Research On Electro-hydraulic Control System Of Seven Speed Opposed Double Clutch Automatic Transmission

Based on the seven-speed opposed dual clutch automatic transmission developed independently by Automotive Engineering and Technology Research Institute of Hefei University of Technology,this paper researchs the electro-hydraulic control system through theoretical analysis and computer modeling and simulation analysis,the main research contents are as follows:(1)In this paper,the mechanical structure of the seven-speed opposed dual clutch automatic transmission and its power transmission route of each gear are analyzed in detail,the shift control logic of the automatic transmission is established.And based on the automatic transmission work principle and shift logic,the transmission electro-hydraulic control system is designed;(2)The various components of the hydraulic control system,including the clutch cylinder,the synchronizer cylinder,electro-hydraulic control valve,analysis their operating characteristics.And the electro-hydraulic control valve,which is two three-way electro-hydraulic valve,is studied deeply,the relationship between the valve's opening ratio and the oil pressure and flow rate output of the control valve is analyzed,and discusses how to control the actuating cylinder of the clutch and the synchronizer by means of the valve opening degree control.The effect of oil pressure loss on valve control was also analyzed;(3)In view of the situation that the two actuating cylinders that appear in the work of the electro-hydraulic control system are moving simultaneously,the interaction between them is analyzed,including the interaction between the synchronizing cylinder and the clutch actuating cylinder,the interaction between clutch cylinders.Then use AMESim software to establish a simulation model and simulation analysis;(4)The hydraulic source of the electro-hydraulic control system is optimized and designed to reduce or eliminate the influence of the interaction between the simultaneously actuated cylinders on the control accuracy.Through analysis,calculation and simulation,the optimized hydraulic pressure source parameters are obtained;(5)The integrated valve block of the electro-hydraulic control system of the seven-speed opposed dual clutch automatic transmission was designed,and the experimental design was carried out according to the research contents;(6)Aiming at the original control system,a new control scheme is put forward,the control scheme is with the stepper motor controls the displacement and the moving speed of the slide valve,instead of with the high-speed on-off valve controls slide valve,and the optimization scheme is introduced.