Aplication of the Internal Model Control Method to a Simulated Dryer Section of a Paper Mill

DRYER SECTION OF A PAPER MILL M. Berrada, P. Radziszewski, M. E. Elkadiri Department of Applied Sciences, Université du Québec en Abitibi Témiscamingue, Rouyn Noranda, Québec, Canada, J9X 5E4 ABSTRACT This paper presents an application of the Internal Model Controller (IMC) to the heat exchange in a dryer section of paper product industry. A quantitative discussion on numerical control of multivariable systems with use of reference-models is presented: the IMC design and application to multivariable systems are illustrated. The application of the IMC to a dryer section is studied, and some simulation test results are presented and discussed in the numerical control manner. The state model for the drying paper is based on the balance equations written for the steam, the paper, the wall of cylindrical heater, and the moisture. A methodology in developing the dynamic model is presented. 1. Controller design In previous articles [15, 16], the method Internal Model Controller (IMC) has been largely explained. Here is presented the essential calculation of this method. A general diagram of control structure is illustrated in figure 1. All the models are in state-space form. The process is represented by two models: the Internal Model (M) which is the relation between manipulated inputs and outputs, and the Measurable Perturbations Model (P) which is the relation between the measurable perturbations (measurable inputs that can't be manipulated) and outputs.