Mid-range wireless power transfer to multiple small receivers using metasurface

In this paper, we analyze the characteristics of a printable mid-range one transmitter coil to four small receiver coils wireless power transfer (WPT) system. The size of the transmitter coil is 40.4cm ×40.4cm × 2mm. The four receiver coils is identical and each one has the size of the 13.6cm × 13. 6cm × 1mm. The spacing distance is 80cm between the transmit coil to the surface of the four receiver coils. Note that it must be a low efficiency magnetic resonate system due to the bigger spacing distance compared to the size of both the transmitter and receivers. Therefore, a metasurface is proposed and integrated with the WPT system to enhance the transfer efficiency. The simulation results show that the total efficiency can be as high as 92% when all parts of the system are put on the optimized position.