Accurate one-terminal fault location algorithm based on the principle of short-circuit calculation

Abstract

An alternative method to find the line fault distance in a transmission network employing only one-terminal measured data is presented. The proposed method applies Zbus for short-circuit calculation to find the fault location on a transmission line without the necessity to know the fault type a priori. The well-known drawback of the standard simple-reactance one-terminal algorithm, which neglects the effect of fault impedance, will be minimized by estimating the voltage drop at the fault location by employing the Zbus technique. Accuracy the proposed method is demonstrated using the short-circuit simulation of the modified IEEE-14 bus test system on MATLAB/Simulink and the Simpower Toolbox. Compared to the accuracy obtained from the standard one-terminal algorithm, test results confirm substantially improved accuracy of the proposed method in all cases of the four types of fault categories: single line-to-ground fault; double line-to-ground fault; line-to-line fault; and balance three-phase fault. While the accuracy has been significantly improved, especially for the case with a relatively high fault impedance, also the simplicity in the involved computation is well preserved when compared to other iterative-based techniques. © 2012 Institute of Electrical Engineers of Japan.