架空传输线在间接雷击作用下负载浪涌的分析

传输线在雷击作用下浪涌的分析计算对电力线路的保护设计具有一定的指导意义，是电力系统电磁兼容研究的重要内容。文中引用了典型的雷电回击电流模型，先由傅立叶变换求得回击电流的频谱，根据传输线在外电磁场作用下的电路方程及相应的求负载端响应的BLT(Baum，Liu and Tesche)方程，在领域内求出传输线在间接雷击作用下负载端浪涌电压；然后，由傅立叶反变换求出负载端浪涌电压的瞬态解。分析了雷电落地点、雷电通道电流的传播速度及大地电导率等对负载浪涌电压峰值的影响。研究表明，大地电导率对浪涌电压的峰值和极性均有较大影响。

SURGE ANALYSIS ON LOAD OF TRANSMISSION LINE UNDER INDIRECT LIGHTNING STRIKE

Analysis of surge voltages on transmission line induced by nearby lightning return strokes can provide guidance for the protection design of transmission line. It is also the important aspect in the study of electromagnetic compati-bility in power system. Using a typical current of return stroke, the surge load voltage is calculated in two steps in this paper. Firstly, the current of return stroke in time domain is transferred into frequency domain, and according to the scattered voltage Telegraphers equations and the BLT(Baum,Liu and Tesche) equations, which are used to calculate the load responds, the induced load voltage is calculated in frequency domain. Secondly, the voltage is retransferred into time domain. The influence due to different stroke points,velocities of return stroke and ground conductivities are also studied.