Torque Vectoring and Multi-Mode Driving of Electric Vehicles with a Novel Dual-Motor Coupling Electric Drive System

Highly integrated and efficient electric drive technology for improving the comprehensive performance of electric vehicles stands as a prominent research focus. This paper proposes a novel dual-motor coupling electric drive axle incorporating torque vectoring (TV) technology, aiming to enhance driving maneuverability and further improve vehicle efficiency. Firstly, the configuration of the dual-motor coupling drive-axle is analyzed, introducing its four operational modes: main drive motor independent drive mode, TV motor independent drive mode, dual-motor torque coupling drive mode, and torque vectoring drive mode. Subsequently, to unlock the energy-saving potential of the dual-motor coupling drive system, optimization of the drive-mode division is conducted. This optimization selects the work mode with minimal energy consumption under the specified speed and torque requirements. The switching logic thresholds for optimal work mode boundaries and their buffer zones, designed to mitigate frequent switchover, are established in the equivalent external characteristic map of the dual motors. Finally, the co-simulation validates the torque vectoring function and driving economy. Results indicate that positive or negative torque vectoring can be strategically employed to enhance driving maneuverability or stability, respectively. The optimized multi-mode driving of the proposed dual-motor coupling electric drive-axle demonstrates a reduction in energy consumption by 7.28%, 7.35%, and 8.54% under NEDC, FTP-75, and CLTC work conditions, respectively, in comparison with a single-motor drive-axle with equal total power.