A Battery Wireless Charger With Full Load Range Soft-Switching Operation and Zero-Switching-Loss Inverter

To enhance the efficiency and soft-switching stability of the battery wireless charger within the full load range, a soft-switching battery wireless charger (SS-BWC) is presented. The presented SS-BWC can achieve smooth switching from constant current mode to constant voltage mode under the condition of uncomplicated control. The high-frequency inverter (HFI) can operate with zero switching loss in the whole charging process by adopting a novel auxiliary resonant network, which can effectively reduce the switching loss in the HFI and refrain from soft-switching loss due to the compensation element parameter perturbation. Besides, the HFI adopts a new modulation method, and only one power switch tube is in the high-frequency switching state in a switching cycle, which is also conducive to enhancing efficiency. The operating principle of the presented SS-BWC is elaborated in detail, and the realization conditions for soft-switching are also designed. Finally, an experimental device is built to verify the feasibility and superiority of the proposal.