Detection of Transmission Line Faults by Wavelet Based Transient Extraction

In this paper, a novel technique is applied to detect fault in the transmission line using wavelet transform. Three phase currents are monitored at both ends of the transmission line using global positioning system synchronizing clock. Wavelet transform, which is very fast and sensitive to noise, is used to extract transients in the line currents for fault detection. Fault index is calculated based on the sum of local and remote end detail coefficients and compared with threshold value to detect the fault. Proposed technique is tested for various faults and fault inception angles. Simulation results are presented showing the selection of proper threshold value for fault detection.