| 摘要 |
PURPOSE:To securely protect a superconductive magnet from normal conduction transition in avoidance of provision of excessive electric resistance by a method wherein a superconductive magnet is segmented to plural sub-coils, respecive sub-coils are connected to No.2 protective resistance, and a protection switch is controlled by No.1 and No.2 protective resistances. CONSTITUTION:A superconductive magnet is halved inside in ultralow temperature vacuum adiabatic vessel 2 to form sub-coils 11 and 12. Subcoil 11 is connected with subcoil 12 in series via No.2 protective resistance 41 which is connected in parallel with No.2 protective switch 51. Further, the far ends of subcoils 11 and 12 are connected across No.1 protective resistance 42, and a DC current is supplied from a DC source 3 for excitation to subcoils 11 and 12 via No.1 protective switch 52. When subcoils 11 and 12 are returned to normal conduction, the switches 52 and 51 are opened to drain a DC current in magnet into a protective circuit. Thus, the energy stored in the magnet is consumed in protective resistances 41 and 42, so that the machine is securely protected from a normal conduction transition. |
