Model based development of an integrated control of front steering and torque vectoring differential gear system

Abstract

For future low carbon mobility society, new-type electric vehicles are developed actively in recent period. Those new EVs have integrated power unit which take place of conventional engine, transmission and differential gear components. Additionally it is rather easy to integrate torque vectoring function to those power units using gear sets to control torque distribution between left wheel and right wheel. In this paper, model-based development of an integrated control of front steering angle and torque vectoring differential (TVD) gear system is described. A new control logic was developed using model matching control to let the vehicle yaw rate and vehicle slip angle follow the desired dynamics. Simulation results using a single track model of vehicle dynamics are shown to prove the efficacy of the proposed control. Though, full vehicle model considering all of vehicle dynamics and drive train motion using Modelica clarified the problem of this method in actual cases. Finally modified control was developed and confirmed by both single track model and full vehicle model.