Research on Transmission Gearshift Control in Hybrid Vehicles

The gearshift strategy of the P2.5 hybrid system is based on the final desired gear control, the shift type and sequence control and the clutch coordination. The specific contents are as below: 1)The final desired gear control. The part determines the engaged gear and engaged clutch based on the information which includes the base gear request from shift schedule, the passive gear request, the gear request dependent on the gear lever, the engine clutch start gear request and the efad gear request. 2) The shift type and sequence control. The different shift types are torque interrupt, the power shift, the supported power shift, the intermediate shift, the from neutral shift and the to neutral shift. The different shift type has the different sequence which is defined in the correct order. 3) The clutch control. The speed targets for clutch control and torque intervention to the engine based on the commanded clutch state from the sequencer is calculated in this part. The vehicle results are conducted and show that the gearshift strategy can meet the request of the driver and the good drivability performance can be achieved.