Extension of Modifier Adaptation for Controlled Plants using Static Open-Loop Models

G. FRANÇOIS; S. COSTELLO; A. G. MARCHETTI; D. BONVIN

COMPUTERS AND CHEMICAL ENGINEERING

PERGAMON-ELSEVIER SCIENCE LTD

Lugar: Amsterdam; Año: 2016 vol. 93 p. 361 - 371

0098-1354

Model-based optimization methods suffer from the limited accuracy of the availableprocess models. Because of plant-model mismatch, model-based optimal inputs maybe suboptimal or, worse, unfeasible for the plant. Modifier adaptation (MA) overcomesthis obstacle by incorporating measurements in the optimization framework. However,the standard MA formulation requires that (1) the model satisfies adequacy conditionsand (2) the model and the plant share the same degrees of freedom. In this article, threeextensions of MA to problems where (2) does not hold are proposed. In particular,we consider the case of controlled plants for which the only a model of the open-loopplant is available. These extensions are shown to preserve the ability of MA to convergeto the plant optimum despite disturbances and plant-model mismatch. The proposedmethods are illustrated in simulation for the optimization of a CSTR.