State Estimator Based Feedback Control for a Metering Poppet Valve System

In this work, a feedback linearization controller (FLC) is developed for a unique electro hydraulic flow control valve. The valve is a unique design developed at the University of Missouri with two stages: a pilot stage and a main stage which both employ poppet valves rather than more common spool valves. The controller is applied with the aid of the Extended Kalman Filter (EKF). The EKF supplies all the state estimates which are necessary for the installation of the controller in an actual physical system. The simulation results show that the FLC tracks the reference signal accurately and with a fast response. It is also shown that the controller can achieve the tracking task under different operating conditions and has ability to reject system disturbances. From the robustness test, it is shown that an accurate model is necessary for the feedback linearization controller to work.