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Indexed by:Journal Papers

Date of Publication:2015-10-01

Journal:JOURNAL OF OPTIMIZATION THEORY AND APPLICATIONS

Included Journals:SCIE、Scopus

Volume:167

Issue:1

Page Number:342-362

ISSN No.:0022-3239

Key Words:Nonlinear dynamic system; Microbial batch culture; Robust control; System sensitivity

Abstract:This paper considers the microbial batch culture process for producing 1,3-propanediol (1,3-PD) via glycerol fermentation. Our goal was to design an optimal control scheme for this process, with the aim of balancing two (perhaps competing) objectives: (i) the process should yield a sufficiently high concentration of 1,3-PD at the terminal time and (ii) the process should be robust with respect to changes in various uncertain system parameters. Accordingly, we pose an optimal control problem, in which both process yield and process sensitivity are considered in the objective function. The control variables in this problem are the terminal time of the batch culture process and the initial concentrations of biomass and glycerol in the batch reactor. By performing a time-scaling transformation and introducing an auxiliary dynamic system to calculate process sensitivity, we obtain an equivalent optimal control problem in standard form. We then develop a particle swarm optimization algorithm for solving this equivalent problem. Finally, we explore the trade-off between process efficiency and process robustness via numerical simulations.