A Novel Imbalance Compensation Method for High-Speed Railways Considering Energy Storage

There are some methods based on the railway power conditioner (RPC) that can address the imbalance issue, improve load fluctuation, and manage the regenerative braking energy (RBE) of the traction power supply system in high-speed railways. However, the coupling of imbalance compensation and energy storage is a problem in the RPC method. Therefore, a novel decoupling control method is proposed in this paper. The topology of the method is based on a three-phase converter, and the energy storage unit is connected to the DC side of the converter. A decoupling possibility and principle analysis is carried out. The mechanism of the proposed method in coping with different working conditions of high-speed railways is introduced in detail. Then, a capacity analysis and the control method are presented. According to the theoretical analysis, while the traditional RPC requires no extra capacity under single-task operations, its required capacity increases by 15.47% under typical hybrid conditions and can even surge by over 30% under severe coupling scenarios, to achieve the same effect as the proposed decoupled method. Finally, simulations and experiments are carried out to verify the effectiveness and flexibility of the novel method.