Optimal control of a batch bioreactor: a study on the use of an imperfect model

Abstract This paper presents a numerical study on the performance degradation of a batch bioreactor optimal control strategy when the model used to compute such strategy shows wide variations from the real process. The optimal control was computed using a model that, when exposed to large variations of the control inputs, presents large departures from real process behavior. An improved model based on published experiments was proposed. A new optimal policy was calculated and the behavior of this model when controlled with the earlier policy was studied. Although the earlier control showed a performance degradation with respect to the real optimal control, degradation was modest, and the results are superior to these obtained with other control strategies.

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