光电系统监测设备电磁屏蔽设计的系统法研究

Monitoring equipment's shield design used system method in optoelectronic system

某光电系统中监测设备需要满足GJB 151A-1997中陆军平台的电磁兼容指标要求,但在标准测试中,电场辐射测试结果超出RE102标准要求,为解决此问题,提出了监测设备的电场屏蔽系统设计方法,设计了电磁屏蔽结构并实施。首先,阐述了监测设备的RE102标准测试方法及测试结果。其次,在分析测试结果的基础上,提出了电磁屏蔽设计的技术指标,并从电磁兼容的系统设计法角度,提出了监测设备电磁屏蔽预设计的方法。最终,结合电磁屏蔽理论,对屏蔽箱体进行了设计,确定了箱体的材料、厚度及结构。针对孔缝等电磁屏蔽不连续结构,采用理论计算方法,在10kHz^30MHz频段内进行了屏蔽效能计算,分析了屏蔽加固的必要性,并对必须采用屏蔽加固措施的缝结构进行了设计。实验结果表明,施加电磁屏蔽措施后,监测设备通过RE102标准测试,且在305kHz频率处屏蔽效能为23.58dB,满足屏蔽设计指标要求。

Monitoring equipment of an optoelectronic system needed to meet GJB 151A--1997 ~s electromagnetic compati- bility requirements at army platform. However,in standard tests,electric field radiation test results exceed the standard requirements of RE102. To solve this problem, elaborated standard testing methods and test results of monitoring equip- ment. Secondly, based on analyze test results, proposed electromagnetic shielding design technical indicators, and from the perspective of EMC system design method. Finally, combined electromagnetic shielding theory, designed shielded enclo- sure, determined the cabinet material, thickness and structure. For discontinuous structure of shielding, by theoretical cal- culations,calculated shielding effectiveness in 10 kHz--30 MHz, analyzed the necessity of shielding reinforced,designed seam structure＇s shielding. The results showed that, after applying electromagnetic shielding measures, monitoring equip- ment meet the standard requirements of RE102,and shielding effectiveness is 23.58 dB at 305 kHz,meet shielding design requirements.