Design of a High Order Sliding Mode Controller For Electro-Hydraulic Position Servo System
A design of high-order sliding mode controller for electro-hydraulic position servo system is proposed to improve the con-trol accuracy of electro-hydraulic position servo system.Starting from the structure of electro-hydraulic servo system,its composition results and working process are analyzed.Based on the external input voltage,the dynamic model of the slide valve is obtained.Through the load pressure formed by the pressure difference between the two sub cylinders of the hydraulic cylinder,the flow generat-ed during the dynamic movement of the slide valve is calculated,and the load displacement balance equation is obtained through the load pressure.Then,based on the state parameters of the system such as slide valve displacement,load displacement and input volt-age,The dynamic model of electro-hydraulic servo system is obtained.The general expressions of super screw controller and general-ized super screw controller are introduced.Based on the input voltage error and load displacement error,the sliding surface function of the system is constructed,and the mentor of the sliding surface function is combined with the super screw controller to construct a sliding mode controller based on the super screw controller.In order to improve the convergence speed of the system.Based on the slid-ing mode controller based on super screw controller and with the help of generalized super screw controller,a high-order sliding mode controller is constructed to control the electro-hydraulic position servo system.The experimental results show that the proposed algorithm not only has good response speed,but also has high control accuracy for the electro-hydraulic position servo system.When tracking the target trajectory,the tracking accuracy of the proposed method is 33.11%higher than that of the fuzzy disturbance ob-server method.It shows that the proposed method has good control performance for electro-hydraulic position servo system.
Electro Hydraulic Position Servo SystemHigh Order Sliding Mode ControllerSuper Spiral ControllerGeneralized Hyperspiral ControllerSliding Surface Function