Liquid helium boil-off measurements of heat leakage from sinter-forged BSCCO current leads under DC and AC conditions

Conference · Thu Jun 01 04:00:00 EDT 1995

OSTI ID:93465

Cha, Y S; Niemann, R C; Hull, J R; Youngdahl, C A; Lanagan, M T ^[1]; Nakade, M; Hara, T ^[2]

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1. Argonne National Lab., IL (United States)
2. Tokyo Electric Power Co., Yokohama (Japan)

Liquid helium boil-off experiments are conducted to determine the heat leakage rate of a pair of BSCCO 2223 high-temperature superconductor current leads made by sinter forging. The experiments are carried out in both DC and AC conditions and with and without an intermediate heat intercept. Current ranges are from 0-500 A for DC tests and 0-1,000 A{sub rms} for AC tests. The leads are self-cooled. Results show that magnetic hysteresis (AC) losses for both the BSCCO leads and the low-temperature superconductor current jumper are small for the current range. It is shown that significant reduction in heat leakage rate (liquid helium boil-off rate) is realized by using the BSCCO superconductor leads. At 100 A, the heat leakage rate of the BSCCO/copper binary lead is approximately 29% of that of the conventional copper lead. Further reduction in liquid helium boil-off rate can be achieved by using an intermediate heat intercept. For example, at 500 K, the heat leakage rate of the BSCCO/copper binary lead is only 7% of that of the conventional copper lead when an intermediate heat intercept is used.

• Research Organization: Argonne National Lab., IL (United States)
• Sponsoring Organization: USDOE, Washington, DC (United States)
• DOE Contract Number: W-31109-ENG-38
• OSTI ID: 93465
• Report Number(s): ANL/ET/CP--84847; CONF-950722--1; ON: DE95014227
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
DEWARS
ELECTRIC CONDUCTORS
ENERGY LOSSES
HEAT
HEAT TRANSFER
HIGH-TC SUPERCONDUCTORS