Approximation Techniques

  • Kishore BingiEmail author
  • Rosdiazli Ibrahim
  • Mohd Noh Karsiti
  • Sabo Miya Hassan
  • Vivekananda Rajah Harindran
Part of the Studies in Systems, Decision and Control book series (SSDC, volume 264)


This chapter will focus on practical realization or equivalent circuit implementation of the fractional-order systems and controllers in a finite-dimensional integer-order system. Hence, for achieving the approximated integer-order transfer function of the fractional-order system or controller, a novel curve fitting based approximation techniques for fractional-order differentiator or integrator are developed. The advantage of the techniques is that they are simple, easy to implement and can fit around the desired frequency range. The chapter also provides the MATLAB commands for implementing the developed algorithms. The simulation results in the frequency domain show that the proposed approach produced better parameter approximation for the desired frequency range as compared to Oustaloup, refined Oustaloup, and Matsuda techniques. Furthermore, time domain and stability analysis also validate the frequency domain results.


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Copyright information

© Springer Nature Switzerland AG 2020

Authors and Affiliations

  • Kishore Bingi
    • 1
    Email author
  • Rosdiazli Ibrahim
    • 2
  • Mohd Noh Karsiti
    • 2
  • Sabo Miya Hassan
    • 3
  • Vivekananda Rajah Harindran
    • 4
  1. 1.Institute of Autonomous SystemsUniversiti Teknologi PETRONASPerakMalaysia
  2. 2.Department of Electrical and Electronic EngineeringUniversiti Teknologi PETRONASPerakMalaysia
  3. 3.Department of Electrical and Electronics EngineeringAbubakar Tafawa Balewa UniversityBauchiNigeria
  4. 4.Instrumentation and ControlPETRONAS Group Technical SolutionsPetaling JayaMalaysia

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