【摘要】 用电路法分析雷电流流经引下线时建筑物金属构架上的暂态感应电流分布,根据雷电流和金属构架上的感应电流产生的动态磁矢量位,利用差分法求解室内空间的暂态磁场分布.防雷引下线和建筑物金属构架的分段支路用全耦合的π型电路来模拟,并考虑频变特性和大地的镜像作用.验证了理论分析和计算的有效性,分析了这种建筑物遭雷击时的磁场分布特点.更多还原

【Abstract】 In buildings with separate external lightning down conductors, very high magnetic fields may occur in some area during a direct lightning stroke. Based on the circuit approach, this paper investigated the distribution of the magnetic fields in such buildings during the stroke. The lightning down conductor and the building’s metal framework branches are simulated by a series of coupled π-type circuits. The frequency-dependent performance of the circuit parameters and the effect of the earth were considered. The effectiveness of the simulations were evaluated on a scaled model of such building in laboratory through induced current and magnetic field measurements. Based on the analysis of the simulations, the characteristics of magnetic field distributions in such buildings under lightning strokes were disclosed.更多还原