Automatic tap changer controller function block description
Contents
1. EURO P ROT sF Automatic tap changer controller function block description PROTEC A IED EP Automatic tap changer controller User s manual version information Version Date Modification Compiled by Preliminary 24 11 2010 Preliminary version without technical information Petri V1 0 13 12 2010 First edition Petri V1 1 20 12 2012 Corrected formula for complex compensation Petri V1 2 29 01 2013 Error code added Petri VERSION 1 2 2 14 IED EP Automatic tap changer controller CONTENTS 1 Automatic tap changer controles uressieicnearinai i 4 a ey App CaO aa reer terre ere T a rere retest ere 4 1 2 Mode of operation 2cc ccc2i aden ieesiinaedd iaaa aE aaae 4 1 2 1 The scheme of the function block essseesssssesssrnnsssrnessnnnsnnnnastnnnnnnnnnnnnnnnnnnnnnnnnnna 4 1 2 2 Analog inputs of the controller fUNCtION eee cece eeteee ee eeeeeeeeeeeeeeeeeeteaeeeeeeeaeens 4 1 2 3 Internal checks before control Operation cc ceeeseeeeeeeeeeeeeeeeeeeeaeeeeeeaeeeeeeaees 4 122 4 A tomaticcontrol MOOG ia fee receedet sv edswes Pecpec chs ondOees rertiene netted epted hd a Oke eee ee eres 6 1 2 5 Manual contol mode sesar acspedspdcveeheaceuesdeades 8 1 2 6 Command generation and tap changer SUPerViSiON ccceeeeeteeeeeteeteeeeeeees 9 1 2 7 ENO COOGS oi r T A ates feecasee secon ee 9 13 Technical SUMIMALY sccccecscecedseccceceesccecediaccecee2. low ATCC_UBlock_Grl_ U Block Blocked state for too low voltage ATCC_IHigh_Grl_ High Blocked because of current limit ATCC_Locked_Grl_ Locked The supervision detected tap changer error the blocking can be released exclusively by the Reset impulse Controlling to reduced voltage 1 Controlling to reduced voltage 2 ATCC_VRed1_Grl_ ATCC_VRed2_Grl_ Voltage Reduction 1 Voltage Reduction 2 Table 1 7 Binary output status signals of the breaker failure protection function 1 3 4 Summary of the input signals Binary status signals The automatic tap changer controller function has binary input status signals The conditions are defined by the user applying the graphic equation editor The binary input status signals of the automatic tap changer controller function are listed in the table below Binary status signal Title Explanation ATCC Local _GrO_ Local Local state of the manual operation ATCC_Remote_GrO _ Remote Remote state of the manual operation ATCC Blk_GrO_ Blk Blocking of the function ATCC _AutoBlk_GrO_ AutoBlk Blocking of the automatic function ATCC Manual GrO _ Manual Manual mode of operation ATCC_ManHigher_GrO__ ManHigher Manual command for increasing the voltage ATCC ManLower_GrO__ ManLower Manual command for decreasing the voltage ATCC BitO GrO_ Bito Bit 0 of the position indicator ATCC Bit1_GrO_ Biti Bit 1 of the position indic
3. side IHV is above the limit set by the parameter I Overload then both automatic and manual controls are completely disabled This is to protect the switches inside the tap changer VERSION 1 2 4 14 IED EP Automatic tap changer controller UL1L2 mnt UBlock ial IHigh IL1L2 Manual oe Higher Command Lower Command diii MaxPosReached MinPosReached ManLower BitO Rie Locked TCRun Reset Local Remote Manual COMMUNICATION AutoBlocked AutoBlk VRed1 VRed1 VRed2 VRed2 Figure 1 1 The logic schema of the automatic tap changer controller VERSION 1 0 5 14 IED EP Automatic tap changer controller 1 2 4 Automatic control mode Voltage compensation in automatic control mode The module AUTO in Figure 1 1 gets the Fourier components of the busbar voltage and those of the current e UL1L2p and ULIL2m e IL1L2p and IL1L2 m In automatic control mode the voltage of the controlled side UL1L2 is compensated by the current of the controlled side L1L2 This means that the voltage of the load center of the network is controlled to be constant in fact within a narrow range This assures that neither the voltage near to the busbar is too high nor the voltage at far away points of the network is too low The voltage of the load center i e the controlled voltage is calculated as Ucontrol Ubus Udrop There are two compensation modes to be selected AbsoluteComp and ComplexComp
4. Compound Factor is a parameter value VERSION 1 0 6 14 IED EP Automatic tap changer controller The voltage of the load center of the network is controlled to be within a narrow range This assures that neither the voltage near to the busbar is too high nor the voltage at far away points of the network is too low The method is based on the estimated complex impedance between the busbar and the load center The parameter R Compound Factor means in this case the voltage drop in percent caused by the real component of the rated current The parameter X Compound Factor means in this case the voltage drop in percent caused by the imaginary component of the rated current NOTE if the active power flows from the network to be controlled to the busbar then in AbsoluteComp mode no compounding is performed Voltage checking in automatic control mode In automatic control mode the calculated Ucontro voltage is checked to see if it is outside the limits The limits are defined by parameter values U Set is the setting value defining the centre of the permitted range U Deadband is the width of the permitted range in both and directions Deadband Hysteresis is the hysteresis decreasing the permitted range of the U Deadband after the generation of the control command If the calculated Ucontrol voltage is outside the limits then timers are started In an emergency state of the network when th
5. a of the automatic tap changer controller function 1 3 2 Summary of the parameters Enumerated parameters Parameter name Title Selection range Default Control model according to IEC 61850 ATCC_ctIMod_EPar_ ControlModel Direct normal Direct enhanced Direct SBO enhanced normal Select before operate class according to IEC 61850 ATCC_sboClass_EPar_ sboClass Operate once Operate many Operate once Parameter for general blocking of the function ATCC_Oper_EPar_ Operation Off On Off Parameter for time delay mode selection ATCC_TiType_EPar_ T1 Delay Type Definite Inverse 2powerN Definite Selection for compensation mode ATCC_Comp_EPar_ Compensation Off AbsoluteComp ComplexComp Off Tap changed supervision mode selection ATCC_TCSuper_EPar__ TC Supervision Off TCDrive Position Both Off Decoding of the position indicator bits ATCC_CodeType EPar CodeType Binary BCD Gray Binary Table 1 2 Enumerated parameters of the automatic tap changer controller function VERSION 1 0 10 14 IED EP Automatic tap changer controller Boolean parameters Parameter name Title Default Explanation ATCC_FastHigh_BPar_ Fast Higher Enable 0 Enabling fast higher control command ATCC _FastLow_BPar_ Fast Lower Enable 0 Enabling fast lower control command Table 1 3 The Boolean parameters of the automatic t
6. ap changer controller function Integer parameters Parameter name Title Unit Min Max Step Default Code value of the minimum position ATCC _MinPos Par_ Min Position 1 32 1 1 Code value of the maximum position ATCC_MaxPos Par_ Max Position 1 32 1 32 Table 1 4 Integer parameters of the automatic tap changer controller function Timer parameters Parameter name Title Unit Min Max Step Default Time limit for tap change operation ATCC_TimOut_TPar_ Max Operating msec 1000 30000 1 5000 Time Command impulse duration ATCC Pulse _TPar_ Pulse Duration msec 100 10000 1 1000 Time overbridging the transient state of the tap changer status signals ATCC_MidPos_TPar Position Filter msec 1000 30000 1 3000 Select before operate timeout according to IEC 61850 ATCC_SBOTimeout_TPar_ SBO Timeout msec 1000 20000 1 5000 Table 1 5 Timer parameters of the automatic tap changer controller function VERSION 1 0 11 14 IED EP Automatic tap changer controller Float parameters Parameter name Title Unit Min Max Digits Default Factor for fine tuning the measured voltage ATCC_Ubias_FPar_ U Correction 0 950 1 050 3 1 000 Set point for voltage regulation related to the rated voltage Valid at l 0 ATCC_USet_FPar_ U Set 80 0 115 0 1 100 0 Dead band f
7. ator ATCC Bit2 GrO_ Bit2 Bit 2 of the position indicator ATCC Bit3 GrO_ Bit3 Bit 3 of the position indicator ATCC Bit4 GrO_ Bit4 Bit 4 of the position indicator ATCC BitS GrO_ Bit5 Bit 5 of the position indicator ATCC_TCRun_GrO_ TCRun Running state of the tap changer ATCC Reset GrO_ Reset Reset to release from blocked state ATCC_BIkProc_GrO_ BlkProc Blocking signal from the tap changer ATCC _VRed1_GrO __ VRed1 Reduced voltage 1 is required ATCC _VRed2_GrO __ VRed2 Reduced voltage 2 is required Table 1 8 Binary input signals of the breaker failure protection function VERSION 1 0 13 14 IED EP Automatic tap changer controller 1 3 5 The symbol of the function block in the graphic editor The names of the input and output signals are parts of the Binary status signal names listed in the previous paragraph VERSION 1 0 14 14
8. cremented in case of a voltage decrease within the Max Operating Time e Both in this mode the previous two modes are combined In case of an error detected in the operation of the tap changer the Locked input becomes active and no further commands are performed To enable further operation the input Reset must be programmed for an active state by the user 1 2 7 Error codes The On line information includes a variable ErrorCode ATCC_ErrCode_ISt_ indicating different error states These states are binary coded any of them causes Locked state of the controller function The explanation of the individual bits in the code value is explained in the Table below Bit Value Explanation 0 1 Drive started without control command 1 2 Drive did not start after control command 2 4 Drive did not stop in due time 3 8 Invalid position signal 4 16 Position signal did not change value In case of multiple error states the values are added in the ErrorCode VERSION 1 0 9 14 IED EP Automatic tap changer controller 1 3 Technical summary 1 3 1 Technical data Function Range Accuracy Voltage measurement 50 lt U lt 130 lt 1 Definite time delay lt 2 or 20 ms whichever is greater Inverse and 2powerN time delay 12 lt AU lt 25 lt 5 25 lt AU lt 50 lt 2 or 20 ms whichever is greater Table 1 1 Technical dat
9. d generation ATCC_T1_FPar_ Ti sec 1 0 600 0 1 10 0 Definite time delay for subsequent control command generation or fast operation if it is enabled ATCC_T2_FPar_ T2 sec 1 0 100 0 1 10 0 In case of dependent time characteristics this is the minimum time delay ATCC _MinDel_ FPar_ Min Delay sec 1 0 100 0 1 10 0 After a control command if the voltage is out of the range within the reclaim time then the command is generated after T2 time delay ATCC_Recl_FPar_ Reclaim Time sec 1 0 100 0 1 10 0 Table 1 6 Float parameters of the automatic tap changer controller function VERSION 1 0 12 14 IED EP Automatic tap changer controller 1 3 3 Summary of the generated output signals The binary output status signals of the breaker failure protection function are listed in the table below Binary status signal Title Explanation ATCC_AutoBlocked_Grl_ Auto Blocked ext Automatic control blocked ATCC_Manual_Grl_ Manual Signaling the manual mode of operation ATCC_HigherCmd_Grl_ Higher Command Command for increasing the voltage ATCC_LowerCmd_Grl_ Lower Command Command for decreasing the voltage ATCC_MaxReached_Grl__ Max Pos Reached Signaling the maximal position ATCC_MinReached_Grl_ Min Pos Reached Signaling the minimal position ATCC_UHigh_Grl_ U High Voltage is high ATCC_ULow_Grl_ U Low Voltage is
10. e f the parameter Compensation is set to AbsoluteComp the calculation method is as follows In this simplified method the vector positions are not considered correctly the formula above is approximated with the magnitudes only Ucontrol Ubus Udrop Ubus Udrop x Ubus I R CompoundFactor Where R Compound Factor is a parameter value If the current is above the value defined by the parameter I Comp Limit then in the formulas above this preset value is considered instead of the higher values measured The method is based on the experiences of the network operator Information is needed how much is the voltage drop between the busbar and the load center if the load of the network is the rated load The parameter R Compound Factor means in this case the voltage drop in percent e f the parameter Compensation is set to ComplexComp the calculation method is as follows In this simplified method the vector positions are partly considered In the formula above the voltage drop is approximated with the component of the voltage drop the direction of which is the same as the direction of the bus voltage vector This is length component of the voltage drop the perpendicular component of the voltage drop is neglected Ucontrol Ubus UL1L2p jIL1L2 R CompoundF actor jXCompoundFactor Where R Compound Factor is a parameter value X
11. e network elements are overloaded the Uset value can be driven to two lower values defined by the parameters Voltage Reduction 1 and Voltage Reduction 2 U Set is decreased by the parameter values if the binary inputs Voltage Reduction 1 or Voltage Reduction 2 enter into active state These inputs must be programmed graphically by the user U U HighLimit Deadband Hysteresis UDeadband U Set U Deadband Deadband Hysteresis U Low Limit U Low Block Figure 1 2 Voltage level settings VERSION 1 0 7 14 IED EP Automatic tap changer controller Time delay in automatic control mode In automatic control mode the first and every subsequent control command is processed separately For the first control command The voltage difference is calculated Udiff Ucontrol Uset If this difference is above the U Deadband value then depending on the setting of parameter T1 Delay Type three different timing modes can be selected e Definite this definite time delay is defined by parameter T1 e Inverse standard IDMT characteristic defined by the parameters o T1 maximum delay defined by the parameter o UDeadband is the width of the permitted range in both and directions o Min Delay minimum time delay Tdelay aa but minimum Min Delay Udeadband e 2powerN 1 IF Tdelay T1 2 Udeadband The binary parameters Fast Lower Enable and or Fast Higher Enable enab
12. le fast command generation if the voltage is above the parameter value U High Limit or below the U Low Limit In this case the time delay is a definite time delay defined by parameter T2 For subsequent control commands In this case the time delay is always a definite time delay defined by parameter T2 if the subsequent command is generated within the Reclaim time defined by parameter The automatic control mode can be blocked by a binary signal received via binary input AutoBlk and generates a binary output signal AutoBlocked ext 1 2 5 Manual control mode In manual mode the automatic control is blocked The manual mode can be Local or Remote For this mode the input Manual needs to be in active state as programmed by the user In the local mode the input Local needs to be in active state The binary inputs ManHigher or ManLower must be programmed graphically by the user In the remote mode the input Remote needs to be in active state as programmed by the user In this case manual commands are received via the communication interface VERSION 1 0 8 14 IED EP Automatic tap changer controller 1 2 6 Command generation and tap changer supervision The software module CMD amp TC SUPERV is responsible for the generation of the HigherCmd and LowerCmd command pulses the duration of which is defined by the parameter Pulse Duratio
13. n This is valid both for manual and automatic operation The tap changer supervision function receives the information about the tap changer position in six bits of the binary inputs Bit0 to Bit5 The value is decoded according to the enumerated parameter CodeType the values of which can be Binary BCD or Gray During switchover for the transient time defined by the parameter Position Filter the position is not evaluated The parameters Min Position and Max Position define the upper and lower limits In the upper position no further increasing command is generated and the output Max Pos Reached becomes active Similarly in the lower position no further decreasing command is generated and the output Min Pos Reached becomes active The function also supervises the operation of the tap changer Depending on the setting of parameter TC Supervision three different modes can be selected e TCDrive the supervision is based on the input TCRun In this case after command generation the drive is expected to start operation within one quarter of the value defined by the parameter Max Operating Time and it is expected to perform the command within Max Operating Time e Position the supervision is based on the tap changer position in six bits of the binary inputs BitO to Bit5 It is checked if the tap position is incremented in case of a voltage increase or the tap position is de
14. on can set the network voltage according to special requirements The automatic tap changer controller function can be applied to perform this task 1 2 Mode of operation 1 2 1 The scheme of the function block Figure 1 1 shows the scheme of the function block 1 2 2 Analog inputs of the controller function The automatic tap changer controller function receives the following analog inputs UL1L2 Line to line voltage of the controlled secondary side of the transformer IL1L2 Difference of the selected line currents of the secondary side of the transformer for voltage drop compensation IHV Maximum of the phase currents of the primary side of the transformer for limitation purposes The parameter U Correction permits fine tuning of the measured voltage 1 2 3 Internal checks before control operation In Figure 1 1 the block U I BLOCK performs the following checks before control operation e If the voltage of the controlled side UL1L2 is above the value set by the parameter U High Limit then control to increase the voltage is disabled e If the voltage of the controlled side UL1L2 is below the value set by the parameter U Low Limit then control to decrease the voltage is disabled e If the voltage of the controlled side UL1L2 is below the value set by the parameter U Low Block then the transformer is considered to be de energized and automatic control is completely disabled e f the current of the supply
15. or voltage regulation related to the rated voltage ATCC_UDead_FPar_ U Deadband 0 5 9 0 1 3 0 Hysteresis value for the dead band related to the dead band Deadband ATCC_DeadHyst_FPar_ Hysteresis o 60 90 0 85 Parameter for the current compensation See Chapter 1 2 4 i R Compound p ATCC_URinc_FPar_ actor Yo 0 0 15 0 1 5 0 Parameter for the current compensation See Chapter 1 2 4 X Compound b ATCC_UXinc_FPar_ Factor o 0 0 15 0 1 5 0 Reduced set point 1 for voltage regulation priority related to the rated voltage See Chapter 1 2 4 Voltage ATCC_VRed1_FPar_ Reduction 1 0 0 10 0 1 5 0 Reduced set point 2 for voltage regulation related to the rated voltage See Chapter 1 2 4 Voltage o ATCC_VRed2_FPar_ n 2 o 0 0 10 0 1 5 0 Maximum current value to be considered in current compensation formulas See Chapter 1 2 4 ATCC_ICompLim_FPar__ Comp Limit A 0 00 150 0 1 Current upper limit to disable all operation See Chapter 1 2 3 ATCC_IHVOC_FPar_ Overload 50 150 0 100 Voltage upper limit to disable step up See Chapter 1 2 3 ATCC_UHigh_FPar_ U High Limit 90 0 120 0 1 110 0 Voltage lower limit to disable step down See Chapter 1 2 3 ATCC_ULow_FPar_ U Low Limit 70 0 110 0 1 90 0 Voltage lower limit to disable all operation See Chapter 1 2 3 ATCC_UBlock_FPar_ U Low Block 50 0 100 0 1 70 0 Time delay for the first control comman
16. ssacdendincaceceypecteeduacdbere AE a aE AT 10 1 3 1 TECNICA dal d riea EE E AE 10 1 3 2 Summary of the parameters cccceeccceeeeeeeeeeeeeeeeeeeaeeeeeaeeeeeeeseeeeeseaeeseaeeseeeeess 10 1 3 3 Summary of the generated output signals cccceceeeeeeeeeeeeeeseeeeeeeaeeeeneeetaees 13 1 3 4 Summary of the input SiQnals ccccec cece eeeeeeceeeeeceeeeeaaeeeeeeeseeeesaeeesaeeeeeees 13 1 3 5 The symbol of the function block in the graphic editor eee eeeeeeeeeteeeeeeeee 14 VERSION 1 2 3 14 IED EP Automatic tap changer controller 1 Automatic tap changer controller 1 1 Application One criterion for power quality is to keep the voltage of selected points of the networks within the prescribed limits The most common mode of voltage regulation is the application of transformers with on load tap changers When the transformer is connected to different taps its turns ratio changes and supposing constant primary voltage the secondary voltage can be increased or decreased as required Voltage control can take the actual load state of the transformer and the network into consideration As a result the voltage of a defined remote point of the network is controlled assuring that neither consumers near the busbar nor consumers at the far ends of the network get voltages out of the required range The voltage control function can be performed automatically or in manual mode of operation the personnel of the substati
Download Pdf Manuals
Related Search