500kV电容式电压互感器故障原因分析

Cause Analysis of 500kV Capacitor Voltage Transformer Failure

针对500kV TYD3500/√-0.005H型电容式电压互感器单相失压问题,通过对电容式电压互感器进行试验和设备解体,分析其故障原因,指出中间变压器进水受潮,导致绕组间短路、匝间短路等故障状态,是该电感器电磁单元油品劣化、二次失压的原因。结合日常巡视和高压试验方法提出了相应预防措施,为同类设备的安靠运行提供指导性的建议。

Aiming at the single-phase voltage loss of 500 kV TYD3500/√-0.005 Htype capacitive voltage transformer,the high voltage test of the capacitive voltage transformer and the disassembly of the equipment were used to analyze the cause of the failure.It was pointed out that the reason of oil deterioration and secondary voltage loss of the electromagnetic unit of the voltage transformer was that the water in the intermediate transformer was affected by moisture,which lead to winding short circuit and turn to turn short circuit.Combining daily inspections and high-pressure test methods,corresponding preventive measures were proposed to provide guidance for the safe and reliable operation of similar equipment.