Filamentary YBCO conductors for AC applications

Hysteretic loss reduction in striated YBCO

“…However, the architecture presently being developed for high temperature superconducting (HTS) coated conductors is primarily for dc environments [3][4][5][6]. The YBCO films used in coated conductors are characterized by high aspect ratios, with widths up to a centimeter compared to thicknesses in the range of 0.3 to several lm.…”

“…To minimize these losses, Carr and Oberly suggested a design for a low ac loss coated conductor [4]. This design calls for the coated conductor to be subdivided into thin linear filaments, or striations, and then for the tape as a whole to be twisted.…”

The Integration of YBACU3O6+X Coated Conductors into Magnets and Rotating Machinery

“…The main route to hysteresis (and overall) loss reduction that has been explored in recent years is the replacement of the uniform wide YBCO film with a set of parallel narrow filaments (stripes) [2][3][4][5][6][7][8]. The first experiments have demonstrated that the hysteresis loss in experimental multifilamentary samples can be reduced by at least an order of magnitude.…”

“…Usually in the literature [1,2,11] one can find a description of the axial twist shown in Fig. 2(a).…”

Thin YBa2Cu3O7-δpatterns by Chemical Solution Processing using Ink-Jet Printing

“…There will always be eddy current losses associated with substrate and stabilization layers, which can be reduced by maximizing the substrate resistance and by also striating the stabilization layer. These methods, and avoiding interfilamentary bridging, also reduce coupling currents; but twisting the conductor, or ideally fully transposing the filaments, is required to minimize coupling losses [10][11][12][13][14][15][16][17][18]. This filamentary superconducting structure can be accomplished through several techniques which can be divided into two main approaches: with or without material removal.…”