VERTICAL-AXIS-TYPE WIND TURBINE EQUIPPED HIGH-TEMPERATURE SUPERCONDUCTING GENERATOR WITH BATCH IMPREGNATION COOLING STRUCTURE USING CRYOGEN

Abstract

The present invention relates to a vertical axis wind turbine equipped with a high-temperature superconducting generator having a batch impregnation cooling structure.

The vertical axis wind turbine is configured to allow the superconducting generator and accessory devices (a cooling system, a power conversion system, etc.) to be located under a turbine tower, whereas allowing only a rotary body with vertical blades to be located on the upper portion of the turbine tower, unlike a conventional horizontal axis wind turbine, thereby remarkably reducing a top-head weight of the wind turbine, greatly decreasing installation and maintenance costs, removing technical difficulties in large scale construction, and allowing a center of weight to move to a portion under the turbine tower so that if the vertical axis wind turbine is applied for floating offshore wind power generation, it advantageously ensures the miniaturization of a floating body and the stability of a floating posture.

Claims

1. A vertical axis wind turbine equipped with a high-temperature superconducting generator having a batch impregnation cooling structure using a cryogen, the vertical axis wind turbine comprising: the superconducting generator (100) having a rotor core (110) vertically standing up thereon, a rotor (120) provided by locating a high-temperature superconducting field coil in a circumferential direction of the rotor core (110), a stator (130) provided by locating a superconducting armature coil in such a way as to be spaced apart from the rotor (120) by a given distance, and a cryostat (140) adapted to accommodate the rotor core (110), the rotor (120), and the stator (130), as an integral module, therein and having a refrigerant circulation inlet pipe (141) and a refrigerant circulation outlet pipe (142) disposed on one side and the other side thereof to perform batch impregnation cooling for the superconducting generator (100) by means of a circulation refrigerant (introduced refrigerant is liquid and discharged refrigerant is gas) introduced from a cryogenic cooling system (300); a tower assembly (200) having a rotor shaft (210) connected to top end periphery of the rotor core (110) in such a way as to allow a top end portion thereof to extend to the outside of a top plate of the cryostat (140) so that the rotor shaft (210) is connected vertically to a main shaft (240) having vertical blades (230) by means of a shaft coupling (220), the main shaft (240) rotating inside a turbine tower (250) through support bearings (260); and the cryogenic cooling system (300) having a cooling chamber (320) in which a circulation type cooling pump (310) is disposed adapted to supply a liquid refrigerant to the cryostat (140) so that a vaporized gas refrigerant is collected, and a cryostat (330) and a helium compressor (340) connected to one side and the other side of the cooling chamber (320) through respective supply lines.

2. The vertical axis wind turbine according to claim 1, wherein the rotor core (110) and the rotor shaft (210) are connected to each other by means of a contact type exciter (150), and the contact type exciter (150) has a pair of current leads (151) conductive to the high-temperature superconducting field coil and a slip ring (152) and a brush (153) disposed on tops of the current leads (151) in such a way as to come into close contact with each other and be thus electrically connected to each other.

3. The vertical axis wind turbine according to claim 1, wherein the rotor core (110) and the rotor shaft (210) are connected to each other by means of a non-contact type exciter (160), and the non-contact type exciter (160) has a flux pump header (161) conductive to the high-temperature superconducting field coil and a permanent magnet (163) coupled to a flux pump rotor (162) and located axially on top of the flux pump header (161) under a non-contact structure, the flux pump rotor (162) being coaxial with the rotor shaft (210) and exposed to the outside of the top plate of the cryostat (140) (while passing through a rotary seal and a bearing) in such a way as to interlockingly rotate through a power transmission motor (164) and a rotary plate (165) and control the rotation of the permanent magnet (163).

4. The vertical axis wind turbine according to claim 2, wherein the cryostat (140) has a re-condensing cooler (170) and a re-condensing heat exchanger (180) disposed on one side of the inside thereof to perform re-condensation and re-liquefication of a gas refrigerant therein.

5. The vertical axis wind turbine according to claim 1, wherein the cryostat (140) is formed of a double jacket consisting of an inner case and an outer case, and a vacuum is formed in a space between the inner case and the outer case.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0037] FIG. 1 is an exemplary view showing a configuration of a vertical axis wind turbine equipped with a high-temperature superconducting generator having a batch impregnation cooling structure using a cryogen according to the present invention.

[0038] FIGS. 2 to 3 are exemplary views showing the high-temperature superconducting generator having the batch impregnation cooling structure according to the present invention.

[0039] FIG. 4 is an exemplary view showing a contact type exciter applied to the high-temperature superconducting generator according to an embodiment of the present invention.

[0040] FIG. 5 is an exemplary view showing a non-contact type exciter applied to the high-temperature superconducting generator according to another embodiment of the present invention.

[0041] FIG. 6 is an exemplary view showing a re-condensing cooler and a re-condensing heat exchanger with re-condensing and re-liquefying structures that are applied to the high-temperature superconducting generator according to the present invention.

EMBODIMENTS OF THE INVENTION

[0042] Hereinafter, embodiments of the present invention will be explained in detail with reference to the attached drawings.

[0043] Referring to FIGS. 1 to 6, a vertical axis wind turbine according to the present invention largely includes an axis type superconducting generator 100, a tower assembly 200, and a cryogenic cooling system 300.

[0044] The axis type superconducting generator 100 has a rotor core 110 vertically standing up thereon and a rotor 120 provided by locating a high-temperature superconducting field coil in a circumferential direction of the rotor core 110.

[0045] In this case, a stator 130 is provided by locating a superconducting armature coil in such a way as to be spaced apart from the rotor 120 by a given distance, so that upon rotation of the rotor 120, the stator 130 helps superconducting power generation, together with the rotor 120.

[0046] The rotor core 110, the rotor 120, and the stator 130, as an integral module, are accommodated in a cryostat 140, and the cryostat 140 has a refrigerant circulation inlet pipe 141 and a refrigerant circulation outlet pipe 142 disposed on one side and the other side thereof to perform batch impregnation cooling by means of a circulation refrigerant (introduced refrigerant is liquid and discharged refrigerant is gas) introduced from the cryogenic cooling system 300.

[0047] According to an embodiment of the present invention, the rotor core 110 and a rotor shaft 210 are connected to each other by means of a contact type exciter 150, and the contact type exciter 150 has a pair of current leads 151 conductive to the high-temperature superconducting field coil and a slip ring 152 and a brush 153 disposed on tops of the current leads 151 in such a way as to come into close contact with each other and be thus electrically connected to each other.

[0048] That is, if external power is supplied to the slip ring through the brush, the power supplied to the slip ring is conductive to the current leads rotating together with the high-temperature superconducting field coil of the rotor core 110, and the power supplied to the current leads is supplied to the high-temperature superconducting field coil of the rotor core 110, so that the rotor core 110 rotates inside the stator 130.

[0049] According to another embodiment of the present invention, further, the rotor core 110 and a rotor shaft 210 are connected to each other by means of a non-contact type exciter 160, and the non-contact type exciter 160 has a flux pump header 161 conductive to the high-temperature superconducting field coil.

[0050] In this case, further, a permanent magnet 163, which is coupled to a flux pump rotor 162, is located axially on top of the flux pump header 161 under a non-contact structure.

[0051] The flux pump rotor 162 is coaxial with the rotor shaft 210 and branched to the outside of a top plate of the cryostat 140 (while passing through a rotary seal and a bearing) in such a way as to interlockingly rotate through a power transmission motor 164 and a rotary plate 165 and control the rotation of the permanent magnet 163.

[0052] In this case, the cryostat 140 has a re-condensing cooler 170 and a re-condensing heat exchanger 180 disposed on one side of the inside thereof to perform re-condensation and re-liquefication of a gas refrigerant in the cryostat 140.

[0053] The cryostat 140 is formed of a double jacket consisting of an inner case and an outer case, and a vacuum is formed in a space between the inner case and the outer case.

[0054] Further, the tower assembly 200 has the rotor shaft 210 connected to top end periphery of the rotor core 110, and a top end portion of the rotor shaft 210 is branched to the outside of the top plate of the cryostat 140 (while passing through a rotary seal and a bearing) in such a way as to allow a shaft coupling 220 to be connected vertically to a main shaft 240 having vertical blades 230.

[0055] In this case, the main shaft 240 rotates inside a turbine tower 250 through support bearings 260.

[0056] Further, the cryogenic cooling system 300 has a cooling chamber 320 in which a circulation type cooling pump 310 is disposed, which is adapted to supply the liquid refrigerant to the cryostat 140, so that the vaporized gas refrigerant is collected.

[0057] In this case, a cryostat 330 and a helium compressor 340 are connected to one side and the other side of the cooling chamber 320 through respective supply lines.

[0058] According to the present invention, as shown in FIGS. 1 to 3, the vertical axis wind turbine is equipped with the superconducting generator, thereby solving various technical problems occurring in developing and operating the superconducting generator.

[0059] In building the vertical axis wind turbine according to the present invention, that is, the vertical blades located on the upper portion of the turbine tower are connected to the upper end of the main shaft as a main rotating shaft passing through the interior of the turbine tower.

[0060] In this case, the main shaft (the main rotating shaft) rotates, while being supported by the support bearings disposed inside the tower turbine, and particularly, the main shaft is directly connected to the rotor shaft of the superconducting generator located under the tower turbine, so that the rotary forces of the vertical blades, which are generated by wind, are immediately transferred to the superconducting generator.

[0061] Accordingly, the vertical axis wind generator according to the present invention is configured to allow the superconducting generator, the cryogenic cooling system, and a power conversion system to be all disposed in a structure located on the ground (under the tower turbine).

[0062] In this case, the superconducting generator located under the tower turbine is disposed vertically with respect to the rotor shaft and directly connected to the main shaft (the main rotating shaft) of the tower turbine, and accordingly, a radial-gap type superconducting generator and an axial-gap type superconducting generator may be structurally adopted.

[0063] Further, as shown in FIGS. 2 to 6, the superconducting generator in which the rotor or stator is disposed is configured to be located vertically inside the cryostat serving as the outer case, and the rotary shaft of the superconducting generator is withdrawn to a normal temperature portion through a special bearing support serving as a sealing structure attached to top of the cryostat and thus connected to the main rotating shaft of the wind turbine.

[0064] If a superconducting bearing having a liquefication temperature of the refrigerant used as an operating temperature is used, the superconducting bearing supports the rotor shaft in a non-contact manner to allow a frictional loss to be lower than that in a contact type bearing support structure.

[0065] Accordingly, the cryogenic cooling system of the present invention is located under the tower turbine, and the liquid refrigerant is supplied from the cryostat to allow the superconducting generator to be cooled to a target operating temperature. After the cooling, the vaporized gas refrigerant is collected back to the cooling system, re-cooled, and re-supplied, so that through such circulation, the superconducting generator becomes cooled.

[0066] In this case, the cryogenic liquid refrigerant used is determined according to the specifications of the superconducting coil, and helium, argon, neon, hydrogen, oxygen, nitrogen, and the like may be used as the cryogenic liquid refrigerant.

[0067] That is, under the batch impregnation cooling structure of the cryogenic liquid refrigerant, the superconducting generator is cooled by the cryogenic refrigerant being in a liquid state supplied initially from the outside.

[0068] Most of the liquid refrigerant introduced upon the initial cooling is vaporized, and the temperature of the superconducting generator becomes decreased for several hours until the superconducting generator being in a normal temperature has thermal equilibrium with the temperature of the liquid refrigerant. Simultaneously, the vaporized refrigerant is generated.

[0069] In this case, the liquid refrigerant is vaporized in proportion to the loss of the superconducting generator even at the temperature at the time point of the thermal equilibrium.

[0070] Further, the vaporized refrigerant generated upon the initial cooling and the normal operation is emitted to the outside or collected to a separate cryogenic cooling system, re-condensed, and re-supplied to the cryostat where the superconducting generator is located.

[0071] In this case, as shown in FIG. 6, the cryostat for the superconducting generator is configured to allow the cooler and the heat exchanger for refrigerant re-condensation to be connected directly to top thereof, thereby enhancing the cooling efficiency of the superconducting generator.

[0072] That is, the cooler and the heat exchanger enables the superconducting generator to be integral with the cooling system, thereby simplifying the cooling system in configuration and reducing the volume of the cooling system.

[0073] Accordingly, a single cooler or a plurality of coolers may be used in consideration of cooling amounts, and in some cases, the coolers may be located on the underside or side of the cryostat.

[0074] Further, a cryogenic freezer attached to the cryostat for the superconducting generator is controlled in temperature to allow the liquid refrigerant stored in the cryostat to be overcooled to enhance the cooling performance and to be cooled to a solid to improve the cooling performance and the thermal stability of the superconducting field coil.

[0075] While the present invention has been described with reference to the particular illustrative embodiments, it is not to be restricted by the embodiments but only by the appended claims. It is to be appreciated that those skilled in the art can change or modify the embodiments without departing from the scope and spirit of the present invention.

TABLE-US-00001 [Explanations of Reference Numerals] 00072 > 100 . . . Superconducting generator 110 . . . Rotor core 120 . . . Rotor 130 . . . Stator 140 . . . Cryostat 141 . . . Inlet pipe 142 . . . Outlet pipe 150 . . . Contact type exciter 151 . . . Current lead 152 . . . Slip ring 153 . . . Brush 160 . . . Non-contact type exciter 161 . . . Flux pump header 162 . . . Flux pump rotor 163 . . . Permanent magnet 164 . . . Motor 165 . . . Rotary plate 170 . . . Cooler 180 . . . Heat exchanger 200 . . . Tower assembly 210 . . . Rotor shaft 220 . . . Shaft coupling 230 . . . Vertical blade 240 . . . Main shaft 250 . . . Turbine tower 260 . . . Support bearing 300 . . . Cryogenic cooling system 310 . . . Cooling pump 320 . . . Cooling chamber 330 . . . Cryostat 340 . . . Helium compressor