Reliability and life evaluation of a DC traction power supply system considering load characteristics

The traction power supply system is one of the most important parts of a railway system, which is responsible for providing electricity to power the running trains and other operating equipment. The performance of the power supply has a profound impact on the railway system. Therefore, it is necessary to conduct research on the reliability of the power supply system considering traction load and ensure it is highly reliable. This paper introduces some reliability-related indexes based on the Fault Tree Analysis (FTA) method and proposes a method to evaluate the system reliability of a DC-electrified railway. The effect of traction load on power supply system reliability is studied based on IEEE standards. A dynamic reliability and life evaluation model is built up to evaluate the reliability of traction substation and to develop a plan to reduce the operational risk of the power system. Through analysis of a practical example of the Singapore East West line, the system reliability and remaining useful life of each traction substation are obtained. The outcome from this study provides guidance for the maintenance and future operation plan of the power system.