Abstract
Optimal control profiles as calculated with two control algorithms, singular approximation and minimum principle, are compared in this article. Switching points were determined using the singular approximation by mathematical calculation. The optimal growth rate was calculated using minimum principle. With an increased number of switching points, the calculated optimal control profiles approached the theoretical optimal control profile as calculated using the minimum principle. With three switching times, the product concentration approached 96% of the theoretical optimal control profile. From these results, optimal control can be achieved with more than a three-switching-point approximation.
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Abbreviations
- H :
-
Hamiltonian
- P :
-
product concentration (g/L)
- t :
-
time (d)
- t f :
-
final time (d)
- V :
-
fermentor volume (L)
- X :
-
cell concentration (g/L)
- X 1 :
-
cell mass (g)
- X 2 :
-
product (g)
- λ:
-
adjoint vector
- μ:
-
specific growth rate (1/d)
- π:
-
specific production rate (1/d)
- max:
-
maximum
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Lee, JH. Optimization of secondary metabolite production using singular approximation and minimum principle. Appl Biochem Biotechnol 95, 113–124 (2001). https://doi.org/10.1385/ABAB:95:2:113
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DOI: https://doi.org/10.1385/ABAB:95:2:113