AN EFFICIENT METHOD FOR DIMENSIONING MAGNETIC SHIELDING FOR AN INDUCTION ELECTRIC VEHICLE CHARGING SYSTEM

Abstract

Recently, the number of electric vehicles (EVs) is increasing due to the declining of oil resources and rising of greenhouse gas emission. However, EVs have not received wide acceptance by consumers due to the limitations of the stored energy and charging problems in batteries. The dynamic or in motion charging solution becomes a suitable choice to solve the battery related issues. Many researchers and vehicle manufacturers are working to develop an efficient charging system for EVs which is based on magnetic emissions to transfer power. These emissions must be evaluated and compared to limits specified by standards (in and outside the vehicle) in order to not cause harmful effects on their environment (humans, pets, electronic devices...). This paper presents an efficient method for modeling electromagnetic emission in near field and sizing a magnetic shield for a wireless power transfer (WPT) system for EVs. A model based on elementary magnetic dipoles is developed in order to obtain the same radiation as the real WPT coil. This model is used to size a magnetic shield which will be placed under the vehicle to protect human body from magnetic emissions. The obtained shielding plate allows to respect the standards of magnetic emission by bringing a decrease of 43 dB to the levels of magnetic fields. This approach is experimentally validated.