Test Equipment: HTA-3300 Three-phase Digital Intelligent High-Current Source, HTV-6000 Three-phase Digital Intelligent High-Voltage Source, YD-300 Wireless Telemetry Voltage-Current Phase Indicator

Test Project: Line Phasor Check Before Commissioning of a Newly Added Line in a 500kV Smart Substation

I Wiring Modes

1) High-Voltage Source Wiring

Considering the risks of applying high voltage on the primary side, a low voltage of 57.7V is input from the secondary side of the merging unit cabinet as the reference voltage.

2) High-Current Source Wiring

Open the isolation switch 1G and the earthing switch 1GD, and earth the P2 terminal.

Connect the HTA-3300 Three-phase Digital Intelligent High-Current Source to the P1 terminal for three-phase current input (IA, IB, IC).

Earth the P2 and IN terminals to form a closed circuit.

△ Wiring Schematic of Three-phase Digital High-Current Source

△ Secondary Wiring of High-Voltage Source Merging Unit

△ On-site Wiring Layout of HTA-3300 Three-phase Digital Intelligent High-Current Source

△ Primary Injection with HTA-3300 Three-phase Digital Intelligent High-Current Source

II Test Method

Power on and operate the AC 380V power supply for the three-phase digital high-current source and the AC 220V power supply for the three-phase digital high-voltage source, and set the remote control operation mode.

Realize wireless operation via the YD-300 Wireless Telemetry Voltage-Current Phase Indicator while ensuring the synchronization of the output voltage and current.

The remote control host automatically searches for and connects to the high-current source and high-voltage source. Then set the different amplitudes of each phase current and voltage, and the phase relationship between current and voltage as required on the software interface of the YD-300.

After verifying the correctness of all wiring and software settings, start the primary injection: inject the secondary voltage through the PT and the primary current through the CT.

Check the recovered amplitude and phase on the YD-300 to verify the entire secondary circuit and polarity.

The transformation ratio of the CT protection winding in this substation is 1200A/1A.

1) Parameter Setting on the Remote Control Host

Set the three-phase current output to 120A and the three-phase voltage output to 57.735V, with specific parameters as follows:

Item	Amplitude (V/A)	Phase (°)
UA	57.735V	0
UB	57.735V	240
UC	57.735V	120
IA	120A	0
IB	120A	240
IC	120A	120

2) Test Execution and Result Verification

Click Start Test; the high-current source and high-voltage source start outputting, and read the corresponding values on the YD-300 Wireless Telemetry Voltage-Current Phase Indicator.

Convert the applied primary current to the secondary current: 120A/1200 = 0.1A, which is basically consistent with the sampling amplitude on the YD-300.

The three-phase phase is in positive sequence, and the sampling amplitude and phase displayed on the protection device are consistent with those on the YD-300.

Conclusion: The secondary circuit, phase sequence, phase and polarity of this bay are all correct.

III Test Report

During the on-site test, multiple groups of primary voltage and current with different amplitudes and phases were applied. The secondary values recovered on the remote control host of the YD-300 were basically consistent with those displayed on the protection device, and all test data were normal. The results of multiple tests are shown in the table below:

IV Test Summary

1. For newly-built substations or newly added bays, direct injection of primary current and voltage facilitates the inspection of the entire primary/secondary circuit, as well as polarity and phase. It solves the problem of polarity verification without load in traditional methods and improves the reliability of one-time power transmission.
2. The test equipment can apply voltage either on the primary side or the secondary side, providing a phase reference for the primary current output.
3. Compared with traditional current boosters, the test equipment features a greatly reduced volume and weight for convenient on-site movement. Unlike traditional single-phase high-current output current boosters, this equipment can output three-phase high current simultaneously; the ABC three-phase wiring can be completed in one go, saving wiring replacement time and improving work efficiency.
4. The test equipment can arbitrarily adjust the amplitude of primary output current (0~300A) and primary output voltage (0~6000V), as well as the three-phase phase (0~360°), and the output amplitude can be set according to on-site requirements.