A novel control method of parallel connected onboard energy storage system for DC-electrified rail vehicle to increase traction motor power

In this paper, increase of traction force and regenerative brake force by increasing DC link voltage is proposed when the overhead line is separated from the traction circuit of overhead line and energy storage device (ESD) hybrid railway vehicle. Furthermore, a method for energy management of ESD during coasting is also proposed. A numerical simulation is carried out to reveal the effect of reduction of energy consumption and achievement of energy management of ESD by applying the proposed control method. The simulation results confirmed that 10.1% and 8.87% decrease of total energy consumption when the DC link voltage is boosted to 1950V is achieved in the case of single and multiple travel between several stations, respectively. Also, the proposed energy management method is verified at 4 patterns of DC link voltage.