Robust H∞ control of a class of continuous fermentation processes

This paper deals with the H-infinity control of a class of fermentation processes that are described by an unstructured fermentation process model. For a given dilution rate, an optimal controller has been developed which guarantees the so-called L-2-gain from the disturbance to the error between the substrate concentration and the desired optimal substrate concentration to be no larger than a prescribed value in lieu of the system's uncertainties. The disturbance affecting the system's dynamics comes from the residue of the feed substrate concentration, external noise, and unmodelled dynamics. It is stressed that this optimal controller requires only the substrate concentration to be measurable. (C) 1999 Elsevier Science Ltd. All rights reserved.