A protection technique for series capacitor compensated 400 kV double circuit transmission line based on wavelet transform including inter-circuit and cross-country faults

Abstract

In this paper, wavelet transform based technique is introduced to detect and classify the faults in a series capacitor compensated double circuit transmission line. The three phase currents of both circuits measured at only one end of the series compensated double circuit transmission line are used to calculate the approximate and high frequency detail coefficients including wavelet energy content of each phase current signal. To evaluate the performance of proposed fault detection technique, simulation studies have been carried out on a series capacitor compensated double circuit transmission line test system. The major advantage of this proposed scheme is that it offers protection to entire transmission line length using one end fault current data only. The test results prove that all types of faults are correctly detected and the faulty phase is accurately identified using proposed technique. This technique is robust to the variation in fault type, fault inception time, fault resistance, ground resistance and fault location. Keywords: Fault detection, fault classification, series capacitor compensated double circuit transmission line, wavelet transform