Nonlinear PI controllers for continuous bioreactors using population balance models.

Wei Wu; Haw-Yuan Chang

doi:10.1007/s00449-005-0022-3

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Nonlinear PI controllers for continuous bioreactors using population balance models.

Wei Wu·Haw-Yuan Chang

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Abstract

Continuous bioreactors are critical unit operations in many biological systems, but the unique modeling is very complicated due to the underlying biochemical reactions and the distributed properties of cell population. The scope of this paper considers a popular modeling method for microbial cell cultures by population balance equation models, and the control objective aims to attenuate undesired oscillations appeared in the nonlinear distributed parameter system. In view of pursuing the popular/practical control configuration and the lack of on-line sensors, an approximate technique by exploiting the "pseudo-steady-state" approach constructs a simple nonlinear control model. Through an off-line estimation mechanism for the system having self-oscillating behavior, two kinds of nonlinear PI configurations are developed. Closed-loop simulation results have confirmed that the regulatory and tracking performances of the control system proposed are good.

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Adaptation, Physiological Algorithms Bacterial Physiological Phenomena Bioreactors Cell Culture Techniques Cell Proliferation Computer Simulation Feedback Models, Biological Nonlinear Dynamics Population Dynamics Journal Article Research Support, Non-U.S. Gov't

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Wei Wu, Haw-Yuan Chang. 2005-10-28. Nonlinear PI controllers for continuous bioreactors using population balance models.. https://doi.org/10.1007/s00449-005-0022-3

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