A fault classification scheme with high robustness for transmission lines using fuzzy-logic system

This paper present a new and accurate scheme for fault classification of EHV transmission lines using fuzzy logic system. The fault classification scheme is developed by using only the post-fault magnitude of three phases current and its symmetrical components. The proposed fault classification technique is able to classify all faults type can be affect a transmission line such as the single-phase to ground faults, two-phases faults, two-phases to ground faults and three-phases faults with high accuracy under wide variety of fault conditions. The proposed scheme has a good performance in high fault conditions such as high fault resistances, high fault inception angles and high fault distances to fault from relaying point. Large numbers of test cases are generated to verify the performance of proposed scheme. The simulation studies have been carried out by using Matlab software and Matlab fuzzy-logic toolbox.