投切电容器组产生重击穿及NSDD过电压对电容器影响分析

Analysis of the Influence of Overvoltage Caused by the Restrike of Switching Capacitor Bank and NSDD on Capacitor

针对真空断路器投切电容器组时发生的重击穿与NSDD所产生的过电压问题,通过对投切电容器组发生重击穿与NSDD典型波形分析,同时5年来真空断路器在投切电容器组的型式试验和老炼试验中发生的重击穿与NSDD次数统计,在中性点不接地系统中,NSDD发生次数远大于重击穿次数,发生重击穿与NSDD在电容器极间与真空断路器断口所产生的过电压基本是没有差异的。因此对NSDD的所产生对电容器的危害是不能忽略的。

Aiming at the problem of overvohage caused by the restrike of the vacuum circuit breaker switching capacitor bank and NSDD, through the analysis on the restrike caused by switching capacitor bank and NSDD typical waveform, at the same time, in the past 5 years, the breakdown and the NSDD number of the vacuum circuit breaker in the type test and burn-in test, in the neutral ungrounded system, the NSDD number is much larger than the restrike number, the restriking and NSDD, the overvohage between capacitor electrodes or breaks of vacuum breaker has no difference. Therefore, the harm of NSDD to the capacitor cannot be ignored.