Study On Shielding Effectiveness Of Shielding Case With Conductive Rubber

In recent years, with the rapid development of power electronics technology and electrical automation technology, the increasingly complex electromagnetic environment, the mutual interference between the growing of electronic equipment, the problem of EMC has become an important subject that not allow to ignore. In order to ensure the equipment is not subject to electromagnetic interference of the outside world, usually plus a metal shielding case on the equipment external, and because of the need to cooling, ventilation and other factors, inevitably requires opening slits on the case. External electromagnetic interference signals get inside the metal shielding case through these slits, affect the normal work of the equipment. The conductive gasket which is made of conductive rubber can greatly reduce the electromagnetic leakage brought by the slits on the metal shielding case. Therefore, the research of conductive rubber and the influence of conductive rubber on the shielding case is very meaningful.This paper combined with the principle of electromagnetic shielding and the typical structure of electronic equipment shielding case, compared the several electromagnetic leakage characteristics of shielding case, determined the slits on the shielding case is the most important source of electromagnetic leakage. In view of the slits on the metal shielding case, conductive rubber was introduced to suppress its electromagnetic leakage.Conductive rubber with the greatest impact on electromagnetic shielding effectiveness is its conductivity. So researched the two major factors influencing the conductive rubber conductivity: compression, electrochemical corrosion. This paper researched the conductive rubber compression and the relationship between the electrical conductivity, and then determined the conductive rubber electrochemical corrosion effect on the properties of conductive rubber.In view of the conductive rubber application in electronic equipment shielding case, divided into two aspects to research. On one hand, obtained by the compression of conductive rubber shielding casing deformation caused by the effect of shielding effectiveness for shielding case as a whole, when calculating the shielding effectiveness,combined the conductive rubber's compression and its conductivity, the shielding effectiveness of the simulation calculation model is optimized; On the other hand, the shielding case application of electrochemical corrosion phenomenon of conductive rubber effects on electromagnetic shielding effectiveness of whole.