Clutch engaging phase linearization-based mode switching control method for parallel hybrid powertrain

The parallel hybrid powertrain system can efficiency improve fuel economy by the mode switching under complex driving conditions. However, the mode switching control is challenging due to the non-linear clutch engagement process. To overcome this challenge, this paper proposed a clutch engaging phase linearization-based mode switching control method for the clutch engagement in the parallel hybrid electric vehicle (HEV). Firstly, a detail model is built to describes the engagement process of clutch, and the three phases with the same characteristics is divided. Then, according to the jerk and time indicators, the law of expected friction torque change is calculated and verified. Finally, in order to track the desired friction torque change rule to complete the mode switching, a phased mode switching control method, include two feed-back position control algorithms and a feed-forward torque control algorithm, is proposed. The simulation results verify that the relationship between the friction torque change and the jerk is reliable, and the proposed control method can effectively track the trajectory of the desired friction torque, and the jerk is less than 10m/s
³
during the mode switching process.