rotating electrical machines

Abstract

To provide a rotary electric machine which can inhibit an oil from entering a gap between a stator and a rotor and cool the stator and the rotor.SOLUTION: A power generator 1 includes: a rotor 20; a stator 30 which is arranged spaced apart from an outer peripheral surface of the rotor 20 by a predetermined distance in a radial direction; a housing 40 which houses the rotor 20 and the stator 30; and a gas inflow passage 60 which supplies a gas to a gap between the rotor 20 and the stator 30.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a rotating electric machine. [Background technology]

[0002] In recent years, research and development has been conducted to contribute to energy efficiency, ensuring that more people have access to affordable, reliable, sustainable and advanced energy.

[0003] In rotating electrical machines such as motors and generators, it is necessary to suppress a decrease in output power in order to improve energy efficiency. Because output power decreases when the rotating electrical machine becomes hot, it is necessary to provide a cooling mechanism in the rotating electrical machine to suppress the decrease in output power. For example, Patent Document 1 discloses that oil is supplied to the inside of the motor case to cool the internal parts such as the stator with oil to prevent the motor from becoming too hot. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2019-050707 Summary of the Invention [Problem to be solved by the invention]

[0005] Incidentally, if the gap between the rotor and stator (the so-called air gap) is large, the output of the rotating electrical machine decreases, so it is preferable to keep the gap small to prevent this output decrease. However, if the gap is small, if oil enters the gap, friction will occur during rotor rotation, resulting in a decrease in output. It is also known that if the gap is small, three-dimensional vortices will occur in the gap when the rotor rotates, generating heat.

[0006] The present invention provides a rotating electric machine that can prevent oil from entering a gap between a rotor and a stator and can cool the rotor and the stator. [Means for solving the problem]

[0007] The present invention The first aspect of teeth, A rotating electric machine, A rotor, a stator disposed at a predetermined distance in the radial direction from the outer circumferential surface of the rotor; a housing that accommodates the rotor and the stator; an inlet passage for supplying gas to the gap between the rotor and the stator; a bearing that rotatably supports a rotor shaft of the rotor at one end side and the other end side of the axial direction relative to the housing; Equipped with 、 The bearing is supplied with oil, The gas supplied to the gap flows into the space in which the bearing is provided, a turbine coupling portion provided on the one end side of the rotor shaft is coaxially coupled to a turbine of a gas turbine engine, and the rotor shaft rotates due to rotation of the turbine; The gap and the space at the one end where the bearing is provided are communicated with each other through two paths. do. A second aspect of the present invention is A rotating electric machine, A rotor, a stator disposed at a predetermined distance in the radial direction from the outer circumferential surface of the rotor; a housing that accommodates the rotor and the stator; an inlet passage for supplying gas to the gap between the rotor and the stator; The inlet channel is a first inlet passage for supplying the gas to the gap from one end side and the other end side of the gap in the axial direction; a second inlet passage provided in the rotor or the stator so as to extend radially and communicate with a central portion between the one end and the other end of the gap in the axial direction, The rotor or the stator has an outflow passage extending in a radial direction, the outflow passage communicating with the gap and discharging the gas supplied to the gap to the outside, The outflow channel is provided in the axial direction between the one end and the central portion and / or between the other end and the central portion. [Effects of the Invention]

[0008] According to the present invention, it is possible to prevent oil from entering the gap between the rotor and the stator, and to cool the rotor and the stator. [Brief explanation of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view of a generator 1 according to a first embodiment. [Figure 2] FIG. 2 is an enlarged cross-sectional view of the vicinity of a bearing 52. [Figure 3]10 is a schematic diagram showing the flow of compressed gas supplied to a gap 63 between a rotor 20 and a stator 30 in a generator 1 of a second embodiment. FIG. [Figure 4] 10 is a schematic diagram showing the flow of compressed gas supplied to a gap 63 in a generator 1 of a third embodiment. FIG. [Figure 5] FIG. 10 is a schematic diagram showing the flow of compressed gas supplied to a gap 63 in a generator 1 of a fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, embodiments of a rotating electric machine according to the present invention will be described with reference to the drawings.

[0011] First Embodiment 1, a generator 1, which is an example of a rotating electric machine of the present invention, includes a rotor shaft 10, a rotor 20 that rotates integrally with the rotor shaft 10, a stator 30 that is disposed at a predetermined radial distance from the outer circumferential surface of the rotor 20, a housing 40 that accommodates the rotor 20 and the stator 30, and a pair of bearings 51, 52 that are disposed on one end and the other end in the axial direction across the rotor 20 and support the rotor shaft 10 rotatably relative to the housing 40. A permanent magnet (not shown) is attached to the rotor 20, and the stator 30 has a stator core 31 around which a coil 32 is wound.

[0012] A gas turbine engine 2, which is an example of an internal combustion engine, is connected to the generator 1. Although not shown, the gas turbine engine 2 burns air compressed by a compressor and fuel (jet fuel, etc.) in a combustion chamber, and rotates a turbine with the exhaust flow generated when the high-temperature, high-pressure gas is discharged. The turbine is coaxially connected to a turbine connector 11 provided on a rotor shaft 10 of the generator 1, and the rotor shaft 10 rotates due to the rotation of the turbine. In other words, the generator 1 and the gas turbine engine 2 constitute a power generation system, and the generator 1 generates power using the output of the gas turbine engine 2. Note that, hereinafter, the side of the generator 1 facing the gas turbine engine 2 in the axial direction will also be referred to as a first end, and the opposite side will also be referred to as a second end.

[0013] The housing 40 has a hollow main body 41 and a flange 42 provided at an end portion on the first end side of the main body 41. The main body 41 has a substantially cylindrical shape and has an internal storage space S1 that stores components such as the rotor 20, the stator 30, and bearings 51 and 52. The flange 42 is fixed to the gas turbine engine 2.

[0014] A hole through which the rotor shaft 10 can be inserted is formed in the main body 41 and the flange 42, and bearing holders 43, 44 are disposed in the hole. The bearing holders 43, 44 are provided at the first and second ends of the housing 40, respectively, and hold the bearings 51, 52. That is, the bearing holders 43, 44 support the bearings 51, 52, which rotatably support the rotor shaft 10, relative to the housing 40. The bearing holders 43, 44 are also provided with oil flow paths and oil jet nozzles (not shown) that supply oil to the bearings 51, 52, and the bearings 51, 52 are lubricated by oil.

[0015] The generator 1 is provided with a gas inlet passage 60 that supplies compressed gas to the accommodation space S1 of the housing 40. As will be described in detail later, the compressed gas supplied to the accommodation space S1 is effectively used for cooling the rotor 20 and the stator 30. The thick arrows shown in Fig. 1 indicate the flow of compressed gas.

[0016] The compressed gas is, for example, a portion of air compressed by a compressor of the gas turbine engine 2, and the gas inlet passage 60 communicates with a compressed gas outlet passage of the gas turbine engine 2, and the compressed gas is supplied to the gas inlet passage 60. However, the compressed gas is not limited to gas supplied from the gas turbine engine 2, and may be compressed gas generated by a compressor or the like provided separately from the gas turbine engine 2. Note that, because the air compressed by the compressor is hot, before being supplied to the gas inlet passage 60, the compressed air may be cooled, for example, by a heat exchanger (not shown) or by a water jacket (not shown) provided in the housing 40.

[0017] The gas inlet passage 60 has a housing-side inlet passage 61 provided in the main body portion 41 and the flange portion 42 of the housing 40, and a stator-side inlet passage 62 provided in the stator 30 and communicating with the housing-side inlet passage 61. The stator-side inlet passage 62 communicates with a gap 63 (a so-called air gap) between the rotor 20 and the stator 30, and the compressed gas is supplied to the gap 63.

[0018] More specifically, the stator-side inlet passage 62 extends radially and communicates with a central portion between a first end portion 63a and a second end portion 63b of the gap 63 in the axial direction of the generator 1. The compressed gas supplied to the axial central portion of the gap 63 flows toward the first end portion 63a and the second end portion 63b and is discharged to the accommodation space S1 outside the gap 63. Note that a plurality of stator-side inlet passages 62 may be provided in the circumferential direction of the stator 30 in order to supply compressed gas to the gap 63 more uniformly.

[0019] The accommodation space S1 communicates with bearing arrangement spaces S2 and S3 (i.e., the gaps between the bearing holders 43 and 44 and the rotor shaft 10) in which the bearings 51 and 52 are arranged. Since the accommodation space S1 into which the compressed gas is introduced has a higher pressure than the bearing arrangement spaces S2 and S3, the compressed gas also flows into the bearing arrangement spaces S2 and S3.

[0020] 2 is a partially enlarged view of the vicinity of the bearing arrangement space S3 in which the bearing 52 is disposed in FIG. 1, with the flow of compressed gas indicated by a solid line and the flow of oil indicated by a dashed line. Note that although the compressed gas may be depressurized when it is discharged into the accommodation space S1 from the gap 63, for simplicity's sake, hereinafter the compressed gas discharged into the accommodation space S1 and the bearing arrangement spaces S2 and S3 will also be referred to as compressed gas. Furthermore, the bearing arrangement space S2 in which the bearing 51 is disposed has a similar configuration, and therefore a description thereof will be omitted.

[0021] As described above, oil for lubrication is supplied to the bearing 52, and the oil flows in the bearing arrangement space S3. The bearing holder 44 is provided with an oil discharge path 45 on the first end side (i.e., the rotor 20 side) of the bearing 52, so the oil flowing in the bearing arrangement space S3 is discharged from the oil discharge path 45 to the outside of the bearing arrangement space S3.

[0022] However, there is a risk that some of the oil flowing through the bearing arrangement space S3 will flow into the accommodation space S1. If the oil flows into the accommodation space S1 and enters the gap 63, friction will occur due to the oil present in the gap 63 when the rotor 20 rotates, resulting in a decrease in output.

[0023] In this embodiment, the compressed gas flowing within the accommodation space S1 flows toward the bearing arrangement space S3, so the oil supplied to the bearing 52 does not enter the accommodation space S1, thereby preventing the occurrence of friction as described above. Therefore, the rotor 20 can rotate under high load and / or high rotation speed conditions. Furthermore, the bearing 52 is cooled by the compressed gas, preventing damage to the bearing 52, which can become hot due to high-speed rotation. The oil flowing through the oil discharge path 45 is discharged to the outside from the oil discharge port 46 together with the compressed gas.

[0024] As described above, supplying compressed gas to the gap 63 between the rotor 20 and the stator 30 can prevent oil supplied to the bearings 51, 52 from entering the accommodation space S1 outside the bearing arrangement spaces S2, S3. Furthermore, because the pressure inside the gap 63 is increased by the compressed gas, even if oil enters the accommodation space S1 and flows toward the first end 63a and the second end 63b, the pressure difference between the inside and outside of the gap 63 can prevent the oil from entering the gap 63. Therefore, when the rotor 20 rotates, friction caused by the oil present in the gap 63 can be prevented, which would otherwise cause a decrease in output.

[0025] Furthermore, supplying compressed gas to gap 63 can cool rotor 20 and stator 30. In particular, if gap 63 is very small, a three-dimensional vortex may be generated during rotation of rotor 20, generating heat. However, since compressed gas is supplied as a refrigerant to gap 63, the generation of heat due to the three-dimensional vortex can be suppressed. Therefore, gap 63 can be made smaller, and the output of generator 1 can be improved.

[0026] Furthermore, the compressed gas is supplied from the axial center of the gap 63 so as to flow toward the first end 63a and the second end 63b. For example, if compressed gas is supplied to the gap 63 from the first end 63a and discharged from the second end 63b, the rotor 20 and the stator 30 can be cooled near the first end 63a, but the temperature of the compressed gas gradually increases, and it may not be possible to cool the rotor 20 and the stator 30 near the second end 63b. In this embodiment, the compressed gas is supplied from the axial center of the gap 63, so that the rotor 20 and the stator 30 can be cooled over the entire axial area.

[0027] The compressed gas that flows into the bearing arrangement space S2 in which the bearing 51 is arranged flows through the vent hole 64b formed in the flange portion 42 and the first end-side flow path 64, and flows to the turbine coupling part 11 that is coupled to the turbine of the gas turbine engine 2. The outlet 64a of the first end-side flow path 64 is connected to the bearing arrangement space S2. With this configuration, the compressed gas flows toward the bearing arrangement space S2, thereby preventing oil supplied to the bearing 51 from flowing to the gas turbine engine 2 via the turbine coupling part 11. This makes it possible to prevent friction caused by the oil from occurring and reducing the output of the gas turbine engine 2.

[0028] Second Embodiment Next, a generator 1 according to a second embodiment will be described with reference to Fig. 3. Members common to those in the first embodiment will be given the same reference numerals and descriptions thereof will be omitted.

[0029] In the second embodiment, a gas inlet passage 60 that supplies gas to the accommodation space S1 is provided in the rotor shaft 10 and the rotor 20. Specifically, the gas inlet passage 60 is provided in the rotor shaft 10 and the rotor 20 instead of the stator-side inlet passage 62, and has a rotor-side inlet passage 65 that communicates with a gap 63 between the rotor 20 and the stator 30. Although not shown in the figure, the rotor-side inlet passage 65 communicates with the housing-side inlet passage 61, and the compressed gas is supplied to the gap 63 through the rotor-side inlet passage 65.

[0030] Even with this configuration, compressed gas can be supplied to the gap 63, so similar to the first embodiment, it is possible to prevent oil from entering the gap 63 and to cool the rotor 20 and the stator 30.

[0031] Third Embodiment Next, a generator 1 according to a third embodiment will be described with reference to Fig. 4. Members common to the above-described embodiments will be given the same reference numerals and descriptions thereof will be omitted.

[0032] In the third embodiment, the rotor 20 and the rotor shaft 10 are provided with an outlet passage 66 that discharges the compressed gas supplied from the stator-side inlet passage 62 to the gap 63 to the outside. Specifically, the outlet passage 66 is provided between the first end portion 63a and the second end portion 63b. With this configuration, the compressed gas supplied from the stator-side inlet passage 62 can be discharged to the outside before it is heated and loses its cooling function.

[0033] The outflow passage 66 may be provided in the stator 30. In the example shown in Fig. 4, two outflow passages 66 communicating with the gap 63 are provided, but the number is not limited thereto and may be one, or three or more.

[0034] In addition to the supply from the stator-side inlet channel 62, the compressed gas may be supplied to the gap 63 from the first end 63a and the second end 63b. For example, in the example shown in FIG. 4 , the gas inlet channel 60 has a first end inlet channel 67a provided in the accommodation space S1 and communicating with the first end 63a, and a second end inlet channel 67b provided in the accommodation space S1 and communicating with the second end 63b. In this case, by providing two outlet channels 66, 66 between the first end inlet channel 67a and the stator-side inlet channel 62 and between the second end inlet channel 67b and the stator-side inlet channel 62, respectively, the compressed gas can be discharged to the outside before it becomes heated and loses its cooling function.

[0035] Fourth Embodiment Next, a generator 1 according to a fourth embodiment will be described with reference to Fig. 5. Members common to the above-described embodiments will be given the same reference numerals and descriptions thereof will be omitted.

[0036] In the fourth embodiment, the gas inlet passage 60 has a first end side inlet passage 67a and a second end side inlet passage 67b, similar to the third embodiment. Note that in the fourth embodiment, the gas inlet passage 60 is not provided in the rotor 20 or the stator 30.

[0037] The generator 1 of the fourth embodiment includes a switching unit 70 that can alternately switch between supplying compressed gas from the first-end inlet channel 67a and supplying compressed gas from the second-end inlet channel 67b. The switching unit 70 includes, for example, a three-way valve that can switch so that compressed gas flowing through the housing-side inlet channel 61 flows to either the first-end inlet channel 67a or the second-end inlet channel 67b, and flow path switching control is performed by a controller or the like.

[0038] Specifically, first, the switching unit 70 opens and closes the three-way valve so that the compressed gas flows into the first-end inlet channel 67a, and supplies the compressed gas from the first-end inlet channel 67a to the gap 63. After a predetermined time has elapsed, the switching unit 70 opens and closes the three-way valve so that the compressed gas flows into the second-end inlet channel 67b, and supplies the compressed gas from the second-end inlet channel 67b to the gap 63. The switching unit 70 repeats the operation of alternately switching the flow of compressed gas in the gap 63 at predetermined time intervals. This switching operation allows the rotor 20 and the stator 30 to be cooled uniformly in the axial direction.

[0039] Although the embodiments of the present invention have been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such embodiments. It is clear that those skilled in the art can conceive of various modifications and alterations within the scope of the claims, and it is understood that these also fall within the technical scope of the present invention. Furthermore, the components of the above embodiments may be combined in any manner without departing from the spirit of the invention.

[0040] For example, in each of the above-described embodiments, the generator 1 is connected to the gas turbine engine 2, but this is not limiting, and the generator 1 does not have to be connected to the gas turbine engine 2.

[0041] In the above-described embodiments, the generator 1 is used as an example of the rotating electric machine of the present invention, but the present invention is not limited to this. The rotating electric machine of the present invention may be a motor serving as a drive source.

[0042] In the above-described embodiments, compressed gas is supplied, but this is not limiting. As long as it is possible to prevent oil from entering the gap 63 and to cool the rotor 20 and the stator 30, it is also possible to supply uncompressed gas.

[0043] In the above-described embodiment, the stator-side inlet passage 62 and the rotor-side inlet passage 65 communicate with the central portion between the first end portion 63a and the second end portion 63b of the gap 63 in the axial direction, but they do not have to be provided in the central portion. Also, a plurality of stator-side inlet passages 62 and a plurality of rotor-side inlet passages 65 may be provided.

[0044] This specification describes at least the following items. Note that the components in parentheses correspond to those in the above-described embodiment, but are not limited to these.

[0045] (1) a rotor (rotor 20); a stator (stator 30) disposed at a predetermined radial distance from the outer circumferential surface of the rotor; a housing (housing 40) that accommodates the rotor and the stator; a gas inlet passage (gas inlet passage 60) for supplying gas to the gap between the rotor and the stator;

[0046] According to (1), gas is supplied to the gap between the rotor and the stator, so that oil can be prevented from entering the gap, and the rotor and the stator can be cooled.

[0047] (2) The rotating electric machine according to (1), The gas supplied to the inlet passage is a compressed gas.

[0048] According to (2), the gap between the rotor and the stator is pressurized by the compressed gas, so that oil can be further prevented from entering the gap.

[0049] (3) The rotating electric machine according to (1) or (2), The rotor shaft (rotor shaft 10) of the rotor is further provided with bearings (bearings 51, 52) that support the rotor shaft with respect to the housing, The bearing is supplied with oil, The gas supplied to the gap flows into the spaces in which the bearings are provided (bearing arrangement spaces S2, S3).

[0050] According to (3), the gas supplied to the gap between the rotor and the stator flows into the space where the bearing is provided, so that the oil supplied to the bearing can be prevented from entering the gap.

[0051] (4) A rotating electric machine according to any one of (1) to (3), A rotating electric machine, wherein the inlet passage is provided in the rotor or the stator and communicates between one end (first end 63a) and the other end (second end 63b) of the gap in the axial direction.

[0052] According to (4), the inflow passage communicates between one end and the other end in the axial direction of the gap between the rotor and the stator, so that the rotor and the stator can be cooled over the entire axial area.

[0053] (5) The rotating electric machine according to (4), The inlet passage communicates with a central portion of the gap between the one end and the other end.

[0054] According to (5), the inlet passage is connected to the center between one end and the other end of the gap between the rotor and the stator, so that the rotor and the stator can be cooled uniformly on both the one end side and the other end side.

[0055] (6) A rotating electric machine according to (4) or (5), The rotor or the stator is provided with at least one outlet path for discharging the gas supplied to the gap to the outside, The at least one outlet passage is provided between the one end and the other end of the gap.

[0056] According to (6), at least one outlet passage is provided between one end and the other end of the gap between the rotor and the stator, so that the compressed gas supplied to the gap can be discharged to the outside before the temperature of the compressed gas increases and it loses its cooling function, thereby sufficiently cooling the rotor and the stator.

[0057] (7) A rotating electric machine according to any one of (1) to (5), the inlet passage includes at least a first inlet passage (a first end side inlet passage 67a and a second end side inlet passage 67b) and a second inlet passage (a stator side inlet passage 62) that supply the gas to the gap, The rotor or the stator is provided with an outflow path (outflow path 66) for discharging the gas supplied to the gap to the outside, The outlet passage is provided between the first inlet passage and the second inlet passage in the axial direction.

[0058] According to (7), since the outlet passage is provided between the first inlet passage and the second inlet passage in the axial direction, the compressed gas supplied from the first inlet passage and the second inlet passage can be discharged to the outside before the temperature of the compressed gas increases and the compressed gas loses its cooling function, thereby sufficiently cooling the rotor and the stator.

[0059] (8) A rotating electric machine according to any one of (1) to (3), The inflow passage has a one-end side inflow passage (first-end side inflow passage 67a) that communicates with one end of the gap in the axial direction, and an other-end side inflow passage (second-end side inflow passage 67b) that communicates with the other end of the gap in the axial direction. The rotating electric machine further includes a switching unit (switching unit 70) capable of switching between supplying the gas from the one end side inlet channel and supplying the gas from the other end side inlet channel.

[0060] According to (8), the switching unit switches between supplying gas from the inlet channel on one end side and supplying gas from the inlet channel on the other end side, so that the rotor and the stator can be cooled uniformly in the axial direction. [Explanation of symbols]

[0061] 1. Generator 10 rotor shaft 20 rotors 30 Stator 40 Housing 60 Gas inlet (inlet) 62 Stator side inlet passage (second inlet passage) 63a First end side end (one end) 63b Second end side end (other end) 66 Outflow channel 67a First end side inflow path (first inflow path, one end side inflow path) 67b Second end side inflow path (first inflow path, other end side inflow path) 70 Switching section

Claims

1. A rotor, a stator disposed at a predetermined distance in the radial direction from the outer circumferential surface of the rotor; a housing that accommodates the rotor and the stator; an inlet passage for supplying gas to the gap between the rotor and the stator; a bearing that rotatably supports a rotor shaft of the rotor at one end side and the other end side of the axial direction relative to the housing, The bearing is supplied with oil, The gas supplied to the gap flows into the space in which the bearing is provided, a turbine coupling portion provided on the one end side of the rotor shaft is coaxially coupled to a turbine of a gas turbine engine, and the rotor shaft rotates due to rotation of the turbine; The gap and the space at the one end where the bearing is provided are in communication with each other through two paths.

2. 2. The rotating electric machine according to claim 1, The gas supplied to the inlet passage is a compressed gas.

3. 3. The rotating electric machine according to claim 1, The inlet passage is provided in the rotor or the stator and communicates between one end and the other end of the gap in the axial direction.

4. 4. The rotating electric machine according to claim 3, The inlet passage communicates with a central portion of the gap between the one end and the other end.

5. 5. The rotating electric machine according to claim 3, the rotor or the stator is provided with at least one outlet path for discharging the gas supplied to the gap to the outside, The at least one outlet passage is provided between the one end and the other end of the gap.

6. 5. A rotating electric machine according to claim 1, the inlet channel includes at least a first inlet channel and a second inlet channel that supply the gas to the gap, an outlet path for discharging the gas supplied to the gap to the outside is provided in the rotor or the stator; The outlet passage is provided between the first inlet passage and the second inlet passage in the axial direction.

7. 3. The rotating electric machine according to claim 1, The inflow passage has a one-end inflow passage communicating with one end of the gap in the axial direction, and an other-end inflow passage communicating with the other end of the gap in the axial direction. The rotating electric machine further includes a switching unit that can switch between supplying the gas from the one end inlet channel and supplying the gas from the other end inlet channel.

8. A rotor, a stator disposed at a predetermined distance in the radial direction from the outer circumferential surface of the rotor; a housing that accommodates the rotor and the stator; an inlet passage for supplying gas to the gap between the rotor and the stator; The inlet channel is a first inlet passage for supplying the gas to the gap from one end side and the other end side of the gap in the axial direction; a second inlet passage provided in the rotor or the stator so as to extend radially and communicate with a central portion between the one end and the other end of the gap in the axial direction, The rotor or the stator has an outflow passage extending in a radial direction, the outflow passage communicating with the gap and discharging the gas supplied to the gap to the outside, The rotating electric machine, wherein the outflow passage is provided in the axial direction between the one end and the central portion and / or between the other end and the central portion.

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