AN IMPROVED ADJUSTABLE ASYMPTOTIC OBSERVER FOR BIOREACTORS

This paper presents an approach to tune the gains of adjustable asymptotic observers on a class of continuous bioreactors. This approach is based on a careful analysis of the error estimation dynamics. The gains calculated with this approach improve the observer performance and guarantee a high convergence rate in the estimation of unmeasured variables with an accurate degree that can be chosen beforehand by the user. This approach was tested through numerical simulations in an anaerobic digestion process for wastewater treatment for the estimation of biomass concentrations, in which the gains obtained actually allowed the adjustable asymptotic observer to estimate the biomass concentrations with absolute precision. In order to show the usefulness of the adjustable asymptotic observer improved with this approach, its performance is compared in the face of the classical asymptotic observer with excellent results.