THE INFLUENCE OF SERVO VALVE SIZE ON THE PERFORMANCE OF A PNEUMATIC POSITION SERVO

摘要

In pneumatics, analog valves have a significant influence on the behaviour of open loop and closed loop systems. The nonlinearities of valves influence steady state accuracy of a system, especially in position servo systems. Valve dynamics influences system steady state accuracy through acceptable control loop gains. Acceptable performance of a pneumatic position servo system is based on a good controller, high flow capacity, and good dynamics of a servo valve. In this paper a pneumatic position servo system with different sizes of servo valves is studied experimentally. Experimental results of the dynamic behaviour and accuracy of a position servo application are shown. The influence of the servo valve size on the movement smoothness and stroke time accuracy is also studied. The influence of the valve size on the general performance of the cylinder drive system is discussed.