一起110kV电容式电压互感器异响原因分析

Cause Analysis of Abnormal Noise of a 110kV Capacitor Voltage Transformer

本文作者主要介绍了某供电局一台运行中的110kV电容式电压互感器出现异响,经检查发现该CVT电压监测数据偏高,通过对其进行诊断试验及解体检查,分析了故障产生原因。根据试验结果分析,判断造成该CVT异响的原因可能为中间变压器一次绕组存在接地短路的情况,使得补偿电抗器调谐作用失效,一定工况下激发CVT铁磁谐振,由于阻尼器对抑制谐振过电压的范围以及性能存在问题,从而导致产生持续的异响,并通过解体检查对故障原因进行了验证,为后续同类型设备的运行维护提供参考和指导。

This paper mainly introduces the abnormal noise of a 110kV capacitor voltage transformer in operation of a power supply bureau.It was found that the CVT voltage monitoring data was on the high side,and the cause of the fault was analyzed through diagnostic test and disassembly inspection.According to the test results,it is judged that the reason for the abnormal CVT noise may be that the primary winding of the intermediate transformer has a short circuit to ground,which makes the tuning function of the compensation reactor ineffective,and the CVT ferromagnetic resonance is excited under certain conditions.The damper has problems in the range and performance of suppressing resonant over-voltage,resulting in continuous abnormal noise.The failure causes were verified through disassembly inspection,providing reference and guidance for subsequent operation and maintenance of the same type of equipment.