FOREIGN OBJECT DETECTION IN WIRELESS POWER TRANSFER

Abstract

This project explores the phenomenon of Foreign Object Detection (FOD) in Wireless Power Transfer (WPT) systems with a particular emphasis on Metallic Object Detection (MOD) in Inductive Power Transfer (IPT) for applications such as electric vehicle charging. Although WPT enhances convenience and safety by minimizing physical connections, the presence of foreign objects inserted between the transmit and receive coils presents major issues, including efficiency loss, possible damage to objects, and safety hazards. This study introduces a sensor-based MOD system using a novel arrangement of sensing coils placed in close proximity to the transmitting coil. The detection principle is based on the examination of induced voltage changes across the symmetrical detection coils. The metallic object presence perturbs the magnetic field, inducing a detectable difference in induced voltage between the symmetrical coils. The report specifies the sensing coil design to be proposed, such as coil positioning and size, and the corresponding MOD circuit that is to be used to filter, amplify, and rectify induced voltage signals for safe detection by a microcontroller unit.