A New Method for Faulty Location in Distribution Systems Based on Wavelet Packet Decomposition and Signal Distance

摘要

Aiming at the fault characteristics of single-phase grounding system is not obvious and is susceptible to noise signals, a new method for single-phase ground fault segment location based on wavelet packet and signal distance is proposed. When a single-phase ground fault occurs in the resonant grounding system, the wavelet packet is used to perform multi-layer decomposition of the zero-sequence current after the fault, and after removing the lowest frequency band where the power frequency is located, the wavelet packet decomposition coefficients of each layer are extracted and processed by the signal distance algorithm to form A segment location vector that filters the largest element in the vector to determine the faulty segment. Theoretical analysis and simulation results show that the method is not affected by fault conditions such as transition resistance and fault initial phase angle, and can accurately realize the positioning of small current single-phase ground fault sections.