Fault Zone Location Scheme Based on DTW Distance for Distribution Networks

For the small current grounding system, to quickly and effectively identify and isolate the faulted section, this paper proposes to use the characteristics of the fault transient zero-mode current to form the idea of locating the faulted section based on the phase difference of the waveform of the main resonant frequency of the zero-sequence current. The transient zero-mode current within 10ms after the fault of each line is filtered by using a filter, and the main resonance frequency waveform(MRFW) is accurately extracted by the VMD, after the normalization process, in the same cycle, the DTW distances between the neighboring monitoring points are computed in turn, and compare the DTW distance values of MRFWs on both sides of the region with the size of the threshold as a judgment condition. The fault zone location scheme of the distribution network using the phase difference of the main resonant frequency waveform is designed. A large number of single-phase ground fault scenarios are simulated using MATLAB modelling, and the results show that: the main resonant frequency waveforms upstream and downstream of the fault on the faulty line have obvious differences. The faulty zone DTW distance value is larger than the threshold, and the sound zone DTW distance value is smaller than the threshold, i.e., it shows that the scheme can reliably and correctly find the faulty zone, and it has a certain value for engineering applications.