一起35kV变电站10kV站变跳闸分析

Analysis of a 10kV Substation Transformer Trip in a 35kV Substation

针对广东某35 kV变电站相邻35 kV线路故障跳闸时导致站变低压零序保护动作跳闸,跳开站变两侧开关,并闭锁ATS,导致站用电系统失压的问题,经过分析后得知是由于站变低压侧零序TA安装位置不合适,导致当产生不平衡电流时低压零序保护动作造成的,提出了站变低压零序TA安装位置的改进方法,解决了站变低压零序保护误动造成站用交流电失压事件的问题。

When the 35 kV line of a 35 kV Substation in Guangdong triped due to fault, the low-voltage zero sequence protection of the substation transformer acted. The breakers on both sides of the substation transformer tripped and the ATS was locked. The substation power system was lost. Through analysis, it was caused by improper installation position of zero sequence TA at low voltage side of the substation transformer. This paper presents an improved method for the installation position of the substation transformer low voltage zero sequence TA, which solves the problem of incorrect action of station transformer low voltage zero sequence protection.