Abstract

ISFER, L. A. D.; DA SILVA, G. S.; LENZI, M. K.  and  LENZI, E. K.. Generalization of internal model control loops using fractional calculus. Lat. Am. appl. res. [online]. 2012, vol.42, n.2, pp.149-154. ISSN 0327-0793.

Process control represents an important tool for meeting product quality, process safety and environmental regulation. Different control strategies have been recently proposed in the literature; however, internal model control (IMC) has received great attention. Fractional calculus represents a fast growing field involving non-integer order derivatives. The aim of this work is the application of fractional calculus to develop generalized internal model control loops transfer functions, which is presented in two different approaches: firstly, the process model is considered perfect, i.e., equal to the internal model; secondly, the internal model is described by fractional transfer function. Simulation results showed that the proposed generalization could successfully control an industrial oven and a biochemical reactor described by fractional models, allowing better results when compared to integer order IMC.

Keywords : Process Control; Fractional Differential Equation; Caputo Representation; Internal Model Control; Generalization.