I. Introduction
THE power distribution system consists of a three-phase source supplying power through single-, two-, or three-phase distribution lines, switches, and transformers to a set of buses with a given load demand. In addition, unlike transmission systems, single-, two-, and three-phase sections exist in the network and single-, two-, and three-phase loads exist in the distribution networks. Further most distribution systems are overhead systems, which are susceptible to faults caused by a variety of situations such as adverse weather conditions, equipment failure, traffic accidents, etc. When a fault occurs on a distribution line, it is very important for the utility to identify the fault location as quickly as possible for improving the service reliability. A fault location in the distribution system (DS) is not an easy job due to its high complexity and difficulty caused by nonhomogeneity of line, fault resistance, load uncertainty, phase unbalance, long feeders with laterals and different network configurations under various load conditions [1]. Hence, one of the crucial blocks in the operation of such a DS is that of fault detection and it's location. This objective is achieved and depends on the success of the Distribution Automation (DA) System. The DA system should be implemented quickly and accurately in order to isolate those affected branches from the healthy parts and to take countermeasures to recover normal power supply.