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Modeling and characterization of PCB coils for inductive wireless charging

  • Brian Curran (a1), Uwe Maaß (a1), Gerhard Fotheringham (a2), Nobby Stevens (a3), Ivan Ndip (a2) and Klaus-Dieter Lang (a1) (a2)...


Wireless charging is emerging as a viable technology in many industries, including consumer, medical, and sensor electronics. An investigation of design principles is conducted for a wireless charging platform that is designed to charge devices of different sizes and technologies, using only through vias. It is shown that at a 5 mm separation distance, a coupling coefficient can be achieved which varies from 0.12 to 0.37 when staggered hexagonal transmitter coils (approximately 5 cm across) are used with an unstaggered square receiver coil, which declines to 0.06–0.11 at 2 cm separation. Without design measures, the coupling coefficient will approach zero at certain positions. The quality factors of the coils can be improved by stacking the coils in parallel, enabling the use of only through-vias, while the inductance can be controlled horizontally by increasing the number of turns in the inductor.


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Corresponding author: B. Curran Email:


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