A new method presentation for locating fault in power distribution networks

摘要

Load taps, laterals, and sub laterals are different branches of power distribution (PD) networks. In PD systems, reliability indices and their efficiency are improved using an accurate method in fault locating. In this paper, a new combined method for locating double phase faults to ground is proposed in PD networks. In this article, for finding the possible fault locations, an impedance based fault-location algorithm is used. Then, for determining the faulty section, the new method is proposed using voltage sag matching algorithm. In this method, the possible fault locations are determined, after occurrence of double phase faults to ground, using an algorithm which is impedance based fault-location algorithm. Separately, the same fault is simulated in possible locations. Then, at the beginning of a feeder, the voltage is saved and the amplitude and angle of the voltage differences are determined and accordingly, an online data bank is generated. Then, the obtained and recorded amplitude and angle of the voltage differences (at the beginning of the feeder) is compared with that data bank, for the actual fault. By the matching value of each possible fault location, the real location of fault is determined. Compared to the other counterparts, the proposed method is more accurate in locating faults and less sensitive to the fault resistance.