volume | PIER Journals

Abstract

Magnetic resonant wireless power transfer (WPT) is an emerging technology that may create new applications for wireless power charging. However, low efficiency resulting from resonant frequency drift is a main obstructing factor for promoting this technology. In this paper, a novel method of coordinating the operating frequency and load resistor is proposed to prevent frequency drift. The system efficiency and input impedance are obtained by solving the system equivalent equations. In addition, the new resonant frequencies can be obtained by solving the input impedance equations. Moreover, the process of the coordination method is illustrated. When resonant frequency drift occurs, the system can now operate at the resonant state, and the efficiency can be improved by using the proposed method. The WPT system via magnetic resonance coupling is designed. Simulated and experimental results validating the proposed method are given.

1. Parise, M. and G. Antonini, "On the inductive coupling between two parallel thin-wire circular loop antennas," IEEE Transactions on Electromagnetic Compatibility, Vol. 60, No. 6, 1865-1872, 2018.
doi:10.1109/TEMC.2018.2790265

2. Shinohara, N., "The wireless power transmission: inductive coupling, radio wave, and resonance coupling," Wiley Interdisciplinary Reviews-Energy and Environment, Vol. 1, No. 3, 337-346, 2012.
doi:10.1002/wene.43

3. Kurs, A., A. Karalis, R. Moffatt, et al. "Wireless power transfer via strongly coupled magnetic resonances," Science, Vol. 317, No. 6, 83-86, 2007.
doi:10.1126/science.1143254

4. Karalis, A., J. D. Joannopoulos, and M. Soljačić, "Efficient wireless non-radiative mid-range energy transfer," Annals of Physics, Vol. 323, No. 1, 34-48, 2008.
doi:10.1016/j.aop.2007.04.017

5. Hamam, R. E., A. Karalis, J. Joannopoulos, et al. "Efficient weakly-radiative wireless energy transfer: An EIT-like approach," Annals of Physics, Vol. 324, No. 8, 1783-1795, 2009.
doi:10.1016/j.aop.2009.05.005

6. Jaegue, S., S. Seungyong, K. Yangsu, et al. "Design and implementation of shaped magnetic-resonance-based wireless power transfer system for roadway-powered moving electric vehicles," IEEE Transactions on Industrial Electronics, Vol. 61, No. 3, 1179-1192, 2014.
doi:10.1109/TIE.2013.2258294

7. RamRakhyani, A. K., S. Mirabbasi, and M. Chiao, "Design and optimization of resonance-based efficient wireless power delivery systems for biomedical implants," IEEE Transactions on Biomedical Circuits and Systems, Vol. 5, No. 1, 48-63, 2011.
doi:10.1109/TBCAS.2010.2072782

8. Choi, S. Y., B. W. Gu, S. W. Lee, et al. "Generalized active EMF cancel methods for wireless electric vehicles," IEEE Transactions on Power Electronics, Vol. 29, No. 11, 5770-5783, 2014.
doi:10.1109/TPEL.2013.2295094

9. Chen, L., S. Liu, Y. Zhou, et al. "An optimizable circuit structure for high-efficiency wireless power transfer," IEEE Transactions on Industrial Electronics, Vol. 6, No. 1, 339-349, 2013.
doi:10.1109/TIE.2011.2179275

10. Cheon, S., Y.-H. Kim, S.-Y. Kang, et al. "Circuit-model-based analysis of a wireless energy-transfer system via coupled magnetic resonances," IEEE Transactions on Industrial Electronics, Vol. 58, No. 7, 2906-2914, 2011.
doi:10.1109/TIE.2010.2072893

11. Jinwook, D. K. and Y. Park, "Analysis of capacitive impedance matching networks for simultaneous wireless power transfer to multiple devices," IEEE Transactions on Industrial Electronics, Vol. 62, No. 5, 2807-2813, 2014.

12. Dukju, A. and H. Songcheol, "A transmitter or a receiver consisting of two strongly coupled resonators for enhanced resonant coupling in wireless power transfer," IEEE Transactions on Industrial Electronics, Vol. 61, No. 3, 1193-1203, 2014.
doi:10.1109/TIE.2013.2257151

13. Dukju, A. and H. Songcheol, "A study on magnetic field repeater in wireless power transfer," IEEE Transactions on Industrial Electronics, Vol. 60, No. 1, 360-371, 2013.

14. Kiani, M., U.-M. Jow, and M. Ghovanloo, "Design and optimization of a 3-coil inductive link for efficient wireless power transmission," IEEE Transactions on Biomedical Circuits and Systems, Vol. 5, No. 6, 579-591, 2011.
doi:10.1109/TBCAS.2011.2158431

15. Kim, J., H.-C. Son, K.-H. Kim, et al. "Efficiency analysis of magnetic resonance wireless power transfer with intermediate resonant coil," IEEE Antennas and Wireless Propagation Letters, Vol. 10, 389-392, 2011.

16. Lee, C. K., W. Zhong, and S. Hui, "Effects of magnetic coupling of nonadjacent resonators on wireless power domino-resonator systems," IEEE Transactions on Power Electronics, Vol. 27, No. 4, 1905-1916, 2012.
doi:10.1109/TPEL.2011.2169460

17. Huang, S. D., Z. Q. Li, and Y. Li, "Transfer efficiency analysis of magnetic resonance wireless power transfer with intermediate resonant coil," Journal of Applied Physics, Vol. 115, No. 17, 1-3, 2014.

18. Casanova, J. J., Z. N. Low, and J. S. Lin, "A loosely coupled planar wireless power system for multiple receivers," IEEE Transactions on Industrial Electronics, Vol. 56, No. 8, 3060-3068, 2009.
doi:10.1109/TIE.2009.2023633

19. Xiu, Z., S. L. Ho, and W. N. Fu, "Quantitative analysis of a wireless power transfer cell with planar spiral structures," IEEE Transactions on Magnetics, Vol. 47, No. 10, 3200-3203, 2011.
doi:10.1109/TMAG.2011.2147768

20. Yang, Z., L. Wentai, and E. Basham, "Inductor modeling in wireless links for implantable electronics," IEEE Transactions on Magnetics, Vol. 43, No. 10, 3851-3860, 2007.
doi:10.1109/TMAG.2007.904189

21. Kim, N. Y., K. Y. Kim, J. Choi, et al. "Adaptive frequency with power-level tracking system for efficient magnetic resonance wireless power transfer," Electronics Letters, Vol. 48, No. 8, 452-454, 2012.
doi:10.1049/el.2012.0580

22. Sample, A. P., D. A. Meyer, and J. R. Smith, "Analysis, experimental results, and range adaptation of magnetically coupled resonators for wireless power transfer," IEEE Transactions on Industrial Electronics, Vol. 58, No. 2, 544-554, 2011.
doi:10.1109/TIE.2010.2046002

23. Duong, T. P. and J.-W. Lee, "Experimental results of high-efficiency resonant coupling wireless power transfer using a variable coupling method," IEEE Microwave and Wireless Components Letters, Vol. 21, No. 8, 442-444, 2011.
doi:10.1109/LMWC.2011.2160163

24. Juseop, L., L. Yong-Seok, Y. Woo-Jin, et al. "Wireless power transfer system adaptive to change in coil separation," IEEE Transactions on Antennas and Propagation, Vol. 62, No. 2, 889-897, 2014.
doi:10.1109/TAP.2013.2290795

25. Minfan, F., Y. He, Z. Xinen, et al. "Analysis and tracking of optimal load in wireless power transfer systems," IEEE Transactions on Power Electronics, Vol. 30, No. 7, 3952-3963, 2015.
doi:10.1109/TPEL.2014.2347071

26. Yongseok, L., T. Hoyoung, L. Seungok, et al. "An adaptive impedance-matching network based on a novel capacitor matrix for wireless power transfer," IEEE Transactions on Power Electronics, Vol. 29, No. 8, 4403-4413, 2014.
doi:10.1109/TPEL.2013.2292596

27. Teck Chuan, B., M. Kato, T. Imura, et al. "Automated impedance matching system for robust wireless power transfer via magnetic resonance coupling," IEEE Transactions on Industrial Electronics, Vol. 60, No. 9, 3689-3698, 2013.
doi:10.1109/TIE.2012.2206337

28. Dukju, A. and H. Songcheol, "A study on magnetic field repeater in wireless power transfer," IEEE Transactions on Industrial Electronics, Vol. 60, No. 1, 360-371, 2013.

29. Khan, S. R., S. K. Pavuluri, and M. P. Y. Desmulliez, "Accurate modeling of coil inductance for near-field wireless power transfer," IEEE Transactions on Microwave Theory and Techniques, Vol. 66, No. 9, 4158-4169, 2018.
doi:10.1109/TMTT.2018.2854190

30. Ke, Q., W. Luo, G. Yan, et al. "Analytical model and optimized design of power transmitting coil for inductively coupled endoscope robot," IEEE Transactions on Biomedical Engineering, Vol. 63, No. 4, 694-706, 2016.
doi:10.1109/TBME.2015.2469137

31. Zhong, W. X. and S. Y. R. Hui, "Maximum energy efficiency tracking for wireless power transfer systems," IEEE Transactions on Power Electronics, Vol. 30, No. 7, 4025-4034, 2015.
doi:10.1109/TPEL.2014.2351496

Dr. Zhongqi Li

Dr. Wangyang Cheng

Dr. Jiliang Yi

Dr. Junjun Li