Effect of combining a DC bias current with an AC transport current on AC losses in a high temperature superconductor

被引:2
作者
Dolez, P [1 ]
des Ligneris, B
Aubin, M
Zhu, W
Cave, J
机构
[1] Univ Sherbrooke, Dept Phys, Sherbrooke, PQ J1K 2R1, Canada
[2] Univ Sherbrooke, Ctr Rech Phys Solide, Sherbrooke, PQ J1K 2R1, Canada
[3] VPTI Hydro Quebec, Technol Emergentes Prod & Stockage, Varennes, PQ, Canada
基金
加拿大自然科学与工程研究理事会;
关键词
D O I
10.1109/77.783481
中图分类号
TM [电工技术]; TN [电子技术、通信技术];
学科分类号
0808 ; 0809 ;
摘要
Creating complex flux configurations by superposing a de current or magnetic field onto the ac current in a type II superconducting tape should lead to a variety of peculiar behaviors. An example is the appearance of the Clem valley, a minimum in the ac losses as a function of the de bias amplitude, which has been theoretically studied by LeBlanc et al,, in the continuation of Clem's calculations. These situations have been investigated by applying a de current to a silver-gold sheathed Bi-2223 tape at 77 K (critical current 29 A), in addition to the usual ac transport current. The ac losses were measured by the null calorimetric method to ensure that the total losses were being accounted for. These were recorded for different values of the ac and de currents, leading to the observation of two different behaviors depending on the ac current. Our revelation of the Clem valley is, to our knowledge, the first experimental validation of this phenomenon in high temperature superconductors, and may provide a simple way of reducing the ac loss in industrial applications of these materials.
引用
收藏
页码:1065 / 1068
页数:4
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