The Research And Application Of Electro-hydraulic Servo Control System

Wave maker is the large laboratory equipment matching ship-model testing basin, which is able to simulate wave in a basin. Wave simulation is very important to ship, water conservancy, port engineering, ocean engineering etc. In order to develop the performance in the basin, enhance the quality and strengthen the oppugn ability of wave maker, this thesis designs the control system of the rocker-flap wave maker irregular wave simulation controlled by electro-hydraulic servo.Firstly, the models of servo amplifier, electro-hydraulic servo valve, valve-controlled hydraulic and pull-pressure sensor are built, and the system model is simplified reasonably, which is on the basis of analyzing the control system of electro-hydraulic servo rocker-flap wave maker. Then, the mathematical model of servo control system was obtained, simulation model of system was derived, and simulation research was done for the system.Secondly, with the study of electro-hydraulic servo system PID control algorithm, the parameters tuning for PID controller were studied by using Ziegler-Nichols method and simulation method. Experimental results verified that this algorithm is effective in the electro-hydraulic servo system.Thirdly, the theory and method of fuzzy controller were studied, this thesis mainly analyzed and designed fuzzy PID parameters tuning control algorithm which is adjusted on-line, and determined the structure of fuzzy PID controller and the fuzzy rules of electro-hydraulic servo system and membership function. Self-tuning rules of PID parameters were given. Simulation experimental results verified that fuzzy PID parameters self-tuning control algorithm had some advantages, such as small overshoot, rapid response, high accuracy, and strong ability of self-adaptation, and so on. The conclusion that this algorithm was better than conventional PID control algorithm was obtained, which reached expected control effect.Finally, the RBF neural network tuning PID control algorithm was discussed. The parameters of PID controller are adjusted on-line based on learning algorithm of neural network, which make the given performance index optimal. The experimental result verifies the feasibility of the control algorithm.