Luan Tian, Zhou Tianwei, Chen Xuzong, Ma Zhaoyuan
School of Electronics Engineering and Computer Science, Peking University, Beijing 100871, People's Republic of China.
Shanghai Institute of Optics and Fine Mechanics, Chinese Academy of Sciences, Shanghai 201800, People's Republic of China.
Rev Sci Instrum. 2014 Feb;85(2):024701. doi: 10.1063/1.4864051.
We present a modified Bitter-type electromagnet which features high magnetic field, fine electronic properties and efficient heat removal. The electromagnet is constructed from a stack of copper layers separated by mica layers that have the same shape. A distinctive design of cooling channels on the insulating layers and the parallel ducts between the layers ensures low resistance for cooling water to flow. A continuous current control system is also made to regulate the current through the electromagnet. In our experiment, versatile electromagnets are applied to generate magnetic field and gradient field. From our measurements, a peak magnetic field of 1000 G and a peak gradient field of 80 G/cm are generated in the center of the apparatuses which are 7 cm and 5 cm away from the edge of each electromagnet with a current of 230 A and 120 A, respectively. With the effective feedback design in the current control system and cooling water flow of 3.8 l/min, the stability of the current through the electromagnets can reach 10(-5).
我们展示了一种改进型的比特型电磁铁，其具有高磁场、良好的电子性能和高效的散热能力。该电磁铁由一叠由相同形状的云母层隔开的铜层构成。绝缘层上独特设计的冷却通道以及层间的平行管道确保了冷却水流动的低阻力。还制作了一个连续电流控制系统来调节通过电磁铁的电流。在我们的实验中，使用多功能电磁铁来产生磁场和梯度场。根据我们的测量，在距每个电磁铁边缘7厘米和5厘米处的装置中心，分别通入230安和120安电流时，可产生1000高斯的峰值磁场和80高斯/厘米的峰值梯度场。通过电流控制系统中的有效反馈设计以及3.8升/分钟的冷却水流速，通过电磁铁的电流稳定性可达到10的负5次方。
