| 摘要 |
PURPOSE:To obtain a coil which can obtain excellent stability of a magnetic field at a low cost by forming a permanent-current closed loop for every unit coil of a hybrid coil comprising two or more superconductor unit coils. CONSTITUTION:In a hybrid superconductor coil 10 comprising two or more unit coils 11 and 12, a permanent-current closed loop is formed for every coil of the unit coils 11 and 12. For example, the hybrid coil 10 is formed by arranging the superconductor coil 11 for a high magnetic field on the inner side and arranging the superconductor coil 12 for a low magnetic field in a coaxial pattern. A power source 15 and a permanent current switch 13 are connected to the superconductor coil 11 for the high magnetic field. A power source 16 and a permanent current switch 14 are connected to the superconductor coil 12 for the low magnetic field. An Nb3Sn wire is used for the superconductor coil 11 for the high magnetic field. An Nb-Ti alloy wire is used for the superconductor coil 12 for the low magnetic field. Because there is no part using normal conductivity connection between the unit coils in this way, the attenuation of permanent current caused by the resistance at the node is eliminated, and the high stability in the magnetic field is obtained. |
