New power transfer technology provides unprecedented freedom for wireless charging

Science Daily  February 1, 2022 Using electromagnetics researchers in Finland have developed a free-positioning wireless power transfer technology that can direct power to individual devices without needing plugs, tracking devices , or complex computing. Devices can be charged while they are moving. Multiple transmitters (Txs) are placed in a pad-like area, and the transmitter coils are optimally excited to enable robust and efficient power transfer to movable receivers within the charging area. The configuration enables almost continuous magnetic flux path from a set of Tx coil(s) to another set of Tx coil(s) through the receiver coil ferrite core ensuring efficient […]

A system for robust and efficient wireless power transfer

Phys.org  May 18, 2020 Wireless power transfer set-ups typically suffer from an inherent sensitivity to the relative movement of the device with respect to the power source. Previous implementations to deliver robust wireless power transfer even while a device is moving rapidly have relied on an inefficient gain element based on an operation-amplifier circuit, which has inherent loss, and hence have exhibited poor total system efficiency. Researchers at Stanford University have shown that robust and efficient wireless power transfer can be achieved by using a power-efficient switch-mode amplifier with current-sensing feedback in a parity–time symmetric circuit. The parity–time symmetry guarantees […]