偏谐振工作状态下的无线电能传输系统

In the working process of series-series wireless power transfer (WPT) system, in order to avoid the occurrence of detuning, complex frequency control is needed. When the coupled mutual inductance M=0, the transmitter resonates and large power will be consumed on the parasitic resistor of primary coils, which will lead to the security risks. Regarding the issues above, a working mode that the operating frequency of the WPT system is larger than the resonant frequency of transmitter and receiver, was proposed. In this mode, the capacitance reflected from the secondary circuit could be used to counteract the inductance of the primary circuit. There is no need for the frequency tracking and the system having low output power when M=0. In order to verify the validity and universality of the working mode, two WPT prototypes were designed respectively based on the class E amplifier and half-bridge inverter. The experimental results show that in the proposed mode, the output power of both WPT prototypes is less than 2 W when M=0. Meantime, with the increase of M, both the output power and efficiency rise and the prototype reaches the transfer efficiency of 86.3% at 19.1 W output power.