一起线路跳闸引起35kV变电站失压的故障分析

Fault Analysis for Voltage-loss in 35kV Substation due to Line Tripping

针对雷击过电压引起35 kV架空线路绝缘子闪络,导致L1、L2相间接地短路、35 kV变电站全站失压及其电缆损坏的状况进行调查和分析,说明故障前电力系统的运行方式与35 kV南红线保护装置动作行为正确的同时,分析导致线路跳闸与电缆井电缆损坏的故障原因;针对35 kV及以上容易遭受雷电过电压影响引起跳闸的输电线路及红岭变电站一次接线现状,提出一系列针对性的整改措施,从而可大大提高变电站供电可靠性及其设备的安全性。

This paper investigates and analyzes faults of L1 and L2 phase grounding short-circuit, voltage-loss in one 35 kV substation and damages of cables on account of lightning over-voltage causing insulator flashover on 35 kV overhead lines. It expounds that both operation mode of the power system and protection devices of 35 kV Nanhong line are in correct operation, meanwhile, it analyzes reasons for causing line tripping and cable damages. In allusion to problems of 35 kV and the above power transmission line tripping caused by lightning over-voltage and status quo of the primary connection in Hongling substation, a series pointed rectification rrr.asures are proposed to greatly improve power supply reliability and security of equipment.