内桥接线变电站主变差动速断保护误动分析

Analysis on Maloperation of Differential Quick Break Protection for Main Transformer of Inner Bridge Substation

内桥变电站减少了主变进线开关,在节约设备投资方面有显著成效。但因断路器和电流互感器配置方面的原因,高压侧差动回路由进线开关CT和桥开关CT构成。本文通过对一起主变差动速断保护误动案例进行分析,指出配置存在的问题,并提出改进措施。

The inner bridge substation reduces the main transformer inlet switch, and has remarkable effect in saving equipment investment. Because of the configuration of circuit breaker and current transformer, the differential return circuit of high voltage side is composed of CT and bridge switch CT. In this paper, through analysis of a case of maloperation of differential quick break protection of main transformer, the problems in configuration are pointed out and improvement measures are put forward.