In order to solve the problem of dispersion transmission line power, Fourier sine series was used to represent electrical fast transient/burst (EFT/B). The RLCG models of twistedpair, single-line, double-line, and coaxial-cable were constructed based on the transmission line theory. Furthermore, with an application of superposition theorem, the propagation characteristics of broad band disturbance in long cables were analyzed. The results show that the disturbance voltage polarity and peak value continually changed with the increase of propagation distance. Twisted-pair and double-line had natural restrain function for EFT/B disturbance propagation in them since their voltages all attenuated to zero in load end of lkm. The disturbance voltage of coaxial-cable was the lowest in short distance, and its peak value fluctuated between positive and negative polarity in long distance. So, coaxial-cable was easily influenced by EFT/B. The disturbance voltage of single-line produced smart oscillation with the increase of propagation distance, and occurred 2. 5 times as high as EFT/B peak value in open-circuit. Finally, common mode interference was confirmed as the main form of EFT/B.%将电快速瞬变脉冲群(EFT/B)展开为傅里叶正弦级数,解决了色散传输线的激励加载问题.建立双绞线、单导线、双导线和同轴电缆的传输线模型,采用叠加原理分析宽带骚扰的传播特性,结果表明:骚扰电压极性会随着传播距离增大而不断转换,电压峰值在正负极性间呈振荡变化.双绞线和双导线对骚扰的传播具有自然抑制作用,长度为1 km时负载端的骚扰电压已衰减为0；同轴电缆在距离较短时骚扰电压峰值最低,距离较长时电压峰值会产生波动,带负载时正反向电压峰值都很大,长距离传输信号易受EFT/B的影响；单导线骚扰电压振荡最明显,且负载开路时会产生叠加效应,电压峰值最大可达激励源电压峰值的2.5倍,对地共模干扰是EFT/B的主要形式.
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