WO2019220779A1

WO2019220779A1 - Rotor and rotating electrical machine

Info

Publication number: WO2019220779A1
Application number: PCT/JP2019/012878
Authority: WO
Inventors: 仁荒川; 哲也永安; 石川　博章
Original assignee: 三菱電機株式会社
Priority date: 2018-05-14
Filing date: 2019-03-26
Publication date: 2019-11-21
Also published as: JP6854975B2; JPWO2019220779A1

Abstract

A wedge hole 81 is provided to a wedge 8 and has: a first section 86 having a first inner diameter; and a second section 85 having a second inner diameter greater than the first inner diameter, the second section 85 being disposed further outward in the radial direction of a rotor iron core 2 of a rotor 1 than the first section 86. The provision of the first section 86 and the second section 85 stably reduces flow resistance outside the hole exit of the wedge hole 81. As a result, the volume of a cooling gas discharged from the hole exit of the wedge hole 81 is increased, and the cooling capacity of the rotor 1 is enhanced.

Description

Rotor and rotating electric machine

The present invention relates to a rotor having a cooling mechanism and a rotating electric machine.

Conventionally, the radial flow cooling method is widely used in rotating electrical machines such as generators because of its simple structure and high cooling performance. A rotor core of a turbine generator that employs a radial flow cooling system has a plurality of coil slots that are radially formed around the rotation axis. Each coil slot extends in the axial direction, and a plurality of rotor coils are stacked in each coil slot, and a turn insulator is inserted to insulate the rotor coils from each other. Further, the rotor coils stacked in a plurality of stages are fixed by a wedge via an insulator. The wedge has a function of preventing the rotor coil from coming out of the coil slot against a centrifugal force acting when the rotor rotates.

A channel having a U-shaped cross section is formed at the bottom of each coil slot where the rotor coils are stacked on the rotating shaft side over the entire length in the axial direction. Each coil slot is formed with this U-shaped channel and at least one radial path penetrating the rotor coil in the radial direction. The radial path is a radial ventilation path of the rotor. The cooling gas of the rotor is introduced into the U-shaped channel from both ends of the rotor and flows to the center in the axial direction of the rotor. Then, the cooling gas flows into each radial path from the U-shaped channel, and then is discharged into a gap between the rotor and the stator through a hole provided in the insulator and the wedge. Hereinafter, the gap between the rotor and the stator is referred to as an air gap. In this series of operations, the cooling gas absorbs the heat generated in the rotor coil and cools the rotor.

In recent years, the heat generation density or the heat generation amount of the rotor has increased with the reduction in size and capacity of the rotating electrical machine. Therefore, further improvement in the cooling capacity of the rotor is required, and it is necessary to increase the flow rate of the cooling gas flowing through the rotor.

When the cooling gas in the rotor is discharged from the wedge hole to the air gap, the flow of the cooling gas in the rotor collides with the high-speed cooling gas flow in the air gap. In that case, the flow of the cooling gas in the rotor discharged from the wedge hole into the air gap is hindered.

Therefore, there has been proposed a configuration in which the flow of the cooling gas in the rotor is not hindered (see, for example, Patent Document 1 and Patent Document 2).

The rotor of the rotating electrical machine of Patent Document 1 has a V-shaped groove that has a radially outward velocity component with respect to the high-speed gas flow generated in the air gap when the rotor rotates, and the high-speed gas flow at the opening of the wedge hole. Provided on the upstream side. Further, an inclined surface inclined with respect to the radial direction so as to guide the exhaust flow from the wedge hole in the high-speed gas flow direction is provided on the downstream side of the wedge exhaust hole at the high-speed gas flow. Thereby, the merging angle between the high-speed gas flow and the exhaust flow is reduced. As a result, the pressure loss of the exhaust flow at the outlet of the wedge exhaust hole can be reduced.

Moreover, the rotor of the rotary electric machine of patent document 2 describes providing the protrusion which guides the cooling gas flow injected from the wedge hole of a rotor in an air gap in the upstream of the cooling gas flow in an air gap. Has been. Patent Document 2 describes that an inclined surface is provided on the downstream side of the wedge hole for enlarging the cross-sectional area of the jet cooling gas flow.

JP-A-8-340653 Japanese Patent Laid-Open No. 10-178754 JP 2017-184529 A

However, the cooling gas flow in the air gap in the radial flow cooling method is formed by combining the axial flow by the fan and the flow swirling in the circumferential direction by the rotating rotor. Therefore, the flow of the cooling gas in the air gap varies depending on the position in the axial direction.

In the rotor of the rotating electrical machine described in Patent Document 1, a cooling effect can be expected near the center of the rotor where the circumferential component of the flow in the air gap is dominant. However, it is difficult to obtain the expected cooling effect near the air gap entrance where the axial component increases.

Also, as described above, since the flow in the air gap is formed by merging two flows, it cannot be easily predicted. Therefore, in order to obtain the intended effect using the rotor of the rotating electrical machine described in Patent Document 2, it is necessary to accurately predict the direction of the flow in the air gap. Required.

On the other hand, when the flow rate of the cooling gas flowing in the air gap fluctuates due to fan pulsation, drift, or the like, or the flow distribution is biased, there is directivity as described in Patent Document 1 and Patent Document 2. In the structure, a stable ventilation resistance reduction effect may not be obtained.

The present invention has been made to solve the above-described problems, and has a simple structure, obtaining a stable reduction effect of ventilation resistance when cooling gas is ejected from the inside of the rotor to the outside, An object of the present invention is to obtain a rotor and a rotating electrical machine that improve the cooling capacity.

A rotor according to the present invention includes a cylindrical rotor core in which a plurality of axially extending coil slots are provided on an outer peripheral surface, a rotor coil disposed in the coil slot, and an opening of the coil slot. One or more wedge holes that are provided in a portion and fix the rotor coil in the coil slot and allow the cooling gas to flow from the inside of the coil slot to the outside by extending in the radial direction of the rotor core. And at least one of the wedge holes is disposed on a radially outer side of the rotor core than the first portion, and at least one of the wedge holes is a wedge. And a second portion having a second inner diameter larger than the first inner diameter over the entire circumference of the hole.

According to the rotor of the rotating electrical machine according to the present invention, when the cooling gas is ejected from the inside of the rotor to the outside through the wedge hole, the cooling gas is passed through the second portion having a large inner diameter. The cooling gas flow is gently deflected. As a result, it is possible to stably reduce the ventilation resistance when the cooling gas that is jetted collides with the flow of the high-speed cooling gas outside the rotor, so that the air volume of the jetted cooling gas increases, The cooling capacity can be improved.

It is the schematic of the turbine generator to which the rotor of the rotary electric machine which concerns on this invention is applied. It is a fragmentary sectional view of the rotor of the rotary electric machine which concerns on Embodiment 1 of this invention. It is a fragmentary sectional view which shows the wedge vicinity of the rotor which concerns on Embodiment 1 of this invention. It is a figure which shows the wedge of the rotor which concerns on Embodiment 1 of this invention seen from the radial direction outer side of the rotor core. It is a figure which shows the wedge of the rotor which concerns on Embodiment 1 of this invention. It is a figure which shows the circumferential direction flow rate of the cooling gas in an air gap. It is a figure which shows the flow velocity distribution of the cooling gas in an air gap. It is a fragmentary sectional view which shows the wedge vicinity of the common rotor as a comparative example. It is a figure which shows an example of the rotor of the conventional rotary electric machine described in patent document 1. FIG. It is a figure which shows the wedge of patent document 1 seen from the radial direction outer side of the rotor core. It is a figure which shows an example of the rotor of the conventional rotary electric machine described in patent document 2. FIG. It is a figure which shows the wedge of patent document 2 seen from the radial direction outer side of the rotor iron core. 10 is a diagram illustrating an example of a rotor of a conventional rotating electrical machine described in Patent Document 3. FIG. It is a figure which shows the wedge of patent document 3 seen from the radial direction outer side of the rotor core. It is the schematic which shows the turbine generator end part to which the rotor of the rotary electric machine which concerns on this invention is applied. It is a fragmentary sectional view which shows the wedge vicinity of the rotor which concerns on Embodiment 2 of this invention. It is a figure which shows the wedge of the rotor which concerns on Embodiment 2 of this invention seen from the radial direction outer side of the rotor core. It is a figure which shows the 1st modification of the inclined surface which concerns on Embodiment 2 of this invention. It is a fragmentary sectional view which shows the wedge vicinity of the rotor which concerns on Embodiment 3 of this invention. It is a figure which shows the wedge of the rotor which concerns on Embodiment 3 of this invention seen from the radial direction outer side of the rotor core. It is a fragmentary sectional view which shows the wedge vicinity of the rotor which concerns on Embodiment 4 of this invention. It is a figure which shows the wedge of the rotor which concerns on Embodiment 4 of this invention seen from the radial direction outer side of the rotor core. It is a figure which shows the flow of the cooling gas in the air gap in Embodiment 4 of this invention. It is a fragmentary sectional view which shows the wedge vicinity of the rotor which concerns on Embodiment 5 of this invention. It is a figure which shows the wedge of the rotor which concerns on Embodiment 5 of this invention seen from the radial direction outer side of the rotor core. It is a figure which shows the 1st modification of the protruding inclined surface which concerns on Embodiment 5 of this invention. It is a figure which shows the 2nd modification of the protruding inclined surface which concerns on Embodiment 5 of this invention. It is a figure which shows the 3rd modification of the protruding inclined surface which concerns on Embodiment 5 of this invention. It is a figure which shows the 4th modification of the protruding inclined surface which concerns on Embodiment 5 of this invention. It is a figure which shows the flow of the cooling gas in the air gap in Embodiment 5 of this invention.

Hereinafter, preferred embodiments of a rotor of a rotating electrical machine according to the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram of a rotating electrical machine 100 on which a rotor 1 according to Embodiment 1 of the present invention is mounted. The rotating electrical machine 100 of FIG. 1 is a turbine generator, for example. FIG. 2 is a partial cross-sectional view in the radial direction of the rotor 1 according to the first embodiment. Further, FIG. 3 is an enlarged view of the wedge hole 81 portion of the wedge 8 of the rotor 1 according to the first embodiment. FIG. 4 is a diagram illustrating the rotor wedge 8 according to the first embodiment of the present invention as viewed from the radially outer side of the rotor core 2. FIG. 5 is a view showing the wedge 8 of the rotor 1 according to the first embodiment.

As shown in FIG. 1, the rotating electrical machine 100 includes a rotor 1 and a stator 110. Further, the rotating electrical machine 100 includes a cooler 130, two fans 140, and a rotating shaft 150. The stator 110 is formed in a cylindrical shape. The rotor 1 is disposed in the stator 110 such that the inner peripheral surface of the stator 110 faces the outer peripheral surface of the rotor 1. Hereinafter, the inner peripheral surface of the stator 110 is referred to as a stator inner peripheral surface 111, and the outer peripheral surface of the rotor 1 is referred to as a rotor outer peripheral surface 10. There is an air gap between the stator inner peripheral surface 111 and the rotor outer peripheral surface 10, and hereinafter, the air gap will be referred to as an air gap 120. As described above, the stator 110 is disposed via the air gap 120 with respect to the outer periphery of the rotor 1.

The rotor 1 includes a rotor core 2 and a rotor coil 5. The rotor core 2 is fixed to the rotating shaft 150 and rotates by the rotation of the rotating shaft 150. Further, the two fans 140 are respectively fixed to the rotating shaft 150 at the positions of both end portions of the rotor 1. Each fan 140 rotates by the rotation of the rotating shaft 150 to circulate the cooling gas 160 in the rotating electrical machine 100. The arrows in FIG. 1 indicate the flow of the cooling gas 160. The cooler 130 collects and cools the cooling gas 160 that has absorbed the heat of the rotating electrical machine 100. The cooled cooling gas 160 is circulated through the rotating electrical machine 100 again by the fan 140.

A plurality of coil slots 3 extending in the axial direction of the rotor core 2 are provided on the outer peripheral surface of the rotor core 2 constituting the rotor 1. These coil slots 3 are formed at intervals in the circumferential direction of the rotor core 2. FIG. 2 shows only one coil slot 3 among the plurality of coil slots 3. Since each coil slot 3 has the same configuration as that of the coil slot 3 shown in FIG. 2, only one coil slot 3 will be described here.

The coil slot 3 is formed from one end side to the other end side of the rotor core 2 along the axial direction of the rotor core 2. As shown in FIG. 2, the coil slot 3 is a U-shaped recess, and has an opening on the rotor outer peripheral surface 10 side of the rotor core 2. A plurality of rotor coils 5 are stacked in the coil slot 3. These rotor coils 5 are fixed by a wedge 8 fitted in an opening of the coil slot 3 via an insulator 7. As shown in FIGS. 2, 4, and 5, the wedge 8 has at least one wedge hole 81 that penetrates in the radial direction of the rotor core 2 and communicates the inside and the outside of the coil slot 3. Yes. Further, a turn insulator 6 is interposed between the rotor coils 5.

Further, as shown in FIG. 2, each of the plurality of rotor coils 5 and the turn insulator 6 is formed with at least one radial path 9 that penetrates them in the radial direction of the rotor core 2. . Further, the insulator 7 has an insulator hole 71 penetrating in the radial direction of the rotor core 2. The insulator hole 71 communicates with the radial path 9 and also communicates with the wedge hole 81. The wedge hole 81 is composed of, for example, a circular through hole.

Further, a U-shaped channel 4 is formed at the bottom of each coil slot 3. The inside of the channel 4 is a cavity. The channel 4, the radial path 9, the insulator hole 71, and the wedge hole 81 form a ventilation path through which the cooling gas 160 flows. The cooling gas 160 enters each coil slot 3 from the channel 4 and flows into the air gap 120 through the radial path 9, the insulator hole 71, and the wedge hole 81.

In the first embodiment, as shown in FIGS. 2, 3, 4 and 5, the inner diameter of the wedge hole 81 is the first inner diameter and the second inner diameter larger than the first inner diameter. Is included. The second portion 85 having the second inner diameter of the wedge hole 81 is arranged on the outer side in the radial direction of the rotor core 2 than the first portion 86 having the first inner diameter of the wedge hole 81. Hereinafter, the second portion is referred to as a “hole diameter enlarged portion 85”.

In the first embodiment, as shown in FIGS. 2, 3, 4, and 5, a hole diameter enlarged portion 85 is provided at the hole outlet of the wedge hole 81 located on the rotor outer peripheral surface 10 of the rotor 1. ing. The hole diameter enlarged portion 85 is configured by forming an L-shaped stepped portion 85a by providing a L-shaped notch from the hole outlet of the wedge hole 81 to a preset depth ΔH. Has been. The hole diameter enlarged portion 85 is provided evenly over the entire circumference of the wedge hole 81, that is, is configured in an annular shape and has no directivity in the structure. That is, the hole diameter enlarged portion 85 does not have a configuration that intentionally controls the direction of the cooling gas flow 11 in the rotor 1 ejected from the wedge hole 81 toward the air gap 120 in a specific direction. In FIG. 2 and FIG. 3, as can be seen from the fact that the inner wall of the hole diameter expanding portion 85 is shown symmetrically about the central axis of the wedge hole 81, the inner wall of the hole diameter expanding portion 85 is the whole of the wedge hole 81. It is configured to have an axisymmetric shape around the circumference, that is, 360 °, with the central axis of the wedge hole 81 as an axis. In other words, as shown in FIG. 4, when the wedge 8 is viewed from the radially outer side of the rotor core 2, the configuration is symmetrical with respect to the central axis of the wedge hole 81. FIG. 5 shows a part of the wedge 8 alone. Assuming that the inner diameter of the hole diameter expanding portion 85 is the second inner diameter and the inner diameter of the other portion of the wedge hole 81 is the first inner diameter, the second inner diameter is equal to the first step depth of the stepped portion 85a. It is larger than the inner diameter. In the first embodiment, both the first inner diameter and the second inner diameter are constant along the radial direction without gradually increasing or decreasing toward the radially outer side.

As described above, in the first embodiment, with the stepped position of the stepped portion 85a as a boundary, the hole diameter enlarged portion 85 portion is defined as the “second portion having the second inner diameter of the wedge hole 81”, and the wedge. When the portion 86 other than the hole diameter enlarged portion 85 of the hole 81 is a “first portion having the first inner diameter of the wedge hole 81”, the wedge hole 81 has the first portion 86 having the first inner diameter. And a second portion that is disposed radially outside the rotor core 2 relative to the first portion 86 and has a second inner diameter that is larger than the first inner diameter over the entire circumference of the wedge hole 81. Yes.

The viscous cooling gas 160 is accelerated in the circumferential direction of the rotor 1 in the air gap 120 by the wall shearing force of the rotor outer circumferential surface 10 generated by the rotation of the rotor 1, and the circumferential cooling gas flow 121 is generated. Occurs. FIG. 6 shows a circumferential flow velocity distribution of the cooling gas 160 in the air gap 120. The vertical axis represents a dimensionless velocity V / V _{R obtained} by dividing the flow velocity V of the cooling gas 160 in the circumferential direction of the rotor by the circumferential velocity V _R on the outer circumferential surface 10 of the rotor. The horizontal axis represents a dimensionless distance x / L obtained by dividing the distance x in the air gap width direction in the air gap 120 when the stator inner peripheral surface 111 is a reference by the air gap width L. Accordingly, the dimensionless distance x / L of the rotor outer circumferential surface 10 is 1, and the dimensionless distance x / L of the stator inner circumferential surface 111 is 0.

As shown in FIG. 6, the average peripheral velocity of the cooling gas flow 121 of the cooling gas 160 in the circumferential direction of the rotor 1 is outside the region affected by the boundary layer between the rotor outer peripheral surface 10 and the stator inner peripheral surface 111. Is considered to be about ½ of the peripheral velocity of the cooling gas flow 121a on the rotor outer peripheral surface 10.

Further, as shown in FIG. 1, the cooling gas 160 pushed out from the two fans 140 provided at both ends of the rotor 1 flows from the inlet of the air gap 120 and flows in the air gap 120 in the axial direction. The cooling gas flow 121b of the cooling gas 160 is also generated in the axial direction.

The amount and speed of this axial cooling gas flow 121b are determined by the amount of cooling gas 160 flowing from the inlet of the air gap 120 into the air gap 120, the amount of cooling gas 160 flowing from the rotor 1 to the air gap 120, and The amount of cooling gas 160 flowing from the air gap 120 to the stator 110 is determined.

Thus, the cooling gas flow 121 in the air gap 120 is a combination of the axial flow of the rotor 1 and the circumferential flow of the rotor 1, and the cooling gas flow 121 in the air gap 120 is combined. A very sophisticated design is required for accurate prediction.

FIG. 7 illustrates the formed swirl flow, that is, the state of the cooling gas flow 121 in the air gap 120. In the figure, a solid line 122 is a flow velocity distribution viewed from the rotating coordinate system taken on the rotor 1. As described above, the cooling gas flow 121 in the actual air gap 120 is a combination of the axial flow and the circumferential flow, but in FIG. 7, only the flow velocity distribution of the circumferential flow is shown for simplicity. It explains using. In the cooling gas flow 121 in the air gap 120, a turbulent boundary layer having a steep flow velocity gradient develops on the stator inner peripheral surface 111 and the rotor outer peripheral surface 10 as shown in the flow velocity distribution 122. Therefore, the cooling gas flow 11 in the rotor 1 ejected from the wedge hole 81 toward the air gap 120 requires a large amount of energy to break through this boundary layer. In other words, the cooling gas flow 11 in the rotor 1 causes ventilation resistance when ejected.

Here, in order to explain the effect of the first embodiment, as a comparative example, FIG. 8 shows a configuration of a hole outlet portion of a general rotor wedge hole. When the cooling gas in the rotor 1 is discharged from the wedge hole 81 to the air gap 120, it collides with the high-speed cooling gas flow in the air gap 120, thereby causing the inside of the rotor 1 to be discharged from the wedge hole 81. The cooling gas flow 11 is obstructed. As a result, ventilation resistance is generated. Since the rotor 1 rotates at a high speed during rated operation, the cooling gas 160 in the air gap 120 flows at a high speed in the circumferential direction. Therefore, the ventilation resistance in the wedge hole 81 during the rotation of the rotor 1 is increased about three times that when the rotor 1 is stationary. Therefore, in order to keep the temperature of the rotor coil 5 below a certain standard, it is necessary to employ a ventilation fan having a large differential pressure. However, when a ventilating fan with a large differential pressure is employed, the power loss of the fan increases, and there is a problem that the operating efficiency of the rotating electrical machine decreases.

Therefore, in the first embodiment, the hole diameter enlarged portion 85 is provided over the entire circumference of the hole outlet of the wedge hole 81. As described above with reference to FIG. 7, a turbulent boundary layer having a steep flow velocity gradient is formed on the rotor outer peripheral surface 10. At this time, when the hole diameter enlarged portion 85 is provided as in the first embodiment, the cooling gas flow 11 in the rotor 1 collides with the turbulent boundary layer formed on the rotor outer peripheral surface 10. In this case, the cooling gas flow 11 in the rotor 1 can be gently deflected as compared with the case where the hole diameter enlarged portion 85 is not provided. Therefore, the collision angle of the cooling gas flow 11 with the turbulent boundary layer can be reduced. As a result, the energy required when the cooling gas flow 11 is ejected can be reduced. Ventilation resistance when the cooling gas flow 11 in the rotor 1 is ejected into the air gap 120 is reduced. Therefore, in the first embodiment, it is not necessary to employ a fan having a large differential pressure. As a result, fan power loss can be suppressed and the motion efficiency of the rotating electrical machine can be improved.

In the first embodiment, along with the increase in the hole diameter due to the provision of the hole diameter enlargement portion 85, a part of the cooling gas flow 11 in the rotor 1 is peeled off from the hole diameter enlargement portion 85, thereby causing the separation region 124. However, the current spreading loss is insignificant and the ventilation loss is reduced as a whole.

Incidentally, as a conventional technique for mitigating the collision between the cooling gas flow 11 in the rotor 1 and the cooling gas flow 121 in the air gap 120, there is one in which the wedge hole 81 has a directional structure.

As an example of a rotor of a conventional rotating electrical machine having a directional wedge hole, a V-shaped groove 902 is provided on the upstream side of the opening of the wedge hole 81 as shown in FIGS. Some have an inclined surface 903 provided on the downstream side (see, for example, Patent Document 1). In addition, when the said wedge 8 is seen from the radial direction outer side of the rotor core 2, it looks like a structure as shown in FIG.

As apparent from FIG. 10, the wedge 8 of the rotor 1 as described in Patent Document 1 is highly effective when the circumferential component of the flow of the cooling gas 121 in the air gap 120 is dominant. The effect at locations where the axial flow is large, such as the child end, is reduced. Therefore, there is a problem that the effect is changed at a place where the directional wedge hole is applied.

As another example of a rotor of a conventional rotating electric machine having a directional wedge hole, as shown in FIGS. 11 and 12, a protrusion 901 is provided on the upstream side of the opening of the wedge hole 81. Some have an inclined surface 902 on the downstream side (see, for example, Patent Document 2). In addition, when the said wedge 8 is seen from the radial direction outer side of the rotor core 2, it looks like a structure as shown in FIG.

As is clear from FIG. 11, the effect of reducing the ventilation resistance of the wedge hole 81 varies greatly depending on the installation position of the protrusion 901. That is, a large reduction effect can be obtained if the protrusion 901 can be accurately installed on the upstream side of the cooling gas flow 121 in the air gap 120, but the reduction effect cannot be obtained unless the installation position is appropriate. However, as described above, the cooling gas flow 121 in the air gap 120 is a combination of the axial flow of the rotor 1 and the circumferential flow of the rotor 1. Therefore, in order to accurately predict the cooling gas flow 121 in the air gap 120, a very advanced design is required, and it is difficult to obtain the expected reduction effect.

Therefore, the above problem can be avoided by making the wedge hole 81 a non-directional structure. In other words, regardless of the direction of the cooling gas flow 121 in the air gap 120, a constant ventilation resistance reduction effect can be obtained.

As shown in FIGS. 13 and 14, as a rotor of a conventional rotating electrical machine, a tapered portion 905 is provided at a radially outer portion of a ventilation hole 906 provided in a conductor bar 904 inserted in a coil slot of the rotor. Is formed (see, for example, Patent Document 3). In that case, since the taper process is performed on the entire peripheral surface of the vent hole outlet of the conductor bar, a certain effect can be expected no matter which direction the cooling gas flows in the air gap. As shown in FIG. 14, when the wedge 8 is viewed from the outside in the radial direction of the rotor core 2, it appears to have the same configuration as that in FIG. 4. However, when the conductive bar 904 to be energized and heated is tapered, there is a problem that the cross-sectional area of the conductive bar 904 to be energized decreases and the copper loss increases. On the other hand, in Embodiment 1, since processing is performed on the wedge 8 that is not energized and heated, the copper loss is not increased as in the conventional technique described in Patent Document 3.

By the way, when the fan 140 pulsates, the flow rate of the cooling gas 160 in each part of the rotating electrical machine 100 varies. As a matter of course, the flow rate of the air gap 120 also varies. In such a case, when the wedge hole 81 has a directional structure, the ventilation resistance reduction effect of the wedge hole 81 also varies in accordance with the variation of the cooling gas 160 in the air gap 120. On the other hand, when the structure in which the wedge hole 81 has no directivity and can reduce the ventilation resistance is applied to the wedge hole 81 as in the first embodiment, the stable wedge hole 81 regardless of the pulsation of the fan 140. Can be expected to reduce the ventilation resistance.

Also, when a drift occurs in the fan 140, the flow distribution of the cooling gas 160 in the air gap 120 may be biased. For example, as shown in FIG. 15, when the cooler 130 is installed only on the upper side of the rotating electrical machine 100, the cooling gas 160 is sucked from the upper side of the fan 140 and tends to be pushed downward. As a result, the flow rate distribution of the cooling gas 160 when flowing into the air gap 120 is uneven in the circumferential direction. In such a case, when the wedge hole 81 has a directional structure, the air flow resistance reduction effect of the wedge hole 81 also varies in accordance with the bias of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the first embodiment, the ventilation resistance of the wedge hole 81 is stably reduced regardless of the drift of the fan 140. The effect can be expected.

By the way, during operation of the rotating electrical machine 100, a local high temperature portion may be generated in the rotor coil 5 due to an uneven flow distribution of the cooling gas 160 to each radial path 9. Hereinafter, this local high-temperature portion is referred to as a hot spot. When a hot spot is generated, there may be a case where a rotating shaft is shaken due to poor insulation of the rotating electrical machine 100 or thermal deformation of the rotor 1. As a result, there is a possibility that the rotating electrical machine 100 will eventually be damaged. Therefore, in the prior art, the diameter of the wedge hole 81 communicated with the radial path 9 in advance, which may cause the flow rate of the cooling gas 160 to be insufficient, is wider than that of the wedge hole 81 communicated with the other radial path 9. In addition, the diameter of the wedge hole 81 communicated with the radial path 9 in which the flow rate of the cooling gas 160 may become excessive is made smaller than that of the wedge hole 81 communicated with the other radial path 9. The flow distribution of the cooling gas 160 supplied to each radial path 9 is adjusted.

In the first embodiment, the hole diameter enlarged portion 85 is provided only for the wedge hole 81 communicated with the radial path 9 where the flow rate of the cooling gas 160 may be insufficient in advance. In that case, the flow rate of the cooling gas 160 supplied to the radial path 9 provided with the hole diameter enlarged portion 85 can be increased. As a result, the generation of hot spots can be suppressed and the rotor coil 5 can be cooled uniformly.

Alternatively, by applying the conventional technique for adjusting the hole diameter of each wedge hole 81 and the first embodiment to the rotating electrical machine 100, not only can the cooling capacity of the rotor 1 be improved, but also more uniform than in the past. Can be cooled.

According to the rotor 1 of the first embodiment configured as described above, a plurality of coil slots 3 extending in the axial direction are formed in the rotor core 2, and a channel 4 is formed in each coil slot 3. Yes. In each coil slot 3, a plurality of rotor coils 5 and turn insulators 6 are stacked and fixed with wedges 8 via insulators 7. Furthermore, at least one radial path 9 that penetrates the plurality of rotor coils 5 and the turn insulator 6 in the radial direction and communicates with the channel 4 is formed. The insulator 7 and the wedge 8 are formed with an insulator hole 71 and a wedge hole 81 that communicate with at least one of the radial paths 9 and open to the outer peripheral side. The channel 4, at least one radial path 9, the insulator hole 71 formed in the insulator 7 and the wedge 8, and the wedge hole 81 form an air passage for the cooling gas 160. Further, a hole diameter expanding portion 85 is provided at a hole outlet located on the outer side in the radial direction of the rotor 1 of the wedge hole 81 formed in the wedge 8.

Thereby, according to the rotor 1 of Embodiment 1, the ventilation resistance of the rotor 1 of the rotary electric machine 100 is stably reduced by using a simple structure without increasing the copper loss of the rotor coil 5. The cooling capacity of the rotor 1 can be further improved.

Embodiment 2. FIG.
A wedge hole 81 provided in the rotor 1 according to the second embodiment of the present invention will be described with reference to FIGS. 16 and 17. FIG. 16 is a partial cross-sectional view showing a wedge 8 portion of rotor 1 according to Embodiment 2 of the present invention. FIG. 17 is a view showing the wedge 8 of the rotor 1 according to the second embodiment of the present invention as seen from the radially outer side of the rotor core 2.

As shown in FIG. 16, in the second embodiment, the wedge diameter 81 of the rotor 1 is provided with a hole diameter expanding portion 82 constituted by an inclined surface 82 a. While the hole diameter of the hole diameter expanding portion 85 according to the first embodiment is constant along the radial direction, the inner diameter of the hole diameter expanding section 82 according to the second embodiment, that is, the second inner diameter is It is different from the first embodiment in that it increases continuously outward in the radial direction. Other configurations are the same as those in the first embodiment.

In the second embodiment, as shown in FIG. 16, the inner portion of the tip of the hole outlet of the wedge hole 81 of the rotor 1 is an inclined surface 82a. That is, the shape of the hole outlet of the wedge hole 81 is a reverse taper shape, and the opening portion has the largest inner diameter.

As described above, in the second embodiment, the wedge hole 81 of the rotor 1 is provided with the hole diameter enlarged portion 82 formed of the inclined surface 82a. As described above, the hole diameter expanding portion 82 may be configured from the curved surface 82b instead of the inclined surface 82a. Also in the case of the curved surface 82b, the inner diameter of the hole diameter enlarged portion 82 continuously increases toward the outer side in the radial direction of the rotor 1, similarly to the inclined surface 82a.

In FIGS. 16 and 18, as can be seen from the fact that the inner wall of the hole diameter expanding portion 82 is shown symmetrically about the central axis of the wedge hole 81, the inner wall of the hole diameter expanding portion 82 is the wedge hole 81. Is formed so as to have an axisymmetric shape about the central axis of the wedge hole 81 over the entire circumference, that is, 360 °. Therefore, also in the second embodiment, the structure of the wedge hole 81 does not have directivity. Note that, when the wedge 8 is viewed from the outside in the radial direction of the rotor core 2, it looks as shown in FIG. 17.

As described above, in the second embodiment, the hole diameter enlarged portion 82 formed of the inclined surface 82a or the curved surface 82b is provided over the entire circumference of the wedge hole 81. Therefore, when the cooling gas flow 11 in the rotor 1 collides with the turbulent boundary layer formed on the rotor outer peripheral surface 10, the cooling gas flow 11 in the rotor 1 follows the inclined surface 82a or the curved surface 82b. Gently deflect. Thereby, the energy required when the cooling gas flow 11 is ejected can be reduced. That is, by providing the inclined surface 82a or the curved surface 82b over the entire circumference of the hole outlet of the wedge hole 81, the ventilation resistance when the cooling gas flow 11 in the rotor 1 is ejected into the air gap 120 is suppressed.

At this time, in the second embodiment, by providing the wedge hole 81 with the inclined surface 82a or the curved surface 82b, the separation region 124 generated when the cooling gas flow 11 in the rotor 1 passes through the hole diameter enlarged portion 82 is provided. Since it can be reduced as compared with the first embodiment, a higher ventilation resistance reduction effect than that of the first embodiment can be expected.

In addition, this reduction effect is higher when the curved surface 82b is provided than when the inclined surface 82a is provided in the wedge hole 81.

Also in the second embodiment, since the structure of the wedge hole 81 does not have directivity, a constant ventilation resistance reduction effect can be expected regardless of the direction of the cooling gas flow 121 in the air gap 120. Therefore, unlike the prior art such as Patent Document 2, for example, it is not necessary to predict the cooling gas flow 121 in the air gap 120, and the rotor 1 with improved cooling performance can be obtained more easily.

Further, since the wedge 8 that is not energized and heated is processed, there is no increase in copper loss unlike the prior art described in Patent Document 3.

By the way, when the fan 140 pulsates, the flow rate of the cooling gas 160 in each part of the rotating electrical machine 100 varies. As a matter of course, the flow rate of the air gap 120 also varies. At this time, when the wedge hole 81 has a directional structure, the ventilation resistance reduction effect of the wedge hole 81 also varies in accordance with the variation of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the second embodiment, the stable ventilation of the wedge hole 81 regardless of the pulsation of the fan 140. A resistance reduction effect can be expected.

Also, when a drift occurs in the fan 140, the flow distribution of the cooling gas 160 in the air gap 120 may be biased. In such a case, when the wedge hole 81 has a directional structure, the air flow resistance reduction effect of the wedge hole 81 also varies in accordance with the bias of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the second embodiment, the stable ventilation of the wedge hole 81 regardless of the drift of the fan 140. A resistance reduction effect can be expected.

Furthermore, the hole diameter enlarged portion 82 of the second embodiment may be applied only to the wedge hole 81 communicated with the radial path 9 where the flow rate of the cooling gas 160 may be insufficient in advance. In that case, the flow rate of the cooling gas 160 supplied to the applied radial path 9 can be increased, generation of hot spots can be suppressed, and the rotor coil 5 can be cooled uniformly.

Then, by applying the conventional technique for adjusting the hole diameter of the individual wedge holes 81 described above and the second embodiment to the rotating electrical machine 100, not only the cooling capacity of the rotor 1 can be improved but also more uniform than the conventional one. You can expect to cool down.

In the second embodiment, the hole diameter enlarged portion 82 is defined as “a second portion having the second inner diameter of the wedge hole 81” with the position where the inclined surface 82 a or the curved surface 82 b starts as a boundary. When the portion other than the hole diameter enlarged portion 82 is a “first portion having the first inner diameter of the wedge hole 81”, in the second embodiment as well, the wedge hole 81 is similar to the first embodiment. A first portion having a first inner diameter; and a second portion having a second inner diameter larger than the first inner diameter, which is disposed radially outside the rotor core 2 relative to the first portion. doing.

Thereby, according to the wedge 8 of the rotor 1 according to the second embodiment, the ventilation resistance of the rotor 1 of the rotating electrical machine 100 is reduced without increasing the copper loss of the rotor coil 5 using a simple structure. And the cooling capacity of the rotor 1 can be further improved.

Embodiment 3 FIG.
A wedge hole 81 provided in the rotor 1 according to the third embodiment of the present invention will be described with reference to FIGS. 19 and 20. FIG. 19 is a partial cross-sectional view showing a wedge 8 portion of rotor 1 according to Embodiment 3 of the present invention. FIG. 20 is a diagram illustrating the wedge 8 of the rotor 1 according to the third embodiment of the present invention as viewed from the radially outer side of the rotor core 2.

As shown in FIG. 19, the third embodiment is different from the first and second embodiments in that a groove 86 is formed on the surface of the wedge 8 with respect to the wedge hole 81 of the rotor 1. . Other configurations are the same as those in the first and second embodiments.

In FIG. 19, as can be seen from the fact that the groove 86 is shown symmetrically about the central axis of the wedge hole 81, the groove 86 is wedge-shaped over the entire circumference of the wedge hole 81, ie, 360 °. The hole 81 is configured to be axisymmetric about the central axis. Therefore, also in the third embodiment, the structure of the wedge hole 81 does not have directivity. In addition, when the said wedge 8 is seen from the radial direction outer side of the rotor core 2, it looks like a structure as shown in FIG.

At this time, in the third embodiment, the groove 86 is provided in the wedge hole 81 so that the cooling gas flow 121 in the air gap 120 collides with the cooling gas flow 11 in the rotor ejected from the wedge hole 81. Before it is deflected, it is deflected by the groove 86. Therefore, the collision angle between the cooling gas flow 121 in the air gap 120 and the cooling gas flow 11 in the rotor ejected from the wedge hole 81 is equal to the amount by which the cooling gas flow 121 in the air gap 120 is deflected by the groove 86. , Get even bigger. As a result, it is possible to expect a higher ventilation resistance reduction effect than in the first and second embodiments.

Also in the third embodiment, since the structure of the wedge hole 81 does not have directivity, a constant ventilation resistance reduction effect can be expected regardless of the direction of the cooling gas flow 121 in the air gap 120. Therefore, unlike the prior art such as Patent Document 2, for example, it is not necessary to predict the cooling gas flow 121 in the air gap 120, and the rotor 1 with improved cooling performance can be obtained more easily.

By the way, when the fan 140 pulsates, the flow rate of the cooling gas 160 in each part of the rotating electrical machine 100 varies. As a matter of course, the flow rate of the air gap 120 also varies. At this time, when the wedge hole 81 has a directional structure, the ventilation resistance reduction effect of the wedge hole 81 also varies in accordance with the variation of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the third embodiment, the stable ventilation of the wedge hole 81 regardless of the pulsation of the fan 140. A resistance reduction effect can be expected.

Then, by applying the conventional technique for adjusting the hole diameter of the individual wedge holes 81 described above and the third embodiment to the rotating electrical machine 100, not only the cooling capacity of the rotor 1 can be improved but also more uniform than the conventional one. You can expect to cool down.

Thereby, according to the wedge 8 of the rotor 1 according to the third embodiment, the ventilation resistance of the rotor 1 of the rotating electrical machine 100 is reduced without increasing the copper loss of the rotor coil 5 using a simple structure. The cooling capacity of the rotor 1 can be further improved.

Embodiment 4 FIG.
A wedge hole 81 constituting the rotor 1 according to the fourth embodiment of the present invention will be described with reference to FIGS. FIG. 21 is a partial cross-sectional view showing wedge 8 of rotor 1 according to the fourth embodiment of the present invention. FIG. 22 is a view showing the wedge 8 of the rotor 1 according to the fourth embodiment of the present invention as seen from the radially outer side of the rotor core 2. The fourth embodiment is different from the first to third embodiments in that the wedge hole 81 has a protruding edge composed of a protrusion 83a. In the fourth embodiment, the hole diameter enlarged portion 83 as the second portion having the second inner diameter is configured by the protruding edge. Other configurations are the same as those in the first to third embodiments.

In the fourth embodiment, as shown in FIG. 21, a protrusion 83a is formed over the entire circumference of the hole outlet of the wedge hole 81 located on the outer side in the radial direction of the rotor 1, thereby forming a protruding edge of the wedge hole 81. Has been. As shown in FIG. 21, the protrusion 83 a is provided so as to protrude from the rotor outer peripheral surface 10 of the rotor core 2. The protruding edge formed of the protrusion 83a has a short cylindrical shape, and the wall thickness is constant over the entire circumference. In the fourth embodiment, a portion surrounded by the protrusion 83a is referred to as a hole diameter enlarged portion 83. Here, as shown in FIG. 21, since the protrusion 83a is provided in a portion outside the outlet hole of the wedge hole 81, the inner diameter of the hole diameter enlarged portion 83 formed of the protrusion 83a, that is, the second The inner diameter is larger than the inner diameter of the other part over the entire circumference of the wedge hole 81, that is, the first inner diameter.

In FIG. 21, the inner wall and the outer wall of the hole diameter expanding portion 83 are shown symmetrically about the central axis of the wedge hole 81, so that the inner wall and the outer wall of the hole diameter expanding portion 83 are wedge holes. The entire circumference of 81, that is, 360 °, is configured to be axisymmetric with respect to the central axis of the wedge hole 81. Therefore, also in the fourth embodiment, the structure of the wedge hole 81 does not have directivity. Note that, when the wedge 8 is viewed from the outside in the radial direction of the rotor core 2, it looks as shown in FIG.

As described above, in the fourth embodiment, the hole diameter enlarged portion 83 surrounded by the protrusion 83a is referred to as a “second portion having the second inner diameter of the wedge hole 81”, and other than the hole diameter enlarged portion 83 of the wedge hole 81. When the other part is defined as “a first part having the first inner diameter of the wedge hole 81”, in the fourth embodiment as well, the wedge hole 81 has the first inner diameter as in the first embodiment. And a second portion having a second inner diameter that is larger than the first inner diameter and is disposed on the outer side in the radial direction of the rotor core 2 than the first portion.

In the fourth embodiment, the projection 83a is provided over the entire circumference of the hole outlet of the wedge hole 81 located on the radially outer side of the rotor 1, so that the cooling gas flow 121 in the air gap 120 is ejected from the wedge hole 81. Before colliding with the cooling gas flow 11 in the rotor, a part is separated by colliding with the protrusion 83 a, and a separation region is formed around the wedge hole 81.

FIG. 23 illustrates the state of the cooling gas flow 121 in the air gap 120 when the protrusion 83a is provided over the entire circumference of the hole outlet of the wedge hole 81 located on the radially outer side of the rotor 1. . In FIG. 23, a solid line 122 is a flow velocity distribution viewed from the rotating coordinate system taken on the rotor 1. As described above, the cooling gas flow 121 in the actual air gap 120 is a combination of the axial flow and the circumferential flow. However, for the sake of simplicity, FIG. 23 will be described using the flow velocity distribution of the circumferential flow.

23, the cooling gas flow 121 in the air gap 120 collides with the protrusion 83a and is deflected above the protrusion 83a, that is, in the outer diameter direction of the rotor core 2. As shown in FIG. Furthermore, after the cooling gas flow 121 reaches the upper end of the protrusion 83a, a part thereof is peeled off. Along with this peeling phenomenon, the flow velocity distribution downstream of the protrusion 83a causes a reverse flow like the flow velocity distribution of FIG. 23, and a dead water region 123 is formed. The speed of the cooling gas flow 121 in the dead water region 123 is slightly smaller than the speed of the main flow of the cooling gas flow 121 in the air gap 120. Moreover, the static pressure in the dead water area | region 123 is low. That is, the stronger the turbulent shear layer, the greater the energy required to break it and eject the fluid, so that the cooling gas flow 11 is ejected to the dead water region 123 formed by the protrusion 83a. Clearly, a small amount of energy is sufficient.

In the fourth embodiment, the protrusion 83a is provided over the entire circumference of the hole outlet of the wedge hole 81 located on the rotor outer peripheral surface 10. As a result, the cooling gas flow 121 in the air gap 120 collides with the protrusion 83 a before colliding with the cooling gas flow 11 in the rotor 1 ejected from the wedge hole 81 of the rotor 1. As a result, the airflow resistance when the cooling gas flow 11 in the rotor 1 passes through the wedge hole 81 and is discharged to the air gap 120 can be suppressed.

Further, as can be seen from FIG. 21, the height of the projection 83a is sufficiently smaller than the width of the air gap 120, so the ventilation resistance associated with passing through the projection 83a is small. Therefore, the increase in ventilation resistance due to the collision of the cooling gas flow 11 in the rotor 1 ejected from the wedge hole 81 with the protrusion 83a downstream of the wedge hole 81 is slight, and the ventilation resistance is reduced as a whole. The

Further, when the protrusion 83a located on the downstream side is installed so as to be accommodated in the dead water region 123, the ventilation resistance when the cooling gas flow 121 in the air gap 120 collides with the protrusion 83a on the downstream side is within the air gap 120. Therefore, the rotor 1 of the rotating electrical machine 100 having higher cooling capacity can be obtained.

Also in the fourth embodiment of the present invention, as in the first and second embodiments, the structure of the wedge hole 81 does not have directivity, so the cooling gas flow 121 in the air gap 120 flows from any direction. A certain reduction effect of ventilation resistance can be expected. Therefore, unlike the prior art of Patent Document 2, there is no need to predict the cooling gas flow 121 in the air gap 120, and the cooling performance of the rotor 1 can be improved more easily.

Further, since the wedge 8 that is not energized and heated is processed, the copper loss is not increased unlike the technique described in Patent Document 3.

By the way, when the fan 140 pulsates, the flow rate of the cooling gas 160 in each part of the rotating electrical machine 100 varies. As a matter of course, the flow rate of the air gap 120 also varies. In such a case, when the wedge hole 81 has a directional structure, the ventilation resistance reduction effect of the wedge hole 81 also varies in accordance with the variation of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing ventilation resistance is applied to the wedge hole 81 as in the fourth embodiment, the stable ventilation of the wedge hole 81 regardless of the pulsation of the fan 140. A resistance reduction effect can be expected.

Also, when a drift occurs in the fan 140, the flow distribution of the cooling gas 160 in the air gap 120 may be biased. In such a case, when the wedge hole 81 has a directional structure, the air flow resistance reduction effect of the wedge hole 81 also varies in accordance with the bias of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the fourth embodiment, the stable ventilation of the wedge hole 81 regardless of the drift of the fan 140. A resistance reduction effect can be expected.

Furthermore, if the projection 83a of the fourth embodiment is applied only to the wedge hole 81 communicated with the radial path 9 where the flow rate of the cooling gas 160 may be insufficient in advance, the applied radial path 9 can be applied. The flow rate of the supplied cooling gas 160 can be increased, generation of hot spots can be suppressed, and the rotor coil 5 can be cooled uniformly.

Then, by applying the conventional technique for adjusting the diameter of each wedge hole 81 and the protrusion 83a of the fourth embodiment to the rotating electrical machine 100, not only can the cooling capacity of the rotor 1 be improved, but also the conventional technique. Can be expected to cool evenly.

Thus, according to the wedge 8 of the rotor 1 according to the fourth embodiment, the ventilation resistance of the rotor 1 of the rotating electrical machine 100 is reduced without increasing the copper loss of the rotor coil 5 using a simple structure. The cooling capacity of the rotor 1 can be further improved.

In the fourth embodiment, the degree of the effect varies depending on how the second inner diameter of the wedge hole 81 is expanded. For example, the ratio of the second inner diameter with respect to the first inner diameter is set to be the expansion of the second inner diameter of the wedge hole 81, and the ratio of the second inner diameter with respect to the first inner diameter is preferably about 1.6 times or less.

Embodiment 5. FIG.
A wedge hole 81 constituting the rotor 1 according to the fifth embodiment will be described with reference to FIGS. FIG. 24 is a partial cross-sectional view showing a wedge 8 portion of rotor 1 according to the fifth embodiment of the present invention. FIG. 25 is a view showing the wedge 8 of the rotor 1 according to the fifth embodiment of the present invention as viewed from the radially outer side of the rotor core 2. As shown in FIG. 24, in the fifth embodiment, an inclined surface that protrudes outward from the rotor outer peripheral surface 10 over the entire circumference of the hole outlet of the wedge hole 81 located on the radially outer side of the rotor 1. The difference from Embodiments 1 to 4 is that 84a is applied. Other configurations are the same as those in the first to fourth embodiments.

In the fifth embodiment, as shown in FIG. 24, an inclined surface 84a is provided over the entire circumference of the hole outlet of the wedge hole 81 located on the radially outer side of the rotor 1. In the fifth embodiment, a part of the inclined surface 84a protrudes from the outer circumferential surface 10 of the rotor, so that the wedge hole 81 has a projecting edge constituted by a protrusion. Is different. That is, in the fourth embodiment, a part of the hole diameter enlarged portion 83 as the second part having the second inner diameter is configured by the protruding edge. Hereinafter, a portion surrounded by the inclined surface 84a is referred to as a hole diameter enlarged portion 84.

As a manufacturing method of the hole diameter enlarged portion 84, for example, the thickness of a general wedge 8 as shown in FIG. 8 is increased by a preset thickness. In that case, the tip of the wedge 8 protrudes from the rotor outer peripheral surface 10 toward the radially outer side of the rotor by the thickness. At this time, the inclined surface 84a can be formed by forming the inner surface at the tip of the wedge 8 to be an inclined surface having a certain angle. Moreover, the hole diameter enlarged part 84 can be formed by forming similarly in an outer surface.

As described above, in the fifth embodiment, the hole diameter enlarged portion 84 surrounded by the inclined surface 84 a is referred to as a “second portion having the second inner diameter of the wedge hole 81”, and the hole diameter enlarged portion 84 of the wedge hole 81. When the other portion than “the first portion having the first inner diameter of the wedge hole 81” is used, the wedge hole 81 is similar to the first portion having the first inner diameter, as in the first embodiment. And a second portion having a second inner diameter larger than the first inner diameter over the entire circumference of the wedge hole 81, which is disposed on the radially outer side of the rotor core 2 with respect to the first portion.

It should be noted that the shape of the inner surface at the tip of the wedge 8 is not limited to the inclined surface 84a shown in FIG. 24, and may be a curved surface 84b as shown in FIG.

Further, as shown in FIG. 24, the outer surface of the protruding portion of the hole diameter enlarged portion 84 does not need to be perpendicular to the rotor outer peripheral surface 10, and is, for example, an inclined surface 84c as shown in FIG. May be. As shown in FIG. 27, the inclined surface 84 c is inclined at a certain angle from the apex of the inclined surface 84 a toward the rotor outer peripheral surface 10. At this time, since the inclined surface 84c is inclined toward the opposite side to the inclined surface 84a, the portion formed by the two

inclined surfaces

84a and 84c has a mountain shape as shown in FIG. . 27 shows an example in which the inclined surface 84c is provided for the configuration of FIG. 24, while FIG. 28 shows an example in which the inclined surface 84c is provided for the configuration of FIG. As shown in FIG. 28, the outer surface of the hole diameter enlarged portion 84 formed from the curved surface 84b may be configured from an inclined surface 84c.

Further, as shown in FIG. 29, a groove 86 may be provided on the outer surface of the protruding portion of the hole diameter expanding portion 84.

24 to 28, as can be seen from the fact that the inner wall and the outer wall of the hole diameter expanding portion 84 are shown symmetrically about the central axis of the wedge hole 81, the inner wall and the outer wall of the hole diameter expanding portion 84 are The entire circumference of the wedge hole 81, that is, 360 °, is configured to have an axisymmetric shape with the central axis of the wedge hole 81 as an axis. Therefore, also in the fifth embodiment, the structure of the wedge hole 81 does not have directivity. In addition, when the wedge 8 is seen from the radial direction outer side of the rotor core 2, it looks like a structure as shown in FIG.

Also in FIG. 29, as can be seen from the fact that the inner wall and outer wall of the enlarged diameter portion 84 and the groove 86 are shown symmetrically about the central axis of the wedge hole 81, the inner wall and the outer wall of the enlarged diameter portion 84 are The entire circumference of the wedge hole 81, that is, 360 °, is configured to have an axisymmetric shape with the central axis of the wedge hole 81 as an axis. Therefore, also in the fifth embodiment, the structure of the wedge hole 81 does not have directivity.

FIG. 30 shows the rotation of the rotor 1 when the hole diameter enlarged portion 84 protruding from the rotor outer peripheral surface 10 is provided over the entire circumference of the hole outlet of the wedge hole 81 located on the radially outer side of the rotor 1. It is a flow velocity distribution figure seen from a coordinate system. As described above, the cooling gas flow 121 in the actual air gap 120 is a combination of the axial flow and the circumferential flow. In FIG. 30, for the sake of simplicity, description will be made using only the flow velocity distribution of the circumferential flow. By providing the hole diameter enlarged portion 84 protruding over the entire circumference of the hole outlet of each wedge hole 81, the cooling gas flow 121 in the air gap 120 is as follows, as in the case of the fourth embodiment. That is, the cooling gas flow 121 collides with the outer surface of the projecting hole diameter enlarged portion 84 before colliding with the cooling gas flow 11 in the rotor ejected from the wedge hole 81. As a result, a dead water region 123 is formed around the wedge hole 81. Due to the decrease in static pressure accompanying the formation of the dead water region 123, the ventilation resistance when the cooling gas flow 11 in the rotor 1 passes through the wedge hole 81 decreases. Further, since the inclined surface 84a or the curved surface 84b is provided inside the wedge hole 81, the collision angle with the cooling gas flow 121 in the air gap 120 can be relaxed, and an even higher ventilation resistance reduction effect can be expected.

Since the structure of the wedge hole 81 according to the fifth embodiment does not have directivity, a constant ventilation resistance reduction effect can be expected regardless of the direction of the cooling gas flow 121 in the air gap 120. Therefore, unlike the prior art of Patent Document 2, there is no need to predict the cooling gas flow 121 in the air gap 120, and the cooling performance of the rotor 1 can be improved more easily.

By the way, when the fan 140 pulsates, the flow rate of the cooling gas 160 in each part of the rotating electrical machine 100 varies. As a matter of course, the flow rate of the air gap 120 also varies. In such a case, when the wedge hole 81 has a directional structure, the ventilation resistance reduction effect of the wedge hole 81 also varies in accordance with the variation of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and capable of reducing the ventilation resistance is applied to the wedge hole 81 as in the fifth embodiment, the stable ventilation of the wedge hole 81 regardless of the pulsation of the fan 140. A resistance reduction effect can be expected.

Also, when a drift occurs in the fan 140, the flow distribution of the cooling gas 160 in the air gap 120 may be biased. In such a case, when the wedge hole 81 has a directional structure, the air flow resistance reduction effect of the wedge hole 81 also varies in accordance with the bias of the cooling gas 160 in the air gap 120. On the other hand, when the structure having no directivity and reducing the ventilation resistance is applied to the wedge hole 81 as in the fifth embodiment, the stable ventilation of the wedge hole 81 regardless of the drift of the fan 140. A resistance reduction effect can be expected.

Furthermore, if the hole diameter enlarged portion 84 of the fifth embodiment is applied only to the wedge hole 81 communicated with the radial path 9 where the flow rate of the cooling gas 160 may be insufficient in advance, the applied radial path is applied. 9 can increase the flow rate of the cooling gas 160, suppress the occurrence of hot spots, and cool the rotor coil 5 uniformly.

Then, by applying the conventional technique for adjusting the hole diameter of each wedge hole 81 and the fifth embodiment of the present invention to the rotating electrical machine 100, not only can the cooling capacity of the rotor 1 be improved, but also more uniform than in the past. You can expect to cool down.

Thereby, according to the wedge 8 of the rotor 1 according to the fifth embodiment, the ventilation resistance of the rotor 1 of the rotating electrical machine 100 is reduced without increasing the copper loss of the rotor coil 5 using a simple structure. And the cooling capacity of the rotor 1 can be further improved.

Note that, also in the fifth embodiment, the degree of the effect varies depending on how the second inner diameter of the wedge hole 81 is expanded, as in the fourth embodiment. For example, the ratio of the second inner diameter with respect to the first inner diameter is set to be the expansion of the second inner diameter of the wedge hole 81, and the ratio of the second inner diameter with respect to the first inner diameter is preferably about 1.6 times or less.

The above Embodiments 1 to 5 show some embodiments of the present invention, and the present invention is not limited thereto. The present invention can be appropriately modified and omitted within the scope of the invention. Further, the present invention does not depend on the type of the cooling gas 160.

1 Rotor, 2 Rotor Core, 3 Coil Slot, 4 Channels, 5 Rotor Coil, 6 Turn Insulator, 7 Insulator, 8 Wedge, 9 Radial Pass, 10 Rotor Outer Surface, 11 Cooling Gas Flow, 71 Insulation Object hole, 81 wedge hole, 82, 83, 84, 85 groove, 86 hole diameter enlarged part, 82a inclined surface, 82b curved surface, 83a protrusion, 84a inclined surface, 84b curved surface, 84c inclined surface, 100 rotating electrical machine, 110 stator, 111 Stator inner peripheral surface, 120 air gap, 121 cooling gas flow, 122 cooling gas flow velocity distribution, 123 dead water region, 124 peeling region, 130 cooler, 140 fan, 150 rotating shaft, 160 cooling gas, 901 protrusion, 902 903 inclined surface, 904 conductor bar, 905 taper, 90 Ventilation holes.

Claims

A cylindrical rotor core provided with a plurality of axially extending coil slots on the outer peripheral surface;
A rotor coil disposed in the coil slot;
1 provided in the opening of the coil slot, for fixing the rotor coil in the coil slot, and extending the radial direction of the rotor core to allow cooling gas to flow from the inside of the coil slot to the outside. A wedge having the above wedge holes, and
At least one of the wedge holes is
A first portion having a first inner diameter;
It is arranged on the outer side in the radial direction of the rotor core than the first part,
A second portion having a second inner diameter greater than the first inner diameter over the entire circumference of the wedge hole;
Rotor.
The first inner diameter is constant along the radial direction of the rotor core.
The rotor according to claim 1.
The second inner diameter is constant along the radial direction of the rotor core.
The rotor according to claim 1 or 2.
The second inner diameter continuously increases toward the radially outer side of the rotor core.
The rotor according to claim 1 or 2.
The at least one of the wedge holes is
Having a groove on the wedge surface radially outside the wedge hole,
The rotor according to any one of claims 1 to 4.
The at least one of the wedge holes has a protruding edge protruding from the outer peripheral surface of the rotor core;
All or part of the second part is constituted by the protruding edge,
The rotor according to any one of claims 1 to 5.
The inner wall of the second portion is configured to have an axisymmetric shape around the central axis of the wedge hole over the entire circumference of the wedge hole.
The rotor according to any one of claims 1 to 6.
The rotor according to any one of claims 1 to 7,
A rotating electrical machine comprising: a stator disposed through a gap with respect to the outer periphery of the rotor.