Analysis of Power Flows in a DC Railway System with Hardware-in-the-Loop Simulation

DC railway systems have great potential for improvements in their total energy consumption. In these systems, the available braking energy is dissipated when there are no nearby trains. Thus, adding energy recovery devices (e.g., substation inverters or energy storage systems) would enable the reutilization of the braking energy. However, the placement of any solution on the supply line must be carefully studied beforehand. This paper presents the development of a Hardware-in-the-Loop simulation of a DC railway system. It consists of a numerical simulation of the traction system of a train (with its control and braking strategy) and reduced-scale hardware of a traction power substations and the supply line. This simulator could be used as a decision-making tool for improvements on DC railway systems.