Influence of magnetic design choices on the quality factor of off-the-shelf wireless power transmitter and receiver coils

In the design process of inductive wireless power systems, the quality factors of transmitter and receiver coils play an important role in the optimization of the link efficiency. In this work, the experimental evaluation of the quality factor of several commercially available transmitter and receiver coils is performed. The influence on the Q-factor of the following design choices is evaluated: an alignment aid magnet in the transmitter coil, the presence of ferrite at the receiver coil, electrical screening at both the transmitter and receiver coil and finally the effect of the proximity of the transmitter and receiver. The results of this research provide a clear overview of the impact of the studied magnetic design choices.