Abstract:At present, the return landing of the engine valve is not stable, which results in a large jump range. Therefore, the control system of the electrohydraulic actuator was designed, and the movement displacement and speed of the valve were simulated. The driving plan of the electrohydraulic valve was established, and the driving mode of the hydraulic actuator was analyzed. The change process of the position of the servo valve core in three different states was given, and the expression of the change of the valve hydraulic drive was obtained. The neural network PID control system and the filter principle of tracking differentiator were analyzed, and the combined control system was designed. In order to verify the error of valve movement displacement and speed under different interference conditions, it was simulated and verified by using MATLAB software. The simulation results show that under the condition of the same external interference, the maximum errors of the valve movement displacement and speed are larger and the error jump amplitudes are larger when the traditional PID control system is adopted; the maximum errors of the valve movement displacement and speed are smaller and the error jump amplitudes are smaller when the combined control system is adopted. Combined control system can suppress the external interference, and the valve return landing is relatively stable, thus the output errors of the valve displacement and speed are reduced.