| Taking the advantage of economy, utility, and so on, the technology of electro-hydraulic proportional valve control has become an important branch of modern control, which has been applied extensively in military use, civil use, industry, and other mechanical industries, and become an important index of industrialization level of a country. With introducing of embedded technology, it makes the controller of electro-hydraulic proportional valve more digital, intelligent and networking.Based on the status of the development of proportional cotroller and existing related equipment, the main research work include as follow:First, analyze the situation and trend of the past, present, and future of electro-hydraulic proportional control technology and electro-hydraulic·proportional controller both at home and abroad, and conclude that it is feasible and necessary to research on this project.Second, analyze the characteristic of proportional magnet and proportional flow valve and established the corresponding mathematical model of control object.Third, according to above and actual measurement, give out the general frame of electro-hydraulic proportional flow valve controller based on LPC2290 MCU and allocate the resource of LPC2290. Particularly, design PWM power drive circuit, state display circuit, displacement feedback circuit and common V/I and I/V circuit. Some of them has two schemes and simulate by Multisim software,which shows the circuits is ideal. Furthermore, designed A/D and D/A circuit, and so on.Forth, for the nonlinear compensation of electro-hydraulic proportional flow valve controlling, get the datum of flow characteristic curve and load characteristic curve from supplier's specification, fit them by MATLAB related tool box, and analyze their errors. At last, figure out a final founction which can calculate the flow value at any pressure differential and any command value.
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