Optimized wavelet transform based fault ranging of transmission line in substation

Abstract

To address the issue of insufficient positioning accuracy caused by faults in the transmission lines between substations, this study established a single-terminal travelling wave ranging model and proposed an optimized wavelet transform-based method for processing travelling wave signals. Using MATLAB as the simulation platform, we conducted simulations of single-terminal travelling wave ranging. The critical challenge in this method lies in accurately identifying the arrival time of the travelling wave signals. To address this, two different wavelet basis functions were selected to process the travelling wave signals, and their effectiveness in processing the same fault at different locations was compared and analyzed. The results show that the db4 wavelet better retains the original signal features. The error range for the Haar wavelet was 0.4289–0.6948 km, while for the db4 wavelet it was 0.0301–0.2960 km. Thus, the db4 wavelet provides more accurate ranging than the Haar wavelet.