基于Halbach效应的磁屏蔽无线输电耦合机构研究

Study on Wireless Power Transmission Coupling Mechanism with Magnetic Shielding Based on Halbach Effect

针对主动磁屏蔽需要设置额外激励源、被动磁屏蔽所采用的磁屏蔽材料价格昂贵等问题,在传统DD线圈结构基础之上,提出了一种基于Halbach效应的磁屏蔽无线输电耦合机构。首先,提出了具有磁屏蔽效应的无线输电耦合机构拓扑,基于耦合机构等效磁路模型,从理论上分析了其产生磁屏蔽效应的原理;其次,采用微元法推导了耦合机构在空间中任意平面的磁场强度表达式;最后,搭建实验平台,验证了耦合机构的无线输电性能及磁屏蔽效果。结果表明,Halbach效应线圈在保证输电效率与DD线圈基本一致的同时,能有效削弱耦合机构外的磁场强度,提高磁屏蔽效果。

Aimed at problems such as the setup of an additional excitation source required by active magnetic shielding and the expensive magnetic shielding materials used in passive magnetic shielding,a wireless power transmission(WPT)coupling mechanism with magnetic shielding based on Halbach effect is proposed on the basis of the traditional DD coil structure.First,the topology of WPT coupling mechanism with magnetic shielding effect is proposed,and the principle for the magnetic shielding effect is analyzed theoretically based on the corresponding equivalent magnetic circuit model.Second,the expression for the magnetic field intensity of the coupling mechanism on any plane in the space is derived using the micro-element method.Finally,an experimental platform was built to verify the WPT performance and magnetic shielding effect of the proposed coupling mechanism.Results show that the Halbach effect coil can effectively weaken the magnetic field intensity outside the coupling mechanism and improve the magnetic shielding effect while ensuring that the power transmission efficiency is basically the same as that of the DD coil.