Existing torque distribution control strategies for four-wheel independent drive electric vehicles have limitations in maintaining stability under challenging driving conditions such as rapid steering and on low-friction roads. Therefore, a more adaptive torque distribution strategy is needed to enable the vehicle to cope with these driving conditions and ensure its stability and safety. This paper proposes an improved torque distribution control strategy that distributes the motor torque based on the weighted contribution of each tire force to the yaw moment. As a result, vehicle stability can be achieved with less motor torque output and yaw moment can be generated in the most optimal way. Simulation examples show that the proposed control strategy is effective for driving under conditions of low-friction roads and rapid steering. The influences of friction coefficient and variation of the vehicle center of gravity are particularly considered in the control strategy formulation. Moreover, it is shown that the proposed strategy is more effective than some existing algorithms, under high-friction conditions, the path error is reduced by 10%, and the torque output decreases by 53.5%. Under low-friction conditions, the path deviation decreases by 57.3%, accompanied by a 65.9% reduction in torque output.
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