运行中发生电容器组熔断器全爆的故障分析

Fault Analysis of External Fuse Group Blowing in Capacitor Banks

从市区某变电站发生一起运行中的35 kV电容器组外熔断器群爆入手,根据现场该电容器组外熔断器全部熔断的事实,分析了故障发生时保护装置动作的波形图、故障后的电气试验结果和电容器现场安装情况,从电容器组和外熔断器安装的角度分析了导致外熔断器全部熔断的暂态过电压产生原因,最后得出电容器组及熔断器安装不当,在特殊情况下有可能发生暂态过电压导致熔断器群爆的结论。

This paper describes the fault, external fuse group blowing in an operating 35 kV capacitor banks, occurred at certain substation of urban area. According to the facts that all the external fuses were blown, the digital waveform replayed from the fault protection system, the electrical test results and the field installation of the capacitor banks in the fault are analyzed. The cause of transient over - voltage leading to complete fusing of external fuse is analyzed from the point of view of the installation of the capacitor bank and external fuse. And the final conclusion is made that inappropriate installation between the capacitor banks and the external fuses would , in case of special condition, induce fuse group blowing due to by over-voltage.