金属板屏蔽小室暂态磁场屏蔽效能的对比测试

介绍了一套测量屏蔽小室暂态磁场屏蔽效能的方法,源磁场为冲击电流在发射线圈中激励产生的暂态磁场,发射线圈和接收线圈同轴平行布置。比较开、关门时金属板小室所带3种可拆卸成型门对雷电波和两种频率的阻尼振荡波磁场的屏蔽效能及关门时侧壁对不同暂态磁场屏蔽效能的结果表明,金属板对不同强度暂态磁场的屏蔽效能基本恒定,不同材料结构的门对不同波形暂态磁场的屏蔽效能相差较大,关门后屏蔽效能会提高很多。

Contrast Measurement of Transient Magnetic Shielding Effectiveness of a Monolayer Metal Shielding Room

A method to measure transient magnetic shielding effec tiveness of monolayer shielding room is introduced. Transient magnetic is produc ed from the transmitting coil excited by impulse current. The transmitting and r eceiving coils are coaxially arranged. The transient shielding effectiveness of a shielding room with three different demountable doors is measured under lightn ing electromagnetic impulse and two different frequencies damped oscillation mag netic fields. The transient shielding effectiveness is compared while the door i s open or closed. At the same time the transient shielding effectiveness of the side wall of shielding room is measured while the door is closed. It shows that the shielding effectiveness of metal plate remains unchanged under different amp litude transient magnetic field. With different materials and structure, the shi elding effectiveness of doors varies a lot under transient magnetic with differe nt wave shapes. The shielding effectiveness can be improved significantly if the door is closed.