Distributed Insulation Monitoring for U.K. 650-V Railway Signaling Power Supplies Using Rectified Current Difference Pattern Tracking

Signaling power is crucial to an operational railway system as any signaling power failure results in serious operational and financial impacts. Therefore, intelligent condition monitoring and accurate fault location are important for the railway industry. This paper introduces a novel distributed insulation monitoring method for railway signaling power system that can monitor continually the resistive earth leakage current and determine the location of the leakage point by tracking the rectified current difference pattern. This method can be used for extended signaling power distribution networks with multiple branches and requires no external power supply or signal injection.