Nonlinear Dynamics

, Volume 29, Issue 1–4, pp 281–296 | Cite as

Analogue Realizations of Fractional-Order Controllers

  • I. Podlubny
  • I. Petráš
  • B. M. Vinagre
  • P. O'Leary
  • Ľ. Dorčák


An approach to the design of analogue circuits, implementingfractional-order controllers, is presented. The suggestedapproach is based on the use of continued fraction expansions;in the case of negative coefficients in a continued fractionexpansion, the use of negative impedance converters is proposed.Several possible methods for obtaining suitable rational appromixationsand continued fraction expansions are discussed. An exampleof realization of a fractional-order Iλ controlleris presented and illustrated by obtained measurements.The suggested approach can be used for the control of veryfast processes, where the use of digital controllers isdifficult or impossible.

fractional calculus fractional differentiation fractional integration fractional-order controller realization 


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Copyright information

© Kluwer Academic Publishers 2002

Authors and Affiliations

  • I. Podlubny
    • 1
  • I. Petráš
    • 1
  • B. M. Vinagre
    • 2
  • P. O'Leary
    • 3
  • Ľ. Dorčák
    • 1
  1. 1.Department of Informatics and Process Control, BERG FacultyTechnical University of KošiceKošiceSlovak Republic
  2. 2.Department of Electronics and Electromechanical Engineering, Industrial Engineering SchoolUniversity of ExtramaduraBadajozSpain
  3. 3.Institute of Automation, Montanuniversität LeobenLeobenAustria

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