Electric Freight Rail Power System: Capacity Modelling and Simulation, A Statistical Methodology

The capacity of the power system is assessed as a function of the number of trains transiting per day, and of the average time delay between one service and the next. A stochastic element is introduced by randomly varying the time delay between consecutive trains. The random variation of the time-distribution of the trains produces a set of likely traffic scenarios. Each scenario presents a different loading profile to the power system. The response of the power system to train traffic is evaluated by considering the statistical frequency distribution of several electrical and thermal variables for each item of power plant. The risk of electrical parameters to exceed rated values is used to optimise the design of the power system. The advantage of this methodology is that it eliminates the need for a timetable, and that it drives the design of the power system by the estimate of the risk of exceeding rated values rather than by worst case scenarios: this leads to a considerable reduction of the sizing of plant, and thus to a cost saving in economical and environmental terms.