Output regulation of a class of unstructured models of continuous bioreactors: steady-state approaches

Abstract

This article deals with the output regulation of continuous bioreactors in the face of constant disturbances and inverse dynamics. Nonlinear controllers developed on the basis of approximate equilibrium manifolds can almost attenuate measurable or unmeasurable disturbances on the output. This nonlinear feed-forward/feedback control framework without any tuning parameters can be directly implemented to strictly nonlinear systems. Under dynamic actuator constraints and the availability of only output signals for use in the control law, closed-loop simulations demonstrate that the proposed control techniques are superior to a nonlinear PI control scheme based on the identified Hammerstein model.

Output Regulation of Self-Oscillating Biosystems: Model-Based Proportional−Integral/Proportional−Integral−Derivative (PI/PID) Control Approaches

“…Unfortunately, the analytical equilibrium manifolds cannot be obtained directly, because of implicit, disturbance-dependent nonlinear functions. In reference to the recent result in Wu and Huang, an “approximate” equilibrium manifold is calculated by solving the number of reduced nonlinear algebraic equations: where z̄ i ∈ ℝ n and d i ∈ W . Note that d i represents a known constant as a set of discrete points.…”

Output feedback finite-time control for a bioreactor system based on a finite-time stable observer

“…Based on these two approaches, a hybrid sliding mode control method is proposed. For non-minimum-phase bioreactor systems with disturbances, output regulation (Wu and Huang, 2003) is investigated. A type-2 fuzzy logic control is proposed for a continuous bioreactor characterized by bifurcations (Galluzzo and Cosenza, 2009).…”