基于传输线时域理论的同轴线中雷电波传播分析  

On the propagation of lightning wave in coaxial cable based on time-domain theory

作　　者：李祥超[1,2] 陈则煌[1] 周中山[1] 曹洪亮[1] 

机构地区：[1]南京信息工程大学中国气象局气溶胶与云降水重点开放试验室,南京2100442 [2]南京信息工程大学应用电磁学研究中心,南京210044

出　　处：《南京信息工程大学学报（自然科学版）》2016年第2期123-128,共6页Journal of Nanjing University of Information Science & Technology（Natural Science Edition）

基　　金：国家自然科学基金(41075025);南京信息工程大学大气科学与环境气象实验教学中心基金(SXJC2014A02)

摘　　要：针对雷电波在同轴线中传播特性的问题,通过对同轴线的暂态响应的理论分析,利用理论与试验相结合的方法,研究了同轴线对1.2/50μs雷电波的暂态响应.结果表明:线终端负载上的信号由所传输信号的频率成分以及波导终端阻抗性质决定;1.2/50μs雷电波信号频谱存在高于同轴线截止频率的成分,终端阻抗匹配情况下雷电波波头出现大量高次模成分;终端负载开路时,线终端信号的高次模是雷电波的入射波与反射波以及所激发的高次模之和;受雷电波频谱特征影响,雷电波激发出的高次模成分主要集中在波头部分;雷电波在线中传播的最终波形是各高次模分量之和,降低雷电波波头陡度可以减少高次模成分.在雷电过电压防护中应充分考虑到雷电波在线路中传播的畸变问题,这对于指导同轴线引入的过电压防护具有重要意义.In order to find out the propagation characteristics of lightning wave in coaxial cable,the transit response theory of coaxial cable was used to figure out the transit response to the 1？2/50μs lightning wave.Besides,the relat？ed experiment was carried out under the help of lightning current generator.The research results show：the terminal signals of the coaxial cable are determined by both features of signal frequency and terminal impedance;the high？or？der modes are caused by the refraction and reflection of lightning wave and its excitation when the terminal is opened;the high？order modes excited by lightning wave mainly concentrate on the wave front because of the influ？ence of the lightning wave spectrum;the final waveform at the terminal is the sum of all the high？order modes,and the lower of the lightning wave front the less of the high？order mode.The distortion of the lightning wave should be considered when propagating in coaxial cable,which has significance in guiding the suppression methods of overvolt？age in coaxial line.

关 键 词：雷电波 同轴线 暂态响应 高次模 过电压防护 

分 类 号：TM862[电气工程—高电压与绝缘技术]