高阻接地故障双重化保护动作不一致原因分析

Cause analysis of duplicate protection action inconsistency for high-resistance grounding fault

针对220kV线路高阻接地故障过程中线路两侧双重化保护动作行为不一致的问题,依据故障时序分为3个阶段分析故障保护报文信息和录波,同时通过故障仿真计算验证,找出保护动作不一致的原因和影响保护动作行为的现场缺陷,提出保护定值整定方法及保护装置应用的优化逻辑,以使高压线路发生高阻接地时两侧双重化保护装置能够快速、一致的动作,最大限度地保护电网和设备安全。应用结果表明:提出的保护整定方法易于计算,适用于220kV及以上线路保护定值计算,利用背侧电源大小整定保护启动值从根本上解决了线路两侧保护动作不一致问题。

Aiming at the problem of duplicate protection action inconsistency on both sides of the line in the process of high-resistance grounding fault of 220 kV transmission line,according as fault time order divides three phases to analyze fault protection report information and fault waveform, simultaneously by fault simulation calculation and verification,finds out the causes of protection action inconsistency and protection action behavior defect,puts forward the setting method and optimization logic for application for protection device,when high-resistance grounding fault occurs on high voltage line,both sides of duplicate protection device can act fleetly and congruously, uttermostly protects the security of power grid and equipments. The application result shows that the proposed protection setting method calculate easy,suits for 220 kV and above line protection setting calculation,using dorsal power source value setting protection start-up value solves the problem of protection action inconsistency on both sides of transmission line.