Torque-vectoring stability control of a four wheel drive electric vehicle

The electrification of the automotive powertrain provides completely new control options regarding the distribution of individual wheel moments. The integration of up to four independently controlled electrical engines in a vehicle allows individual adjustment of driving and braking torques to the current driving situation. Thus, electrical engines create a new kind of dynamic vehicle control. Unlike the Electronic Stability Control (ESC), Torque-Vectoring influences the vehicle dynamics not only through braking forces but also by setting up positive driving torques allowing for a new way of dynamic driving. In this paper two different control algorithms are developed in order to calculate a desired yaw moment to influence vehicle dynamics. The Torque-Vectoring algorithm distributes the yaw moment among the four wheels. The evaluation of the vehicle dynamic simulation has shown that the best results regarding the control quality can be reached by using the Fuzzy control algorithm to optimize the driving stability in extreme driving situations.