Unstable 1st order system (bioreactor): stability, equilibrium, transfer function

Antonio Sala, UPV

Difficulty: ** ,       Relevance: PIC,      Duration: 11:33

Materials:    [ Cód.: PIDcontrolAPP1.0.zip ]

Summary:

This video continues with the modelling and analysis of open-loop properties of the bioreactor system whose microscopic statistical model and the averaged macroscopic ordinary differential equation (ODE) were discussed in video [bio1modEN].

In here, we discuss its stability, its equilibrium point (not too useful for the moment being, as it is an unstable equilibrium) and its transfer function representation in the Laplace domain. These will be the basic building blocks that will enable the development of a ‘stabilizing’ controller for achieving a constant biomass population with, say, proportional control (video [bio1cPEN]) or other more refined options in forthcoming videos of this case study.

*Link to my [ whole collection] of videos in English. Link to larger [ Colección completa] in Spanish.

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