Selections of transformer differential relay using fuzzy logic application / Mohd Shamsul Ibrahim

This final project studies the digital relay for the main protection of power transformer. This protective relay should avoid unnecessary trips according to some problems and several criteria of currents. They must block the tripping during the magnetizing inrush current and rapidly operate the tripping during internal fault current. The main objective of this study is to enhance the performance of digital relay by using a fuzzy logic application. The sensitivity and selectivity of the digital relay is analysed to overcome the problems associated with the conventional relay. The MATLAB 6.1 Fuzzy Logic Toolbox is used in order to achieve the performance of relay decision making. The results were compared with Electro-Magnetic Transient Program (EMTP) simulation and this technique is found to be of high sensitivity and speed during fault conditions.