ON THE EXTREMUM-SEEKING CONTROL DESIGN AND APPLICATION FOR ANAEROBIC DIGESTION PROCESSES

Abstract

The paper deals with the optimization of nonlinear systems by using Extremum Seeking Control (ESC) without any prior knowledge of the system model. An Extend Kalman Filter based Extremum Seeking Control (EKF based ESC) is proposed, which can make the amplitude of perturbation signal variable and ensure convergence to zero, i.e. without steady-state oscillation. The proposed ESC algorithm makes also possible to obtain more accurate gradient estimate and more rapid ESC convergence. The proposed EKF based ESC algorithm is applied to a fifth-order model of anaerobic digestion process and its performances are compared with the performances of the classical ESC algorithm. Key Words: ESC, EKF, steady state oscillation, anaerobic digestion processes