Compact Non-uniform Planar Metasurface for Efficiency Enhancement of Wireless Power Transfer

Negative permeability (MNG) non-uniform metasurface with a compact size of 80×80 mm
²
is proposed for power transfer efficiency (PTE) enhancement of planar magnetically coupled resonance wireless power transfer (PMCRWPT) system. The PMCR-WPT system with the non-uniform metasurface is investigated by simulation and measurement. The simulated and measured results of PMCR-WPT system with the non-uniform metasurface achieved the maximum PTE of 59.4% and 54.7%, respectively. In addition, the highest PTE improvement obtained 42.2% in simulation and 35.5% in measurement compared with free space case. Moreover, the PTE of PMCR-WPT system with the proposed non-uniform metasurface case was approximately 2.3% greater than the uniform metasurface case over effective distances. The results indicated that the non-uniform metasurface can be applied for future wireless power transfer system.