A NEW PHASOR MEASUREMENT BASED FAULT LOCATION ALGORITHM FOR TRANSMISSION LINES

A new phasor measurement based adaptive fault location algorithm which is available to single circuit transmission line and the double circuit transmission lines on same tower is presented. To locate the fault, in this algorithm the current and voltage phasors at the two ends of transmission line and the lumped parameter model are adopted in the on-line calculation of positive sequence parameters of the P-type of equivalent circuit model of transmission line, and the non-determinacy problem of the line parameters during the operation is solved. To implement the two terminals fault location the mutation quantities before and after the fault are acquired from the data sampled at both ends of the transmission line, the equivalent system impedances for single circuit transmission line and double circuit transmission lines on same tower, which are applied to the fault location, are calculated by the symmetrical components and the six sequence components respectively. A lot of simulation results by EMTP and the testing data from practical power systems show that the presented algorithm possesses high fault location accuracy, this algorithm can adapt the changes of power system operating modes and is not affected by the transition resistance at the faulty position, the fault modes and the distance to the faulty point.