Cooling and operating stationary & rotating superconducting arrangements: concepts of the past, special requirements, and recent developments

Historically and even today for selected applications, superconducting coils have been cooled by liquid helium pool cooling.
The technical viability and business case in magnets and power applications has been widely influenced by
a) the operating conditions and b) the available cooling devices.
HTS have simplified cryogenic measures and considerably extended the devices' suitable power range.
For stationary and rotating applications, specific requirements pose additional challenges for cooling concepts.
However, current trends in magnets and rotating machines may enable new concepts.
This presentation will give an overview of the historical basis, special aspects, the changes, and new prospects.