Rail-Embedded SS-Topology Wireless Power Transfer with Reduced Leakage Magnetic Field for Automotive Power Seats

Power seats in vehicles require multiple cables, which can lead to potential short- or open-circuit issues. To address this limitation, this paper proposes a rail-embedded wireless power transfer coil. By embedding the coil within the rail structure, leakage magnetic fields are reduced by up to 90%, which helps mitigate electromagnetic interference. Additionally, various coil structures are compared and analyzed to enhance power transfer efficiency. Moreover, considering practical operating conditions where the power seat position varies, the compensation capacitance is determined based on the minimum Tx coil inductance to ensure zero-voltage-switching conditions. The theoretical analysis of power transfer efficiency is validated through simulation and experimental results. The results demonstrate that the proposed approach is well suited for power seat applications, offering a compact structure while maintaining high power transfer efficiency. In this research, a power of 70 W is successfully transferred, achieving a maximum coil-to-coil power transfer efficiency of 92% and an overall system efficiency of 80%.