Selective wireless power transfer for multiple receivers by using magnetic resonance coupling

Wireless power transfer (WPT) is expected to spread around the world. WPT has two types, one is magnetic induction and another is magnetic resonant coupling (MRC). In magnetic induction, the amount of received power is determined by the transfer distance and the amount of magnetic flux through receiving coil. Therefore in transferring power to multiple receivers at each fixed transfer distance, power is transferred to all of the receiving coils through which magnetic flux passes. It is the problem that power may be distributed to the other receivers. This paper proposes transferring power to only one of various receivers by using MRC, selective WPT. In MRC, since a receiver is coupled to a transmitter by the resonant frequency, one receiver is distinguished from the others by the frequency. Experimental results represented the success of selective WPT. This proposal is useful for transferring power to one appropriate receiver independently of other receivers.