Large-flow And High-frequency Response Digital Servo Valve

Domestic product in digital valve whose design and research are behind abroad a lot, especially researches in the field of the large-flow and high-frequency response are much poorer (almost blank). Therefore, the study of this thesis is of prime important theoretical and practical significance. As a new type of electro-hydraulic digital control component 2D digital servo valve's (called for short 2D valve) static and dynamic characteristics are good, which can continuously control and can realize minimum dead zone and hysteresis.In this thesis the design of large-flow and high-frequency response digital servo valve, using 2D digital servo valve as pilot component and acting servo screw mechanism as key control technology, gives full play to the advantages of 2D valve performances. In order to achieve large flow, the open amount of valve must be increased. Therefore, the 2D valve is designed into a large stroke displacement control valves in the structure, to control the opening of main valve. In addition, in order to avoid the main valve's flow saturated and ensure design space of the hydraulic circuit in main spool, the neck section of main valve spool is designed into plum-blossom form.Through direct mechanical feedback to the position of main valve, the main valve's displacement is controlled with closed-loop precisely.The thesis's mainly jobs and results are as follows:1. A new structure type of the large flow and high-frequency response digital servo valve is researched and designed. In the second chapter, the valve works are detailed described. And three different projects are designed to comparing and selecting the optimal solution.2.In the structure, pilot 2D valve and main valve are linked by ball link and designed into a whole. In the third,forth and fifth chapter, there were separate description of mathematical model, using the Simulink database in MATLAB software to linearly emulate and analysis 2D valve, and the design and calculations of structural parameters and optimization.3. Experiments show that after increasing the displacement's stroke of 2D valve whose dynamic characteristics is still good, acting as the pilot control valve. The precision of position control of large travel is high, but the response speed is affected in a certain extent.4. The simulation analysis, structural design and experiment results are summarized, and putting forward the shortages and prospects.