A simulation-based approach for determination of the traction chain efficiency for multiple train trajectories

Abstract

The increasing energy demand and sustainability goals requires careful planning of resources, and simulations are instrumental in this. For train traffic, determining the precise parameters governing resistance, vehicle efficiency, and common driver behaviour is still an open problem, due to the variability of those characteristics. Normal approach is to use test drives or test systems, and assumptions for driver behaviour. We use existing measures of energy (currently used for billing) of revenue-making conventional train runs with varying trajectories. We combine this with infrastructure data, and vehicle parameters by a replaying the recorded trajectory in a simulation system. We estimate an aggregated measure of efficiency, and a mix of regenerative and dissipating braking usage. For the Swiss train DPZ, for which comprehensive tests are available, the determined traction chain efficiency deviates from the manufacturer's value of less than 1-2 %.