基于信号注入的谐振接地系统故障点残流测算方法  

A method for calculating residual current in a resonant grounding system based on signal injection

作　　者：张帆[1] 薛永端[1] 徐丙垠 ZHANG Fan;XUE Yongduan;XU Bingyin(College of New Energy,China University of Petroleum(East China),Qingdao 266580,China;Smart Grid Research Institute,College of Electrical and Electronic Engineering,Shandong University of Technology,Zibo 255000,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东青岛266580 [2]山东理工大学电气与电子工程学院智能电网研究院,山东淄博255000

出　　处：《电力系统保护与控制》2023年第13期132-138,共7页Power System Protection and Control

基　　金：国家自然科学基金项目资助(52077221)。

摘　　要：谐振接地系统中,故障点残流的测算对于故障风险防范、消弧线圈补偿效果评估等运维工作具有指导意义。然而,长期以来始终未找到合理的技术方向。针对谐振接地系统单相接地故障,首先分析正常状态下信号注入和接地故障燃弧状态下两个不同阶段线路出口处的零序测量导纳。分析表明,信号注入时所有线路的零序测量导纳为本线路导纳,而故障发生后故障线路的零序测量导纳为背后导纳。然后,根据零序测量导纳和母线零序电压,分别计算故障点残流中的有功分量和无功分量,进而提出一种故障点残流测算方法。Matlab/Simulink仿真验证表明,该方法基本不受系统失谐度和过渡电阻的影响,且测算结果准确性较高。In a resonant grounding system,calculation of the residual current of the grounding point has guiding significance for prevention of fault risk,the compensation effect evaluation of the arc suppression coil and other maintenance.However,a reasonable technical direction has not been found.Considering the single-phase grounding fault of the resonant grounding system,this paper analyzes the zero-sequence measured admittance at line outlets in the two different stages(normal state of signal injection and arc-ignition state of grounding fault).The analysis shows that the zero-sequence measured admittance at all line outlets when there is signal injection reflects the admittance of the line admittance.Those of the faulty line outlet when grounding fault occurrence reflect the back admittance.Then according to the two admittances and the bus zero-sequence voltage,the active and reactive components of residual current can be calculated.A method for calculating residual current is proposed.Matlab/Simulink simulation shows that the method is basically not affected by detuning degree and transition resistance,and has higher calculation accuracy.

关 键 词：谐振接地系统 单相接地故障 故障点残流 零序测量导纳 信号注入 

分 类 号：TM862[电气工程—高电压与绝缘技术]