Analysis And Optimization Of Wet Dual Clutch Transmission’s Hydraulic Control System

With the rapid development of vehicle handling automation, automatic transmissionhas gained a great progress as a new technology, and been liked by more and more people,which has increased the market share in the automobile gearboxe year by year. As the latestgeneration products, the DCT has become the focus with widespread concern, and has gooddevelopment prospects. That’s because it not only can have the advantage of interruptionshift without power, which the hydraulic automatic transmission and continuously variabletransmission have, but also can have the advantages of High transmission efficiency and soon, which the manual transmission and automatic mechanical transmission have. At thesame time, the essence of mechanical transmission has a good production continuity.Hydraulic control system is one of the most important core parts of wet DCT. Thepaper had been combined with the research of the major projects of "the key technology ofDual Clutch Transmission (DCT)" in Jilin province and made the key technology of wetDCT hydraulic control system’s development as the center, and its main work is as follows:(1)Introduced the application background and significance of the subject, presented thedevelopment history of the Dual Clutch Transmission and the current situation of applyingauto DCT in the domestic and foreign, and analyzed the domestic and foreign researchstatus of DCT hydraulic control system. Combining with the key technology of the wetDCT’s hydraulic control system, the content of this study was introduced.(2)Introduced the mechanism of the DCT hydraulic control system, and introducedcontrol block diagram，the valve, the shifter cylinder and voltage-regulating system of oilsupply one by one. On the basis, the hydraulic principle diagram of DCT’s hydraulic controlsystem was introduced, and the working principle of DCT’s hydraulic control system wasanalyzed. Finally, focused on emphasizing the effect of electromagnetic valve, hydraulicvalve and sensor for the wet DCT’s hydraulic control system.(3)Based on the analysis of DCT’s hydraulic control system, the hydraulic controlsystem of DCT hydraulic was modeled and simulated with the AMESIM software. Thecooling and lubrication model, shift system simulation model and clutch control modulewere simulated, and the simulation results were obtained. On the basis, the total of thehydraulic control system was modeled and simulated in AMESIM, by comparing and analyzing the data curve obtained by simulation and the actual curve obtained by thepractical test, the curve of the parameter optimization was obtained, and the optimizationhad played an important role in simulation.(4)Firstly，doing the design and trial of the hydraulic valve block and testing theresponse characteristics of the solenoid valve by doing the experiments. Besides，Thetransmission bench test was built, and experimental verification of bench test was made.Finally, make the test of DCT’s shifting function, which verified the good effect ofintegration of the control module and the dual clutch module in the whole DCT’s system.This paper had deeply researched on the hydraulic control system on the Dual ClutchTransmission，such as clutch pressure control module, shift gears hydraulic module and theelectromagnetic valve, and so on. These recerch will be helpful to the electro-hydrauliccontrol system’s design and the development of DCT’s control strategy, striving to achievethe combination the accurate electronic control device, which constituted with the hydraulicsystem, made a better complete electro hydraulic control system, establishing a controlsystem of easy control and simple practical. Through the analysis of simulation results， thelaw of output oil pressure changes was obtained by simulatation, combining with someuseful conclusions which were draw from the hydraulic bench test, it was useful for thestructure design of the hydraulic valves, and improving the control of hydraulic system. Ithelped to improve our research and development of dual clutch automatic transmission’scontrol system, improve the matching ability of gear box and other parts of the vehicle, andimprove the efficiency of DCT and shift quality.