DETECTION OF HIGH-IMPEDANCE FAULTS IN TRANSMISSION LINES USING WAVELET TRANSFORM

A novel approach for detection of High Impedance Faults (HIF) using wavelet transforms is presented in this work. Wavelet functions have been proposed in connection with the analysis of signals, primarily transients in a wide range of applications. The technique used here, is based on using the absolute sum value of coefficients in Multi resolution Signal Decomposition (MSD) based on the Discrete Wavelet Transform (DWT). A fault indicator and a fault criterion are then used to detect the HIF in the transmission line. The technique developed is robust to fault type, fault inception angle, fault resistance, and fault location. A new concept and methodology for HIF in transmission lines is presented. The performance of the proposed technique is tested under a variety of fault conditions on a typical 400KV transmission-line system.