The GIS (gas-insulated switchgear) partial discharge test is an important means to evaluate its insulation performance, which can effectively find the potential defects in the equipment. The following are the detailed steps and precautions for the GIS partial discharge test
I. Purpose of the test
Detect partial discharge in the GIS and evaluate the health of the insulation system to ensure the safe operation of the device.
Second, test equipment
Partial discharge detector: Used to measure and record partial discharge signals.
High voltage test transformer: provides the high voltage required for the test.
Coupling capacitors are used to transmit partial discharge signals.
Calibration pulse generator: Used to calibrate partial discharge detection systems.
Shielded chambers or shielded cables: Reduce external electromagnetic interference.
3. Test steps
Preparatory work
Check the appearance of the GIS device.
Confirm the safety of the test area and set up warning signs.
Connect the test equipment to ensure the wiring is correct and firm.
Calibration system
The calibration pulse generator is used to calibrate the partial discharge detection system to ensure the measurement accuracy.
Applied voltage
Gradually increase the voltage to the test value (usually 1.1 to 1.2 times the rated voltage of GIS) to avoid sudden pressurization.
Keep the test voltage stable and observe the partial discharge signal.
Detection and recording
The partial discharge detector is used to collect signals and record parameters such as discharge quantity and discharge frequency.
Analyze the signal characteristics to determine whether partial discharge exists.
End the test
Gradually reduce the voltage to zero and disconnect the test power supply.
Collate test data and issue test report.
4. Precautions
Environmental requirements: The test environment should be dry and free from strong electromagnetic interference.
Safety protection: Operators should wear insulation equipment, and non-related personnel should not enter the test area.
Equipment inspection: Before the test, ensure that the equipment is in good condition and the wiring is correct.
Data analysis: Combined with equipment operation history, a comprehensive analysis of test results is needed to avoid misjudgment.
5. Evaluation of test results
Normal conditions: local discharge capacity is lower than the standard limit, no obvious discharge signal.
Abnormal situation: The local discharge capacity exceeds the standard, or abnormal signals occur. Check the insulation status of the device.
Through the above steps, the GIS partial discharge test can be accurately completed, which provides a reliable guarantee for the safe operation of the equipment.