DESIGN OF WIRELESS POWER TRANSFER COILS FOR ELECTRIC VEHICLES AND ANALYSING THE COUPLING COEFFICIENT ACCORDING TO THE CHANGING COIL INNER DIAMETER

Year 2025, Volume: 13 Issue: 4, 1264 - 1278, 01.12.2025

Yasin Akün , Abdülsamed Tabak

https://doi.org/10.36306/konjes.1703287

Abstract

The popularity of electric vehicles (EVs) is steadily increasing, and their adoption is becoming more widespread. This growing prevalence has led to increased interest in wireless and contactless charging systems for EVs as alternatives to traditional wired methods. Consequently, it is essential to analyse the factors that affect the efficiency of wireless power transfer (WPT). In WPT systems, a primary coil is installed at the charging station, while a secondary coil is positioned beneath the vehicle. Power transmission occurs due to the magnetic field generated between these two coils. One of the key factors influencing the efficiency of WPT is the coupling coefficient. This study examines the impact of variations in the inner diameters of identically designed primary and secondary coils on the coupling coefficient. The analysis was performed using the ANSYS Electronics – Maxwell 3D simulation tool. The results indicate that increasing the inner diameter of the coils from 50 mm to 300 mm leads to a 69.23% increase in the coupling coefficient. This study offers an original contribution by systematically analysing the impact of varying inner coil diameters on the coupling coefficient in coaxial WPT systems, a topic not yet thoroughly addressed in the existing literature.

Keywords

ANSYS Maxwell 3D , Coil Design , Coupling Coefficient , Electric Vehicles (EVs) , Wireless Power Transfer (WPT)

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