Fault classification based on wavelet transforms

This paper presents a new approach to fault classification on transmission lines for high speed protective relaying. The scheme is based on the use of wavelet transform and implementation of digital signal processing concepts. It uses samples from the three line currents. The data window is 6 samples based on 10 kHz sampling rate. The new technique is tested on data simulated on EMTP for the 11 types of faults at different fault locations, different fault resistances, different fault inception angles, and different system parameters. The test results showed that the proposed algorithm offers a fast and secure technique for fault classification in power systems. The paper presents the basics of the wavelet transforms technique in power systems terminology and illustrates its use in the new algorithm.