Abstract：The temporal and spatial characteristics of magnetic fields in the magnetic resonant wireless power transfer (MR-WPT) system are researched in this paper based on the basic structure and the power transfer states of the system. The magnetic fields are obtained by applying Biot-Savart law on a single turn coil. Then the polarization formula of the magnetic field intensity vectors is derived and three polarization states along with their corresponding conditions are analyzed. We found that the linear polarization is an intrinsic characteristic of the MR-WPT system, and the magnetic field polarization possesses the distribution characteristic. The ratio of magnetic field components, the phase difference of the magnetic field components, and the axial ratio are used as the polarization parameters, and the distribution of the axial ratio of a solenoid-coil system is calculated on the meridian plane. A closed dish-like surface on which the linear polarization distributes is found. Additionally, the polarization of the magnetic field in the spiral-coil system is also analyzed. The theoretical analysis and results are verified via both simulations and experiments.
汪泉弟, 康健炜, 王赢聪, 李万路, 张婵. 磁谐振无线电能传输系统空间磁场的时空特性[J]. 电工技术学报, 2018, 33(19): 4486-4495.
Wang Quandi, Kang Jianwei, Wang Yingcong, Li Wanlu, Zhang Chan. Temporal and Spatial Characteristics of Magnetic Fields in Magnetic Resonant Wireless Power Transfer System. Transactions of China Electrotechnical Society, 2018, 33(19): 4486-4495.
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2018, Vol. 33 
