Title :
Theoretical and Experimental Magnetization Loss Comparison Between IBAD Coils and RABiTS Coils
Author :
Yiran Chen ; Min Zhang ; Chudy, Michal ; Wei Wang ; Zhaoyang Zhong ; Zhen Huang ; Coombs, T.
Author_Institution :
Eng. Dept., Cambridge Univ., Cambridge, UK
Abstract :
This paper presents a comparative study of ac magnetization losses in two types of 2 G HTS racetrack coils. The magnetic substrate made by RABiTS is the main difference between the two types, because ferromagnetic loss caused by magnetic substrate is accounted into the total ac losses. IBAD and RABiTS tapes were successfully wound into racetrack shape with identical geometry. The measurements were carried out by using electromagnetic method with pick-up coils under a sinusoidally varying external magnetic field, with amplitudes up to 27 mT, ranging from 10 Hz to 100 Hz at a temperature of 77 K. The field was oriented perpendicularly to the surface of the tapes. Experimental measurements were validated by applying theoretical models and the results showed that the magnetization loss in the MAG RABiTS coil is always higher than that in the NON MAG coil due to the presence of the magnetic substrate, which increases the magnetic field penetration into the coil and causes higher magnetic flux density within the penetrated region.
Keywords :
barium compounds; eddy current losses; high-temperature superconductors; magnetic flux; magnetic leakage; magnetisation; superconducting coils; superconducting tapes; yttrium compounds; 2G HTS racetrack coils; IBAD coils; IBAD tape; MAG RABiTS coil; NON MAG coil; RABiTS tape; YBCO; ac magnetization losses; electromagnetic method; external magnetic field; ferromagnetic loss; frequency 10 Hz to 100 Hz; magnetic field penetration; magnetic flux density; magnetic substrate; penetrated region; pick-up coils; racetrack shape; tape surface; temperature 77 K; total ac losses; Coils; Magnetic field measurement; Magnetic fields; Magnetic losses; Magnetization; Substrates; Superconducting magnets; AC magnetization loss; YBCO racetrack coil;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2012.2236592