Magnetic-Field-Model Based Analysis of Two-Phase Magnetically Coupled Resonant Wireless Power Transfer System

Wireless power transfer (WPT) that is essentially based on electromagnetic induction has been attracted increasing attention recently. Most of the previous work revealed that the transfer characteristics of the system would be greatly influenced by the spatial positions between the sending coils and the receiving coils. This paper focuses on a two-phase magnetically coupled resonant (MCR) WPT system, which incorporates two orthogonal sending coils excited by two equivalent ac sources with phase-shift angle control and a single receiving coil, and investigates the distribution of magnetic field around the sending coils under different angular misalignment of the receiving coil. The calculation of the magnitude of magnetic field, the induced voltage, and the output power are given in detail, along with the simulation verification by Maxwell. Finally, a prototype is built and tested to verify the theoretical analysis.