High impedance arcing fault detection in low voltage distribution network

Abstract

Low voltage distribution network should be highly reliable with excellent security. For overhead feeders security is predominantly important. If an unrecognizable quantitative fault occurs at the overhead lines, the above requirement gets violated. Such a violating condition is the high impedance fault. Among all high impedance faults, downed wire problem is the mostly unsecured fault that can occur. Researchers are working on designing an economical protective relay agent for low voltage overhead feeders (400V line-line) to discriminate the fault with high probability of accuracy along with quick detection. The primary objectives of the protective relay agent are reliability and low cost. According to the field and lab experiments, it was found the fault current associated with audible and visible arcing which is significant at the peak region. In this paper, detection algorithm and design steps of a commercial device are described.