Title :
Effect of electrode surface roughness on breakdown of SF/sub 6/ gas insulation
Author :
Oiu, Y. ; Li, R. ; Kuffel, F. ; Liu, Y.
Author_Institution :
Xi´´an Jiaotong Univ., China
Abstract :
The effect of electrode surface roughness on the breakdown voltage of SF/sub 6/ gas was studied using a large coaxial electrode system having an effective area of 6.2*10/sup 4/ mm/sup 2/ ( phi 49/135*400 mm) under AC voltages over the pressure range of 0.1-0.4 MPa. Three aluminium inner electrodes with different surface finish grades (R/sub Z/=0.86, 16 and 48 mu m) were used. For comparison purposes, copper and anodized aluminium inner electrodes were tested. The outer steel electrode was carefully polished so that no breakdown was initiated there. The experimental results show that the Pedersen criterion does not apply to large-area electrodes for which the effect of the gas pressure is more pronounced than that of the surface roughness. An empirical expression is given that take into account the effects of gas pressure and surface roughness separately.<>
Keywords :
electric breakdown of gases; electric strength; gaseous insulation; sulphur compounds; 0.1 to 0.4 MPa; 135 mm; 49 mm; AC voltages; Al electrodes; Al-Al/sub 2/O/sub 3/ electrodes; Cu electrodes; Pedersen criterion; SF/sub 6/; SF/sub 6/ gas insulation; breakdown voltage; coaxial electrode system; effect of electrode surface roughness; empirical expression; experimental results; inner electrodes; large-area electrodes; outer steel electrode; pressure range; surface finish grades; Aluminum; Breakdown voltage; Coaxial components; Copper; Electric breakdown; Electrodes; Rough surfaces; Surface finishing; Surface roughness; Testing;
Conference_Titel :
Electrical Insulation, 1988., Conference Record of the 1988 IEEE International Symposium on
Conference_Location :
Cambridge, MA, USA
DOI :
10.1109/ELINSL.1988.13875
