节点文献
无线电力传输中磁性超材料的设计与应用研究
Design and Application of Magnetic Metamaterials in Wireless Power Transfer
【作者】 华立群；
【导师】 肖高标；
【作者基本信息】 上海交通大学 ， 电子与通信工程（专业学位）， 2017， 硕士
【摘要】 人工电磁超材料,作为近些年的研究热点,已经在各频段被用来构造具有特殊电磁特性的新器件,并被应用于各领域之中。在众多超材料结构中,开口环谐振器和螺旋谐振器是使用最为广泛的超材料单元结构,尤其是在遥测和无线电力传输系统中,基于这两种结构的超材料应用于无线电力传输系统时,能使系统的性能得到明显提升,且具备了简单的加工工艺和较低的制造成本等优势,有着很大的发展和实用前景。本文通过数值仿真的方式设计了在29.8 MHz下具有低损耗和-1磁导率特性的磁性超材料,搭建了相距40厘米的无线电力传输系统仿真平台,通过该磁性超材料汇聚线圈之间的磁场,从而对无线电力传输系统进行了效率优化,并在该基础上讨论了进一步提升效率的方案;对磁性超材料介质板进行了改进设计,用具有近零磁导率的SR单元调换其中央位置的谐振单元,并结合铁氧体介质板,探究和对比了该两种方式对无线电力传输系统性能的提升效果。本文还对无线电力传输系统和所涉及的超材料单元建立了等效分析模型,基于S参数提取法研究了双面方形螺旋谐振器单元的几何参数对其自身谐振频率和磁导率的影响,并总结了调节该结构谐振频率和磁导率的方法。
【Abstract】 Artificially constructed materials,as a research hotspot in recent years,have been applied in various fields and the construction of new devices in almost all frequency ranges.The split-ring resonators(SRRs)and spiral resonators(SRs)are the most widely used metamaterial cells,especially in telemetry and antenna systems.The performance of the wireless power transfer system can be greatly improved by a magnetic metamaterial slab composed of respective SRRs and SRs,which has the advantage of simple fabrication process at a low cost.In this paper,a magnetic metamaterial slab is designed with low loss and-1 permeability at 29.8 MHz by means of numerical simulation,and a 40-centimeterdistance wireless power transmission system is built in HFSS.The power transfer effiency of the system can be optimized by using this magnetic metamaterial slab.After the improvement of the efficiency caused by the slab,another method of improving the efficiency is further discussed where the SR unit cells in the center of slab are replaced with the cells with near zero permeability.The effects of the modified magnetic metamaterial slab and metamaterial slab combined with ferrite slabs are explored.The equivalent analytical models are also established for WPT system and metamaterials.Based on the S-parameter retrieval method,the influence of geometrical parameters on the resonant frequency and permeability of double-sided square spiral resonator is studied and a method for adjusting the resonant frequency and the permeability of the SR structure is concluded.