Reconfigurable Compensation Topology for Efficient Wireless Energy Conversion in Electric Vehicle CCCV Charging with Zero Voltage Switching

This paper proposes a reconfigurable compensation topology using only passive inductors and capacitors to achieve efficient constant current and constant voltage charging for electric vehicles through wireless power transfer. The core contribution employs two AC switches to reconfigure the transmitter matching network, enabling smooth mode transitions between constant current and constant voltage without complex control or frequency variation. The method uses first harmonic approximation and Kirchhoff's laws to derive resonant conditions that ensure load-independent output current and voltage, zero phase angle for unity power factor, and zero voltage switching across the full load range. Compared with conventional approaches - such as secondary-side DC-DC converters that introduce extra losses, variable-frequency techniques prone to bifurcation, or series-series and double-sided LCC topologies that require complex couplers or fail zero phase angle in constant voltage mode - this passive solution offers simpler implementation, reduced cost, and improved reliability. Simulations at 85 kHz with DD coils confirm stable constant current output of 15.7 A, constant voltage output of 420 V, reliable zero voltage switching, and robust response under load steps from 6 kW to 3.2 kW. The topology positions electric vehicles as mobile energy storage units supporting vehicle-to-grid interactions, with potential to enable bidirectional energy exchange, enhance grid stability, facilitate renewable integration, and promote electric vehicle adoption through cost-effective, resilient energy conversion solutions.