A study on the effect of the condition number in the magnetic field mapping of the Air-Core solenoid
A study on the effect of the condition number in the magnetic field mapping of the Air-Core solenoid
复制标题
空心螺线管磁场映射中条件数影响的研究
DOI：
10.9714/psac.2015.17.2.031
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发表时间：
2015
影响因子：
0.3
通讯作者：
Sangjin Lee
中科院分区：
文献类型：
--
作者：
Li Huang;Sangjin Lee
[映射是磁场分析和设计中的有用工具。在某些特定的研究领域，如核磁共振（NMR）或磁共振成像（MRI）等，高精度地绘制感兴趣空间的磁场分布是非常重要的。本文从求解拉普拉斯场方程出发，提出了一种空心螺线管中心体积的间接映射方法。通过对测绘计算的数学分析可知，由测量点生成的矩阵的条件数对测绘结果的误差有很大的影响。本文介绍了野外测绘中测点的两种不同布置方法：螺旋柱面线法和平行柱面线法。根据条件数，推荐使用HCL方法用一个探头测量场分量。作为一个简单的例子，我们映射了MRI主磁体系统中的磁场。通过对不同方法计算结果的比较，说明在野外成图计算中应用条件数来减小误差是可行的，也是方便的。最后，给出了空心螺线管中心体积磁场分布的一些指导原则。
【Mapping is a useful tool in the magnetic field analysis and design. In some specific research area, such as the nuclear magnetic resonance (NMR) or the magnetic resonance imaging (MRI), it is important to map the magnetic field in the interesting space with high accuracy. In this paper, an indirect mapping method in the center volume of an air-core solenoid is presented, based on the solution of the Laplace's equation for the field. Through the mathematical analysis on the mapping calculation, we know that the condition number of the matrix, generated by the measurement points, can greatly affect the error of mapping result. Two different arrangement methods of the measurement points in field mapping are described in this paper: helical cylindrical line (HCL) method and parallel cylindrical line (PCL) method. According to the condition number, the HCL method is recommended to measure the field components using one probe. As a simple example, we mapped the magnetic fields in a MRI main magnet system. Comparing the results in the different methods, it is feasible and convenient to apply the condition number to reduce the error in the field mapping calculation. Finally, some guidelines were presented for the magnetic field mapping in the center volume of the air-core solenoid.】