Switching amplifier for piezoelectric actuators
Contents
1. Properties Standard technical 25 Unit Nominal values SA75A conditions values values Notes Preliminary data Fon uc AlE Max number of channels 2 Thermal Protection Current limitation Voltage limitation Main voltage VDC 0 240 Output voltage V 20 150 Min Output voltage V 20 21 0 19 0 Max Output voltage V 150 147 0 153 0 Voltage Gain VV 20 19 4 20 6 Peak current limitation mA 5000 00 4500 0 5500 0 Peak output power Sine output VA 320 00 275 5 351 9 Output load capacitance 400 480 Control input voltage V 1 7 5 Min input voltage V 1 1 10 1 00 Max input voltage V 759 7 50 7 88 Ripple current 0 08 Total Harmonic distorsion 2 2 00 4 00 Signal Noise ratio 70 00 63 TE Loaded output bandwidth With 72uF calibrated load Hz 130 03 Unloaded output bandwidth With 1 55uF calibrated load Hz 1000 00 800 1100 DC offset setting 10 turns potentiometer Min DC offset V 1 00 1 02 0 98 Max DC offset V 7 50 G30 7 65 PZT connector LEMO 2 302 External Sensor connector External Control Input BNC type Input impedance kQ 10 00 Back panel interface n 2 Weight kg Dimengons W L H Compatible with rack 84F 4H mm x mm x mm 12F wide 3H high Cooling Forced air Min Max ambiant Temperature C 0 40 Option Actuator temp sensor LEMO EPG 00 302 NLN 1 Tn all CEDRA2. Servo controller CEDRAT TECHNOLOGIES 34 Version 1 0 0 11 04 14 SA75 Product and Warranty information ANNEX 6 TROUBLE SHOOTING FORM In case of trouble or breakdown with the electronic device this form must be completed by the customer in order to Allow Cedrat Technologies to authorise the product return back to the factory Help Cedrat Technologies in repairing it Product Please give mention here the references and delivery date History Please summarise here every action which has been performed with the device since the delivery Problem description Please describe here the problems faced with the electronics and which are not described in the paragraph 7 Notations Please define here the short term used for external devices plugged in the electronics in order to make the writing of problem identification easier Problem identification Please summarise and describe here using the notations the operation that could lead to problem identification Action Please mention and update here every action undertaken by yourself by Cedrat Technologies or by your local vendor Please note that you need to get the authorisation from CEDRAT TECHNOLOGIES before sending back the hardware CEDRAT TECHNOLOGIES 35 Version 1 0 0 11 04 14
3. 5 LEMO connector for piezo actuator channel 1 B6 LEMO connector for over temperature protection of piezo actuator channel 1 CEDRAT TECHNOLOGIES 6 Version 1 0 0 11 04 14 SA75 Product and Warranty information Nota If overvoltage overtemp or overcurrent appear on the SC75 board side the 6 lights red but no flag appears on 1 2 WARNING A special care in the use of the LEMO connections should be taken in plugging and unplugging them you have to pull onto the connector and not the cable It is strictly forbidden to connect the electrical output channels of several SA75x in parallel The switching amplifier should be connected to a piezo load before switch on the A7 switch Power on If not the power amplifier could be unstable This product contains components with lethal voltage it is strictly forbidden for the user to remove the boards from the rack In the same way it is strictly forbidden to disconnect the load when electrically powered CEDRAT TECHNOLOGIES 7 Version 1 0 0 11 04 14 SA75 Product and Warranty information 2 GENERAL DESCRIPTION The switching electronic SA75X is dedicated to the supply and control of piezoelectric actuators based on multi layers piezoelectric ceramics such as APA or PPA from CEDRAT TECHNOLOGIES The SA75X consists in a power supply with a maximal power given in the attached technical data sheet including see Figure 2 A switching power supply SC75 providing a co
4. dB 70 00 63 77 Loaded output bandwidth With 72uF calibrated load Hz 520 11 Unloaded output bandwidth With 1 55uF calibrated load Hz 1000 00 800 1100 DC offset setting 10 turns potentiometer Min DC offset V 1 00 1 02 0 98 Max DC offset V 7 50 7 35 7 65 PZT connector LEMO EGH 2B 302 CC External Sensor connector External Control Input BNC type Input impedance kQ 10 00 Back panel interface Marin T P jr 8 n Weight kg Dime sons W L H Compatible with rack 84F 4H T mm x mm x mm 12F wide 3H high Cooling Forced air Min Max ambiant Temperature ne 0 40 Option s Actuator temp sensor 2 LEMO EPG 00 302 NLN CEDRAT TECHNOLOGIES 33 Version 1 0 0 11 04 14 SA75 Product and Warranty information Properties standard technical conditions of use and measurement Quasistatic excitation AC voltage between 20 and 150 V at 1 Hz Environment Ambient temperature 15 25 C and dry air Humidity 50 rH Standard main supply Main according to directive HD472 could be adapted to 110 VAC on request Noise measurement Excitation 0 5 Vrms reading bandwidth 1 Hz to 1 kHz conditions Standard load Actuator APA from series S or SM 1 55 pF load test may be different Any technical conditions of use different from those defined above can lead to temporary or definitive alterations of properties Thank you to contact CEDRAT TECHNOLOGIES before u
5. offset V 1 00 1 02 0 98 Max DC offset V 7 90 1535 7 65 PZT connector LEMO EGH 2B 302 CC External Sensor connector External Control Input BNC type Input impedance kQ 10 00 Back panel interface D 2 us igs 2 5 E Weight kg Dimensions W L H Compatible with rack 84F 4H mm x mm x mm 12F wide 3H high Cooling Forced air Min Max ambiant Temperature C 0 40 opion CEDRAT TECHNOLOGIES 31 Version 1 0 0 11 04 14 SA75 Product and Warranty information Bandwidth settled according to your specifications Properties standard technical conditions of use and measurement Quasistatic excitation AC voltage between 20 and 150 V at 1 Hz Environment Ambient temperature 15 25 C and dry air Humidity 5O rH Standard main supply Main according to directive HD472 could be adapted to 110 VAC on request Noise measurement Excitation 0 5 Vrms reading bandwidth 1 Hz to 1 kHz conditions Standard load Actuator APA from series 5 or SM 1 55 pF load test may be different Any technical conditions of use different from those defined above can lead to temporary or definitive alterations of properties Thank you to contact CEDRAT TECHNOLOGIES before using actuators under non standard technical conditions Factory tests carried out 4 Test 1 Load and discharge time 04 Test 2 Linearity output voltage vs input voltage Extra factory tests C Test 3 Gain and linearity in c
6. on the H Bridge and the amplifier switches 5 Apply through B2 BNC connector the order We suggest before sending the final command to valid the voltage output by applying small signals This suggestion limits some risks on the piezo actuator with a bad order 6 To switch off the output voltage of the switching amplifier the operator may only suppress it command or applying OV 7 If maintenance on the piezo actuator or its harness is necessary the operator should switch off the 7 switch to avoid electrical risk Nota A specific sequence is applied on the switching amplifier when the operator switches on the A7 switch Accordingly when the SC75 is powered on the SA75 waits few hundred milliseconds to be operational and able to send the command on the amplifier See Figure 7 This sequence is necessary to well start the switching amplifier If the sequence doesn t work well the A6 led will light red In this case the operator re initialises the process by switching off the A7 switch followed by switching on SC75 timing OFF ON SA75 timing OFF ON ORDER ENABLE Order timing SC75 start SA75 start 4 1 4 Figure 7 Automatic Ttming during ON switching WARNING When the switching amplifier is commanded to supply the piezo with large current the operator should valid that the small rise and fall time don t excite the mechanical resonant frequency of the piezo mechanism If no protec
7. replacement of the external fuse s For any other matter or breakdown suspicion we suggest the customer to contact your local vendor 10 WARRANTY CONDITIONS AND EXCEPTIONS The equipment is warranted for one year including parts and labour and only under standard technical conditions as outlined above and expressly mentioned in the technical data sheet Repairs will be carried out at CEDRAT TECHNOLOGIES or through your vendor Shipping handling and insurance costs to return a part for repair must be paid by the customer Interventions or attempts to service or repair the SA75 by any unauthorised persons will invalidate this warranty 11 INSPECTION UPON RECEIPT This product has been inspected and shown to operate correctly at the time of shipment as verified by the Factory Verification Form that accompanies the power supply Immediately upon receipt of the product it should be inspected carefully for any signs of damage that may have occurred during shipment If any damage is found a claim should be filed with the carrier The package should also be inspected for completeness according to the enclosed packing list If an order is incorrect or incomplete contact your distributor CEDRAT TECHNOLOGIES 25 Version 1 0 0 11 04 14 SA75 Product and Warranty information CEDRAT TECHNOLOGIES recommends the customer to keep the original package for any further carriage of the electronic product 12 AFTER SALES SERVICE If a
8. to drive reactive load With specific topology the energy stored in the capacitive load can be transferred in the SC75 power supply In this case the switching amplifier doesn t consume the reactive power but only the active power of the piezoactuators plus the losses in the power switching functions Ex A switching power amplifier providing sine signal 10amps at 170ppk to the load ie 625VA consumes less than 12 5W from piezo dielectric losses plus 30W due to the power components losses CEDRAT TECHNOLOGIES 12 Version 1 0 0 11 04 14 SA75 Product and Warranty information 3 MAIN VOLTAGE CONNEXIONS The switching amplifier is able to be connected on the 110VAC or 230VAC main voltage with any modifications 3 1 Fuses SC75 110Vac SC75 230Vac fuse 1 250V 2A T type fuse 1 250V 2A T type fuse 2 250V 2A T type fuse 2 250V 2A T type Nota The fuse are reachable in the main voltage plug on the rear face CEDRAT TECHNOLOGIES 13 Version 1 0 0 11 04 14 SA75 Product and Warranty information 4 OPERATING INSTRUCTION FOR THE SWITCHING POWER SUPPLY AC DC CONVERTER SC75 This module produces from the mains the regulated DC voltage to the amplifier functioning needs 200Vdc regulated voltage with 150W max output power The switch A7 is used to power on and off the power supply and the amplifier There is a delay of less than two seconds between the activation of the switch and the effective start up of
9. OF CONTENTS 1 5 SYNOPTIC n dee Aces NE MEE EI Ome 5 3 GENERAL 5 8 4 VOLTAGE 5 13 USSR ots eod Dac a iet meer ENE ee 13 5 OPERATING INSTRUCTION FOR THE SWITCHING POWER SUPPLY AC DC CONVERTER 5 75 14 6 OPERATING INSTRUCTION FOR THE AMPLIFIER SA75X 15 6 1 General IST PUCTIORS ate clade 15 6 2 Voltage control and current limitation 18 6 3 Open closed e ettam amine iem 18 6 4 Using the push pull mode 2 channels only for SA75X 2 18 7 OPERATING INSTRUCTIONS FOR THE OPTIONAL 5675 STRAIN GAUGES 20 7 1 General instructions TL eb enn 20 48 Thermal EF Tot uen Debent etri 20 8 OPERATING INSTRUCTIONS FOR THE OPTIONAL ECS75 EDDY CURRENT SENSOR 21 8 1 General instructions etico bre e 21 8 2 Eddy current displacement 21 9 OPERATING INSTRUCTIONS FOR THE OPTIONAL UC45 DIGITAL CONTROLLER 22 9
10. T SENTROGUCTION need nel 22 9 2 Terms and definitions eco e edu 22 9 3 SYNOPTIC NR 23 10 TROUBLE SHOOTING 2 ieee alos 24 11 WARRANTY CONDITIONS AND EXCEPTIONS 25 12 INSPECTION UPON RECEIPT odit 25 I3 AFTER SALES SERVICE ionic hires tee due ota ries etta euh 26 ANNEX 1 5 27 CEDRAT TECHNOLOGIES 3 Version 1 0 0 11 04 14 SA75 Product and Warranty information Scheme of the cable connection for standard electrical configuration 27 ANNEX 2 EFFECT OF THE CURRENT LIMITATION 28 ANNEX 3 SA75A X TECHNICAL DATA SHEET 29 ANNEX 4 SA75B X TECHNICAL DATA SHEET 31 ANNEX 5 SA75D TECHNICAL DATA 33 ANNEX 6 TROUBLE SHOOTING 35 CEDRAT TECHNOLOGIES 4 Version 1 0 0 11 04 14 SA75 Product and Warranty information 1 SYNOPTIC The switching amplifier SA75 multi channel consists 19 inches casing to the following dimensions Rack 84F 4U Width 470 mm Length 310 mm Height 200 mm This electronic is a modular one which means that a rack84F for instance may receive two power supply units SC75 and up to 4 amplification channels SA75X_Y X represen
11. T TECHNOLOGIES SA documents the decimal sign is a comma on the line ISO 31 0 1992 CEDRAT TECHNOLOGIES 29 Version 1 0 0 11 04 14 SA75 Product and Warranty information Bandwidth settled according to your specifications by default 1 Hz Properties standard technical conditions of use and measurement Quasistatic excitation AC voltage between 20 and 150 V at 1 Hz Environment Ambient temperature 15 25 C and dry air Humidity 50 rH Standard main supply Main according to directive HD472 could be adapted to 110 VAC on request Noise measurement Excitation 0 5 Vrms reading bandwidth 1 Hz to 1 kHz conditions Standard load Actuator APA from series S or SM 1 55 load test may be different Any technical conditions of use different from those defined above can lead to temporary or definitive alterations of properties Thank you to contact CEDRAT TECHNOLOGIES before using actuators under non standard technical conditions Factory tests carried out X Test 1 Load and discharge time X Test 2 Linearity output voltage vs input voltage Extra factory tests L Test 3 Gain and linearity in closed loop LI Test 4 Step response in closed loop sensor output voltage versus command voltage L Test 5 Thermal test at full load Available options UC Servo controller CEDRAT TECHNOLOGIES 30 Version 1 0 0 11 04 14 ANNEX 4 SA75B X TECHNICAL DATA SHEET Table of standard properties of use and me
12. W CEDRAT TECHNOLOGIES Innovation in Mechatronics SA75 Switching Amplifier for Piezoelectric Actuators PRODUCT AND WARRANTY INFORMATION Version 1 0 0 Date 11 04 14 CEDRAT TECHNOLOGIES SA URL http www cedrat technologies com 59 Chemin du Vieux Ch ne Inovall e Email actuator cedrat tec com F 38246 MEYLAN CEDEX Phone 33 0 4 56 58 04 00 FRANCE Fax 33 0 4 56 58 04 01 SA75 Product and Warranty information CAUTION READ BEFORE OPENING For safety purposes these instructions must be read before use of this product This power amplifier is dedicated to multilayers piezoelectric actuators Only qualified personnel should work on or around this equipment and only after becoming thoroughly familiar with all warnings safety notices and procedures contained herein The successful and safe operation of this equipment is dependent on proper handling installation and operation A qualified person is one who is familiar with the installation construction and operation of the equipment and the hazards involved In addition he she has the following qualifications e is trained and authorized to energize de energize clean and ground equipment in accordance with established practices e is trained in the proper care and use of protective equipment in accordance with established safety practices CEDRAT TECHNOLOGIES 2 Version 1 0 0 11 04 14 SA75 Product and Warranty information TABLE
13. asurement The properties defined in the table below are set up according to the technical conditions of use and measurement These properties are warranted within their variation range and in compliance with the standard technical conditions of use Bandwidth settled according to your specifications by default 1 Hz SA75 Product and Warranty information Properties Standard technical Min Max a Unit Nominal values SA75B conditions values values Notes Preliminary data Fon uc alll Max number of channels 2 Thermal Protection Current limitation Voltage limitation Main voltage VDC 0 240 Output voltage V 20 150 Min Output voltage V 20 21 0 19 0 Max Output voltage V 150 147 0 153 0 Voltage Gain VV 20 19 4 20 6 Peak current limitation mA 10000 00 9000 0 11000 0 Peak output power Sine output VA 630 00 551 0 703 8 Output load capacitance 400 480 Control input voltage V Min input voltage V 1 1 10 1 00 Max input voltage V 7 5 7 50 7 88 Ripple current 0 08 Total Harmonic distorsion 2 2 00 4 00 Signal Noise ratio 70 00 63 77 Loaded output bandwidth With 72uF calibrated load Hz 260 06 Unloaded output bandwidth With 1 55uF calibrated load Hz 1000 00 800 1100 DC offset setting 10 turns potentiometer Min DC
14. conditioner Although the probe is calibrated with the target the gain is somewhat dependent on the angle between the probe and the target the target s thickness CEDRAT TECHNOLOGIES 21 Version 1 0 0 11 04 14 SA75 Product and Warranty information OPERATING INSTRUCTIONS FOR THE OPTIONAL UC45 DIGITAL CONTROLLER OPTION 8 1 Introduction This mezzanine optional board UC45 is stackable on the amplifier board and allows the support of two channels Only one controller is available on the UC45 board except in the case of the control of stage with Eddy Current Sensors Only the input and output channel selection is configurable on a single board Two boards with appropriate input output selection are necessary for a two channel application The optional board UC45 is available for the boards SA75A x SA75B x and SA75D x It performs digital closed loop control with a PID and output filter configuration The output filter can be either of type notch or lowpass The optional board UC45 is delivered with a free standard version latest version downloadable on the web site of a Graphical User Interface GUI software HPDM45 This GUI is a Labview executable software the Labview from National Instruments is not transferred and provides the following functionalities Remote control of the drive electronic Change of the parameters of the controller PID and filter Order selection between internal e g generated by the GUI e
15. device requires service please contact CEDRAT TECHNOLOGIES or your local vendor Please include the device model and serial number all correspondence with CEDRAT TECHNOLOGIES or your vendor CEDRAT TECHNOLOGIES 26 Version 1 0 0 11 04 14 SA75 Product and Warranty information ANNEX 1 CONNECTIONS Scheme of the cable connection for standard electrical configuration Driving Coaxial LEMO electronics Banana plugs 4mm male Banana plugs 4mm female m connection Floating Floating 2 Amolifi Piezo Actuator Electrical cable 1 50 m for standard connection mon Earth Note the piezo connexions are floatting Only mechancical shell could be connected to earth CEDRAT TECHNOLOGIES 27 Version 1 0 0 11 04 14 SA75 Product and Warranty information ANNEX 2 EFFECT OF THE CURRENT LIMITATION With a switching amplifier the applied voltage to the actuator is directly proportional to the input signal The gain of the power amplifier SA75x is set to 20 So to obtain the whole stroke of a given actuator one should input a signal varying from 1V to 7 5V The applied voltage on the actuator will then vary from 20 to 150V There is some limitation to the constant gain of the amplifier Indeed when the variation speed of the input signal order increases the current limitation of the amplifier limits the slew rate of the output voltage The current provided to a piezo ceramic is depending on its capacitance and on the varia
16. fault the output of the SA75X is switched OFF and only an OFF ON sequence on A7 switch could rearm the protection to re initialise the latch 5 3 Open closed loop By default the open closed loop selector should be set on the mode open loop SERVO OFF in that mode the amplifier applies a voltage gain of 20 to the input A displacement sensor its conditioner and a servo controller will be necessary to use the closed loop SERVO ON otherwise the order will be set to zero 5 4 Using the push pull mode 2 channels only for SA75X 2 For some piezoelectric devices such as the piezoelectric tilts or XY stages it is necessary to supply two actuators simultaneously A zero positioning is achieved with an electrical centring Such a configuration could easily be achieved by using two channels of the SA75 according to the figure shown below CEDRAT TECHNOLOGIES 18 Version 1 0 0 11 04 14 SA75 Product and Warranty information Piezo actuator 1 OHO wie T Piezo actuator 2 Voltage amplifier Figure 8 Possible connection for driving piezo actuator in push pull mode WARNING Do not unplug the SA75 boards when the rack is powered on This causes large electrical damage and risk for the operator CEDRAT TECHNOLOGIES 19 Version 1 0 0 11 04 14 SA75 Product and Warranty information 6 OPERATING INSTRUCTIONS FOR THE OPTIONAL 5675 STRAIN GAUGES CONDITIONER 6 1 General instructions Th
17. ge is limited like a slew rate see Figure 5 Voltage gain versus frequency 180 160 140 120 100 50 uF 100 UF 80 200 pF Vo V peak to peak 60 40 20 100 1000 Frequency Hz Figure 4 Power bandwidth description for different loads The second one is the possibility to drive a piezo when the power bandwidth is not reached small signal This parameter is directly linked to the voltage controller performance see Figure 5 CEDRAT TECHNOLOGIES 10 Version 1 0 0 11 04 14 SA75 Product and Warranty information Gain f with 29 4 27 4 25 4 23 4 Gain f Gain dB 10 100 1000 10000 Frequency Hz Phase f with 30uF Phase f Phase 9 100 120 140 10 100 1000 10000 Frequency Hz Figure 5 Signal bandwidth description for a load CEDRAT TECHNOLOGIES 11 Version 1 0 0 11 04 14 SA75 Product and Warranty information Voltage limitation An onboard input voltage limitation is implemented to avoid some voltage limitations on the piezo load This limitation doesn t protect the piezo when over ringing appears on the output voltage voltage control behavior Energy recovery on board The switching amplifier is well suited
18. hstand more than 250V should be used If the operator doesn t take this precaution damage on the switching amplifier may arise In the next lines main performances are explained Voltage control loop on board A specific controller is implemented to control the output voltage on the piezoactuators The controller is tuned with the output load to provide the best performances in regards of the control speed and accuracy For the reason your switching amplifier is tuned with factory settles and the operator cannot change the load without lack of these performances A range around the initial value is specified corresponding to 25 100 Ex The switching piezo amplifier is tuned with initial piezo is 30uF the switching amplifier is stable on the range 20 60 Bandwidth and current limitation The power switching amplifier is characterized with two specific limitations The power bandwidth signal bandwidth The first one is due to the possibility to the SA75X to provide the necessary current to charge and discharge the piezo load a capacitance This is the current or power capability Following the next formulae T C dV on dt The max current is function of your switching power amplifier current range 5 10 or 20amps If the commanded signal is high frequency and when the max CEDRAT TECHNOLOGIES 9 Version 1 0 0 11 04 14 SA75 Product and Warranty information output current is reached the output volta
19. is module allows reading up to three strain gauges bridges For each one of them you can e Read the signal emitted by the conditioner C2 e Adjust the offset C3 The gain and the offset of the conditioner are adjusted at the factory ona gauge bridge set on the piezoelectric actuator but only the offset is accessible to the user C3 If you wish to use the conditioner with another actuator it may be necessary to modify the gain at the factory 6 2 Thermal effect The strain gauges solution is the easiest way to operate a piezoelectric actuator in a closed loop The best accuracy that can be achieved with this sensor is around 0 025 However the strain gauges sensor is temperature dependent so that the offset may vary with temperature CEDRAT TECHNOLOGIES 20 Version 1 0 0 11 04 14 SA75 Product and Warranty information 7 OPERATING INSTRUCTIONS FOR THE OPTIONAL ECS75 EDDY CURRENT SENSOR CONDITIONER 7 1 General instructions The ECS75 card includes up to 2 channels of Eddy Current sensors which have been calibrated at the factory Only the offset can externally corrected F2 F5 trimmers Figure 9 Front panel of the ECS75 2 board 7 2 Eddy current displacement sensors The Eddy Current displacement sensor is a non contact proximity sensor using the eddy current effect generated by the probe in a preferably nonferrous material target The eddy current changes the impedance of the probe which is read by the
20. losed loop Test 4 Step response in closed loop sensor output voltage versus command voltage L Test 5 Thermal test at full load Available options x SC Servo controller CEDRAT TECHNOLOGIES 32 Version 1 0 0 11 04 14 SA75 Product and Warranty information ANNEX 5 SA75D TECHNICAL DATA SHEET The properties defined in the table below are set up according to the technical conditions of use and measurement These properties are warranted within their variation range and in compliance with the standard technical conditions of use Bandwidth settled according to your specifications by default 1 Hz Properties Standard technical SA75D conditions Mnt Nominal values values values Notes Preliminary data Fun pss Max number of channels 1 Thermal Protection Current limitation Voltage limitation Main voltage VDC 0 240 Output voltage V 20 150 Min Output voltage V 20 21 0 19 0 Max Output voltage V 150 147 0 153 0 Voltage Gain VV 20 19 4 20 6 Peak current limitation mA 20000 00 18000 0 22000 0 Peak output power Sine output VA 1370 00 1102 0 1407 6 Output load capacitance HF 400 480 Control input voltage V Min input voltage V 1 1 10 1 00 Max input voltage V Yes 7 50 7 88 Ripple current 8 Total Harmonic distorsion 2 2 00 4 00 Signal Noise ratio
21. ntinuous voltage from the main power 15 module e A switching power amplifier SA75X dedicated to capacitive load allowing excitation of piezoelectric actuators between 20 and 150 V 274 module A strain gauge conditioner 5675 allowing to measure the displacement of piezoelectric actuators equipped with gauges optional module A servo controller UC45 allowing to close the loop and to insure a feedback control on the actuator optional module Open Close Loop hr ES Input Saturation Signal Power Current Amplifier Limiter Controller Gauge Sensor 5 0 Gauge Sensor Figure 2 Synoptic of the electronic control of a piezo actuator A switching amplifier is built around PWM technics and a dedicated output filter including inductors and the piezo load As the piezo load is capacitive the output PWM is filtered and a continuous output signal is supplied to the piezo load see Figure 5 CEDRAT TECHNOLOGIES 8 Version 1 0 0 11 04 14 SA75 Product and Warranty information SA7SD Filter 5 c1 2 HE d nso 3 e TA ad elc al a ME ho Bn Bh 5 Ns er aye ae Controller Feedbacks Figure 3 Synoptic of a switching piezoelectric amplifier WARNING The output piezo connexions are floating This means if the operator wants to measure the output voltage on the load a differential probe able to wit
22. oaxial LEMO connector in one end and 2 banana 4mm plugs in second end see Annex 1 A thermal protection of the piezo is implemented when 6 is connected with the temperature sensor embedded on the piezo actuator When the surface temperature reaches 80 C the output of the SA75X is switched OFF and only an OFF ON sequence on 7 switch could rearm the protection to re initialise the latch The operator should follow the next sequence to assure a proper use of the switching amplifier 1 Connect the piezo load on the switching amplifier output If the load is not connected the voltage output could be unstable For piezoactuators with metallic shell the operator could connect the shell to the earth 2 Switch on the main selector on the rear panel The A2 A3 A4 blinks red during few milliseconds and the A6 led should light green If not don t follow the sequence and call your vendor 3 Verify that B4 is in correct position Servo Off if the piezo is not coupled with position control loop or Servo On if the piezo is coupled with CEDRAT TECHNOLOGIES 15 Version 1 0 0 11 04 14 SA75 Product and Warranty information position control loop If servo is in On position with no position control loop a DC signal will be apply on the command corresponding to 5V output 4 The operator should switch on the A7 switch to power on the switching amplifier with no order through B2 BNC zero command With this operation the Bus voltage is applied
23. oix ordre 572 0 Notch_num z Notch_num z a Filtre ADC1 1 Notch den z Notch den z Filtre DAC Notch 1 Notch 2 1 K Ts C1 238 pl Pl Order Tau_ADC s 1 fh x z1 po L th i owp ass Tau_DACs 1 command ADC order Filter num z Choix filtre DAC 4 Filter den z ike pe Sum Tau_ADC st4 Ken sz Choix filtre Filtre ADC2 sensor Figure 10 Synoptic of the UC45 controller CEDRAT TECHNOLOGIES 23 Version 1 0 0 11 04 14 SA75 Product and Warranty information 9 TROUBLE SHOOTING PROBLEMS THE PLUGGED PIEZO ACTUATOR DOES NOT MOVE WHILE THE REAR CONNECTION AND THE 7 ARE SWITCHED ACTION POSSIBLE CAUSES Check the led 6 a If A6 is off check the main cable and the fuses at the misconnection with main cable or burnt rear panel fuses b If A6 is red The electronics is in protection check the connection lines to the piezo May be a short circuit through the cable actuator disconnect every LEMO cable connection or through the piezo actuator Test the electronics with the unplugged and occurred plugged piezo actuator as follows Switch A7 off If A6 is green Switch A7 on if the electronics works an external parasitic noise might have disturbed it if the electronics doesn t work a breakdown is certain If A6 is red Wait for 10 minutes and switch A7 on if the electronics works The electr
24. onics was in thermal protection and needed to cool itself down if the electronics doesn t work a breakdown is certain PROBLEMS INCOHERENT RESPONSE FROM THE ACTUATOR IN OPEN LOOP ACTION POSSIBLE CAUSES Check the output signal B5 the DC offset may be wrong If the DC offset is wrong turn B3 to settle it PROBLEMS INCOHERENT RESPONSE FROM THE ACTUATOR IN CLOSED LOOP ACTION POSSIBLE CAUSES Go back in mode SERVO OFF B4 and check the the strain gauges offset C3 may be wrong sensor s response C2 10 turns potentiometers are used do not hesitate to rotate the potentiometers and keep attention to the clic noise arising at the end of the trimmer range CEDRAT TECHNOLOGIES 24 Version 1 0 0 11 04 14 SA75 Product and Warranty information Adjusting the Strain Gauge offset Apply a command of OV by a 50 Ohms BNC connector on B2 for instance Check that the voltage output on 5 is nearly zero Adjust the potentiometer B3 to get the output B5 near zero Measure the output of the Strain Gauge conditioner C2 Adjust the potentiometer C3 so that the output C2 is 0 38 V One has SetPointLA 1 MaxAmplitudeLA MaxAmplitudeSG 0 5 With MaxAmplitudeLA 8 5 MaxAmplitudeSG 7 5 The customer is not entitled to modify the power supply or the switching amplifier The only manipulations allowed to him are described in the set here above including the
25. sing actuators under non standard technical conditions Factory tests carried out X Test 1 Load and discharge time X Test 2 Linearity output voltage vs input voltage Extra factory tests L Test 3 Gain and linearity in closed loop Test 4 Step response in closed loop sensor output voltage versus command voltage DT Test 5 Thermal test at full load Available options x UC Servo controller Properties standard technical conditions of use and measurement Quasistatic excitation AC voltage between 20 and 150 V at 1 Hz Environment Ambient temperature 15 25 and dry air Humidity lt 50 rH Standard main supply Main according to directive HD472 could be adapted 110 VAC on request Noise measurement Excitation 0 5 Vrms reading bandwidth 1 Hz to 1 kHz conditions Standard load Actuator APA from series 5 or SM 1 55 uF load test may be different Any technical conditions of use different from those defined above can lead to temporary or definitive alterations of properties Thank you to contact CEDRAT TECHNOLOGIES before using actuators under non standard technical conditions Factory tests carried out 4 Test 1 Load and discharge time 04 Test 2 Linearity output voltage vs input voltage Extra factory tests Test 3 Gain and linearity in closed loop CI Test 4 Step response in closed loop sensor output voltage versus command voltage Test 5 Bode diagram Available options 04 UC
26. the SC75 SA75 It is possible to neutralise supplied power voltages by using the switch A7 This Switch is the easiest way to disable the piezoelectric actuator as soon as required However few seconds are necessary to come to a completely discharged actuator This module is protected against over temperature over voltage and over current conditions WARNING It is recommended to keep free space all around the electronic rack while driving in order to make the ventilation easier and to obtain the nominal performance of the driving electronics Note Do use the tilt feet for the SA75 rack versions Do not unplug the SC75 boards when the rack is powered on This causes large electrical damage and risk for the operator CEDRAT TECHNOLOGIES 14 Version 1 0 0 11 04 14 SA75 Product and Warranty information 5 OPERATING INSTRUCTION FOR THE AMPLIFIER SA75X 5 1 General instructions The switching amplifier allows applying to the actuator a signal comparable to the order s one with a gain of 20 see Figure 6 offset Piezo Actuator Input signal order Voltage amplifier Figure 6 Principle of switching voltage amplifier The order may be applied in two different and complementary manners Static offset potentiometer screw e Dynamic order B2 connectors These two signals are added and their sum should fall between 1V and 7 5V To connect the actuator to the voltage amplifier the standard cable available is a c
27. tion is taken into account damages on the MLA can occur with electric and mechanical damages on each part CEDRAT TECHNOLOGIES 16 Version 1 0 0 11 04 14 SA75 Product and Warranty information If the operator wants to increase the length of the harness the wire section should be above 1 5mm to be compatible with the large current flow CEDRAT TECHNOLOGIES 17 Version 1 0 0 11 04 14 SA75 Product and Warranty information 5 2 Voltage control and current limitation If the order signal is below 1 V or above 7 5 V a protective diode and the power amplifier saturation will clamp the signal so that the voltage applied to the actuator stays roughly between 20 V and 150 V There are some limitations to the constant gain of the amplifier Indeed when the variation speed of the input signal order increases the current limitation of the amplifier limits the slew rate of the output voltage This current limitation varies with the power amplifier SA75X version see annex 3 Nota the use of a digital input signal B2 may generate parasitic noise so that an additional filter may be necessary Over current and over voltage protections are implemented e One over current protection on the output current to avoid damage if large currents are demanded e One over current protection on the H bridge if cross conduction appears e Over voltage protection on the output voltage to avoid damage if large voltage are demanded For each de
28. tion speed of the applied voltage including internal controller response The current for a capacitive load is given by the following expression dv piezo piezo dt For a given current limitation the shortest load time is given by AV xC piezo Load lim given by The max frequency for a triangle signal is d ensi max 2xAVxC piezo If we consider a sine signal then the maximal frequency is given by f sin max _ 2x ly AV xC x 20 piezo Tek 250KS s m 117 Acqs Input Signal 50 0 M2 00ms 4 7 5 00 V A 175V 21V C4 Freq 5 0 13 Feb 2003 19 44 27 Figure A 1 The current limitation limits the voltage slew rate of the piezo Type of switching amplifier SA75A SA75B SA75D Current limitation A per channel 5 10 20 CEDRAT TECHNOLOGIES 28 Version 1 0 0 11 04 14 ANNEX 3 SA75A X TECHNICAL DATA SHEET Table of standard properties of use and measurement The properties defined in the table below are set up according to the technical conditions of use and measurement These properties are warranted within their variation range and in compliance with the standard technical conditions of use SA75 Product and Warranty information
29. ts A B D version and Y represents 1 or 2 channels as well as sensors conditioning units e Strain gauges sensors conditioner SG75 unit e Eddy current sensors conditioner ECS75 unit And servo controllers e UC45 on the SA75 board e UC65 on specific position The rear panel includes the main power connection the ON OFF switch and the fuses The front panel includes the connections with actuators orders the switches to close the loop SERVO and the led indications regarding faults Cf Figure 1 The rack can include other boards described in separate documentations CEDRAT TECHNOLOGIES 5 Version 1 0 0 11 04 14 SA75 Product and Warranty information A1 A2 A3 A7 A6 Figure 1 Front panel of the SA75 power supply Each item is described in the next table Nota X refers to the A B or D version of the driving electronics REFERENCE DESIGNATION 1 module Main power supply unit SC75 A1 Over Voltage This diode lights when the amplifier detects an overvoltage on the actuator A2 Over Current This diode lights when the amplifier detects an overcurrent A3 Over Temp This diode lights when the actuator or the amplifier reachs the maximum temp A6 Led power supply presence green Led protect red A7 Power On Switch ee 2 module Switching amplifier SA75X B2 Order BNC connector channel 1 B3 DC offset order potentiometer 10 turn screw channel 1 B4 Closed loop selector SERVO ON OFF channel 1
30. xternal analogue order Reading of the calibration parameters of the sensor using the TEDS functionality For further details see the user s manual for the UC45 controller Additionally UC65 controller board can be integrated to improve the sampling rate 8 2 Terms and definition Resolution the resolution is the smallest displacement that the sensor and its conditioning electronic is able to measure The resolution is preferably given with a relative value a percentage of the total range of measurement Precision error in closed loop the precision error is the difference between the command and the effective value of the displacement Several contributors play a role in the precision error resolution of the sensor sensitivity to external parameters ageing temperature corrector error The precision error is preferably given with a relative value a percentage of the total displacement The following table gives the performances of the position sensor Sensor type Resolution Precision error Most contributing factors Strain Gauge SG 10 10 Temperature Eddy Current Sensor 10 104 Temperature material ECS of the target Capacitive sensor CS 107 5107 Tilt effect between the target and the probe Humidity CEDRAT TECHNOLOGIES 22 Version 1 0 0 11 04 14 SA75 Product and Warranty information Table 1 Performances of the sensors 8 3 Synoptic Ch
Download Pdf Manuals
Related Search