رحمن دشتی

Power distribution (PD) networks have many branches, laterals, sub laterals and load taps. Reliability indices and their efficiency are improved using accurate fault locating in PD systems. In this paper, a new combined method is proposed to locate single and double phase faults to ground 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 to determine the faulty section using voltage sag matching algorithm. In this method, after occurrence of single and double phase faults to ground, the possible fault locations 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 a 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 the feeder) for the actual fault. The real location of fault is determined by the matching value of each possible fault location.