Simulation of Shielding Effectiveness in Low Frequencies for Conductive Enclosure

Electromagnetic pulses are fields of energy that they can damage electrical and electronic circuits at once. New technology of microelectronic circuits is sensitive to interference power. An intentional or inadvertent risk and unforeseen create irreparable damages, so that it is important to investigate electromagnetic interference from viewpoint: generation source, the effectiveness on¬ electronic components and safekeeping methods. One of the prevalent methods for safekeeping against these pulses is shielding. In this paper, at first, the effect of magnetic field intensity is investigated in frequency selected (0-545 Hz) for various shields such as: paramagnetic materials, diamagnetic materials and ferromagnetic materials and shielding effectiveness was calculated for various low frequencies in one point in shield and shielding effectiveness changing with frequency changing for any material was obtained. In The following of paper, the effect of magnetic field intensity is investigated on shield's two apertures and six apertures with frequency changing. Then, the apertures were displaced on shield surface and were obtained shielding effectiveness changing. This apertures displacement has done for various shield materials. Finally, the effects of composite shields were investigated to shielding effectiveness. These shields have combined to two materials. We obtained interesting results from composite shields. In this paper, solution method has chosen 2DFEM and the whole of simulations have done Cosmos/M.