2019 Volume 43 Issue 6 Pages 125-132
To improve the fuel efficiency of electric vehicles, it is necessary to reduce the weight of the wireless power transfer coil in the vehicles. Resistance due to the skin effect or the proximity effect increases during wireless power transfer, decreasing the transmission efficiency. This study aims to reduce the weight of the coil by replacing it with an aluminum plate coil, which is easy to manufacture and inexpensive. The weight of the coil was reduced by 3/4 (from 1.9 to 0.44 kg) when compared with copper Litz wire. Furthermore, the AC resistance was reduced by applying magnetic coating to the same coil. Consequently, the transmission efficiency increased from 88.2% to 89.3%, an improvement of 1.1%. The optimal material for magnetic coating was revealed in an analysis.