Sparse S-transform for location of faults on transmission lines operating with unified power flow controller

This study presents a new fault location algorithm for a transmission line operating with a unified power flow controller (UPFC). The proposed algorithm is based on a new matrix version of the conventional S-transform called sparse S-transform (SST), using selected frequency components to increase the speed of the computation significantly. A variety of faults are initiated before and after the location of UPFC on the transmission line using MATLAB/SIMULINK platform. Further, the impedance trajectories and fault location are estimated using SST with significant accuracies. The computational speed of the SST is almost 30 times faster than the conventional discrete S-transform which makes it a suitable candidate for real-time application in digital relaying.