摘要
在较高频率条件下,地电流检测用磁场测量仪因受外界电磁场干扰导致了测量的不准确。在分析电容性耦合干扰和电感性耦合干扰特点的基础上,设计了判断磁场测量仪干扰耦合途径的实验方法,并根据所设计实验判断出较高频率条件下磁场测量仪所受干扰主要为电容性耦合干扰。最后通过改进电路设计和采取电场屏蔽措施,使干扰输出降低30dB,显著提高了磁场测量仪的有效测量范围。
The magnetic-field measurement apparatus, which is designed for ground current testing, can be easily interfered by exoteric electromagnetic field at high frequencies. The characteristics of capacitive coupling interference and inductive coupling interference are analyzed and the means of judging coupling mode of EMI is presented in this paper. Then, the conclusion that the EMI noise output of the measurement apparatus mainly comes from capacitive coupling is obtained through a series of experiment. Finally, the EMI noise output of the measurement apparatus is reduced by 30dB and the measurement scope of the new apparatus is expanded greatly, by improving the design of electric circuit and adopting electromagnetic shield.
出处
《电工技术学报》
EI
CSCD
北大核心
2007年第7期113-118,共6页
Transactions of China Electrotechnical Society
基金
国家自然科学基金资助项目(50421703
50677070)
关键词
磁场测量仪
电磁干扰
电容性耦合
电场屏蔽
Magnetic-field measurement apparatus, EMI, capacitive coupling, electromagnetic shield
作者简介
张向明,男，1983年生，博士研究生，研究方向为电力系统中的电磁兼容。
赵治华,男，1962年生，教授，博士生导师，从事电磁场计算及电磁兼容性等方面的研究。
