Efficient, Dynamic Wireless Power Transfer

Despite widespread adoption of stationary wireless charging, dynamic wireless power transfer suffers from a sensitivity to relative movement of the device with respect to the power source. Researchers in the Fan Group have boosted efficiency to 92% by using a switch-mode amplifier and appropriate feedback with a parity-time symmetric circuit scheme. Efficiency is independent of distance (within 6 feet) and orientation, and limited to losses of the transmit and receive coils. The new lab prototype transmits 10 watts over a distance of 2-3 feet in a few milliseconds – a fraction of the time needed for a car moving at 70 miles an hour to cross a four-foot charging zone - and can be scaled up to supply the 10-100 kilowatts needed for car charging, making the PT-symmetric scheme practical for robust, efficient, 'on-the-go' wireless power transfer.

Stage of Development – Prototype
Researchers in the Fan group have built and tested a lab prototype that wirelessly transmits 10 watts over a distance of 2-3 feet in a few milliseconds. Research is ongoing.