摘要
在研究电力电缆发生短路对周围通讯系统的危险影响时，短路电流的分布和入地电流系数的计算是至关重要的。这必然涉及线路阻抗、相序阻抗和自互阻抗等参数。文章给出了电缆线芯不换位、金属护套交叉互联两端接地系统的线路阻抗矩阵、相序阻抗矩阵的直观表达式；分析了它们的一些性质。介绍了隧道中电缆参数的一种分析方法，即虚拟媒质法。应用该法可以方便地处理隧道空气区对其自互阻抗的影响。由于该法是数值方法，隧道横截面形状可以任意。
In the investigation of the damage effects to communication lines caused by short circuit failure of power transmission cables, it is essential to calculate the distribution of the short circuit current and the current emanating to the earth. In the calculation the parameters of the cable must be determined first, including the line impedance, phase sequence impedance, self and mutual impedance. In this paper a plain expression of a line impedance matrix and phase sequence impedance matrix is presented to express the two ends earthing transmission cable system with the intersect connection of cable sheath but non transposition of the cable core. An approach is presented to analyze the parameters of cables located in underground tunnel, which introduces a fictitious conducting medium in the tunnel. With this approach the influence of the air region of the tunnel on the impedance of cables can be analyzed conveniently by numerical techniques, and tunnels with arbitrary section configurations can be simulated.
出处
《电网技术》
EI
CSCD
北大核心
1998年第9期5-8,共4页
Power System Technology
关键词
地下电力电缆
电缆
阻抗
回流系数
短路
矩阵
Underground power cable Cable tunnel Impedance Factor of back flow current
