A Wireless Power Transfer Charger with Hybrid Compensation Topology for Constant Current/Voltage Onboard Charging

Abstract

Compared with plugged-in chargers, wireless power transfer (WPT) systems for battery chargers have numerous advantages, e.g., safety, efficiency, and convenience. To satisfy the important wireless charging requirements of efficiency and safety of the battery, this paper proposes a constant current/voltage (CC/CV) charging compensation topology with near-communication based on receiving-side hybrid topology switching, which is unaffected by the dynamic loads. The proposed hybrid topology is systematically analyzed by using the M-mode, and the system parameters are designed to satisfy the constraints of zero phase angle (ZPA) and the specified CC output. In the CV mode, one shunt capacitor is employed to the compensation topology for the CV output and ZPA realization. Both the CC and CV modes are operated under the conditions of zero voltage switching (ZVS) for reducing the loss of the WPT systems. The proposed hybrid compensation topology is controlled by the receiving side and does not require real-time communication to avoid sophisticated control logic. Finally, a 1.1-kW experimental prototype charger based on DS-LCC and LCC-S topologies was established to verify the charging performance of the proposed WPT systems. The maximum efficiency of the proposed WPT charger was found to be approximately 91%. The experimental results were consistent with those of the theoretical analysis.

Keywords

• wireless power transfer
• hybrid compensation topology
• constant current/voltage charging
• zero phase angle
• battery charging