Analysis of Symmetric Two and Four-coil Magnetic Resonant Coupling Wireless Power Transfer

& nbsp;This study examined the efficiency of power transfer for two-coil and four-coil spiral magnetic res-onant coupling wireless power transfer (WPT) using distance to coil diameter (D/dm) ratio and reflection coef-ficient, S21 value. Adding resonators reduced the total resistance in the two-coil WPT system while increas-ing the S21 values of the whole system. A same-size spiral coil was proposed for the system and simulated using computer simulation technology (CST). A proto-type with similar specifications for a four-coil design was implemented for verification. The proposed method yielded an optimal efficiency of 76.3% in the four-coil system, while the two-coil WPT yielded a 23.2% effi-ciency with a 1.33 D/dm ratio. Superscript/Subscript Available更多