Open AccessReceiving‐coil structure reducing stray AC resistance for resonant coupling wireless power transfer
Author(s) -
Umetani Kazuhiro,
Honjo Toru,
Koyama Takahiro,
Ishihara Masataka,
Hiraki Eiji
Publication year - 2019
Publication title -
iet power electronics
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.637
H-Index - 77
eISSN - 1755-4543
pISSN - 1755-4535
DOI - 10.1049/iet-pel.2018.5358
Subject(s) - inductance , electromagnetic coil , wireless power transfer , maximum power transfer theorem , electrical engineering , power (physics) , coupling (piping) , inductive coupling , materials science , engineering , electronic engineering , mechanical engineering , voltage , physics , quantum mechanics
Resonant inductive coupling wireless power transfer is widely known to be a possible convenient power supply method for the small mobile apparatus. However, the limited receiving‐coil size tends to lower the efficiency and limit the output power owing to the small mutual inductance and comparatively large stray alternating current (AC) resistance of the receiving‐coil. This study mitigates this issue by proposing a novel receiving‐coil structure. This proposed structure comprises a coil and a drum core with a thin axis. The coil is wound on the axis to form a single winding layer. The proposed structure can reduce stray AC resistance by suppressing the proximity effect and reducing the wire length without deteriorating the mutual inductance significantly. Therefore, better efficiency and larger output power can be achieved. Simulations and experiments were performed to verify the proposed structure. Consequently, both simulations and experiments supported the reduction in AC resistance compared to the conventional structure. Furthermore, the experiment revealed improvements by the proposed structure in both efficiency and output power. These results support the effectiveness of the proposed structure for wireless power transfer to small mobile apparatus.