HTS magnet protection: quench detection and protection techniques designed for HTS magnets

Yasuyuki Miyoshi

ICYS-Sengen researcher

Applications of superconductors, as far as the industrial scale conductors are concerned, are mostly in winding a magnet. High temperature superconductors (HTS), compared to the conventional low temperature superconductors (LTS), have several advantages such as low cryogenic cost, high current and high field capacities. Recently, the industrial scale HTS technology has advanced to produce long length and high strength conductors, which have propelled efforts on the realisation of HTS magnets. For example, HTS magnets are being developed for energy storage (SMES), low cryogenic cost MRI magnets, high field insert coils for research (NMR or high field facilities), and accelerator magnets (CERN). In all superconducting magnets, quench protection is a critical part.

Quench is a rapid and non-recoverable transition from the superconducting state to the normal state, and protecting a superconducting magnet makes sure such an event does not remain a local phenomenon that leads to damages to the magnet. The proposed research at ICYS is the development of techniques highly relevant to the HTS magnet technology: quench detection and protection.

In this talk, a brief overview of the fundamentals of quench protection will be given and technical challenges owing to properties of HTS will be discussed.