PI Control of Biomass Concentration for a Continuous-Discrete Bioreactor

This paper proposes the application of a Proportional-Integral (PI) controller for the observer-based regulation of biomass concentration for a continuous-discrete system. An observer is essential to estimate the values of biomass concentration since the controller depends on these measurements. The analysis focuses on the continuous-discrete nature of the system which is represented by a continuous bioreactor system with discrete output measurements. The maximum allowable sampling partition diameter is determined along with the corresponding convergence time. These results are then compared to another work that used a feedback linearising control to achieve biomass regulation. The results obtained with the PI controller proved to be far more superior both in terms of maximum possible sampling time and convergence time. These findings confirmed the satisfactory and improved performance of the proposed observer-based controller.