Design And Research Of Digital Controller For 2D Proportional Servo Valve Based On STM32

In recent years,with the increasing demand for automation of mechanical and electrical equipment,higher performance index is proposed in the field of engineering.The electro-hydraulic proportional servo control technology integrated electro-hydraulic proportional control and electro-hydraulic servo control's advantages,which has the advantages of reliable performance,low cost,high control precision and fast response characteristics,so it is widely used and become one of the highlights of the electro-hydraulic control technology.2D proportional servo valve is designed in this paper is the servo screw mechanism using a single spool rotation and sliding of the two degrees of freedom and the realization of the design of power amplifier,the straight-guide control function advantage set in one,relative to other proportional/servo valve,it has the advantages of simple structure,anti pollution ability,zero leakage small,high natural frequency,good dynamic performance.2D proportional servo valve with DC motor as the electro mechanical converter has the advantages of low cost and easy control.At the same time design a digital controller which based on Stm32F405 as the core,the 2D servo valve not only has good static performance,but also has the advantages of miniaturization,integration,low cost,specific research contents and results are as follows:1.The structure and working principle of 2D proportional servo valve are studied.2D proportional servo valve spool with hydraulic servo screw mechanism to overcome the traditional direct-acting single-stage electro-hydraulic valve is difficult to achieve high pressure and high flow control and conductivity control valve structure complex shortcomings.The influence of various factors on the speed of hydraulic servo screw mechanism is studied by MATLAB simulation of servo screw mechanism.2.The theoretical model of the DC motor with 2D proportional servo valve is established.Simulink is used to simulate the motor and its double closed-loop control system.The main phase lag is the limitation of the motor and the phase compensation algorithm is designed Widen the width of the motor.The experimental results show that the rise time of DC motor step response is about 5ms,the dynamic characteristics are good,and the control of 2D proportional servo valve is laid the foundation.3.Stm32F405 clocked at up to 168 MHz,rich peripheral functions and cash floating-point unit(FPU)in one.The digital controller with Stm32F405 and H bridge motor driver chip DRV8844 is designed.The double closed loop PID control of the motor is realized in the program,and the phase compensation algorithm is added to improve the frequency response and stability of the motor.4.The test rig for performance of 2D proportional servo valve is built.The experiments of null position leakage of pilot stage,flow characteristics and dynamic characteristics of 2D proportional servo valve are performed.The experimental results show that the 2D proportional servo valve has good dynamic and static characteristics.