Study on Interoperability and Misalignment Tolerance of Electric Vehicle Wireless Charging System Based on a Novel Asymmetrical Bipolar Coil

Electric vehicles (EVs) wireless charging systems have several different coil types, and each coil type may not be compatible with the others, leading to interoperability issues. Additionally, misalignment may occur between the transmitter and receiver during parking. The interoperability and misalignment tolerance problems of wireless charging for EVs need to be addressed. To solve these problems, a novel asymmetric bipolar coil structure with interoperability and misalignment tolerance is proposed. In this paper, four alternative structures with interoperability and misalignment tolerance characteristics are firstly proposed based on existing coupling structures, and an optimal coupling structure is finally selected through finite element analysis (FEA) of these four structures. An experimental prototype was also fabricated to validate this proposal. The effectiveness of the proposed asymmetric bipolar coil is verified through calculations, simulations, and experiments. The final overall transmission efficiencies obtained are all higher than 85%, regardless of the unipolar, bipolar, and quadrupolar coil structures were the transmitting coils.