屏蔽对电子设备EMC性能影响分析

摘要

针对电磁兼容（Electromagnetic Compatibility,EMC）测试标准对电子设备机箱屏蔽效能的需求,首先从屏蔽机箱的反射损耗与吸收损耗等方面入手,分析了屏蔽机箱的屏蔽效能,描述了如何根据实际使用情况对屏蔽机箱的材料及其厚度进行选择。根据屏蔽机箱实际使用情况,分析了孔洞和缝隙对其屏蔽效能的影响。结合2个电子设备的EMC测试实例,分别描述了如何对屏蔽机箱上的孔洞和缝隙进行处理,从而提高设备的EMC性能。分析并讨论了如何在设计阶段采取措施,通过加强屏蔽,改善设备的EMC性能。%Aiming at the requirement for shielding effectiveness of shielding case of electronic devices of electromagnetic compatibility（EMC） testing standard,this paper firstly analyzes the shielding effectiveness of shielding case and describes how to select the material and its thickness of shielding case based on the practicality by analyzing the reflection loss and absorption loss of shielding case.In addition,the influence of holes and gaps on the shielding effectiveness of shielding case is analyzed.Combining with two EMC testing examples,this paper analyzes how to handle the holes and gaps of shielding case to improve the EMC of electronic devices.Finally,the paper analyzes and discusses how to improve the EMC of electronic devices by strengthening the shielding effectiveness of shielding case in the design phase.