Design Of Industrial For Two-dimensional (2D) Servo Valve And Its Dual Redundancy Controller

The electro-hydraulic servo valve has many advantages,such as fast dynamic response and strong durability.Based on these advantages,electro-hydraulic servo valve is widely used in aerospace and military industry.When the servo valve works,the reliability of the controller directly affects the reliability of the servo valve.Compared with the military servo valve,the industrial servo valve simplifies the mechanical structure,appropriately reduces its performance,and the manufacturing cost is relatively low.Therefore,this paper studies and designs industrial two-dimensional(2D)servo valve and its dual redundant controller,and to some extent increases the reliability of the controller and the valve.The control object of this paper is industrial two-dimensional(2D)servo valve.The anti pollution performance of the servo valve increases,the frequency response is rapid and the cost is low.The electro-mechanical converter of servo valve is a two-phase hybrid stepping motor.In order to solve the contradiction between the speed of motor response and the resolution of motor,a closed-loop control algorithm of motor rotor angular displacement is proposed to make the rotor stay in a fixed position.In order to improve the accuracy of servo valve,a closed-loop control algorithm of servo valve spool position is proposed based on the closed-loop algorithm of motor rotor displacement.? The controller with double redundancy function is designed to control the motor,and then the servo valve is controlled by the lever and fork mechanism.The electro-mechanical converter and servo valve are simulated under the corresponding closed-loop control.Finally,the motor and servo valve are tested.The specific design results are as follows:(1)the structure and principle of two-phase hybrid stepping motor are studied.The tracking control algorithm of synchronous motor rotor displacement is proposed,and based on this algorithm,the mathematical modeling and Simulation of the motor are carried out.Through the simulation data,the static and frequency response characteristics of the stepping motor are good.It can be concluded that the stability of the motor is good,the response speed is fast,the frequency width is about 155 Hz,and the rise time of the dynamic step response can reach about 4.6 Ms.(2)the principle of industrial two-dimensional(2D)servo valve is analyzed and the servo screw mechanism of servo valve is modeled and simulated.It can be concluded that the frequency width is 48 Hz,and the rise time of dynamic step response can reach about 4.0 MS,which shows that the response speed of the valve is fast and the dynamic characteristics are good.The closed-loop control of valve core displacement based on synchronous tracking control algorithm of rotor displacement of servo valve is proposed.The algorithm is used to simulate the dynamic and static characteristics of the servo valve.The frequency width of the servo valve is 45 Hz,and the rise time of the dynamic step response can reach about 6.7 Ms.(3)the dual redundant controller of industrial two-dimensional(2D)servo valve is designed.The stability of power supply of the power board directly affects the working condition of the whole circuit.In order to ensure the reliability of the power board,the power board adopts double redundancy design.When one input protection module of the power board fails,it can automatically switch to the other input protection module,and the input protection module has alarm and protection functions such as anti reverse connection.The main control board also adopts double redundancy function design.The main control board adopts stm32f407 as the main chip,and two minimum system modules are designed.When one main control module fails,the optical relay is used to cut off the power input of the circuit,and then switch to the other standby main control module to ensure the normal execution of the main control program to a certain extent.Because the servo valve is more important than the controller,the stability of the drive module can reduce the damage of the servo valve,so the drive module is the core of the main control board,so the drive module also adopts double redundancy design,to ensure that when the main drive module fails,it can use the optical relay to automatically switch to the standby drive module.The driver chip adopts drv8873 s.In order to further master the working condition of the driver module,the driver module has over-voltage,under voltage,over temperature,over-current and other alarm and protection functions.The LCD module can be accessed through the external interface of the main control panel to display relevant information for debugging convenience.At the same time,if the drive module fails,the external LCD can display its failure information.And designed the program to meet the performance of the controller,built the experimental platform,verified the dual redundancy switching experiment of the power board and the debugging experiment of the alarm function of the driver module of the main control board,the experimental results show that the power board can realize the dual redundancy seamless switching;when the driver module of the main control board fails,the external LCD can accurately detect the failure reason.(4)the static and dynamic characteristics of industrial two-dimensional(2D)servo valve and electro-mechanical converter are studied by setting up experimental platform.According to the experimental data of the motor,the frequency width of the stepping motor is 120 Hz,and the step response rising response time is 5.4 Ms.The static and dynamic characteristics of the two-dimensional servo valve are tested.The results show that the hysteresis of the servo valve is 2.1%,the nonlinearity is 1.4%,the leakage is 2.3 L / min at 7 MPa,the frequency width is about 41 Hz,and the rise time of the dynamic step response can reach about 10 ms.In this paper,the dual redundant controller and servo valve are integrated.The synchronous tracking control algorithm of rotor displacement and the closed-loop control algorithm of valve core displacement are used in the control system.The design of the whole controller ensures the completion of the control algorithm,making the power board and the main control board have the functions of dual redundant automatic switching and alarming,and improving the reliability and stability of the whole controller and valve?...