Sliding Mode Control of Digital Directional Valve Drive System Based on New Approach Rate

Abstract

As an important development direction of hydraulic control components, static and dynamic properties of the spool drive mechanism determine the dynamic and static performance of the digital valve. For the study, permanent magnet synchronous motor and screw nut unit are used as the core drive mechanism for digital directional valve. To solve the practical problems that permanent magnet synchronous motor can not meet the performance requirements of digital directional valve in terms of spool position control accuracy and response speed, a sliding mode variable structure control algorithm with improved approach rate is registered, then the controller is devised and applied to position high-performance control of spool drive mechanism of digital directional valve. The simulation platform of digital directional valve drive system is built by MATLAB/Simulink software and compared with the control effect of traditional PI control algorithm. The emulation results show that can improved approach rate sliding-mode controller can be good for raise the speed of response and reinforce the trueness of the dynamic tracking accuracy of the system, has good dynamic response characteristics, and satisfies the performance requirements of digital directional valve.