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Enhancement of Wireless Power Transfer Efficiency Using Higher Order Spherical Modes

  • Kim, Yoon Goo (Department of Electrical Engineering and Computer Science, Seoul National University) ;
  • Park, Jongmin (Department of Electrical Engineering and Computer Science, Seoul National University) ;
  • Nam, Sangwook (Department of Electrical Engineering and Computer Science, Seoul National University)
  • Received : 2012.12.27
  • Accepted : 2013.02.21
  • Published : 2013.03.31

Abstract

We derive the Z-parameters for the two coupled antennas used for wireless power transfer under the assumption that the antennas are canonical minimum scattering antennas. Using the Z-parameter and the maximum power transfer efficiency formula, we determine the maximum power transfer efficiency of wireless power transfer systems. The results showed that the maximum power transfer efficiency increases as the mode number or the radiation efficiency increases. To verify the theory, we fabricate and measure two different power transfer systems: one comprises two antennas generating $TM_{01}$ mode; the other comprises two antennas generating $TM_{02}$ mode. When the distance between the centers of the antennas was 30 cm, the maximum power transfer efficiency of the antennas generating the $TM_{02}$ mode increased by 62 % compared to that of the antennas generating the $TM_{01}$ mode.

Keywords

Canonical Minimum Scattering Antenna;Higher Order Mode;Spherical Mode;Wireless Power Transmission

Acknowledgement

Supported by : KCA (Korea Communications Agency)

References

  1. A. Kurs, A. Karalis, R. Moffatt, J. D. Joannopoulos, P. Fisher, and M. Soljacic, "Wireless power transer via strongly coupled magnetic resonances," Science, vol. 317, no. 5834, pp. 83-86, Jul. 2007. https://doi.org/10.1126/science.1143254
  2. A. P. Sample, D. A. Meyer, and J. R. Smith, "Analysis, experimental results, and range adaptation of magnetically coupled resonators for wireless power transfer," IEEE Trans. Ind. Electron., vol. 58, no. 2, pp. 544-554, Feb. 2011. https://doi.org/10.1109/TIE.2010.2046002
  3. I. Awai, T. Komori, "A simple and versatile design method of resonator-coupled wireless power transfer system," in Proc. 2010 International Conference on Communications, Circuits and Systems, pp. 616-620, 2010.
  4. J. Park, Y. Tak, Y. Kim, and S. Nam, "Investigation of adaptive matching methods for near-field wireless power transfer," IEEE Trans. Antennas Propagat., vol. 59, no. 5, pp. 1769-1773, May 2011. https://doi.org/10.1109/TAP.2011.2123061
  5. T. Imura, H. Okabe, and Y. Hori, "Basic experimental study on helical antennas of wireless power transfer for electric vehicles by using magnetic resonant couplings," IEEE Vehicle Power and Propulsion Conference 2009, pp. 936-940, Sep. 2009.
  6. W. K. Kahn, H. Kurss, "Minimum-scattering antennas," IEEE Trans. Antennas Propagat., vol. 13, no.5, pp. 671-675, Sep. 1965. https://doi.org/10.1109/TAP.1965.1138529
  7. P. G. Rogers, "Application of the minimum scatter ing antenna theory to mismatched antennas," IEEE Trans. Antennas Propagat., vol. 34, no. 10, pp. 1223- 1228, Oct. 1986. https://doi.org/10.1109/TAP.1986.1143747
  8. W. Wasylkiwskyj, W. K. Kahn, "Theory of mutual coupling among minimum-scattering antennas," IEEE Trans. Antennas Propagat., vol. 18, no. 2, pp. 204- 216, Mar. 1970. https://doi.org/10.1109/TAP.1970.1139649
  9. FEKO Suite 6.2 User's Manual, EM software & Systems-S.A. (Pty) Ltd., pp. 13-49-13-54.
  10. W. C. Chew, Y. M. Wang, "Efficient ways to compute the vector addition theorem," J. Electromagnet. Waves Appl., vol. 7, no. 5, pp. 651-665, 1993. https://doi.org/10.1163/156939393X00787
  11. J. Lee, S. Nam, "Fundamental aspects of near-field coupling small antennas for wireless power transfer," IEEE Trans. Antennas Propagat., vol. 58, no. 11, pp. 3442-3449, Nov. 2010. https://doi.org/10.1109/TAP.2010.2071330
  12. L. J. Chu, "Physical limitation of omni-directional antennas," J. Appl. Phys., vol. 19, pp. 1163-1175, Dec. 1948. https://doi.org/10.1063/1.1715038
  13. A. Karalis, J. D. Joannopoulos, and M. Soljacic, "Efficient wireless non-radiative mid-range energy transfer," Ann. Phys., vol. 323, no. 1, pp. 34-48, Jan. 2008. https://doi.org/10.1016/j.aop.2007.04.017
  14. J. E. Hansen, Spherical Near-Field Antenna Measurements, London, U.K.: Peter Peregrinus LTd., 1988.
  15. W. Wasylkiwskyj, W. K. Kahn, "Scattering properties and mutual coupling of antennas with prescribed radiation pattern," IEEE Trans. Antennas Propagat., vol. 18, no. 6, pp. 741-752, Nov. 1970. https://doi.org/10.1109/TAP.1970.1139795
  16. S. R. Best, "A comparison of the cylindrical folded helix Q to the Gustafsson limit," in Proc. EuCAP, Berlin, pp. 2554-2557, 2009.
  17. I. Yoon, H. Ling, "Realizing efficient wireless power transfer using small cylindrical helix dipoles," IEEE Antennas and Wireless Propagation Letters, vol. 9, pp. 846-849, 2010. https://doi.org/10.1109/LAWP.2010.2068534
  18. D. M. Pozar, Microwave Engineering, 3rd Ed., New York: John Wiley & Sons, Inc., pp. 548-550, 2005.

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