Study On Self-adapting Fuzzy PID Control With Variable Universe In Servo System Of Valve Controlled Asymmetric Cylinder

Because of the simple structure and small spatial volume, valve controlled asymmetric cylinder is widely applied in hydraulic servo system. However, since the valve controlled asymmetric cylinder hydraulic servo is the typical nonlinear system, the conventional PID control is unable to arrive at the ideal control effect. This paper unifies the fuzzy control and the PID control, adjusts the PID parameter through the fuzzy controller real-time, and has realized self-adapting fuzzy PID control with variable universe. We achieve the self-adapting fuzzy PID control with variable universe of valve controlled asymmetric cylinder position servo system in FESTO TP511 hydraulic test-bed, using the seamless integration of LabVIEW and MATLAB software. The thesis has chiefly carried on the following research:(1) To research the operating characteristics of the valve controlled asymmetric cylinder hydraulic servo system, it has established the asymmetric hydraulic cylinder bidirectional movement transfer function model.(2) Self-adapting fuzzy PID control with variable universe is applied in non-linear system with dead zone, and the comparison with the conventional PID control method through the simulation example was carried on.(3) To carry out the data acquisition system design of dual-channel to FESTO TP511 hydraulic test-bed, by using the NI LabVIE software and the PCI6014 data acquisition card.(4) PID parameters were obtained by the integration of Z-N principle and expert experiences. Two kinds of control strategies of conventional PID control and self-adapting fuzzy PID control with variable universe are realized in the test-bed by using LabVIEW and MATLAB software seamless integration.The method of self-adapting fuzzy PID control with variable universe of the valve controlled asymmetric cylinder servo system has been studied systematically in the paper. This method is achieved in the hydraulic servo test-bed by using LabVIEW and MATLAB software seamless integration. The experiment result of hydraulic servo test-bed shows that the proposed method has better control performance. The result of the thesis enriches the achievements of valve controlled asymmetric cylinder hydraulic servo system.