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

Due to the complexity of fault states and the low accuracy for line selection in a resonant grounding system, a novel line selecting method for single-phase grounding fault in distribution network based on wavelet packet decomposition and signal distance is proposed in this paper. With a single-phase grounding fault occurring in this system, the transient zero sequence current is decomposed into multiple layers by wavelet packet. The high frequency band decomposition coefficients are extracted and processed by signal distance algorithm. Then a distance matrix can be obtained to select the faulty line. The results of simulation show that this method can give an accurate selection of the faulty line without the effects of initial phase angle, fault location, transition resistance as well as compensation states of arc suppression coil.