An Improved Phasor Domain Parameter-Free Fault Location Algorithm on Untransposed Lines

This paper proposes a parameter-free fault location algorithm on untransposed transmission lines. Synchrophasor voltage and current measurements at both terminals of the line before and during faults are typically required. The method first builds the transmission line models before and during the fault, which describe all the physical laws that the line should obey. The fault location as well as transmission line parameters are introduced as unknown variables in the models. Afterwards, the fault location is obtained by accurately solving the unknown variables in the models. Compared to the existing parameter-free fault location methods on untransposed lines, the proposed method fully considers the lumped shunt capacitance matrix and directly solves the fault location without further assumptions. Numerical experiments in PSCAD/EMTDC proved that the proposed algorithm is more accurate than the existing untransposed parameter-free fault location method, independent of fault locations, fault types and fault impedances.