Patent US5482919A successfully refreshed from Google Patents.
US5482919A
Expired / Lapsed
US
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Superconducting rotor
Assignee: American Superconductor Corp
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Filing: 1993-09-15
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Granted: 1996-01-09
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Expires: 2013-09-15
Abstract
Abstract The superconducting rotor includes at least one field coil made of a superconductor material having a given superconducting transition temperature. A cryocooler system is mounted for rotation with the rotor. The cryocooler includes a cold head portion mounted in heat transfer relation with the field coil to cool the field coil to a temperature below its transition temperature and includes a piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system. Heat is conducted away from the field coils by heat pipes or by conduction through high thermally conductive material. Mounting the cryocooler cold head for rotation with the rotor eliminates the use of a cryogenic liquid pool for rotor cooling.
Inventors
- 👤 Chandrashekhar H. Joshi
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 14:53
CPC Classifications
F; F25; F25B; F25B9/00; F25B9/14; F25D; F25D19/00; F25D19/006; H; H02; H02K; H02K55/00; H02K55/02; H02K55/04; H02K9/00; H02K9/22; H02K9/225; F25B2309/00; F25B2309/003; Y; Y02; Y02E; Y02E40/00; Y02E40/60; Y10; Y10S; Y10S505/00; Y10S505/825; Y10S505/876; Y10S505/877; Y10S505/878
Claims Analysis
Total Claims: 30
Claim 1
Independent Claim
89 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a superconductor material having a superconducting transition temperature; and a cryocooler system including a cold head mounted for rotation with the rotor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature and comprising a piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system.
Claim 2
Dependent Claim
89 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a superconductor material having a superconducting transition temperature; and a cryocooler system including a cold head mounted for rotation with the rotor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature and comprising a piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system.
Claim 3
Dependent Claim
93 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a superconductor material having a superconducting transition temperature; and a cryocooler system mounted for rotation with the rotor, the system including a cold head and a compressor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature comprising a piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system.
Claim 4
Dependent Claim
93 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a superconductor material having a superconducting transition temperature; and a cryocooler system mounted for rotation with the rotor, the system including a cold head and a compressor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature comprising a piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system.
Claim 5
Dependent Claim
28 words
The system of claim 1 or claim 2 wherein the coil and the cold head are in thermal contact with structure having a high coefficient of thermal conductivity.
Claim 6
Dependent Claim
23 words
The system of claim 1 or claim 2 further including at least one heat pipe disposed between the coil and the cold head.
Claim 7
Dependent Claim
31 words
The system of claim 1 further including a non-rotating compressor for delivering high pressure working fluid to the cold head and for receiving lower pressure working fluid from the cold head.
Claim 8
Dependent Claim
19 words
The system of claim 5 wherein the compressor and cold head are in fluid communication through a rotary joint.
Claim 9
Dependent Claim
29 words
The system of claim 5 wherein the high pressure working fluid is conveyed in a first line disposed within a second line which conveys the lower pressure working fluid.
Claim 10
Dependent Claim
30 words
The system of claim 3 wherein the structure is adapted to support the coil and includes a plurality of axially spaced apart annular members connected by axially extending longitudinal members.
Claim 11
Dependent Claim
17 words
The system of claim 4 wherein a portion of the heat pipe is embedded in the coil.
Claim 12
Dependent Claim
18 words
The system of claim 2 wherein the compressor is powered by electricity delivered through an electrical slip-ring coupling.
Claim 13
Dependent Claim
19 words
The system of claim 1 or claim 2 wherein the cold head and the rotor have coincident longitudinal axes.
Claim 14
Dependent Claim
22 words
The system of claim 1 or claim 2 wherein the cold head includes a reciprocating piston/regenerator driven by a linear motor assembly.
Claim 15
Dependent Claim
17 words
The system of claim 1 or claim 2 wherein the cryocooler system is a two stage cryocooler.
Claim 16
Dependent Claim
17 words
The system of claim 1 or claim 2 wherein the cryocooler system is a single stage cryocooler.
Claim 17
Dependent Claim
19 words
The system of claim 1 or claim 2 wherein the superconducting material has a transition temperature below 35 K.
Claim 18
Dependent Claim
19 words
The system of claim 1 or claim 2 wherein the superconducting material has a transition temperature above 35 K.
Claim 19
Dependent Claim
24 words
The system of claim 1 or claim 2 wherein the working fluid is selected from the group comprising helium, neon, nitrogen, hydrogen and oxygen.
Claim 20
Dependent Claim
33 words
The system of claim 1 or claim 2 wherein the cryocooler system operates on a thermodynamic cycle selected from the group comprising the Gifford-McMahon cycle, the Stirling cycle and the pulse tube cycle.
Claim 21
Dependent Claim
95 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a high temperature superconductor material having a superconducting transition temperature; a compressor and a cryocooler cold head including a reciprocating piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system, the cold head and compressor mounted for rotation with the rotor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature.
Claim 22
Dependent Claim
95 words
Superconducting rotor system comprising: a rotor including at least one field coil made of a high temperature superconductor material having a superconducting transition temperature; a compressor and a cryocooler cold head including a reciprocating piston/regenerator adapted to allow passage of a working fluid at a mass flow rate which is substantially uniform over the cross-section of the piston/regenerator during operation of the system, the cold head and compressor mounted for rotation with the rotor, the cold head in heat transfer relation with the coil to cool the coil to a temperature below its transition temperature.
Claim 23
Dependent Claim
23 words
The system of claim 1 or claim 2 or claim 19 wherein the cryocooler system maintains the temperature of the coil below 77k.
Claim 24
Dependent Claim
25 words
The system of claim 1 or claim 2 or claim 19 wherein the cryocooler system maintains the temperature of the coil below approximately 50 K.
Claim 25
Dependent Claim
17 words
The system of claim 4 wherein the heat pipe includes a wick material on its inside surface.
Claim 26
Dependent Claim
20 words
The system of claim 1 or claim 2 or claim 19 wherein the superconductor material is a superconducting ceramic oxide.
Claim 27
Dependent Claim
37 words
The system of claim 1 or claim 2 wherein the piston/regenerator includes a plurality of axially oriented passages, the sizes and locations of the passages selected to provide the substantially cross-sectionally uniform working fluid mass flow rate.
Claim 28
Dependent Claim
38 words
The system of claim 24 wherein the total cross-sectional area of the passages at a radial position varies in a substantially inverse relation to radial position of the passage measured from the axis of symmetry of the piston/regenerator.
Claim 29
Dependent Claim
23 words
The system of claim 1 or claim 2 wherein the piston/regenerator has a high radial thermal conductivity and a low axial thermal conductivity.
Claim 30
Dependent Claim
29 words
The system of claim 26 wherein the piston/regenerator comprises a plurality of high thermal conductivity disks, each disk spaced from an adjacent disk by a low thermal conductivity separator.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1999-01-08 | 1999-07-10 | 2000-01-09 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 2003-01-08 | 2003-07-10 | 2004-01-09 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2007-01-08 | 2007-07-10 | 2008-01-09 | $7700.00 | Window Closed / Lapsed |