Title
Optimal control of nonlinear switched system in an uncoupled microbial fed-batch fermentation process.
Abstract
The bio-dissimilation of glycerol to 1,3-propanediol (1,3-PD) is a complex bioprocess due to the multiple inhibitions of substrate and products onto the cell growth. In consideration of both the inhibition mechanisms of 3-hydroxypropionaldehyde (3-HPA) and the transport modes of glycerol and 1,3-PD across the cell membrane, we establish a novel switched system which is represented by a ten-dimensional nonlinear dynamical equation containing both extracellular and intracellular environments. The uncoupled microbial fed-batch fermentation process are modeled using the switched system which the glycerol and alkali are respectively poured into. Taking the feeding rates of glycerol and alkali, the switching times and the mode sequence as the control variables, an optimal control model is proposed with the concentration of the terminal time 1,3-PD as performance index. In order to maximize the yield of 1,3-PD, the control parameterization technique and the exact penalty function method are used to solve the considered problem. Numerical results show that under the obtained optimal feeding rates of glycerol and alkali, switching times and mode sequence, the productivity of 1,3-PD at the terminal time is increased significantly compared with previous results.
Year
DOI
Venue
2018
10.1016/j.jfranklin.2018.05.012
Journal of the Franklin Institute
Field
DocType
Volume
Substrate (chemistry),Nonlinear system,Optimal control,Control theory,Glycerol,Control variable,Bioprocess,Fermentation,Mathematics,Penalty method
Journal
355
Issue
ISSN
Citations 
14
0016-0032
0
PageRank 
References 
Authors
0.34
7
4
Name
Order
Citations
PageRank
Teng Niu100.34
Jingang Zhai262.12
Hongchao Yin3224.55
En-Min Feng481.87