Simulation Study On Shift Quality Of Wet Dual Clutch Transmission

Dual clutch transmission is a new kind of transmission developed from manual transmission. It consists of a combination of two sets of clutch, including a clutch shaft nested inside the other clutch shaft, and separately attached with odd and even gears. It is same as AMT when work with a certain shift, maintaining the high efficiency of transmission. When shifting, it can pre-shift, so that the two gears mesh at the same time, and then the two sets of clutch transmit torque by turns to achieve shifting process, which overcome power interruption of AMT in the shifting. Therefore, it can be said that DCT not only has shift comfort of AT, but also has high transmission efficiency of AMT, and has wide application prospects. Shift quality is a study about how to resolve contradiction of quickly shifting and comfort, it also is one of key control technology. This paper focus on the study of shift quality of DCT and relevant content:1. Analysis of the domestic automatic transmission types, advantages and disadvantages and development direction. Describe the key control technology of DCT and domestic and international developments.2. In the second chapter I introduce the representative configuration and working principle detailed. As a instance first stall shift to second stall,I analyze the path power transferred,set up kinetic equation in shifting. Provide a theoretical basis for study on shifting quality.3. Based on estimate index of shift quality,I analyze factors affect shift quality and means improved from the power source and impact of the clutch torque .4. Based on the rapid modeling approach of simdriveline I establish dynamic mold of automobile include DCT.I design fuzzy controller for launch using throttle angle and its change rate as input parameter. In the case of fast launch,slow launch and middle launch on level path,I simulate launch in MATLAB considering driver's intention. I research how the pressure change law affects on shift quality by simulating first stall shift to second stall.5. Using optimization of Genetic Algorithms,I optimize pressure change law in shift by the GA toolbox in MATLAB and simulate the process of shifting. The result of simulation proves that this means of optimization is correct and usable.