Speaker
Description
The discovery of high-temperature superconductors in 1986 seemed to herald the end of the era of large cryogenic systems. Phase transition temperatures of up to 138 K were achieved in ceramic materials within a short period of time. Superconductivity at room temperature seemed within reach. However, further success proved much more difficult than expected. The material class of hydrides, for example, requires pressures far too high (> 100 GPa) for any practical application, and the brittleness of ceramic superconductors initially posed major challenges for cable manufacturers. For many years, HTS conductors existed as niche demonstration projects, initially in areas such as current limiters, generators, and motors. In 2014, a 1-kilometer-long HTS cable was integrated into the power grid of the city of Essen, Germany, on a trial basis for the first and for a limited time.
The complex process of manufacturing HTS cables has now been mastered, resulting in a dramatic fall in production costs. At the same time, the quest for higher magnetic fields pushed conventional superconducting technology towards its limits, creating new opportunities. Among other achievements, this led to the development of HTS magnets cooled with liquid helium — well below their phase transition temperature. Stable magnetic fields of up to 45 tesla can now be generated with very compact magnets. This has led to significant progress in areas such as fusion technology, which was once considered highly futuristic.
The increasing technical maturity of HTS technology does not render cryogenics obsolete; rather, it creates new opportunities and demands for cryogenic systems. This presentation will discuss the cryogenic challenges, cooling concepts, and practical implementation of modern HTS applications. Examples from the fields of power transmission, fusion technology, particle accelerators, and other industrial systems illustrate how advances in superconductivity are driving renewed demand for innovative cryogenic solutions.