How to Avoid the Impact of Environmental Factors on High-Voltage Test Results of Power Transformers

High-voltage testing is a necessary measure to ensure the safe operation of power transformers. During the high-voltage test of power transformers, environmental factors must be controlled to avoid their impact on the test results. Operators should perform transformer tests in accordance with relevant standards and regulations to ensure the safety and completeness of each high-voltage test step, thereby ensuring the safety and stability of power transformer operation, which can largely meet various operational requirements.

There are many reasons for winding faults in high-voltage test transformers during high-voltage testing. Therefore, after a winding fault occurs in a power transformer, operators are required to carefully inspect the power transformer and eliminate faults such as phase-to-phase short circuits, winding grounding, and turn-to-turn short circuits one by one. This ensures the safety and stability of power transformer operation, which can largely meet the requirements for power supply quality in various sectors of our society.

During the operation of a high-voltage test transformer, the frequency of the electromagnetic AC sound it produces is relatively stable. Therefore, during a high-voltage test of a power transformer, if an operator detects abnormal internal sounds, it may be due to overload operation, loose internal components, unclamped outermost silicon steel sheets of the core, loose top cover screws, poor internal contact, or short circuits in the power transformer, or large currents in the transformer windings. All these situations can cause abnormal internal sounds during high-voltage testing of power transformers. After such faults occur, operators can determine whether the transformer is faulty based on the internal sound. Once a fault is identified, operators should power off and inspect the aforementioned parts of the power transformer, and take reasonable measures to resolve the issue based on the cause of the fault.

If automatic tripping occurs during a high-voltage test of a high-voltage test transformer, operators need to determine the cause of the fault through external inspection. If the tripping is caused by operator error during the high-voltage test, no external inspection of the power transformer is required. However, if the tripping is not due to operator error, operators must conduct a thorough and comprehensive internal inspection of the power transformer to prevent fires during later use. If a fire occurs around the power transformer, automatic protection actions will be triggered, and the circuit breaker will be automatically disconnected to prevent damage to electrical equipment. If the power transformer does not automatically disconnect during a fire, manual operation is required to disconnect the circuit breaker for firefighting. This is also the main prerequisite for operating power transformers in fire situations.