A digital fault location technique for loop transmission systems using three-phase data

The authors present a digital fault location technique using digital fault recorded data for a 115 kV loop transmission system. This technique is based on the use of three phase quantities. The goal of this study is to determine the accuracy of this method and to determine the effects of the different sources of error. Some of the sources of error considered are: the effect of load models; the effect of neglecting loads; the effects of line capacitance; and the effects of untransposition. The method is first tested using steady state fault analysis data, then using simulated transient data generated by using an electromagnetic transient program (EMTP), and finally on actual recorded data. To give a better understanding of this technique, the theory behind it is briefly discussed. The results of test cases determining the accuracy of this technique are presented