Diqing Power Supply Bureau of Yunnan Power Grid Co, Ltd.,
In order to solve the problem that it is difficult to locate the fault section when single-phase to ground fault occurs in small current grounding system of distribution network, this paper proposes a fault section location method based on Hausdorff dist algorithm combining with the characteristics that the zero sequence currents on both sides of the fault point are opposite in the fault line. In this method, the zero sequence current is regarded as the fault feature. Firstly, the zero sequence current is filtered, and then the wavelet approximate sequence of the zero sequence current of each detection node of the fault feeder is extracted by wavelet packet transform. Then, the deviation matrix of the wavelet approximate sequence of the zero sequence current between each detection node is obtained by using Hausdorff dist algorithm. Finally, a deviation degree is defined to represent the difference between the two sides of each section The fault section is determined by comparing the deviation degree. The simulation results show that the method can achieve correct positioning under different fault conditions, and it is also suitable for complex distribution network structure, which is convenient for distribution network operators to quickly repair and maintain the fault lines, and ensure the safe and reliable operation of power system.