A NEW MICROCOMPUTER-BASED APPROACH FOR PILOT DIFFERENTIAL PROTECTION OF TRANSMISSION LINES

Abstract--This paper presents a theoretical nd experimental study of a new technique for pilot differential protection of transmission lines. The difference currents obtained from post- and pre-fault line currents, adjusted by calculated charging currents, are used to minimize the desensitizing effect of load and line charging currents. The experimental results are from a laboratory 16-bit microcomputer-based relay that was developed to test some of the features of this new approach. Off-line test results for various types of faults on a lumped parameter long transmission li e model and real-time test results for a short transmission li e model are presented