Hybrid regenerative braking energy utilization system and its control strategy in urban rail transit

Aiming at the utilization problem of regenerative braking energy（RBE） in urban rail transit，hy⁃ brid RBE utilization system（HRBEUS） combining energy feedback system and energy storage system and its control strategy are proposed considering load characteristics of power supply system in urban rail transit. The topology of HRBEUS is proposed considering the structure and load characteristics of power supply system of urban rail transit and the operating principle of HRBEUS is analyzed. Aiming at the full utiliza⁃ tion of RBE，the energy management strategy of HRBEUS is formulated to realize the power flow manage⁃ ment under various operating modes and conditions. Moreover，a hierarchical control strategy of HRBEUS combining the DC bus voltage control and the dynamic power allocation is proposed. The validity and fea⁃ sibility of the above design are verified by simulation analysis，and the indexes of different RBE utilization schemes are compared. The results show that the proposed hierarchical control strategy can coordinate the control system to feedback，store and release RBE on demand，so as to realize the full utilization of RBE of urban rail transit，and restrain the DC bus voltage variation effectively. At the same time，the proposed HRBEUS can better take into account the technical effect and economy，and has certain advantages com⁃ pared with energy storage scheme and energy feedback scheme，so it can be used as one of the choices of RBE utilization scheme in urban rail transit. © 2023 Electric Power Automation Equipment Press. All rights reserved.