رحمن دشتی

Power distribution (PD) networks have many laterals and load taps. Accurate fault locating in PD systems causes to improve reliability indices and its efficiency. In this paper, a new combined method is proposed for locating single phase fault to earth in PD networks. In this article, an impedance based fault-location algorithm is used to find the possible fault locations. Then the new method is proposed for determining the faulty section using voltage sag matching algorithm. In this method, after occurring single phase fault to ground, the possible locations of fault are determined using the impedance based fault-location algorithm. The same fault is simulated in possible locations, separately. Then the voltage at the beginning of feeder is saved and the amplitude and angle of the voltage differences are determined and online data bank is generated. This data bank is compared with the obtained and recorded amplitude and angle of the voltage differences (at the beginning of feeder) for actual fault. The real location of fault is determined by the matching value of each possible fault location.