Study on method to suppress decay of trapped magnetic fluxes in the HTS bulk subjected to perturbation of external magnetic field by use of shielding coil wound of HTS wire
Study on method to suppress decay of trapped magnetic fluxes in the HTS bulk subjected to perturbation of external magnetic field by use of shielding coil wound of HTS wire
复制标题
高温超导导线绕制屏蔽线圈抑制受外磁场扰动的高温超导体中俘获磁通衰减方法的研究
DOI：
10.1109/tasc.2010.2093111
复制
发表时间：
2011
期刊：
影响因子：
--
通讯作者：
J. Ogawa and D. Miyagi
中科院分区：
文献类型：
--
作者：
K. Yamagishi;O. Tsukamoto;J. Ogawa and D. Miyagi
当高温超导块体受到外加磁场的扰动时，块体中的俘获磁通会衰减。在高温超导块体装置中，如高温超导马达和磁悬浮轴承，由于块体不可避免地受到外部磁场的扰动，块体中捕获的磁通有可能消失。为了使这些装置稳定可靠地工作，有必要研究抑制衰变的方法。我们以前的实验表明，这种衰变是由于块体中的交流损耗引起的块体温度升高所引起的。为了降低整体交流损耗，提出了一种在本体周围放置短路的高温超导屏蔽线圈绕组的方法。实验表明，采用铋银包绕屏蔽线圈，有效地抑制了俘获磁通的衰减。本文对GdBCO线材线圈绕组的屏蔽性能进行了实验研究，并与铋/银护套线材线圈绕组的屏蔽性能进行了对比。从屏蔽性能和降低交流损耗的角度出发，对屏蔽线圈的各种布置方式进行了交流损耗计算，找出了一种较佳的屏蔽线圈布置方式。
Trapped magnetic fluxes in HTS bulks are decayed when the bulks are subjected to perturbation of external magnetic fields. In HTS bulk apparatuses such as HTS bulk motors and magnetic levitation bearings, there is a possibility that the trapped magnetic fluxes in the bulks disappear because the bulks are inevitably subjected to perturbations of the external magnetic fields. For those apparatuses to work stably and reliably, it is necessary to develop methods to suppress the decay. It was shown in our previous experiments that the decay is caused by temperature rises of the bulks due to AC losses in the bulks. The authors proposed a method to put a shorted shielding coil wound of HTS wire around the bulk aiming at reduction of the AC losses in the bulk. It was experimentally shown by use of a shielding coil wound of Bi/Ag sheathed wire that the decay of the trapped magnetic flux was effectively suppressed. In this paper, shielding performance of the coil wound of GdBCO wire was experimentally investigated comparing with that of the coil wound of Bi/Ag sheathed wire. AC losses in the bulks and shielding coils are calculated for various arrangements of the shielding coil to find a preferable shielding coil arrangement from stand points of shielding performance and reduction of AC losses.