Title :
Surface flashover characteristic of disc-type spacer system initiated by wedge shaped gas gap and its improvement
Author :
Hama, H. ; Yamamoto, H. ; Sakuma, S. ; Takatsuka, K. ; Yamauchi, T.
Author_Institution :
Mitsubishi Electric Corp., Amagasaki, Japan
fDate :
7/1/1993 12:00:00 AM
Abstract :
The surface flashover characteristics initiated by local field intensification are investigated for lightning impulse, switching impulse, and AC voltages, using disc-type model spacer systems with a wedge-shaped gas gap formed between the spacer flange and the earthed sheath end. The surface flashover voltages of the systems are evaluated by simple theory in SF/sub 6/ gas and compared with experimental results. Thin dielectric coating of a low-permittivity material on the sheath ends and the shielding of sheath ends which protrude inwardly are effective in improving the dielectric performance of the system.<>
Keywords :
earthing; electric breakdown of gases; electric strength; flashover; gaseous insulation; lightning protection; power system protection; sulphur compounds; switchgear; switching; AC voltages; SF/sub 6/; dielectric coating; dielectric performance; disc-type spacer; earthing; flange; lightning impulse; local field intensification; permittivity; power system protection; sheath ends; shielding; surface flashover characteristics; switchgear; switching impulse; wedge shaped gas gap;
Journal_Title :
Power Delivery, IEEE Transactions on
