Compensation of Pressure Dependent Disturbance: Poppet Position Control in a Pneumatic Valve

Pneumatic valves are key components for controlling mass flow rates in general industrial applications. However, they have several nonlinearities such as dead zone and airflow force, making precise control of mass flow rates challenging. Since the poppet position mostly determines the mass flow rate of a valve, this study employs a new valve with an internal position sensor. The authors propose a data-driven feedforward control method to precisely control the poppet position at arbitrary pressure differences by estimating air disturbance force including airflow force. The developed approach compensates for the air disturbance force to the poppet position and enables fast movement without overshooting. The performance improvement is experimentally validated in the poppet position tracking experiments.