HIF analysis using discrete wavelet transform

Abstract

A high-impedance fault (HIF) is generated when an overhead power line physically breaks and falls to the ground or when makes unwanted contact with any object to ground which restricts the flow of current. Such kind of fault are difficult to detect and locate in electric distribution systems because of the small currents magnitudes involved which cannot be detected by conventional overcurrent protection. Furthermore, an arcing often accompanies high-impedance faults that can result in fire hazard, damage to electrical equipment, or even worst, a risk to human life. For these reasons the high impedance faults phenomenon has been the subject of intense research. In this paper an analysis HIF field test using the discrete wavelet transform (DWT) is presented, the proposed analysis is a step forward in the HIFs detection and localization in electric distribution systems.