6kV电机保护拒动引起机组跳闸事故中的保护分析

分析了一次高压电机速断保护拒动引起两台机组跳闸的事故,得到导致保护拒动的原因是电流互感器饱和,介绍了通过伏安特性试验确定其饱和特性的方法,提出了解决电流互感器饱和的措施.说明了事故中多台高压电机负序电流保护误动产生的原因,同时对高压电机负序电流保护动作时限整定进行了探讨,从保证机组安全运行的角度提出了整定原则.

Protection Analysis of Tripping Accidents Caused by 6kV Motor's Failure to Trip

Analysis was made to a two-machine-set tripping accident caused by a high-voltage motor's failure to trip at quick-breaking.The reason was that the current transformer saturation made motor protection not work.Introduction was made to a method making certain its saturation characteristics by means of testing the current-voltage characteristics,measures to avoid current transformer saturation set forth.This paper illustrated the reason why several high-voltage motors' negative sequence current protection was...