Vacuum Studies of a Prototype Composite Coil Dewar for HTSC Transformers

Conference · Fri Jan 01 00:00:00 EST 2010

OSTI ID:1054971

Schwenterly, S W ^[1]; Zhang, Y. ^[2]; Pleva, Ed ^[3]; Rufer, M. ^[4]

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1. ORNL
2. Oak Ridge National Laboratory (ORNL)
3. Waukesha Electric Systems, Waukesha, WI
4. Scorpius Space Launch Co.

Oak Ridge National Laboratory (ORNL) is collaborating with Waukesha Electric Systems (WES) to develop a high-temperature superconducting (HTSC) utility power transformer with primary and secondary coils cooled by liquid nitrogen. Since the vacuuminsulated cryogenic coil dewar surrounds the magnetic core limb and cannot form a shorted turn, non-conductive materials are required. Two test vessels and a small prototype dewar have been fabricated by Scorpius Space Launch Company with epoxy/fiberglass composites, using their proprietary PRESSURMAXX vessel technology. The effects of pumping time, bakeout temperature, and cryogenic vessel temperature on vacuum outgassing rates have been investigated. Outgassing rates of the individual materials used in vessel construction have also been measured. The results will be scaled up to determine the required pumping capacity for a full-size 25-MVA commercial transformer dewar.

• Research Organization: Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
• Sponsoring Organization: OE USDOE - Office of Electric Transmission and Distribution
• DOE Contract Number: DE-AC05-00OR22725
• OSTI ID: 1054971
• Resource Relation: Conference: Cryogenic Engineering Conference and International Cryogenic Materials Conference (CEC/ICMC 2009), Tucson, AZ, USA, 20090628, 20090702
• Country of Publication: United States
• Language: English

Related Subjects

Cryogenic tanks
thermal insulation
composites
multilayer insulatoin
heat transfer
vacuum
liquid nitrogen boiloff