The Coil Misalignment Model of Inductively Coupled Wireless Power Transfer System: Mutual Inductance Analysis and Transfer E-ciency Optimization

A novel means of optimizing transfer e-ciency of Inductively Coupled wireless power transfer (WPT) system is presented for the flrst time. In the applications envisaged, such as electric vehicles and biomedical implants, generally the receiving coil is laterally and angularly misaligned from the transmitting coil. The numerical solution of mutual inductance between the two coils is derived and simulation result shows there is a partial optimal solution in the ranges of lateral and angular misalignments. The bigger is mutual inductance, the higher transfer e-ciency is. The novel means presented in this study allows the coil to be removable and rotatable for achieving bigger mutual inductance and optimizing transfer e-ciency. Finally the experimental results show the means is e-cient and greatly improves the transfer e-ciency. If the transfer distance is 15cm and there is no lateral misalignment, the transfer e-ciency can be improved about from 38.6% to 60.5% by turning the transmitting coil to make the tilt angle varied from 0 to …=4. This introduced technique can be widely applied to WPT system to optimize the transfer e-ciency.