A Parameter Design Method for a Wireless Power Transmission System with a Uniform Magnetic Field

Abstract

In a wireless power transfer (WPT) system, misalignment on the transceiver side has a major impact on the transmission efficiency. However, a uniform magnetic field can mitigate the detrimental impact of offsets on the system performance. In this paper, an optimized double-D (DD) coil is proposed by dividing the wires into two groups. The parametric design approach proceeds from the outside to the inside of the coil. The uniformity of the magnetic field of the improved design is increased by 20.7% compared to that of a regular DD coil. The average transmission efficiency of the final test prototype can reach 85%, and the offset rates in the X and Y directions are only 3.21% and 3.43%, respectively, when misalignment occurs. This design can effectively improve the anti-offset ability of the system and can be generalized to the design of other types of coils.