WO2023037411A1 - Stator for dynamoelectric machine and dynamoelectric machine - Google Patents

Abstract

This stator for a dynamoelectric machine stator comprises a stator core having slots, a flat wire coil arranged through the slots, and a resin member arranged filled in the slots together with the flat wire coil. The flat wire coil has a conductor that has a flat wire form, and insulating projections arranged on the circumferential surface of the conductor.

Description

Rotating electric machine stator and rotating electric machine

The present invention relates to a rotating electrical machine stator and rotating electrical machine, and more particularly to a rotating electrical machine stator and rotating electrical machine capable of improving heat dissipation.

In general, in a stator using flat wire coils, a U-shaped flat wire coil having an insulating coating is inserted into slots of a stator core in which insulating paper is inserted, and flat wire coils protruding from the slots are inserted into the slots of the stator core. The rectangular wire coil is connected by joining the ends of the wire coil.

Conventionally, when a coil is inserted into a slot of a stator core, an insulating resin bobbin is inserted into the slot to ensure the insulation of the coil while avoiding damage to the coil. A stator for a motor has been proposed (see Patent Document 1).

WO2020/017133

However, since the insulating resin bobbin as described in Patent Document 1 needs to be inserted into the slot, it requires a certain degree of mechanical strength, and there is a limit to how thin it can be made. Further, when such an insulating resin bobbin is used, a gap is generated between the inner wall of the slot and the insulating resin bobbin, and between the insulating resin bobbin and the coil to be inserted into the insulating resin bobbin. Therefore, there is a problem that it is difficult to further improve the heat dissipation performance of the rotating electric machine stator as described in Patent Document 1 due to the thinness limit of the insulating resin bobbin and the occurrence of these gaps.

The present invention has been made in view of such problems of the conventional technology, and an object of the present invention is to provide a stator for a rotating electrical machine and a rotating electrical machine that can improve heat dissipation.

The inventors of the present invention have made extensive studies to achieve the above object, and as a result, the above object has been achieved by providing a rectangular wire coil having a conductor having a rectangular wire shape and insulating projections provided on the peripheral surface of the conductor. I found that it can be done, and came to complete the present invention.

That is, the stator for a rotating electric machine of the present invention includes a stator core having a slot, a rectangular wire coil disposed through the slot, and a resin material filled in the slot together with the rectangular wire coil. This rectangular wire coil has a conductor having a rectangular wire shape and insulating projections provided on the peripheral surface of the conductor.

Further, the rotating electrical machine of the present invention includes a rotating electrical machine stator and a rotating electrical machine rotor. This stator for a rotating electrical machine is the stator for a rotating electrical machine according to the present invention.

According to the present invention, it is possible to provide a stator for a rotating electrical machine and a rotating electrical machine that can improve heat dissipation, since it has a conductor having a rectangular wire shape and a rectangular wire coil having insulating projections installed on the peripheral surface of the conductor.

1 is a perspective view showing a main part of an embodiment of a rotating electric machine of the present invention; FIG. FIG. 2 is a partial cross-sectional view of a slot portion of a stator used in the rotating electrical machine shown in FIG. 1 taken perpendicularly to the axial direction of the stator; FIG. 2 is a partial cross-sectional view of a slot portion of a stator used in the rotating electrical machine of FIG. 1 cut along the circumferential direction of the stator; 1 is a perspective view showing an example of a conductor having a rectangular wire shape; FIG. 5 is a cross-sectional view cut along the axis of the conductor, schematically showing a state in which an adhesive is attached to the conductor shown in FIG. 4; FIG. 5 is a cross-sectional view cut along the axis of the conductor, schematically showing a state in which an adhesive and insulating particles are attached to the conductor of FIG. 4; FIG. FIG. 7 is a front view schematically showing a state in which the rectangular wire-shaped coil shown in FIG. 6 is inserted into slots of a stator core; FIG. 8 is a partial cross-sectional view of a slot portion into which the rectangular wire-shaped coil shown in FIG. 7 is inserted, taken perpendicularly to the axial direction of the stator; FIG. 8 is a front view schematically showing how the end portion side of the flat wire coil of FIG. 7 is bent; FIG. 5 is a cross-sectional view showing a rectangular wire coil used in another embodiment of the rotary electric machine of the present invention; FIG. 5 is a cross-sectional view showing a rectangular wire coil used in still another embodiment of the rotating electric machine of the present invention; FIG. 8 is a plan view showing a rectangular wire coil used in still another embodiment of the rotating electric machine of the present invention; FIG. 8 is a plan view showing a rectangular wire coil used in still another embodiment of the rotating electric machine of the present invention;

A stator for a rotating electrical machine and a rotating electrical machine according to the present invention will be described in detail below with reference to the drawings. Note that the dimensional ratios in the drawings quoted below are exaggerated for convenience of explanation, and may differ from the actual ratios.

(First embodiment)
As shown in FIG. 1 , the rotating electrical machine 60 of this embodiment includes a rotating electrical machine stator 40 and a rotating electrical machine rotor 50 . As shown in FIGS. 2 and 3, the rotating electric machine stator 40 of the present embodiment has slots 20A that are drilled in a direction parallel to the axis and extend radially in a cross section perpendicular to the axis. It has a stator core 20, a flat wire coil 10 penetrating through the slot 20A, and a resin material 30 filled in the slot 20A together with the flat wire coil 10. As shown in FIG.

Here, in the illustrated example, the rectangular wire coil 10 protruding from the slot 20A of the stator core 20 is cast in the resin material 30. As shown in FIG. Although not shown, in a stator for a rotating electric machine, flat wire coils projecting from a plurality of slots of a stator core are actually connected. Assembled.

Further, as shown in FIGS. 2 and 3, the rectangular wire coil 10 used in this embodiment has a conductor 15 having a rectangular wire shape and an insulating projection 16 provided on the peripheral surface 15A of the conductor 15. there is

As shown in FIGS. 2 and 3, in the flat wire coil 10 used in the present embodiment, the insulating protrusion 16 has a structure in which an insulating material 161 is fixed to the peripheral surface 15A of the conductor 15 with an adhesive 169. The insulating material 161 constitutes insulating particles 163 having a spherical shape.

In the present invention, the insulating protrusions 16 exhibit a protective function, an electrical insulation function, and a resin filling promotion function.

The protection function is that when the conductor 15 is inserted into the slot 20A, the insulating projection 16 contacts the inner wall of the slot 20A before the conductor 15, so that the conductor 15 contacts the inner wall of the slot 20A and the conductor 15 It means the function to suppress or prevent the occurrence of scratches on the surface.

Further, the electrical insulation function means the function of ensuring or improving the electrical insulation between the conductor 15 and the inner wall of the slot 20A by the insulating projection 16. The electrical insulation between the conductor 15 and the inner wall of the slot 20A may be ensured only by the insulating projection 16, but the electrical insulation may be ensured by the insulating projection 16 and the resin material 30 described above. In addition, since the resin material 30 can also improve the insulating properties, the insulating projections 16 can be formed more simply than the insulating coating that is previously formed on the rectangular wire-shaped conductor.

Furthermore, the function of promoting resin filling means that the insulating projection 16 forms a gap between the conductor 15 and the inner wall of the slot 20A, and facilitates filling of the resin material 30 into this gap. The resin material 30 described above forms a heat transfer path in this gap and contributes to electrical insulation between the conductor 15 and the inner wall of the slot 20A. In addition, the dimension between the conductor 15 and the inner wall of the slot 20A can be narrowed within a range in which the resin material 30 can be filled.

Next, the advantages of this embodiment will be explained. According to the rotating electrical machine stator 40 of the present embodiment, since the conductor 15 having a rectangular wire shape and the rectangular wire coil having the insulating protrusions 16 provided on the peripheral surface 15A of the conductor are provided, the protection function and the electrical insulation function described above are provided. Also, the function of promoting resin filling is exhibited, and the heat dissipation can be improved. In addition, since there is no need to use an insulating resin bobbin, which has a limit in thinning, the space factor of the conductor in the slot can be increased. Furthermore, since the resin material 30 can ensure or compensate for the electrical insulation function, there is no need to use an expensive rectangular wire coil with an insulating coating formed in advance, and the cost can be reduced.

Since the rotary electric machine 60 of the present embodiment includes the stator 40 for a rotary electric machine, it is possible to increase the space factor of the conductors in the slots. Therefore, even if the motor size is the same, the output performance of the motor is improved. are doing.

In addition, since the insulating protrusion 16 has a structure in which the insulating material 161 (insulating particles 163) is fixed to the peripheral surface 15A of the conductor 15 by the adhesive 169, the gap filled with the resin becomes uniform and stable to some extent, and the above-described The protective function, electrical insulation function, and resin filling promotion function thus obtained are exhibited more stably and effectively.

The insulating particles 163 preferably have a particle size of 5 μm or more, more preferably 10 μm or more. The insulating particles 163 preferably have a particle size of 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. From the viewpoint of being able to cope with even higher voltage motors, it is preferable to set the particle size to 10 μm or more and 100 μm or less. Moreover, from the viewpoint of facilitating the formation of a gap of a constant size around the conductor 15 so that the resin can be easily filled, it is preferable that the particle sizes are uniform.

Here, the particle size of the insulating particles and the fiber diameter of the insulating fibers to be described later are obtained by observing the insulating particles, insulating fibers, etc. in a cross section of the insulating protrusion cut along the height direction with a scanning electron microscope (SEM) or the like. It is defined as the maximum distance between any two points on the contour line of insulating particles or insulating fibers.

In addition, from the viewpoint that it is easy to form gaps of a certain size, the shape of the insulating particles 163 is spherical, polyhedral, or three-dimensional star-shaped rather than cubic, plate-shaped, scale-shaped, or needle-shaped. Preferably. A typical example of the three-dimensional star shape is a shape obtained by forming a plurality of protrusions on the surface of a spherical particle, that is, a so-called confetti shape. When the insulating particles 163 having such a spherical shape or the like are fixed to the peripheral surface 15A of the conductor 15, they tend to form a gap of a constant size around the conductor 15 regardless of the adhesion direction. In addition, the insulating particles 163 have a shape suitable for sieving, and the particle size can be easily adjusted, so that they are easy to handle. Furthermore, the insulating particles 163 having a spherical shape or a confetti shape are less likely to damage the inner wall of the slot 20A. Moreover, the insulating particles 163 having a polyhedral shape or a confetti shape with projections on the surface are preferable because the gaps between the particles can be easily increased. Furthermore, since the particle size can be made uniform in the upstream process of the production process, it is easy to form a gap of a fixed size around the conductor 15, which is easy to fill with resin. It is easy to improve the quality of the stator and rotating electric machine.

Furthermore, in the present invention, the ratio of the actual surface area of the flat wire coil 10 to the apparent surface area of the flat wire coil 10 is preferably 1.1 or more and 3.0 or less, and more preferably 1.1 or more and 2.0 or less. It is more preferable to have By setting this ratio to 1.1 or more and 3.0 or less, it is possible to form a gap that facilitates resin filling, and the protective function, electrical insulation function, and resin filling promotion function described above can be exhibited more effectively.

Here, the apparent surface area of the flat wire coil is defined as the area of the circumscribed surface of the flat wire coil that is measured only in consideration of the insulating protrusions 16 and without considering the holes and grooves existing between the insulating protrusions 16. do. Such an apparent surface area can be calculated, for example, by actual measurement using a scanning electron microscope (SEM) photograph.

Also, the actual surface area of the flat wire coil is defined as the actual surface area of the flat wire coil measured in consideration of not only the insulating protrusions 16 but also the holes and grooves existing between the insulating protrusions 16 . Such an actual surface area can be calculated by, for example, a mercury intrusion method or actual measurement using a scanning electron microscope (SEM) photograph.

Furthermore, the height h of the insulating protrusion 16 (see FIGS. 2 and 3) is preferably 5 μm or more, more preferably 10 μm or more. Also, the height h of the insulating protrusion 16 is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. From the viewpoint that the gaps that are easily filled with resin can be made thin, and the above-described protective function, electrical insulation function, and resin filling promotion function can be more effectively exhibited, the height h of the insulating protrusions 16 is set to 10 μm or more and 100 μm or less. It is preferable to

Here, the height h of the insulating protrusion 16 is defined as the distance from the part in contact with the conductor 15 to the farthest protrusion. A portion in contact with the conductor 15 is made of an adhesive 169 or an insulating material 161 .

Furthermore, the ratio of the projected area of the insulating protrusions 16 to the apparent surface area of the flat wire coil 10 is preferably 1% by area or more, more preferably 5% by area or more, and more preferably 10% by area or more. More preferred. Also, this ratio is preferably 90 area % or less, more preferably 80 area % or less, and even more preferably 70 area % or less. In particular, when the insulating projections 16 are formed of insulating particles or insulating fibers, by setting this ratio to 1 area % or more and 70 area % or less, the peripheral surface 15A of the conductor 15 is physically protected from damage and the like. A gap that is easily filled with resin can be formed, and the protective function, electrical insulation function, and resin filling promotion function described above can be exhibited more effectively.

Next, a method of manufacturing a stator for a rotating electrical machine in the rotating electrical machine of the present embodiment will be described as an example with reference to the drawings.

A conductor 15 having a rectangular wire shape as shown in FIG. 4 is formed into a U shape by a bending device using a mold. Next, an adhesive 169 is applied to the straight portion of the conductor 15 as shown in FIG. 5 by brush or spray. Next, insulating particles 163 are formed with adhesive 169 as shown in FIG. It is fixed to the peripheral surface 15A of the conductor 15, and the insulating projection 16 is formed on the peripheral surface 15A of the rectangular wire-shaped conductor 15. As shown in FIG. In this manner, the rectangular wire coil 10 used in the rotating electric machine stator of the present embodiment is obtained.

Next, as shown in FIG. 7, the rectangular wire coil 10 thus obtained is inserted into slots (not shown) of the stator core 20 . In the illustrated example, only a portion (four) of the rectangular wire coils 10 is shown. In the rectangular wire coil 10 inserted into the slot 20A, as shown in FIG. 8, gaps are formed between the conductors 15 and between the conductors 15 and the inner wall of the slot 20A by insulating projections 16 provided on the peripheral surface 15A. can do. Next, as shown in FIG. 9, the base of the rectangular wire-shaped coil 10 is restrained by a holding jig 201, the tip of the rectangular wire-shaped coil 10 is brought into contact with a bending jig 203, and the projecting portions of the plurality of flat wire-shaped coils 10 are shown by arrows. Bend as indicated by Z. Furthermore, although not shown, this bending causes the ends of the flat wire coils to come into contact with each other, and the flat wire coils 10 are connected by welding them together.

After that, using an injection molding machine (not shown) or the like, the resin material 30 is filled in the slots 20A and the rectangular wire coils 10 projecting from the slots 20A of the stator core 20 are cast with the resin material 30. 1 to 3 is obtained.

In the manufacturing method described above, when obtaining the flat wire coil, insulating particles are added to the adhesive raw material in advance and dispersed uniformly, and after coating the conductor with the insulating particles, the adhesive on the surface side is dissolved. Alternatively, the insulating particles may protrude from the adhesive. In this case, the insulating particles can be evenly arranged on the peripheral surface of the conductor, so that the above-described protecting function, electrical insulating function, and resin filling promoting function can be exhibited more effectively. Further, the rectangular wire-shaped coil obtained by such a manufacturing method is easier to widen the gap and has a better resin filling property than the rectangular wire-shaped coil obtained by the above-described manufacturing method.

(Second embodiment)
As shown in FIG. 10, the rectangular wire coil 11 used in the rotary electric machine of the present embodiment is similar to the rectangular wire coil shown in FIGS. has the same structure as

In the flat wire coil 11 used in the rotary electric machine of this embodiment, the insulating material 161 is the insulating particles 163 having a confetti shape. It is possible to form a gap that is easy to fill with resin, and the protective function, electrical insulation function, and resin filling promotion function described above can be exhibited more effectively.

(Third Embodiment)
As shown in FIG. 11 , in the rectangular wire coil 12 used in the rotating electrical machine of this embodiment, the insulating projections 16 have a structure in which insulating particles 163 are fixed to the peripheral surface 15A of the conductor 15 with an adhesive 169 . Also, the insulating protrusion 16 has a structure in which a part of the insulating particles 163 is embedded in a layer made of the adhesive 169 . Furthermore, in the rectangular wire coil 12, the ratio of the embedding depths d2 and d3 of the insulating particles 163 to the particle diameter d1 of the insulating particles 163 is 1/4 or more and 3/4 or less. In the figure, the solid line indicates the adhesive 169x when this ratio is 1/4 (=d2/d1), and the dotted line indicates the adhesive 169y when this ratio is 3/4 (=d3/d1). show.

The rectangular wire coil 12 used in the rotating electric machine of this embodiment has the insulating particles 163 embedded in the above-described predetermined amount. The gap becomes stable, and it is possible to form a gap that is less likely to cause resin filling defects and is easy to be filled with resin. As a result, the protective function, electrical insulation function, and resin filling promotion function described above are exhibited more effectively. In addition, since the gap is formed to facilitate resin filling, the filling pressure during resin filling can be stabilized at a low level, and the quality of resin filling can be improved.

(Fourth embodiment)
As shown in FIG. 12, in the rectangular wire coil 13 used in the rotating electric machine of the present embodiment, the insulating protrusions 16 are formed of insulating fibers 165 that are spirally wound around the peripheral surface 15A of the conductor 15. It has the same structure as the rectangular wire coil shown in FIGS. The insulating fiber 165 may be mechanically wound around the conductor 15 and fixed, or may be fixed with an adhesive (not shown).

In the rectangular wire coil 13 used in the rotating electric machine of the present embodiment, the insulating fiber 165 is mechanically wound around the conductor 15. Therefore, by adjusting the pitch of the spiral during winding, it is easy to form a gap of a certain size. In addition, by adjusting the pitch of the spiral during winding, the actual surface area and the projected area of the insulating protrusions can be easily adjusted, making it easy to form appropriate gaps between the insulating fibers 165 . As a result, in addition to the advantages of the first embodiment, the resin flow resistance of the resin material can be reduced, and not only the above-described protection function, electrical insulation function, and resin filling promotion function can be exhibited more effectively, Production efficiency is superior to that of the embodiment. In addition, since there are no insulating protrusions on the surface of the flat wire coil made of insulating particles that are difficult to align in height, interference such as catching when the flat wire coil is inserted into the slot can be suppressed, and insertion efficiency can be improved. Furthermore, since it is not necessary to manage the powder itself or the liquid to which the powder is added, which is required when insulating particles are used, production equipment and storage equipment can be simplified.

As the insulating fiber 165, in addition to ordinary fibers, fibers formed from woven fabric, non-woven fabric, and knitted fabric can be used. Furthermore, the insulating fiber 165 preferably has a fiber diameter of 5 μm or more, more preferably 10 μm or more. Also, the fiber diameter is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. The fiber diameter is preferably 10 μm or more and 100 μm or less from the viewpoint of being able to cope with even higher voltages of motors.

(Fifth embodiment)
As shown in FIG. 13, in the rectangular wire coil 14 used in the rotating electric machine of the present embodiment, the insulating protrusions 16 are formed of an insulating fiber aggregate 167 provided on the peripheral surface 15A of the conductor 15. , has the same structure as the rectangular wire coil shown in FIGS. Here, in the illustrated example, the insulating fiber assembly 167 is made of woven fabric. The insulating fiber assembly 167 may be mechanically wound around the conductor 15 and fixed, or may be fixed with an adhesive (not shown).

In the flat wire coil 14 used in the rotary electric machine of the present embodiment, the conductor 15 is covered with the insulating fiber assembly 167, and there is no insulating protrusion due to insulating particles that are difficult to align in height on the surface thereof. In addition to the advantages of , it is possible to suppress interference such as catching when inserting the flat wire coil into the slot, and improve the insertability. Furthermore, since it is not necessary to manage the powder itself or the liquid to which the powder is added, which is necessary when insulating particles are used, production equipment and storage equipment can be simplified.

As the insulating fiber assembly 167, an insulating fiber assembly made of woven fabric, non-woven fabric, or knitted fabric can be mentioned. Furthermore, the insulating fiber assembly 167 preferably has a thickness of 5 μm or more, more preferably 10 μm or more. Also, the thickness is preferably 200 μm or less, more preferably 150 μm or less, and even more preferably 100 μm or less. The thickness is preferably 10 μm or more and 100 μm or less from the viewpoint of being able to cope with even higher voltage motors.

In the following, the materials and the like of the members forming the rotating electric machine stator of each embodiment described above will be described in detail.

Examples of materials for the resin material 30 include thermosetting resins such as epoxy resins and unsaturated polyester resins. These resins are sufficient as long as they have ordinary insulating properties, but if it is desired to achieve excellent insulating properties between the coil and the stator core, resins with excellent insulating properties may be used.

Examples of materials for the insulating material 161 include ceramic, glass, resin, and cellulose (paper). Ceramics and glass are preferable to resins and papers from the viewpoint of placing importance on wear resistance and hardness in the slot. Ceramic is preferable to glass from the viewpoint of being less likely to break. From the viewpoint of facilitating the insertion of the flat wire coil into the slot, an insulating material having a small coefficient of friction is preferable. Examples of such an insulating material include an insulating material having self-lubricating properties and an insulating material having a small surface roughness.

As the adhesive 169, for example, it is preferable that the insulating material can be fixed to the conductor while withstanding the heat resistance temperature of about 180° C. to 250° C. of the motor. . When bending the conductor of the adhesive-applied portion after applying the adhesive, the adhesive preferably has flexibility from the viewpoint of conformability. These adhesives are not particularly required to be insulating, but if they have insulating properties, the insulating function of the insulating projections 16 can be compensated.

10, 11, 12, 13, 14 flat wire coil 15 conductor 15A peripheral surface 16 insulating protrusion 161 insulating material 163 insulating particles 165 insulating fiber 167 insulating fiber assembly 169 adhesive 20 stator core 20A slot 30 resin material 40 stator 50 for rotary electric machine Rotary electric machine rotor 60 Rotary electric machine 201 Holding jig 203 Bending jig h Height d1 Particle diameter d2, d3 Buried depth

Claims (11)

1. A stator core having a slot, a rectangular wire-shaped coil passing through the slot, and a resin material filled in the slot together with the rectangular wire-shaped coil,
   A stator for a rotating electric machine, wherein the rectangular wire coil has a conductor having a rectangular wire shape and insulating projections provided on a peripheral surface of the conductor.
2. The stator for a rotary electric machine according to claim 1, wherein the ratio of the actual surface area to the apparent surface area of the rectangular wire coil is 1.1 or more and 3.0 or less.
3. The stator for a rotary electric machine according to claim 1 or 2, characterized in that the height of the insulating projections is 5 µm or more and 200 µm or less.
4. The electric rotating machine according to any one of claims 1 to 3, wherein the insulating protrusion includes an insulating material and an adhesive material, and the insulating material is fixed to the conductor by the adhesive material. for stator.
5. The stator for a rotary electric machine according to claim 4, wherein the insulating material contains at least one selected from the group consisting of insulating particles, insulating fibers, and insulating fiber aggregates.
6. The insulating protrusion has a structure in which a part of the insulating particles is embedded in the adhesive,
   6. The stator for a rotary electric machine according to claim 5, wherein a ratio of the embedding depth of the insulating particles to the particle diameter of the insulating particles is 1/4 or more and 3/4 or less.
7. The stator for a rotary electric machine according to claim 5 or 6, characterized in that said insulating particles have a spherical shape, a polyhedral shape, or a three-dimensional star shape.
8. The electric rotating machine according to any one of claims 1 to 3, wherein the insulating projection is formed of an insulating fiber wound spirally around the peripheral surface of the conductor. for stator.
9. 9. The stator for a rotary electric machine according to claim 6 or 8, wherein the ratio of the projected area of the insulating projections to the apparent surface area of the rectangular wire coil is 1 area % or more and 90 area % or less.
10. The stator for a rotary electric machine according to any one of claims 1 to 3, characterized in that said insulating protrusions are formed of an insulating fiber assembly provided on the peripheral surface of said conductor.
11. A rotating electrical machine comprising the stator for rotating electrical machine according to any one of claims 1 to 10 and a rotor for rotating electrical machine.

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