Degradation of critical current in an HTS coated conductor considering curvature of ellipse for rotating flux pump. (January 2018)

• Record Type: Journal Article
• Authors: Han, Seunghak; Lee, Jeyull; Jeon, Haeryong; Ko, Tae Kuk; Kim, Ho Min; Kim, Ji Hyung; Hyeon, Chang Ju; Yoon, Yong Soo
• Is Part Of: Cryogenics. Volume 89(2018)
• Page Start: 141
• Page End: 146
• Publication Date: 2018-01
• Subjects: Critical current -- Rotating flux pump -- Elliptical winding -- HTS coated conductor; Low temperature engineering -- Periodicals; Low temperature research -- Periodicals; 536.56
• DOI: 10.1016/j.cryogenics.2017.12.003
• Languages: English
• ISSNs: 0011-2275

Abstract

Highlights: Critical current in HTS CC is degraded by bending strain. Bending strain varies depending on the winding shape even at the same winding diameter. I c degradation in HTS CC depends on winding direction and presence or absence of mandrel. Experimental results and theoretical predictions were compared by Ekin's exponential formula and Weibull's distribution function. Abstract: A rotating HTS flux pump is used to study the charging characteristics of superconducting synchronous motor. In order to design the rotating flux pump, the elliptical winding is essential. Numerous studies have been conducted on the degradation of the critical current with respect to the bending condition of the second generation (2G) high-temperature superconducting (HTS) tape. These studies focused on the same radius of curvature depending on the bending position. Therefore, in this paper, the critical current in a HTS coated conductor (CC) considering the curvature of elliptical shape is measured with regard to nine mandrels. These are a tall prolate ellipsoid, oblate ellipsoid and semicircle. In the tall prolate ellipsoid, the degradation of the critical current was the least. The diameters of each shape are 20, 30 and 40 mm, respectively. Finally, the experimental observations have been compared with the theoretical predictions.