抽水蓄能水电厂CVT二次电压偏低故障的原因分析

Cause Analysis on Low Secondary Voltage of Capacitor Voltage Transformer in Pumped Storage Power Station

本文首先简要说明了一起抽水蓄能水电厂 500 kV 电容式电压互感器(CVT)出现的二次电压值偏低的故障,并根据电容式电压互感器的结构特点及工作原理,对其进行了计算分析,初步判断故障是由于电容式电压互感器内部电容元件击穿引起的。在对设备进行解剖检查和试验分析后,发现电容式电压互感器内部 4 个电容元件击穿,证明了计算分析的正确性,找出故障所在,通过更换电容式电压互感器后,消除了故障,恢复供电后,二次电压恢复正常。最后提出了建议和防范措施,供运维、制造等单位参考。

In this paper,the faultof low secondary voltage of capacitor voltage transformer (CVT) in pumped storage power station is introduced firstly. The analysis and calculation is performed according to the structure feature and operating principle of the capacitor voltage transformer,judging preliminarily that the fault is due to breakdown capacitive component of the capacitor voltage transformer. It is found after disassembly inspection and test analysis of the equipment that four capacitive elements are breakdown. The correctness of the analysis is proved,the fault is found out,the fault is eliminated and power supply is recovered after replacement with new capacitor voltage transformer and the secondary power supply is recovered. Finally,the suggestion and preventions are proposed to the operation and manufacturer for reference.