Research on the Oscillation Reduction Control During Gearshift in Hybrid Electric Vehicles

In order to realize the shift control of dual-motor hybrid electric vehicle (HEV), a non-power interruption shift control method based on three-power source coordination control was proposed by analyzing the shift process of dual-motor hybrid configuration. The shift control process was divided into three stages: oil-filling self-learning stage, torque exchange stage and inertia control stage. In the torque exchange stage, the characteristics of the speed stage and torque stage were analyzed, which was different from the traditional method's dependence on pressure sensor, longitudinal acceleration sensor and engine torque accuracy. A shift clutch gain self-learning strategy based on shift time and input shaft speed soaring problem was proposed. In the shift process, the parameters were adjusted by self-learning, and the shift time after learning could gradually approach the set target value, and the input shaft speed soaring phenomenon could be gradually eliminated, and the shift quality was significantly improved, which ensured the consistency of shift quality after different vehicles, different engines and different transmissions were integrated, as well as the consistency of driving performance of the vehicle in the product life cycle. In the inertia control stage, The torque intervention strategy has been used in this paper to shorten the inertia phase time to meet the driver's intention quickly. The results show that the time of inertial phase can be greatly shorten by the intervention control of shifting inertial phase and the adaptive method in this paper can effectively detect the shift time too long or too short and flare shift anomalies during the shift process.