A sub-cooled liquid nitrogen (LN2) cooling system is known as an appropriate method for developing a high voltage superconducting fault current limiter (SFCL). The pressure of a sub-cooled LN2 cooling system should be controlled by injecting non-condensable gas such as gaseous helium (GHe) and gaseous neon (GNe) into the cryostat. Therefore, the electrical breakdown voltage of current leads is directly influenced by an injected gaseous medium. In this study, electrical insulation experiments on GHe and GNe are conducted and the results are compared with each other. Also, the dielectric characteristics of GHe and GNe are analyzed by using field utilization factors. It is found that the dielectric characteristics of GHe are superior to those of GNe under the same conditions. The experimental results are applicable for designing the current leads of a high voltage superconducting fault current limiter.
Bibliographical noteFunding Information:
Manuscript received August 03, 2010; accepted December 23, 2010. Date of publication February 10, 2011; date of current version May 27, 2011. This work was supported by Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (2010-0003558). H. Kang is with the Department of Electrical Engineering, Chungju National University, Chungju, Korea (e-mail: firstname.lastname@example.org). T. K. Ko is with the Electrical Engineering, Yonsei University, Seoul 120-749, Korea. Color versions of one or more of the figures in this paper are available online at http://ieeexplore.ieee.org. Digital Object Identifier 10.1109/TASC.2010.2103548
All Science Journal Classification (ASJC) codes
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Electrical and Electronic Engineering