Optimized Design of the DD Coil for Improved Misalignment Tolerance

The double-D (DD) coupling coils are widely used in different inductively coupled power transfer (ICPT) systems. In this paper, the impacts of the spacing between the ferrite bars, and the number of turns and layers on the edges of the coil on the misalignment tolerance of the DD coupling mechanism are investigated. Based on the simulation results calculated from the finite element analytical model, several helpful design guidelines can be concluded to improve the misalignment tolerance of the DD coupling coil. And an optimized DD coil is presented to verify the effectiveness of the proposed design guidelines. Compared with the original DD coil, the fluctuation of the coupling factor of the optimized one is reduced from 42.4% to 25.8%, when the system has a 200 mm offset in the X-direction.