Quench-protected, refrigerated superconducting magnet

摘要

A superconducting magnet including a superconducting coil assembly having a magnet cartridge, a cryocooler coldhead having a cold stage in thermal contact with the magnet cartridge, and a thermal buffer assembly. The thermal buffer assembly includes an inlet tube and an outlet tube each having an end connected to a helium pressure container which is placed in thermal contact with the magnet cartridge. A first gas pressure regulator on the inlet tube supplies helium gas and a second gas pressure regulator on the outlet tube vents helium gas so as to maintain a generally constant pressure for the helium gas within the helium pressure container. The high specific heat per unit volume of the pressurized gaseous helium acts as a thermal buffer to extend the time the magnet can operate superconductively without the cryocooler before quenching, such as during an electric power outage.