A Stability Control Scheme for Four-Wheel Independent Drive Electric Vehicles Considering IGBT Thermal Effect

Under high load conditions, the insulated-gate bipolar transistor (IGBT) modules for four-wheel independent drive electric vehicle (4WIDEV) are at risk of overheating, making it susceptible to triggering the designed thermal protection strategy (TPS). TPS lowers the temperature of IGBT module by decreasing the motor output torque, but this adversely affects vehicle stability. To solve this problem, a stability control scheme for 4WIDEV considering IGBT thermal effect is proposed. Firstly, an IGBT thermal model is established based on the IGBT power losses analysis. Secondly, a model predictive control (MPC) framework is developed, utilizing the vehicle dynamics model and IGBT thermal model, which considers the IGBT temperature constraints and the over-actuated feature of 4WIDEV to achieve the optimal torque allocation. Finally, the proposed control scheme is verified through Matlab/Simulink and CarSim co-simulation. The results indicate that it effectively adjusts each motor's output torque in advance, ensuring vehicle stability while avoiding triggering the designed TPS.