A new approach to averaging level control

In this paper, a new simple algorithm for averaging level control is presented. The proposed algorithm is based on the use of a static nonlinear controller to improve the input flow filtering by reducing the slope of the controller around the average input flow. In order to adapt the controller to changes in the average input flow, a low-pass filtered value of the estimated input flow is used to update the nonlinear function that defines the static controller. The stability of the closed loop is demonstrated, and the validity of the proposed strategy is tested in simulations and on a real oil refinery process.