A constant-current WPT system with S/S compensated topology and full-wave rectification

In wireless charging applications, the constant current (CC) charging process is a critical stage that garners significant attention. This paper presents a novel S/SP compensation topology that achieves load-independent CC output, as well as offering significant design flexibility. To minimize rectification losses across the rectifier diodes during CC output, a full-wave rectifier structure is selected for the wireless power receiver. Building upon these considerations, this paper innovatively proposes an inductor reuse scheme between the S/SP compensation topology and the full-wave rectification structure. The proposed reuse design approach enables zero phase angle (ZPA) operation and configures the wireless power transfer (WPT) system as a cascaded arrangement of an S/S compensation topology and a full-wave rectifier. The efficacy of the proposed design is validated using a 6-A CC output prototype, and experimental results demonstrate a maximum ±1.3% output current fluctuation. The prototype achieves inverter soft-switching operation and a 94.2% peak efficiency across a four-fold load variation range.