Composed Adaptive Control for a second-order nonlinear model of a biotechnological process

This paper presents a new Composed Adaptive Controller (CAC) for trajectory tracking of a methane fermentation process in stirred tank bio-reactors. The referred biotechnological process is described by a second-order non-linear model based one-stage reaction scheme. The proposed con troller comprises an Algebraic Differential Estimation (ADE) based compensation component and a Recursive Model Free Controller (RMFC) stabilization component which dose not require any knowledge of the physical model parameters. The proposed entire control enables trajectories tracking of a variable set point trajectory and over performs the existing anaerobic digestion control schemes, such as a classical Proportional-Integral-Derivative (PID) control or a nonlinear PI control. Computer simulation examples illustrate the performance and robustness of the proposed approach.