Electro-thermal quench in metal-insulated nested REBCO coils for magnets over 40 T

TL;DR

This paper analyzes electro-thermal quench phenomena in high-field superconducting magnets with nested REBCO coils, identifying weak spots and proposing solutions to improve thermal stability for magnets over 40 T.

Contribution

It provides a detailed multiphysics quench analysis of nested REBCO and LTS magnet configurations, highlighting weak spots and suggesting mitigation strategies.

Findings

Identified critical weak spots prone to thermal quench.

Analyzed screening current effects on quench behavior.

Proposed methods to enhance thermal stability.

Abstract

Superconducting high field magnets have the capability to generate over 40 T, with multiple existing practical applications globally. However, at such high magnetic fields, these magnets are prone to rapid electrothermal quench which can affect the continuous operation of such magnets. A nested stack configuration, with multiple HTS inserts inside a LTS outsert, can be used for better thermal stability and compact design. We have performed detailed multiphysics quench analysis of such a nested stack high field magnet design under SuperEMFL project using our in-house software, which considers screening currents. Through various case studies, we have identified various weak spots in such a magnet, where thermal quench can be the most detrimental for magnet operation, and various ways are suggested to overcome this important issue.