Downsizing of High-Power Open-end Coil with Pure Water

This paper proposes an open-end coil using pure water to reduce the size of the high-power coupler used in the Inductive Power Transfer system. A conventional open-end coil tends to have larger size at lower operating frequency. On the other hand, the proposed open-end coil uses pure water with high dielectric constant to achieve lower operating frequency and higher power without changing the coil size. First, the features and structure of the proposed coil are described. Next, the proposed open-end coil is evaluated using the finite element method. The results show that a factor of about 1/3 reduces the operating frequency compared to the conventional type.