Compound Brake Control for Improved Ride Comfort for Dual-rotor In-wheel Motor Electric Vehicles

Aiming at the problem of braking shock caused by the inconsistent response time of the inner motor (IM), the outer motor (OM) and the hydraulic brake when the regenerative braking mode of dual-rotor in-wheel motor (DRIWM) is switched, this paper proposes a U-shaped transition coordinated control strategy for the DRIWM. Ensure that the total braking torque can be smoothly transitioned when any one or more of the hydraulic braking torque, the braking torque of the IM and the braking torque of the OM enter/exit braking. The dynamic model of electric vehicle (EV) with DRIWMs is established, the division of braking mode is based on the principle of optimal DRIWM system efficiency, and the U-shaped transition coordinated controller of DRIWM is designed. Finally, two cases of switching the IM single braking mode to hydraulic braking mode and OM and hydraulic coordinated braking mode switching to compound braking mode are taken as examples to verify. The results show that, compared with the braking mode switching process without transition coordinated control, the U-shaped transition coordinated control strategy of the DRIWM proposed in this paper can make the DRIWM complete switching within 0.25s on the basis of the optimal system efficiency, which reduces the impact to 2 m/s³ and ensures a smooth transition of the total braking torque when switching.