Two/Three-Coil Hybrid Topology for WPT Systems Charging Electric Bicycles

Wireless power transfer (WPT) for charging electric bicycles (EBs) can save people from the tiresome plugging action and avoid electric shot hazards, especially in adverse weather. This paper proposed a two/three-coil hybrid topology to achieve constant current (CC) and constant voltage (CV) for charging EBs, simplifying the control schemes. The system realizes CC output with two-coil topology, and operates in CV mode with three-coil topology by turning on a switch. To demonstrate the validity of the proposed methods, an experimental setup was built. The performance of the two/three-coil hybrid system indicates that the method can charge EBs with the maximum efficiency at 91.23%. Moreover, the fluctuations of charging current and voltage are less than 0.64% and 2.12% in the whole charging profile.