基于广域零序电流分布特征的非调度端配电网单相接地选线方法

A Single-phase Grounding Line Selection Method for Distribution Network of Non-dispatching Terminal Based on Distribution Characteristics of Wide-area Zero Sequence Current

针对小电流接地系统接地选线装置成本高、停电范围广、准确性低等问题,提出一种基于广域零序电流分布特征的非调度端配电网单相接地选线方法。该方法针对配电网单相接地故障,分析变电站母线三相电压的特征及线路零序电流的分布情况,引入接地判别算子及均值突变比较算子,依据选线策略进行概率排序进而分析出故障线路。最后,通过两个实际案例及运行数据统计分析论证:本文提出的单相接地选线方法可以精准识别故障线路及支线、快速定位故障范围,具有较高的准确性及鲁棒性。

Aiming at the problems of high cost,wide power outage range and low accuracy of grounding line selection devices in small current grounding system,a single-phase grounding line selection method for distribution network of non-dispatching terminal based on the distribution characteristics of wide-area zero sequence current is proposed.The method analyzes the characteristics of the three-phase voltage of substation busbar and the distribution of zero sequence current for single-phase grounding faults in distribution network.A grounding discrimination operator and a mean mutation comparison operator are introduced.The faulty line is identified by carrying out probability sorting according to the line selection strategy.Finally,through two practical cases and statistical analysis of operational data,it is demonstrated that the single-phase grounding line selection method proposed in this paper can accurately identify faulty lines and branches,quickly locate the fault range,and has high accuracy and robustness.