The large scale use of superconductivity continues to be dominated by applications for which there is generally no conventional option. In these cases, superconductivity has enabled new science and technology that could not exist without it. Thanks to persistent ongoing research, new ancillary technology and the development of new materials, the field is far from exhausted. The fields of fusion energy and high energy physics (HEP) have particularly benefited from the application of superconductivity. High magnetic fields are absolutely necessary to achieve the required performance parameters. Even though superconductivity is an enabling technology for these fields, it comes with a number of challenges. The progress in development of applications is driven from one side by the available materials and on the other, by the evolution, or sometimes revolution, in ancillary technologies. Technology for use in both fusion and accelerator magnets begins with the same materials and inherent constraints, yet results in substantially different configurations and unique challenges due to the operational requirements for the respective applications. This paper presents a comparison of the technology developed by the fusion and high energy physics programs, both the similarities and the differences, and prospects for future development.
When the quenching occurs in a superconducting coil, excessive jule heating in normal area may damage the coil. It is necessary to detect quenching in the coil as soon as possible and discharge the magnetic energy stored in the coil. Therefore, we propose a superconducting coil protection system based on an active power method. The system is highly resistant to the noise and does not require cancel voltage taps, so it is useful for both AC and DC coils. We have presented the effectiveness of the system using some test coils cooled in LN2 or LHe. However, we have not discussed the effectiveness of the proposed system for helium-free cryocooled magnets, in which a larger temperature rise occurs after quenching than in liquid-cooled magnets. In this paper, we verify the effectiveness and practicality of the proposed system through coil protection tests for a cryocooled Nb3Al LTS coil.