| With developing of automobile industry, automobile transmission is continuously weeding through the old to bring forth the new. Metal V-belt type CVT is the latest type vehicle transmission that was pushing out in the modern time.Base on detaching a P811 style metal V-belt type CVT, produced by VDT co. Dutch, this paper analyzes and studies the transmission's general construction, constitution of hydraulic control system and its operating principle.In the paper, P811 style metal V-belt type CVT 's general construction is introduced, and the constructions and operating principles of all of the transmission are analyzed. Because the characters of engine are far more important for analyze the control processes of the hydraulic control system of transmission, so this paper introduces the characters of automobile engine simply in this part.In the paper, the construction of hydraulic control system f P811 style metal V-belt type CVT, the construction of all control valves and the operating Principle and control process of the hydraulic control system are introduced fully. First, the constructions of all control valves of the integrated hydraulic control valves are introduced. The control processes of each control valve are decelerated, the oil circuit graph of hydraulic control system is given and the operating principle and control process of hydraulic control system are analyzed and researched, the experimental curve of the P811 style metal V-belt type CVT is interpreted, and the variable rule of velocity ratio under all conditions are analyzed.In the paper, method of bond graph and method of transfer function analysis are used separately to create mathematical models of hydraulic control systems, the construction parameters determined, and calculation formulas of spring forces, valve port damps and initial through-flow areas are given. According to the mathematical model from method of transfer function analysis.Base on detaching a P811 style metal V-belt type CVT. The author designed "Electronic and Hydraulic Proportion Control Continuously Variable Transmission (ECVT). Method of fuzzy control is used to control and research. The method dose not need get close to the model extraordinarily, and the in-put request of control system is not very high. Compare with the method and PID Control, the conclusion is that using method of Fuzzy Control improved System Performance. Using overall situation approimant characteristic of the fuzzy logic system and combining with the sliding model control theory, the author put forward a kind of direct fuzzy self-adaptive control strategy on a kind of system with nonlinear interference. Therefore, the controller designer by the author has following characters: possess precise math analytic formula with simple construction, do not need more earlier-knowledge, ensure the system stable and following error convergence within zero-neighborhood.The experiment test is carried out at last in the paper. The experiment control system is used to developing test by single board computer system. The model that designed before is used to emulate research. This emulation model mainly operated by. MATLAB language, the software is usually combining with function base and user self-definition function, it is greatly simplify the emulation work, and improve the efficiency. Emulating to the model is according to the different peter conditions and earlier-knowledge; obtain the conduction to the offer the theory for the next step.The paper designed a CVT electronic control single board computer system. It is basically realize that the purpose the data in-put, out-put and display. The results of the final experiment indicate that the design method of mathematical models and control system are coffect.
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