Fuzzy-logic-based high accurate fault classification of single and double-circuit power transmission lines

In this paper, a fuzzy logic-based fault classification of transmission lines is proposed. The classification procedure is carried out by only current phasors of three phases. The proposed technique is able to classify all the possible faults including single-phase to ground, two-phases, two-phases to ground and three-phases faults with high accuracy in a wide variety of system pre-fault loading conditions. In addition, this method can identify the faulted phase(s) from non-faulted phase(s). The mutual effect of parallel transmission lines has been investigated in this study, too. The proposed method has a good performance in high fault resistances, high system loading level and high fault distances from relaying point. Large numbers of test cases are generated to verify the performance of proposed technique. The simulation studies have been carried out by using PSCAD/EMTDC and MATLAB fuzzy-logic toolbox.