PNEUMATIC POSITION SERVO SYSTEM USING

 ON/OFF SOLENOID VALVES

Wang Zuwen

（College of Marine Engineering, Dalian Maritime University, Dalian 116026）

Meng Xianchao  Bao Gang

(School of Mechanical and Electrical Engineering,Harbin Institute of Technology, Harbin 150001)

Abstract: A nonlinear model on pneumatic position servo system based on solenoid valves is builted, in which the hysteresis of the solenoid valves is taken into consideration. Further a parametric uncertainty pseudo linear model with time delay is conducted with feedback linearization. As to deal with the robust control problems against parameter uncertainty, noise and load disturbance, quantitative feedback theory (QFT) is employed to shaping the loop transmission, which is expected to own robust stability, robust disturbance rejection and tracking behaviour. The controller adopts the structure of two DOF, which owns an inner feedback loop in order to increase the damping. Friction compensation is also introduced to promote its performance. Finally the experiments based on the controller verify that the servo system embodies robust stability, dynamic performances of accurate and quick response.

Key words: Pneumatic position control  Modelling  Robust control  Quantitative feedback theory (QFT)   Solenoid valve

CLC No: TP271

Received  20031027, received in revised form 20040118