Advanced Control Strategies for High Performance Four-Wheel Drive Electric Vehicle

As the adaptation of Electric Vehicles (EVs) is the future of transportation, there is a significant need to develop control strategies for EVs. The vehicle can lose its controllability during critical maneuvers and conflicting environmental conditions. Hence, to improve the stability of an EV having multiple motors, torque vectoring becomes very essential. This paper aims to develop a torque vectoring control scheme based on Nonlinear Model Predictive Control (NMPC) for four-wheel drive (4WD) EVs (using in-wheel motors). This control scheme, while considering constraints, ensures the vehicle stability by achieving objectives such as tracking desired yaw rate, total torque demand and minimizing the rate of change of consecutive torque inputs. In addition, to minimize the computational effort of the NMPC when dealing with this kind of complex systems, a simple control-oriented model has been built and implemented within the NMPC to enhance the desired objectives. Simulations using a physical vehicle model have been carried out to evaluate the effectiveness of the proposed control approach.