地电流检测用磁场测量仪的干扰分析与抑制  

Interference Analysis and Its Rejection of Magnetic-Field Measurement Apparatus for Ground Current Testing

作　　者：张向明[1] 赵治华[1] 潘启军[1] 

机构地区：[1]海军工程大学舰船综合电力国防科技重点实验室海军工程大学电力电子技术研究所,武汉430033

出　　处：《电工技术学报》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)

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.

关 键 词：磁场测量仪 电磁干扰 电容性耦合 电场屏蔽 

分 类 号：TM93[电气工程—电力电子与电力传动]