Title :
Cathode electric field preceding flashover of a bridged vacuum gap
Author :
Naruse, Hiroki ; Ooura, Yousuke ; Saito, Hiroshi ; Sakaki, Masayuki ; Yamamoto, Osamu
Author_Institution :
Dept. of Electr. Eng., Kyoto Univ., Kyoto, Japan
Abstract :
This paper reports the characteristic of flashover voltage and its relation to the electric field strength on a cathode. The test gap consisted of parallel disc electrodes bridged by an insulating solid cylinder made of Al2O3. The electric field just before the flashover, which included an applied geometrical field component Eg and a surface charge component Es, was measured by using a ring type electrostatic probe embedded in the cathode made of aluminum. As a result, we have found, although the rate of each field component varies, that the total electric field strength (Eg +Es) is in the rage between 5.4 to 7.5 kVmm-1 and is almost constant irrespective of neither the insulator length nor its surface roughness, which ranges from 5 to 50 mm and 0.2 to 6 μm, respectively.
Keywords :
cathodes; electric fields; flashover; surface charging; applied geometrical field component; bridged vacuum gap; cathode electric field; electric field strength; flashover voltage; insulating solid cylinder; parallel disc electrodes; ring type electrostatic probe; surface charge component; Cathodes; Electric fields; Flashover; Insulators; Rough surfaces; Surface roughness;
Conference_Titel :
Electric Power Equipment - Switching Technology (ICEPE-ST), 2013 2nd International Conference on
Conference_Location :
Matsue
DOI :
10.1109/ICEPE-ST.2013.6804360