Optimizing control of uncertain plants with constrained feedback controlled outputs

On-line set-point optimization of technological processes under uncertainty is the subject of the paper for the case with important active constraints on certain process outputs. A miltilayer structure with additional upper l ayer follow-up constraint controller responsible for keeping the output con straints satisfied both in steady states and during transient processes is considered. The integrated system optimization and parameter estimation (IS OPE) method is investigated, i.e. iterative algorithms using an on-line ste ady-state feedback, designed to determine optimum operation of the plant in the presence of inaccurate models and disturbance uncertainties. A new for mulation of the ISOPE method suitable for the considered structure is deriv ed and discussed, followed by a development of an efficient dual-type algor ithm. The algorithms are applied to a case study example-an industrial styr ene production unit consisting of a series of distillation columns. Results of simulation runs for cases with and without errors in the feedback infor mation from the process to the optimizer are reported.