雷电电磁脉冲对便携计算机终端的损伤分析

目的使用电磁仿真软件XFDTD,研究雷电磁脉冲(LEMP)对便携计算机的电磁危害。方法给出腔体内部采样点处的电场时域波形图和截面的电场分布图,计算腔体内不同位置处的屏蔽效能和瞬时坡印廷矢量的大小,分析雷电电磁脉冲与腔体正面孔阵和侧面孔洞的耦合以及孔洞的互耦合。结果雷电电磁脉冲会与入射正面和侧面上的小孔发生不同程度的耦合。雷电电磁脉冲对腔体内部的电磁危害很小,电磁能量主要被限制在开孔附近,腔体中心处受到的影响最小。开孔面积越大,耦合进的电磁能量越多。相邻孔洞之间的互耦合效应使得腔体的屏蔽性变差。结论雷电电磁脉冲对便携计算机的危害一般很小。

Damage Analysis of Lightning Electromagnetic Pulse to Portable Computer Terminal

Objective To study electromagnetic hazards of lightning electromagnetic pulse (LEMP) on portable computers with electromagnetic simulation software XFDTD. Methods The time domain waveform of electric field at sampling point and the sectional view of electric-field distribution inside the cavity were given. The shielding effectiveness and the instantaneous Poynting vector in different positions in the cavity were calculated. The coupling of the lightning electromagnetic pulse with the front aperture array and the side hole of the cavity and the mutual coupling of holes were analyzed. Results The electromagnetic pulse of lightning caused coupling of different degrees to the small holes on the front and sides. Lightning electromagnetic pulse had little electromagnetic harm to inside part of the cavity. The electromagnetic energy was mainly confined to the neighboring of the open hole. The center of the cavity was affected least. The larger the aperture area was; the more electromagnetic energy was coupled. The mutual coupling effect between adjacent holes leaded to poor shielding effectiveness of the cavity. Conclusion Lightning electromagnetic pulses commonly do little harm to portable computers.