Low Frequency Magnetic Metasurface for Wireless Power Transfer Applications: Reducing Losses Effect and Optimizing Loading Condition

In this paper, we analyze the operative limits and the conditions characterizing low frequency magnetic metasurfaces used in practical Wireless Power Transfer applications. In the literature, the analytical modeling of similar structures, allowing a control over their frequency response, has been already demonstrated. By starting from this point, practical aspects and differences between a purely theorical approach and real scenario constraints are highlighted and discussed. In particular, accurate and representative numerical simulations are conceived, by firstly analyzing and quantifying the effect on the metasurface performance of the resistive losses characterizing its constitutive conductive material. Then, the metasurface performance deviations produced by the interactions with additional radiofrequency coils, as in Wireless Power Transfer arrangements, are considered. In the latter case, the loading condition at the receiving coil was specifically studied. For both the considered scenarios, detailed conditions and possible solutions to alleviate these detrimental effects, which deviate the metasurface response from the desired behavior, are derived. This work can be useful to guide the design process of low frequency magnetic metasurfaces in a practical environment, achieving the best performance possible for Wireless Power Transfer applications.