- Volume 13 Issue 3
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Improvement of Degradation Characteristics in a Large, Racetrack-shaped 2G HTS Coil for MW-class Rotating Machines
- Park, Heui Joo ;
- Kim, Yeong-chun ;
- Moon, Heejong ;
- Park, Minwon ;
- Yu, Inkeun
- Received : 2017.10.19
- Accepted : 2017.12.12
- Published : 2018.05.01
Degradation due to delamination occurs frequently in the high temperature superconductors (HTS) coil of rotating machines made with 2nd generation (2G) HTS wire, and the authors have observed other similar cases. Since an HTS field coil for a rotating machine is required to have stable current control and maintain a steady state, co-winding techniques for insulation material and epoxy resin for shape retention and heat transfer improvement are applied during coil fabrication. However, the most important limiting factor of this technique is delamination, which is known to be caused by the difference in thermal expansion between the epoxy resin and 2G HTS wire. Therefore, in this study, the experimental results of mixing the ratio of epoxy resin and alumina (
2G HTS coil;Degradation;Delamination;Insulation material;Epoxy resin;Filler;Coefficient of thermal expansion
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