Research on Effective Coupling Range of Medium Distance Wireless Power Transfer via Coupled Magnetic Resonances

As a branch of the wireless power transmission technology, Wireless Power Transfer via Coupled Magnetic Resonances system can achieve high-power and high-efficiency medium-distance power transmission. However, in the system space, not all spatial points can achieve effective energy transmission, and the transmission efficiency of the system is deeply affected by the change of coil position. This problem has became one of the bottlenecks restricting the development of this technology. Aiming at the above problems, we can build a model of Wireless Power Transfer system by using circuit theory. It’s easy to know the expression of system receiving power and transmission efficiency with the model. At the same time, the effective coupling range of the system can be defined by simulation analysis. Finally, the finite element model and experimental system are built to verify the theoretical analysis. The experimental results are in good agreement with the theoretical analysis. The system transmission power can reach more than 80% of the critical coupling power within the effective coupling range. The results not only prove the correctness of the proposed method, but also provide a beneficial reference for Wireless Power Transfer via Coupled Magnetic Resonances system optimization.