On the Utilization of Double-D Quadrature Coils in Dynamic Wireless Electric Vehicle Charging Systems

With the increasing interest in electrified transportation systems, dynamic wireless EV charging (DWC) systems offer several advantages over static charging as they eliminate EV charging downtime and offer on-the-move EV charging services. Nevertheless, the inherent misalignments during the vehicle's motion impact the coupling performance of the wireless inductive link and reduce the power received by the EV from wireless charging. Several coil design enhancements can be adopted to improve the misalignment tolerance of DWC systems. In this work, the addition of a quadrature component on the secondary charging pad is investigated and the performance of the resulting double-D quadrature coil is evaluated against that of a stand alone DD coil. Simulations reveal an improvement in the misalignment tolerance range when the quadrature coil is utilized, as long as the current flow direction is matched between the secondary Q coil and the coupled rectangular portion of the primary DD coil. This needs to be further enhanced through the design of power and current control loops, as well as optimization of quadrature coil design and placement, for improved misalignment performance.