Distributed-drive electric vehicles require coordinated control of four independent motors to perform complex tasks on non-flat roads. However, most existing torque distribution control strategies are designed for flat roads and struggle to adapt to complex slope driving conditions. To address these challenges, this paper proposes a hierarchical torque distribution control strategy that can adapt to slope driving. The impact of road slopes on vehicle dynamics is analyzed, and a dynamic model for distributed-drive electric vehicles under slope conditions is established. A hierarchical controller is then designed based on the current vehicle states and road conditions, with an upper controller that includes a yaw moment controller based on sliding mode control and a longitudinal torque compensation controller based on ESO–PI, while the lower controller integrates optimal distribution and anti-slip control. Simulation results show that the proposed torque distribution control strategy enables the vehicle to effectively track the desired motion states and driving trajectory on low-adhesion slopes and large-slopes. Compared with conventional strategies, the maximum wheel slip rate is reduced by 83.78% on low-adhesion slopes and 76.91% on large-slopes, while tire dissipation energy is reduced by 61.04% and 59.19%, respectively. These improvements significantly enhance vehicle stability, safety, and energy efficiency on slopes.
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