Effect of hop counts on power division ratio in multi-hop power transfer via magnetic resonance

In this paper, we discuss the effect of the number of hops on the power division in wireless power transfer via magnetic resonance based on the electric circuit theory. First, a power division ratio (PDR) of single-hop power transfer to multiple receivers is addressed by using an equivalent circuit. The PDR of each receiver is shown to be inversely proportional to load resistances. Secondly, the PDR of multi-hop power transfer to multiple receivers is discussed focusing on the parity of the number of hops. Under the condition that a transmitter and intermediate couplers are arranged on an equal distance, it is needed to switch the control strategy of adjusting load resistance according to the parity of the number of hops on multi-hop power transfer to multiple receivers.