Cable fault location in medium voltage of Sonelgaz underground network

Abstract

Power supply networks are growing continuously and their reliability is becoming more important than ever. The complexity of the whole network comprises numerous components that can fail and interrupt the power supply. Underground distribution systems are normally exposed to permanent faults, due to specific construction characteristics. In these systems, visual inspection cannot be performed. In order to enhance service restoration, accurate fault location techniques must be used.

The present paper describes the different faults affecting the underground distribution system of SONELGAZ, and cable fault location procedure using Time Domain Reflectometry (TDR) method. This method is based on the analysis of the cable electromagnetic impulse response that allows cable fault pre-location. Results obtained from real tests conducted on underground distribution feeders of electrical network of Energy Distribution Company. The objective of these tests is to know the influence of cable characteristics on the types and frequency of faults, and how the TDR method contributes in obtaining an accurate fault location.

Keywords: Distribution networks - Fault location - TDR (Time Domain Reflectometer) - Underground cable