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Rational approximation of fractional order systems by vector fitting method

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  • Control Theory and Applications
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Abstract

A novel method for approximating fractional order systems is presented. Vector fitting is involved in this method. As the basis of approximation of fractional order systems, approximation of fractional order operators is mostly achieved by curve fitting in frequency domain, such as the well-known Oustaloup’s method. However, these methods have several serious defects in principle. A new perspective based on system identification is adopted to deal with approximation of fractional order operators in this paper. Moreover, nonzero initial condition for approximating fractional order systems is considered. And the proposed assignment of initial values for the Caputo case offers an effective solution for the simulation with nonzero initial condition. Finally, numerical examples are given to verify the efficiency of the proposed method.

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References

  1. C. A. Monje, Y. Q. Chen, B. M. Vinagre, D. Y. Xue, and V. Feliu, Fractional-order Systems and Controls: Fundamentals and Applications, Springer, London, 2010.

    Book  MATH  Google Scholar 

  2. T. Kaczorek, Selected Problems of Fractional Systems Theory, Springer, Berlin, 2011.

    Book  MATH  Google Scholar 

  3. M. L. Du, Z. H. Wang, and H. Y. Hu, “Measuring memory with the order of fractional derivative,” Scientific reports, 3:3431, pp. 1–3, 2013.

    Google Scholar 

  4. T. Kaczorek and K. Rogowski, Fractional Linear Systems and Electrical Circuits, Springer, Cham, 2014.

    MATH  Google Scholar 

  5. T. T. Hartley and C. F. Lorenzo, “Fractional-order system identification based on continuous order-distributions,” Signal Processing, vol. 83, no. 11, pp. 2287–2300, 2003.

    Article  MATH  Google Scholar 

  6. S. Victor, R. Malti, H. Garnier, and A. Oustaloup, “Parameter and differentiation order estimation in fractional models,” Automatica, vol. 49, no. 4, pp. 926–935, 2013.

    Article  MathSciNet  MATH  Google Scholar 

  7. J. G. Lu, Y. Q. Chen, “Robust stability and stabilization of fractional-order interval systems with the fractional order: the 0 <α < 1 case,” IEEE Transactions on Automatic Control, vol. 55, no. 1, pp. 152–158, 2010.

    Article  MathSciNet  Google Scholar 

  8. Y. Luo and Y. Q. Chen, “Stabilizing and robust fractional order PI controller synthesis for first order plus time delay systems,” Automatica, vol. 48, no. 9, pp. 2159–2167, 2012.

    Article  MathSciNet  MATH  Google Scholar 

  9. Y. H. Wei, Y. Q. Chen, S. Liang, and Y. Wang, “A novel algorithm on adaptive backstepping control of fractional order systems,” Neurocomputing, vol. 165, pp. 395–402, 2015.

    Article  Google Scholar 

  10. A. Oustaloup, Diversity and Non-integer Differentiation for System Dynamics, Wiley-ISTE, London, 2014.

    Book  MATH  Google Scholar 

  11. Z. Li, L. Liu, S. Dehghan, Y. Q. Chen, and D. Y. Xue, “A review and evaluation of numerical tools for fractional calculus and fractional order controls,” International Journal of Control, Doi: 10.1080/00207179.2015.1124290, 2016.

    Google Scholar 

  12. G. E. Carlson, Simulation on the Fractional Derivative Operator √s and the Fractional Integral Operator √s, Kansas State University, Manhattan, 1960.

    Google Scholar 

  13. S. D. Roy, “On the realization of a constant-argument immittance or fractional operator,” IEEE Transactions on Circuit Theory, vol. 14, no. 3, pp. 264–274, 1967.

    Article  Google Scholar 

  14. A. Oustaloup, F. Levron, B. Mathieu, and F. M. Nanot, “Frequency-band complex noninteger differentiator: characterization and synthesis,” IEEE Transactions on Circuits and Systems I: Fundamental Theory and Applications, vol. 47, no. 1, pp. 25–40, 2000.

    Article  Google Scholar 

  15. D. Y. Xue, C. N. Zhao, and Y. Q. Chen, “A modified approximation method of fractional order system,” Proceedings of the 2006 IEEE International Conference Mechatronics and Automation, Luoyang, China, pp. 1043–1048, 2006.

    Chapter  Google Scholar 

  16. M. Li and D. Y. Xue, “A new approximation algorithm of fractional order system models based optimization,” Journal of Dynamic Systems, Measurement, and Control, vol. 134, no. 4, pp. 44–50, 2012.

    Article  Google Scholar 

  17. Y. H. Wei, Q. Gao, C. Peng, and Y. Wang, “A rational approximate method to fractional order systems,” International Journal of Control, Automation and Systems, vol. 12, no. 6, pp. 1180–1186, 2014.

    Article  Google Scholar 

  18. W. Krajewski and U. Viaro, “A method for the integerorder approximation of fractional-order systems,” Journal of the Franklin Institute, vol. 351, no. 1, pp. 555–564, 2014.

    Article  MATH  Google Scholar 

  19. S. Liang, C. Peng, Z. Liao, and Y. Wang, “State space approximation for general fractional order dynamic systems,” International Journal of System Science, vol. 45, no. 10, pp. 2203–2212, 2014.

    Article  MathSciNet  MATH  Google Scholar 

  20. B. Gustavsen and A. Semlyen, “Rational approximation of frequency domain responses by vector fitting,” IEEE Transactions on Power Delivery, vol. 14, no. 3, pp. 1052–1061, 1999.

    Article  Google Scholar 

  21. J. C. Trigeassoua, N. Maamrib, J. Sabatiera, and A. Oustaloup, “Transients of fractional-order integrator and derivatives,” Signal, Image and Video Processing, vol. 6, no. 3, pp. 359–372, 2012.

    Article  Google Scholar 

  22. G. Montseny, “Diffusive representation of pseudodifferential time-operators,” Proceedings of Fractional Differential Systems: Models, Methods and Applications, Toulouse, France, pp. 159–175, 1998.

    Google Scholar 

  23. J. C. Trigeassoua, N. Maamrib, J. Sabatiera, and A. Oustaloup, “State variables and transients of fractional order differential systems,” Computers & Mathematics with Applications, vol. 64, no. 10, pp. 3117–3140, 2012.

    Article  MathSciNet  Google Scholar 

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Correspondence to Yong Wang.

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Recommended by Associate Editor Choon Ki Ahn under the direction of Editor Duk-Sun Shim. This work is supported by the National Natural Science Foundation of China (No.61573332, No.61601431) and the Fundamental Research Funds for the Central Universities (No.WK2100100028).

Bin Du received his B.Eng. degree in Electrical Engineering from Nanjing University of Aeronautics and Astronautics in 2014. He is currently a Master candidate of Automation at University of Science and Technology of China. His research interests include fractional order systems nonzero initial condition and system identification.

Yiheng Wei received his Ph.D. degree in Automation from University of Science and Technology of China in 2015. He has been with University of Science and Technology of China since 2015, as a postdoctoral research associate. His research interests include fractional order systems identification, analysis and synthesis.

Shu Liang received his Ph.D. degree in Automation from University of Science and Technology of China in 2015. His research interests include fractional order systems and robust control.

Yong Wang received the B.Eng. degree in Automatic from the University of Science and Technology of China in 1982 and his M.Eng. and Ph.D. degrees in navigation, guidance, and control from Nanjing Aeronautical Institute, in 1985 and 1999 respectively. He has been with the Department of Automation, University of Science and Technology of China since 2001, where he is currently a Professor. He has published more than 260 refereed journal and conference papers. His research interests include active vibration control, vehicle guidance and control and fractional order dynamic and control.

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Du, B., Wei, Y., Liang, S. et al. Rational approximation of fractional order systems by vector fitting method. Int. J. Control Autom. Syst. 15, 186–195 (2017). https://doi.org/10.1007/s12555-015-0351-1

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  • DOI: https://doi.org/10.1007/s12555-015-0351-1

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