基于消弧线圈调制信号相关检测的高阻单相接地选线  

High resistance single-phase grounding line selection in resonant grounding systems based on correlation detection

作　　者：刘健 陈曦子 张志华 李瑞桂[3] LIU Jian;CHEN Xizi;ZHANG Zhihua;LI Ruigui(State Grid Shaanxi Electric Power Research Institute,Xi'an 710100,China;School of Automation,Xi'an University of Technology,Xi'an 710048,China;Hebei Xuhui Electric Co.,Ltd.,Shijiazhuang 050035,China)

机构地区：[1]国网陕西省电力有限公司电力科学研究院,陕西西安710100 [2]西安理工大学自动化学院,陕西西安710048 [3]河北旭辉电气股份有限公司,河北石家庄050035

出　　处：《电力系统保护与控制》2023年第1期63-70,共8页Power System Protection and Control

基　　金：国家自然科学基金重点支持项目资助“城市智能配电网保护与自愈控制关键技术”(U1766208);国家电网公司总部科技项目资助(5226SX22001C)。

摘　　要：为了提高谐振接地系统单相接地选线的抗过渡电阻能力,提出一种基于相关检测的单相接地选线方法。采用低频方波对消弧线圈补偿电流进行调制,分析故障线路与健全线路调制后的信号特征。将各条线路零序电流分别除以零序电压包络幅值加以调整后进行解调和相关检测。构造了基于互相关函数的单相接地选线判据,讨论了低频调制方波频率的选择对选线效果的影响。结合实例对所提出的方法进行了仿真和实验研究,结果表明所提方法在单相接地选线方面具有非常高的抗过渡电阻能力。To improve the level of limitation of high resistance single-phase grounding line selection in resonant grounding systems,a single-phase grounding line selection approach based on correlation detection is proposed.The compensation current of an arc suppression coil is modulated with a low-frequency square wave.The signal characteristics of fault and healthy lines after modulation are analyzed.The zero-sequence current of each line divided by the amplitude of zero sequence voltage enveloping is used for demodulation and correlation detection.A single-phase grounding line selection criterion based on a cross-correlation function is constructed and the influence of the selection of low-frequency modulated square wave frequency on line selection effect is analyzed and discussed.Simulation and experiments are carried out,the results of which show that it can accurately select the single-phase grounding line with a large high grounding resistance.

关 键 词：配电网 谐振接地系统 单相接地 单相接地选线 相关检测 互相关函数 

分 类 号：TM862[电气工程—高电压与绝缘技术]