| As the engine becoming more intensify and its speed increasing more quickly, the development and application of variable valve train getting more and more urgently. But up to now there is no valve train can satisfy the requirements of exploit the maxim advantages of variable valve train as well as working with high efficiency as the conventional admission gear. Electromechanical valve actuator (EMVA) is one of the latest developments of variable port timing. It can satisfy the compromise of performance, cost and reliability. So it is a very effective method to realize lower fuel consumption and exhaust emissions. In the world there are many well-known universities and companies, which are developing the electromechanical valve actuator with vast human resource and funds. But whether its structure or control method is not perfect, so it need farther development in the future.This dissertation investigates it on the basis of a host of reference, and combines the real situation of the subject, which is cooperating with Wuxi Fuel Injection Equipment Research Institute. A comprehensive study pattern, the integration of analysis, simulation, test and manufacturing, is applied to develop electromechanical valve actuator with high performance..Main works are as following:1. The mathematical model of electromechanical valve actuator is simulated by the MATLAB/SIMULINK software. According to the study of the system's operational mechanism, the effect of various parameters of electromechanical valve actuator on its operation process is revealed. It can provide reliable parameter and foundation to the mechanism design. The computer-aided simulation has many advantages compare to the test, such as low cost and short development cycle. It not only can reduce test times, resources, but also can discover new laws and phenomena. An electromechanical valve actuator set-up, which used silicon sheet as magnetic conductor was designed firstly based on the simulation result and the development experience of foreign company.2. The control theory of electromechanical valve actuator is studied firstly on the basis of its mathematical model. Two kinds of control methods are also presented, simulation results show that Feedback-Feedforward Iterative learning control hasmore significant potential than the PID control method. The learning control algorithm used in this paper can satisfy the trajectory tracking quickly. It provides a capable theoretical method to solve the soft-landing problem, which is the maximum obstacle for the electromechanical valve actuator's practical development.3. The electronic control unit for electromechanical valve actuator is designed. The process is carry out by the hardware for driving of solenoid and the software for real time control. The hardware designing of ECU includes the selection of the microcomputer, simulator and sensors, designing of driving circuit, etc. The software designing includes demands of electronic control unit, software structure and function, software module analysis and flow chart.4. The static state measuring system and the dynamic state measuring system are developed firstly for electromechanical valve actuator. By the measuring systems, the electromagnetic characteristics and parameters related to operation process of EMVA can be analyzed. Based on the results, modified design of EMVA and its measuring system are put forward. Experimental results demonstrate that the performance of measuring system can realize the static state and dynamic state measurement of electromechanical valve actuator, the EMVA mechanism can meet the requirement of powerful magnetic force, further development are anticipated for the valve's transition time and soft-landing.
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