考虑不对称时延的线路电流差动保护拒动和误动概率分析  

Probability analysis on disoperation and misoperation of line current differential protection considering asymmetric delay

作　　者：张海生 彭玲艳 徐昊亮 徐慧慧 Zhang Haisheng;Peng Lingyan;Xu Haoliang;Xu Huihui(Economics&Technology Research Institute of State Grid Gansu Electric Power Company,Lanzhou 730050,China;School of Electrical and Electronic Engineering,North China Electric Power Uni/uersity,Baoding 071003,Hebei,China)

机构地区：[1]国网甘肃省电力公司经济技术研究院,兰州730050 [2]华北电力大学电气与电子工程学院,河北保定071003

出　　处：《电测与仪表》2021年第2期40-46,共7页Electrical Measurement & Instrumentation

基　　金：国网甘肃省电力公司委托开发项目(271833)。

摘　　要：通道时延不对称会影响线路电流差动保护的时间同步精度,并降低保护动作的可靠性。因此有必要对拒动和误动的影响机理进行深入研究,以提高线路保护的整体可靠性。文章根据线路电流差动保护的基本原理和时间同步方式,分析了通道不对称时延导致保护拒动和误动的原因;给出了通道不对称时延诱导的拒动和误动概率模型,并设计了相应算法;以5种线路保护场景作为算例,验证了算法的可行性和有效性,定量研究了在通道不对称时延概率分布函数相同条件下,拒动和误动概率的不同特征。研究成果对继电保护通道的优化配置和保护策略选择具有一定的参考价值。The asymmetry of channel delay will affect the time synchronization accuracy of line current differential protection and reduce the reliability of protection action.It is necessary to conduct an in-depth study on the mechanism of the impact of disoperation and misoperation to improve the overall reliability of line protection.Firstly,according to the basic principle of line current differential protection and time synchronization mode,the reasons of protection disoperation and misoperation caused by asymmetric channel delay were analyzed.Then,the probability models of disoperation and misoperation induced by asymmetric channel delay were given,and the corresponding algorithms were designed.Finally,five scenarios of line protection were taken as examples to verify the feasibility and effectiveness of the algorithm.The different characteristics of disopetation probability and misoperation probability under the same asymmetric channel delay probability distribution function were studied quantitatively.The research results have reference value for the optimal configuration and the selection of protection strategies of relay protection channels.

关 键 词：线路电流差动保护 不对称时延 拒动概率 误动概率 

分 类 号：TM7331[电气工程—电力系统及自动化]