Research and Experiment on an Adaptive Feedforward Compensation Composite Control Strategy for an Electro-Hydraulic Servo System

In order to reduce the tracking and response errors of the electro-hydraulic servo system, improve the dynamic response quality of the system, enhance the adaptive ability of the system, and effectively solve the common problems of nonlinear interference and irregular load disturbance in the servo system, a research and experimental scheme for the adaptive feedforward compensation composite control strategy of the electro-hydraulic servo system was proposed. First, the basic structure and mathematical models of the important components of the electro-hydraulic servo test bench were introduced, and the control structure diagrams of torque control and position control were elaborated. The servo working principle of the adaptive composite control based on feedforward compensation was analyzed, and the error function between the theoretical model and the actual model of the motor for motor speed control in the feedforward compensation control process was proposed. Finally, the system was simulated and loaded for testing. Based on the theoretical analysis and experimental results of this study, it can be concluded that if the electro-hydraulic servo system adopts the composite control method of adaptive feedforward compensation, the adaptive ability and disturbance resistance of the system controller can be significantly improved. The experimental comparison results show that the performance is significantly better than that of the system using the traditional PI closed-loop control algorithm and fuzzy PI closed-loop control; The feedforward compensation composite control method can accurately calculate the reference value and adjustment parameters for servo motor speed compensation. The experimental results show that the dynamic response speed of the system is improved by more than 78% compared to the traditional closed-loop control algorithms; In the experiment, the sine response curves of 0.2 Hz and 0.5 Hz were also compared, and it was found that the feedforward compensation composite control system had the best control accuracy and position tracking curve performance, with the smallest error in the actual output value.