Coordinated control method of engine and transmission during shifting process

Abstract

The invention discloses a control method of an engine and a transmission during gear shifting. The control method comprises the following steps: receiving information of a transmission box controller,and if so, judging as an upshifting / downshifting request, wherein an upshifting process comprises the following substeps: acquiring displacement point information of a clutch, entering an upshiftingcoordinated control mode when the clutch is in front of a frictional sliding point, and entering an upshifting rotation speed control mode when the clutch is behind the frictional sliding point; and adownshifting process comprises the following substeps: acquiring the displacement point information of the clutch, entering a downshifting coordinated control mode when the clutch is in front of thefrictional sliding point, and entering a downshifting rotation speed control mode when the clutch is behind the frictional sliding point. During the gear shifting, in the engine deloading and loadingstages, torque is interfered by a transmission box and the output torque of the engine is controlled by an engine ramp function, so that sudden change of the torque of the engine during the gear shifting is effectively reduced. Through closed-loop PID control and rotation speed control which are adopted in the no-load stage of the engine, the rotation speed of the engine can be quickly adjusted toa target rotation speed and the slipping frictional power is reduced.

Description

technical field [0001] The invention relates to a coordinated control method for an engine and a transmission during a shifting process. Background technique [0002] With the development of the automobile industry, vehicles equipped with automatic transmissions have become the mainstream of people's choice. Electromechanical automatic transmissions are improved by adding automatic shifting mechanisms on the basis of traditional stepped manual gear transmissions. The utility model has the advantages of convenience, low manufacturing cost and high transmission efficiency. Since the electromechanical automatic transmission is a stepped transmission, there is a sudden change in the transmission ratio during the shifting process, which causes shifting shocks and reduces driving comfort and smoothness of shifting. [0003] The basic requirements for the shifting process of electronically controlled mechanical automatic transmission vehicles are: the shifting process should be co...

AI Technical Summary

Problems solved by technology

[0005] The above method is a kind of slow torque adjustment method, which often fails to achieve the desired control accuracy and response speed for limited shift time

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