volume | PIER Journals

Abstract

In the dynamic wireless charging system of electric vehicles, the misalignment between transmitting and receiving coils will cause drastic changes in the coupling coefficient, which will lead to system instability. A dynamic and static wireless power transfer system superimposed dislocation coil (SDC) structure is proposed in this paper. This structure ensures a constant coupling coefficient between the transmitting and receiving coils of the dynamic and static wireless power transfer system for electric vehicles. Firstly, the variation law of the coupling coefficient of the SDC structure is analyzed. Secondly, a quasi-constant coupling coefficient optimization method is proposed based on the SDC structure to obtain the coil parameters that meet the requirements. Finally, according to the optimization results, an experimental platform for wireless power transfer based on the SDC structure is built. The experimental results show that the maximum fluctuation rate of the inter-coil coupling coefficient is only 3.12% when the misalignment between the transmitting coil and the receiving coil is within half of the outer length of the transmitting coil. Thus, the correctness and effectiveness of the proposed structure and method are verified.

1. Wei, G. and J. Feng, "An efficient power and data synchronous transfer method for wireless power transfer system using double-D coupling coil," IEEE Transactions on Industrial Electronics, Vol. 68, No. 11, 10643-10653, Nov. 2021.
doi:10.1109/TIE.2020.3038081

2. Mohammed, S. A. Q. and J. W. Jung, "A comprehensive state-of-the-art review of wired/wireless charging technologies for battery electric vehicles: Classification/common topologies/future research issues," IEEE Access, Vol. 9, 19572-19585, Jan. 2021.
doi:10.1109/ACCESS.2021.3055027

3. ElGhanam, E. and H. Sharf, "On the coordination of charging demand of electric vehicles in a network of dynamic wireless charging systems," IEEE Access, Vol. 10, 62879-62892, Jun. 2022.
doi:10.1109/ACCESS.2022.3182700

4. Farajizadeh, F. and D. M. Vilathgamuwa, "Expandable N-legged converter to drive closely spaced multitransmitter wireless power transfer systems for dynamic charging," IEEE Transactions on Power Electronics, Vol. 35, No. 14, 3794-3806, Apr. 2020.
doi:10.1109/TPEL.2019.2939848

5. Mahesh, A. and B. Chokkalingam, "Inductive wireless power transfer charging for electric vehicles - A review," IEEE Access, Vol. 9, 137667-137713, Sep. 2021.
doi:10.1109/ACCESS.2021.3116678

6. Choi, S. and S. Jeong, "Ultraslim S-type power supply rails for roadway-powered electric vehicles," IEEE Transactions on Power Electronics, Vol. 30, No. 11, 6456-6468, Nov. 2015.
doi:10.1109/TPEL.2015.2444894

7. Ahmad, A., M. Alam, and R. Chabaan, "A comprehensive review of wireless charging technologies for electric vehicles," IEEE Transactions on Transportation Electrification, Vol. 4, No. 1, 38-63, Mar. 2017.
doi:10.1109/TTE.2017.2771619

8. Jeong, S. and Y. J. Jang, "Charging automation for electric vehicles: Is a smaller battery good for the wireless charging electric vehicles?," IEEE Transactions on Automation Science and Engineering, Vol. 16, No. 1, 486-497, Jan. 2019.
doi:10.1109/TASE.2018.2827954

9. Zhang, X. and Z. Yuan, "Coil design and efficiency analysis for dynamic wireless charging system for electric vehicles," IEEE Transactions on Magnetics, Vol. 52, No. 7, 1-4, Jul. 2016.

10. Li, Z. and J. Yi, "Modeling and design of a transmission coil and four cascaded receiving coils wireless charging structure with lateral misalignments," IEEE Access, Vol. 8, 75976-75985, Apr. 2020.
doi:10.1109/ACCESS.2020.2988888

11. Budhia, M., G. Covic, J. T. Boys, and C.-Y. Huang, "Development and evaluation of single sided flux couplers for contactless electric vehicle charging," 2011 IEEE Energy Conversion Congress and Exposition, 614-621, Oct. 2011.

12. Budhia, M. and J. T. Boys, "Development of a single-sided flux magnetic coupler for electric vehicle IPT charging systems," IEEE Transactions on Industrial Electronics, Vol. 60, No. 1, 318-328, Jan. 2013.
doi:10.1109/TIE.2011.2179274

13. Zaheer, A. and G. A. Covic, "A bipolar pad in a 10-kHz 300-W distributed IPT system for AGV applications," IEEE Transactions on Industrial Electronics, Vol. 61, No. 7, 3288-3301, Jul. 2013.
doi:10.1109/TIE.2013.2281167

14. Kim, S. and G. A. Covic, "Tripolar pad for inductive power transfer systems for EV charging," IEEE Transactions on Power Electronics, Vol. 32, No. 7, 5045-5057, Jul. 2017.
doi:10.1109/TPEL.2016.2606893

15. Li, Y. and J. Zhao, "A novel coil with high misalignment tolerance for wireless power transfer," IEEE Transactions on Magnetics, Vol. 55, No. 6, 1-4, Jun. 2019.

16. Wang, Z. and C. Hu, "Design of magnetic coupler for inductive power transfer system based on output power and efficiency," Transactions of China Electrotechnical Society, Vol. 30, No. 19, 26-31, 2015.

17. Li, Z. and J. Li, "Design and optimization of asymmetric and reverse series coil structure for obtaining quasi-constant mutual inductance in dynamic wireless charging system for electric vehicles," IEEE Transactions on Vehicular Technology, Vol. 71, No. 3, 2560-2572, 2021.
doi:10.1109/TVT.2021.3138072

18. Li, Z. and S. Li, "Mutual inductance calculation and optimization of multi-receiver positive and negative series coil structure in dynamic wireless power transfer systems," Transactions of China Electrotechnical Society, Vol. 36, No. 24, 5153-5164, 2021.

19. Otomo, Y. and H. Igarashi, "A 3-D topology optimization of magnetic cores for wireless power transfer device," IEEE Transactions on Magnetics, Vol. 55, No. 6, 1-5, Jun. 2019.
doi:10.1109/TMAG.2019.2900744

Dr. Zhongqi Li

Dr. Xinbo Xiong

Dr. Liquan Ren

Dr. Pengsheng Kong

Dr. Yang Zhang

Dr. Junjun Li