Power generator and gas-turbine engine including the same

Abstract

To provide a gas-turbine engine including a power generator, in which the degree of freedom of an arrangement of the power generator is increased.SOLUTION: A power generator is used for a gas-turbine engine. The power generator includes: a stator including a stator core and a wire wound around the stator core; a rotor placed inside the stator; and a case that stores the stator and the rotor. The wire has a star-connected neutral point. The neutral point is placed outside the case.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to an electrical generator and a gas turbine engine including the same. [Background technology]

[0002] As disclosed in Patent Document 1, for example, a generator that generates electric power to be supplied to electric accessories provided in the engine is disposed in the internal space of a casing of the gas turbine engine. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent No. 7174169 Summary of the Invention [Problem to be solved by the invention]

[0004] A gas turbine engine includes a number of components, such as a compressor, a combustor, and a turbine, and the arrangement space for a generator is limited.

[0005] Therefore, one aspect of the present disclosure aims to increase the degree of freedom in the arrangement of a generator in a gas turbine engine equipped with a generator. [Means for solving the problem]

[0006] One aspect of the present disclosure is a generator for use in a gas turbine engine, comprising a stator including a stator core and an electric wire wound around the stator core, a rotor arranged inside the stator, and a case that houses the stator and the rotor, wherein the electric wire has a star-connected neutral point, and the neutral point is arranged outside the case. Effect of the Invention

[0007] According to one aspect of the present disclosure, in a gas turbine engine equipped with a generator, the degree of freedom in the arrangement of the generator can be increased. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram of a gas turbine engine according to an embodiment. [Diagram 2] FIG. 2 is a diagram showing the configuration of the generator of FIG. 1 and its surroundings. [Diagram 3] FIG. 3 is a diagram showing a configuration of a generator according to a first modified example and its periphery. [Figure 4] FIG. 4 is a schematic diagram of a gas turbine engine according to a second modified example. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the drawings. In this disclosure, unless otherwise specified, each term has the following meaning. "Axial direction" means the axial direction of the rotating shaft of the gas turbine engine. "Forward" means the upstream side of the flow direction of air inside the gas turbine engine. Also, "rear" means the downstream side of the flow direction. In other words, "forward" means the side of the axial direction where the fan is arranged. Also, "rear" means the side of the axial direction opposite to the side where the fan is arranged. Also, "radial direction" means the direction perpendicular to the axial direction. Also, "circumferential direction" means the direction around the rotation axis of the rotating shaft.

[0010] FIG. 1 is a schematic diagram of a gas turbine engine 1 (hereinafter also simply referred to as "engine 1") according to an embodiment. The engine 1 is, as an example, a gas turbine engine for an aircraft. However, the engine 1 is not limited to use in aircraft. As shown in FIG. 1, the engine 1 includes a generator 2.

[0011] Gas turbine engines have limited space inside the engine, which can make it difficult to place a generator in a desired location inside the engine, and smaller gas turbine engines have even more limited space inside the engine.

[0012] On the other hand, in the engine 1, the electric wire 29 of the generator 2 has a star-connected neutral point 29d, and the neutral point 29d is disposed outside the case 27 of the generator 2. Therefore, the engine 1 can increase the degree of freedom in arranging the generator 2 even when the space for arranging the generator 2 is limited.

[0013] The engine 1 is a two-shaft gas turbine engine, but is not limited thereto. The engine 1 includes a fan 3, a compressor 4, a combustor 5, a turbine 6, a rotating shaft 7 that mechanically connects the compressor 4 to the turbine 6, a casing 8 that houses the compressor 4, the combustor 5, and the turbine 6, and at least one electric accessory 9. The compressor 4 compresses air supplied from the outside of the engine 1 to the inside by the fan 3. The combustor 5 burns fuel to generate combustion gas. The turbine 6 is supplied with the combustion gas generated by the combustor 5. The rotating shaft 7 extends in the front-rear direction of the engine 1 and rotates around a predetermined rotation axis X (see FIG. 2). The rotating shaft 7 is rotatably supported by a plurality of bearings BR1 and BR2. The fan 3 is mechanically connected to the rotating shaft 7 and rotates together with the rotating shaft 7. The fan 3, the compressor 4, the combustor 5, and the turbine 6 are arranged in this order from the front to the rear.

[0014] The compressor 4 includes a low-pressure compressor 13 and a high-pressure compressor 14 disposed behind the low-pressure compressor 13. The low-pressure compressor 13 is an axial compressor. The high-pressure compressor 14 is a centrifugal compressor. The types of the low-pressure compressor 13 and the high-pressure compressor 14 are not limited thereto. The turbine 6 includes a low-pressure turbine 15 and a high-pressure turbine 16 disposed in front of the low-pressure turbine 15. The rotating shaft 7 includes a low-pressure shaft 11 connecting the low-pressure compressor 13 to the low-pressure turbine 15, and a high-pressure shaft 12 connecting the high-pressure compressor 14 to the high-pressure turbine 16. The high-pressure shaft 12 is a hollow cylinder extending in the front-rear direction. The low-pressure shaft 11 is inserted into the high-pressure shaft 12. The low-pressure turbine 15 is connected to the fan 3 via the low-pressure shaft 11.

[0015] The casing 8 is a cylindrical body extending in the axial direction of the rotation axis X. The casing 8 houses the fan 3, the compressor 4, the combustor 5, the turbine 6, and the rotating shaft 7. The casing 8 has an inner shell 80, an outer shell 81, and struts 82 and 83. The inner shell 80 houses the compressor 4, the combustor 5, and the turbine 6. The outer shell 81 is arranged concentrically with the inner shell 80 while being spaced radially outward from the inner shell 80. A cylindrical bypass path BP is formed between the inner shell 80 and the outer shell 81. A part of the air sucked into the inside of the engine 1 by the fan 3 flows through the bypass path BP and is discharged rearward. The electric accessory 9 is attached to the outer circumferential surface of the casing 8. The electric accessory 9 may be attached inside the casing 8. The electric accessory 9 is, for example, a power consuming device such as a fuel pump and a lubricating oil pump, but is not limited thereto.

[0016] The struts 82 extend in the radial direction and connect the inner shell 80 and the outer shell 81. The struts 82 are disposed rearward of the low-pressure compressor 13. Note that the struts 82 may be disposed between the low-pressure compressor 13 and the high-pressure compressor 14 in the axial direction.

[0017] The engine 1 further includes a cylindrical body 20 that connects the low-pressure compressor 13 and the high-pressure compressor 14 in the axial direction inside the inner shell 80. The outer diameter and the inner diameter of the cylindrical body 20 decrease from the front to the rear. The cylindrical body 20 defines a part of the compressed air flow path R from the low-pressure compressor 13 to the high-pressure compressor 14. The outer peripheral surface of the cylindrical body 20 faces the compressed air flow path R. The struts 83 extend in the radial direction and connect the cylindrical body 20 and the inner shell 80. The struts 83 are disposed behind the low-pressure compressor 13. The struts 83 may be disposed between the low-pressure compressor 13 and the high-pressure compressor 14 in the axial direction.

[0018] The generator 2 is driven by the rotational driving force of the rotating shaft 7 to generate electricity. The electric power generated by the generator 2 is supplied to the electric accessory 9 to drive the electric accessory 9. The generator 2 may have a starter function that rotates the rotating shaft 7 when the engine 1 is started. In this case, the generator 2 is a motor generator. The generator 2 is disposed inside the casing 8. The generator 2 is disposed inside the cylindrical body 20 and in front of the high-pressure compressor 14.

[0019] FIG. 2 is a diagram showing the configuration of the generator 2 in FIG. 1 and its surroundings. In FIG. 2, the inside of the generator 2 and the neutral point 29d of the electric wire 29 are shown. The generator 2 includes a rotating shaft 24, a rotor 25, a stator 26, a case 27, and a connector 31. The rotating shaft 24 and the rotor 25 are disposed inside the stator 26. The rotating shaft 24 extends in the axial direction and is supported so as to rotate around the rotation axis X. The rotor 25 is a cylinder having an internal space extending in the axial direction of the rotation axis X. The rotating shaft 24 is inserted into the internal space of the rotor 25. The rotor 25 is coupled to the rotating shaft 24 and rotates around the rotation axis X together with the rotating shaft 24. The rotor 25 is surrounded by the stator 26 in the circumferential direction of the rotation axis X. The rotor 25 includes a permanent magnet 30. That is, the generator 2 is of a permanent magnet type. The generator 2 is a three-phase AC type that generates three-phase AC power including a U-phase, a V-phase, and a W-phase.

[0020] The stator 26 includes at least one stator core 28 arranged around the rotation axis X, and an electric wire 29 wound around the stator core 28. The stator 26 includes a plurality of stator cores 28. The case 27 houses the stator 26 and the rotor 25. For example, the case 27 covers the stator 26 and the rotor 25 from the radial outside and both sides in the axial direction.

[0021] The electric wire 29 is a three-phase winding. The electric wire 29 has a plurality of winding portions 29a wound around the stator core 28. The plurality of winding portions 29a are coil portions including a U-phase winding portion, a V-phase winding portion, and a W-phase winding portion. The plurality of winding portions 29a are wound around the stator core 28. The electric wire 29 is wound around the stator core 28 via a sheet-shaped insulating member. As a result, the electric wire 29 and the stator core 28 are insulated from each other.

[0022] The electric wire 29 has a first lead-out portion 29b extending from one end of each of the plurality of winding portions 29a, and a second lead-out portion 29c extending from the other end of each of the plurality of winding portions 29a. The plurality of first lead-out portions 29b are star-connected, in other words, Y-connected. This allows the electric wire 29 to have a neutral point 29d that is an electrical neutral point. The plurality of second lead-out portions 29c are electrically connected to wiring 40, which will be described later, outside the case 27. A connector 31 is attached to the electric wire 29. The connector 31 is attached to the plurality of second lead-out portions 29c.

[0023] In the generator 2, a Y-connection state through the neutral point 29d is maintained at least when the engine 1 is running. In the generator 2, the neutral point 29d is disposed outside the case 27. In the generator 2, the first lead-out portion 29b and the second lead-out portion 29c are disposed outside the case 27 together with the neutral point 29d.

[0024] The neutral point 29d may be disposed outside the case 27 in a direction perpendicular to the rotation axis X of the rotor 25. The neutral point 29d may be disposed outside the case 27 in the axial direction in which the rotation axis X of the rotor 25 extends.

[0025] Neutral point 29d may be disposed away from case 27. As an example, neutral point 29d is disposed away from both ends of winding portion 29a and case 27 in the axial direction.

[0026] The neutral point 29d may be disposed forward of the combustor 5. The neutral point 29d may also be disposed in a region that is lower in temperature than the region where the case 27 of the engine 1 has the highest temperature when the engine 1 is running. As an example, the neutral point 29d is disposed in a region that is lower in temperature by 100° C. or less than the region where the case 27 of the engine 1 has the highest temperature when the engine 1 is running.

[0027] The engine 1 includes a wiring 40 that transmits electric power generated by the generator 2 to the electric accessory 9 through the second lead-out line portion 29c, and a connector 41 attached to the wiring 40. The connector 41 is connected to the connector 31. As a result, the wiring 40 is electrically connected to the second lead-out line portion 29c to which the connector 31 is attached. The connector 31 includes, for example, a heat-resistant resin member.

[0028] The neutral point 29d is attached to the connector 31. The connector 31 has, for example, an internal space. The neutral point 29d is accommodated in this internal space. The neutral point 29d is attached to the connector 31 in a state insulated from the second lead-out portion 29c. Note that the neutral point 29d does not have to be grounded.

[0029] The generator 2 includes, for example, a voltage sensor 32 that detects a phase voltage of any one of the three-phase AC power output from the electric wire 29, which is a three-phase winding. The voltage sensor 32 detects the voltage between any one of the first lead-out wire portions 29b of the electric wire 29 and a neutral point 29d as the phase voltage. The voltage sensor 32 is connected to a processing circuit 33 included in the engine 1. The processing circuit 33 is configured to receive a detection signal from the voltage sensor 32. For example, the processing circuit 33 calculates the rotation speed of the generator 2 based on the detection signal from the voltage sensor 32. In this way, according to the configuration that detects the phase voltage, the rotation speed of the generator 2 can be measured at a lower voltage than in the configuration that detects the line voltage. Therefore, it is possible to suppress the occurrence of dielectric breakdown when the voltage is detected by the voltage sensor 32.

[0030] The processing circuit 33 is, for example, a controller 333 including a processor 330, a system memory 331, and a storage memory 332. The controller 333 receives a detection signal from the voltage sensor 32. The storage memory 332 stores a control program executed by the processor 330. The processor 330 executes the control program read from the storage memory 332 to the system memory 331 to calculate the rotation speed.

[0031] As described above, by arranging the neutral point 29d of the electric wire 29 of the generator 2 outside the case 27, the neutral point 29d can be arranged in any space inside the engine 1. Furthermore, the space in the case 27 for accommodating the neutral point 29d is not required. This allows the case 27 to be made smaller. This allows the degree of freedom in arranging the generator 2 in the engine 1 to be increased.

[0032] Moreover, by arranging the first lead wire portion 29b and the second lead wire portion 29c outside the case 27, the case 27 can be further reduced in size.

[0033] If the neutral point 29d is located in a region that is lower in temperature than the region where the case 27 of the engine 1 has the highest temperature when the engine 1 is running, the options for usable insulating materials increase. That is, insulating materials with a low heat resistance temperature can be used.

[0034] (Modification) The following describes the modifications of the present disclosure, focusing on the differences from the embodiments. Fig. 3 is a diagram showing a generator 102 according to a first modification and the configuration of its periphery. As shown in Fig. 3, the neutral point 29d of the first modification is not attached to the connector 31 and is disposed apart from the case 27. That is, the neutral point 29d is disposed apart from both the connector 31 and the case 27. The neutral point 29d is disposed outside the case 27 in a direction perpendicular to the rotation axis X.

[0035] The neutral point 29d may be disposed outside the case 27 in the axial direction in which the rotation axis X extends. The neutral point 29d may also be attached to the case 27. The neutral point 29d may also be attached to the case 27 via a support member.

[0036] Fig. 4 is a schematic diagram of a gas turbine engine 101 according to a second modified example. As shown in Fig. 4, the connector 31 of the second modified example is attached to the cylindrical body 20. The neutral point 29d is attached to the inner circumferential surface of the cylindrical body 20 in a state where it is attached to the connector 31. The neutral point 29d may be attached to the cylindrical body 20 via a support member in a state where it is attached to the connector 31. Moreover, the neutral point 29d may be attached to the cylindrical body 20 separately from the connector 31.

[0037] In the above embodiment, the axis of rotation X coincides with the axis of rotation of the rotating shaft 7, but it does not have to coincide with the axis of rotation. The case 27 may be made of either a single member or multiple members. The "low temperature area" of the engine 1 may be, for example, an area in front of the case 27, but is not limited thereto. For example, by grasping in advance the temperature change of the case 27 and the periphery of the case 27 when the engine 1 is driven, it is possible to confirm which area of ​​the engine 1 can be selected as the "low temperature area" of the engine 1. The voltage sensor 32 may be used for purposes other than calculating the number of revolutions of the generator 2. The neutral point 29d may be attached to, for example, the outer surface of the connector 31. In this way, when the neutral point 29d is not accommodated in the connector 31, the connector 31 can be made smaller in size.

[0038] Furthermore, in the axial direction of the rotation axis X, the case 27 may cover at least a part of each of the stator 26 and the rotor 25 from both or one side in the axial direction. Furthermore, the case 27 may be open on both sides in the axial direction of the rotation axis X. In this case, the internal space of the case 27 refers to a space defined by the case 27 between one end and the other end of the case 27 in the axial direction of the rotation axis X.

[0039] (Disclosure items) Each of the following sections is a disclosure of a preferred embodiment. [Item 1] A generator for use with a gas turbine engine, comprising: A stator including a stator core and an electric wire wound around the stator core; A rotor disposed inside the stator; a case that houses the stator and the rotor, The electric wire has a star-connected neutral point, A generator, wherein the neutral point is disposed outside the case.

[0040] According to the above configuration, by disposing the neutral point outside the case, the case and the neutral point can be disposed in separate spaces. This increases the degree of freedom in disposing the generator in the gas turbine engine. As a result, even when the space for disposing the generator in the gas turbine engine is limited, it becomes easier to dispose the generator.

[0041] [Item 2] 2. The generator according to item 1, wherein the neutral point is disposed outside the case in a direction perpendicular to the rotation axis of the rotor.

[0042] According to the above configuration, even if the space for arranging the generator is insufficient in the axial direction along which the rotation axis of the rotor extends, it is possible to easily arrange the generator in the gas turbine engine. Also, the neutral point can be separated from the rotation axis of the rotor in the orthogonal direction. This makes it possible to suppress the vibration and heat of the rotor from being transmitted to the neutral point when the gas turbine engine is running.

[0043] [Item 3] 3. The generator according to item 1 or 2, wherein the neutral point is disposed outside the case in an axial direction in which a rotation axis of the rotor extends.

[0044] According to the above-mentioned configuration, even if the space for arranging the generator in the direction perpendicular to the rotation axis of the rotor is insufficient, it is possible to easily arrange the generator in the gas turbine engine. Furthermore, when the generator is arranged around the rotation axis of the gas turbine engine, by arranging the neutral point in front of the case, it is possible to prevent the vibration and heat of the rotor from reaching the neutral point when the gas turbine engine is running.

[0045] [Item 4] 4. The generator according to any one of items 1 to 3, wherein the neutral point is disposed away from the case.

[0046] According to the above-mentioned configuration, it is possible to prevent vibration and heat of the case from reaching the neutral point when the gas turbine engine is running, and it is also possible to improve the degree of freedom in layout of the generator in the gas turbine engine.

[0047] [Item 5] A connector attached to the wire, 5. The generator according to any one of items 1 to 4, wherein the neutral point is attached to the connector.

[0048] According to the above configuration, the neutral point can be easily positioned relative to the case by attaching the neutral point to the connector attached to the electric wire. In addition, for example, when the neutral point is accommodated in the internal space of the connector, the neutral point can be protected from the outside. In addition, for example, when the connector is fixed to a gas turbine engine, the neutral point can be easily positioned relative to the gas turbine engine.

[0049] [Item 6] 6. The generator according to any one of items 1 to 5, wherein the rotor includes a permanent magnet.

[0050] According to the above configuration, the generator can be configured as a permanent magnet generator, which allows the generator to be made smaller than an induction generator or the like.

[0051] [Item 7] The electric wire is a three-phase winding, 7. The generator according to any one of items 1 to 6, further comprising a voltage sensor that detects a phase voltage of any one of the three-phase AC power phases output from the three-phase winding.

[0052] According to the above configuration, the occurrence of dielectric breakdown when detecting a voltage with a voltage sensor can be suppressed compared to when the line voltage is detected with a voltage sensor. Therefore, for example, the voltage sensor can be used to measure the rotation speed of a generator at a low voltage.

[0053] [Item 8] A compressor; a combustor for generating combustion gas; a turbine to which combustion gas is supplied from the combustor; a rotating shaft mechanically connecting the compressor to the turbine; a casing that houses at least the compressor and the combustor; 8. A gas turbine engine comprising: the generator according to any one of items 1 to 7, the generator being disposed in an internal space between the compressor and the rotating shaft and mechanically connected to the rotating shaft.

[0054] According to the above configuration, even when the space for arranging the generator is restricted by multiple components of the gas turbine engine, the generator can be easily arranged.

[0055] [Item 9] 9. The gas turbine engine of claim 8, wherein the neutral point is located forward of the combustor.

[0056] According to the above configuration, when the gas turbine engine is running, the heat of the combustor can be prevented from reaching the neutral point.

[0057] [Item 10] 10. The gas turbine engine according to claim 8 or 9, wherein the neutral point is disposed forward of the case.

[0058] According to the above configuration, even if the space for arranging the generator in the radial direction of the rotating shaft is insufficient in the gas turbine engine, it is easy to arrange the generator. Also, by arranging the neutral point in front of the case, it is possible to prevent vibration and heat of the case from reaching the neutral point when the gas turbine engine is running.

[0059] [Item 11] 11. The gas turbine engine according to any one of items 8 to 10, wherein the neutral point is disposed away from the case in a radial direction of the rotating shaft.

[0060] According to the above configuration, even if the space for arranging the generator in the axial direction of the rotating shaft is insufficient in the gas turbine engine, the generator can be easily arranged. Also, by separating the neutral point from the case in the radial direction of the rotating shaft, it is possible to suppress the transmission of heat and vibration from the case or the rotating shaft to the neutral point when the gas turbine engine is running.

[0061] [Item 12] 12. The gas turbine engine according to any one of items 8 to 11, wherein the neutral point is disposed in a region that is lower in temperature than a region in which the case has a maximum temperature.

[0062] According to the above configuration, by locating the neutral point in an area that is lower in temperature than the area where the engine case has the highest temperature, it is possible to prevent the influence of heat from the gas turbine engine during operation on the neutral point. In addition, since the influence of heat on the neutral point is suppressed, for example, materials other than those having high heat resistance can be used as the covering material for covering the electric wire. This improves the degree of freedom in selecting or designing the covering material. [Explanation of symbols]

[0063] X rotation axis 1, 101 Gas Turbine Engine 2, 102 Generator 3 Fan 4. Compressor 5. Combustor 6. Turbine 7 Rotation Axis 8 Casing 25 Rotor 26 Stator 27 cases 29 Electric wire 29d Neutral point 30 Permanent Magnets 31 Connector

Claims

1. A generator for use with a gas turbine engine, comprising: A stator including a stator core and an electric wire wound around the stator core; A rotor disposed inside the stator; a case that houses the stator and the rotor, The electric wire has a star-connected neutral point, A generator, wherein the neutral point is disposed outside the case.

2. The generator according to claim 1 , wherein the neutral point is disposed outside the case in a direction perpendicular to the rotation axis of the rotor.

3. The generator according to claim 1 , wherein the neutral point is disposed outside the case in an axial direction in which a rotation axis of the rotor extends.

4. The generator of claim 1 , wherein the neutral point is located away from the case.

5. A connector attached to the wire, The generator according to any one of claims 1 to 4, wherein the neutral point is attached to the connector.

6. The generator according to any one of claims 1 to 4, wherein the rotor includes a permanent magnet.

7. The electric wire is a three-phase winding, The generator according to any one of claims 1 to 4, further comprising a voltage sensor that detects a phase voltage of any one of the three-phase AC power phases output from the three-phase winding.

8. A compressor; A combustor for generating combustion gas; a turbine to which combustion gas is supplied from the combustor; a rotating shaft mechanically connecting the compressor to the turbine; a casing that houses at least the compressor and the combustor; 2. The gas turbine engine according to claim 1, further comprising: a generator disposed in an interior space between the compressor and the rotating shaft and mechanically connected to the rotating shaft.

9. The gas turbine engine of claim 8 , wherein the neutral point is located forward of the combustor.

10. 10. The gas turbine engine according to claim 8, wherein the neutral point is disposed forward of the case.

11. 10. The gas turbine engine according to claim 8, wherein the neutral point is disposed away from the case in a radial direction of the rotating shaft.

12. 10. The gas turbine engine according to claim 8, wherein the neutral point is disposed in a region that is lower in temperature than a region in which the case has a maximum temperature.

Images