The Value of Simple Multivariable and Nonlinear Models in Process Control

Simple conceptual or mathematical models have always been used in design of linear SISO process controllers. On the other hand the design of nonlinear or MIMO controllers has always been perceived as requiring a detailed dynamic model. This communication aims to show that, the use of simple models, can drastically affect the design of such controllers by suggesting a design framework that centers around the extensive variable of the process instead of the intensive one that are usually measured.