Research on Energy Distribution of Regenerative Braking in Station for Contactless Traction Power Supply System Based on Bidirectional Energy Interaction ICPT System

The regenerative braking energy of high-speed railway accounts for about 10% of traction energy consumption, which will be higher under special conditions. The regenerative braking energy feedback of the contactless traction power supply system needs to be realized by dynamic bidirectional inductively coupled power transfer (ICPT). A novel regenerative braking energy distribution method for the contactless traction power supply system based on dynamic bidirectional energy ICPT (DBEI-ICPT) technology is proposed. Then, the mathematical model of the dynamic bidirectional ICPT technology is established; and the variation of transmission power is analyzed; Theoretical analysis of the system energy distribution and its feedback methods. The relationship between the energy flow and the train running state during braking is carried out. After that, an improved train braking curve and control method based on the ICPT technology is proposed, which can satisfy the requirements of the regenerative braking process before the train enters the station by controlling three phase shift angles of the ICPT technology. The control strategy with feedforward control is introduced into the energy storage system to suppress the bus voltage fluctuation. Besides, a nonlinear disturbance observer (NDO) is introduced to solve the shortcomings of the traditional feedforward control methods that require remote measurement. Finally, the effectiveness of the proposed power supply system as well the control strategy is verified by simulation. Results show that the current feedforward bus voltage regulation control is more suitable for this system for its shorter sampling time and stability.