抑制继电保护测试信号源非屏蔽电缆电磁辐射的研究  

Suppressing radiated noise of unshielded cable on the relay protection test signal source research

作　　者：冯晓伟 王本涛 刘焕强 董金星 刘翔 Feng Xiaowei;Wang Bentao;Liu Huanqiang;Dong Jinxing;Liu Xiang(State Grid Inner Mongolia Eastern Power Co.,Ltd,Hohhot 010010;Shandong Shanda Power Technology Co.,Ltd,Ji’nan 250101)

机构地区：[1]国网内蒙古东部电力有限公司,呼和浩特010010 [2]山东山大电力技术股份有限公司,济南250101

出　　处：《电气技术》2020年第3期44-51,共8页Electrical Engineering

摘　　要：为满足继电保护测试信号源技术规范中的电磁辐射发射限值要求,针对目前继电保护测试信号源连接开关量、模拟量电缆辐射发射超标问题,提出了抑制非屏蔽电缆上共模电流方法以减小辐射发射噪声。基于电磁波与天线理论,建立了继电保护测试仪及非屏蔽电缆辐射发射的电路模型,分析了对辐射发射强度产生影响的主要电路参数,结果显示,在30~100MHz范围内,共模辐射发射噪声源强于差模辐射发射源。并根据共模辐射发射电路模型特性,给出抑制电缆共模电流的3种处理方法,即减小共模电流的大小,抑制电流谐波分量的频率,缩短电缆的长度。试验测试结果表明:抑制电缆共模电流方法能够减低辐射发射量22dB,具有电路处理简单、通用性强等特点。In order to meet the electromagnetic radiation emission limit requirements in the relay protection test signal source technical specification,the method of suppressing the common mode current on the unshielded cable is proposed for the current relay protection test signal source connection switch quantity and the analog cable radiation emission exceeding the standard problem.To reduce the radiated emission noise.Based on electromagnetic wave and antenna theory,a circuit model of relay protection tester and radiation transmission of unshielded cable is established.The main circuit parameters affecting the radiation emission intensity are analyzed.The results show that common mode radiation emission is in the range of 30~100MHz.The noise source is stronger than the differential mode radiation emission source and according to the characteristics of the common mode radiation emission circuit model,three processing methods for suppressing the common mode current of the cable are given,that is,the size of the common mode current is reduced and reduced.The frequency of the small current harmonic component reduces the length of the cable.The test results show that the method of suppressing the cable common mode current can reduce the radiation emission by 22dB,and has the characteristics of simple circuit processing and strong generality.

关 键 词：辐射发射 非屏蔽电缆 共模辐射 共模电流 仿真 

分 类 号：TM77[电气工程—电力系统及自动化]