Higherature superconducting (HTS) flux pumps are used to charge HTS coils at cryogenic temperatures without thermal and mechanical contact with the power supply at room temperature. We found that the larger the alternating magnetic field (AMF) penetrating into the HTS wire, the faster is the current charge rate in the HTS coil and the larger will be the amount of charge. AMF causes vortex pinning of the HTS wire to move, resulting in dynamic resistance (Rdyn) and electromotive force (EMF). Charging characteristics are determined by Rdyn and EMF which are generated by effective internal resistance (Reff) and open-circuit voltage (OCV), respectively. Even if AMF of the same magnitude penetrates the wires, the size of Reff and EMF generated will vary depending on the characteristics of the HTS wires. Therefore, in this study, Reff and OCV of a HTS wire are measured and compared with the results of HTS coil charging using a flux pump.
Bibliographical noteFunding Information:
Manuscript received October 29, 2018; accepted February 17, 2019. Date of publication February 27, 2019; date of current version March 29, 2019. This work was supported in part by the National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIP), and in part by “Human Resources Program in Energy Technology” of the Korea Institute of Energy Technology Evaluation, and Planning (KETEP), granted financial resource from the Ministry of Trade, Industry & Energy, Republic of Korea (Nos. 2016R1A2B4007324 and 20184030202270). (Corresponding author: Yong Soo Yoon.) S. Han, J. Lee, H. Jeon, and T. K. Ko are with the School of Electrical and Electronic Engineering, Yonsei University, Seoul 30722, South Korea.
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering