一起220 kV变电站N600一点接地电流过大缺陷分析及处理

Analysis and Treatment of a Defect of Excessive Grounding Current at N600 One-Point in 220 kV Substation

《电力系统继电保护及安全自动装置反事故措施要点》规定:经控制室零相小母线(N600)连通的几组电压互感器二次回路,只应在控制室将N600一点接地,各电压互感器二次中性点在开关场接地点应断开。文章对220 kV某站N600一点接地电流过大的缺陷进行处理,并提出相应改进措施。

"Key Points of Anti-accident Measures for Power System Relay Protection and Safety Automatic Devices"stipulates that several groups of secondary circuits of voltage transformers connected by zero-phase miniature bus(N600)in the control room should only have N600 one-point grounding in the control room,and the secondary neutral point of each voltage transformer should be disconnected at the grounding point of the switching field.This paper deals with the defect of excessive one-point grounding current at N600 of a 220 kV Station and proposes corresponding improvement measures.