Hamid Afradi; Javad Sadeh

Abstract
This paper presents a new algorithm for locating faults in a combined overhead transmission line with underground power cable using Adaptive Network-Based Fuzzy Inference System (ANFIS). The proposed method consists of two parts. At the first part, the section of fault is determined, and in the second part, the exact location of fault in overhead or underground section is calculated. Three ANFIS networks are learned and tested to achieve these goals. The first one for section detection the two others for locating fault on overhead or underground parts. The input data of ANFISs consist of the dc component of current, fundamental frequency of the voltage and current and the angle between voltage and current phasors. The proposed method is evaluated in different conditions such as different fault location, different fault inception angles and different fault resistances. The results of  omputer simulation confirm the accuracy of the proposed method.