A Near Field Analytical Model for EMI Reduction and Efficiency Enhancement using an Nth Harmonic Frequency Shielding Coil in a Loosely Coupled Automotive WPT System


In this article, we propose a near field analytical model of an electromagnetic interference reduction method using an nth harmonic frequency shielding coil with efficiency enhancement in a loosely coupled automotive wireless power transfer system. In general, in the loosely coupled automotive wireless power transfer system, the power transfer efficiency is relatively lower than a tightly coupled wireless power transfer system due to the low coupling. In addition, the electromagnetic interference at the nth harmonic frequency from the power source can interfere with nearby electronic devices. To reduce electromagnetic interference level and enhance efficiency, we proposed a shielding coil between a transmitter and a receiver coil. By using a near field analytical model of the magnetic field intensity and efficiency equations, we analyze based on the equations and obtain a proper value of the resonant frequency of the shielding coil. Therefore, we can achieve low levels of electromagnetic interference at the specific nth harmonic frequency and higher value of the power transfer efficiency in the loosely coupled automotive wireless power transfer system.


Electrical and Computer Engineering

Research Center/Lab(s)

Electromagnetic Compatibility (EMC) Laboratory


Ministry of Science, ICT and Future Planning, Grant IITP-2019-2016-0-00291

Keywords and Phrases

Automotive Electromagnetic Compatibility (EMC); Electromagnetic Interference (EMI); EMC; Harmonic Frequency (HF); Resonant Frequency; Shielding; Wireless Power Transfer (WPT)

International Standard Serial Number (ISSN)

1558-187X; 0018-9375

Document Type

Article - Journal

Document Version


File Type





© 2021 Institute of Electrical and Electronics Engineers (IEEE), All rights reserved.

Publication Date

01 Jun 2021