基于相电压电流突变量的配电网单相接地故障频域定位方法

Frequency Domain Location Method for Single-phase Grounding Fault of Distribution Network Based on Break Variable of Phase Voltage and Current

为了克服配电网单相接地故障时域定位方法需要设计专门的滤波器以及解决零序电压电流较难获取的问题,提出了一种基于相电压电流突变量的频域定位算法。首先给出了配电网单相接地故障的突变量网络并分析了相电压电流突变量特征。在此基础上构建了频域模型方程并提出了对地电容的辨识方法,对于健全线路和故障线路故障点后各相以及故障点前健全相的对地电容值为正,故障点前故障相的对地电容值为负,据此可以实现单相接地故障的区段定位以及故障相识别。最后提出了定位终端的启动方法和实用化判据,将算法写入某终端并基于RTDS进行了测试,结果证明所提方法的有效性。

In order to overcome the shortcomings that the time-domain fault location method of single-phase grounded fault in distribution network needs filtering and the zero-sequence voltage and current are difficult to obtain,a frequency domain fault location algorithm based on break variables of phase voltage and current is proposed in this paper.Firstly, the mutation network of single-phase grounding fault of distribution network is given and the characteristics of break variables of phase voltage and current are analyzed.Based on this,the frequency domain model equation is built and the identification method of the capacitance is given.The capacitance of each phase of sound line and downstream segments of fault point as well as sound phases of upstream segments of fault point is positive.The capacitance of faulty line of upstream segments of fault point is negative.According to this,fault segment location and fault phase identification can be realized.Finally,the starting method and practical criteria of the positioning terminal are given.The algorithm is written into a terminal and tested based on RTDS.The test result verifies the effectiveness of the proposed method.