计及系统不对称的谐振接地系统故障点残流测算方法  

A method of calculating residual current at fault points in resonant grounding system considering system asymmetry

作　　者：乔东伟 宫德锋 张帆[2] 杨坤 郭昱延 葛颂 薛永端[2] QIAO Dongwei;GONG Defeng;ZHANG Fan;YANG Kun;GUO Yuyan;GE Song;XUE Yongduan(Tai'an Power Supply Company of State Grid Shandong Electric Power Company,Tai'an 271000,China;College of New Energy,China University of Petroleum(East China),Qingdao 266580,China)

机构地区：[1]国网山东省电力公司泰安供电公司,山东泰安271000 [2]中国石油大学(华东)新能源学院,山东青岛266580

出　　处：《供用电》2024年第7期49-54,共6页Distribution & Utilization

基　　金：国家电网有限公司科技项目“基于接地故障信息的消弧线圈补偿状态在线评估”(520609220005)。

摘　　要：在谐振接地系统中,故障点残流的测算对于故障风险防范等运维工作具有指导意义。针对计及系统不对称的谐振接地系统单相接地故障,首先,分析了正常运行状态和接地故障运行状态的中性点电气量关系,分析表明故障点残流为故障前后的母线零序电压在系统零序总导纳上产生的电流差;然后,结合由逐差法计算得出的系统对地参数及母线零序电压等数据,提出一种故障点残流测算方法;最后,通过MATLAB/Simulink仿真验证,表明该方法基本不受过渡电阻的影响,且测算结果准确性较高。In the resonant grounding system,calculation of residual current of grounding point has guiding significance for prevention of fault risk and other maintenance works.Aiming at the single-phase grounding fault of the resonant grounding system considering the system asymmetry,this paper firstly analyzes the neutral point electrical quantity relation between normal operation state and grounding fault state.The analysis shows that the residual current of fault point is the current difference produced by the bus zero-sequence voltage before and after the fault on the total zero-sequence admittance of the system.Then according to the system grounding parameter calculated by successive difference method and bus zero-sequence voltage,a method of calculating the residual current of fault point is proposed.MATLAB/Simulink simulation show that the method is basically not affected by transition resistance,and it has higher calculation accuracy.

关 键 词：谐振接地系统 单相接地故障 系统不对称 故障点残流 逐差法 

分 类 号：TM73[电气工程—电力系统及自动化]