Title :
Effects of Thermal Cycling and Thermal Stability on 2G HTS Pancake Coils
Author :
Nunez-Chico, Ana B. ; Martinez, E. ; Angurel, L.A. ; Navarro, Rafael
Author_Institution :
Dept. de Cienc. y Tecnol. de Mater. y Fluidos, Univ. de Zaragoza, Zaragoza, Spain
Abstract :
Degradation of superconducting critical currents of 2G-HTS coils may appear upon thermal cycling due to the tensile stress differences of its elements that induce increasing tape damages. We report on the thermal cycling and thermal stability effects of round epoxy-impregnated pancake coils under two cooling conditions (liquid nitrogen and conduction cooling). Thermal stability has been analyzed by measuring the quench development and propagation. Minimum quench energy values and longitudinal and radial propagation velocities are reported. The influence of different epoxy impregnations and number of turns in the thermal cycling effects and quench behavior has been studied.
Keywords :
critical currents; high-temperature superconductors; resins; superconducting coils; superconducting tapes; thermal stability; 2G HTS pancake coils; conduction cooling condition; liquid nitrogen cooling condition; longitudinal propagation velocity; quench energy; quench propagation; radial propagation velocity; round epoxy-impregnated pancake coils; superconducting critical currents; tape damages; tensile stress; thermal cycling; thermal stability; Coils; Current measurement; Integrated circuits; Temperature measurement; Thermal conductivity; Thermal stability; Voltage measurement; 2G-HTS conductors; Quench; Superconducting magnets; Thermal cycling; superconducting magnets; thermal cycling;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2014.2364680
