不同电磁脉冲作用下地面有限长电缆外导体感应电流的数值计算

 运用时域有限差分法计算了地面有限长电缆在高功率微波、超宽带和核电磁脉冲作用下的外导体感应电流。计算结果表明：场强相同情况下，核电磁脉冲在电缆上感应的电流最大，持续时间最长，高功率微波和超宽带在几m长和几十m长的电缆上感应的电流相差不大；入射角对电缆感应电流也有影响，电场方向与电缆平行时感应最强；地面电缆的感应电流振荡频率比自由空间中电缆的感应电流振荡频率低；随着大地电导率的增大，感应电流反射波衰减加快；电缆任一端接地后，接地端电缆感应电流都会增大。

Simulation of different electromagnetic pulse coupling to the finite cable near ground

In this paper, the induced current in the finite cable near ground is calculated by FDTD method when exposed to HEMP,HPM and UWB pulse respectively. The numerical results indicate that the induced current varies with the length of cable, incident angle and the conductivity of ground. With the same electric field intensity, the HEMP induced current is the largest one among the three induced currents. There's almost no comparable difference between the induced currents in the 5m and 20m cable when exposed to HPM and UWB pulse. The larger the conductivity of ground is, the more quickly the induced current attenuates. When the cable is grounded at one end the current at the grounded end will increase.