Modeling of Airflow Disturbance Force and Feedforward Controller Design in Pneumatic Valves

Pneumatic valves are vital components for controlling flow rates in general industrial applications. To control the flow rate of a valve precisely, this study focuses on controlling the valve body position, primarily determining the flow rate. Fast and precise control of the valve body position requires suppressing disturbance forces caused by air pressure dynamics. The authors address this issue with a feedforward control method by modeling the airflow disturbance force, which is estimated from feedforward inputs obtained through iterative learning control. The developed approach compensates for the airflow disturbance force under various target trajectories and pressure differences. The valve body position and flow rate tracking experiments validate the performance improvements in terms of settling time and overshoot.