贯通导线对腔体内电路电磁干扰影响的仿真研究

Simulation of Circuit Electromagnetic Interference by a Wire Penetrated a Shielding Box

研究了无贯通导线时干扰源发出的电磁脉冲波通过贯通孔耦合进入屏蔽体内对印制电路板终端负载产生干扰电压,并仿真了干扰源与线之间的距离以及线长度变化时对电压产生的影响。研究表明贯通导线通过与屏蔽体外的电磁脉冲波耦合,可使传入进屏蔽体内印制电路板终端负载电压增大很多,同时随着导线与干扰源距离的缩短终端负载干扰越大,而线的长度变化时,终端负载干扰电压与线和干扰源的相对位置有关,低频时相对位置对称干扰大,高频时随着相对位置不对称性增大其干扰增大。这些工作对电子系统的设计和安装具有指导意义。

In this paper, we studied the voltage produced by electromagnetic pulse wave which is radiated from an interference source passing through a gap to enter a shielding box. Then, we simulate the result by changing the wire length and the distance between the interference source and the wire. It turns out that the shorter the distance, the bigger the interference. When the wire length changes, we find that the terminal load interference voltage has a connection with the relative position between the wire and the interference source. Further study shows that with low frequency, interference is much bigger when given symmetrical relative position. While with high frequency, situation just becomes the opposite. After all, we are confident that these researches will benefit the electronic system design and installment.