Title |
Breakdown Characteristics of Liquid Nitrogen Induced by Quench |
Authors |
김영석(Kim, Yeong-Seok) ; 정종만(Jeong, Jong-Man) ; 곽민환(Gwak, Min-Hwan) ; 정순용(Jeong, Sun-Yong) ; 김상현(Kim, Sang-Hyeon) |
Keywords |
High T_c Superconductor ; Electrical Breakdown ; LN_2 ; Quench ; Thermal Bubble |
Abstract |
Electrical breakdown characteristics of liquid nitrogen(LN_2) used as both coolant and insulator for high T_c superconductor system are very important. This paper presents dynamic breakdown characteristics fo LN_2 by quench phenomena of thermal bubble under high electric field. Experimental results revealed dynamic breakdown voltage fell down drastically compared with the static breakdown voltage without the quench. Because of increasing heat power, bubble size becomes big and breakdown voltage decreases. The breakdown voltage mechanism of LN_2 depends on thermal bubble effect. In the Electrode arrangement, electrical breakdown voltage of horizontal arrangement appears lower than that of vertical arrangement. Also, we observed the behavior of thermal bubbles in LN_2 which were generated after quench using camera. |