FUZZY INTERFERENCE RELAY AND METHOD FOR CURRENT DIFFERENTIAL PROTECTION OF A TRANSMISSION LINE

摘要

A relay (100) for current differential protection of a transmission line, comprising: a first calculator (110) of symmetrical sequence components of currents of each phase of the transmission line at local and remote ends of the transmission line; a second calculator (110) of phase differences f12 and f012 between combinations currents i12 and i012 of the symmetrical sequence currents; a fuzzy inference system (112) which outputs a variable y whose value is calculated according to the values of the phase differences f12 and f012; a third calculator (120) which outputs a tripping signal for the control of a circuit breaker arranged on the transmission line and associated with the relay, the value of the tripping signal being calculated according to the values of the variable y and the values of the currents of each phase at the local and remote ends of the protected transmission line.