Frequency Splitting Characteristics and Suppression Method of Three-Coil Wireless Transmission System

doi:10.11985/2018.05.005

Abstract

Abstract:

Based on the Kirchhoff law, the S-parameters, the transmission efficiency and the frequency division of the three-coil WPT system are analyzed. The phenomenon of frequency splitting is that the over-coupling between the coils causes the system to appear more than one resonant frequency. The frequency splitting occurs only in the over-coupled region. Since the internal impedance of the over-coupling region does not match the input impedance of the system, the frequency splitting phenomenon is proposed. Therefore, an impedance matching method is proposed to suppress the frequency splitting phenomenon. By adding an L-shaped impedance matching network at the transmitter and forming a conceptual impedance matching network at the receiving end, the purpose of suppressing the frequency splitting and increasing the efficiency of the system is realized. Finally, the correctness of the proposed method is compared by experiment and simulation.

Key words: Three coil WPT system, magnetic resonance coupling, frequency splitting, impedance matching

CLC Number:

TM72

Lu Qianyun,Wang Wenqing,Zhai Zhiying,Tian Zijian. Frequency Splitting Characteristics and Suppression Method of Three-Coil Wireless Transmission System[J]. Journal of Electrical Engineering, 2018, 13(5): 27-32.

Figures/Tables 9

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References 10

[1]	田子建, 杜欣欣, 樊京 , 等. 磁耦合谐振式无线输电系统不同拓扑结构的分析[J]. 电气工程学报, 2015,10(6):47-57.
	Tian Zijian, Du Xinxin, Fan Jing , et al. Analysis on different topology structures in magnetic coupling resonant WPT system[J]. Journal of Electrical Engineering, 2015,10(6):47-57.
[2]	杨庆新, 张献, 李阳 . 无线电能传输技术及其应用[M]. 北京: 机械工业出版社, 2014.
[3]	Andre Kurs, Aristeidis Karalis, Robert Moffatt . Wireless power transfer via strongly coupled magnetic resonances[J]. Science, 2007,317(6):83-86.
[4]	黄学良, 谭林林, 陈忠 , 等. 无线电能传输技术研究与应用综述[J]. 电工技术学报, 2013,28(10):1-11.
	Huang Xueliang, Tan Linlin, Chen Zhong , et al. Review and research progress on WPT technology[J]. Transactions of China Electrotechnical Society, 2013,28(10):1-11.
[5]	张献, 杨庆新, 陈海燕 , 等. 磁耦合谐振式传能系统的频率分裂特性研究[J]. 电机工程学报, 2012,32(9):167-171.
	Zhang Xian, Yang Qingxin, Chen Haiyan , et al. Research on characteristics of frequency splitting in electromagnetic coupling resonant power transmission systems[J]. Proceedings of the CSEE, 2012,32(9):167-171.
[6]	Lyu Yuelong, Meng Fanyi . A method of using nonidentical resonant coils for frequency splitting elimination in wireless power transfer[J]. IEEE Transactions on Power Electronics, 2015,30(11):6097-6107.
[7]	Huang X L, Tan L L, Wang W. Resonant frequency splitting analysis and optimation of wireless power transfer system[C]. PIERS Proceedings, Moscow, 2012,49(1):684-688.
[8]	Huang Runhong, Zhang Bo . Frequency splitting phenomena of magnetic resonant coupling wireless power transfer[J]. IEEE Transactions on Magnetic, 2014,50(11):1-4.
[9]	Zhang Yiming, Zhao Zhengming, Chen Kainan. Frequency splitting analysis of magnetically-coupled resonant wireless power transfer[C]. IEEE Energy Conversion Congress and Exposition, 2013: 2227-2232.
[10]	Huang Yong, Shinohara Naoki, Mitani Tomohiko . Impedance matching in wireless power transfer[J]. IEEE Transactions on Microwave Theory and Techniques, 2017,65(2):582-590.

参数	数值	参数	数值
L₁/μH	1.0	R_p2、R_p3/Ω	0.5
L₂、L₃/μH	20	R_S、R_L/Ω	50
C₁/pF	253	k₁₂	0.1
C₂、C₃/pF	12.67	f₀/MHz	10
R_p1/Ω	0.1

d/cm	10	15	20	25	30	35
效率1	0.21	0.30	0.43	0.59	0.55	0.41
效率2	0.51	0.54	0.60	0.59	0.56	0.50