Centralized Inverted Decoupling Control

Abstract

Abstract:This paper presents a new methodology of multivariable centralized control based on the structure of inverted decoupling. The method is presented for general n×n processes, obtaining very simple general expressions for the controller elements with a complexity independent of the system size. The possible configurations and realizability conditions are stated. Then, the specification of performance requirements is carried out from simple open loop transfer functions for three common cases. As a particular case, it is shown that the resulting controller elements have PI structure or filtered derivative action plus a time delay when the process elements are given by first order plus time delay systems. Comparisons with other works demonstrate the effectiveness of this methodology through the use of several simulation examples and an experimental lab process.

Inverted decoupling internal model control for square stable multivariable time delay systems

“…This main expression is quite similar to that obtained for the centralized inverted decoupling control in [28]. However, in this method, the desired open-loop transfer matrix L(s) used in [28] is replaced by the desired closed-loop transfer matrix T(s) because of the IMC structure.…”

“…It is based on the structure of centralized inverted decoupling [28] that allows obtaining very simple expressions for controller elements independently of the system size. However, as disadvantage, it cannot be applied to processes with multivariable zeros in the right half plane (RHP) since it results unstable.…”

“…However, in this method, the desired open-loop transfer matrix L(s) used in [28] is replaced by the desired closed-loop transfer matrix T(s) because of the IMC structure. Afterward, the design equations are practically the same of [28].…”

“…However, in this method, the desired open-loop transfer matrix L(s) used in [28] is replaced by the desired closed-loop transfer matrix T(s) because of the IMC structure. Afterward, the design equations are practically the same of [28]. Nevertheless, the tuning procedure using T(s) instead of L(s) allows specifyingthe desired nominal performance in a more direct and easier way than that used in [28].…”

“…Afterward, the design equations are practically the same of [28]. Nevertheless, the tuning procedure using T(s) instead of L(s) allows specifyingthe desired nominal performance in a more direct and easier way than that used in [28]. In the last one, using the classical control feedback scheme,specifications need to be translated to the open-loop transfer functions from the closed-loop requirements.…”