Research on Electro-Hydraulic Force Servo Control System Based on Specialist PID Control Strategy

There is flexibility load in the electro-hydraulic force servo control system researched in this paper, and it results in that there is a lower oscillation frequency secondary differential element in radical of the transmit function of the system. The flexibility load and the secondary differential element seriously impact the bandwidth of the system and let the bandwidth rise difficultly, and that the flexibility load and the secondary differential element make the system oscillation even instability easily. Aiming at this special characteristic and the smaller system gain characteristic of the electrohydraulic force servo control system, the specialist PID control theory applied to the electro-hydraulic force servo control system which is the typical nonlinear system. The mathematic model of the system is built and the simulation and the experiment research is finished in the work of this paper, at the same time, the author of this paper compares the control result of the new controller designed according to the specialist PID control theory with the control result of traditional PID controller. The simulation and the experiment results indicate that the new controller designed according to the specialist PID control theory not only enlarge the bandwidth of system, improve the accuracy, reduce control error, but also accelerate the response speed obviously, increase the dynamic property of the system.