Premium
Interval observer with near optimal adaptation dynamics. Application to the estimation of lipid quota in microalgae
Author(s) -
Mairet Francis,
Moisan Marcelo,
Bernard Olivier
Publication year - 2014
Publication title -
international journal of robust and nonlinear control
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 1.361
H-Index - 106
eISSN - 1099-1239
pISSN - 1049-8923
DOI - 10.1002/rnc.2934
Subject(s) - control theory (sociology) , observer (physics) , interval (graph theory) , computation , mathematical optimization , computer science , mathematics , algorithm , control (management) , artificial intelligence , physics , quantum mechanics , combinatorics
SUMMARY In this paper, the design of an interval observer with an adaptive dynamical gain is presented. The observer is formulated in the framework of robust state estimation of uncertain dynamical systems, where an interval that encloses the unknown state variables is provided. For a specific type of interval observer design, an optimal gain could provide the narrowest interval. Because this gain depends on the (unknown) state, it can however not be determined, and only intervals for this optimal gain can be estimated. Here, we propose a strategy to track, with a high gain observer, the optimal gain together with the computation of its derivative. The observer performance is first illustrated with the simple case of an uncertain bioreactor model. Then, we propose the real case of the estimation of microalgal oil in the framework of biofuel production. The proposed observer design, when applied to experimental data of Isochrysis affinis galbana , appears to be a suitable robust estimation technique. Copyright © 2012 John Wiley & Sons, Ltd.