A Power Control Method to Save Energy for Wayside Energy Storage Systems in dc-Electrified Railway System

The introduction of wayside energy storage systems is effective for the recovery of regenerative brake energy in dc-electrified railways. However, considering the cost of their deployment, it is preferable to maximize the energy saving effect with a minimum capacity of the energy storage devices (ESDs). In this paper, we propose a power control method that can improve the energy saving effect while managing the energy of the ESDs. The proposed method is implemented by controlling the filter capacitor voltage of the line side of the power converter for the ESDs depending on their energy and the line voltage of the overhead contact line to which they are connected. Next, the proposed method is verified by numerical simulations and experimental tests with a 1 kW class downsized model.