基于HFCT局放测试技术的高压电缆终端失效检测方法研究

Research on failure detection method of high voltage cable terminal based on HFCT test technology of partial discharge

针对高压电缆终端因缺陷造成的运行失效问题,分析局部放电的机理,采用HFCT(高频电流传感器)的局放测试技术并结合交流变频谐振耐压的试验方式,设计了一种通过监测电缆终端在不同试验电压下的局部放电图谱,以确定电缆终端发生失效状态的检测方法。通过现场化的试验验证,有效地发现了高压电缆终端缺陷。应用该检测方法,解决了高压电缆工程竣工验收问题,可以在电缆终端竣工验收中有效地发现微小缺陷,对于提前判断高压电缆终端失效具有明显效果。可避免因终端失效造成的电缆运行故障甚至是终端头爆炸等事故。

In view of the high voltage cable terminal operation failure caused by defects, this paper analyzes the mech- anism of partial discharge, with the combination of AC variable frequency resonant pressure test by using the partial discharge test technology of HFCT （ high frequency current sensor） , and designs a method to determine cable termi- nation happen failure state detect by monitoring partial discharge pattern of cable termination under different test volt- age. Through the field test, the terminal defect of high voltage cable is found effectively. The problem of high voltage cable project completion acceptance is solved through the application of the test methods, which can be effectively found in cable terminal completion inspection and acceptance imperfections, and have obvious effect on judging high voltage cable terminal failure in advance. It can avoid the failure caused by cable terminal malfunction even terminal head explosion accidents.