基于闭合超导线圈组的磁场屏蔽系统研究

项目名称： 基于闭合超导线圈组的磁场屏蔽系统研究

项目编号： No.51477088

项目类型： 面上项目

立项/批准年度： 2015

项目学科： 电工技术

项目作者： 顾晨

作者单位： 清华大学

项目金额： 89万元

中文摘要： 磁场屏蔽是许多精密测量科学的通用保障性技术。为了丰富磁屏蔽家族的成员，弥补传统屏蔽系统的局限性，项目提出了一种基于闭合超导线圈组的磁场屏蔽系统。它通过主动调控线圈之间的半径比和匝数比，可实现任意比例感应抵消外界噪音磁场。这种屏蔽系统具有以下优点：第一，光学透明，被保护物体可与外界进行光学和无线通讯。第二，自动抵消磁场，无需辅助电子设备；第三，低频区屏蔽能力不衰减，经初步测试，在0.1-200Hz范围，即因输电线和用电器产生噪音磁场的主要频域，系统屏蔽能力一致。 本项目拟对该新型屏蔽系统设计理论、电磁特性和工程实现方法开展研究，具体研究内容和目标包括：第一，建立屏蔽系统电磁场逆问题及鲁棒性设计理论；第二，研究屏蔽系统频谱，幅域特性，并从高温超导磁通穿透的微观过程阐述机理；第三，探索屏蔽系统的工艺实现方法，搭建一套配合心磁测量的屏蔽系统，可屏蔽噪音磁场40dB以上，在三甲医院环境开展人体测试。

中文关键词： 屏蔽效能；电磁干扰；电磁环境；电磁防护

英文摘要： Magnetic shielding provides general protection for precision measuring apparatus. To enrich the family member of magnetic shielding, we propose a novel magnetic shielding system based on closed high temperature superconductor(HTS) coils. The capability of the system is based on the principle that a closed loop can resist flux variation and keep the flux constant inside. More important thing is that the ratio of the radius and the turn number between the coils have to satisfy a number of conditions, with which arbitary cancellation ratio can be reached. The advantage of the system is that first, it is open-type with which the protected target can communicate with outsides optically or wirelessly; secondly, it automatically resists magnetic field without using any electronic devices and thus has good property in mobility and compatibility; third, the system has a broad frequency spectrum, in particularly at low frequency. The initial testing shows that the shielding ability of the system at 0.1-200 Hz, the spectrum caused by 50Hz power line or electrical devices does not show evident decay at this spectrum. In this project, we are going to study the design theory of the system, eletromagnetic characteristic of the system and construction technique of the system in a parallel way. More specifically first, build the inverse magnetic field theory and robust design theory for the shielding system; second, study the frequency spectrum of system and explain the property based on flux motion theory of the HTS； third, study the construction technique of the system and build a shielding system for Magnetocardiography (MCG) measurement, which will be used in a hospital for human being testing. The system can resist magnetic noises in a scale of 40dB.

英文关键词： Shielding ability;Electromagnetic interference;Electromagnetic enviorment;Electromagnetic protection