Bearing device for power generators, power generation device, and turbine power generation system

Abstract

The present invention comprises: a bearing that is configured to rotatably support a rotor of a power generator; a bearing casing that accommodates the bearing; a bearing ring that is provided between the bearing casing and the bearing; an insulation member that is provided between an outer peripheral surface of the bearing ring and an inner surface of the bearing casing; a first pad that is provided to the inner peripheral surface side of the bearing ring and that is disposed so as to face an outer peripheral surface of the bearing with a gap therebetween; and a liner that is sandwiched between the first pad and the inner peripheral surface of the bearing ring.

Description

Generator bearing device, power generating device, and turbine power generating system

[0001] The present disclosure relates to a bearing device for a generator, a power generation device, and a turbine power generation system.

[0002] Patent Document 1 discloses a bearing device for a rotary machine that suppresses rotational loss with a simple configuration. This bearing device includes a casing provided around a rotating shaft, a bearing pad provided facing the lower side of the rotating shaft in the vertical direction and swingable relative to the casing, which supports the rotating shaft by forming a lubricating film between itself and the rotating shaft, and a fixed pad provided facing the upper side of the rotating shaft in the vertical direction and fixed to the casing, which covers the rotating shaft by forming a lubricating film between itself and the rotating shaft.

[0003] Japanese Patent Application Laid-Open No. 2019-138455

[0004] Incidentally, when the bearing device for a rotary machine is a generator bearing device that rotatably supports the rotor of a generator, if a closed circuit is formed between the rotor and the stator side casing or the like via the bearing device, an axial current will flow in the closed circuit due to the potential difference between both ends of the rotor shaft, and therefore, in order to suppress the axial current, it is necessary to provide an insulating member in the bearing device on at least one side of the rotor.

[0005] When a bearing device for a generator including such an insulating member is adopted, the bearing device includes an annular bearing configured to rotatably support the rotor of the generator, a bearing casing that houses the bearing, a bearing ring provided between the bearing casing and the bearing, and an insulating member provided between the outer circumferential surface of the bearing ring and the inner surface of the casing, it is necessary to set an appropriate gap (back gap) between the bearing ring and the bearing from the standpoint of preventing oil leakage, suppressing whirling of the rotor, etc. In this regard, the bearing device described in Patent Document 1 is not a bearing device for a generator, and does not disclose a configuration for easily adjusting the gap between the bearing ring and the bearing in a bearing device for a generator that includes an insulating member to suppress axial current.

[0006] In view of the above circumstances, at least one embodiment of the present disclosure aims to provide a bearing device for a generator, a power generation device, and a turbine power generation system that allows for easy adjustment of the gap between the bearing ring and the bearing for a bearing device for a generator that includes an insulating member for suppressing axial current.

[0007] In order to achieve the above object, a bearing device for a generator according to at least one embodiment of the present disclosure comprises: a bearing configured to rotatably support a rotor of a generator; a bearing casing that houses the bearing; a bearing ring provided between the bearing casing and the bearing; an insulating member provided between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing; a first pad provided on the inner peripheral surface of the bearing ring and arranged to face the outer peripheral surface of the bearing via a gap; and a liner sandwiched between the inner peripheral surface of the bearing ring and the first pad.

[0008] According to at least one embodiment of the present disclosure, there is provided a bearing device for a generator that includes an insulating material for suppressing axial current, and that allows for easy adjustment of the gap between the bearing ring and the bearing, a power generation device, and a turbine power generation system.

[0009] Fig. 4 is a schematic diagram showing a general configuration of a turbine power generation system 2 according to one embodiment. Fig. 5 is a diagram showing an example of a cross section along the axial direction of the configuration of the bearing device 6 side in the turbine power generation system 2. Fig. 6 is a diagram showing an example of a cross section perpendicular to the axial direction of a part of the bearing device 6. Fig. 7 is a diagram showing an example of an arrangement of the bearing ring 24, the pads 28, etc. when viewed axially from the P direction in Fig. 2. Fig. 8 is a diagram showing an example of a cross section perpendicular to the axial direction of a part of the bearing device 8.

[0010] Several embodiments of the present disclosure will be described below with reference to the accompanying drawings. However, the dimensions, materials, shapes, relative arrangements, etc. of components described as embodiments or shown in the drawings are merely illustrative examples and are not intended to limit the scope of the invention. For example, expressions expressing relative or absolute arrangements, such as "in a certain direction," "along a certain direction," "parallel," "orthogonal," "center," "concentric," or "coaxial," not only strictly express such arrangements, but also express relative displacements with a tolerance or angle or distance to the extent that the same function is achieved. For example, expressions expressing the equality of things, such as "same," "equal," and "homogeneous," not only express strict equality, but also express tolerance or differences to the extent that the same function is achieved. For example, expressions expressing shapes such as a square or cylindrical shape not only express shapes such as a square or cylindrical shape in the strict geometric sense, but also express shapes including concave and convex portions, chamfered portions, etc., to the extent that the same effect is achieved. On the other hand, the expressions "comprise," "include," "have," "includes," or "have" of one element are not exclusive expressions that exclude the presence of other elements.

[0011] 1 is a schematic diagram showing a general configuration of a turbine power generation system 2 according to one embodiment. As shown in FIG. 1, the turbine power generation system 2 includes a generator 4, a bearing device 6, a bearing device 8, and a turbine 10.

[0012] The generator 4 includes a rotor 12, a stator core 14, and a stator casing 16 that houses the rotor 12 and the stator core 14. The stator core 14 and the stator casing 16 form a stator.

[0013] The bearing device 6 is configured to rotatably support one end side of the rotor 12 in the axial direction of the generator 4. In the illustrated exemplary embodiment, the bearing device 6 rotatably supports the rotor 12 on the side of the rotor 12 opposite to the turbine 10 in the axial direction of the generator 4.

[0014] The bearing device 8 is configured to rotatably support the other end side of the rotor 12 in the axial direction of the generator 4. In the illustrated exemplary embodiment, the bearing device 8 rotatably supports the rotor 12 on the turbine 10 side of the rotor 12 in the axial direction of the generator 4.

[0015] The turbine 10 is connected to the end of the rotor 12 on the bearing device 8 side, and the rotation of the turbine 10 is transmitted to the rotor 12, causing the rotor 12 to rotate, thereby causing the generator 4 to generate electric power. The generator 4, the bearing device 6, and the bearing device 8 constitute the power generation device 3.

[0016] In the following, unless otherwise specified, "axial direction" means the axial direction of the generator 4, i.e., the axial direction of the rotor 12; "radial direction" means the radial direction of the generator 4, i.e., the radial direction of the rotor 12; and "circumferential direction" means the circumferential direction of the generator 4, i.e., the circumferential direction of the rotor 12, unless otherwise specified.

[0017] Fig. 2 is a diagram showing an example of a cross section along the axial direction of the configuration of the bearing device 6 side in the turbine power generation system 2. Fig. 3 is a diagram showing an example of a cross section perpendicular to the axial direction of a part of the bearing device 6.

[0018] 2 and 3 , the bearing device 6 includes a bearing 20, a bearing casing 22, a bearing ring 24, an insulating member 26, a plurality of pads 28, a plurality of liners 29, and a plurality of bolts 30. The bearing 20, the bearing ring 24, and the insulating member 26 are each configured in an annular shape, and the axial direction of the bearing 20, the bearing ring 24, and the insulating member 26 coincides or substantially coincides with the axial direction of the rotor 12, the radial direction of the bearing 20, the bearing ring 24, and the insulating member 26 coincides or substantially coincides with the radial direction of the rotor 12, and the circumferential direction of the bearing 20, the bearing ring 24, and the insulating member 26 coincides or substantially coincides with the circumferential direction of the rotor 12. For this reason, the axial direction, radial direction, and circumferential direction of the bearing 20, the bearing ring 24, and the insulating member 26 will hereinafter be simply referred to as the "axial direction," the "circumferential direction," and the "radial direction."

[0019] The bearing 20 is configured to rotatably support the rotor 12 on the axial side of the rotor 12 opposite the turbine 10. In the illustrated exemplary embodiment, the bearing 20 is configured in an annular shape so as to surround the shaft portion of the rotor 12, and is configured so as to be separable into an upper bearing half 32 and a lower bearing half 34 with a horizontal plane H1 including a central axis L1 of the bearing 20 as the boundary.

[0020] The bearing casing 22 houses the bearing 20, the bearing ring 24, the insulating member 26, and a plurality of pads 28. In the illustrated exemplary embodiment, the bearing casing 22 includes an end bracket 36 and a bearing cap 38 that is configured separately from the end bracket 36, and the bearing cap 38 is configured to be removable from the end bracket 36.

[0021] The bearing cap 38 has a generally semi-cylindrical shape and is provided above a horizontal plane H1 that includes the central axis L1 of the bearing 20. The bearing cap 38 is provided so as to cover the bearing 20, the bearing ring 24, and the insulating member 26 from above in the vertical direction.

[0022] The end bracket 36 is annular and configured to accommodate the bearing 20, bearing ring 24, insulating member 26, multiple pads 28, and bearing cap 38. A lubricating oil supply passage (not shown) is formed inside the end bracket 36, and lubricating oil is supplied to the bearing 20 via the lubricating oil supply passage. For example, as shown in FIG. 2 , the end bracket 36 includes a cylindrical portion 40, an inclined wall portion 42, a ring plate portion 44, multiple radial rib portions 46, and a bearing ring support portion 48. The cylindrical portion 40 accommodates the bearing 20, bearing ring 24, insulating member 26, multiple pads 28, and bearing cap 38, and the inclined wall portion 42 is connected to the end of the cylindrical portion 40 on the generator 4 side. The inclined wall portion 42 is annular and configured so that the inner and outer diameters of the inclined wall portion 42 decrease with increasing distance from the cylindrical portion 40. An inner peripheral end of the ring plate portion 44 is connected to the outer peripheral surface of the cylindrical portion 40, and an outer peripheral end of the ring plate portion 44 is fixed to the stator casing 16. The plurality of radial ribs 46 are flat plate portions arranged radially when viewed in the axial direction, and each of the plurality of radial ribs 46 is formed in a flat plate shape along a plane perpendicular to the surface of the ring plate portion 44. The radially inner end of the radial rib portion 46 is connected to the outer peripheral surface of the cylindrical portion 40, and the axial end of the radial rib portion 46 on the generator 4 side is connected to the surface of the ring plate portion 44 opposite to the generator 4.

[0023] The bearing ring support portion 48 protrudes radially inward from the lower half of the cylindrical portion 40 and supports the bearing ring 24 from below via the insulating member 26 .

[0024] The bearing ring 24 is configured in an annular shape so as to surround the bearing 20, and is provided between the bearing casing 22 and the bearing 20. The bearing ring 24 is configured so as to be separable into an upper half 50 and a lower half 52, with a horizontal plane H2 including the central axis L2 of the bearing ring 24 as the boundary.

[0025] The insulating member 26 is configured in an annular shape so as to surround the bearing ring 24, with an upper half 26a of the insulating member 26 being provided between the outer peripheral surface 24a of the bearing ring 24 and the inner surface of the bearing casing 22 (in the illustrated example, the inner surface 38a of the bearing cap 38), and a lower half 26b (see FIG. 2) of the insulating member 26 being provided between the outer peripheral surface 24a of the bearing ring 24 and the bearing ring support portion 48 of the end bracket 36. There are no particular restrictions on the material of the insulating member 26, but the insulating member 26 may be, for example, an epoxy resin-impregnated glass cloth laminate, and the insulating member 26 may have an insulation resistance of, for example, 1×10 １２ It may be Ω or more.

[0026] For example, as shown in FIG. 3 , each of the pads 28 is provided on the inner circumferential surface 24b of the bearing ring 24 and is arranged to face the outer circumferential surface 20a of the bearing 20 across a gap g (back gap) when the bearing ring 24 is loaded by the rotor 12. In the illustrated exemplary embodiment, the pads 28 include a central pad 28A and a pair of oblique pads 28B, 28C. The central pad 28A and the pair of oblique pads 28B, 28C each have the same shape. The central pad 28A is provided at the uppermost position on the inner circumferential surface 24b of the bearing ring 24 so as to intersect with a vertical line LA that is perpendicular to the central axis L2 of the bearing ring 24. The oblique pad 28B is arranged above the central axis L2 of the bearing ring 24 and circumferentially offset from the central pad 28A. The inclined pad 28C is disposed above the central axis L2 of the bearing ring 24 and is shifted circumferentially from the central pad 28A to the opposite side of the inclined pad 28B. That is, the central pad 28A is disposed circumferentially between the pair of inclined pads 28B, 28C. Each of the pads 28A to 28C is fastened to the bearing ring 24 by a fastening member such as a bolt (not shown).

[0027] The surface 20h of the bearing 20 facing each of the pads 28A to 28C is formed by a portion of a spherical surface, and the surface 28a of each of the pads 28A to 28C facing the bearing 20 is formed by a portion of a spherical surface.

[0028] The multiple liners 29 include at least one liner 29A sandwiched between the inner circumferential surface 24b of the bearing ring 24 and the central pad 28A, at least one liner 29B sandwiched between the inner circumferential surface 24b of the bearing ring 24 and the inclined pad 28B, and at least one liner 29C sandwiched between the inner circumferential surface 24b of the bearing ring 24 and the inclined pad 28C. Each of the liners 29A to 29C is fixed to the bearing ring 24 by placing the corresponding pad 28A to 28C on the corresponding pad and fastening the corresponding pad to the bearing ring 24 with a fastening member such as a bolt (not shown).

[0029] The plurality of bolts 30 are provided at intervals in the circumferential direction and are configured to fasten the bearing ring 24 and the bearing cap 38. In the illustrated exemplary embodiment, each of the bolts 30 extends radially from the inner peripheral surface side of the bearing ring 24, through the bearing ring 24, and to the bearing cap 38.

[0030] Fig. 4 is a diagram showing an example of the arrangement of the bearing ring 24, pads 28, etc. when viewed axially from the direction P in Fig. 2. Fig. 5 is a diagram showing an example of a cross section taken along line A-A in Fig. 4.

[0031] 3 to 5, each of pads 28A to 28C includes a pad main body 58 that includes a surface 28a that faces the outer peripheral surface 20a of bearing 20 (see FIG. 3), and an engagement portion 60 that protrudes radially outward from pad main body 58 and engages with bearing ring 24. Pads 28A to 28C have the same configuration, and in the following, a description that simply includes a reference to pad 28 means a description common to pads 28A to 28C.

[0032] As shown in Fig. 5, the engaging portion 60 of the pad 28 protrudes radially outward from one axial end 61 of the pad main body 58 and engages with the bearing ring 24. As shown in Fig. 4, the pad 28 includes a circumferential abutment surface 60a (circumferential reference surface) that abuts against the bearing ring 24 in the circumferential direction, and the pad 28 is positioned in the circumferential direction by the circumferential abutment surface 60a abutting against the bearing ring 24.

[0033] 4, a plurality of recesses 62A, 62B, 62C into which the engaging portions 60 of the pads 28A to 28C are respectively fitted are formed at intervals in the circumferential direction on the inner peripheral surface 24b of the bearing ring 24. In the example shown, each of the recesses 62A to 62C is a groove formed at one axial end of the inner peripheral surface 24b of the bearing ring 24. Note that the recesses 62A to 62C have the same configuration, and in the following, a description simply including the term recess 62 means a description common to the recesses 62A to 62C.

[0034] In the illustrated exemplary embodiment, the pads 28 are positioned in the circumferential direction by abutting a circumferential abutment surface 60a of the engagement portion 60 of the pad 28 against a wall surface 62a, which is on the downstream side in the rotation direction R of the rotor 12, of the inner surface of the recess 62 in the inner circumferential surface 24b of the bearing ring 24. Note that the width W1 of the pads 28 in the directions perpendicular to both the axial and radial directions is smaller than the width W2 of the recess 62 in the directions perpendicular to both the axial and radial directions.

[0035] As shown in FIG. 5, the engagement portion 60 of the pad 28 includes an axial abutment surface 60b (axial reference surface) that abuts against the bearing ring 24 in the axial direction, and the axial abutment surface 60b abuts against a wall surface 62b on one axial side of the inner surface of the recess 62 of the bearing ring 24, thereby positioning the pad 28 in the axial direction.

[0036] The radial depth D of the recess 62 in the bearing ring 24 is greater than the radial protrusion H of the engagement portion 60 from the pad main body 58. Furthermore, if the thickness of the liner 29 sandwiched between the pad 28 and the bearing ring 24 is t (however, if multiple liners 29 are sandwiched between one pad 28 and the bearing ring 24, the total thickness of the multiple liners) then the relationship H>t may be satisfied.

[0037] The following describes the effects of the above-described bearing device 6. With the bearing device 6, the dimension of the gap g between the bearing 20 and the pads 28 (i.e., the gap between the bearing ring 24 and the bearing 20) can be easily adjusted by adjusting at least one of the thickness and number of the liners 29, which are sandwiched between the pads 28 provided on the inner diameter side of the bearing ring 24 and the inner circumferential surface 24b of the bearing ring 24. Therefore, even if no pads can be provided between the outer circumferential surface 24a of the bearing ring 24 and the inner surface 38a of the bearing casing 22 because the insulating member 26 is provided between the outer circumferential surface 24a of the bearing ring 24 and the inner surface 38a of the bearing casing 22, the dimension of the gap between the bearing ring 24 and the bearing 20 can be easily adjusted.

[0038] Furthermore, if the surface 20h of the bearing 20 facing the pad 28 and the surface 28a of the pad 28 facing the bearing 20 are formed by portions of a spherical surface, even a slight deviation in the relative position of the pad 28 with respect to the bearing 20 is likely to significantly reduce the bearing performance of the bearing device 6. However, by including an engagement portion 60 where the pad 28 engages with the bearing ring 24, as in the above-mentioned bearing device 6, it is possible to suppress deviation in the relative position of the pad 28 with respect to the bearing 20, thereby stabilizing the bearing performance.

[0039] Furthermore, the pad 28 is positioned in the axial direction by the circumferential contact surface 60a of the engaging portion 60 abutting against the bearing ring 24 in the circumferential direction. Therefore, even if the surface 20h of the bearing 20 facing the pad 28 and the surface 28a of the pad 28 facing the bearing 20 are each formed of a part of a spherical surface, it is possible to suppress deviation in the circumferential position of the pad 28 relative to the bearing 20, thereby stabilizing bearing performance.

[0040] Furthermore, the pad 28 is positioned in the axial direction by the axial abutment surface 60b of the engaging portion 60 abutting against the bearing ring 24 in the axial direction. Therefore, even if the surface 20h of the bearing 20 facing the pad 28 and the surface 28a of the pad 28 facing the bearing 20 are each formed of a part of a spherical surface, it is possible to suppress deviation in the axial position of the pad 28 relative to the bearing 20, thereby stabilizing bearing performance.

[0041] Furthermore, the circumferential abutment surface 60a abuts against a wall surface 62a, which is on the downstream side in the rotation direction of the rotor 12, of the inner surface of the recess 62 of the bearing ring 24. Therefore, even if the pad 28 is subjected to a load in the rotation direction of the rotor 12, the wall surface 62a, which is on the downstream side in the rotation direction of the rotor 12, of the inner surface of the recess 62 of the bearing ring 24, can prevent the position of the pad 28 from shifting downstream in the rotation direction of the rotor 12. Therefore, it is possible to effectively prevent deviation of the circumferential position of the pad 28 relative to the bearing 20, and stabilize bearing performance.

[0042] Furthermore, by providing a pair of inclined pads 28B, 28C together with the central pad 28A, even if the bearing 20 is subjected to an oblique load that intersects with the vertical direction due to vibration of the rotor 12 or the like, the inclined pads 28B, 28C can suppress displacement of the bearing 20, thereby stabilizing bearing performance.

[0043] Fig. 6 is a diagram showing an example of a cross section perpendicular to the axial direction of a portion of the bearing device 8 shown in Fig. 1. As shown in Fig. 6, the bearing device 8 includes a bearing 64, a bearing casing 65, a bearing ring 66, a plurality of pads 67, a plurality of liners 68, and a plurality of bolts 69. As shown in Fig. 6, no insulating member is provided between the bearing 64 and the bearing casing 70 in the bearing device 8.

[0044] The bearing 64 is configured to rotatably support the rotor 12 on the turbine 10 (see FIG. 1 ) side of the rotor 12 in the axial direction. In the illustrated exemplary embodiment, the bearing 64 is configured in an annular shape so as to surround the shaft portion of the rotor 12, and is configured so as to be separable into an upper bearing half 74 and a lower bearing half 75 with a horizontal plane H3 including a central axis L3 of the bearing 64 as the boundary.

[0045] The bearing casing 65 houses the bearings 64, the bearing ring 66, and a plurality of pads 67. In the illustrated exemplary embodiment, the bearing casing 65 includes an end bracket (not shown) and a bearing cap 70 configured separately from the end bracket, and the bearing cap 70 is configured to be removable from the end bracket.

[0046] The bearing cap 70 has a generally semi-cylindrical shape and is provided above a horizontal plane H3 that includes the central axis L3 of the bearing 64. The bearing cap 70 is provided so as to cover the bearing 64 and the bearing ring 66 from above in the vertical direction.

[0047] The bearing ring 66 is configured in an annular shape so as to surround the bearing 64, and is provided between the bearing casing 65 and the bearing 64. The bearing ring 66 is configured so as to be separable into an upper half 76 of the bearing ring and a lower half 76 of the bearing ring (not shown), with a horizontal plane H4 including a central axis L4 of the bearing ring 66 as the boundary.

[0048] Each of the multiple pads 67 is provided on the outer peripheral surface 66a of the bearing ring 66 and is held between the inner peripheral surface of the bearing cap 70 and the outer peripheral surface 66a of the bearing ring 66. In the illustrated exemplary embodiment, the multiple pads 67 include a central pad 67A and a pair of horizontal pads 67B, 67C. The central pad 67A is provided at the top of the outer peripheral surface 66a of the bearing ring 66 so as to intersect with a vertical line LB that is perpendicular to the central axis L4 of the bearing ring 66. The horizontal pad 67B is located on or near a horizontal plane H4 that includes the central axis L4 of the bearing ring 66, and the horizontal pad 67C is located on the opposite side of the horizontal pad 67B across the rotor 12. In the illustrated example, a plurality of recesses 72A, 72B, 72C are formed at circumferential intervals on the outer peripheral surface 66a of the bearing ring 66, and the pads 67A, 67B, 67C are fitted into the recesses 72A, 72B, 72C, respectively.

[0049] A surface 64h of the bearing 64 facing the bearing ring 66 is formed by a part of a spherical surface, and a surface 66i of the bearing ring 66 facing the bearing 64 is formed by a part of a spherical surface.

[0050] The multiple liners 68 include at least one liner 68A sandwiched between the outer peripheral surface 66a of the bearing ring 66 and the central pad 67A, at least one liner 68B sandwiched between the outer peripheral surface 66a of the bearing ring 66 and the horizontal pad 67B, and at least one liner 68C sandwiched between the outer peripheral surface 66a of the bearing ring 66 and the horizontal pad 67C.

[0051] The plurality of bolts 69 are provided at intervals in the circumferential direction and configured to fasten the bearing ring 66 to the bearing cap 70. In the illustrated exemplary embodiment, each of the bolts 69 extends radially from the inner peripheral surface side of the bearing ring 66, through the bearing ring 66, and to the bearing cap 70.

[0052] As described above, of the bearing devices 6 and 8 of the turbine power generation system 2, only the bearing device 6 is provided with the insulating member 26 between the bearing ring 24 and the bearing casing 22, and the bearing device 8 is not provided with an insulating member between the bearing ring 66 and the bearing casing 65. For this reason, for the bearing device 8, the pads 67 and liners 72 can be provided between the bearing ring 66 and the bearing casing 65 of the bearing device 8, and the size of the gap between the bearing 64 and the bearing ring 66 can be easily adjusted by adjusting at least one of the thickness and the number of liners 72.

[0053] In this way, in the bearing device 6 which has an insulating member 26 between the outer peripheral surface 24a of the bearing ring 24 and the inner surface 38a of the bearing casing 22, and in the bearing device 8 which does not have an insulating member between the outer peripheral surface 66a of the bearing ring 66 and the inner surface of the bearing casing 65, by making the position of the pad different between the inner diameter side of the bearing casing 22 and the outer diameter side of the bearing casing 65, it is possible to suppress axial currents with a simple configuration and easily adjust the dimension of the gap g between the outer peripheral surface of the bearing and the pad or bearing ring in each of the bearing devices 6 and 8.

[0054] The present disclosure is not limited to the above-described embodiments, and includes modifications of the above-described embodiments and appropriate combinations of these modifications. For example, in the turbine power generation system 2 shown in FIG. 1 , the bearing device 6 and the bearing device 8 may be reversed in position. That is, the bearing device 6 including the insulating member 26 may be configured to rotatably support the rotor on the turbine side of the generator 4, and the bearing device 8 not including the insulating member may be configured to rotatably support the rotor on the opposite side of the generator 4 from the turbine.

[0055] Furthermore, for example, in the above-described embodiment, the engaging portion 60 of the pad 28 is configured to protrude radially outward from the pad main body 58 and engage with the recess 62 of the bearing ring 24. However, in other embodiments, the engaging portion may be a recess formed on the radially outer surface of the pad main body. In this case, the bearing ring may have a protrusion that protrudes radially inward from its inner peripheral surface and is configured to engage with the recess in the pad main body. In this case, the inner surface of the recess formed in the pad main body may include a circumferential abutment surface that abuts against the bearing ring in the circumferential direction of the bearing ring, and an axial abutment surface that abuts against the bearing ring in the axial direction of the bearing ring.

[0056] The contents described in each of the above embodiments can be understood, for example, as follows.

[0057] (1) A bearing device for a generator (e.g., the above-mentioned bearing device 6) according to at least one embodiment of the present disclosure comprises: a bearing (e.g., the above-mentioned bearing 20) configured to rotatably support a rotor (e.g., the above-mentioned rotor 12) of a generator (e.g., the above-mentioned generator 4); a bearing casing (e.g., the above-mentioned bearing casing 22) that houses the bearing; a bearing ring (e.g., the above-mentioned bearing ring 24) provided between the bearing casing and the bearing; an insulating member (e.g., the above-mentioned insulating member 26) provided between the outer circumferential surface of the bearing ring and the inner surface of the bearing casing; a first pad (e.g., the above-mentioned pad 28, 28A, 28B, or 28C) provided on the inner diameter side of the bearing ring and arranged to face the outer circumferential surface of the bearing with a gap therebetween; and a liner (e.g., the above-mentioned liner 29) sandwiched between the inner circumferential surface of the bearing ring and the first pad.

[0058] According to the generator bearing device described in (1) above, the dimension of the gap between the bearing ring and the bearing (i.e., the gap between the bearing and the pads) can be easily adjusted by adjusting at least one of the thickness and the number of liners sandwiched between the pads provided on the inner diameter side of the bearing ring and the inner circumferential surface of the bearing ring. Therefore, even if pads cannot be provided between the outer circumferential surface of the bearing ring and the inner surface of the bearing casing because an insulating member for suppressing axial current is provided between the outer circumferential surface of the bearing ring and the inner surface of the bearing casing, the dimension of the gap between the bearing and the bearing ring can be easily adjusted.

[0059] (2) In some embodiments, in the generator bearing device described in (1) above, the surface of the bearing facing the first pad (e.g., the above-mentioned surface 20h) is configured by a portion of a spherical surface, the surface of the first pad facing the bearing (e.g., the above-mentioned surface 28a) is configured by a portion of a spherical surface, and the first pad includes an engaging portion (e.g., the above-mentioned engaging portion 60) that engages with the bearing ring.

[0060] When the surface of the bearing facing the first pad and the surface of the first pad facing the bearing are each composed of a portion of a spherical surface, even a slight deviation in the relative position of the first pad with respect to the bearing is likely to significantly reduce the performance of the bearing. However, by including an engagement portion in which the first pad engages with the bearing ring as described in (2) above, it is possible to suppress deviation in the relative position of the first pad with respect to the bearing and stabilize the bearing performance.

[0061] (3) In some embodiments, in the generator bearing device described in (2) above, the engaging portion includes an axial abutment surface (e.g., the above-mentioned axial abutment surface 60b) that abuts against the bearing ring in the axial direction of the bearing ring.

[0062] According to the generator bearing device described in (3) above, the axial abutment surface of the engagement portion abuts against the bearing ring in the axial direction of the bearing ring, thereby positioning the first pad in the axial direction of the bearing ring. Therefore, even if the surface of the bearing facing the first pad and the surface of the first pad facing the bearing are each formed of a part of a sphere, it is possible to suppress deviation in the axial position of the first pad relative to the bearing, thereby stabilizing bearing performance.

[0063] (4) In some embodiments, in the generator bearing device described in (3) above, the first pad includes a pad main body portion (e.g., the pad main body portion 58 described above) facing the outer peripheral surface of the bearing, and the engagement portion is arranged to protrude from the pad main body portion in the radial direction of the bearing ring.

[0064] According to the generator bearing device described in (4) above, the first pad is positioned in the axial direction of the bearing ring by an axial abutment surface provided on an engagement portion that protrudes from the pad main body in the radial direction of the bearing ring abutting against the bearing ring in the axial direction. Therefore, even if the surface of the bearing facing the first pad and the surface of the first pad facing the bearing are each formed of a part of a sphere, it is possible to suppress deviation in the axial position of the first pad relative to the bearing, thereby stabilizing bearing performance.

[0065] (5) In some embodiments, in the generator bearing device described in (2) above, the engaging portion includes a circumferential abutment surface (e.g., the above-mentioned circumferential abutment surface 60a) that abuts against the bearing ring in a direction along the circumferential direction of the bearing ring.

[0066] According to the generator bearing device described in (5) above, the circumferential abutment surface of the engagement portion abuts against the bearing ring in a direction along the circumferential direction of the bearing ring, thereby positioning the first pad in the circumferential direction of the bearing ring. Therefore, even if the surface of the bearing facing the first pad and the surface of the first pad facing the bearing are each formed of a part of a sphere, it is possible to suppress deviation in the circumferential position of the first pad relative to the bearing, thereby stabilizing bearing performance.

[0067] (6) In some embodiments, in the generator bearing device described in any of (2) to (5) above, a recess (e.g., the above-mentioned recess 62A, 62B, or 62C) is formed on the inner circumferential surface of the bearing ring, and the circumferential abutment surface abuts against the inner surface of the recess of the bearing ring.

[0068] According to the generator bearing device described in (6) above, the circumferential abutment surface of the engagement portion abuts against the inner surface of the recess of the bearing ring in a direction along the circumferential direction of the bearing ring, thereby positioning the first pad in the circumferential direction of the bearing ring. Therefore, even if the surface of the bearing facing the first pad and the surface of the first pad facing the bearing are each formed of a part of a sphere, it is possible to suppress deviation in the circumferential position of the first pad relative to the bearing, thereby stabilizing bearing performance.

[0069] (7) In some embodiments, in the generator bearing device described in any of (1) to (6) above, the circumferential abutment surface abuts against a wall surface (e.g., the above-mentioned wall surface 62a) on the inner surface of the recess of the bearing ring that is downstream in the rotation direction of the rotor.

[0070] According to the generator bearing device described in (7) above, even if the first pad is subjected to a load in the direction of rotor rotation, the downstream wall surface of the inner surface of the recess in the bearing ring can prevent the first pad from shifting downstream in the direction of rotor rotation, thereby effectively preventing deviation of the circumferential position of the first pad relative to the bearing and stabilizing bearing performance.

[0071] (8) In some embodiments, the generator bearing device described in any of (1) to (7) above further comprises a pair of inclined pads (e.g., the above-mentioned inclined pads 28B, 28C) provided on the inner surface of the bearing ring and arranged to face the outer surface of the bearing with a gap therebetween, and a liner (e.g., the above-mentioned liners 29B, 29C) sandwiched between the inner surface of the bearing ring and each of the pair of inclined pads, wherein the first pad is arranged between the pair of inclined pads in the circumferential direction of the bearing ring.

[0072] According to the generator bearing device described in (8) above, even if the bearing is subjected to a load in an oblique direction that intersects with the vertical direction due to rotor vibration or the like, the inclined pad can suppress bearing displacement and stabilize bearing performance.

[0073] (9) A bearing device for a generator according to at least one embodiment of the present disclosure comprises: a first bearing device (for example, the above-mentioned bearing device 6) configured to rotatably support one end side of a rotor of a generator; and a second bearing device (for example, the above-mentioned bearing device 8) configured to rotatably support the other end side of the rotor, wherein the first bearing device is the bearing device for a generator according to any one of (1) to (8) above, and the second bearing device comprises: a bearing (for example, the above-mentioned bearing 64) configured to rotatably support the other end side of the rotor of the generator; a bearing casing (for example, the above-mentioned bearing casing 65) that houses the bearing of the second bearing device; a bearing ring (for example, the above-mentioned bearing ring 66) provided between the bearing casing of the second bearing device and the bearing of the second bearing device; and a pad (for example, the above-mentioned pad 67) sandwiched between the outer circumferential surface of the bearing ring of the second bearing device and the inner surface of the bearing casing of the second bearing device. a liner (for example, the above-mentioned liner 68) sandwiched between the outer peripheral surface of the bearing ring of the second bearing device and the pad.

[0074] According to the generator bearing device described in (9) above, of the first and second bearing devices, only the first bearing device has an insulating member between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing, while the second bearing device does not have an insulating member between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing. Therefore, for the second bearing device, pads and liners can be provided between the outer peripheral surface of the bearing ring of the second bearing device and the inner surface of the bearing casing of the second bearing device, and the size of the gap between the bearing and the pads can be easily adjusted by adjusting at least one of the thickness and number of liners. Thus, in the first bearing device that has an insulating member between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing and the second bearing device that does not have an insulating member between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing, by providing pads at different positions on the inner diameter side and the outer diameter side of the bearing casing, it is possible to suppress axial currents with a simple configuration and easily adjust the size of the gap between the outer peripheral surface of the bearing and the pads or bearing ring in each of the first and second bearing devices.

[0075] (10) A turbine power generation system according to at least one embodiment of the present disclosure comprises: a power generation device as described in (9) above; and a turbine (e.g., the turbine 10 described above) coupled to the rotor of the generator, wherein the first bearing device is configured to support the rotor on the opposite side of the rotor from the turbine in the axial direction of the generator.

[0076] In a typical turbine generator system, an insulating member is provided between the outer peripheral surface of the bearing ring and the inner surface of the bearing casing of a first bearing device that supports the rotor on the side of the rotor opposite the turbine in the axial direction of the generator. Therefore, as described in (10) above, by using the generator described in (9) above in such a typical turbine generator system, it is possible to easily adjust the size of the gap between the bearing and the pad while suppressing the axial current with a simple configuration.

[0077] 2 Turbine power generation system 28, 67 Pad 3 Power generation device 4 Generator 6, 8 Bearing device (bearing device for generator) 10 Turbine 12 Rotor 14 Stator core 16 Stator casing 20, 64 Bearing 20a, 24a, 66a Outer surface 20h, 28a, 64h, 66i Surface 22, 65 Bearing casing 24, 66 Bearing ring 24b Inner surface 26 Insulating member 26a Upper half 26b Lower half 28A, 67A Central pad 28B, 28C Inclined pad 29, 29A, 29B, 29C, 68, 68A, 68B, 68C Liner 30, 69 Bolt 32, 74 Bearing upper half 34, 75 Bearing lower half 36 End bracket 38, 70 Bearing cap 38a Inner surface 40 Cylindrical portion 42 Inclined wall portion 44 Ring plate portion 46 Radial rib portion 48 Bearing ring support portion 50, 76 Bearing ring upper half portion 52 Bearing ring lower half portion 58 Pad body portion 60 Engagement portion 60a Circumferential contact surface 60b Axial contact surface 61 End portion 62, 62A, 62B, 62C, 72A, 72B, 72C Recessed portion 62a, 62b Wall surface 67B, 67C Horizontal pad

Claims

1. A bearing device for a generator comprising: a bearing configured to rotatably support a rotor of a generator; a bearing casing that houses the bearing; a bearing ring provided between the bearing casing and the bearing; an insulating member provided between the outer circumferential surface of the bearing ring and the inner surface of the bearing casing; a first pad provided on the inner circumferential surface of the bearing ring and arranged to face the outer circumferential surface of the bearing with a gap between them; and a liner sandwiched between the inner circumferential surface of the bearing ring and the first pad.

2. A generator bearing device as described in claim 1, wherein a surface of the bearing facing the first pad is constituted by a portion of a spherical surface, a surface of the first pad facing the bearing is constituted by a portion of a spherical surface, and the first pad includes an engagement portion that engages with the bearing ring.

3. The generator bearing device according to claim 2, wherein said engaging portion includes an axial contact surface that contacts said bearing ring in the axial direction of said bearing ring.

4. A generator bearing device as described in claim 3, wherein the first pad includes a pad main body portion facing the outer peripheral surface of the bearing, and the engagement portion is arranged to protrude from the pad main body portion in the radial direction of the bearing ring.

5. A generator bearing device as set forth in claim 2, wherein said engaging portion includes a circumferential contact surface that contacts said bearing ring in a direction along the circumferential direction of said bearing ring.

6. A generator bearing device as set forth in claim 5, wherein a recess is formed on the inner peripheral surface of the bearing ring, and the circumferential contact surface abuts against an inner surface of the recess of the bearing ring.

7. A generator bearing device as set forth in claim 6, wherein the circumferential contact surface contacts a wall surface of the inner surface of the recess of the bearing ring that is downstream in the rotation direction of the rotor.

8. A generator bearing device as described in claim 1, further comprising: a pair of inclined pads provided on the inner surface of the bearing ring and arranged to face the outer surface of the bearing with a gap between them; and a liner sandwiched between the inner surface of the bearing ring and each of the pair of inclined pads, wherein the first pad is arranged between the pair of inclined pads in the circumferential direction of the bearing ring.

9. A power generating device comprising: a first bearing device configured to rotatably support one end side of a rotor of a generator; and a second bearing device configured to rotatably support the other end side of the rotor, wherein the first bearing device is a bearing device for a generator as defined in any one of claims 1 to 8, and the second bearing device comprises: an annular bearing configured to rotatably support the other end side of the rotor of the generator; a bearing casing that accommodates the bearing of the second bearing device; a bearing ring provided between the bearing casing of the second bearing device and the bearing of the second bearing device; a pad sandwiched between the outer peripheral surface of the bearing ring of the second bearing device and the inner surface of the bearing casing of the second bearing device; and a liner sandwiched between the outer peripheral surface of the bearing ring of the second bearing device and the pad.

10. A turbine power generation system comprising: a power generation device according to claim 9; and a turbine connected to the rotor of the generator, wherein the first bearing device is configured to support the rotor on an opposite side of the rotor to the turbine in the axial direction of the generator.

Images