An Anti-Offset Electric Vehicle Wireless Charging System Based on Symmetrical Auxiliary Receiving Coils

The misalignment of coils in the wireless charging system of electric vehicles will lead to the dramatic fluctuation of the output voltage and the decrease of the system efficiency, thus affecting the charging quality. This paper proposes an anti-offset wireless charging system based on symmetrical auxiliary receiving coils to solve the misalignment problem. Under offset conditions, the drop in the DC voltage of the main receiving topology is compensated through the series connection of the main receiving rectifier and the auxiliary receiving rectifier. The fluctuation of the output voltage is suppressed while maintaining high efficiency, improving misalignment tolerance of the wireless charging system. The experimental results verify the effectiveness of the anti-offset proposal. The output voltage fluctuation is kept within 14.7%, and the charging efficiency is above 92%, which realizes the stabilization of the output voltage.