Hydraulic Clutch Fill Control using Control-oriented Model in Wet Dual Clutch Transmission

This paper proposes a control method for filling phase of a hydraulic clutch actuation system in wet dual-clutch transmission (DCT) based on a control-oriented model. In wet DCT, a clutch-fill process cannot obtain proper fill and maintain under-fill due to the drag torque, which causes bad shift performance. In this paper, in order to compensate the filling phase, a control-oriented model considering practical issues is proposed. The proposed model is used to design a model-based controller to track a desired pressure in filling phase. The designed controller is composed of feed-forward part contains model information for fast response and convergence, and feedback part that compensates modelling errors or uncertainties. In order to verify the proposed controller, simulation based on an exact model of hydraulic clutch actuation system is constructed. Simulation results reveal that the proposed controller guarantees good pressure tracking performance in filling phase for various situations.