Abstract—In multiple receivers of resonant wireless power
transfer, selective power flow among the loads is an important
issue. This paper proposes a new method to control power division. The two-coil structure with different resonant frequencies
of the sending and receiving loops is modeled and analyzed. The
efficiency is proved to peak at the resonant frequency of the receiving loop, regardless of the resonant frequency of the sending loop.
Using this feature, selective power transfer can be achieved by setting the receiving loops at different resonant frequencies. The efficiency of a particular load is greatly influenced by the driving frequency. The multiple-load system with different resonant frequencies is modeled and the efficiency expression of each load is deduced.
The mutual inductances of the receiving coils have a small impact
on the efficiency distribution. The closer the resonant frequencies
of the receiving loops, the less isolated the related loads. The calculations and the experiments confirm the analysis.