Iterative Adaptive Control Research And The Application Of Electro-hydraulic Servo System

Electro-hydraulic servo system has the advantages of small size, fastresponse, resistance to the load stiffness, etc. and can reproduce the input lawquickly and accurately. Electro-hydraulic servo control system is used in a varietyof control systems that are powerful, precise automatic and with rapid response.Electric hydraulic servo force control system has the advantages of power quality,high reliability, anti-interference ability, fast response, large output, simpleoperation, etc., which have been widely used in a variety of engineering practice.However, electro-hydraulic servo system is a strong non-linear, high-end and ithas large time-varying parameters, external load disturbance and interference withcross-load and other factors, so it is difficult to establish a precise mathematicalmodel, and so the conventional PID controller is difficult to control such systems.Now, because of the actual requirements, performance of force control systembecome increasingly demanding, and needs to reduce the impact of uncertainparameters on the system, which are in urgent need of research and resolve in theelectric hydraulic servo control system.Adaptive control is used to deal with parameter uncertainty problem. Basedon Lyapunov stability theory, we design adaptive laws of parameter to achievestabilization and asymptotic tracking the target trajectory. The adaptive controlhas been widely used in uncertain nonlinear systems because it can effectivelyovercome the impact of the uncertainty on performance of system. The study of iterative learning control has a very important significance todynamical system with control requirements of a strong nonlinear coupling, highposition repeatability, precision tracking, being difficult to model. The biggestadvantage of iterative learning control is that when the control system model iscompletely unknown, we ultimately get accurate tracking of desired trajectorythrough repeated iterations.For force tracking control of problem electro-hydraulic servo control system,an iterative adaptive control is designed, which introduce an adaptive iterativecontroller to resolve the uncertainty and exiting interference of system and todetermine the iteration control parameters to ensure system’s accuracy.Considering the two control, we design controller, combining the advantages oftwo control methods to improve the performance of the non-linear, complex anduncertain control system. Using Matlab verify the effectiveness of program,simulation results show that the program can reduce the tracking error and doresistance to interference to enhance the robustness of the system and improvesystem control accuracy.