Chapter1 Background Load Observer Feature 18 The load observer feature is a control loop inside the drive that estimates the mechanical load on the motor and compensates for it This allows the control loops to treat the motor as if it is unloaded and relatively easy to control As a result the load observer automatically compensates for disturbances and load dynamics such as sudden inertia torque changes compliance backlash and resonances that are within the load observer bandwidth Benefits You can use load observer with out of box control loop gains where the load is unknown and thus the Load Inertia Ratio 0 or with autotuned control loop gains where the Load Inertia Ratio is known or calculated by performing an autotune procedure When the load observer is enabled with the recommended out of box control loop gains the load observer does the following e Provides relatively high performance motion control without tuning e Eliminates periodic retuning to account for machine wear over time e Automatically compensates for changing vibration and resonances that are within the load observer bandwidth e Eliminates periodic identification of in band resonances to compensate for them When used with autotuned control loop gains the load observer does the following e Increases system bandwidth e Reduces tracking errors so line speeds
80. is to where you can comfortably see one or more cycles of the movements You can always zoom in by clicking and highlighting the area Name Genesi Diis Pens is Ye Chart tine range Start date 4 13 2013 Tii Start time 2 25 01 PM Display ophons v Display scale Display date on scale 4 Major grid lines 0 Minot grid lines B Grid color 98 Rockwell Automation Publication MOTION AT005B EN P November 2015 Creating Trends for Tuning Appendix B Y Axis Tab The Y Axis tab has some important settings that can be useful in different situations Name General Display Pens XAxis Y Axis Template Sampling Start Trigger Stop Trigger Minimum maximum value options Automatic best fit based on actual data Preset use min max setting from Pens tab Custom Minimum value Maximum value Scale options Isolated graphing U isolation All pens on same scale J Display scale Decimal places 9 Each pen on independent scale i Scale using pen V Display grid lines 4 Major grid lines Grid color 0 Minor grid lines Scale as percentage e Value options clicking Automatic is the simplest however when tuning specific values it can be more useful to click Preset with the Min and Max values you have previously set e Isolated graphing checking this box displays all the pens in a time chart format This is useful when plotting digital signals against motion Also when used wi
81. k Aux Fee Homing Hookup Tune Dynamics Gains Outpur Limits Offset Friction Compensation Friction Compensa Window Reversal Offset Stabilization Windally Velocity Offset Torque Force Offs 2 Verify the autotune direction is bidirectional and that Torque Offset is checked as shown in the figure below EF AAA FIVE Al General Motion Planner Units Drive Motor Motor Feedback Aux Feedbe Homing Hookup Tune Dynamics Gains Outpu Limits Offset Fa Travel Lint 10 0 rev Speed 00 rev s DANGER Th d procedure ma Totque Force 100 0 Rated E 4 seed Damping F actor 8 Tune Position Erorintegrator Velocity Error Integrator Friction Compensation Nelociy Feediomead Acceleretion Feedtorward CIV Torque Offset Output Filter 3 Execute the autotune on the axis See Start Tuning on page 46 for details Set the gains that need to be included for the application based on Jable 11 on page 45 Rockwell Automation Publication MOTION AT005B EN P November 2015 107 AppendixD Vertical Axis Tuning EtherNet IP Drives 1 Set the Torque Offset value to zero The Torque Offset is calculated during autotune Polarity Load Ratio 0 0 Load Inerts Motor Inertia 0 000044 Kg m 2 Load h 000044 Compliance Friction Observer Inertia Mass Compensation Position Loop System Inertia 0 014468295 Rated F Velocit vu Loe System Acceleration 691
82. lace to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion 66 Rockwell Automation Publication MOTION AT005B EN P November 2015 Manual Tuning Chapter 4 b Execute the move profile Start the move cycles slowly at approximately 2 3 of the application s speed with a period of 4 seconds increasing the speed to match your application requirements 3 Run the trend Incrementally increase Kip while observing a reduction in the Position Error trend You may need to stop motion after each modification of Kp Axis1 CommandPosition 4 000014 Tuning Friday October 09 2015 4 000014 T T T T T T 7 0 000000 4 i i i i i i i y Axis1 TorqueReference 35 861374 39 664814 Axis1 PositionError 0 031873 0 031876 9 900000 35 861374 39 664814 0 031873 0 031876 2 43 12 536 PM 2 43 14 636 PM 5 Continue increasing K until you hear an audible low pitch growling sound or until oscillation occurs in the Torque Reference 6 Decrease Kig by dividing it by two 7 See Table 11 on page 45 to determine if setting other position loop gains are required for your application e Foran EtherNet IP drive a typical range of values for velocity feed forward gain is given 0 lt K lt 100 Axis1 CommandPosition 4 000014 10 000000e 7 y Axis TorqueRefer
83. ler 1 Click the Start button on the Autotune tab of the Axis Properties dialog box For variable inertia loads perform an autotune at the point of lowest mechanical inertia 2 Ifyou want to manually calculate the Load Ratio clear the Measure Inertia using Tune Profile checkbox and enter the minimum load inertia on the Output tab General BiT une Control Loop by Measunng Load Charactenstics Motor Model usi Custom v Perform Tune Motor Feedback ius Scaling Pie Hedum wv Hookup Tests i3 I tu Polarity oun Comphart v Loop Parameters Tuned Autotune 5 i E Load Customize Gains to Tume Backlash Position Integrator Bandwidth 3 Hz etm Velocity Integrator Bandwidth VelocityLoopBandwidth Hz ncb bserver v Velocity Feedfonvard nie Loop C Acceleration Feedforward elocity Loop Acceleration Loop C Torque Low Pass Filter Torque Curent Loop Planner 3 Wait for the tuning to complete Click Accept Tuned Values 5 lest the drive and observe mechanical performance and stability a Create a move profile in the Logix Designer application to observe the behavior of the mechanical load while tuning See Appendix A for more information on Creating Move Profiles for Tuning An example CAM table for an MATC instruction is shown below Linear Cubie lunew lukat Lr iube Linear new Rockwell Automation Publication MOTION AT005B EN P November 2015 55 Chapter3 Aut
84. ll Automation Publication MOTION AT005B EN P November 2015 27 Chapter1 Background In the following figure the parts of the control loop structure affected by Tracking Notch Filters are highlighted in blue Figure 27 Tracking Notch Filter Configuration Position Feed Command Forwards Position Loop Velocity Loop Estimate Torque Load Velocity Veloci y Estimate Feedback Fs Filter Position Feedback Gain Stabilization In modes with Gain Stabilization adaptive tuning does two main things First it enables and tunes the low pass filter to suppress resonances if any are identified above the low frequency limit Here the Torque Low Pass Filter Bandwidth Estimate is applied to the torque low pass filter instead of the Torque Low Pass Filter Bandwidth that is visible on the Compliance tab of the Axis Properties dialog box The bandwidth estimate is incrementally decreased from its default value until the identified HF resonances are suppressed or until a LF resonance or instability occurs EJ Load Adaptive Tuning Adaptive Tuning Configuration Gain Stabilization ha Friction Torque Notch Filter High Frequency Limit 2000 0 Hertz bserver Torque Notch Filter Low Frequency Limit 296 33984 Hertz Position Loop Torque Notch Filter Tuning Threshold 00 Motor Rated H Velocity Loop Second adaptive tuning detunes control loop gains to suppress any remaining resona
85. lting in mechanical pari MA masa Af Alala fia DAT IA Important She xi Ci AutoTuning completed with Succes Do yeu like to accept lollewing coefficients Velocity P Gain 8448 85 Velooty I Oain 1584 61768 Gain Scaling 7 Postion P Gam 213 39434 Foston Gain 0 0 tert 9 Enable the drive and use the drive mode to determine if the drive is stable Some values that you can modify are described below and can be accessed from the Dynamics dialog box 11192168 170 Motor a Description Value Units Min enera Communication Velocity P Gain 3165 8632812 0 0000 Ethernet f Vel 1 258697 EtherNeviP CIF elocity I Gain 84 2586975 0 0000 IO Position P Gain 2192 2597656 0 0000 Digital IO Position I Gain 0 0000 0 0000 Analog IO r Limit Pozition D Gain 359 1798706 0 0000 Velocity Limits Position Limit 0 0000 RPM 0 0000 Position Limits lt Dynamics Gain Scaling 210 16 Indexing Enable Velocity Integrator In Position Mode Homing Tools Autotuning Monitor Faults SetDefault Gains Feedback Filter ot Feedback Filter Time Constant 2 0000 mz 1 0000 Filter T Type pe Filter 2 Type px e Gain values are loaded by default and are based on the motor nameplate and drive size These values can change after an autotune is performed e Gain Scaling
86. lues are located on the Load tab of the Axis Properties dialog in the Logix Designer application Rockwell Automation Publication MOTION AT005B EN P November 2015 79 Chapter5 Filters and Compensation Figure 62 Sercos Drive Backlash Compensation Attributes XD Axis Properties Axis General hdotion Planner Units Dmve Motor Motor Feedback Aux Fee Homing Hookup Tune Dynamics Gains Output Limas Offset Fnchon Lompenzalion Fiction Compensation 0 Ma Window 0 0 Position Units Backlash Compensation Reversal Offset an Position Units Stabilization Window 0 0 Position Uritz EtherNet IP Drives For an EtherNet IP drive the backlash related values are located on the Load tab of the Axis Properties dialog box in the Logix Designer application Figure 63 EtherNet IP Drive Backlash Compensation Attributes Axis Properties Axis1 Categories General Backlash Compensation Motor P Model Reversal Offset 0 0 Position Units Motor Feedback Compensation Window 0 0 Position Units Scaling Hookup Tests Polarity Autotune Load Backlash Compliance Friction 80 Rockwell Automation Publication MOTION AT005B EN P November 2015 Control Loops Encoder Feedback Target Position Position Error Chapter 6 Kinetix 300 Drive Tuning This chapter provides instructions to perform an autotune and explains the Kinetix 300 drive control loops and filters and how to use t
87. mation on how to tune the load observer feature see Out of Box Tuning on page 33 and Autotuning on page 43 The following table summarizes the primary difference between the two tuning modes Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Table 6 Sercos Load Observer Tuning Mode Differences Tuning Mode Description Rad s Out of box or unknown load Load inertiaRatio 0 Load Observer Bandwidth Kop 4x Velocity Proportional Gain Kyp Autotuning or known load Load Inertia Ratio gt 0 Load Observer Bandwidth Kp Velocity Proportional Gain Kyo EtherNet IP Drive Configuration This section applies to the load observer feature in Kinetix 5500 Kinetix 5700 and Kinetix 6500 drives The load observer configuration is greatly simplified in EtherNet IP drives compared to Sercos drives because it is natively supported by an interface in the Logix Designer application Click the Observer tab in the Axis Properties dialog box Here the load observer mode can be selected with the Configuration pull down menu See Table 2 on page 19 for descriptions of each setting If load observer is enabled the recommended Configuration setting is Load Observer with Velocity Estimate for positioning applications Access to Load Observer Bandwidth Kop and Load Observer Integral Bandwidth K is also shown Typically K 0 Figure 22 EtherNet IP Load Observer Configuration General Load Observer
88. meters get reset to their default value Table 10 Adaptive Tuning Reset Behavior Parameter Name When Reset to Default Value Torque Notch Filter Frequency Estimate Transition to Disabled or Gain Stabilization modes Torque Notch Filter Magnitude Estimate A resonance is not identified Torque Low Pass Filter Bandwidth Estimate Transition to Disabled or Tracking Notch Filter modes Adaptive Tuning Gain Scaling Factor Transition to Disabled or Tracking Notch Filter modes Rockwell Automation Publication MOTION AT005B EN P November 2015 Sercos Drives Chapter 2 Out of Box Tuning Out of box refers to default control loop gain settings that are pre configured for a new axis when it is created Since the load is unknown at this point the motor is assumed to be unloaded and the load ratio R 0 However when the load is known or an autotune has been performed the control loop gains are configured for a load ratio R gt 0 This is the primary difference affecting out of box and autotuning rules Thus the term out of box implies R 0 and the term autotune implies R gt 0 In this chapter the sections on gain calculation describe how gains are currently calculated in released product when a new axis is created However the sections on recommended out of box settings proposed in this chapter should be used as a starting point when commissioning a new axis They often yield satisfactory motion performance and no further tu
89. mpensation value is applied A Friction Compensation Window value of zero effectively disables this feature A non zero Friction Compensation Window effectively softens the Static Friction Compensation as it is applied to the torque reference and reduces the dithering and hunting effects that it can create This feature generally lets higher values of Static Friction Compensation to be applied resulting in better point to point positioning Sliding Friction Sliding friction or Coulomb friction by definition is the component of friction that is independent of speed as long as the mechanical load is moving Sliding friction is always less than static friction for a given mechanical system The method of compensating for sliding friction is basically the same as that for static friction but the torque level added to the torque reference signal is less than that applied to overcome static friction and is determined by the Sliding Friction Compensation attribute Sliding Friction Compensation is applied only when the motor is being commanded to move Viscous Friction Viscous friction is defined as the component of friction that increases linearly with the speed of the mechanical system The method of compensating for viscous friction is to multiply the configured Viscous Friction Compensation value by the speed of the motor and apply the result to the torque reference signal Viscous Friction Compensation is applied only when the motor is being
90. nces and stabilize the system Here the following gains are scaled by the Adaptive Tuning Gain Scaling Factor e Load Observer Bandwidth e Load Observer Integrator Bandwidth e Velocity Loop Bandwidth e Velocity Loop Integrator Bandwidth e Position Loop Bandwidth e Position Loop Integrator Bandwidth This means that the actual control loop gains are the values shown in the Axis Properties dialog box multiplied by the gain scaling factor The scaling factor is incrementally decreased from its default value until the system is stable When 28 Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Gain Stabilization is not enabled the scaling factor is reset to its default value of one so that control loop gains are not affected In the following figure the parts of the control loop structure affected by Gain Stabilization are highlighted in blue Figure 29 Gain Stabilization Configuration Position Feed Command Forwards Mechanics Torque Loop Filters Torque scalar B Position Velocity Torque Loop Loop Estimate Torque Load Velocity Veloci l mooy Estimate Feedback Filter Fosition Feedback Gain Stabilization is good for situations where there are more resonances than there are notch filters and for keeping the axis stable Instability and audible noise are caused from the following situations e HF resonances that are
91. nding 96 useful pens tab tips 97 position command 9 position loop block diagram EtherNet IP drives 110 controller 10 manual tuning 66 resonator filter only Kinetix 300 drives 88 S sampling tab to create trends for tuning 100 scale torque into the system 15 Sercos drives autotuning bump test 43 gain calculation 44 backlash compensation 79 block diagram 109 low pass filter 74 notch filter 72 out of box tuning gain calculation 33 Kinetix 6000 drive recommended settings 34 servo loop bandwidth 12 set load observer configuration attribute with IDN messages 103 gains with IDN messages 104 sliding friction compensation 77 static friction compensation 76 Rockwell Automation Publication MOTION AT005B EN P November 2015 T torque scalar 10 15 torque current loop block diagram EtherNet IP drives 112 trend information with value bar for tuning 100 Trend Properties dialog box to create trends for tuning display tab 96 general tab 95 name tab 95 pens tab 96 sampling tab 100 value bar information 100 X Axis tab 98 Y Axis tab 99 trends for tuning created with Trend Properties dialog box display tab 96 general tab 95 name tab 95 pens tab 96 sampling tab 100 value bar information 100 X Axis tab 98 Y Axis tab 99 tune Kinetix 300 drives 81 position loop manually 66 velocity loop manually 63 vertical axis with holding brake CIP drives 108 considerations 106 Sercos drives 107 tuning background 9 V
92. neral Position Loop Motor REC WM Motor Feedback Bandwidth O 9271278 Hertz Scaling Integrator B andvsdth 0 0 Hertz Hookup Tests Polarity Integrator Hold Disabled n Autotune Velocity Feedionwant 1000 x S r Limits E Emor Tolerance 28 610752 Position Units Lock Tolerance 0 01 Postion Ungs Figure 6 EtherNet IP Velocity Loop Gains in the Logix Designer Application General elocity Loop Motor ae m Motor Feedback Bandwidth 3 708511 Hertz Scaling Integrator Bandwidth 00 Hertz Hookup Tests Polarity Integrator Hold Disabled Acceleration Feedioward 0 0 e Limits Velocity Limit Positive 166 66667 Position Units s Velocity Limit Negative 166 66667 Position Units s Error Tolerance 83 41971 Position Units s Use the following equations to convert existing Sercos control loop gains to equivalent EtherNet IP control loop gains K H K pp Sercos E K vp Sercos pp ciP 5 Kn 5 1000 K pi Sercos 1000 K vi sercos Kpi cIp 7 Kvii 2n K pp Sercos 27 K vp Sercos Bandwidth BW is a widely used term that is critical to servo drive performance It is defined as the usable range of frequencies in Hz where the gain through the system is above 3 dB Bandwidth indicates servo drive performance and directly equates to transient response and how fast the servo physically responds to the load There must be a way to qualify performance for different servo axes and t
93. ng 57 out of box tuning 38 Kinetix 6000 drives autotuning 49 load observer gains 21 out of box tuning 34 torque low pass filter bandwidth 22 Kof feedback gain 21 Koi integral bandwidth 21 23 Kop bandwidth 21 23 Kou input gain 21 L lead lag filter only CIP drives 9 load coupling autotuning gains 53 load observer acceleration feedback 22 bandwidth Kop 21 23 benefits 18 configuration attribute set with IDN messages 103 feedback gain Kof 21 gains set with IDN messages 104 how it works 18 input gain Kou 21 integral bandwidth Koi 21 23 Kinetix 5500 and 6500 drive configuration 23 Kinetix 6000 drive configuration 21 modes 19 load observer with velocity estimate mode 10 loop response autotuning gains 53 low pass filter EtherNet IP drives 75 Kinetix 300 drives 88 Sercos drives 74 M manual tuning initialize the axis optional 61 Kinetix 300 drives 84 position loop 66 velocity loop 63 motion system tuning background 9 motor torque constant 10 move profiles for tuning example 1 91 example 2 92 example 3 93 name tab to create trends for tuning 95 notch filter 71 EtherNet IP drives 73 Kinetix 300 drives 88 Sercos drives 72 0 out of box tuning EtherNet IP drives gain calculation 37 Kinetix 5500 and 6500 drive recommended settings 38 Sercos drives gain calculation 33 Kinetix 6000 drive recommended settings 34 P pens tab to create trends for tuning CIP drive trending 97 Sercos drive tre
94. ng and observing the results e Autotuning without a load results in a stable index The Gain Scaling is 7 and there is tracking error present during the index This tracking error is shown below CSCC CI f Uni t IDi M n Se r Unit Time Base 200 ms Div Trigger Ch1 Falling Edge E Trigger Level 5 0 User Units Stop Triggered Set on Top e The drive is disabled and the Gain Scaling is changed to 6 The changed tracking error is shown in the scope trace below MI scope l 9 168 1 70 Time Base 200 ms Div Trigger Level 5 0 User Units Stop Waiting for trigger Seton Top Trigger Chi Falling Edge m Rockwell Automation Publication MOTION AT005B EN P November 2015 Filters Kinetix 300 Drive Tuning Chapter 6 e The Gain Scaling is changed to 5 and the motor becomes unstable e To improve the tracking error Enable Velocity Integrator in Position Mode is checked and shown below v Enable Velocity Integrator In Position lode e The tracking error is minimal and the move profile is being followed as closely as possible The tracking error is shown below Scope 192 168 1 70 Time Base 200 m I De Trigger Ch Falling Edge Trgger Level 50 User Una fa The filters described below are not modified during autotune e The two filters can be used together with Filter 1 in series with Filter 2 e The filters can be the same filter type with different values e See Compe
95. ning intervention is required The following subsections provide information for out of box tuning of Sercos drives Gain Calculation In a Sercos drive the default damping factor is z 0 8 This produces a loop spacing of 4z 2 56 The proportional gains are calculated from the torque loop bandwidth T in units of rad s and the integral gains are set to zero Velocity Proportional Gain K 20x Thy 427 Position Proportional Gain Kap Ky 427 Velocity Integral Gain K 0 Position Integral Gain Ky 0 Figure 35 Sercos Drive Out of Box Gain Relationships Eg 1 L Default 9 The velocity feed forward gain K cand the acceleration feed forward gain K are set to zero by default as well Rockwell Automation Publication MOTION AT005B EN P November 2015 33 Chapter2 Out of Box Tuning Sercos Drive Recommended Settings This method of setting control loop gains applies to Kinetix 6000 drives It works for unknown loads or when an autotune is not performed It uses the load observer available in firmware revision 1 124 or higher and produces a relatively high level of performance in 9096 of motion applications Most of the time there is no need to perform an autotune procedure or further optimize gain settings Therefore it has become the recommended out of box setting for EtherNet IP drives Follow these steps to configure the drive for high performance right out of the box This pr
96. not the low pass filter is set to suppress it and any other HF resonances Finally the system is detuned if one or more of the following conditions exist e The torque notch filter was set to suppress the MF resonance but its width is wide enough or its frequency is close enough to the closed loop bandwidth to cause instability e The torque low pass filter was set to suppress the MF resonance but its bandwidth is close enough to the closed loop bandwidth to cause instability e There are additional un suppressed resonances present Status Bits Adaptive tuning status bits and their descriptions are given in the following table Table 9 Adaptive Tuning Status Bits Parameter Name Bit Description Torque Notch Filter Frequency This bit is set when resonances are identified between the low and high Detected Status frequency limits with magnitudes above the tuning threshold Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state Torque Notch Filter Tune Unsuccessful Status This bit is set when the tracking notch filters do not eliminate all the identified resonances Otherwise this bit is clear This bit is also cleared when the axis transitions to the Running state or when adaptive tuning transitions from Disabled mode to one of the Tracking Notch modes while in the Running state Torque Notch Filter Multiple 2 This bit is set when multiple resonances are identified between th
97. ns to Tune Backlash Position Integrator Bandesdth Sim iaa Velocity Integrator Bandwadth VelocityLoopBandwidth v Advanced Compensation seii Eiyele Festo e onion Tuned Position Loop C Acceleration Feedionward Veloty Loop je 7 Er Acceleration Loop Torque Low Pass Filter Maxirnurm amp cceleration Po Torque Cunert Loop MaximumDeceleration Po Planner Systeminertia w v Homing A Achons Dave Parameters ive 7g Position Units Parameter List Limit Status Speed 5 0 Postion Unas peces Torque 250 Rated a9 Direction Application Type There are many combinations of integrator and feed forward gains to enable The following table shows some common applications and which integrator and feed forward gains are enabled that is which ones are given non zero values Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 Table 13 EtherNet IP Drive Gain Selection Based on Application Type Application Type Applications Ka Ka Integrator Hold Du Kar iets Converting Printing Web Tracking Flying shear Coordinated motion Rotary knife Packaging Pick and place Indexing Robotics Palletizing Point to Point Conveyors Constant Speed Line shafts Cranks Custom High performance position tracking Pv fo fw J 1 One of many possible combinations available with the Custom setting Loop Response Loop response sets the damping factor z For mo
98. nsating for High Frequency Resonances on page 69 to help determine the resonant frequency of the load Figure 66 Accessing Filters from MotionView Software Type Of Filter 2 Type Low Pass Rezonator Hatch Apply Cancel Rockwell Automation Publication MOTION AT005B EN P November 2015 87 Chapter6 Kinetix 300 Drive Tuning Feedback Filter and Low Pass Filter Figure 67 Filter Locations within the Control Loops Encoder Feedback Position D Gain Target Position Position Error A Velocity Command 9 Position Gain Position Saturation Integrator Position P Gain Target Velocity Gps Error 5 Velocity Gain Velocity i Wa Jg Current Command Integrator EHI omm Saturation by PESE SPSSA ICON Scaled Current Limit Feedback Low pass Filter Velocity P Gain Velocity Feedback e The Low pass filters Filter 1 Filter 2 can be used alone or together to accommodate different application resonance issues Figure 68 Low pass Filter Selection Filter 1 192 168 1 70 x Type Low Pass v Cut off Frequency 800 0000 Hz Apply Cancel e The Low pass filter is a second order bi quad filter that is used to filter resonant frequencies greater than the control loop bandwidth e The Feedback Low pass filter LPF is a first order filter that is used to reject high frequencies coming from noisy feedback sources Resonator and Notch Filter Filter 1 and or Filter 2 can be configured as a n
99. nt for all frequencies The output lags the input up to the notch frequency and leads the input for frequencies above the notch frequency The notch filter is effective in resonance control when the resonant frequency is higher than the control loop bandwidth Like the low pass filter the notch filter works by significantly reducing the amount of energy in the device output that can excite high frequency resonances It can be used even when resonant frequencies are relatively close to the control loop bandwidth That is because the phase lag introduced by the notch filter is localized around the notch frequency For the notch filter to be effective the Notch Filter Frequency must be set very close to the natural resonance frequency of the load For more information on manually setting the notch filter see Compensating for High Frequency Resonances on page 69 Sercos Drives For a Sercos drive click the Output tab in the Axis Properties dialog box Check Enable Notch Filter Frequency and set the Notch Filter Frequency to the desired frequency in Hz 72 Rockwell Automation Publication MOTION AT005B EN P November 2015 Low Pass Filter General Motor Model Motor Feedback Scaling Hookup Tests Polarity Autotuna Load Backlash Compliance Friction bserver Rockwell Automation Publication MOTION AT005B EN P November 2015 Filters and Compensation Chapter 5 Figure 52 Sercos Notch Filter Frequency General Motion Planne
100. ntrol loop bandwidth in units of rad sec However the integral term has a squared relationship to the control loop bandwidth in units of rad sec A factor of 1000 is applied to numerically keep the integral gain in the same range as the proportional gain and attempt to counteract the squared relationship Figure 2 Sercos PI Controllers Parallel Form Position Loop PI Controller Velocity Loop PI Controller This configuration is standard in classical control theory minus the factor of 1000 The following definitions are given for control loop gains of a Sercos drive e K Position Proportional Gain rad s e Ky Position Integral Gain rad s ms e Kp Velocity Proportional Gain rad s e K Velocity Integral Gain rad s ms e Kg Velocity Feedforward 96 e K g Acceleration Feedforward 96 10 Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 These gains can be accessed on the Gains tab of the Axis Properties dialog box in the Logix Designer application Figure 3 Sercos Control Loop Gains in the Logix Designer Application General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions Tag Position Gams i 2 K Manual Adjust Proportionak LEIESSIE l s pp aL Set Custom ains Integral 0 0 1 ms s Kpi Velocity Gains Feedforward Gains i Proportionat 399 105
101. ocedure uses load observer to automatically account for the unknown load As a result you must be familiar with creating an axis in the Logix Designer application and accessing drive IDN parameters 1 Create a new axis with type AXIS SERVO DRIVE 2 Click the Drive Motor tab in the Axis Properties dialog box and add a motor Homing Hookup Tune Dynamics Gains Output Limits Offset Fault Actions Tag General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Amplifier Catalog Number 2094 AM01 v Motor Catalog Number ESBS SET Change Catalog Loop Configuration Paten Sarvo v Drive Resolution 200000 Drive Counts Motor Rev v 3 Click the Gains tab in the Axis Properties dialog box The Velocity Proportional Gain Initial Ke value is used to recalculate all gain values General Motion Planner Unis Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions Tag Position Gai ipa teas i Manual Adjust Proportional 298 6512 1 s Integral 0 0 1 ms s Velocity Gains Feedforward Gains Proportionak MEZ RSTP 1 s Velocity 0 0 Integral 00 1 ms s Acceleration 0 0 x Integrator Hold Enabled v Make the following calculations a Load Observer Bandwidth K Velocity Proportional Gain x 2 56 b Velocity Loop Bandwidth K Kop 4 c Position Loop Bandwidth K K 4 34 Rockwell Automation Publication
102. ommand Forwards Mechanics Torque Torque Loop Filters Scalar Position Loop Torque Load Velocity Velocity Estimate Feedback Filter Position Feedback First the Tracking Notch Filter sets the torque notch filter to suppress a HF resonance with the largest magnitude if one exists Next Gain Stabilization applies the low pass filter to suppress additional HF resonances if they exist This is useful for suppressing more HF resonances than there are notch filters Figure 33 Identifying More HF Resonances than there are Notch Filters Torque Loop Signal Frequency Response Resonance Torque Notch Filter Low Frequency Limit Torque Notch Filter High Frequency Lama Torque Notch Filter Tuning Threshold 10 i0 Frequency Hz Finally if the system is unstable Gain Stabilization incrementally detunes control loops until the system is stable Rockwell Automation Publication MOTION AT005B EN P November 2015 Magnitude Motor Rated Background Chapter 1 A good example is when a MF resonance is identified Figure 34 Identifying One MF Resonance _ Torque Loop Signal Frequency Response Resonance 9 Torque Notch Filter Low Frequency Lima Torque Notch Filter High Frequency Limit al Torque Notch Filter Tuning Threshold Frequency Hz First the torque notch filter is set to suppress it if it is the only HF resonance or if it is the one with the largest magnitude If
103. or change As a result it may be necessary to periodically adjust torque notch filter parameters e Click OK General Compliance Compensation Motor Model Torque Low Pass Filter Bandvadth 0 Heitz Motor Feedback Torque Notch Filter Frequency yee Heitz Scaling i a Hookup Tests Torque Lag Filter Gait Polaiity Torque Lag Filter Bandvadth 0 0 Heitz Autotune Load Backlash Compliance Friction Observer This section applies to the torque notch filter in Kinetix 6000 Kinetix 6200 6500 and early firmware revisions of Kinetix 5500 and Kinetix 5700 drives A notch filter is a filter that passes most frequency signals unaltered but attenuates signals within a specific range of frequencies The following figure shows gain and phase through the filter as a function of the frequency content of a signal passing through it Rockwell Automation Publication MOTION AT005B EN P November 2015 71 Chapter5 Filters and Compensation Figure 51 Notch Filter Bode Plot Bode Diagram o 2 amp a 9C 45 ia 3 M L aa a wa 45 B x 9C i i 10 I Frequency radisec Notch filters typically have a relatively narrow and deep attenuation band Maximum attenuation is achieved at the notch filter frequency The notch filter is second order with an attenuation of approximately 40 dB at the notch frequency As with any filter its output is shifted in phase from the input The shift is prese
104. otch or resonant type filter Both configurations implement band stop filtering to solve certain mechanical compliance problems 88 Rockwell Automation Publication MOTION AT005B EN P November 2015 Kinetix 300 Drive Tuning Chapter 6 The resonator filter has a slightly different transfer function than the notch and guarantees the depth of attenuation Therefore the roll off will be different depending on the gain factor The notch filter has a fixed roll off and the attenuation gain depends on the attenuation bandwidth width of the notch A common problem is torsional resonance due to mechanical compliance between load inertia and motor inertia Consider a long load shaft with an inert load at the opposite end Such a system has a resonant frequency defined by the following equation Figure 69 Equation to Determine Resonant Frequency 1 Ks Fr m Jp Hz where JI load inertia kgm 2 Jm motor inertia kgm 2 Ks total stiffness of coupling and shaft Nm rad Jp Um x JI m 4 JI n 3 1416 Applying the resonant frequency in this configuration will cancel the resonance effectively allowing higher overall gain The resonant filter lets the center frequency and gain to be set independently Rockwell Automation Publication MOTION AT005B EN P November 2015 89 Chapter6 Kinetix 300 Drive Tuning Notes 90 Rockwell Automation Publication MOTION AT005B EN P November 2015 Appendix A Creating Move P
105. otective Equipment PPE Follow ALL Regulatory requirements for safe work practices and for Personal Protective Equipment PPE gt gt gt Allen Bradley Connected Components Workbench DriveExplorer Kinetix Logix5000 PowerFlex Rockwell Software Studio 5000 Logix Designer and Rockwell Automation are trademarks of Rockwell Automation Inc Trademarks not belonging to Rockwell Automation are property of their respective companies Preface Background Out of Box Tuning Autotuning Manual Tuning Table of Contents About This Publication ssseeeeeeee nnn 7 Additional Resources 0 ccc cece cece cece e hn T Chapter 1 Setyo Loop Bandwidth iicet evo opui a rA EEE 12 Darapiug Pactor desg soin ver va Rae E a EE E 14 Drive Model Time Constant eee 15 Lorgues clares si T mT 15 Load Observer Feature ueseeeeeeeeeeeeee ehe nn 18 PCTS PUES ea iste 1 eae toy tein b arts Ada eae AIME DA ERES dU 18 How eWork Lees renmeutiptes eo evexit altos d a ex t Euren 18 Sercos Drive C On MOuraliOn ados vb v edebat n Ls fand 21 EtherNet IP Drive Configuration 2e serre ELO RE RERERG 23 Adaptive Tuning Pe3tilfe oui ounces Ro Vai iet e icu dia uie 24 Dehetiss acti ase eto NATO cae pis inden ine iA Oe doe MERE EAM Dd E 24 Mechanical Resonances eeeesseeeee nne 24 How It WOES on 220 pee oe E da ce Ou ada dcin Cote iu een 25 Chapter 2 DELCOS IVES
106. otuning b Createa trend in the Logix Designer application to monitor Command Position Command Velocity Torque Reference Position Error and Velocity Error See Appendix B for more information on how to Create Trends for Tuning An example trend is shown below E Axist CommandPosition 4 000018 Tuning Friday October 09 2015 0 000840 4 000018 14 20 48 571 PM Axis1 Command elocity 11 999999 11 999993 Axis1 TorqueReference 20 799208 21 043554 Axis1 PositionError 0 001424 0 000840 0 001410 11 899999 7 Axis1 VelocityError 0 225193 0 227838 11 999993 20 799208 21 043554 0 001424 0 001410 E 0 225193 0 227838 1 49 42 407 PM 1 49 44 407 PM c Goonline with the controller and have the drive in a Ready state d Enable the drive with an MSO instruction or motion direct command IMPORTANT Ifthe drive has not been enabled before this step new installation verify that you have safeguards in place to safely remove power from the drive in case of an unstable situation where the drive can produce undesired motion e Execute the move profile Start the move cycles slowly at approximately 2 to 396 of the applications speed with a period of 4 seconds increasing the speed to match your application requirements f Run the trend and observe the mechanical performance g Important Suppress resonances
107. ou manually calculate the Load Ratio use the minimum load inertia if it changes with position or over time Rockwell Automation Publication MOTION AT005B EN P November 2015 57 Chapter3 Autotuning e Otherwise enter the Load Ratio if it is known Categones General BeCharacternstics of Motor Load z Motor Model Load Inertia Mass Motor Feedback Load Coupling Rigid v Scaling char ake Use Load Ratio Polarity Load Ratio 20 0 Load Inertia Motor Inertia Autolune Motor Inertia 0 000044 Kgm 2 Backlash 3 Click the Observer tab in the Axis Properties dialog box a From the Configuration pull down menu choose Load Observer with Velocity Estimate Categories Corral Load Observer Motor Model Configuration Load Observer with Velocity Estimate Parameters Motor Feedback Bandwidth 77 87874 Hertz Scaling Hookup Tests Integrator Bandwidth 0 0 Hertz Polarity Autotune Load Backlash Compliance Friction bse wer b Click Apply The Load Observer Bandwidth and other gains are set automatically 4 Important Suppress resonances a For Kinetix 5500 and Kinetix 5700 drives choose Tracking Notch Filter from the Adaptive Tuning Configuration pull down menu on the Compliance tab in the Axis Properties dialog box Load Adaptive Tuning Adaptive Tuning Configuration Tracking Notch Fiter v Torque Notch Filter High Frequency Limit 2000 0 Hertz Observer Torque Notch Filter Low Frequenc
108. pplication requirements If you have significant overshoot or instability repeat step 3 The response shown in the figure below is acceptable for our application BIET Channel 1 Signal Velocity Command l Scale User Units Div Signal Velocity Feedback MET iw a 998 Scale L gt User Units Div Olsst A amp i t lear i inite Offset 0 000 v User Units Time Base 200 ms Div v Trigger Ch1 Falling Edge v Trigger Level 5 0 User Units Stop Waiting for trigger Set on Top At this point there should be good response with an unloaded motor executing the required profile for the application 6 Disable the drive and attach the load 7 Enable the drive 8 Slowly increase the dynamics of the index while you observe how the load responds If the load is fairly rigid and tightly coupled to the motor the drive will still respond well If the load is not responding well perform an autotune with the load attached Any compliance in the load yields gain values that can be incorrect and misleading Rockwell Automation Publication MOTION AT005B EN P November 2015 85 Chapter 6 86 Kinetix 300 Drive Tuning 9 Dependingon the drive mode you can also continue at this point with the steps defined in Manual Tuning on page 61 for inside out velocity and position loop tuning Also see Compensating for High Frequency Resonances on page 69 Example This example describes changing the Gain Scali
109. r Units Dive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset Faut Actions Tag Motor Inertia 0 000044 kom Load Inertia Ratio 0 0 Load Inertia Motor Inertia Torque Force Scaling 0 01 749257 Rated Position Units s 2 System Acceleration 5715 713 Position Units s 2 at 100 Rated v Enable Notch Filter Frequency Notch Filter Frequency THE Hertz C Enable Low pass Output Filter Sercos IDN P 065 has an impact on how the Low pass Output Filter functions See Table 5 on page 22 for more information EtherNet IP Drives For an EtherNet IP drive click the Compliance tab in the Axis Properties dialog box Set the Torque Notch Filter Frequency to the desired frequency in Hz Figure 53 CIP Notch Filter Frequency Torque Low Pass Filter Bandwidth T Hetz Torque Notch Fiter Frequency 2 Hertz Torque Lag Filter Gair Torque Lag Filter Bandwadth 0 0 Hertz The torque notch filter can also be automatically set in Kinetix 5500 and Kinetix 5700 drives Choose Tracking Notch Filter from the Adaptive Tuning Configuration pull down menu This section applies to the torque low pass filter in Kinetix 6000 Kinetix 6200 6500 Kinetix 5500 and Kinetix 5700 drives A low pass filter passes low frequency signals but attenuates signals above the filter s bandwidth The following figure shows gain and phase through the filter as a function of the frequency content of a
110. rc Brake Rotor Inertia at 24V DC ma 3 Weight approx Mm bi A suppression device kg m Ib in s kg b Wes Siem 23 0 000015 0 00013 0 000026 0 00023 0 000033 0 00029 Motor Cat No MPL A B1510V MPL A B1520U 0 9 8 0 043 053 MPL A 81530U MPL A B210V 12 2 6 140 1 1 8 3 9 1 8 4 0 roay Loaaratio U U L O8G Ineruaaor Autotune Direct Coupled Rotary Load i True Backlash Compliance Friction i i 14024 986 Position Loop i 2776944 5 Velocity Loop 14024 986 Acceleration Loop i 2776944 5 Torque Current Loop 70 833336 Planner E Homing Actions Drive Parameters Fo Parameter List atus Faults amp Alarms Tag MotorDataSource Catalog Number e During tuning and commissioning it may be necessary to control the brake manually See Knowledgebase Article 68763 Kinetix 6000 6500 Manually control the mechanical brake of a servo motor In summary you can write to IDN parameters to manually engage and disengage the brake for both Sercos and EtherNet IP drives 106 Rockwell Automation Publication MOTION AT005B EN P November 2015 Tuning Method Vertical Axis Tuning Appendix D Use the appropriate procedure described in this section for vertical axis tuning Sercos Drives 1 Set all the Offset values to zero most importantly the Torque Offset General Motion Planner Units Dirve Motor Motor Feedbac
111. re information see Damping Factor on page 14 The loop response settings are described below e A High loop response sets the damping factor z 0 8 which is characterized by a faster rise time with overshoot e A Medium loop response sets the damping factor z 1 0 which is characterized by the fastest possible rise time without overshoot e A Low loop response sets the damping factor z 1 5 which is characterized by a slower response similar to decreasing the bandwidth We recommend a Medium loop response setting Load Coupling Load Coupling refers to whether the mechanical load connected to the motor is rigid or compliant which is described as follows e Rigid systems typically involve high performance load mechanics that are tightly coupled directly to the motor shaft The mechanics are stiff and there is no lost motion e Everything else is compliant including systems with belts and pulleys long shafts short shafts with heavy loads and couplings and gearboxes with backlash and or lost motion Rigid Coupling A loop spacing of 47 is sufficient for rigid loads As a result autotune performs the following control loop gain calculations The damping factor z 1 0 by default Rockwell Automation Publication MOTION AT005B EN P November 2015 53 Chapter 3 54 Autotuning Figure 46 EtherNet IP Drive Autotune Rigid without Load Observer Gain Relationships Default z 1 0 When the load obs
112. rence signal is not too oscillatory or noisy amp Motion Console Axis1 EN NOW X Manual Tuning Reset Motion Generator More Commands I lt System Commands Motion Servo On Z Bandwidth FEM Hertz ve fes 2 0 0 30 0 MSF pg System 1D a Damping MAH z 08 15 Rt MAJ El Tuning Configuration Re MAM VM amp MAS Application Custom a amp MDS Coupling Rigid amp MAFR Gains To Tune Position Integrator Bandwidth Velocity Integrator Bandwidth Using Load Observer with Autotune This procedure applies to Kinetix 5500 Kinetix 5700 and Kinetix 6500 drives It involves configuring the load observer feature after executing an autotune This method also works for any existing set of gains where the Load Ratio is known or manually calculated that is when the Load Ratio gt 0 However we advise that you first try the EtherNet IP drive recommended settings See EtherNet IP Drive Recommended Settings on page 38 for more information 1 Click the Start button on the Autotune tab in the Axis Properties dialog box and perform an autotune Follow all of the steps in Perform Tune on page 2 Click the Load tab in the Axis Properties dialog box and verify that the Load Ratio gt 0 If you manually calculate the Load Inertia Ratio enter the minimum load inertia e If the Measure Inertia using Tune Profile box was checked during autotune the measured Load Ratio is shown in the Load Ratio box e If y
113. ribes the load observer mode settings that can be configured Table 2 Load Observer Configuration Settings IDN P 431 Mode Description Disabled default Load observer is inactive Provides a Torque Estimate only LEE Load Observer with Standard Operation Provides Velocity Estimate Torque and Velocity Estimates Load Observer Only Provides a Velocity Estimate only Velocity Estimate Only Provides Acceleration Feedback by disconnecting the Acceleration Reference to Load Observer Acceleration Feedback This setting is similar to Acceleration Feedback but uses a second input signal Acceleration Reference for increased low frequency disturbance rejection stiffness It corrects error but is fairly aggressive As a result the bandwidth must often be cut in half or significantly reduced It does not provide a Velocity Estimate in place of Velocity Feedback This setting combines the best of the Load Observer Only and Velocity Estimate Only settings Separately velocity estimate provides a smooth response and reduces phase lag but creates error whereas load observer removes error including steady state error in the velocity estimate but it increases phase lag and is fairly aggressive Together they remove error and provide a smooth response With the recommended out of box configuration load observer performs extremely well in situations with changing inertia and unknown levels of compliance and backlash vibration
114. rofiles for Tuning This appendix shows examples of creating move profiles in the Logix Designer application to observe the behavior of an axis while tuning using motion direct commands or JOG MAM or MATC instructions See the Logix5000 Controllers Motion Instruction Reference Manual publication MOTION RM002 for more information on these instructions Depending on the application the move profile can be unidirectional or bidirectional Example 1 An example CAM table is shown that rotates the motor shaft back and forth 1 revolution in 4 seconds Set Pocta ups Tee To T ojoo joo jux amp xu This produces a velocity trapezoid profile with high jerk at the trapezoid corners If the machine mechanics are not robust enough to handle momentary high jerk transients a CAM table is shown that produces smoother motion Rockwell Automation Publication MOTION AT005B EN P November 2015 91 AppendixA Creating Move Profiles for Tuning Example 2 92 The CAM table above is used in an MATC instruction that executes physical motion of the motor Tune Vel Loop ATC Motion Axis Time Cam Axis Axis1 Motion Control MATC 0 Direction 0 Cam Profile TimeCamProfile 0 Distance Scaling Distance 00 Time Scaling Time 00 Execution Mode Once Execution Schedule Immediate Lock Position 0 Lock Direction None Instruction Mode Time Driven Mode Use scaling in the CAM editor to assure the CAM
115. ror Code Extended Enor Code Timed Out Error Path Error T ext Caci ne 2 Ifthe read value is correct skip to Setting Load Observer Gains on page 104 If you want to change the read value do the following a Latch the value b Write the new value to the drive with Sercos IDN P 0 431 Use INT again for the data type Rockwell Automation Publication MOTION AT005B EN P November 2015 103 AppendixC Setting Sercos Gains with IDN Write Messages Message Configuration IDH Write c3 Configuration Communication Tag Message Type SERCOS IDN Write Drive Write Data fi E Bytes New Tag O Enable Enable Waiting Q Stat Q Done Done Length 0 O Error Code Extended Error Code Timed Out e Error Path Error Text c Read the INT value of the load observer configuration with Sercos IDN P 0 431 to verify the change Trigger Vyrite Drive Vurite Data IDM Read DN Drive Read Data 0 Move Source Drive Read Data Dast Drive Write Data D ONE 2 ONS Message Message Control IDN vrie Bil DN Drive VWrite Data Message EN Message Control IDN Verify CON Drive Read Data 0 Drive Configured aa Erect Setting Load Observer Gains Follow a similar procedure to the one previously described to set each of the load observer gains as needed with write and read messages 104 Rockwell Automation Publication MOTION AT005B E
116. rque Low Pass Output Filter is enabled and load observer is not enabled verify that the Torque Low Pass Output Filter Bandwidth Ks x 5 If the Torque Low Pass Output Filter and load observer are enabled verify that the Torque Low Pass Output Filter Bandwidth 2 max K Kop x 5 EtherNet IP Drive Lag Filter EtherNet IP drives provide a lead lag filter with the following first order transfer function Ks 2m F 2nF K als s 2nF s 2nF The filter has a DC gain of 1 a user configurable pole lag at F and a user configurable zero lead at F K User configurable parameters are given below K Torque Lag Filter Gain F Torque Lag Filter Bandwidth in Hz Click the Compliance tab in the Axis Properties dialog box to configure the filter Figure 57 EtherNet IP Drive Lag Filter Parameters General Motor Model Torque Low Pass Filter Bandwidth Imm Hertz Motor Feedback Torque Notch Filter Frequency Hertz Scaling 3 b Hookup Tests Polanty Autotune Load Backlash Compliance E M P Rockwell Automation Publication MOTION AT005B EN P November 2015 75 Chapter5 Filters and Compensation Friction Compensation 76 There are four modes e When K the filter is a low pass filter e When O K 1 the filter is a lag lead The initial use case for the filter was to use it in this mode to compensate for high frequency gain boost associated with compliant load mechanics Wit
117. sabled mode the high frequency limit low frequency limit and tuning threshold are read only and cannot be configured As a result you will have to temporarily enable adaptive tuning to change these settings The adaptive tuning output parameters can be monitored in the Drive Parameters tab of the Axis Properties dialog box Figure 25 Adaptive Tuning Cyclic Reads Drive Parameters to Controller Mapping General H Motor Model Parameters to be read each cycle Parameters to be written each cycle are Name S Name e E Motor Feedback E m LP Value Scaling v TorqueNotchFilterFrequencyEstimate _ PositionTrim 0 0 Hookup Tests v TorqueNotchFilterMagnitudeEstimate E VelocityTrim 0 0 Polarity v TorqueLowPassFitterBandwicthEstimate TorqueTrim 0 0 Autotune AdaptiveTuningGainScalingF actor VelocityFeedtorwardGain Tracking Notch Filter In modes with Tracking Notch Filters the Torque Notch Filter Frequency Estimate is applied to the torque notch filter instead of the Torque Notch Filter Frequency that is visible on the Compliance tab of the Axis Properties dialog box A te Load Adaptive Tuning Adaptive Tuning Configuration Tracking Notch Filter Friction wn Torque Notch Filter High Frequency Limit 2000 0 Hertz Observer Torque Notch Filter Low Frequency Limit 296 33984 Hertz Position Loop Torque Notch Filter Tuning Threshold Bo Motor Rated Velocity Loop Rockwe
118. signal passing through it 73 Chapter 5 74 Filters and Compensation Figure 54 First Order Low pass Filter Bode Plot Cutoff frequency 301 dB P Poss ara Slope 20 dB decade Magnitude dB Stopband Stopband Phase deg 000 001 01 14 0 40 1000 Frequency radisec The signal is attenuated 3 dB at the filter bandwidth also known as the cutoff frequency The low pass filter is first order and has an attenuation of 20 dB decade beyond the cutoff frequency As with any filter its output is shifted in phase from the input If the filter bandwidth is set too low when the filter is enabled the filter s phase lag adds to the stack up of delays around the velocity loop and causes instability This occurs when the filter bandwidth approaches either the velocity loop bandwidth or the load observer bandwidth when load observer is enabled whichever bandwidth is highest In this case the low pass filter must either be disabled its bandwidth increased or the control loop gains decreased For more information on setting the low pass filter see Compensating for High Frequency Resonances on page 69 Sercos Drives For a Sercos drive click the Output tab in the Axis Properties dialog box Check the Enable Low pass Output Filter box and set the Low pass Output Filter Bandwidth to the desired frequency in Hz Figure 55 Sercos Low pass Filter Bandwidth General Motion Planner Units Drive Motor Motor Feedb
119. sition Feedback Figure 18 Load Observer with Velocity Estimate Configuration Value 2 Servo Drive Position Command Control Loops Power Conversion Unloaded Motor Acceleration Reference Torque Estimate Load Observer Figure 19 Velocity Estimate Only Configuration Value 3 Servo Drive Position Command Control Loops Power Conversion Unloaded Motor Torque Estimate Load Observer Torque Load Velocity Estimate Position Feedback Acceleration Reference Velocity Estimate Position Feedback 20 Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Figure 20 Acceleration Feedback Configuration Value 4 Servo Drive Power Conversion Torque Estimate Load Observer Position Command Control Loops Unloaded Motor Acceleration Reference Velocity Estimate Position Feedback Sercos Drive Configuration This section applies to the load observer feature in Kinetix 6000 drives You can configure the load observer feature in a variety of ways by writing to a set of configuration IDN parameters The overall behavior of the load observer is controlled by Load Observer Configuration IDN P 431 This parameter is used to select the load observer mode It can be set to the IDN values listed in Table 2 on page 19 For the remaining IDN descriptions see the following figure Figure 21
120. startilove ons Ji Poston Cfg MovePns z Speed Chg Movespd 20 0 oped Unis Unis per sec MO Tmr Timers O Dd Wirk bis 1 inp RestariMeve ONS Mawe Source Cfg MaovePos 3 Meien Axis Mowe AO Adm T Moien Control ugi Mowe Type 1 Posion C 1g M vaPas2 TT Speed Cfg MoveSpd Doe Speed Unis Unis per sec inp ReverseDrecton Wulbphy source Cig MovePos 2 0 Source B E si r TON Timer On Delay Time Tmr Temera 1 Preset E amp Accum Ea i Ta MovePos 3 UA T l aa Cig Move oF Mi Pe Tewt_Timers 1 DN io Restartove F m ue You can also produce a velocity step with a MAM instruction by entering a very high Accel Rate and Decel Rate However be aware of the following things e Logix Designer application version 19 00 and earlier The default values for Speed Units Accel Units and Decel Units seconds meaning that an Accel Rate 0 seconds is a very high acceleration and produces a velocity step e Logix Designer application version 20 00 and later The default value for Speed Units units second and the default values for Accel Units and Decel Units units second meaning that an Accel Rate 1 000 000 units second is a very high acceleration and produces a velocity step Rockwell Automation Publication MOTION AT005B EN P November 2015 93 AppendixA Creating Move Profiles for Tuning Notes 94 Rockwell Automation
121. t magnitude when disabled Adaptive tuning sets this magnitude estimate equal to the magnitude of the identified 0 100 96 motor rated torque resonance with the highest magnitude In modes with Gain Stabilization adaptive tuning decreases this bandwidth estimate from its default value in 200 Hz increments to l suppress additional resonances above the low n ay W frequency limit if required Additional nds i a resonances are ones that are not already suppressed by notch filters In modes with Gain Stabilization adaptive tuning incrementally decreases this gain scaling factor from its default value to stabilize the system if required The instabilit is caused na un that are not d 0 max float already suppressed by filters or it is caused by filter bandwidths that are too close to the closed loop bandwidth C etheadinti nat de of 0 Disabled ontrols the adaptive tuning feature mode o Pa operation See below for a detailed Disabled Tracking seal Filter description of each mode 2 Gain Stabilization 3 Tracking Notch Filter and Gain Stabilization Resonances are characterized in the following way Torque Low 20 2000 Hz e HF resonances are above the low frequency limit e LF resonances are below the low frequency limit e MF resonances are slightly above the low frequency limit The following sections describe each Adaptive Tuning Configuration mode in detail Disabled Adaptive tuning is alwa
122. th the Automatic value option it can provide a window spanning the minimum and maximum values of the pen across the trend window which is useful when manual tuning to reduce error An example is shown below 91203 8558 AM Taxist ActualVelocity 10 1435 8 190985 a 22501 225 PM a Command Velocity 1 0000 ee PositionError Axis1 VelocityError Em CurrertFeedback fio 000000e 7 10 000000e 7 U UDUUUUE e Display scale checking this box is important when you are fine tuning You can choose how many decimal places to use for values like Velocity Error and Position Error pens shown above In this example 4 decimals are selected and the real value is shown on the trend to 4 decimal places Rockwell Automation Publication MOTION AT005B EN P November 2015 99 AppendixB Creating Trends for Tuning Value Bar Information 100 Sampling Tab The Sampling tab is used to set the sample rate of the pens With tuning you want the sampling rate set as high as possible without affecting the processor speed Because the trend runs as a service in the Logix Designer application you need to consider other online trends and processor utilization A sample period set the same as the Coarse Update Rate of the Motion Group is recommended Name General Display Pens Axis Y Axis Template Sampling Ste S ample Period 1 Milisecond s v Number of Captures Size of Each C
123. ther you manually enter the load ratio or have it calculated during an autotune bump test If you want to manually calculate the load ratio clear the Measure Inertia using Tune Profile checkbox For variable inertia loads perform autotune at the point of lowest mechanical inertia The following table shows the different combinations possible by using the checkboxes in the previous two figures Rockwell Automation Publication MOTION AT005B EN P November 2015 51 Chapter 3 52 Autotuning Table 12 Checkbox Combinations Affecting Load Ratio Calculation Measuring Inertia Use Load using Tune Profile Ratio Result Checkbox Checkbox Bump Test is not performed Only the gains are calculated during autotune based on application type loop response and load coupling Bump Test is performed Total Inertia is measured and calculated but Load Ratio is not calculated Bump Test is not performed The entered Load Ratio is used in other autotune calculations Bump Test is performed Load Ratio is calculated and used in other autotune calculations Gain Calculation The remaining parameters on the Tune tab of the Axis Properties dialog box are used to calculate control loop gains Figure 45 EtherNet IP Drive Autotune Gain Selection Parameters General Tune Control Loop by Measuring Load Characteristics Moto sus Perform Tune Motor Feedback Scaling Hookup Tests Polarity Loop Parameters Tuned Load Customize Gai
124. tial help in getting your product up and running United States or Canada 1 440 646 3434 Outside United States or Canada Use the Worldwide Locator at http www rockwellautomation com rockwellautomation support overview page or contact your local Rockwell Automation representative New Product Satisfaction Return Rockwell Automation tests all of its products to help ensure that they are fully operational when shipped from the manufacturing facility However if your product is not functioning and needs to be returned follow these procedures United States Contact your distributor You must provide a Customer Support case number call the phone number above to obtain one to your distributor to complete the return process Outside United States Please contact your local Rockwell Automation representative for the return procedure Documentation Feedback Your comments will help us serve your documentation needs better If you have any suggestions on how to improve this document complete this form publication RA DU002 available at http www rockwellautomation com literature Rockwell Automation maintains current product environmental information on its website at http www rockwellautomation com rockwellautomation about us sustainability ethics product environmental compliance page Rockwell Otomasyon Ticaret A S Kar Plaza Is Merkezi E Blok Kat 6 34752 erenk y Istanbul Tel 90 216 5698400 www rockwellautomation com
125. tio J Jl Ja Jm R 1 Total system inertia Torque scalar is a function of R which is calculated by the autotune bump test and two parameters K and J which are known by the Logix Designer application and queried from the motion database when a motor is selected Figure 12 Torque Scalar Calculation System Under Control Motor and Motor Load Electrical Mechanics Torque Scalar The torque scalar calculation is triggered when R is updated or a new motor is selected For a Sercos drive the Load Inertia Ratio is located on the Output tab of the Axis Properties dialog box in the Logix Designer application The torque scalar is in the same location labeled Torque Force Scaling Figure 13 Sercos Load Ratio and Torque Scalar General Motion Planner Units Dirve Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset Fault Actions Tag Motot Inertia 0 000044 Kg m 2 Load Inertia Ratio 20 0 Load nina neria Torque Scalar Torque Force Scaling 0 36734396 Rated Position Units s 2 System Acceleration 272 22443 Position Units s 2 at 100 Rated For an EtherNet IP drive the Load Ratio is located on the Load tab of the Axis Properties dialog box in the Logix Designer application The torque scalar is in the same location labeled System Inertia Rockwell Automation Publication MOTION AT005B EN P November 2015 Background Chapter 1 Figure 14 EtherNet
126. tware testing various control loop gain settings to conclude the desired motion can be achieved Compliance and machine vibration can often be minimized by creating a more direct and stiff coupling between the motor and load Helping to achieve this are quality couplings gearboxes actuators and guides If the load requires additional tuning to further optimize motion performance see Manual Tuning on page 61 60 Rockwell Automation Publication MOTION AT005B EN P November 2015 Initialize the Axis Optional Chapter 4 Manual Tuning This chapter describes a generally accepted method of manually tuning a servo drive This method is sometimes referred to as inside out tuning where the inner velocity loop is tuned followed by tuning the outer position loop It involves incrementally increasing control loop gains to the point of marginal stability then backing them off by a given percentage Typical ranges for various gains are also given to provide guidelines The out of box and autotune rigid methods achieve relatively high performance However if you are comfortable with tuning this method can help to further optimize performance from autotune compliant settings or if maximum performance is required This method can be used in the following situations where previously described methods do not produce the required level of performance e To optimize performance starting with out of box or autotuned settings e To tune a dif
127. ue loop bandwidth out of box and during an autotune The position and velocity loop gains are then auto calculated from the Torque Loop Bandwidth 1 Torque Loop Bandwidth Tpw DMIC Hz The Torque Loop Bandwidth displays a default of 1000 Hz under the Torque Current tab in the Axis Properties dialog box of the Logix Designer application It is important to note that this value actually represents the Current Loop Bandwidth and must not be confused with the Torque Loop Bandwidth described here Torque scalar is a torque loop gain that accounts for load inertia It calibrates the control loops so that all gains represent physically measurable bandwidths As a result it scales the system under control to unity gain In other words the motor and load have a gain of one when the torque scalar is applied Figure 11 Scaling Torque in the System System Under Control Motor and Load Mechanics Motor Torque Scalar Electrical Rockwell Automation Publication MOTION AT005B EN P November 2015 15 Chapter 1 16 Background Scaling torque prevents the velocity loop response from being affected by motor gain or load inertia and makes sure that the velocity loop response is represented by the velocity loop bandwidth set by Kp The torque scalar acts as an overall system gain The following definitions are given e K Motor torque constant e J Motor inertia e Jl Load inertia e R Jl J Load inertia ra
128. ult it may be necessary to periodically adjust torque notch filter parameters f Click OK General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaulActions Tag Motor Inertia 0 000044 Kg m 2 Load Inertia Ratio 0 0 Load Inertia Motor Inertia Torque Force Scaling 0 01743257 Rated Position Units s 2 System Acceleration 5716 713 Position Units s 2 at 100 Rated Enable Notch Filter Frequency Notch Filtet Frequency Hertz Enable Low pass Output Filter Rockwell Automation Publication MOTION AT005B EN P November 2015 Notch Filter Filters and Compensation Chapter 5 5 Foran EtherNet IP drive click the Compliance tab in the Axis Properties dialog box and do the following a Set the Torque Notch Filter Frequency to the resonant frequency with the largest magnitude If multiple resonances have nearly the same magnitude set the Torque Notch Filter Frequency to the lowest resonant frequency b If the problem persists set the Torque Notch Filter Frequency to the next highest resonant frequency c If the problem persists set the Torque Low Pass Filter Bandwidth to 2000 Hz and decrement it until ringing stops or until instability occurs If instability occurs detune control loop gains until the system stabilizes d As you change control loop gains or the low pass filter bandwidth resonant frequencies may shift
129. uw eotsbe de cbse baie ode bubo Net so Seen bete dd 33 Gam Calculations sooo edet Nea er ddad ae Senos efss 33 Sercos Drive Recommended Settings cece e ee eee 34 Ether Net IP Drives 25 ner eoo Ee a twodoe see Mako dtes 37 Gun Calculation oo seaies dabo ot debt eei debba ax du edis 37 EtherNet IP Drive Recommended Settings sueuu 38 Is Further Tuning Required oos ligtiaciecaseunnaiGisiansdeed 40 Chapter 3 SOLCOS DIVE chem EUR c M d oss os cane pan Eni aes e DE 43 Bulnip RE E 43 Gan C ACU A OD sie eid arae bei ne eR ehe de S rura bet 44 Using Load Observer with Autotune 0 0c cece eee ee 49 EtheriNct ID DEIVEeS oso soa POS ERANPOILNeRU De x ese cnees 50 PUMP Eestiss von ete ob ardod oben Pale e As Labia eat 50 Can Calcolatore eon blot Ee ERA RN obe a E 52 Using Load Observer with Autotune 0 cece eee eee eee 57 Is Further Tuning Required sonst intiicdeecasechaaniaasiarsdenes 59 Chapter 4 Initialize the Axis Opudiall isis isa ss ox Ree enhedeke aer M EN 61 T nethe Velocity LOO pesscccnacinakaers ended UE RENE RM UI Rd 63 Tunethe Position LOOP caos deb PURO US oun Ta ELE REA 66 Rockwell Automation Publication MOTION AT005B EN P November 2015 3 Table of Contents Filters and Compensation Kinetix 300 Drive Tuning Creating Move Profiles for Tuning Creating Trends for Tuning Chapter 5 Compensating for High Frequency Resonances uueueuus 69 Nocatee e HAMA a eM eR o U
130. ven in the following table Table 4 Load Observer Output Signals m ELE _ 32 bit EE 31 P 0 435 Load Observer Acceleration Estimate Acceleration signed integer 27 1 P 0 436 Load Observer Torque Estimate Torque 16 bit 2 254 UU signed integer When the load observer and the torque low pass filter are both enabled and the low pass filter bandwidth is less than 5 times the load observer bandwidth their interaction can interfere with each other causing instability The low pass filter is always limited to a bandwidth under 389 Hz in drive firmware before revision 1 116 Asa result IDN P 065 was added in drive firmware revision 1 116 to override the torque low pass filter bandwidth limiting The filter is also bypassed if the override IDN P 065 is set to one and the torque low pass filter bandwidth is set to zero This parameter was also added to the Kinetix 7000 drive in firmware revision 1 104 Table 5 Torque Low pass Filter Bandwidth IDN P 0 065 Bandwidth in the Logix Value Designer Application Drive Firmware Notes Operation before revision Limited to lt 389 Hz 1 116 0 0 Filter bypassed Feature added to revision Limited to lt 10 430Hz 1 116 or later See Setting Sercos Gains with IDN Write Messages on page 103 for more information on changing IDN parameter values in the Logix Designer application Connected Components Workbench software can also be used to set IDN parameters For more infor
131. w seconds it analyzes frequency response of torque loop signals to identify track and measure resonances It also analyzes frequency response of command signals to make sure dominant command frequencies are not mistaken for resonances This is known as command rejection The action taken to adaptively change tuning parameters largely depends on the adaptive Rockwell Automation Publication MOTION AT005B EN P November 2015 25 Chapter 1 26 Background Parameter Name Torque Notch Filter Low Frequency Limit Torque Notch Filter High Frequency Limit Torque Notch Filter Tuning Threshold Torque Notch Filter Frequency Estimate Torque Notch Filter Magnitude Estimate Torque Low Pass Filter Bandwidth Estimate Adaptive Tuning Gain Scaling Factor Adaptive Tuning Configuration tuning mode of operation Relevant parameters are summarized in the following table along with detailed descriptions of how they work in various modes of operation Table 8 Adaptive Tuning Attributes Description Default Value Range Units DEM Torque Loop 20 2000 Hz Adaptive tuning identifies resonances not BW associated with command signals between these low and high frequency limits with 2000 20 2000 Hz magnitudes above this tuning threshold 0 100 96 motor rated torque Adaptive tuning sets this frequency estimate Torque Notch equal to the center frequency ofthe identified Filter Freq or O 20 2000 Hz resonance with the highes
132. y UOIYISOd UOILISOd 03U0 UOIlISOd oney yu yeqpse4 pOW 04100 IPOW yeqpse4 wi uonisog JoyesHaquy jeng onea yun xqpJ Peqp end eqpe peo peqpa2a4 1010 oney yun 3poy peqpae pueuluo pJeMJ0Jpa9 DOJA Rockwell Automation Publication MOTION AT005B EN P November 2015 110 Appendix E Block Diagrams Kinetix 6500 Kinetix 5500 and Kinetix 350 drive velocity loop architecture is shown in the following diagram Velocity Loop 3jeumns3 f1po oA J M SqQ peo Kipo sAssapuosusg B e J0p9 6 yeqpse4 Apopa Z peqpa ADOJN KOJA Yeqps9e4 bijuo jaA48sq peo dpow Peqpse4 peqpaaj J03e1623u enq Em Py L peqpesj pegpse enq Cpeqpesj eqpas peo inding yoeqpaay peqpaa4 1070 J03e1623u S2 I0SUaS peqpaa4 ON ADOJN eqpe 4 g4 pop POWPLqp 4 E E Pag ES al pjop 101e1623u 0 peojaid 10 2169 U isnt n 9 amp amp d Jay 4 APOIA JO amp C puewwo 00 y u AyDojan L 1013 ssed m07 apojaA KiDo aA KADON o3u0 uonisog upimpueg Ban LUT popa uut Apora 10 04300 DOJ A ssed M07 9A sog utum apojo MADOA apo 0J1U0 jndino doo UOl ISOd pueululo pueMJOJpo04 UOIneJ9 2252V 111 Rockwell Automation Publication MOTION AT005B EN P November 2015 Block Diagrams Appendix E Torque Current Loop Kinetix 6500 Kinetix 5500 and Kinetix 350 drive torque current loop architecture is shown in the following
133. y Limit 296 33984 Hertz Position Loop Torque Notch Filter Tuning Threshold Bo Motor Rated Velocity Loop b For Kinetix 6500 drives if an audible noise exists at any time while tuning use a smart phone app to identify resonant frequencies and set torque loop filters to remove them See Compensating for High Frequency Resonances on page 69 to tune out resonant frequencies 5 Click the Manual Tune button in the low left corner of the Axis Properties dialog box and adjust the System Bandwidth slider to recalculate the gains with higher or lower values based on the autotune rules and achieve the required level of performance for the application 58 Rockwell Automation Publication MOTION AT005B EN P November 2015 Autotuning Chapter 3 aun jenuejy AJ amp Motion Console Axis1 o mm Manual Tuning Reset Motion Generator More Commands System 26 0 Hert Commands Motion Servo On Bandwidth 0 0 50 0 Nia p is E MAH Damping E 0 8 Fa x E Tuning Configuration Te MAM Application Custom YE Coupling Rigid MAFR Gains To Tune 2 Position Integrator Bandwidth Velocity Integrator Bandwidth 6 Set the Load Observer Bandwidth equal to the Velocity Loop Bandwidth after each adjustment of the System bandwidth slider since the System Bandwidth slider does not affect the Load Observer bandwidth Velocity Loop Loop Bandwidth 77 8 874 Hertz Integrator Bandwidth 0 0 Hertz Integrator Hold Disabled vie Error 3
134. you manually calculate the Load Inertia Ratio enter the minimum load inertia General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset Fault Actions Tag Motor Inertia 0 000044 Kg m 2 Load Inertia Ratio EE Load Inertia Motor Inertia Torque Force Scaling 0 2826076 Rated Position Units s 2 System Acceleration 353 84753 Position Units s 2 at 100 Rated 3 Click the Gains tab in the Axis Properties dialog box Jake note of the Velocity Proportional Gain value You will set the Load Observer Bandwidth IDN P 432 equal to this value in the following step General Motion Planner Units Drive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaultActions Tag Position Gains Proportional IIS SZAKI 1 s Set Custom Gains Integral 5 7756 1 ms s Velocity Gains Feedforward Gains Proportional 383 105 1 s Velocity 100 Integral 00 Vmss Acceleration 9 0 X Integrator Hold Disabled v Rockwell Automation Publication MOTION AT005B EN P November 2015 49 Chapter3 Autotuning Configure these IDN parameter values a IDN P 431 2 b IDN P 432 Velocity Proportional Gain value from the previous step c IDN P 433 0 d IDN P 065 1 File Edit Explore Actions Help ad 59 50959 x e p Devices Node 1 2094D SERVO 0 2094D SERVO Config 0000 1
135. ys running in the background to identify motor side resonances even when the feature is disabled Figure 23 Adaptive Tuning Disabled Load Adaptive Tuning Adaptive Tuning Configuration Disabled icti Torque Noten Filter High Frequency Limit Hertz Friction bserver Torque Notch Filter Low Frequency Limit OR 33984 ne rose 0p Torque Not h Filter Tuning Thre hold ih gt Motor B Velocity Loop Rockwell Automation Publication MOTION AT005B EN P November 2015 Magnilude Motor Rated Background Chapter 1 However no action is taken to compensate for the identified resonances in this mode The result is status only letting you create custom ladder logic to react to changes This is useful for condition monitoring diagnostics and preventative maintenance purposes in tracking HF resonances that change over time To illustrate the idea the following figure shows the frequency response of an identified resonance Note that frequency response graphs like this are not available in the Logix Designer application however adaptive tuning does show the magnitude and frequency estimates Figure 24 Identifying One HF Resonance Torgue Loop Signal Frequency Response Resonance Torque Notch Filter Low Frequency Lari Torque Moich Fiver High Frequency Limit Tongue Notch Fifer Tuning fhreshnok n Torque Netch Fifer Frequency Estimate Torque Notch Fite Magnitude Estimate 10 10 Frequency Hz In Di
136. z Integrator Hold Disabled v Acceleration Feediowand 0 0 et Limits Velocity Limit Positive 1555 5555 Position Urits s Velocity Limit Negative 1666 6666 Position Unites Ero Tolerance 33723668 Position Units s ee N V S a d 62 Rockwell Automation Publication MOTION AT005B EN P November 2015 Tune the Velocity Loop Manual Tuning Chapter 4 For a Sercos drive a value of Ka radians second is a good starting point General Motion Planner Units Dive Motor Motor Feedback Aux Feedback Conversion Homing Hookup Tune Dynamics Gains Output Limits Offset FaulkActions Tag Position Gains Proportional 0 1s Integral 0 0 1 ms s Velocity Gains Feediomward Gains Proportional iE 1 s Velocily 100 by Integral 0 0 1 mss Acceleration 0 0 x Follow these steps to manually tune the velocity loop 1 Create a move profile in the Logix Designer application to observe the behavior of the mechanical load while tuning See Appendix A for more information on Creating Move Profiles for Tuning An example CAM table for an MATC instruction is shown below Mira 2 Create a trend in the Logix Designer application to monitor Command Position Command Velocity Torque Reference Position Error and Velocity Error See Appendix B for more information on how to Create Trends for Tuning The following is an example trend Rockwell Automation Publication MOTION AT005B EN

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