一起500kV电容式电压互感器故障分析  

Fault Analysis of a 500 kV Capacitive Voltage Transformer

作　　者：于群英 赵春明 杨代勇 郭家昌 林海丹 邰宇峰 YU Qunying;ZHAO Chunming;YANG Daiyong;GUO Jiachang;LIN Haidan;TAI Yufeng(State Grid Jilin Electric Power Company Limited Electric Power Research Institute,Changchun 130021,China)

机构地区：[1]国网吉林省电力有限公司电力科学研究院,长春130021

出　　处：《吉林电力》2023年第5期35-36,40,共3页Jilin Electric Power

摘　　要：针对一起500kV电容式电压互感器(capacitive voltage transformer,CVT)故障进行分析诊断。首先,通过红外测温识别确认中节电容存在温差异常点;其次,对CVT进行介损和电容量测量试验,发现中节电容量与初厂值偏差9.32%,介质损耗为0.97%,超过规定值;最后,经过解体,确认内部第四、五组电容击穿损毁严重。得出结论:由于电容单元上部盖板密封胶圈破损,中节电容单元内部进水受潮,水汽在底部积聚,使得绝缘劣化放电,部分电容元件击穿。最后提出了预防CVT发生故障的措施。Analyze and diagnose a 500kV capacitive voltage transformer(CVT)fault.Firstly,the abnormal point of temperature difference in the middle section capacitor is confirmed by infrared temperature measurement identification.Then,the dielectric loss and capacitance measurement test of CVT were carried out.It was found that the initial value deviation of middle section capacitance was 9.32%,and the dielectric loss was 0.97%,exceeding the specified value.Finally,it was confirmed that the internal fourth and fifth groups of capacitors had serious breakdown and damage.This paper summarizes the fault development process that the sealing rubber ring of the upper cover plate of the capacitor unit is damaged,the water in the middle capacitor unit is affected by moisture,and the moisture accumulates at the bottom,resulting in insulation deterioration,discharge and breakdown of some capacitor elements.Finally,some suggestions on strengthening the sealing of equipment are put forward.

关 键 词：电容式电压互感器 电容单元 受潮 密封胶圈 

分 类 号：TM451[电气工程—电器]