Inductive power transfer system with constant current and constant voltage outputs for battery charging based on double‐channel T‐circuit

Abstract To ensure the safety and effectiveness of charging a battery, constant current and constant voltage (CC‐CV) charging is widely used in inductive power transfer (IPT) systems. A double‐channel T‐circuit (DT) is proposed to obtain CC output or CV output by selecting different work modes with a simple feedback control for various power demands. With the merit of the proposed circuit, fewer components are employed compared to previous work with zero phase angle (ZPA) of inverter in the whole charging process. Besides, an IPT system using DT cascaded with LCC‐S (DTLS) is proposed to improve design freedom of the charge current and charge voltage with the constraints of the magnetic coupler (MC) parameters for CC‐CV charging. Finally, a prototype with 60 V/2 A output was built to verify the theoretical analysis. The experimental results show that the fluctuation of the charging current is less than 2% in CC mode, and that of charging voltage in CV mode is within 4% with the maximum efficiency up to 93.36% during the whole charging process.