Plasma development in the early phase of vacuum surface flashover
- Texas Tech Univ., Lubbock, TX (United States). Dept. of Electrical Engineering and Physics
The primary physical mechanism responsible for charge-carrier amplification, in a developing surface discharge, has eluded conclusive identification for decades. This paper describes the results of experiments to directly detect charge-carriers, above the dielectric surface, within the developing discharge. Free electrons are detected by measuring the deflection of a laser beam, focused to a 20 [mu]m 1/e diameter, with an angular sensitivity of 0.18 mV/[mu]rad and a risetime of 6 ns. The estimated detection threshold for electrons in the developing discharge is 10[sup 16] cm[sup [minus]3] to 10[sup 17] cm[sup [minus]3]. A streak camera is used to gather spatial information regarding luminous processes with a maximum resolution of 25 [mu]m and 0.6 ns. Current measurements have a sub-nanosecond response time and a detection threshold of 100 mA. Laser deflection measurements demonstrate the rapid development of a particle gradient, generally within 10 [mu]m of the surface near the cathode and in the range of 75 to 175 [mu]m from the surface near the anode, during the developing discharge. Streak camera measurements demonstrate the formation of an intense, visible emission, 25 to 50 [mu]m in diameter, located near the insulator surface, during the formation of the discharge. These results imply that charge-carrier amplification occurs above the surface of the insulator, in a region of neutral particles desorbed or otherwise ejected from the insulator surface.
- OSTI ID:
- 6617166
- Journal Information:
- IEEE Transactions on Plasma Science (Institute of Electrical and Electronics Engineers); (United States), Vol. 22:6; ISSN 0093-3813
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
ELECTRICAL INSULATORS
FLASHOVER
CHARGE CARRIERS
DIAGNOSTIC TECHNIQUES
ELECTRICAL EQUIPMENT
EXPERIMENTAL DATA
PLASMA PRODUCTION
CURRENTS
DATA
ELECTRIC CURRENTS
ELECTRIC DISCHARGES
EQUIPMENT
INFORMATION
NUMERICAL DATA
240000* - Power Transmission & Distribution- (1990-)