FUZZY CONTROL OF BAKERS-YEAST FED-BATCH BIOPROCESS - A ROBUSTNESS STUDY

The purpose of the investigation was to determine if, based on the mon itoring of the residual substrate concentration, fuzzy control is an e ffective way of controlling a fermentation process. Various simulation s were made using a knowledge model, first to evaluate the performance of the control for the biomass concentration, and then to analyze how it reacted in the presence of disturbances. Results showed high final productivity and biomass concentration. Despite different disturbance s, as the feeding glucose concentration changed or the temporary subst rate feed-rate increased, the fuzzy controller provided process stabil ity and robustness near the set-point. Moreover, these properties were maintained in the case of noisy measurements.