MIMO control performance monitoring using left/right diagonal interactors

Although the minimum variance control (MVC) benchmark is popular for control performance monitoring, the requirement of a general interactor for multivariable processes is equivalent to knowing the Markov parameters, which is inconvenient in practice. To reduce the model requirement of a general interactor, a right diagonal interactor matrix is first used for a class of MIMO processes. Then a solution to the MIMO MVC benchmark is developed using the right diagonal interactor. Next, both the left and right diagonal interactors are integrated to characterize the complex time-delay structure of an extended class of multivariate processes. The factorization of the combined left/right diagonal interactors and the corresponding MVC benchmark estimation are also presented. The advantages of the new approach lie in the reduced a priori process knowledge and the simplified numerical procedures. A number of simulated examples are provided to illustrate the validity and effectiveness of the proposed performance monitoring approach. © 2009 Elsevier Ltd. All rights reserved.