电子控制设备电磁屏蔽仿真研究

发布时间：2018-05-13 14:45

本文选题：电磁兼容 + 有限元法　；参考：《河北科技大学》2015年硕士论文

【摘要】：随着电子产品的日益更新,以及数字系统工作频率的日趋提高,电磁兼容问题也变得更加突出,而电磁屏蔽作为电子设备设计的一项重要内容,也越来越引起技术人员的关注。首先分析了电磁屏蔽机理,讨论了几种目前应用于电磁耦合问题的电磁场数值计算方法,然后使用基于有限元法编制的Ansoft软件分别对电子设备外部屏蔽机箱及内部PCB的屏蔽效能进行了模拟仿真分析,为电子设备机箱的屏蔽设计及PCB板的合理布局提供一定的参考。完成的主要工作有:1)以带孔的电子屏蔽箱体为对象,采用Ansoft HFSS软件研究了在外部源的干扰下孔的形状、尺寸、厚度及数量对屏蔽体屏蔽效能的影响,得出了影响带孔腔体屏蔽特性的关键因素和一般规律。2)以带缝隙的电子屏蔽箱体为对象,应用有限元法研究了缝隙的长度、数量、方位等对腔体屏蔽特性的影响,得出了影响腔体屏蔽特性的主要因素和一般规律。3)以电子设备内部的PCB板为对象,对PCB板中高频干扰带来的电磁兼容问题进行了仿真分析。首先采用软件SIwave分析了裸板的谐振情况,指明了谐振分析在电路设计中的重要性。然后采用软件Cadence与Ansoft SIwave相结合的方式得到PCB近场图,为PCB的电磁兼容性设计提供数据支持。4)以辐射强度较大的0.9GHz近场图为参考依据,通过调整敏感元件、信号线、高频激励走线的位置以及走线之间的宽度来改善PCB的电磁兼容性能,为PCB板的前提布局设计提供一定的参考依据。
[Abstract]:With the updating of electronic products and the increasing frequency of digital system, the problem of electromagnetic compatibility becomes more and more prominent. As an important part of electronic equipment design, electromagnetic shielding has attracted more and more attention of technicians. Firstly, the mechanism of electromagnetic shielding is analyzed, and several numerical calculation methods of electromagnetic field which are used in electromagnetic coupling problem are discussed. Then the Ansoft software based on finite element method is used to simulate and analyze the shielding effectiveness of external shielding case and internal PCB of electronic equipment, which provides a certain reference for the shielding design of electronic equipment chassis and the reasonable layout of PCB board. The main work accomplished is: (1) taking the electronic shielding box with holes as the object, the effects of the shape, size, thickness and quantity of the holes on the shielding effectiveness of the shielding body under the interference of external sources are studied by using Ansoft HFSS software. It is concluded that the key factors and general rules affecting the shielding characteristics of the cavity with holes are as follows: (2) the effects of the length, quantity and orientation of the slot on the shielding characteristics of the cavity are studied by using the finite element method, taking the electronic shielding box with the slot as the object. The main factors affecting the shielding characteristics of the cavity and the general rule. 3) taking the PCB board inside the electronic equipment as the object, the electromagnetic compatibility problem caused by the high frequency interference in the PCB board is simulated and analyzed. Firstly, the resonance of bare plate is analyzed by software SIwave, and the importance of resonance analysis in circuit design is pointed out. Then the near field diagram of PCB is obtained by combining software Cadence and Ansoft SIwave, which provides data support for the design of EMC of PCB. 4) based on the 0.9GHz near field diagram with high radiation intensity, the sensitive element and signal line are adjusted. In order to improve the EMC performance of PCB, the position of high frequency excitation line and the width between lines can be improved, which provides a certain reference for the design of PCB board's premise layout.
【学位授予单位】：河北科技大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TN03

【参考文献】