Particle contamination in gas-insulated systems: new control methods and optimum SF/sub 6//N/sub 2/ mixtures
The feasibilities of two new separate techniques to control particle contamination in practical gas-insulated sytems were tested in a small-scale concentric cylinder geometry. In one technique an insulating coating was first formed on the particles in a contaminated system by low-pressure discharges in appropriate gases such as 1-C/sub 3/F/sub 6/ and c-C/sub 4/F/sub 8/. When SF/sub 6/ was subsequently introduced into the same system at practical pressure as the operating insulation, the considerable harm ordinarily caused by particles was found to be eliminated. The nature of the coating formed also on the electrodes in this process was studied, with the conclusion that the observed benefits were primarily due to coating on particles, not on electrodes. In the second technique the particles, moved randomly by electrical stress, struck and adhered to the surface of a tacky insulating solid material; they were subsequently encapsulated in a melt-resolidify cycle without electrical stress. This trapping technique was also found to eliminate the harmful effects of particles in SF/sub 6/ at practical pressure. A technique for producing a trapping material with temperature characteristics appropriate for practical apparatus was devised. The effect of particle contamination on the dielectric strength of SF/sub 6//N/sub 2/ mixtures was studied as a function of total pressure and percentage of each gas. Optimum total pressure (approx. 6 atm) and optimum percentages (60% SF/sub 6//40% N/sub 2/) were observed in breakdown tests in particle-contaminated concentric cylinder geometry.
- Research Organization:
- Oak Ridge National Lab., TN (USA); Tennessee Univ., Knoxville (USA)
- DOE Contract Number:
- AC05-84OR21400
- OSTI ID:
- 7119935
- Report Number(s):
- CONF-840403-4; ON: DE84011670
- Resource Relation:
- Conference: 4. international symposium on gaseous dielectrics, Knoxville, TN, USA, 29 Apr 1984
- Country of Publication:
- United States
- Language:
- English
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Related Subjects
43 PARTICLE ACCELERATORS
ELECTRICAL INSULATION
GASES
NITROGEN
PURIFICATION
SULFUR FLUORIDES
COATINGS
CONTAMINATION
DIELECTRIC MATERIALS
DIELECTRIC PROPERTIES
DUSTS
MIXTURES
DISPERSIONS
ELECTRICAL PROPERTIES
ELEMENTS
FLUIDS
FLUORIDES
FLUORINE COMPOUNDS
HALIDES
HALOGEN COMPOUNDS
MATERIALS
NONMETALS
PHYSICAL PROPERTIES
SULFUR COMPOUNDS
360603* - Materials- Properties
430303 - Particle Accelerators- Experimental Facilities & Equipment