Nonlinear indirect adaptive control of a Fed-batch fermentation Bioprocess

This paper addresses the design of an adaptive control strategy for an alcoholic fermentation bioprocess, which takes place inside of a Fed-batch Bioreactor (FBB). This bioprocess is highly nonlinear, some state variables are not measurable and moreover the reaction kinetics is not perfectly known. The kinetic parameters are estimated by using a high-gain nonlinear estimator. An asymptotic state observer is derived so as to provide the unavailable states necessary to the kinetics estimator. Finally, the indirect adaptive control law is designed by combining a linearizing controller with the nonlinear observers. Several numerical simulations are performed, in order to test the proposed nonlinear adaptive control strategy.