Magnetisation losses of Roebel cable samples with striated REBCO strands were measured at different temperatures between 4K and 85K in ac magnetic fields up to 0.2T. While the losses of Roebel cables with non-striated strands were shown previously in quantitative agreement with the losses of magnetically coupled two side-by-side tape stacks as thin Norris' strips, significantly differences in...
Narrowed high-temperature superconducting (HTS) tapes have much smaller hysteresis loss and eddy current loss per unit tape width according to analytical and experimental data. Multi-filamentary technology is widely recognized as an effectively way of reducing the AC loss of HTS tapes by cutting each tape into multiple narrower filaments while maintaining the whole structure. But the magnetic...
The Spiral Copper-plated Striated Coated-conductor cable (SCSC cable) is our novel concept of high current cable with low ac loss, in which copper-plated multifilament (striated) coated conductors are wound spirally on a metal core in multiple layers. Whereas copper-plating allows current sharing among filaments against local defects in a filament, filaments are decoupled electromagnetically...
CORC, STAR, and in general, conductors consisting of a set of helically wound conductors on a round core are of substantial interest for use in High Energy Physics accelerator magnets because of their high Bc2 and excellent transport properties in high fields. Their magnetization properties as well as their AC loss are also of interest, because they can cause particle beam defocusing and...
This study investigates the magnetization of ReBCO cables, utilizing experimental measurements in magnetic fields up to 30 T at 4.2 K. The cable is comprised of 29 ReBCO tapes, with a cable OD of 3.63 mm and cable pitch of 7.16 mm. The tapes were 2 mm wide and had a substrate thickness of 30 ฮผm, and a Cu plating thickness of 5 ฮผm. The cable had an Ic of 1675 A at 77 K and self-field. The ReBCO...
This presentation reports AC loss study for parallel-wound HTS coils used for AC applications, e.g. fusion PF coil and rotational machines. The reason for parallel winding is to increase the current rating of winding without increasing too much the winding inductance. We made several four-conductor parallelly wound HTS coils and measured both the current distribution and AC loss. Our...
High-current HTS cables made of stacked REBCO tapes are being considered for large superconducting magnet systems for fusion and other applications. AC losses are critical when analyzing a stack of non-insulated tapes. Using finite element software such as COMSOL, it is possible to model a 3D stack of non-insulated REBCO tapes and assess how AC losses vary, depending on factors such as the...
Reducing AC loss in high-temperature superconducting (HTS) coils is critical in HTS applications such as SMES (superconducting magnetic energy storage) and fast ramping magnets. One effective approach is applying magnetic flux diverters to reshape the magnetic field distribution in the vicinity of end coils/windings. However, the benefits of MFDs diminish in high magnetic fields that exceed...
