Cooling system for superconducting generators

Abstract

Cooling system for superconducting generators [Solution] The cooling system for the superconducting machine includes a thermal shield, a cryocooler, and an elongated member. The cryocooler is thermally coupled to the thermal shield via at least one thermal bus bar and at least one flexible connector, and the at least one thermal bus bar is secured across the at least one flexible connector. The elongated member is secured to the at least one thermal bus bar and the thermal shield such that the at least one thermal bus bar is positioned to minimize a length of the at least one flexible connector.

Description

[Technical Field]

[0001] FIELD OF THE DISCLOSURE The present disclosure relates to superconducting machines, and more particularly to improved cooling systems for superconducting machines. [Background technology]

[0002] Wind turbines are gaining attention as an environmentally safe and relatively inexpensive alternative energy source. Due to this growing interest, significant efforts have been made to develop reliable and efficient wind turbines. A wind turbine typically includes multiple rotor blades connected to a turbine shaft via a rotor hub. The rotor hub is located atop a tubular tower or base. Utility-grade wind turbines (i.e., wind turbines designed to supply power to the electric grid) can have large rotors (e.g., greater than 100 meters in diameter). The rotor blades convert wind energy into rotational torque or force that drives a generator that is rotationally coupled to the rotor.

[0003] Low-reactance machines (such as superconducting generators) are being considered for use in wind turbine installations, particularly offshore installations. These machines use a superconducting field winding and an assembly of armature coils, a cooling system, and non-magnetic teeth positioned between the coils within the armature. In certain designs, superconducting generators differ from conventional machine (e.g., conventional non-superconducting generator) configurations in that they include an armature winding assembly that rotates within a superconducting magnetic field assembly, which in turn includes a cryostat with the superconducting field coil within the cryostat.

[0004] During operation, superconducting magnet windings must be cooled below their critical temperature (the temperature at which the winding material changes from its normal resistive state and becomes a superconductor). Typically, the windings are cooled well below their critical temperature because the lower the temperature, the better the superconducting winding works. Furthermore, at lower temperatures, the superconducting windings can withstand higher currents and magnetic fields without reverting to a non-superconducting state. Therefore, liquid or mechanical cooling is commonly used to maintain the windings at a temperature sufficient to maintain their superconductivity. In liquid cooling, liquid helium can be used as the coolant, and its boiling point, 4.2 Kelvin, is below the critical temperature of most winding materials. Thus, the superconducting magnet and liquid helium are contained in an insulated vessel called a cryostat. Alternatively, mechanical cooling may involve cooling the superconducting magnet using a two-stage mechanical refrigeration system.

[0005] To improve the efficiency of cooling, various components of the cooling system and superconducting generator may be located in separate areas within the superconducting machine, allowing the components to be maintained at different temperatures. This separation of components may reduce unwanted heat transfer between parts, although consideration must be given to displacement and movement between such components due to thermal expansion and contraction.

[0006] Additionally, the fastening of different components together to form the cooling system can result in undesirable thermal contact resistance, which, if increased beyond a certain threshold, can cause the superconducting generator to operate suboptimally or the windings to operate in a non-superconducting state.

[0007] SUMMARY OF THE INVENTION Accordingly, the present disclosure is directed to an improved cooling system for a superconducting generator that addresses the aforementioned problems. [Prior art documents] [Patent documents]

[0008] [Patent Document 1] U.S. Patent No. 5,759,960 Summary of the Invention

[0009] Aspects and advantages of the present disclosure will be set forth in part in the description that follows, or may be obvious from the description, or may be learned by practice of the present disclosure.

[0010] In one aspect, the present disclosure is directed to a cooling system for a superconducting machine. The cooling system includes a thermal shield, a cryocooler, and an elongated member. The cryocooler is thermally coupled to the thermal shield via at least one thermal bus bar and at least one flexible connector, and the at least one thermal bus bar is secured across the at least one flexible connector. The elongated member is secured to the at least one thermal bus bar and the thermal shield in a manner that positions the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector.

[0011] In an embodiment, the elongate member includes at least one bend.

[0012] In a further embodiment, the at least one bend defines an angle in the range of about 30 degrees to about 150 degrees.

[0013] In a further embodiment, the elongate member includes multiple member components secured together to form at least one bend.

[0014] In other embodiments, at least a portion of the elongate member is integral with at least one thermal bus bar.

[0015] In yet a further embodiment, the elongate member is a separate component from the at least one thermal busbar.

[0016] In other additional embodiments, the at least one flexible connector includes a plurality of flexible connectors, wherein the elongate member includes a twisted portion that includes a wider surface to allow the plurality of flexible connectors to have approximately the same length.

[0017] In yet additional embodiments, the at least one flexible connector comprises a length ranging from about 50 millimeters (mm) to less than about 300 mm.

[0018] In yet other embodiments, the at least one flexible connector comprises one of a braided wire, a foil member, or a heat pipe.

[0019] In yet another embodiment, the extension member defines any of an L-shape, a U-shape, an I-shape, or an S-shape.

[0020] In another aspect, the present disclosure is directed to a method of cooling a superconducting machine. The method includes circumferentially disposing a heat shield around a cold mass of a superconducting device. The method also includes thermally coupling a cryocooler to the heat shield via a plurality of flexible connectors. The method further includes securing a thermal bus bar across the plurality of flexible connectors. The method further includes securing an elongated member to the thermal bus bar and the heat shield, wherein the elongated member positions the thermal bus bar relative to the cryocooler in a position that minimizes a length of the plurality of flexible connectors. The method further includes operating the cryocooler to cool the superconducting machine.

[0021] In yet another embodiment, the present disclosure is directed to a superconducting machine. The superconducting machine includes a cold mass, a thermal shield, a cryocooler, and an elongated member. The cold mass includes a plurality of superconducting coils. The thermal shield encases the cold mass. The cryocooler is thermally coupled to the thermal shield via at least one thermal bus bar and at least one flexible connector, with the at least one thermal bus bar secured across the at least one flexible connector. The elongated member is secured to the at least one thermal bus bar and the thermal shield in a manner that positions the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector.

[0022] These and other features, aspects, and advantages of the present disclosure will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to explain the principles of the disclosure. [Brief explanation of the drawings]

[0023] A full and enabling disclosure of the present disclosure, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the accompanying figures. [Figure 1] 1 illustrates an interior, perspective view of an embodiment of a nacelle of a wind turbine having a superconducting machine according to the present disclosure. [Figure 2] 1 shows a perspective view of an embodiment of a superconducting machine according to the present disclosure; [Figure 3] 1 shows an internal, perspective view of an embodiment of a superconducting machine. [Figure 4] 1 shows a simplified cross-sectional view of a superconducting machine according to the present disclosure. [Figure 5] 1 shows a partial internal view of one embodiment of a superconducting machine according to the present disclosure, particularly showing details of the cooling system of the superconducting machine. [Figure 6] 1 illustrates a partial perspective view of an embodiment of a heat shield for a superconducting machine according to the present disclosure. [Figure 7A-7C]In accordance with the present disclosure, various embodiments of elongate members that can be secured to the thermal bus bars and heat shields of a superconducting machine are shown to position the thermal bus bars in a location that minimizes the length of the flexible connector. [Figure 8] 1 illustrates a flow diagram of an example method for cooling a superconducting machine according to the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0024] Reference will now be made in detail to the embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, and not as a limitation of the invention. Indeed, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For example, features illustrated or described as part of one embodiment can be used with another embodiment to yield still a further embodiment. It is therefore intended that the present invention cover such modifications and variations as come within the scope of the appended claims and their equivalents.

[0025] Terms such as "coupled," "fixed," and "attached," unless otherwise specified herein, refer to both direct coupling, fixing, or attachment, and indirect coupling, fixing, or attachment through one or more intermediate components or features.

[0026] In general, the present disclosure is directed to a cooling system for a superconducting generator. In embodiments, for example, the superconducting generator may include a heat shield, a cryocooler, and an elongated member. The cryocooler is thermally coupled to the heat shield by a thermal bus bar and at least one flexible connector. Further, in embodiments, the thermal bus bar is secured across the flexible connector(s). Thus, an elongated member is secured to the thermal bus bar and the heat shield to position the thermal bus bar at a location where the length of the flexible connector is minimized. Thus, the length of the flexible connector can be minimized, thereby reducing thermal conduction losses and improving the efficiency of the cooling system.

[0027] Referring now to the figures, FIG. 1 illustrates an interior, perspective view of a wind turbine nacelle having a superconducting machine 10 according to the present disclosure. As illustrated, superconducting machine 10 may include an armature winding assembly 12, a field winding assembly 14, a plurality of conducting coils 16 (such as superconducting coils or non-superconducting coils), and an insulated vacuum vessel 18. Thus, in an embodiment, field winding assembly 14 may be a stationary component of superconducting machine 10, with a first electromagnetic component configuration in the form of conducting coils 16 providing a magnetic field around which armature winding assembly 12, with a second electromagnetic component configuration, rotates. However, it should be understood that in other embodiments, armature winding assembly 12 may instead be stationary while field winding assembly 14 rotates.

[0028] 2-4, various views of an embodiment of a superconducting machine 10 are illustrated in accordance with the present disclosure. In particular, FIG. 2 illustrates a perspective view of an embodiment of a superconducting machine 10 in accordance with the present disclosure, FIG. 3 illustrates an internal, perspective view of an embodiment of a superconducting machine 10 in accordance with the present disclosure, FIG. 4 illustrates a simplified cross-sectional view of a superconducting magnet in accordance with the present disclosure, and FIG. 5 illustrates a partial internal view of an embodiment of a cooling system in accordance with the present disclosure.

[0029] As discussed, it should be understood that such superconducting machines described herein may be used in a variety of devices or applications, and in particular, the superconducting machines may include or apply to, but should not be construed as being limited to, renewable energy (e.g., wind power), magnetic resonance imaging (MRI) machines, nuclear magnetic resonance (NMR) spectrometers, superconducting generators or motors, non-superconducting generators or motors, mass spectrometers, nuclear fusion reactors, particle accelerators, levitation, guidance, and propulsion, and the like.

[0030] As shown particularly in FIGS. 2-5, superconducting machine 10 includes an insulated vacuum vessel 18, commonly referred to as a cryostat. As used herein, cryostat generally refers to a device used to maintain low, cryogenic temperatures. Also shown, superconducting machine 10 generally includes a cold mass 28, a heat shield 30 circumferentially surrounding cold mass 28, and a cooling system 32. In further embodiments, cold mass 28 may be a stationary component, such as field winding assembly 14, which provides a stationary magnetic field around which armature winding assembly 12 rotates. Cold mass 28 may also include a plurality of conductive coils 16 (FIG. 1). Further, by way of example, vacuum vessel 18 may be a non-rotatable component that supports field winding assembly 14. Thus, in such an embodiment, rotatable components may be oriented to rotate relative to non-rotating components during operation of superconducting machine 10. In such an embodiment, as shown in FIG. 4, heat shield 30 is configured to shield and / or block radiation (as indicated by arrows 34) from vacuum vessel 18.

[0031] Still referring to FIGS. 2-5, the refrigeration system 32 is disposed within the vacuum vessel 18 and supported by an internal structure 38 (FIG. 3), and is configured to supply a cooling fluid 35, such as a cryogen, to at least one superconducting circuit 36 ​​or coil that is in fluid communication with one or more cryogen tanks 40. Thus, in such an embodiment, the vacuum vessel 18 insulates the superconducting circuit 36 ​​such that the superconducting circuit 36 ​​may be cooled to near absolute zero, e.g., down to 10 Kelvin (K), and preferably down to 4 K. For example, in an embodiment, the superconducting circuit 36 ​​may include a plurality of conduits 42 that carry cryogen from the cryogen tanks 40 to the internal structure 38. More specifically, as shown, the superconducting circuit 36 ​​may be arranged in a coil and configured to generate a magnetic field. As particularly shown in FIG. 2, the superconducting machine 10 may further include a power source 44 for energizing the superconducting circuit 36.

[0032] Therefore, in its superconducting state, the superconducting circuit 36 ​​has no electrical resistance and can therefore conduct much larger currents and generate stronger magnetic fields than ordinary wire. Furthermore, during operation, the superconducting circuit 36 ​​must be cooled below its critical temperature, which is the temperature at which the wire material changes from its normal resistive state and becomes a superconductor. Typically, the superconducting circuit 36 ​​is cooled to a temperature significantly below its critical temperature because the lower the temperature, the better the superconducting winding will perform and the higher the current and magnetic field it can withstand without reverting to a non-superconducting state.

[0033] Further, as shown, the cooling system 32 may be secured to the heat shield 30 of the superconducting machine 10 via at least one thermal bus bar 46. Also as shown, the thermal bus bar 46 is thermally coupled to the heat shield 30 and the cryocooler 48. In such an embodiment, for example, as shown in FIG. 4, the cryocooler 48 is thermally coupled to the heat shield 30 via the thermal bus bar 46 and at least one flexible connector 110 (FIGS. 5 and 6). Further, the thermal bus bar 46 is secured across the flexible connector 110. In such an embodiment, the flexible connector 110 may be a braided wire, a foil member, or a heat pipe. Thus, heat is removed to the cooling system 32 via the thermal bus bar 46. Also, as particularly shown in FIG. 5, the cooling system 32 further includes an elongated member 102 secured to the thermal bus bar 46 and the heat shield 30 to position the thermal bus bar 46 in a position that minimizes the length of the flexible connector 110. In particular, as shown in FIG. 5 , the elongated member 102 is secured at a first end 99 to the thermal bus bar 46 and at a second end 101 to the heat shield 30. For example, as shown in FIG. 5 , the first end of the elongated member 102 may be secured to the thermal bus bar 46 via a first fastener 106. Similarly, as shown, the second end 101 of the elongated member 102 may be secured to the heat shield 30 via a second fastener 107. In such an embodiment, the elongated member 102 may be a separate component from the thermal bus bar 46. Furthermore, the elongated member 102 may be sized such that the second end 101 extends the entire length of the heat shield 30 from the vacuum vessel 18. This allows the elongated member 102 to better extract heat from the heat shield 30 by transferring heat axially from the heat shield 30 to the thermal bus bar 46. Also, by sizing the extension member 102 in this manner, it may be possible for the extension member 102 to be able to maintain gas flow with the cryocooler 48 and the cryogen tank 40 .

[0034] If the flexible connector 110 is too long, the delta temperature and thermal conduction losses of the thermal bus bar 46, the flexible connector 110, or other components of the cooling system 32 may be too high, resulting in a loss of cooling power. Therefore, shortening the length of the flexible connector 110 may be useful to minimize the delta temperature of such components. Thus, the elongated member 102 may be configured to effectively shorten the length of the flexible connector 110, which may also result in a reduction in thermal contact resistance. For example, in embodiments, the elongated member 102 may enable the length of the flexible connector 110 to be less than about 50 millimeters (mm) to about 300 mm.

[0035] Additionally, in certain embodiments, elongate member 102 may be a monolithic component, such as a pedestal arrangement, or may be a segmented component formed from multiple member component parts. For example, if elongate member 102 is segmented, it may include a first member component 121 attached to heat shield 30 and a second member component 122 attached to first member component 121 and thermal bus bar 46. Thus, if elongate member 102 is segmented (as shown in FIG. 5 ), the member components may be joined together at one or more hinge joints 113, so that the shape of elongate member 102 can be modified as needed to connect elongate member 102 to heat shield 30 between flexible connectors 110. However, if elongate member 102 is a monolithic component, it may be a single, continuous piece of material.

[0036] Additionally, in certain embodiments, the elongate member 102 described herein can have any suitable shape with any number of bends to effectively shorten the length of the flexible connector 110. For example, as shown in Figures 5 and 7, the elongate member 102 can include at least one bend 114.

[0037] However, the elongated member 102 need not have a bend 114. For example, referring now to FIG. 6 , the elongated member 102 may take the form of a pedestal that is a free-standing I-shaped member that extends from the thermal bus bar 46 and connects to the flexible connector 110. An elongated member 102 without a bend may be particularly useful when the distance between the thermal bus bar 46 and the cryocooler 48 is sufficient to reduce the delta temperature and thermal contact resistance. In this configuration, the flexible connector 110 may be attached to the elongated member 102. However, if a shorter distance is required, a bend can be provided.

[0038] In such embodiments where a bend 114 is provided, the bend 114 may define an angle (i.e., between the two member components 116, 118 of the elongate member 102) ranging from about 30 degrees to about 150 degrees. Thus, by providing at least one bend 114 in the elongate member 102, various shapes can be formed to route the elongate member 102 from the flexible connector 110 to the heat shield 30. For example, in embodiments, as shown in FIGS. 5 and 7B, the elongate member 102 may have a generally J-shape (or U-shape) to route the elongate member 102 from the flexible connector 110 to the heat shield 30. Also, with reference to FIGS. 7A-7C, example shapes of the elongate member 102 according to the present disclosure are provided. In particular, as shown in FIG. 7A, the elongate member 102 has a generally S-shape or Z-shape. In another embodiment, as shown in FIG. 7C, the elongate member 102 has a generally L-shape. 7C , the elongated member 102 may include a twist 120 or twisted portion to further assist in shortening the length of the flexible connector 110. For example, the twist 120 or twisted portion may result in the elongated member 102 more directly facing the flexible connector 110 or thermal bus bar 46, allowing the flexible connector or thermal bus bar 46 to be uniformly attached to the elongated member 102.

[0039] Additionally, in certain embodiments, the twists 120 are configured to provide a larger surface area for the flexible connectors 110. The larger surface area may allow the flexible connectors 110 to be attached at approximately the same length. By making the flexible connectors 110 approximately the same length, the thermal contact resistance can be uniform across all connectors, thereby increasing the overall efficiency of the cooling system.

[0040] Referring now to FIG. 8 , a flow diagram of one embodiment of a method for cooling a generator according to the present disclosure is shown. Generally, the method 200 is described herein with reference to the superconducting machine 10 and associated cooling system 32 described herein with reference to FIGS. 1-7 . However, those skilled in the art should understand that the disclosed method 200 may generally be utilized with any superconducting machine having any suitable configuration. Furthermore, while FIG. 8 depicts steps performed in a particular order for purposes of illustration and discussion, the methods discussed herein are not limited to any particular order or arrangement. Those skilled in the art will understand, using the disclosure provided herein, that various steps of the methods disclosed herein can be omitted, rearranged, combined, and / or adapted in various ways without departing from the scope of the present disclosure.

[0041] As shown at (202), the method 200 includes circumferentially disposing a heat shield around a cold mass of a superconducting machine. As shown at (204), the method 200 includes thermally coupling a cryocooler to the heat shield via a plurality of flexible connectors. As shown at (206), the method includes securing a thermal bus bar across the plurality of flexible connectors. As shown at (208), the method 200 includes securing an elongated member to the thermal bus bar and the heat shield, such that the elongated member positions the thermal bus bar relative to the cryocooler in a position that minimizes the length of the plurality of flexible connectors. As shown at (210), the method 200 includes operating the cryocooler to cool the generator.

[0042] Those skilled in the art will recognize the interchangeability of various features from different embodiments. Similarly, the steps and features of the various methods described, and other known equivalents to each such method and feature, can be mixed and matched by one of ordinary skill in the art to construct additional systems and techniques in accordance with the principles of the present disclosure. Of course, it should be understood that not all such objects or advantages described above may be achieved in accordance with a particular embodiment. Thus, for example, those skilled in the art will recognize that the systems and techniques described herein can be embodied or implemented in a manner that achieves or optimizes one advantage or group of advantages as taught herein, but does not necessarily achieve other objects or advantages as taught or suggested herein.

[0043] Various aspects and embodiments of the present invention are defined by the following numbered clauses: [Embodiment 1] A heat shield and a cryocooler thermally coupled to the heat shield via at least one thermal bus bar and at least one flexible connector, the at least one thermal bus bar being secured across the at least one flexible connector; and an elongated member secured to the at least one thermal bus bar and the heat shield to position the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector. Cooling system for superconducting machines. [Embodiment 2] 10. The cooling system of claim 1, wherein the elongate member includes at least one bend. [Embodiment 3] 3. The cooling system of claim 2, wherein the at least one bend defines an angle in the range of about 30 degrees to about 150 degrees. [Embodiment 4] 4. The cooling system of claim 2, wherein the elongated member includes a plurality of member components secured together to form the at least one bend. [Embodiment 5] 10. The cooling system of any preceding clause, wherein at least a portion of the elongate member is integral with the at least one thermal busbar. [Embodiment 6] 10. The cooling system of any preceding clause, wherein the elongate member is a separate component from the at least one thermal busbar. [Embodiment 7] 10. The cooling system of claim 1, wherein the at least one flexible connector includes a plurality of flexible connectors, and the extension member includes a twisted portion including a wider surface to enable the plurality of flexible connectors to have approximately the same length. [Embodiment 8] 10. The cooling system of any preceding clause, wherein the at least one flexible connector comprises a length in a range of about 50 millimeters (mm) to less than about 300 mm. [Embodiment 9] 10. The cooling system of claim 1, wherein the at least one flexible connector comprises one of a braided wire, a foil member, or a heat pipe. [Embodiment 10] 10. The cooling system of any preceding clause, wherein the elongate member defines one of an L-shape, a U-shape, an I-shape, or an S-shape. [Embodiment 11] 1. A method of cooling a superconducting machine, comprising: circumferentially disposing a heat shield around a cold mass of the superconducting machine; thermally coupling the cryocooler to the heat shield via a plurality of flexible connectors; securing a thermal bus bar to the plurality of flexible connectors; securing an elongated member to the thermal bus bar and the heat shield, the elongated member positioning the thermal bus bar relative to the cryocooler that minimizes a length of the plurality of flexible connectors; and operating the cryocooler to cool the superconducting machine. The method. [Embodiment 12] 12. The method of claim 11, wherein the elongate member includes at least one bend. [Embodiment 13] 13. The method of clause 12, wherein the at least one bend defines an angle in the range of about 30 degrees to about 150 degrees. [Embodiment 14] 14. The method of claim 12-13, wherein the elongate member comprises a plurality of member components secured together to form at least one bend. [Embodiment 15] 15. The method of any one of claims 11 to 14, wherein the elongated member includes a twisted portion that includes a wider surface to allow multiple flexible connectors to have approximately the same length. [Embodiment 16] 16. The method of any one of claims 11 to 15, wherein the length of the plurality of flexible connectors comprises a range of from about 50 millimeters (mm) to less than about 300 mm. [Embodiment 17] 17. The method according to any one of claims 11 to 16, wherein the elongate member is integral with the thermal busbar. [Embodiment 18] 18. The method according to any one of items 11 to 17, wherein the plurality of flexible connectors include one of a braided wire, a foil member, or a heat pipe. [Embodiment 19] 19. The method of any one of clauses 11 to 18, wherein the elongate member defines at least one of an L-shape, a U-shape, an I-shape, or an S-shape. [Embodiment 20] A superconducting machine, a cold mass including a plurality of superconducting coils; A heat shield enveloping the cold mass, a cryocooler thermally coupled to the heat shield via at least one thermal bus bar and at least one flexible connector, the at least one thermal bus bar being secured across the at least one flexible connector; and an elongated member secured to the at least one thermal bus bar and the heat shield to position the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector. Superconducting machine.

[0044] This written description uses examples to disclose the disclosure, including the best mode, and also to enable any person skilled in the art to practice the disclosure, including making and using any devices or systems and performing any incorporating methods. The patentable scope of the disclosure is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they include structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims. [Explanation of symbols]

[0045] 10 Superconducting Machine 12 Armature Winding Assembly 14 Field Winding Assembly 16 Conducting coil 18 Insulated vacuum vessel 28 Cold Mass 30 Heat Shield 32 Cooling System 34 Arrow 35 Cooling fluid 36 Superconducting Circuits 38 Internal structure 40 Cryogen Tank 42 Conduit 44 Power supply 46 Thermal busbar 48 Cryocooler 99 First end 101 second end 102 Extension member 106 First Fastener 107 Second Fastener 110 Flexible Connector 113 Hinge joint 114 Bend 116 Component Elements 118 Component Elements 120 Twist 121 First member component 122 Second member component 200 ways

Claims

1. A heat shield and a cryocooler thermally coupled to the heat shield via at least one thermal bus bar and at least one flexible connector, the at least one thermal bus bar secured across the at least one flexible connector; and an elongated member secured to the at least one thermal bus bar and the heat shield to position the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector. Cooling system for superconducting machines.

2. The cooling system of claim 1 , wherein the elongated member includes at least one bend.

3. The cooling system of claim 2 , wherein the at least one bend defines an angle in the range of about 30 degrees to about 150 degrees.

4. The cooling system of claim 2 , wherein the elongated member comprises a plurality of member components secured together to form the at least one bend.

5. The cooling system of claim 1 , wherein at least a portion of the elongate member is integral with the at least one thermal bus bar.

6. The cooling system of claim 1 , wherein the elongate member is a separate component from the at least one thermal bus bar.

7. 2. The cooling system of claim 1, wherein the at least one flexible connector comprises a plurality of flexible connectors, and the elongated member comprises a twisted portion including a wider surface to enable the plurality of flexible connectors to have approximately the same length.

8. The cooling system of claim 1 , wherein the at least one flexible connector comprises a length ranging from about 50 millimeters (mm) to less than about 300 mm.

9. The cooling system of claim 1 , wherein the at least one flexible connector comprises one of a braided wire, a foil member, or a heat pipe.

10. The cooling system of claim 1 , wherein the elongated member defines one of an L-shape, a U-shape, an I-shape, or an S-shape.

11. A method for cooling a superconducting machine, circumferentially disposing a heat shield around a cold mass of the superconducting machine; thermally coupling the cryocooler to the heat shield via a plurality of flexible connectors; securing a thermal bus bar to the plurality of flexible connectors; securing an elongated member to a thermal bus bar and a heat shield, the elongated member positioning the thermal bus bar in a position relative to the cryocooler that minimizes a length of the plurality of flexible connectors; and operating the cryocooler to cool the superconducting machine. The method.

12. The method of claim 11 , wherein the elongated member includes at least one bend.

13. The method of claim 12 , wherein the at least one bend defines an angle in the range of about 30 degrees to about 150 degrees.

14. The method of claim 12 , wherein the elongate member comprises a plurality of member components secured together to form at least one bend.

15. The method of claim 11 , wherein the elongate member includes a twisted portion that includes a wider surface to allow multiple flexible connectors to have approximately the same length.

16. The method of claim 11 , wherein the lengths of the plurality of flexible connectors comprise a range of from about 50 millimeters (mm) to less than about 300 mm.

17. The method of claim 11 , wherein the elongate member is integral with the thermal bus bar.

18. The method of claim 11 , wherein the plurality of flexible connectors comprises one of a braided wire, a foil member, or a heat pipe.

19. The method of claim 11 , wherein the elongate member defines at least one of an L-shape, a U-shape, an I-shape, or an S-shape.

20. A superconducting machine, a cold mass including a plurality of superconducting coils; a thermal shield encasing the cold mass; a cryocooler thermally coupled to the heat shield via at least one thermal bus bar and at least one flexible connector, the at least one thermal bus bar secured across the at least one flexible connector; and an elongated member secured to the at least one thermal bus bar and the heat shield to position the at least one thermal bus bar in a position that minimizes a length of the at least one flexible connector. Superconducting machine.

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