Nonlinear controller design for the shift control of dual clutch transmission

To improve the shift quality of vehicles equipped with dual clutch transmissions (DCTs), a feedforward-feedback control scheme is proposed for clutch slip control during the shift inertia phase. The feedforward controller is designed based on differential flatness to track a reference smooth shift trajectory while the proportional feedback controller is to handle the model errors and disturbances. The effectiveness of the proposed controller is verified on a complete AMESim powertrain model for upshift and downshift cases. Moreover, to facilitate the implementation of the controller, the feedforward part of the derived controller is simplified based on lookup tables, which helps to avoid complex calculations. Finally, comparison results between the normal controller and lookup table-based controller show the effectiveness of the lookup table-based controller, and a smooth shift can be provided still.