AC loss properties of YBCO superconducting tapes fabricated by IBAD–PLD technique

Total AC Loss Characteristics in a Stacked YBCO Conductor

“…However, the values of the YBCO stack are significantly lower than the values of the single conductor in low and intermediate magnetic field regions, though the values of both the YBCO stack and the single conductor approximately agree with each other in high magnetic field region. The above results are consistent with Iwakuma et al's report [5]. As Iwakuma et al pointed out, the above results are attributed to demagnetization effect.…”

“…Analytically and numerically obtained AC losses in assembled YBCO conductors were reported by a couple of authors [1]- [4]. Measurements of magnetization losses without transport current in stacked YBCO conductors (YBCO stacks) which were assembled face to face were reported by Iwakuma et al [5]. However, measurements of total AC losses in such a YBCO stack carrying AC transport current in an AC transverse magnetic field were not reported.…”

AC loss evaluation of an HTS insert for high field magnet cooled by cryocoolers

“…In order to estimate the parallel-field loss Q // in the k-th turn, the SC layer of coated conductor could be considered as an infinite slab with the thickness d of SC layer because d is much smaller than the tape width 2a. On the other hand, the magnetic interactions between turns [10][11][12][13][14] have to be taken into account for estimation of the perpendicular-field loss Q \ . It has been well known that there are three theoretical expressions to estimate AC losses in SC strips exposed to a cyclic external magnetic field perpendicular to the broad faces [18][19][20][21][22][23].…”

“…The proposed expression to estimate the AC losses in the HTS inserts for 32-T magnet is also applicable for the case where the radial component of a local magnetic field applied to every part of the windings in solenoid coils is larger than the full penetration field, but such a situation could not be realized for an HTS insert constituting a high field magnet with relatively tall height. If the local magnetic field becomes less than the full penetration field, it has been well known that the magnetic interactions between SC wires strongly affect the AC loss properties, for example, in NbTi multifilamentary wires [7][8][9], BSCCO tapes [10,11] and coated conductors [12][13][14]. In this paper, AC losses in an HTS insert coil designed for one of high field magnets [15] are numerically evaluated.…”

Acceptable coupling losses in coated conductors at industrial frequencies without twisting the superconducting stripes

“…However, any type of connection between the stripes increases the coupling losses between them. [15][16][17][18][19][20][21][22][23] The suggested full coating of the tape with normal metal 24,25 results in dramatic increase of the CLs. Therefore, twisting the stripes-like in superconducting cables-seemed to be inevitable.…”