Inductive coupling solutions dominate the wireless power transfer (WPT) market, offering efficient transfer of power at close range, primarily for charging consumer goods. However, many challenges persist to further spread WPT solutions to new markets (e.g. charging of electric vehicles, of internet of things systems, of medical devices…).

How to transfer power safely and efficiently to multiple receivers that are compact enough for electronic integration over extended distances in cluttered environments?

A first level of comparison of WPT technologies can be made on figures of merit such as the power level, the transmission range, the receiver and transmitter size, and the overall efficiency. However, some practical constraints arising in actual applications are often overlooked and might limit the technology industrial transfer.

For example, is the considered WPT technology able to transfer power:

• - to multiple receivers,
• ​- independently of the receiver orientation,
• - safely around humans,
• - safely in presence of metallic objects,
• - through conductive media such as metal or seawater?