Electromagnetic Radiated Emissions from a Wireless Power Transfer System using a Resonant Magnetic Field Coupling

Wireless power transfer technologies have been extensively researched for several decades and successfully deployed on a commercial scale. As studies on wireless power transfer technologies have progressed and its feasibility has been tested, electromagnetic radiated emissions have become more important subject than before. In this paper, we report the measurement and analysis of the electromagnetic radiated emissions from a wireless power transfer system using a resonant magnetic field. In this research, a relationship between the coil resonance and the transferred power are analyzed with respect to the impedance profile obtained from analytical expressions, simulations and measurements. As a result, it was demonstrated that the electromagnetic radiated emissions are enhanced at the series resonance peaks of the impedance profile in a wireless power transfer system using a resonant magnetic field coupling in the case of a constant-voltage AC source.