A Novel Type of Transmitter With A-R Coil for Large-Scale Spatial Wireless Power Transfer

Due to the rapid attenuation nature of electromagnetic fields in wireless power transfer (WPT) system within a large-scale spatial, it is difficult to realize spatial scale spanning to meet the current urgent demand for power supply of multiloads electronic devices in unmanned indoor scenarios such as Internet of Things and automatic warehouse. In order to solve this problem, a novel transmitting structure with active relay coil is proposed in this article for realizing power transfer at any location and number of loads within large-scale 3-D space. First, the transmitter can be ensured that the winding directions of adjacent planar coils on the ceiling and floor of the space are different to increasing the magnetic field density; at the same time, the longitudinal direction of the magnetic field on the same side in the spatial region can be guaranteed to be the same to extend the magnetic flux paths and the spatial transfer scale. Through experimental studies, 12 loaded light bulbs scattered in different positions within the space of <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$1.8\times 1.4\times 2.0$ </tex-math></inline-formula> m were all lit with the total efficiency of 80%, not limited to that number of loads. Under the single load, the minimum transfer efficiency is 8.2% and the maximum is 50%.