The Simulation And Optimization On The Gear-shifting Without Concussion Of DCT

The dual-clutch transmission (DCT) in recent years a new type of transmission,which combines the hydraulic automatic transmission’s advantages that shiftsmoothly and the manual transmission’s advantages that the transmission efficiencyand low-cost advantages, and abandoned the shortcomings of both. Has a naturaladvantage in power and economy of the vehicle, which makes the DCT become thetrend of the development of the automatic transmission. In the development processof the DCT, the shifting process control strategies and the life of the clutch problem isthe technical difficulties, due to the life of the clutch shifting process largely dependson the friction work, so these two issues can be attributed to a issue that the shiftquality of the DCT. This paper start from the DCT-shift control strategy and made aseries of studies designed to improve shift quality of the DCT. Details are as follows:(1) Introduce the major component of the dual-clutch automatic transmissionsystem, and analyzed the structure and working process of the DCT transmission.(2) To establish a simplified model of the DCT shift and take the two files litersthird gear for example on this basis,and made a detailed kinetic analysis of theprocess of shifting, and establish the corresponding mathematical model.(3) From shifting performance requirements, proposed that take the jerk and thefriction work as shift quality’s guide line, and analysis the factors affect the shiftquality, and proposed to improve the DCT shift quality by integrated control of clutchand engine.(4) Deduced the method shifting with no impact on the basis of the shiftingdynamics. It means to realize the purpose of shifting smoothly and without impact byprecise control the two clutch oil pressure and engine throttle, and simulate and verifyby the Matlab/simulink.(5) In order to comprehensive control jerk and the friction work on the shiftingcourse, that need reasonable optimize for two clutch hydraulic relationship of shiftingtime and the shift with no impact. Then simulate the optimization process by simulink,and determine the parameters of optimal shifting by the simulate results. Finally, takeparameters of the optimal shifting as the input object to simulate and verify theshifting process. The results show that the optimize of shifting with no impact cancontrol jerk and the friction work t in the shift process, and improve the shift qualityof the vehicle effectively.