超颖材料特性对无线电力传输系统的影响

为了提高无线电力传输系统的传输效率和增大传输距离,在无线电力传输系统中采用了超颖材料.从负折射率和倏逝波出发,通过公式推导和仿真分析,探讨了超颖材料对倏逝波的增强效应.结果表明:当磁导率为负值时,超颖材料对倏逝波磁场的增强效应可使耦合系数成倍增大;而负的介电常数所引起的电场增强效应对耦合系数的影响较小;在现有无线电波段工作频率和厘米量级的传输距离条件下,负折射效应无法提高耦合系数,即无法提高传输效率,而需要制作工艺相对简单、磁导率为负的单负材料,以达到提高无线电力传输效率的目标.

Influences of Characteristics of Metamaterials on Wireless Power Transmission

In order to improve the efficiency and increase the distance of the wireless power transmission system, metamaterials were applied. The formula derivation and simulation analysis verified the ability of metamaterials to improve the transmission efficiency respectively from the point of view of negative refraction and the evanescent wave. It is concluded that negative permeability can enhance the magnetic field and exponentially increase the coupling coefficient, while negative permittivity can only make little contribution to the coupling coefficient; and that the focusing effect caused by negative refraction cannot improve transmission efficiency under the radio band within a couple of centimeters. The matematerials with single negative permeability is good enough to improve the efficiency.