基于零序特征参量差异的谐振接地系统熄弧时刻判别方法  

Arc-extinction Time Judgement of Resonant Grounding System Based on Difference of Zero-sequence Characteristic Parameter

作　　者：张帆[1] 薛永端[1] 仉志华[1] 乔东伟 徐丙垠[3] ZHANG Fan;XUE Yongduan;ZHANG Zhihua;QIAO Dongwei;XU Bingyin(College of New Energy,China University of Petroleum(East China),Qingdao 266580,Shandong Province,China;Tai’an Power Supply Company of State Grid Shandong Electric Power Company,Tai’an 271000,Shandong Province,China;Smart Grid Research Institute(Shandong University of Technology),Zibo 255000,Shandong Province,China)

机构地区：[1]中国石油大学(华东)新能源学院,山东省青岛市266580 [2]国网山东省电力公司泰安供电公司,山东省泰安市271000 [3]智能电网研究院(山东理工大学),山东省淄博市255000

出　　处：《电网技术》2024年第1期343-351,共9页Power System Technology

基　　金：国家自然科学基金项目(52077221)。

摘　　要：在谐振接地系统中,熄弧时刻的准确判别对于接地故障的选线、消弧效果评估以及熄弧后暂态信息提取和利用具有指导意义。该文针对谐振接地系统单相接地故障,分析了故障点工频电流熄弧前后的故障电气特征,并利用母线零序电压和消弧线圈电流,通过求取其信号的一阶导数及其平方信号的二阶导数,构造两种特征参量。研究发现该特征参量在熄弧前为常数,熄弧后发生明显变化,据此可形成相应的熄弧时刻判别的基本判据。考虑到系统实际运行中各种因素的影响,在此基础上形成熄弧时刻判别的附加判据,从而最终提出基于零序特征参量差异的谐振接地系统熄弧时刻判别方法。通过Mat Lab/Simulink仿真和现场实测,验证了该熄弧时刻判别方法的有效性和准确性。In the resonant grounding system,the accurate judgement of the arc-extinction time has a guiding significance for the line selection of a grounding fault,the evaluation of the arc suppression effect,and the extraction and utilization of the transient information after an arc extinction.Aiming at the single-phase grounding fault of the resonant grounding system,this paper analyzes the electrical characteristics of the fault before and after an arc extinction.By using the bus zero-sequence voltage and the Petersen's coil current,the two characteristic parameters are constructed by obtaining the 1st-order derivative of its signal and the second-order derivative of its squared signal.It is found that the characteristic parameters are constant before the arc extinction,while change significantly after the arc extinction,which can be utilized to form the corresponding basic criterion for the arc extinction time.Considering the influences of various factors in the actual operation of the system,an additional criterion for the arc extinction time are given,and finally a method for judging the arc-extinction time of the resonant grounding system based on the difference of electrical characteristics is proposed.The validity and accuracy of the method for judging the arc-extinction time are verified through the MatLab/Simulink simulation and a field test.

关 键 词：谐振接地系统 接地故障 特征参量 熄弧时刻 

分 类 号：TM721[电气工程—电力系统及自动化]