35kV 小电流系统异名相接地故障主变差动保护动作分析

Analysis of differential protection action of main transformer with synonymous phase grounding fault in 35kV small current system

摘要: 摘要：某日 03 时 19 分 34 秒，某 35kV 变电站 1 号主变差动保护动作，该站上一级 110kV 变电站 2 号主变中后备保护及 35kV 甲线保护启动未出口。现场检查乙站 35kV 分段 3101 隔离开关 C 相瓷瓶断裂掉落，1 号主变 302、310、011 断路器事故跳闸，1 号主变失压。

Abstract: Abstract: at 03:19:34 on a certain day, the differential protection of No. 1 Main Transformer in a 35KV substation acted, and the backup protection and 35kV line a protection in No. 2 main transformer in the upper 110kV substation of the station were started but not exported. On site inspection showed that the c-phase porcelain insulator of 3101 disconnector in 35kV section of station B broke and fell, the circuit breakers 302, 310 and 011 of No. 1 Main Transformer tripped accidentally, and No. 1 Main Transformer lost voltage.