Abstract：Based on the mutual inductance between the transmitting and receiving coil as well as the resonance in circuit theory, we established an equivalent circuit model for WPT (wireless power transmission) systems using magnetic resonance coupling. According to this model, we derived how the frequency of the AC power supply affects the average power of the load and the power transmission efficiency, which is of great importance to provide an appropriate AC power supply for WPT system, but is only known perceptually now. Instead of only providing experimental demonstration in the previous literature, we theoretically analyzed the relationship between transmission distance and the average power of the load as well as the relationship between transmission distance and the power transmission efficiency. As the frequency of the AC power supply varies from 150kHz to 250kHz, theoretical derivation and simulation results demonstrate that the average power of the load maximizes when the natural resonant frequency of the transmitting and receiving coil is equal to the frequency of the AC power supply, and the power transmission efficiency is still higher than 68%. It is also demonstrated that, with the increase of transmission distance, the power transmission efficiency decreases, but the average power of the load increases first, and then decreases.
程丽敏, 崔玉龙. 磁耦合共振式无线电能传输特性研究[J]. 电工技术学报, 2013, 28(2增): 23-27.
Cheng Limin, Cui Yulong. Characteristics Research on Wireless Power Transmission Systems Using Magnetic Resonance Coupling. Transactions of China Electrotechnical Society, 2013, 28(2增): 23-27.
[1] Yuan Qiaowei, Chen Qiang, Li Long, et al. Numerical analysis on transmission efficiency of evanescent resonant coupling wireless power transfer system[J]. IEEE Transactions on Antennas and Propagation, 2010, 58(5): 1751-1758. [2] Alanson P Sample, David A Meyer, Joshua R, Smith. Analysis, experimental results, and range adaptation of magnetically coupled resonators for wireless power transfer[J]. IEEE Transactions on Industrial Elect- ronics, 2011, 58(2):544-554. [3] Seung Hwan Lee, Robert D Lorenz. A design metho- dology for multi-kW, large airgap, MHz frequency, wireless power transfer systems[C]. IEEE Energy Conversion Congress and Exposition (ECCE), 2011, Phoenix, AR. [4] Aristeidis Karalis, Joannopoulos J D, Marin Soljačić, et al. Efficient wireless non-radiative mid-range energy transfer[J]. Annals of Physics, 2008, 323: 34-48. [5] Tan L L, Huang X L, Huang H, et al. Transfer efficiency optimal control of magnetic resonance coupled system of wireless power transfer based on frequency control[J]. Sci China Tech Sci, 2011, 54: 1428-1434. [6] Seung Hwan Lee, Robert D. Lorenz. Development and validation of model for 95% efficiency, 220W wireless power transfer over a 30cm air-gap[C]. IEEE Energy Conversion Congress and Exposition (ECCE), Atlanta, USA, 2010. [7] Takehiro Imura, Yoichi Hori. Maximizing air gap and efficiency of magnetic resonant coupling for wireless power transfer using equivalent circuit and neumann formula[J]. IEEE Transactions on Industrial Electro- nics, 2011, 58(10): 4746-4752. [8] Sunkyu Kong, Myunghoi Kim, Kyoungchoul Koo, et al. Analytical expressions for maximum transferred power in wireless power transfer systems[C]. 2011 IEEE International Symposium on Electromagnetic Compatibility, 2011. [9] Erin M. Thomas, Jason D. Heebl, Carl Pfeiffer, et al. A power link study of wireless non-radiative power transfer systems using resonant shielded loops[J]. IEEE Transactions on Circuits and Systems, 2012, 59(9): 2125-2136. [10] Fu Wenzhen, Zhang Bo, Qiu Dongyuan, et al. Maximum efficiency analysis and design of self- resonance coupling coils for wireless power trans- mission system[J]. Proceedings of the CSEE, 2009, 29(18): 21-26. [11] Zhu Chunbo, Liu Kai, Yu Chunlai, et al. Simulation and experimental analysis on wireless energy transfer based on magnetic resonances[C]. IEEE Vehicle Power and Propulsion Conference (VPPC), Harbin, China, 2008. [12] André Kurs, Aristeidis Karalis, Robert Moffatt, et al. Wireless power transfer via strongly coupled mag- netic resonances[J]. Science, 2007, 317: 83-86.
2013, Vol. 28 
