Development of a Cryogenic Helium-Neon Gas Mixture Cooling System for Use in a Gd-Bulk HTS Synchronous Motor

Author

Felder, Brice ; Miki, Motohiro ; Deng, Zigang ; Tsuzuki, Keita ; Shinohara, Nobuyuki ; Izumi, Mitsuru ; Hayakawa, Hironao

Author_Institution

Tokyo Univ. of Marine Sci. & Technol., Tokyo, Japan

Volume

21

Issue

3

fYear

2011

fDate

6/1/2011 12:00:00 AM

Firstpage

2213

Lastpage

2216

Abstract

Temperature Superconductors (HTS) applied to rotating machines require an efficient cooling system. It is necessary to increase the maximum trapped flux density in the bulk HTS magnets and decrease the overall cooling time. In this paper, we added a gaseous helium phase to a condensed-neon closed-cycle thermosyphon. The latent heat of neon-film cooling is combined with helium´s high thermal conductivity. Different mixture proportions were evaluated in terms of resistance to variable heat loads. More helium decreased the temperature variation of the evaporator. The mixture was then used to cool down a 30 kW-grade gadolinium-bulk HTS synchronous motor. The eight bulk HTS conductors of the rotor were cooled to 40 K in less than six hours. The application of this thermosyphon is envisioned for larger rotating machines.

Keywords

cryogenics; gas mixtures; helium; high-temperature superconductors; neon; synchronous motors; thermal conductivity; HTS synchronous motor; He-Ne; condensed-neon closed-cycle thermosyphon; cryogenic helium-neon gas mixture cooling system; power 30 kW; temperature 40 K; temperature superconductor; thermal conductivity; thermosyphon; Cooling; Copper; Heating; Helium; High temperature superconductors; Magnetic heads; Temperature sensors; Closed-cycle thermosyphon; cryogenics; helium-neon mixture; superconducting rotating machines;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2010.2101573

Filename

5704209