A Switching Hybrid LCC-S Compensation Topology for Constant Current/Voltage EV Wireless Charging

Abstract

Wireless power transfer (WPT) technology has been widely applied to automobile industries, household electronics and medical devices because of its many advantages. The hybrid battery charging scheme, which combines constant voltage (CV) and constant current (CC), is considered to be quite reasonable in view of the limitations of the conventional CC/CV implementation scheme. In this study, based on the inductance and double capacitances-series (LCC-S) compensation topology, a switching hybrid topology is proposed for CC/CV electric vehicle (EV) battery charging. The topology parameters are designed according to the specified CV and zero phase angle (ZPA). In the CC charging mode, two additional capacitances are added to the topology for CC and ZPA implementation. Based on the proposed weak communication, the CC and CV charging mode can be converted via two AC switches (ACSs). The proposed hybrid system provides a simple structure, easy controllability, and stable output. A 2.5-kW experimental prototype is configured to verify the proposed hybrid charger. The maximum DC efficiencies (at 2.5-kW) of the CC and CV charging modes are 89.28% and 88.33%, respectively.