Design and Optimization of Multi-coil Wireless Charging System for Charging Area Expansion

This study proposes the multiple planar type coil structure to maintain a uniform magnetic flux density in the charging region. The proposed four loop coils of the same diameter are arranged symmetrically on the same plane, and the orthogonal current is used. Not only a rotating magnetic field is generated in the charging region, but the magnetic flux density can be kept constant within the entire charging region. The performance of the proposed coil is verified by commercial EM simulation tool.