Research On The Distance Characteristics Of Wireless Power Transfer System Based On Magnetic Resonance Coupling

Magnetic resonance coupling wireless power transfer is a new technology emerging in recent years, unlike the laser energy transfer which achieve power based on far-field. It also is a breakthrough in inductively coupled power transfer technology, the theoretical basis is coupled mode theory, which is based on near-field magnetic resonance coupling to achieve power. Efficiency and distance are the hotspot researches in magnetic resonance coupling wireless power transfer.This paper focuses on the transmission distance of magnetic resonance coupling wireless power, and it examines this question through theory and experiment. At first, the background introduces the theoretical basis of magnetic resonance coupling wireless power transfer technology, that is coupled-mode theory. On this basis, this paper establish coupling circuit model, and quantitatively analyze transmission distance. And then, overall design of magnetic resonance coupling wireless power transfer experiment are defined. and designed a half-bridge inverter as an experimental high-frequency power excitation source, completed system design of electromagnetic launch and electromagnetic receiver system, thereby it can complete a magnetically coupled resonant wireless power transfer system. Finally, the transfer distance characteristics of magnetically coupled resonant wireless power transmission system were investigated by use of the experimental methods. It is shown that: the coil radii determines the transfer distance when the wire radii and materials are fixed. The thick coil wire apparently received better results when the resonance coil radii and materials are fixed. The higher the conductivity of the coil materials, the longer the transfer distance when the coil radii and wire radii are fixed. Meanwhile, the resonance frequency also determines the transfer distance. Thus provides an useful reference for improving the wireless power transfer range and system optimization designing. Moreover, the indefinite magnetic media has a significant partial focusing effect on the power. This paper designs a kind of indefinite magnetic media with planar circular spirals. It is shown that it also can highly improve the distance.