Research On Position Control Of Servo Motor Pump Controlled Hydraulic Cylinder Using Backstepping Method

A study on the position control of servo motor pump controlled hydraulic cylinder using backstepping method.The pump controlled electro-hydraulic servo system is a highly integrated closed drive unit composed of a bidirectional quantitative pump,servo motor,hydraulic cylinder,etc.Compared with traditional valve control technology,this system has technical advantages such as high integration,high energy efficiency,and high power to weight ratio.However,the pump controlled electro-hydraulic servo system has low control accuracy and poor dynamic performance,and the technical indicators such as response speed,bandwidth,and positioning accuracy of the system need to be improved.Therefore,this article takes the position control strategy of the pump controlled electrohydraulic servo system as the research objective,and the specific research content is as follows:Firstly,establish a mathematical model of the components related to the servo motor and hydraulic system;Next,the pump control position system was analyzed,and a simulation model of the overall system was built using MATLAB/Simulink software platform,providing theoretical guidance for the next step of adopting suitable control strategies.Due to the strong nonlinearity of the pump control system,the control process is inevitably affected by unmodeled dynamics(including time-varying parameters,modeling bias,external disturbances,and variable loads).Traditional PID control and traditional backstepping control are difficult to solve these problems.To this end,a backstepping control method based on unknown dynamic observers is first adopted,which can compensate for the negative effects of unmodeled dynamics,optimize system response performance,and reduce the computational burden on the controller.In order to further improve the above problems,considering that the adaptive backstepping algorithm has strong adaptability to parameter changes,and Sliding mode control has good robustness,this paper uses adaptive backstepping Sliding mode control technology combining the advantages of both.At the same time,in order to improve the engineering practicality of the control strategy and reduce the number of system state variables required by the controller,the equivalent coordinate transformation operation is adopted to convert the state space expression of the pump control system into Brunovsky standard form.Analyze the composition and working principle of the controller in detail,and verify the correctness and effectiveness of the strategy using a system simulation analysis platform.The algorithm designed in this article is applied to the pump controlled electrohydraulic servo equipment.Through experimental verification,both algorithms can achieve high-performance control of the pump control system,which improves the control accuracy and response speed of the system.The experimental results show that the adaptive backstepping Sliding mode control algorithm makes the system have better dynamic and static characteristics.