NEW SURGE SIMULATOR BASED ON NUMERICAL ELECTROMAGNETIC FIELD CALCULATION

本计画的目的是发展一种能在频域中利用矩量法分析喘振现象的方法。天线和微波电路的分析方法是在同一频率范围内处理频率响应，而时间响应在浪涌分析中是很重要的，通常通过傅立叶逆变换得到。由于许多频率响应必须计算的变换，大量的计算时间是必要的。针对传统的浪涌模拟器EMTP，建立了传输线频域的等效电路模型，采用矩量法对传输线的频率响应进行了数值计算，并通过解析方程建立了传输线频域的等效电路模型。该方程是无理函数，但通过Pade近似和EMTP中Marti模型的适当形式，可以转化为有理函数，并将该模型应用于输电线路杆塔的回火分析，计算值与实测值吻合较好。

The project aimed to develop the method which can analyze surge phenomena in frequency domain by Moment Method. The method in analysis of Antenna and Micro Wave circuits deals the frequency response in same frequency area, but the time response is important in surge analysis and obtained by inverse Fourier transformation. As many frequency responses must be computed for the transformation, large computing time is needed. But if many work stations can be used at the same time, the computing time decrease by the parallel processing.The equivalent circuit model of transmission line frequency domain are investigated for the conventional surge simulator EMTP.Moment method is applied to obtain the frequency response numerically and formed the model by analytical equation. The equation is the irrational s functions but can be transformed to rational function by the pade apporoximation and suitable form to the J.Marti model in EMTP.We applied the model to the back flash over analysis with transmission line tower and close agreement between observed and calculated values was obtained.