Vertical Receiver Coils for Improved Energy Transfer Efficiency in Dynamic Wireless Charging of Electric Vehicles

This paper proposes a novel receiver coil configuration referred to as the Vertical Coil (VC), which substantially improves energy transfer efficiency in Dynamic Wireless Power Transfer (DWPT) systems for electric vehicles (EVs). Unlike the commonly used horizontally oriented coil layout (DDQ), the VC design employs multiple coils wound vertically around a ferrite core, thereby capturing magnetic flux more effectively over an extended spatial range. Through comprehensive simulations on full-scale models and corroborating small bench model experiments, we demonstrate that the VC configuration not only achieves a higher peak efficiency exceeding 90% but also widens the efficient power transfer zone by approximately 50% compared to DDQ. This broader coverage translates into an overall energy capture increase of more than 50% during a full pass of the vehicle over the transmitter coils, a significant step toward facilitating the implementation of DWPT technology. While mutual coupling among the VC coils can alter the system’s resonance frequency, our results confirm that this effect does not impede the VC’s superior energy transfer performance. Consequently, the new VC receiver design offers a promising pathway for advancing DWPT technology for reducing EV battery size and extending driving range.