摘要
介绍了一起区外故障引起的主变差动保护动作分析处理过程。通过对现场相关电气设备、回路进行了特性试验、绝缘检查、回路测量,对动作报告和录波进行了分析,确定原因是变压器中压侧B相区外发生接地故障,同时C相区内发生瞬时性绝缘击穿,诱发接地故障,B、C相通过过渡电阻(大地)发生转换性B、C相间短路,从而导致差动保护跳闸。
This paper describes analysis process of the main transformer’s differential relay operation caused by an external fault. Through related on-site electrical equipment examining, circuit characteristics tests, insulation inspection, circuit measurement and analysis of the action report and recorded wave, it is confirmed that the transformer’s B-phase in external midium-voltage side occurred earth fault, at the same time, C-phase occurred internal earth fault because of insulation breakdown. So B, C phase through the transition resistance （earth） occur phase fault, which led to differential protection tripping.
出处
《电力系统保护与控制》
EI
CSCD
北大核心
2010年第4期134-136,139,共4页
Power System Protection and Control
关键词
差动保护
接地故障
differential relay
earth fault
