单端接地屏蔽电缆低频耦合干扰分析与仿真  

Analysis and Simulation of Low-frequency Coupling Interference of Single-ended Grounding Shield Cable

作　　者：杜辉[1] 朱峰[2] 李鑫[2] 

机构地区：[1]中国民用航空总局第二研究所 [2]西南交通大学电气工程学院

出　　处：《安全与电磁兼容》2017年第5期54-57,共4页Safety & EMC

摘　　要：为分析线路单端接地时的信号低频干扰问题,基于有限元软件Ansys分析了屏蔽层周围空间的电磁场分布,以及地表电位对芯线串扰电压的影响,通过仿真求得了多导体系统的耦合电容,建立了低频信号下传输线的电路模型。分析了屏蔽层电位、屏蔽层与两芯线耦合电容的差值、信号源输出阻抗对芯线串扰电压的影响,给出了线缆串扰电压的计算公式,并对比了一起轻型轨道衡工频干扰事故的实测数据,验证了理论的正确性。To analyze the low frequency interference problem of single-ended grounding, the electromagnetic fieht distribution around the shielding space is analyzed based on finite element software ANSYS as well as the influences of surface potential on the crosstalk voltage of the core. The coupling capacitance of the multi-conductor system is obtained by simulation, and a low-frequency signal transmission line circuit model is established. The influence of the shielding potential, the difference between the shielding layer and the two-core coupling capacitance, and the output impedance of the signal source on the crosstalk voltage of the cable are analyzed, by which the calculation formula of the cable crosstalk voltage is given. Compared with the measured data of power frequency interference in a light rail accident, the correctness of the circuit model is verified. The research rcsuhs can provide a data reference for solving the problem of low frequency interference.

关 键 词：低频干扰 屏蔽线缆 线缆串扰 电容耦合 

分 类 号：TN03[电子电信—物理电子学]