Distance protection devices are usually set with impedance or reactance as fixed values. Taking the commissioning of the CSC-101A line protection device (set with reactance as fixed values) using the Relaystar-1600 Relay Protection Tester as an example, this paper introduces how to use the distance and zero-sequence test module to more quickly and efficiently complete the three-stage fault simulation test of line protection ground distance.

1. Protection Fixed Value and Press Plate Settings

2. Test Wiring

△ Relaystar-1600 Relay Protection Tester

△ Pilot Distance Protection Wiring Diagram

Connect the voltage output terminals “Ua”, “Ub”, “Uc” and “Un” of the Relaystar-1600 to the AC voltage terminals “UA”, “UB”, “UC” and “UN” of the protection device respectively.Connect the current output terminals “Ia”, “Ib” and “Ic” of the Relaystar-1600 to the AC current terminals “IA”, “IB” and “IC” (polar terminals) of the protection device respectively.Short-circuit the AC current terminals “IA’”, “IB’” and “IC’” (non-polar terminals) of the protection device, then connect them to the “IN” (zero-sequence current polar terminal) terminal. Finally, connect back from the “IN’” (zero-sequence current non-polar terminal) terminal to the current output terminal “IN” of the Relaystar-1600.

Connect the input contact “A” of the Relaystar-1600 to the phase-separated trip output contact “Trip A” of the protection device, and connect the “+KM” terminal of the Relaystar-1600 to the common terminal of the protection device. The switch position corresponding to the line here is “closed”, and the output wiring is not considered.

3. Ground Distance Protection Function Verification

1) Parameter Settings

Open the Distance and Zero-sequence Protection menu, check Distance Protection in the test items, set the pre-fault delay to 12s to ensure the TV disconnection alarm is eliminated. Keep the default values for the test interval time and maximum auto-reclosing delay. Select Time Trigger as the trigger mode and Phase-separated Trip as the trip mode. Choose Kr/Kx Mode for the zero-sequence compensation coefficient, with Kr set to 0.930Ω and Kx set to 0.470Ω.

△ Parameter Settings

Enter the Distance Protection Test Interface and set parameters according to the setting sheet: select Φ as 90°, set the test time to generally 0.1–0.2s longer than the fixed value time, check Ground Short-circuit Impedance Zone I, II & III, select R-X as the grounding mode, choose Phase A Grounding as the fault type, and set the test impedance multiples to 0.95 times and 1.05 times.

△ Distance Protection Parameters

Enter the Test Parameters interface for configuration: select Phase-separated Trip, set PT installation location as bus side and CT installation location as line side.

△ Test Parameters

2) Test Method

Click Start and the Relaystar-1600 starts outputting. First, output voltage to eliminate TV disconnection, then output fault status. The protection trips reliably, and the input contact collects the operation time.Complete the setting of 0.95 times and 1.05 times the impedance values for Distance Protection Zone I, II and III in sequence. After the protection test is completed, select whether to save the test results according to the prompt.

△ No-load Output for 12s to Eliminate TV Disconnection

4. Test Results

After the test, the input quantity records the test operation information, and the protection device displays that the distance protection has operated.

△ Operation Status of Ground Distance Protection Zone I, II & III

△ Test Results

The ground distance protection Zone I, II and III operate reliably when the short-circuit impedance is 0.95 times the setting value, and remain reliably inoperative when the short-circuit impedance is 1.05 times the setting value. In the event of Phase A grounding, Zone I and II trigger single-phase tripping while Zone III triggers three-phase tripping, indicating that the test results on the protection device are correct.Checking the test results displayed on the tester shows that the operation status and operation time information of the ground distance protection under various fault types are accurate.