Efficient Direct Yaw Moment Control during Acceleration and Deceleration While Turning (Second Report)

Electric vehicles (EVs) are attracting attention due to growing awareness of environmental issues such as fossil fuel depletion and global warming. In particular, a wide range of research has examined how direct yaw moment controls (DYCs) can enhance the handling performance of EVs equipped with multiple in-wheel motors (IWMs) or the like. Recently, this research has focused on reducing energy consumption through driving force distribution control. The first report proposed a method to minimize energy consumption through an efficient DYC for extending the cruising range of a vehicle installed with four IWMs, and described the vehicle behavior with this control. Since motors allow high design flexibility, EVs can be developed with a variety of drive systems. For this reason, various driving force distribution control methods can be considered based on the adopted system. Widespread adoption of the optimum driving force distribution control method for each drive system from the standpoint of energy consumption should be achievable using the results described in the first report. Consequently, this second report examines a control method to minimize energy consumption for vehicles with different motor-based drive systems. The driving force distribution control laws to minimize energy consumption in a vehicle with two or three motors were calculated and compared to a vehicle with four motors. This paper also compares the energy consumption when turning while accelerating or decelerating, and discusses the vehicle behavior in these scenarios. The derived control laws can be applied to vehicles with any motor-based drive system.