A Novel Fault-Detection Technique of HIF in Distribution Network

This paper describes a novel fault-detection technique of high-impedance faults (HIFs) in Distribution Network using the wavelet transform. Such faults are the most difficult to detect in Electrical Distribution Systems and often draw small currents which cannot be detected by conventional protection. The technique is based on using the absolute sum value of coefficients in multiresolution signal decomposition (MSD) based on the discrete wavelet transform (DWT). In order to discriminate between HIF and nonfault transient phenomena, such as capacitor and line switching and arc furnace loads, the concept of duration time (i.e., the transient time period), is presented. On the basis of extensive investigations, optimal mother wavelets for the detection of HIF are chosen. It is shown that the technique developed is robust to fault type, fault inception angle, fault resistance, and fault location. The performance of the proposed technique is tested under a variety of fault conditions.

Keywords:

distribution network , Fault detection , high-impedance arcing fault , wavelet transform