500kV电容式电压互感器故障分析  

Fault Analysis of 500 kV Capacitive Voltage Transformer

作　　者：郭鹏 张彦军 曹懿 GUO Peng;ZHANG Yanjun;CAO Yi(Baotou Power Supply Company,Baotou 014030,China)

机构地区：[1]包头供电公司,内蒙古包头014030

出　　处：《电工技术》2024年第8期184-186,共3页Electric Engineering

摘　　要：某变电站后台机显示一路500 kV出线电压不平衡。停电该线路后,对该线路三相电压互感器进行诊断试验,试验结果表明,B、C相各项试验均合格,A相下节电容量和变比数据异常。初步判断A相电压互感器下节油质受潮或部分电容元件短路。通过解体试验,确定故障原因为A相下节从上至下第四片电容芯子塑料膜破损,电容芯子已击穿,导致电容量增大,进而影响变比。The backend machine of a substation showed an inequilibrium voltage of a 500 kV outgoing line.A diagnostic test with power outage was carried out on the line's three-phase voltage transformer,whose result showed that all tests for phase B and phase C were qualified,and capacitance and voltage ratio data of the lower section of phase A were abnormal.It was then preliminarily determined that the lower section oil of phase A voltage transformer suffered damp or sectional capacitor elements encountered short circuited.Through disassembly test,it was confirmed that the fault cause is the damage of plastic film of the fourth capacitor core from top to bottom of the lower section of phase A,and the breakdown of capacitor core,which led to the increase of capacitance,thus affected the change of voltage ratio.

关 键 词：电压互感器 电容量 变比 诊断试验 解体试验 

分 类 号：TM451[电气工程—电器]