一起主变低压绝缘降低引起差动动作故障分析  

Analysis of one Differential Protection Action Caused by Low Voltage Insulation ofMain Transformer Decreasing

作　　者：陈浩 章桢 CHEN Hao;ZHANG Zhen(Changzhou Power Supply Branch,State Grid Jiangsu Electric Power Co.,Ltd.,Jiangsu Changzhou 213000,China)

机构地区：[1]国网江苏省电力有限公司常州供电分公司,江苏常州213000

出　　处：《农村电气化》2022年第2期32-33,共2页Rural Electrification

摘　　要：随着电网规模不断增长,设备运行年限增加,部分设备因运行环境、绝缘处理不当存在绝缘薄弱环节。分析了一起主变低压绝缘降低引起差动动作故障,通过对保护动作情况、故障录波波形和设备检查情况,论证了设备故障原因,对故障中电容器低电压保护动作异常进行了简要分析,提出了事故防范措施。Some equipments insulation have low points because of the operation environment and service life with the developing of power system.This paper analyzes one differential protection action caused by low voltage insulation of main transformer decreasing.The B phase ground fault of 129 line in 10 kV II bus caused the A,C phrases voltage increasing.The insulation between the back of 102 breaker and the main transformer decreasing caused the three phase short circuit.Then the 2#main transformer differential protection acted.This confirmed that the insulation of the connecting and cutting row back of 102 breaker was weak.The main transformer ground point is not suitable in the connecting and cutting row back of breakers.

关 键 词：主变 绝缘差动保护 低电压保护 

分 类 号：TM77[电气工程—电力系统及自动化]