Fault location for double-circuit transmission lines using travelling-wave theory with unsynchronized measurements

This paper describes a fault location method for double-circuit transmission lines using Travelling wave theory with unsynchronized measurements. Wavelet transform is used for analyzing power system fault transients in order to capture the travel time of the transients along the monitored lines between the fault points and relays. An analytical procedure is applied for synchronization of signals. The fault location is determined by taking time difference between arrival of the backward and forward travelling waves for synchronized measurements. The proposed method is mainly focused on locating symmetrical faults using synchronized measurement and is evaluated by comparing with recently developed approach [9]. Simulation results are carried out in MATLAB environment by considering different fault situations and results indicate how the limitations of existing method are overcome by the proposed method.