电容式电压互感器油箱过热故障分析

电容式电压互感器虽与电磁式相比有许多优点,如不会与外部元件发生铁磁谐振、结构简单、绝缘裕度大等,但故障率也较高,较为常见的有电容器受潮、部分电容击穿等故障,而中间电磁单元由于种种原因产生故障致使油箱过热的事件也时有发生。笔者对几起油箱过热事件的过程及原因进行了介绍和分析,指出CVT油箱过热是由于电磁单元内部或外部故障使补偿电抗器保护电阻或阻尼电阻长期通流发热所致。

Analysis of CVT's Oil Tank Overheating Faults

Comparing with PT,CVT has many merits.For example,CVT doesn't occur ferromagnetic resonance with external elements,has simple structure and enough insulation excess,but CVT's faults ratio is still high.Capacitors damped and ca- pacitor cake breakdown are familiar faults of CVT.But affairs of the oil tank overheating often occur because of middle elec- tromagnetic units various faults.The paper introduced and analyzed the process and reasons of some fuel tank overheating in- cidents,and point out that,the overheating of the protection resistance and damping resistance by long-term earring current, which caused by internal and external faults of the electromagnetic units,are the main reason of the oil tank overheating.