サーモサイフォン循環液体水素冷却によるSMES モデル装置

抄録

A model of superconducting magnet energy storage device has been fabricated to demonstrate its cooling scheme by using liquid hydrogen flow through thermosiphon loops. A stack of three double pancake coils wound with MgB₂ Rutherford cables are in thermal contact with thermosiphon pipes through pure copper plates which cover the each pancake coil surface. To prevent eddy current from being induced in the copper plates, the latter are slit into strips. After completion of the model device, performance test was carried out by actually supplying liquid hydrogen. The coil has been kept at a temperature lower than 21 K and has been charged up to a nominal current of 600 A. On the other hand, a large amount of evaporation of liquid hydrogen due to oscillation of some sort and gradual temperature rise at the coil terminals resulting in quench were observed, and these issues should be resolved in the future.