Superconducting magnet device and method for limiting current decrease in case of abnormality therein

Abstract

A superconducting magnet device including a superconducting coil formed of a high-temperature superconducting wire, a power supply which supplies current to the superconducting coil, and a protector capable of forming a short-circuit path which short-circuits both ends of the superconducting coil to each other is installed. Current is made to flow from the power supply to the superconducting coil in a superconducting state, and the superconducting coil thereby generates a magnetic field. After the magnetic field is generated, when an abnormality of the superconducting magnet device is detected, or when the power supply and the superconducting coil are disconnected from each other, the short-circuit path is formed by the protector.