Multivariable robust adaptive controller using reduced-order model

Abstract

A general method is developed for predicting the deviation between local and rigorous thermodynamic property models. The method is based on a quadratic error structure. The curvature matrix is updated after each parameter revision. The updating scheme utilizes the observed deviation as a measure for correcting the matrix and thus does not require any additional rigorous model evaluations. A recursive least squares procedure with variable forgetting is adopted for the parameter updating. A local model structure for K-value evaluations is applied in a dynamic simulation model of a batch distillation column. The efficiency and accuracy of the proposed method are tested for two different mixtures; a nearly ideal and a strongly non-ideal mixture.

Keywords

• Local models
• adaptive error estimation
• dynamic simulation