Power Adaption Design for Multifrequency Wireless Power Transfer System

A newly developed multifrequency wireless power transfer system is designed and presented in this article. Using multiple frequency channels, the system can simultaneously deliver power to different wireless pickups with arbitrary power requirements or load characteristics. The proposed design scheme of the system topology realizes both stable power flow control and precise power adaption. The load-independent constant current output has been successfully achieved under multifrequency operation mode, which increases both system stability and fault-tolerance ability. The output characteristic can also immunize the system against undesired interferences from the reflected impedance of different receivers at other power transmission channels. Both finite element analysis and circuit simulations have verified good performance of the system under different power adaption requirements. An experimental prototype can successfully deliver a total of 18 W wireless power simultaneously to two identical resistive loads at the desired power requirement distribution of 9:1 via the same transmitter. It shows good performance in both stability and controllability.