Design and Comparison of Vertical DD Coil and Planar DD Coil for Wireless Charging System

With the rapid development of new energy electric vehicles (EVs) and the continuous advancement of wireless charging technology, high-power wireless charging technology for EVs has garnered significant attention. In existing research, DD coils are the most commonly used coil structure due to their high misalignment tolerance. This study proposes a vertical DD coil structure, which significantly reduces the horizontal footprint compared to planar DD coils while exhibiting superior performance in terms of magnetic flux density distribution and reduced magnetic field leakage. By establishing simulation models for both vertical and planar DD coils and conducting finite element analysis, the results show that the vertical DD coil provides better magnetic flux density distribution in the receiving area and has a smaller magnetic field leakage area, enhancing the overall efficiency of the wireless power transfer system. Additionally, the mutual inductance and coupling coefficient between the vertical DD coil and the receiving coil are slightly higher than those of the planar DD coil.