TY - JOUR
T1 - Experimental study on the lightning impulse dielectric strength of liquid nitrogen insulation medium according to various pressures
AU - Na, J. B.
AU - Kang, H.
AU - Chang, K. S.
AU - Kim, Y. J.
AU - Chu, S. Y.
AU - Kim, T. J.
AU - Kim, K. J.
AU - Lee, H. G.
AU - Ko, T. K.
N1 - Funding Information:
This research was supported by National R&D Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (No. 2009-0082742).
Copyright:
Copyright 2011 Elsevier B.V., All rights reserved.
PY - 2011/11
Y1 - 2011/11
N2 - The lightning impulse breakdown characteristics of liquid nitrogen are necessarily considered for designing high voltage superconducting machines required high reliability. This paper investigates the dielectric capability of liquid nitrogen (LN2) to withstand lightning impulse. To gain the dielectric capability of LN2 cryogenic cooling system, lightning impulse was induced in sphere-plane electrode systems which have six different diameters of sphere electrode. The pressure is one of major condition to decide dielectric strength at LN2 cryogenic cooling system. Thus, the gaseous nitrogen was injected to control pressure in the cryostat, ranging from 100 kPa to 200 kPa. Moreover, field utilization factor was calculated between sphere and plane electrode systems by a finite element method analysis. The electric field criterion of LN2 as insulation media was calculated from correlation between the experimental results and the field utilization factor. In the future, these results can be applied as the design parameter of electrical insulation for developing high voltage superconducting machines.
AB - The lightning impulse breakdown characteristics of liquid nitrogen are necessarily considered for designing high voltage superconducting machines required high reliability. This paper investigates the dielectric capability of liquid nitrogen (LN2) to withstand lightning impulse. To gain the dielectric capability of LN2 cryogenic cooling system, lightning impulse was induced in sphere-plane electrode systems which have six different diameters of sphere electrode. The pressure is one of major condition to decide dielectric strength at LN2 cryogenic cooling system. Thus, the gaseous nitrogen was injected to control pressure in the cryostat, ranging from 100 kPa to 200 kPa. Moreover, field utilization factor was calculated between sphere and plane electrode systems by a finite element method analysis. The electric field criterion of LN2 as insulation media was calculated from correlation between the experimental results and the field utilization factor. In the future, these results can be applied as the design parameter of electrical insulation for developing high voltage superconducting machines.
KW - Electrical insulation for high voltage superconducting machines
KW - Field utilization factor
KW - Lightning impulse dielectric experiment
KW - Liquid nitrogen insulation media
KW - Sphere and plane electrode systems
UR - http://www.scopus.com/inward/record.url?scp=80054992673&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=80054992673&partnerID=8YFLogxK
U2 - 10.1016/j.physc.2011.05.242
DO - 10.1016/j.physc.2011.05.242
M3 - Article
AN - SCOPUS:80054992673
VL - 471
SP - 1581
EP - 1585
JO - Physica C: Superconductivity and its Applications
JF - Physica C: Superconductivity and its Applications
SN - 0921-4534
IS - 21-22
ER -