A Theoretical Analysis on Static Characteristics of Voltage Based Control Method and Current Based Control Method for the Wayside Energy Storage System in DC-electrified Railway

As one of the solution for energy saving in DC-electrified railway system, wayside energy storage systems (WESSs) are recently studied. In the previous study, current based control, which regulates current of ESSs, and voltage based control, which regulates the filter capacitor (FC) voltage, have been proposed as a power control method for WESSs. However, the difference between these two power control methods has not discussed before. In this paper, a theoretical comparison between voltage based power control method and current based power control method is carried out focusing on each static characteristic. Furthermore, an influence of distance between a WESS and a rail vehicle on characteristics of each control is also considered. Though the study in this paper, theoretical comparison between both control methods is carried out. Results of this paper contribute to establish a method to design WESSs which realize maximum energy saving effect with minimum energy capacity of energy storage devices.