The application of the metamaterial (MM) in wireless power transfer (WPT) system has received a great deal of attention in improving the transfer efficiency and reducing the leakage of electromagnetic field (EMF) in recent years. However, most of the analytical methods for MM-inspired WPT system are based on microwave technologies, such as negative refraction effect, magnetic dipole coupling model and magneto-inductive wave theory. In this study, the equivalent circuit model of the MM in the WPT system is analysed in detail. Two different types of MMs, Mu-Negative-Magnetic (MNM) and Mu-Near-Zero (MNZ), are constructed to verify this method. In particular, a tuning strategy by changing the distances between the drive (load) loop and internal coils is established to improve the power transfer efficiency for the WPT system with the MNM-MM. In addition, the MNZ-MM is described to cancel EMF leakage in the WPT systems by this method. Moreover, a series of practical experiments are carried out to prove the numerical analysis, which are well consistent with the theoretical solution employed by the Advanced Design System software. Finally, the combination of two types of MMs applied in the WPT system is also discussed.

中文翻译：

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无线电力传输系统中Mu负磁和Mu-Near-Zero超材料的等效电路方法

近年来，超材料（MM）在无线电力传输（WPT）系统中的应用在提高传输效率和减少电磁场（EMF）泄漏方面引起了广泛关注。但是，基于MM的WPT系统的大多数分析方法都是基于微波技术，例如负折射效应，磁偶极耦合模型和磁感应波理论。在这项研究中，详细分析了WPT系统中MM的等效电路模型。构造了两种不同类型的MM，即Mu-Negative-Magnetic（MNM）和Mu-Near-Zero（MNZ），以验证该方法。特别是，建立了一种通过更改驱动器（负载）环路和内部线圈之间的距离的调整策略，以提高带有MNM-MM的WPT系统的功率传输效率。另外，描述了MNZ-MM通过这种方法消除WPT系统中的EMF泄漏。此外，进行了一系列实际实验以证明数值分析，这与Advanced Design System软件采用的理论解决方案非常吻合。最后，还讨论了在WPT系统中应用的两种类型的MM的组合。