Novel Dynamic Wireless Power Transfer System for Battery Electric Vehicles Using In-Tire and In-Wheel Repeater Coil

In order to improve the mileage per charge of battery electric vehicles, dynamic wireless power transfer systems are being developed. There are some problems, such as are the wide gap between coils when mounted under the floor of a vehicle and the effect of foreign metal objects between coils during power transmission. In-wheel coil, which is a receiver coil and placed inside a wheel, have been proposed to solve the above problems. However, the wheel should be made of non-metal because large eddy current loss occurs. In addition, the gap is still large. In this paper, we propose a coil configuration in which the coils are placed inside the tire and the wheel. This method has the advantage that the conventional aluminum wheel can be used while reducing the gap between coils. The effectiveness of this method is demonstrated by simulations and experiments.