A research group led by Assistant Professor Takuya Sasaya of the University of Tokyo has developed a technology to transform a room into a wireless power transmission system.Small charging cabinets, wireless charging rooms, and cableless factories that scale up to power equipment without cables could also be realized.
Wireless power transfer technology is already available for charging small electrical devices (smartphones, electric toothbrushes, etc.).However, the current system requires the device to remain stationary and within a few centimeters of the charging mat or charging dock.
The system developed this time uses the multi-directional distributed current of the conductive surface incorporated in the wall. Called "multi-mode semi-static cavity resonance", it is a small coil type that generates a three-dimensional magnetic field pattern in the entire room (width 3m x depth 3m x height 2m) and is attached to electric devices such as smartphones, light bulbs, and electric fans. Can be efficiently coupled with the receiver.To maximize efficiency, the coiled receiver needs to be adjusted to the proper angle with respect to the magnetic field, but power transfer efficiencies in excess of 37.1% can be achieved anywhere in the room, even while the device is in operation.
This method offers greater flexibility than traditional methods (such as coil-based transmitters).It also meets the guidelines developed by the Federal Communications Commission (FCC) and the Institute of Electrical and Electronics Engineers (IEEE) for safety (especially how much power can be absorbed by living tissue during operation).The safe demonstration of room-scale wireless power transfer will allow the technology to be widely applied to power electronic devices, whether used in industrial or personal living spaces.
Paper information:[Nature Electronics] Room-scale magnetoquasistatic wireless power transfer using a cavity-based multimode resonator
