Evaluation of Maintenance Schedules on Railway Traction Power Systems

Abstract In electrified railways, the traction power systems carry power to trains and their reliability is vital to the quality of train services. There are many components in the traction power system, from interface with utility distribution network to contacts with trains, and they are physically located along the rail line. Subject to usage, environment, and ageing, conditions of components deteriorate with time. Regular maintenance has to be carried out to restore their conditions and prevent them from failure. However, the decisions on the suitable length of maintenance intervals often lead railway operators to the dilemma of minimizing both risk of failure and operation cost. On the basis of a stochastic lifetime model, this article presents a generic software evaluation tool that enables the operators to manage risk of failure and cost quantitatively in order to match their preferred levels of service quality. The lifetime model includes the effects of condition restoration because of maintenance of regular intervals and ageing acceleration because of electrical stress from traffic demands. Examples of simulation results are given to illustrate the applicability of this lifetime model.