闪电回击工程模型的有效性研究  

Research on the Validity of Return Stroke Engineering Models

作　　者：陈亚洲[1] 王晓嘉[1] 万浩江[1] 

机构地区：[1]军械工程学院静电与电磁防护研究所,石家庄050003

出　　处：《高电压技术》2012年第10期2683-2690,共8页High Voltage Engineering

基　　金：国家自然科学基金(51077132)~~

摘　　要：为了分析几种常用的闪电回击工程模型的有效性,将回击通道底部电流表示为击穿电流和电晕电流的叠加,利用脉冲函数描述回击通道底部电流波形,选择了一种比较典型的回击通道底部电流波形参数,分别对Bruce-Golde(BG)模型、运动电流源(TCS)模型、Diendorfer-Uman(DU)模型、传输线(TL)模型、电流指数衰减的传输线(MTLE)模型和电流线性衰减的传输线(MTLL)模型6种回击工程模型产生的不同场区回击电磁场进行了计算,并将计算结果与实际测量得到的不同场区回击电磁场特征进行了比较。结果表明基于MTLL回击模型计算得到的不同场区回击电磁场能够符合实际测量回击电磁场所具有的4个特征:(1)电场与磁场都有1个快速上升的初始峰值,当观测距离>1km时该峰值的数值与距离接近成反比;(2)几十km距离以内的电场在起始峰值之后有1个缓慢的上升沿,其持续时间可长达100μs;(3)几十km距离以内的磁场在起始峰值后有1个隆起,其最大值在10～40μs之间;(4)50～100km距离之间的电磁场在初始峰值后几十μs内都有过零点。依据另外5种回击工程模型计算得到的回击电磁场不能与实际测量闪电回击电磁场的特征完全相符。因此,MTLL回击模型具有相对更高的精确度和有效性。In order to research the validity of the commonly used engineering return-stroke models,we calculated the electromagnetic fields reproduced by the Bruce-Golde（BG）,travelling current source（TCS）,Diendorfer-Uman（DU）,transmission line（TL）,modified transmission line model with exponential current decay with height（MTLE） and modified transmission line model with liner current decay with height（MTLL） models in different ranges from the lightning channel,respectively,in terms of specified channel-base current,moreover,we compared the calculated results with the field test ones.During the calculation,the division of the channel-base current pulse into the breakdown and corona current components was adopted,and the pulse function was chosen to describe the channel-base current.The results show that the MTLL model can reasonably reproduce the four characteristic features of the measured electromagnetic fields,e.g.,（1） the electric and magnetic fields have a sharp initial peak respectively of which the value approximately has an inverse ratio to the measuring distance when the distance is larger than 1 km,（2） the electric field within a few tens of km has a slow ramp which could last 100 μs after the initial peak,（3） the magnetic field within a few tens of km has a hump with its peak value at the time between 10 and 40 μs after the initial peak,and（4） both the electric and magnetic fields at the distance between 50~100 km have zero points within tens of μs after the initial peak.However,the other five engineering models can not provide good matches between their model-predicted electromagnetic fields and the measured data.Thus,it is concluded the MTLL model is accurate and the most suitable for the calculation of lightning electromagnetic field among the six methods.

关 键 词：闪电回击工程模型 回击电流分布 脉冲函数 回击电磁场 实测电磁场 有效性分析 

分 类 号：TM866[电气工程—高电压与绝缘技术]