Simplified Fractional Order Controller Design Algorithm

• Published in: Mathematics (Basel) Vol. 7; no. 12; p. 1166
• Main Author: Dulf, Eva-Henrietta
• Format: Journal Article
• Language: English
• Published: Basel MDPI AG 02.12.2019
• Subjects: Algorithms; Control systems design; Control theory; Controllers; Damping; Design specifications; Design techniques; Food science; Frequency domain analysis; Mathematical models; Methods; Nonlinear equations; Optimization; Physics; Porous materials; Robustness; Signal processing; Tuning
• ISSN: 2227-7390; 2227-7390
• DOI: 10.3390/math7121166

Classical fractional order controller tuning techniques usually establish the parameters of the controller by solving a system of nonlinear equations resulted from the frequency domain specifications like phase margin, gain crossover frequency, iso-damping property, robustness to uncertainty, etc. In the present paper a novel fractional order generalized optimum method for controller design using frequency domain is presented. The tuning rules are inspired from the symmetrical optimum principles of Kessler. In the first part of the paper are presented the generalized tuning rules of this method. Introducing the fractional order, one more degree of freedom is obtained in design, offering solution for practically any desired closed-loop performance measures. The proposed method has the advantage that takes into account both robustness aspects and desired closed-loop characteristics, using simple tuning-friendly equations. It can be applied to a wide range of process models, from integer order models to fractional order models. Simulation results are given to highlight these advantages.