The Clutch Proportional Control Technology Used In High-power Automatic Transmission

This research was carried out by the support of the National High TechnologyResearch and Development Program (2012AA111713) for “The development and researchfor high-power AT transmission” which was undertaken by Inner Mongolia First MachineryGroup Corporation and Beijing Institute of Technology. The shift quality will be promotedby the analysis and optimal design of the high-speed proportional solenoid valve, dynamicanalysis and robust design of the regulator valve, electro-hydraulic shift actuator matchdesign and optimization.The components and operating principle of the electro-hydraulic shift actuator wasdescribed, and the relationship between the proportional solenoid valve, pressure regulatorand clutch has been analyzed; A high-speed proportional solenoid valve for automatictransmission applications was introduced, and the model was established of the valve whichcontains the electromagnetic, hydraulic and mechanical components. The mathematicalmodel of the clutch and regulator were given that leads to the block diagrams of each part.From the established model of the electro-hydraulic shift actuator, it will provide theoreticalsupport for the later actuator analysis and design.For the pilot control of the electro-hydraulic actuator. This thesis presents a high-speedproportional solenoid valve structure can meet the quick, stability requirements for shiftquality control, the dynamic characteristics of the proportional solenoid were analyzed, andalso given the proportional solenoid valve multi-physics coupling relationship, iterativesolution was proposed for multi-physics coupling analysis method to solve the obtainedinformation of the proportional solenoid valve. The action process of the proportionalsolenoid valve was studied by combining with experimental results, verified the correctnessof the coupled simulation model which can be used for the proportional solenoid valvesystem design. The proportional solenoid valve performance achieves the prescribedrequirement in automotive applications.For the flow/pressure control of the electro-hydraulic actuator. This thesis establishesthe system model of regulator valve, and the dynamic analysis of the regulator valve wasanalyzed through simulation and experiment. Sensitivity analysis of the valve structural parameters was fulfilled by Sobol’ method, and robust design of the regulator valve byTaguchi robust methods based on the sensitivity analysis. The valve performance hasimproved after optimal design.For the electric hydraulic shifting circuit, this thesis presents the matching designmethod based on the clutch actuator load and output characteristics analysis. Byimplementing the force act on the clutch force and clutch flow analysis, the optimal designwas carried out with the clutch pressure step response ITAE optimization goal. Thesimulation and experimental results show that the performance of electro-hydraulic shiftactuator was improved by optimization.The torque diagram of each clutch was given after power shifting process of thetransmission were analyzed by leverage method. The clutch/brake oil charge and dischargeprocess was analyzed according to the diagram. The nonlinear model of electro-hydraulicshift circuit was established. By using open-loop and closed-loop control method,experimental studies for the electro-hydraulic shift actuator had been carried out. Theresults show that closed-loop control achieve a smaller tracking accuracy better thanopen-loop control.