Development of an Integrated Control of Front Steering and Torque Vectoring Differential Gear System Using Modelica

To satisfy needs for future low-carbon mobility society, development of many new EVs is increasingly active in recent years. Additionally many new proposals about integrated electric power train which also has torque vectoring capability are presented (Höhn et al., 2013). (Burgess, 2009) showed a model-based control design of TVD using an inverse model for feed-forward control. (Efstathios et al. 2015) introduced a model predictive control of TVD considering non-linear tire characteristics. On the other hand, authors have researched a new control of TVD by using traditional PI feedback control (Hirano et al., 2013) (Hirano et al. , 2014). The author also utilized a model matching control theory to develop a new control of TVD (Hirano, 2016a). Additionally the author expand the control to the integrated control of TVD and active front steering (AFS) by model matching control (Hirano, 2016b). The purpose of using both TVD and AFS is to control both vehicle yaw rate and slip angle independently. In the last paper, the derived control was based on simple LQR (Linear Quadratic Regulator) and there was no measure to cope with steady state deviation. In this paper, the LQR design was modified by augmenting the plant model to include integral of the state variables. As same as the last research, an extended single track model of vehicle dynamics was used to derive and verify the new control. Finally the developed control was verified by using the full vehicle model using Modelica. Some measures about solving problems when applying Modelica to this kind of problem are also mentioned.