A Comparative Study of Rectangular and Double- D Coil Geometries for the Inductive Link Design of Wireless EV Charging System

The performance of the magnetic couplers in an inductive power transfer system determines the overall feasibility of an entire system. In this paper, the basic theory behind wireless power transfer and the required components is analyzed, showing how design aspects, power pad physical dimensions, height and vertical displacement affect the results. Two coil geometries are analyzed and investigated in this work and their coupling characteristics and misalignment tolerance are studied and compared. This study aims at the design and Finite Element Modeling (FEM) simulations of the inductive link to maximize Figure-of-merit (kQ) and improve misalignment tolerance. Based on the simulation results, the geometry in which Double D coils are considered for primary and secondary charging pads provides the highest coupling factor and highest inductive link efficiency at various misalignment conditions up to + / - 800 mm, and up to 30 cm air gap.