Future cryogenic switchgear technologies for superconducting power systems

This paper introduces cryogenic switchgear that is needed for protection and control purposes in future multi-terminal superconducting power systems. Implementation of cryogenic switchgear is expected to improve system reliability and minimize overall volume and weight, but such switchgear is not available yet. Design of cryogenic switchgear begins by referring to conventional circuit breakers, a brief review of state-of-the-art switchgear technologies is presented. Then, promising cryogenic interruption media are identified and analysed with respect to physical and dielectric properties. Finally, we propose several cryogenic circuit breaker designs for potential aerospace, marine and terrestrial applications. Actuation mechanism for cryogenic switchgear is also investigated.