Enabling IOT Wireless Distant Charging: 7.9-Mw Integrated Power Receiver at 30 cm

In this paper, we report a near-field electrodynamic wireless power transfer (EWPT) system that includes a power receiver based on a rotating magnet. This topology allows power transfer at very low frequencies (<500 Hz) to a distant and compact receiver with a high robustness.The 0.83 cm³ power receiver tested is actuated at distance by a 30-cm-diameter transmitter powered with 15 watts. Power transfers up to 7.9 mW at 30 cm from the center of the transmitter coil and 85 mW at a distance of 14 cm are experimentally demonstrated. These results are among the highest in the state of the art in terms of power density (176.8 mW/cm³/mT² at 30 cm) and distance range.