Nonlinear robust control for a photobioreactor in prescence of parametric disturbances

Abstract

This paper presents a robust-PI control applied to a photosynthetic biological system with unknown disturbances presented in its modeling. It is well known that the control of biological process presents several difficulties due to the sensitivity of the biological system parameters, making the control task an interesting problem to solve. An optimal tracking control strategy together with a robust control is proposed to solve the aforementioned problem. The presence of unknown elements and input disturbance were also considered on the control design. In order to prove stability results, Lyapunov techniques were utilized. A new control tuning strategy for systems with stable properties was developed. This control strategy was validated through an experiment using a culture of Spirulina maxima in a continuous photobioreactor for wastewater treatment.