Protection circuits for superconducting magnets

As the technology of controlled nuclear fusion progresses, plans for new experimental reactors include much longer duty cycles than those of earlier experiments. Many of the magnet systems for these reactors must be superconducting due to the prolonged or continuous high current levels required. The large initial investment of a superconducting magnet system justifies a protective dump circuit. This circuit must operate if the magnet goes normal or in the event of failure of some of the critical auxiliary equipment. This paper examines two applications of superconducting magnet protection for fusion experiments. A novel dc interrupter being developed especially for this purpose is also discussed