配电网单相接地故障时的对地参数实时测量和选线方法  

Real-time Measurement of Ground Parameters and Line Selection for Single-phase Grounding Faults of Distribution Network

作　　者：王志成 宋国兵[1] 常仲学 雷智荣 党长富 魏志峰 刘海阳 WANG Zhicheng;SONG Guobing;CHANG Zhongxue;LEI Zhirong;DANG Changfu;WEI Zhifeng;LIU Haiyang(School of Electrical Engineering,Xi’an Jiaotong University,Xi’an 710049,Shaanxi Province,China;Xi’an Xirui Control Technology Co.,Ltd.,Xi’an 710077,Shaanxi Province,China;Beijing SGITG Accenture Information Technology Center Co.,Ltd.,Haidian District,Beijing 100052,China)

机构地区：[1]西安交通大学电气工程学院,陕西省西安市710049 [2]西安西瑞控制技术股份有限公司,陕西省西安市710077 [3]北京国网信通埃森哲信息技术有限公司,北京市海淀区100052

出　　处：《电网技术》2023年第9期3762-3769,共8页Power System Technology

基　　金：国家自然科学基金国际合作研究项目“NSFC-UKRI_EPSRC项目(中英)”(52061635105)。

摘　　要：配电网正常运行时测量的对地参数可能因运行方式的变化导致单相接地故障后有源电流方案消弧效果欠佳。针对以上问题,提出了一种配电网对地参数实时测量方法,在检测到配电网发生单相接地故障后,利用有源消弧装置注入特征频率电流信号,测量中性点电压与各线路零序电流,提取其中特征频率分量并通过最小二乘拟合算法计算系统过渡电阻和总对地电容。此外,通过测量各线路对地电阻值可实现故障选线。PSCAD的仿真结果和真型试验场实验结果证明了所提方案在不同故障场景下均能够实时准确测量配电网对地参数,也可实现故障准确选线。The ground parameters measured in the normal operation of a distribution network may lead to a poor arc suppression effect of the active current scheme after a single-phase grounding fault due to the change of the operation mode.In view of the above problems,this paper proposes a method of the real-time measurement for the ground parameters of the distribution network.After the single-phase grounding fault of the distribution network is detected,the active arc-suppression device is used to inject the characteristic frequency current signal.By measuring the neutral point voltage and the zero-sequence currents of the lines,the characteristic frequency component is extracted,and the system transition resistance and the total ground capacitance are calculated by the least squares fitting algorithm.In addition,the fault line selection can be realized by measuring the ground resistance of each of the lines.The simulation results on the PSCAD and the experimental results of the testing institution prove that the proposed scheme is able to accurately measure the ground parameters of the distribution network in real time under different fault conditions,and also achieve accurate fault line selection.

关 键 词：配电网 单相接地故障 线路压降 对地参数实时测量 选线 

分 类 号：TM721[电气工程—电力系统及自动化]