Tuning algorithms for fractional order internal model controllers for time delay processes. Issue 3 (3rd March 2016)

• Record Type: Journal Article
• Authors: Muresan, Cristina I.; Dutta, Abhishek; Dulf, Eva H.; Pinar, Zehra; Maxim, Anca; Ionescu, Clara M.
• Is Part Of: International journal of control. Volume 89:Issue 3(2016)
• Page Start: 579
• Page End: 593
• Publication Date: 2016-03-03
• Subjects: Control design -- internal model control -- fractional calculus -- robustness -- time delays -- multivariable process -- experimental results; Automatic control -- Periodicals; Electronic journals; 629.8
• DOI: 10.1080/00207179.2015.1086027
• Languages: English
• ISSNs: 0020-7179

Abstract

ABSTRACT: This paper presents two tuning algorithms for fractional-order internal model control (IMC) controllers for time delay processes. The two tuning algorithms are based on two specific closed-loop control configurations: the IMC control structure and the Smith predictor structure. In the latter, the equivalency between IMC and Smith predictor control structures is used to tune a fractional-order IMC controller as the primary controller of the Smith predictor structure. Fractional-order IMC controllers are designed in both cases in order to enhance the closed-loop performance and robustness of classical integer order IMC controllers. The tuning procedures are exemplified for both single-input-single-output as well as multivariable processes, described by first-order and second-order transfer functions with time delays. Different numerical examples are provided, including a general multivariable time delay process. Integer order IMC controllers are designed in each case, as well as fractional-order IMC controllers. The simulation results show that the proposed fractional-order IMC controller ensures an increased robustness to modelling uncertainties. Experimental results are also provided, for the design of a multivariable fractional-order IMC controller in a Smith predictor structure for a quadruple-tank system.