Development of a persistent current switch for HTS magnets
Development of a persistent current switch for HTS magnets
复制标题
开发用于高温超导磁体的持续电流开关
DOI：
10.1109/tasc.2004.830534
复制
发表时间：
2004
影响因子：
1.8
通讯作者：
M. Terai
中科院分区：
文献类型：
--
作者：
T. Tosaka;T. Kuriyama;M. Yamaji;K. Kuwano;M. Igarashi;M. Terai
介绍了一种用于高温超导（HTS）磁体的持续电流开关（PCS）的设计思想、制作工艺和实验结果。近年来，用Ag包覆的Bi 2223合金丝制备了大尺寸的高温超导磁体。即使在高温超导磁体的情况下，持续电流模式也具有长时间保持稳定磁场的优点。高温超导磁体PCS是实现持续电流工作模式的关键部件。用于HTS磁体的PCS必须在与HTS线圈相同的操作温度下工作，并且PCS导体的电阻率应该足够大以减少充电期间的能量耗散并缩短切换时间。为了满足这些要求，PCS导体采用YBCO薄膜。PCS在真空中使用，当开关“打开”时，由低温冷却器在20 K左右进行传导冷却。为了将PCS从“开”改变为“关”，通过电加热器将PCS的温度升高到约100 K。介绍了一种用于高温超导磁体的PCS的新设计思想。给出了额定电流运行、开关运行和持续电流运行的试验结果。
This paper describes design concept, fabrication, and experimental results of a persistent-current switch (PCS) for high temperature superconducting (HTS) magnets. Recently large-size HTS magnets have been fabricated with Ag-sheathed Bi2223 wires. Even in the case of HTS magnets, persistent-current mode has the advantage of maintaining a steady magnetic field for long periods. A PCS for an HTS magnet is a key component to realize persistent-current mode. A PCS for an HTS magnet must work at the same operating temperature as an HTS coil, and electrical resistivity for a PCS conductor should be sufficiently large to reduce the energy dissipation during charge and to shorten the switching time. To satisfy these requirements, a YBCO thin film is adopted for a PCS conductor. The PCS is used in a vacuum and conductively cooled by a cryocooler at around 20 K when the switch is "on". To change the PCS from "on" to "off", the temperature of the PCS is increased to around 100 K by electrical heaters. A new design concept of a PCS for an HTS magnet is introduced. And the test results of rated current operation, switching operation and persistent-current operation are shown.