Transformer Protection Simulation User Manual /
Hardware and Relay Configuration Guide /
Nicholas Kilburn /

11/15/2018

This manual details the configurations and methods to replicate the Transformer Protection Simulation developed as a part of the SEL Protection and Monitoring thesis project of 2013.

Contents

Hardware Configuration

Relay Configuration

Hardware

Configuration

Simulation Operation

Appendix

Hardware Configuration

Figure 1 - Lab-Volt Simulation SLD

  • Connect the Lab-Volt Equipment as per the diagram in Figure 1.
  • For the Primary CTs use the 2.5:5 ratio
  • For the Secondary CTs use the 1:5 ratio
  • Ensure the CTs are not shorted, i.e. the associated switches are set off.
  • For the load set the per phase resistance to 686Ω, set all resistor switches on
  • Connect the grounding points to the neutral of the power supply to avoid earth-leakage tripping of the three-phase main supply.

See the appendix images for visual representation of this simulation connections structure and a larger version of Figure 1.

Relay Configuration

Hardware

Figure 2 - Relay Connections

  • Connect the relay I/O terminals as illustrated in Figure 2
  • Ensure that the connections to the interconnection panel match those leading to the Lab-Volt system
  • Z01 to Z12 inputs for the CT secondaries
  • A05 to A08 are the outputs for breaker control
  • A09 to A12 provide the inputs for breaker monitoring
  • Make sure the correct power is connected to A01 and A02, 120V approximately.

Configuration

Step 1.To configure the relay first open the AcSELerator Quickset application, connect the relay to the PC serial communication port and establish a connection as detailed in the “AcSELerator Quickset User Manual”.

Step 2.Once this is complete open the settings editor either directly from the relay or from the local database, if a new settings editor is established then all configuration settings will need to be addressed.

Step 3.Ensure that the configuration settings are configured as follows (Table 1); adjust as necessary for any changes in simulation configuration.

  1. If simulation has been modified, follow steps 1 through 4 in the Simulation Operation section before proceeding to step 4.
  2. These configurations fit the original simulation as designed in 2013.

Table 1 - Default Simulation Relay Configuration

Level 1 / Level 2 / Level 3 / Level 4/5 / Name / Setting
Global
General / PHROT / ABC
FNOM / 50
DATE_F / DMY
FAULT / 51P1P OR 51P2P OR 51G1P OR 51G2P OR 51N1P OR TRIP
Event Messenger
EMP / N
Settings Group Selection
SS1 / 1
Synchronized Phasor Measurement
EPMU / N
Breaker Failure
52ABF / N
Through-Fault Monitor
THFLTD / N
Input Debounce
Slot A
IN101D / 100
IN102D / 100
Group 1
Set 1
Configuration
MVA / OFF
ICON / N
W1CT / DELTA
CTR1 / 1
W2CT / WYE
CTR2 / 1
Transformer Differential Elements
E87 / N
TAP1 / 4.76
TAP2 / 3.04
O87P / 0.3
87AP / 0.15
87AD / 5
SLP1 / 25
SLP2 / 70
IRS1 / 3
U87P / 6
PCT2 / 15
PCT4 / 15
PCT5 / 35
TH5P / OFF
HRSTR / Y
HBLK / N
Overcurrent Elements
Winding 1
Phase Overcurrent
50P11P / 1.12
50P11D / 0.1
50P11TC / 1
50P12P / OFF
50P13P / OFF
50P14P / OFF
Negative Sequence Overcurrent
50Q11P / 0.1
50Q11D / 0.2
50Q11TC / 1
Winding 2
Phase Overcurrent
50P21P / 1.56
50P21D / 0.1
50P21TC / 1
50P22P / OFF
50P23P / OFF
50P24P / OFF
Residual Overcurrent
50G21P / 0.1
50G21D / 0.1
50G21TC / 1
50G22P / OFF
Negative Sequence Overcurrent
50Q21P / 0.1
50Q21D / 0.2
50Q21TC / 1
50Q22P / OFF
Time Overcurrent Elements
51P1P / OFF
51G1P / OFF
51Q1P / OFF
51P2P / OFF
51G2P / OFF
51Q2P / OFF
Trip and Close Logic
TDURD / 0
TRXFMR / 87R OR 87U
REMTRIP / 0
ULTRXFMR / NOT (87R OR 87U)
CFD1 / 1
TR1 / 50P11T OR 50G11T OR 50Q11T OR NOT LT02 AND SV04T OR OC1
ULTRIP1 / NOT ( 50P11P OR 50G11P OR 50Q11P OR 51A1 )
52A1 / NOT IN101
CL1 / SV03T AND NOT LT02 OR CC1
ULCL1 / TRIP1 OR TRIPXFMR
CFD2 / 1
TR2 / 50P21T OR 50G21T OR 50Q21T OR NOT LT02 AND SV04T OR OC2
ULTRIP2 / NOT ( 50P21P OR 50G21P OR 50Q21P OR 52A2 )
52A2 / NOT IN102
CL2 / SV03T AND NOT LT02 OR CC2
ULCL2 / TRIP2 OR TRIPXFMR
Logic 1
Outputs
Slot A
OUT101FS / Y
OUT101 / HALARM OR SALARM
OUT102FS / N
OUT102 / TRIP1 OR TRIPXFMR
OUT103FS / N
OUT103 / TRIP2 OR TRIPXFMR

Notes:

  • NOT of elements 52A1 and 52A2 is to account for the NC contract from the control relays feeding the Breaker status monitor.
  • Element E87 will need to be enabled (Y) to allow the settings to be modified to avoid settings download errors.
  • Protective Functionality can be disabled by setting the required XXXX1P overcurrent elements to OFF.

Step 4.Once the configurations are confirmed, the settings can be downloaded to the relay through selection of the Send Active Settings button.

Simulation Operation

The process described should result in the configuration settings defined in Table 1, assuming no changes to the simulation have been made.

  1. Ensure all protective functionality is disabled by setting all XXXXXP overcurrent elements to OFF and disable differential protection.
  2. Check that all fault inducing switches or buttons are in their off positions, this can cause
  3. Nominal configuration errors, or
  4. Trip the three-phase earth-leakage breaker (any ground fault).
  5. Turn on the DC control relays power supply; the three-phase contactors in the transmission grid should close.
  6. Set the Lab-Volt Power supply to 50% and turn on.
  7. Use the Relay HMIPhaosr and Differential Elements windows to record nominal CT secondary current readings for all phases and the nominal differential elements.
  8. Use this data to establish the pickup levels for Phase Overcurrent and Differential Protection.
  9. Set the Phase Overcurrent pickup elements to be 10% on the nominal metered current, as seen by the relay. For Residual and Negative-Sequence Elements set the Pickup to the smallest permissible without causing trip conditions during nominal operation.
  10. The configuration of time delays is entirely up to the user.
  11. Calculate the TAP elements using the following formula:, Where:
  12. This calculation, using the actual values will produce results that will result in errors, to avoid this multiply the results by a suitable factor to bring these calculations into a configurable range.
  13. Adjust any settings that become erroneous as a result of this calculation to avoid download errors.
  14. More details of this process can be observed within the Thesis Report in sections 6.2.3 and 7.5.2.
  15. Enable the required protective functions and download new settings to the relay.
  16. Connect the required power to the Universal Fault Module and connect the Line-to-Line Fault, series connected with an available contact output, across two phases of the load or any other point in the simulation.
  17. Power the Lab-Volt system (still at 50%) and DC control relay power supply.
  18. Begin fault testing by conducting any number of the following:
  19. Depressing the initiate fault button on the Universal Fault Module
  20. Disconnecting a phase of the Load
  21. Temporarily increase the three-phase Power Supply (greater than 50%)
  22. Initiate faults on the Faultable Transformer Module.
  23. At this stage do not introduce a fault to ground
  24. The three-phase earth-leakage circuit breaker will trip disconnecting the power to the Lab-Volt system before the relay has a chance to respond to the fault.
  25. After the introduction of a fault the relay will respond and trip the appropriate contactors, the front panel will:
  26. Describe the type of fault
  27. Indicate the winding to generate the fault
  28. Visually indicate which breakers have opened as a result

The response will vary depending on which fault mechanism was utilised and what protective functionality was enabled during the fault event.

  1. To re-close the three-phase contactors push the desired and illuminated reset button on the control relay panel. The relay should reset the trip condition and allow the contactors to remain closed.
  2. On occasion the relay may instantaneously re-open the contactor(s) upon reset attempt; this usually happens as a result of residual currents within the Delta transformer and can be resolved by holding the reset button for an extended period to allow the system to settle before the relay can generate a trip condition.
  3. This occurrence can also be avoided by introducing a delayed tripping response, to account for the system settling or any remaining start-up transient currents within the delta winding.
  4. The use of the EVENT, SUM and EVE DIF1 commands in the terminal command window will provide fault event metering data and before, during and after metering screenshots detailing the fault generation and relay response. This is the easiest mechanism to observe the nature of the induced faults and their impact upon the system.
  5. After simulations are complete turn off all power supplies for the Lab-Volt system, then turn off relay at rear mains switch.

Appendix