JP6898886B2 - Rotating machine and stator damping structure - Google Patents

Description

The present invention relates to a rotary electric machine and a stator damping structure.

In a rotary electric machine, in a rotor core and a stator core, iron loss due to eddy current or the like generated during operation contributes to heat generation and causes a decrease in efficiency. Therefore, reducing the current flow inside each of the rotor core and the stator core is effective in ensuring the efficiency of the rotating electric machine.

For this reason, it is common practice to use a laminated iron core structure in which disc-shaped ferromagnetic steel sheets having an opening in the center are laminated in the axial direction, respectively, for the rotor core and the stator core in the rotary electric machine. There is.

The stator core is arranged so as to surround the rotor core on the outer side in the radial direction of the rotor core through a gap, and is formed in a cylindrical shape as a whole. Further, on the inner surface of the stator core in the radial direction, a plurality of slots are formed which are arranged at intervals in the circumferential direction and penetrate the stator core in the axial direction. Each slot contains the conductor of the stator winding.

In order to form such a stator core, each of the electromagnetic steel sheets constituting the laminated core structure is formed with a central opening and a recess corresponding to each slot. The electrical steel sheets laminated in the axial direction are sandwiched between the inner clampers and the outer clampers arranged at both ends in the axial direction, and are tightened by the tightening rods protruding to both outer sides in the axial direction of the two outer clampers to form an integrated shape as a whole. Maintained.

The inner clamper is provided to hold down each tooth portion formed by the slots adjacent to each other formed in the laminated iron core structure, and the outer clamper is an electromagnetic steel plate laminated in the axial direction via the inner clamper. Tightened from both sides in the axial direction.

Japanese Unexamined Patent Publication No. 2000-50538

In a rotating field type rotary electric machine, a ring in which the stator is deformed into an elliptical shape in a plane in the direction perpendicular to the axis by the rotation of a predetermined number of rotors having magnetic attraction during its operation. Vibration occurs (see Patent Document 1). The electromagnetic vibration that causes this annulus vibration has a frequency twice that of the power supply frequency because it is caused by the electromagnetic force between the poles of the stator.

In the rotary electric machine configured as described above, electromagnetic noise is generated due to electromagnetic vibration, which adversely affects the work in the field.

Therefore, an object of the present invention is to reduce noise caused by annulus vibration of a stator in a rotary electric machine.

In order to achieve the above object, the present invention has a rotor, a plurality of laminates composed of a plurality of electromagnetic steel plates provided on the outer side in the radial direction of the rotor and laminated in the axial direction, and a diameter of the plurality of laminates. A stator having a cylindrical stator core having a stator vibration damping structure that suppresses directional deformation, a stator winding having a stator winding penetrating the inside of the stator core in the axial direction, and rotating the rotor. A rotary electric machine including two bearings that can support the rotor, and the stator vibration damping structure includes two outer clampers arranged so as to sandwich the plurality of laminates in the axial direction and each other in the circumferential direction. Between a plurality of tightening rods arranged so as to be in contact with the radial outer portion of the layered body and tightening the laminated body from both outer sides in the axial direction together with the outer clamper, and the laminated bodies adjacent to each other. A plurality of gap forming portions arranged to form a flow path for cooling gas outward in the radial direction, a rod through hole formed in the gap forming portion through which the tightening rod penetrates, and a plurality of adjacent portions on both sides in the axial direction. A plurality of intermediate restraint members having an annular restraint ring portion for restraining the radial outer side of the electromagnetic steel plate, and the two outer clampers and the intermediate restraint member radially hold the plurality of tightening rods. It is characterized by being restrained by.

Further, the present invention comprises a rotor, a cylindrical stator core having a plurality of laminated bodies composed of a plurality of electromagnetic steel plates laminated in the axial direction, and a stator penetrating the inside of the stator core in the axial direction. It is a stator vibration damping structure of a rotating electric machine including a stator having a winding and two bearings for rotatably supporting the rotor, and is arranged so as to sandwich the plurality of laminates in the axial direction. A plurality of outer clampers arranged so as to come into contact with the radial outer portions of the laminate at intervals in the circumferential direction, and tighten the laminate together with the outer clampers from both outer sides in the axial direction. A tightening rod, a gap forming portion arranged between the laminated bodies adjacent to each other and forming a flow path of a cooling gas to the outside in the radial direction, and a rod through which the tightening rod formed in the gap forming portion penetrates. A plurality of intermediate restraint members having through holes and a plurality of annular restraint ring portions for restraining the radial outer side of the electromagnetic steel plate adjacent to both sides in the axial direction are provided, and the two outer clampers and the intermediate are provided. The restraining member is characterized in that the plurality of tightening rods are restrained in the radial direction.

According to the present invention, it is possible to reduce the noise caused by the ring vibration of the stator in the rotary electric machine.

It is a vertical sectional view which shows the structure of the rotary electric machine which concerns on embodiment. It is an upper half partial vertical sectional view which shows the structure of the stator core of the rotary electric machine which concerns on embodiment, and the periphery thereof. It is a side view which shows the structure of the end part in the axial direction of the stator core of the rotary electric machine which concerns on embodiment. FIG. 5 is a cross-sectional view taken along the line IV-IV of FIG. 5 showing a configuration of an intermediate restraint member of the stator damping structure according to the embodiment. It is a cross-sectional view taken along the line VV of FIG. 4 which shows the structure of the intermediate restraint member of the stator vibration damping structure which concerns on embodiment. It is a VI-VI arrow cross-sectional view of FIG. 4 which shows the structure of the intermediate restraint member of the stator vibration damping structure which concerns on embodiment. It is a development view in the circumferential direction of the arrow from the inside in the radial direction which shows the structure of the intermediate restraint member of the stator vibration damping structure which concerns on embodiment.

Hereinafter, the rotary electric machine and the stator core vibration damping structure according to the present invention will be described with reference to the drawings. Here, parts that are the same as or similar to each other are designated by a common reference numeral, and duplicate description will be omitted.

FIG. 1 is a vertical cross-sectional view showing a configuration of a rotary electric machine according to an embodiment. FIG. 2 is an upper half vertical cross-sectional view showing the configuration of the stator core and its surroundings. Further, FIG. 3 is a side view showing the configuration of the axial end portion of the stator core.

The rotary electric machine 200 has a rotor 10, a stator 20, two bearings 30, a frame 40, and two bearing brackets 45. Hereinafter, the direction in which the rotation axis extends is referred to as the z direction, the direction from the rotation axis of the rotor to the outside in the radial direction is referred to as the r direction, and the rotation direction of the rotor, that is, the circumferential direction is referred to as the θ direction.

The rotor 10 has a rotor shaft 11 and a rotor core 12. The rotor shaft 11 extends in the horizontal direction (z direction). The rotor core 12 has a cylindrical shape and is attached to the outside of the rotor shaft 11 in the radial direction (r direction).

The stator 20 has a stator core 100 and a stator winding 22. The stator core 100 is arranged radially outside the rotor core 12 via a gap 18 and has a cylindrical shape. The stator windings 22 penetrate the stator core 100 in the axial direction and are connected to each other on the outer side of the stator core 100 in the axial direction, or are connected to external wiring. Specifically, the stator core 100 is formed with a plurality of stator slots (not shown) extending radially inward at intervals in the circumferential direction, and the stator winding 22 is fixed. It penetrates through the child slot.

The two bearings 30 rotatably support the rotor 10 on both sides of the rotor shaft 11 in the axial direction with the rotor core 12 interposed therebetween. The frame 40 is arranged on the radial outer side of the stator 20 to house the rotor core 12 and the stator 20. The two bearing brackets 45 are connected to both ends in the axial direction of the frame 40, and each statically supports the bearing 30.

The stator core 100 has a laminate 110, two inner clampers 121, and a stator damping structure 150.

The laminated body 110 is made of a ferromagnetic material laminated in the axial direction and has a plurality of disk-shaped electromagnetic steel sheets 111 having an opening in the center. The laminated body 110 on which the electromagnetic steel plates 111 are laminated has a cylindrical shape, and tooth portions (not shown) are formed on the inner side in the radial direction so as to protrude inward in the radial direction and extend in the axial direction at intervals from each other in the circumferential direction. Has been done. The tooth portions adjacent to each other form a slot (not shown) through which the stator winding 22 passes. The laminated bodies 110 are arranged side by side in the axial direction with each other.

One radial duct 115 is formed between the laminated bodies 110 adjacent to each other. That is, the radial duct 115 is formed so as to be spaced apart from each other for each laminated body 110 in the axial direction. In each of the radial ducts 115, a cooling gas for cooling the inside of the machine, such as air, flows into the stator core 100 from the gap 18 to cool the stator core 100 and to the outside of the stator core 100 in the radial direction. It serves as a flow path for outflow and is formed over the circumferential direction.

The inner clampers 121 are provided on both outer sides in the axial direction of the plurality of laminated bodies 110 arranged. The inner clamper 121 is an annular shape, that is, a disk-shaped plate extending in the radial direction, having an opening in the center, and a flat plate thicker in the axial direction than the electromagnetic steel plate 111. The outer diameter of the inner clamper 121 is substantially equal to the outer diameter of the plurality of laminated electromagnetic steel sheets 111. Further, on the inner side of the inner clamper 121 in the radial direction, a plurality of tooth holders 121a for restraining the tooth portions formed on the electromagnetic steel plate 111 from the outer side in the axial direction are formed.

The stator damping structure 150 has two outer clampers 122, a plurality of tightening rods 123 and an intermediate restraint member 130. Here, the two outer clampers 122 and the plurality of tightening rods 123 also have a function of tightening the laminate 110 and the two inner clampers 121 from both outer sides in the axial direction.

Each of the two outer clampers 122 is provided on the outer side of each of the two inner clampers 121 in the axial direction. The outer clamper 122 is a flat plate that is thicker in the axial direction than the electromagnetic steel plate 111. The outer clamper 122 has an annular shape, that is, a disk shape extending in the radial direction, has an opening 122b in the center, and extends radially outward from the inner clamper 121. Specifically, the outer diameter of the outer clamper 122 is larger than the outer diameter of the inner clamper 121, and the diameter of the opening 122b of the outer clamper 122 is a circle enveloping the base of the tooth holding portion 121a of the inner clamper 121. Is larger than the diameter of. The edge of the opening 122b is formed with a taper so that the thickness in the axial direction becomes thinner toward the inner side in the radial direction.

The plurality of tightening rods 123 are arranged at intervals in the circumferential direction. Further, in the radial direction, each central portion is arranged at a position substantially passing through the radial outer surface of the laminated body 110 and the inner clamper 121, and the radial outer portion of the laminated body 110 is constrained in the radial direction. .. The cross-sectional shape of the tightening rod 123 is rectangular. The radial thickness H1 of the tightening rod 123 is set to a size sufficient to secure the bending rigidity required in the radial direction. The cross-sectional shape of the tightening rod 123 is not limited to a rectangle. A polygon other than a rectangle, or a circle or a semicircle may be used as long as the required flexural rigidity can be secured.

Grooves extending in the axial direction at intervals in the circumferential direction are formed in the outer portion of each laminate 110 in the radial direction so that the tightening rod 123 can pass in the axial direction. Similarly, the inner clamper 121 is also formed with recesses 121b at intervals in the circumferential direction.

The outer clamper 122 is formed with a rod through hole 122a through which the tightening rod 123 penetrates. Both ends of each tightening rod 123 penetrate the rod through holes 122a of the outer clampers 122 on both sides and project outward. These outer protruding portions of the tightening rod 123 are connected to the outer clamper 122 by the fixing portion 124. The fixing portion 124 is, for example, a portion in which the tightening rod 123 is joined to the outer clamper 122 by welding or brazing. Alternatively, the fixing portion 124 may be tightened by a nut so that a bolt head is provided at one end of the tightening rod 123 and a male screw is formed at the other end.

The groove formed in the laminated body 110 and the recess 121b formed in the inner clamper 121 substantially overlap each other with the radial inner portion of the rod through hole 122a formed in the outer clamper 122 in the axial direction. Further, the surface of the inner portion of the tightening rod 123 in the radial direction is formed in a shape and size so as to come into contact with each other in the circumferential direction.

FIG. 4 is a cross-sectional view taken along the line IV-IV of FIG. 5 showing a configuration of an intermediate restraining member of the stator damping structure according to the embodiment. 5 is a cross-sectional view taken along the line VV of FIG. 4, and FIG. 6 is a cross-sectional view taken along the line VI-VI of FIG. Further, FIG. 7 is a development view in the circumferential direction seen from the inside in the radial direction showing the configuration of the intermediate restraint member.

As described above, the intermediate restraining member 130 forms a radial duct 115 formed between two laminated bodies 110 that are axially adjacent to each other, and at the same time, restrains the laminated body 110 in the radial direction and causes a laminated body by electromagnetic vibration. It is an element constituting the stator vibration damping structure 150 that suppresses the radial deformation of the 110.

The intermediate restraint member 130 has a restraint ring portion 131 and a gap forming portion 132. In addition, in FIGS. 4 to 7, the gap forming portion 132 of the intermediate restraint member 130 and the laminated body 110 are in close contact with each other in the axial direction, but in the drawings, they are indicated so as to have a gap in order to clarify the relationship. doing. Further, the radial inner side surface 131b of the restraint ring portion 131 of the intermediate restraint member 130 and the radial outer surface of the laminated body 110 are in contact with each other, but are similarly indicated to have a distance.

The restraint ring portion 131 is an annular member having a width in the axial direction. The radial inner surface 131b of the restraint ring portion 131 comes into contact with each other on the radial outer surface of the laminate 110. The radial thickness H2 of the restraint ring portion 131 is a height required to secure flexural rigidity for reducing electromagnetic vibration to a desired degree, and is based on analysis, experiment, actual machine data, or the like. It is determined. The cross-sectional shape of the restraint ring portion 131 is rectangular, and the radial inner side surface 131b needs to be flat in order to come into contact with the laminate 110 or a curved surface that can be in close contact with the surface of the laminate. As long as the flexural rigidity is ensured, the cross-sectional shape may be, for example, a shape having an arc or the like, a polygonal shape, or the like.

A plurality of gap forming elements 132a extend inward in the radial direction from the central portion in the axial direction of the radial inner side surface 131b of the restraint ring portion 131. The gap forming elements 132a are arranged at intervals in the circumferential direction, and the shape of the front surface when viewed in the axial direction is substantially trapezoidal. The size of each gap forming element 132a in the cross section perpendicular to the axial direction is set to a size that does not protrude from the slot formed radially inside the laminated body 110. The axial thickness T1 of the gap forming element 132a is a thickness that is the axial width of the radial duct 115. The axial thickness T2 of the restraint ring portion 131 is sufficiently larger than the axial thickness of the gap forming portion 132. The plurality of gap forming elements 132a constitute a gap forming portion 132 which is a portion of the intermediate restraint member 130 having a function of forming an axial gap for the radial duct 115 in the stator core 100.

By sandwiching the gap forming portion 132 between two laminated bodies 110 adjacent to each other, the gap forming portion 132 is sandwiched between the end faces of the laminated bodies 110 facing each other in the z direction in the axial direction. Further, it is sandwiched between two gap forming elements 132a adjacent to each other in the θ direction. By being sandwiched in the z direction and the θ direction in this way, a radial individual flow path 135 extending in the r direction is formed.

In the circumferential region between the gap forming elements 132a adjacent to each other in the restraint ring portion 131, a ventilation hole 131a that extends in the circumferential direction and penetrates from the inside in the radial direction to the outside in the radial direction is formed. The width of the ventilation hole 131a in the z direction is not thinner than the thickness of the gap forming element 132a and is about the same. The facing surfaces 131c of the ventilation holes 131a facing each other are parallel to each other. However, in order to reduce the pressure loss due to the expansion of the cooling gas when the cooling gas flows out to the outside in the radial direction, the facing surfaces 131c facing each other are formed so that the distance between them gradually increases toward the outside in the radial direction. You may be.

A plurality of rod through holes 133 are formed in the intermediate restraint member 130 at intervals in the circumferential direction. Each rod through hole 133 spans the restraint ring portion 131 and the gap forming portion 132 in the radial direction. The rod through holes 133 are formed at the same positions as the plurality of rod through holes 122a formed in the outer clamper 122 in the axial direction. On the radial inner surface 131b of the restraint ring portion 131, rod through grooves 133a are formed on both sides of the rod through hole 133 in the axial direction.

Next, the operations of the rotary electric machine 200 and the stator damping structure 150 formed as described above will be described.

First, the flow path configuration function of the cooling gas of the intermediate restraint member 130 will be described. The cooling gas flows from the gap 18 into the respective radial ducts 115 between the laminated bodies 110 adjacent to each other of the stator core 100. The cooling gas that has flowed into the radial duct 115 flows radially outward in the radial individual flow path 135.

The cooling gas that flows through the radial individual flow paths 135 in the laminated body 110 and reaches the restraint ring portion 131 flows into the ventilation holes 131a formed on the downstream side of each flow path in the restraint ring portion 131. .. The cooling gas that has passed through the ventilation hole 131a flows out from the ventilation hole 131a to the radial outside of the restraint ring portion 131, that is, to the radial outside of the laminated body 110. In this way, the cooling flow path in the stator core 100 is secured.

Next, the function of suppressing the radial deformation of the stator core of the intermediate restraint member 130 will be described.

In the range where the restraint ring portion 131 of the intermediate restraint member 130 extends in the z direction, the radial outer surface of the laminated body 110 is restrained by the restraint ring portion 131 having bending rigidity due to a sufficient height H2 in the radial direction as well. ing.

In other parts, the height H1 also has sufficient bending rigidity in the radial direction, and the circumferential direction is constrained by a plurality of tightening rods 123 extending in the z direction. The tightening rod 123 is constrained to move in the radial direction by the outer clamper 122 and the intermediate restraining member 130 at positions spaced apart from each other in the axial direction.

As described above, the stator damping structure 150 is formed in a cage shape having high rigidity in the radial direction by combining the outer clamper 122, the intermediate restraint member 130, and the plurality of tightening rods 123 with each other. The plurality of laminated bodies 110 are restrained from being deformed radially outward by such a stator damping structure 150.

As a result, the annular vibration of the laminated body 110 is suppressed, and the noise due to the annular vibration can be reduced.

[Other Embodiments]
Although the embodiments of the present invention have been described above, the embodiments are presented as examples and are not intended to limit the scope of the invention. For example, in the embodiment, the case of a horizontal rotary electric machine in which the rotor shaft 11 extends in the horizontal direction is shown as an example, but the present invention is not limited to this. It may be a vertical rotary electric machine in which the rotor shaft extends in the vertical direction.

Moreover, you may combine the features of each embodiment. Further, the embodiment can be implemented in various other forms, and various omissions, replacements, and changes can be made without departing from the gist of the invention. The embodiments and variations thereof are included in the scope of the invention described in the claims and the equivalent scope thereof, as are included in the scope and gist of the invention.

10 ... Rotor, 11 ... Rotor shaft, 12 ... Rotor core, 18 ... Air gap, 20 ... Stator, 22 ... Stator winding, 30 ... Bearing, 40 ... Frame, 45 ... Bearing bracket, 100 ... Stator core , 110 ... Laminate, 111 ... Electromagnetic steel plate, 115 ... Radial duct, 121 ... Inner clamper, 121a ... Tooth presser, 121b ... Recessed, 122 ... Outer clamper, 122a ... Rod through hole, 122b ... Opening, 123 ... Tightening Rod, 124 ... Fixed part, 130 ... Intermediate restraint member, 131 ... Restraint ring part, 131a ... Ventilation hole, 131b ... Radial inner surface, 131c ... Opposing surface, 132 ... Gap forming part, 132a ... Gap forming element 133 ... Rod through hole 133a ... Rod through groove, 135 ... Individual flow path in the radial direction, 150 ... Stator vibration damping structure, 200 ... Rotor

Claims (5)

Rotor and
Cylindrical shape having a plurality of laminates made of a plurality of electromagnetic steel plates provided on the outer side in the radial direction of the rotor and laminated in the axial direction, and a stator vibration damping structure for suppressing radial deformation of the plurality of laminates. A stator having a stator core and a stator winding that penetrates the stator core in the axial direction.
Two bearings that rotatably support the rotor,
It is a rotary electric machine equipped with
The stator damping structure
Two outer clampers arranged so as to sandwich the plurality of laminated bodies in the axial direction, and
A plurality of tightening rods arranged so as to come into contact with the radial outer portions of the laminate at intervals in the circumferential direction and tightening the laminate from both outer sides in the axial direction together with the outer clamper.
A gap forming portion arranged between the laminated bodies adjacent to each other to form a flow path of a cooling gas to the outside in the radial direction, and a rod through hole formed in the gap forming portion through which the tightening rod penetrates. A plurality of intermediate restraint members having a plurality of annular restraint ring portions for restraining the radial outer side of the plurality of electromagnetic steel sheets adjacent to both sides in the axial direction, and a plurality of intermediate restraint members.
Equipped with
The two outer clampers and the intermediate restraining member constrain the plurality of tightening rods in the radial direction.
A rotating electric machine that is characterized by that. The first aspect of the present invention, wherein the gap forming portions are arranged so as to be spaced apart from each other in the circumferential direction, and have a plurality of gap forming elements extending inward in the radial direction from the restraint ring portion. Rotating electric machine. The rotary electric machine according to claim 2, wherein the restraint ring portion has ventilation holes formed along the radial direction in a circumferential region sandwiched between portions in which the gap forming elements adjacent to each other are formed. The rod through hole, the rotating electrical machine according to claim 2 or claim 3, characterized in that they are made form the respective root portion of said gap forming elements of the constraining ring portion. A fixing having a rotor, a cylindrical stator core having a plurality of laminates composed of a plurality of electromagnetic steel plates laminated in the axial direction, and a stator winding penetrating the stator core in the axial direction. It is a stator damping structure of a rotating electric machine including a child and two bearings that rotatably support the rotor.
Two outer clampers arranged so as to sandwich the plurality of laminated bodies in the axial direction, and
A plurality of tightening rods arranged so as to come into contact with the radial outer portions of the laminate at intervals in the circumferential direction and tightening the laminate from both outer sides in the axial direction together with the outer clamper.
A gap forming portion arranged between the laminated bodies adjacent to each other to form a flow path of a cooling gas to the outside in the radial direction, and a rod through hole formed in the gap forming portion through which the tightening rod penetrates. A plurality of intermediate restraint members having a plurality of annular restraint ring portions for restraining the radial outer side of the plurality of electromagnetic steel sheets adjacent to both sides in the axial direction, and a plurality of intermediate restraint members.
Equipped with
The two outer clampers and the intermediate restraining member constrain the plurality of tightening rods in the radial direction.
Stator damping structure characterized by this.

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