瞬态电磁场对屏蔽电缆的耦合机理  

Coupling Mechanism of Transient Electromagnetic Fields to Shielding Cables

作　　者：王一哲[1] 王泽忠[1] 柳华[2] 徐迪[2] 李云伟[1,2] 

机构地区：[1]华北电力大学电气工程学院,北京102206 [2]国核电力规划设计研究院,北京100032

出　　处：《高电压技术》2009年第8期1957-1962,共6页High Voltage Engineering

基　　金：国家杰出青年科学基金(50325723)~~

摘　　要：为了研究瞬态电磁场对屏蔽电缆的耦合机理,提出了区域分解时域有限差分法。基于法拉第定律的积分形式推导出了圆柱坐标系下三角形网格内磁场分量的FDTD差分方程,获得了屏蔽电缆不同截面上电磁场分布和屏蔽层上电流密度分布的规律。初步研究表明快速瞬态电磁场难以透过电缆屏蔽层耦合电缆芯线,缝隙耦合可能是瞬态电磁场耦合电缆的主要途径。In order to investigate the mechanism of transient electromagnetic field coupling to shield cable, domain decomposition finite difference time domain （DD-FDTD） algorithm was put forward. In the proposed method, on the basis of integral expression of Faraday law, FDTD discrete equation of magnetic component in triangle grid was deduced, and the simulating model was founded. The distribution law of all the electromagnetic field components on the different cross-section of the shielded cable and current density on the shield was achieved. The computed results show the amplitude of electromagentic field components in the end of the shielded cable is far greater than the one in the middle of the cable. With the radius decreasing, the current density on different columnar plane of the shield becomes small, current density on the outside surface is far greater than one on the inside surface of the shield. Ele- mentary investigation indicates that fast transient electromagnetic field is difficult to penetrate the shield of the cable; aperture is primary possible pass of transient electromagnetic field coupling to the core of the cable.

关 键 词：瞬态电磁场 屏蔽电缆 区域分解时域有限差分法 耦合机理 电磁干扰 电流密度 

分 类 号：TM154.1[电气工程—电工理论与新技术] TM564.1