FAULT LOCATION ALGORITHM FOR HIGH VOLTAGE TRANSMISSION LINE BASED ON DISTRIBUTED PARAMETER

Fault location for transmission lines is an imperative problem to be solved in electric power system. Fast and accurate location of the fault on the high voltage transmission line plays an increasingly important role. The conventional single terminal method of fault location can not eliminate the influence of the fault resistance and the remote in feed. The double terminal fault location algorithm based on line model equivalent using lumped parameters neglects the shunt capacitance in the line model, but for long distance transmission lines the shunt capacitance is essential for the design of a fault location algorithm. Considering the effect of line shunt capacitance, a fault location algorithm based on distributed parameter is presented, which only needs the line parameters and synchronized samples from both terminals. To eliminate the effect of untransposed conductors and unbalanced transmission line impedances, phase components are transformed to model components. At last, the fault distance is obtained in model domain. The emulation results of EMTP show that this algorithm not only is of high accuracy and robustness, but also not affected by fault resistance, fault type, fault location and incidence angle of the fault occurrence. The location error is less than 0.5% for all cases.