Duty Cycle Control of Dual-side LCC Compensated Bidirectional Wireless Charging Systems

In wireless power transfer, coordinated control of both sides generally relies on the synchronization of isolated gate signals, which remains an essential challenge due to inherent frequency deviation of the gate signals between the primary and secondary sides. This paper proposes a novel duty cycle control scheme for the dual-side LCC topology without the need of any extra circuits, which can effectively solve the synchronization problem in electric vehicles charging and realize bidirectional power transfer at a low cost. Detailed mathematical analyses of power transfer and output characteristics are provided. In addition, operating stages with typical waveforms under the proposed control scheme are illustrated. Finally, simulation and experimental results of power transfer characteristics and different charging modes are provided to demonstrate the effectiveness of the proposed scheme.