State estimation based transmission line fault locating with sequence distributed parameter models

This paper presents a novel phasor-domain dual-ended transmission line fault locating method enabled by sequence distributed parameter models and the state estimation algorithm. The method only requires fundamental frequency phasor measurements. Best implementation requires GPS synchronization at both terminals of the line. The method first models the transmission line with fault in sequence domain with distributed parameters, to accurately consider the effect of charging currents. Second, the state estimation algorithm is adopted to make full use of the redundancy in the fault locating problem and to cross check the estimated fault location. Numerical experiments demonstrate that the method has better accuracy than legacy fault locating methods, independent of fault types, locations and impedances.