System for locating faults and estimating fault resistance in distribution networks with tapped loads

摘要

Both fault location and fault resistance of a fault are calculated by the present method and system. The method and system takes into account the effects of fault resistance and load flow, thereby calculating fault resistance by taking into consideration the current flowing through the distribution network as well as the effect of fault impedance. A direct method calculates fault location and fault resistance directly while an iterative fashion method utilizes simpler calculations in an iterative fashion which first assumes that the phase angle of the current distribution factor Ds is zero, calculates an estimate of fault location utilizing this assumption, and then iteratively calculates a new value of the phase angle beta s of the current distribution factor Ds and fault location m until a sufficiently accurate determination of fault location is ascertained. Fault resistance is then calculated based upon the calculated fault location. The techniques are equally applicable to a three-phase system once fault type is identified.