High impedance fault detection based on power spectrum technique

Abstract

High Impedance Fault (HIF) is irregular event in feeder which makes the current too much less than common current in network and cannot be detected via standard protective devices. The protection system in the feeder suited only for the faults have high current more than 1000A and the current caused by HIF is very little about 50A cannot be sensed by the general protection strategies. This causes hazard to the Human and environment like shocking and firing. The signals of HIF and other usual cases on feeder like Capacitor Bank (CB), Nonlinear Load (NL) and Linear Load (LL) have same waveform. So, this paper used new technique can recognize HIF from any likely cases on feeder with high accuracy and less time than other method. The Fast Fourier Transform (FFT) is used for decomposition and extracts the signals of HIF and other power system incidents. The signals data of HIF, CB, NL and others usual cases which have same waveform simulated with 13.8KV on distribution system by using MATLAB/Simulink. The signals data extracted by FFT after the simulation applied to Power Spectrum (PS) technique which can detect HIF and recognize it from any standard cases on feeder with 100% accuracy.