Coil Design for a 3.7kW WPT Electric Vehicle Charger

In recent times, one of the most promising research areas in EV technology is Wireless power transfer (WPT). It has the potential to solve few drawbacks of the current EV technology such as conductive charging with awkwardly long orange colored high voltage chords, limited battery endurance, range anxiety and lack of charging infrastructure facilities [1–5]. Various Circuit formulations like inductive or capacitive or magnetic resonance coupling techniques have been proposed for WPT. These various techniques try to transfer power within a couple of centimeters using either basic topologies like Series-Series, Series-Parallel, Parallel- Series and Parallel-Parallel or Hybrid topologies (LCC, LCCL, LLC etc) [6–9]. This paper discusses magnetic Resonance technique based WPT system mainly for Circular, Square and Bipolar Coil Structures (Rectangle in Geometry). This paper gives step by step guidance for coil design for three different coil structures to transfer 3.7 kW of power across 180 mm distance. A novel WPT charger will be proposed by comparing the results obtained from the analysis of three different coil structures. The various coil structures are studied by finite element method (FEM) using Ansys Electromagnetics and circuit analysis are done using Simplorer. This is a comprehensive analysis, where each coil configurations are analyzed as bare coils, with ferrites and with ferrites and shielding techniques. The results are compared, and an optimized design is proposed towards charging Electric Vehicles Wirelessly.