Design and Analysis of Circular Coil Geometries for Wireless Power Transfer in Electric Vehicles The Effect of Multiple Coils at Primary and Secondary Sides

Abstract

Wireless power transfer (WPT) based on magnetic resonance is the technology that might isolate humans from wires. In practical terms, the WPT utilizes the same fundamental principle researched for at least half a century under inductive power transfer. In recent years, WPT technology has undergone tremendous development, with a grid-to-load efficiency greater than 90% and the transmission distance rises from a few millimeters to several hundred millimeters at kilowatt power levels. The advancements make the WPT particularly desirable for static and dynamic electric vehicle (EV) charging applications. This work designs and analyzes multiple circular coil geometries appropriate to EV wireless charging for the WPT application. Using ANSYS Maxwell software to simulate, construct and evaluate the performance of various coil assemblies, including coupling coefficient (k), Mutual inductance (M), self-inductance (L), and magnetic flux density (B) for air gap distance of 50mm to 200 mm. The coil dimensions have been the same for all coils, and the air gap length and the copper wire specifications are uniform for equality. Using the proposed multiple coil-based WPT in EVs may easily overcome charging time, range, and cost challenges.