2015 |
Saidi, B.; Amairi, M.; Najar, S.; Aoun, M. Multi-objective optimization based design of fractional PID controller Conférence 2015, (Cited by: 9). Résumé | Liens | BibTeX | Étiquettes: Closed loop systems, Closed-loop behavior, Design, Electric control equipment, Fractional PID, Fractional pid controllers, Fractional-order PID controllers, Frequency bands, Frequency domain analysis, Frequency domains, Frequency specifications, Iso-damping property, Multiobjective optimization, Numerical methods, Phase margins, Proportional control systems, Robustness (control systems), Specifications, Three term control systems @conference{Saidi2015d,This paper deals with robust fractional order PID controller design via numerical multi-objective optimization. The proposed interval-based design scheme uses frequency-domain specifications to ensure a desired closed-loop behavior. By maintaining the desired phase margin quasi-constant in a pre-specified frequency band, it guarantees more robustness to gain uncertainties. This leads to a closed-loop system with an interesting iso-damping property in a more large frequency band than other design methods. A numerical example is presented to show the efficiency of the proposed method and to discuss about the obtained results. © 2015 IEEE. |
Hmed, A. Ben; Amairi, M.; Aoun, M. Stability and resonance conditions of the non-commensurate elementary fractional transfer functions of the second kind Article de journal Dans: Communications in Nonlinear Science and Numerical Simulation, vol. 22, no. 1-3, p. 842 – 865, 2015, (Cited by: 12). Résumé | Liens | BibTeX | Étiquettes: Convergence of numerical methods, Damping, Fractional order, Fractional systems, Frequency domain analysis, Frequency domain curves, Frequency domains, Functions of the second kind, Resonance, Resonance analysis, Resonance condition, Stability, Time domain, Transfer functions @article{BenHmed2015842b,This paper deals with stability and resonance conditions of the non-commensurate elementary fractional transfer function of the second kind. This transfer function is a generalization of the elementary fractional transfer function of the second kind to an arbitrary order. It is written in the canonical form and characterized by a non-commensurate order, a pseudo-damping factor and a natural frequency. Stability and resonance analysis is done in terms of the pseudo-damping factor and the non-commensurate order. Also, an overall study of frequency-domain and time-domain performances of the considered system is done. Therefore many time-domain and frequency-domain curves are presented to help obtaining system parameters for a specified fractional order. Many illustrative examples show the efficiency of this study. Also, an application to the control of a spherical tank is also presented to show the usefulness of this study. © 2014 Elsevier B.V. |
Hmed, A. Ben; Amairi, M.; Aoun, M. Stability and resonance conditions of the non-commensurate elementary fractional transfer functions of the second kind Article de journal Dans: Communications in Nonlinear Science and Numerical Simulation, vol. 22, no. 1-3, p. 842 – 865, 2015, (Cited by: 12). Résumé | Liens | BibTeX | Étiquettes: Convergence of numerical methods, Damping, Fractional order, Fractional systems, Frequency domain analysis, Frequency domain curves, Frequency domains, Functions of the second kind, Resonance, Resonance analysis, Resonance condition, Stability, Time domain, Transfer functions @article{BenHmed2015842c,This paper deals with stability and resonance conditions of the non-commensurate elementary fractional transfer function of the second kind. This transfer function is a generalization of the elementary fractional transfer function of the second kind to an arbitrary order. It is written in the canonical form and characterized by a non-commensurate order, a pseudo-damping factor and a natural frequency. Stability and resonance analysis is done in terms of the pseudo-damping factor and the non-commensurate order. Also, an overall study of frequency-domain and time-domain performances of the considered system is done. Therefore many time-domain and frequency-domain curves are presented to help obtaining system parameters for a specified fractional order. Many illustrative examples show the efficiency of this study. Also, an application to the control of a spherical tank is also presented to show the usefulness of this study. © 2014 Elsevier B.V. |
2014 |
Hmed, A. Ben; Amairi, M.; Najar, S.; Aoun, M. Resonance study of an elementary fractional transfer function of the third kind Conférence 2014, (Cited by: 3). Résumé | Liens | BibTeX | Étiquettes: Calculations, Canonical form, Damping, Damping factors, Differentiation (calculus), Fractional calculus, Frequency domain analysis, Frequency domain curves, Frequency domains, Natural frequencies, Normalized gains, Resonance, Stability condition, Systems analysis, Transfer functions @conference{BenHmed2014c,This work is devoted to the stability and resonance study of the elementary fractional transfer function of the third kind. Some basic properties of this transfer function which is written in the canonical form and characterized by a non commensurate order, a pseudo-damping factor and a natural frequency, are presented. A resonance and stability condition is established numerically in terms of the non commensurate order and the pseudo-damping factor. Many frequency-domain curves are given to determine graphically the pseudo-damping factor and the non commensurate order for a desired normalized gain and normalized resonant frequency. Illustrative examples are presented to show the correctness and the usefulness of these curves. © 2014 IEEE. |
Hmed, A. Ben; Amairi, M.; Najar, S.; Aoun, M. Resonance study of an elementary fractional transfer function of the third kind Conférence 2014, (Cited by: 3). Résumé | Liens | BibTeX | Étiquettes: Calculations, Canonical form, Damping, Damping factors, Differentiation (calculus), Fractional calculus, Frequency domain analysis, Frequency domain curves, Frequency domains, Natural frequencies, Normalized gains, Resonance, Stability condition, Systems analysis, Transfer functions @conference{BenHmed2014e,This work is devoted to the stability and resonance study of the elementary fractional transfer function of the third kind. Some basic properties of this transfer function which is written in the canonical form and characterized by a non commensurate order, a pseudo-damping factor and a natural frequency, are presented. A resonance and stability condition is established numerically in terms of the non commensurate order and the pseudo-damping factor. Many frequency-domain curves are given to determine graphically the pseudo-damping factor and the non commensurate order for a desired normalized gain and normalized resonant frequency. Illustrative examples are presented to show the correctness and the usefulness of these curves. © 2014 IEEE. |
2012 |
Amairi, Messaoud; Aoun, Mohamed; Najar, Slaheddine; Abdelkrim, Mohamed Naceur Guaranteed frequency-domain identification of fractional order systems: Application to a real system Article de journal Dans: International Journal of Modelling, Identification and Control, vol. 17, no. 1, p. 32 – 42, 2012, (Cited by: 20). Résumé | Liens | BibTeX | Étiquettes: Algebra, Constrained optimization, Fractional differentiation, Fractional systems, Frequency domain analysis, Frequency domains, Global optimisation, Global optimization, Identification (control systems), Parameter estimation, Real intervals, Satisfaction problem @article{Amairi201232b,This paper presents a new guaranteed approach for frequency-domain identification of fractional order systems. Estimated parameters (coefficients and differential orders) are expressed as intervals. Then, an interval-based global optimisation algorithm is used to estimate the set of all feasible parameters. It combines the Hansen’s algorithm with forward-backward contractor. The approach is applied to a numerical example as well as to a real electronic system. Copyright © 2012 Inderscience Enterprises Ltd. |