基于斜向放电通道的地表雷电电磁场特性分析  

Characteristics Analysis of Surficial Lightning Electromagnetic Field for Oblique Discharge Channel

作　　者：陈亚洲[1] 王晓嘉[1] 万浩江[1] 王琳[1,2] 

机构地区：[1]军械工程学院静电与电磁防护研究所 [2]77108部队

出　　处：《高电压技术》2012年第11期2805-2814,共10页High Voltage Engineering

基　　金：国家自然科学基金(51077132)~~

摘　　要：为保护敏感设备免受雷电电磁脉冲场的危害并选择合适的防护措施,需要确定斜向放电通道下雷电回击电磁场的场强以及分布规律。为此,将雷电斜向放电通道的电流微元分解为垂直和平行于大地的分量。利用脉冲函数表示通道底部电流,结合回击电磁场的传输线模型,根据偶极子法求解Maxwell方程组,得到了斜向通道在空间产生电场与磁场的解析表达式。进而研究了通道倾斜程度对不同场区地表回击电磁场的影响以及回击电磁场随观测点位置的变化规律。结果表明:地表电场比磁场更易受到通道倾斜程度和观测点位置的影响,且地表电磁场强度波形峰值在近场、中间场和远场均随斜向通道与地面夹角的增大而减小,在远场和中间场随斜向通道与地面观测点之间方位夹角的增大而减小。In order to protect sensitive equipment from the harm of lightning electromagnetic pulse（LEMP）and to choose appropriate protective measures,it is necessary to know the distribution law of lightning electromagnetic field in the oblique lightning discharge channel.In this paper,the infinitesimal current of lightning channel is decomposed into the perpendicular component and the horizontal component.By employing the pulse function to express the channel-base current and the transmission line model to describe the lightning return stroke process,the analytical expressions of electric and magnetic field generated by the oblique channel is obtained based on the dipole method and Maxwell equations.Then the electromagnetic fields on earth surface of lightings having different inclined angles between the channel and the ground at different positions of the observation point are calculated.The results show that the influences of the channel inclination and the observation positions on the electric field are greater than that on the magnetic field.Moreover,the peak value of the electromagnetic field waveform in the tilting side decrease with the increasing of the inclined angle between the channel and the ground in near area,intermediate area and far area,and decrease with the increasing of the horizontal azimuth angle between the oblique channel and the observation point in intermediate area and far area.

关 键 词：雷电回击电磁场 斜向放电通道 偶极子法 脉冲函数 地表电磁场 回击模型 

分 类 号：TM861[电气工程—高电压与绝缘技术]