Coupled mode theory and equivalent circuit model were used to conduct a theoretical analysis of a typical magnetic resonance wireless power transmission system, and the theoretical relationship between transmission efficiency and coupling coefficient between resonant coils was obtained. The Maxwell simulation platform was used to construct a closed coil model, coil's parameter was scanned, and resonant coil was simulated and analyzed, and the influence of the coil's structural parameters (including the number of coil turns, turn spacing, and inner diameter) and the spatial distance between coils on the system transmission efficiency were obtained. The results show that increasing the number of coil turns can effectively improve the system transmission efficiency. The optimal turn spacing and inner diameter of the coil maximize the system transmission efficiency. Appropriate changes in the spatial distance between coils have a significant impact on the system transmission efficiency. The analysis results can provide a theoretical basis for subsequent optimization of magnetic resonance coils.
Kurs A, Karalis A, Moffatt R, Joannopoulos JD, Fisher P, Soljacic M. Wireless power transfer via strongly coupled magnetic resonances[J] . Science,2007,317:83.