A robust-adaptive control strategy for a continuous alcoholic fermentation process

This work presents the design and the analysis of a robust-adaptive control algorithm for an alcoholic fermentation process that takes place inside a Continuous Stirred Tank Reactor (CSTR). Initially, an adaptive controller is obtained by mixing a linearizing controller with a novel parameter estimator which is used for reconstruction of unknown kinetics. Afterwards, by considering the realistic assumption that the reaction kinetics are unknown, time-varying and moreover the influent flow rates are uncertain and time-varying (although with known lower and upper bounds), a new robust-adaptive control scheme is developed by mixing an exact linearizing controller with a parameter interval estimator capable to estimate the kinetics lower and upper bounds. The performance of the designed controllers is illustrated by computer simulations.