A Reactance-Based Fault Location Method for Overhead Lines of AC Electrified Railway

Aiming at solving the problems of substantial error in the existing methods due to mutual reactance in locating the catenary-to-ground fault of a two-track railway system(TTRS), a novel fault location method considering mutual reactance is proposed. The proposed method can effectively eliminate the influence of mutual reactance on fault location. In addition, the fault location can obtain from fault reactance measured at line circuit-breaker of the traction substation. Simulation results show that the proposed method can obviously improve the accuracy of fault location.

I. Introduction

Overhead lines, also called overhead catenaries in railway system, provide a single-phase 25 kV, 50 Hz AC supply to electric trains in many countries. In the TTRS, the overhead line equipment is comprised of two electrically independent catenaries running in parallel. Due to the nature of railway system, catenary-to-ground faults are common. The fault location is very important for shortening power outage time and ensuring transportation order [1].