Optimal Design of Wireless Power Transfer System Based on Spherical Motion Device

The multi-degree-of-freedom spherical motion device usually requires a built-in data acquisition and processing module and a wireless charging part in its bionic design, while the traditional disc-shaped receiving coil increases with the deflection angle, the system coupling coefficient and mutual inductance will decrease causing the increased power transmission fluctuation and greatly decreased transmission power. In this paper, a tile-shaped receiving coil is designed to ensure the power output when the rotation offset occurs. Then, the formula of radio energy transmission characteristics is derived and verified by finite element simulation. It is proved that the coupling coefficient peak value of the new structure is increased by 12.68% and the variation fluctuation is reduced by 2.26%. The output of the new system at each deflection angle has been improved overall. Finally, an experimental platform is built to verify the accuracy of the simulation analysis and the effectiveness of power transmission.