A drive system global control strategy for electric vehicle based on optimized acceleration curve

Abstract

The existing researches of electric vehicle (EV) drive system mainly focus on the motor itself, without considering the EV energy consumption and battery life simultaneously. Thence, in this paper, a control method of EV drive system based on its energy consumption and battery life is proposed. Combining the EV driving state with the motor control, the relationship between the velocity and acceleration and the optimal dq-axis currents is established. Then, a drive system global control strategy for EV based on optimized acceleration curve is proposed, in which the maximum torque per ampere (MTPA) control is used below motor base speed and the voltage closed-loop feedback flux weakening control is used above motor base speed. Furthermore, the proposed control strategy is verified by both MATLAB/Simulink simulation and experiment. The simulation and experimental results show that compared with original working conditions, the energy consumption per kilometer and the percentage of battery capacity loss per kilometer of the global control strategy based on optimized acceleration curve are both reduced, which verifies the feasibility and effectiveness of the proposed control strategy.