The Design And Experimental Study Of Electro-hydraulic Variable Valve Experiment System Based On High-speed Engine

With the energy crisis and the worsening environmental problems, automobile engine power and emissions standards are getting higher and higher demand in many countries of the world. Energy-saving and emission reduction, high-output torque and power have become the developing goal of auto engine. Practice has proved that variable valve technology is an energy-saving technology that has become a practical and widely application. This paper introduced a high-speed (maximum speed 4000 r/min) car engine variable valve technology based on electro-hydraulic system.This paper describes the research of high-speed (maximum speed 4000 r/min) car engine variable valve timing control technology, for electro-hydraulic-controlled variable-valve principle, proposing the variable valve timing programme based on the electro-hydraulic control system and designing the experimental system. Through the analysis of static and dynamic work characteristics of the system analysis, system has Large-scale pressure changes in the scope of the experiment (maximum 12 MPa), the instantaneous flow of the release of large (45 L/min or so) and so on. Launching high-speed electro-hydraulic variable valve timing system, designing large high-pressure flow sources and selecting key components. Finally, the electro-hydraulic variable valve timing system were studied.There are six chapters in this paper.In chapter 1, Introducing the variable-valve technology background, variable-valve technology and the development of the variable-valve technology. Expounded on issues of significance and the main content of papersIn chaper 2, Launching a high-speed electro-hydraulic variable valve timing control programme, comparative study of the electro-hydraulic control system of variable-valve timing characteristics, the design of electro-hydraulic variable valve timing system of the principle, through modeling analysis of the test system of static and dynamic work, and designing the system's parameters based on the analysis of the system;In chapter 3, Design of the large flow(over 42L/min) and high-pressure(max. 12MPa) sources and the testing system of the electro-hydraulic variable-valve timing experiment system; design and selection of the major system components;In chapter 4, The analysis for the load of the electro-hydraulic variable valve timing system, design of high-speed hydraulic cylinders, the force analysis on the hydraulic cylinders, and the strength, stability, sealed and efficiency analysis; design interface Valve block for the experiment hydraulic system;In chapter 5, Structures experimental platform, select high-frequency electro-hydraulic control valves and rapid response of amplifiers, typical experiment studies on the variable valve timing system, including the valve lift, the opening time and the openning duration, and other characteristics of the work, the verification system is expected design goals;In chapter 6, The author gives the main conclusions of the research, and find in less than a detailed analysis of the reasons for the lack of research to find the next step on the work prospects and expected.