A New Fault Location Algorithm for Use With Current Differential Protective Relays of Series Compensated Transmission Lines

An algorithm for locating faults on series-compensated transmission lines is presented. Use of two-end synchronized measurements of currents accomplished by current differential protective relays with additional incorporation of the locally measured three-phase voltage is considered. In case of double-circuit lines also providing of zero-sequence currents from the healthy parallel line is assumed. More superior solution with the fault location function embedded into the differential relays at both line ends is considered. The algorithm applies two subroutines designated for locating faults on line sections at both sides of the capacitor bank. Additionally the procedure for selecting the valid subroutine is applied. The developed algorithm has been tested and evaluated using signals taken from ATP-EMTP versatile simulations of faults on a test transmission line. The presented sample results of the testing show the validity of the presented fault location algorithm and its high accuracy.