An investigation on electromagnetic shielding effectiveness of metallic enclosure depending on aperture position

Electromagnetic compatibility (EMC) become one of the most important topics during electric vehicle design due to incorporating high voltage systems into conventional vehicle electronic architecture. Electromagnetic shielding enclosure is a conductive barrier utilized for protecting electronic circuits against external electromagnetic interference (EMI). Shielding effectiveness (SE) is a measure of shielding performance for the enclosures. Aperture of the enclosures attenuate SE by permitting EMI leakage to affect the electronic circuits. In this study, the effect of aperture position on SE is investigated while the dimensions of the enclosure remain fixed. It is obtained that SE varies depending on the aperture positions and it gets better while aperture is closer to the corners of the front panel. Then, the effects of different observation points, the dimensions of enclosure and aperture on SE are analysed while keeping the aperture position at the corner. It is obtained that SE gets better when the observation point is located far away from the aperture. Enlarging the enclosure dimensions makes SE better while increasing aperture dimensions attenuates SE. Finally, it is concluded that it is crucial to consider aperture position, observation point, the dimensions of enclosure and aperture to obtain better SE.