Optimization of Control Strategy for Dual-motor Coupling Propulsion System Based on Dynamic Programming Method

The configuration of single-motor direct drive or single-motor coupling with a multi-speed transmission adopted by most domestic battery electric buses has problems such as low overall efficiency and power interruption during shifting. In this paper, a dual-motor coupling propulsion system is proposed for high-performance battery electric buses. Based on the principle of minimum demand electric power, the threshold value of switching between different drive modes of electric drive system is established. Based on the dynamic programming method, the torque distribution control strategy of the electric drive system is optimized in certain drive cycle. Compared with that used the original proportion control strategy, the overall efficiency of the electric drive system is improved, and the power consumption is reduced by 13.6%.