WO2023188530A1

WO2023188530A1 - Stator for rotary electric machine

Info

Publication number: WO2023188530A1
Application number: PCT/JP2022/043101
Authority: WO
Inventors: 哲行寺内
Original assignee: 株式会社Ihi
Priority date: 2022-03-31
Filing date: 2022-11-22
Publication date: 2023-10-05

Abstract

This stator for a rotary electric machine comprises a stator core 20 and a stator coil 21. The stator core 20 comprises a yoke having a cylindrical shape and teeth 20b protruding radially inward from the yoke. The stator coil 21 is arranged in a slot 20c formed between the adjacent teeth 20b. The stator coil 21 comprises straight-angle conductors 210. The straight-angle conductors 210 are arranged in the slot 20c in a radial direction or a circumferential direction of the cylindrical shape described above. A coolant channel groove 212 is formed on a surface of the straight-angle conductor 210 by press molding.

Description

Stator of rotating electric machine

The present disclosure relates to a stator for a rotating electrical machine.

A rotating electric machine such as a motor is equipped with a stator and a rotor. A rotating electric machine can function both as an electric motor drive and as an electric power generator. Some rotating electric machines have a rotor rotating inside a cylindrical stator, while others have a stator arranged inside a rotating cylindrical rotor. In a rotating electric machine in which a rotor rotates inside a cylindrical stator, the stator has a cylindrical yoke and a plurality of teeth protruding from the yoke inward in the radial direction of the cylinder. . Stator coils are routed within the plurality of slots formed between adjacent teeth. Patent Document 1 listed below also discloses such a rotating electric machine.

International Publication No. 2011/132784

In the rotating electrical machine disclosed in Patent Document 1, the stator is cooled by contacting a part of the stator core and the coil end of the stator coil with the circulating coolant. In addition, in the rotating electric machine disclosed in Patent Document 1, the rotor is also cooled by circulating a cooling fluid therein. Cooling allows the rotating electrical machine to be used in higher temperature environments and also prevents the efficiency of the rotating electrical machine from decreasing. However, in the rotating electric machine disclosed in Patent Document 1, the cooling liquid does not circulate inside the stator, and the stator is not sufficiently cooled. There is a desire to further cool the stator, and it is desirable to circulate cooling liquid such as oil inside the stator.

An object of the present disclosure is to provide a stator for a rotating electrical machine that has a structure that can cool the stator more effectively.

A stator for a rotating electric machine according to the present disclosure includes a stator core including a cylindrical yoke and a plurality of teeth protruding from the yoke inward in a radial direction of the cylindrical shape, and adjacent teeth in the plurality of teeth. and a stator coil wired in a slot formed between the teeth, the stator coil being constituted by a rectangular conductor, and the rectangular conductor having the diameter inside each of the slots. The rectangular conductors are arranged in the direction or the circumferential direction of the cylindrical shape, and the rectangular conductors are provided with coolant flow grooves press-formed on the surface thereof.

An insulating layer with a uniform thickness may be formed on the surface of the rectangular conductor.

The coolant flow groove may be formed as a flat groove.

The coolant flow grooves may be formed as a plurality of grooves arranged on any circumferential surface of the rectangular conductor in the width direction of the circumferential surface.

each of the slots has an elongated trapezoidal cross section that narrows inwardly in the radial direction, and the rectangular conductors are arranged in the radial direction within the interior of each of the slots; It has a trapezoidal cross section whose width becomes narrower toward the radially inward side, and the coolant flow groove is located on the radially outer side of the radially oriented surface of the rectangular conductor. It may be formed on the radial orientation surface.

The coolant flow path formed on the radially oriented surface on the outside in the radial direction may have a uniform flow path cross-sectional area for each radially oriented surface.

According to the stator of the rotating electrical machine of the present disclosure, the stator can be cooled even more effectively.

FIG. 1 is a partial sectional view of a rotating electric machine having a stator according to a first embodiment. FIG. 2 is an enlarged sectional view of the stator. FIG. 3 is an enlarged sectional view of the stator according to the second embodiment. FIG. 4 is an enlarged sectional view of the stator according to the third embodiment.

Hereinafter, embodiments of the stator 2 of the rotating electric machine 1 will be described with reference to the drawings.

A rotating electrical machine 1 including a stator 2 according to the first embodiment will be described with reference to FIGS. 1 and 2. As shown in FIG. 1, the rotating electric machine 1 functions as an SPM (Surface Permanent Magnet) type generator. The rotating electric machine 1 includes a stator 2 and a rotor 3.

The rotor 3 is rotatably provided inside the stator 2. The rotor 3 includes a rotating shaft 30, a rotor yoke 31, a permanent magnet 32, and a sleeve 33. The rotating shaft 30 is held in a case via a bearing, and the entire rotor 3 is rotatable. A rotor yoke 31 is fixed to the rotating shaft 30. A plurality of permanent magnets 32 are fixed on the outer peripheral surface of the rotor yoke 31. The permanent magnets 32 are arranged in eight rows in the circumferential direction, and a plurality (for example, four) of permanent magnets are arranged in each row in the axial direction.

In order to prevent the permanent magnet 32 from coming off the rotor yoke 31 due to the centrifugal force caused by the rotation of the rotor 3, a sleeve 33 is fixed to the outside of the permanent magnet 32 by shrink fitting. The sleeve 33 is made of iron-based metal. A plurality of coolant flow grooves 34 are formed in the axial direction on the outer peripheral surface of each permanent magnet 32. The coolant channel groove 34 forms a coolant channel between the permanent magnet 32 and the sleeve 33.

On the other hand, the stator 2 is fixed to the case of the rotating electrical machine 1 and includes a stator core 20 and a stator coil 21. The stator core 20 is composed of electromagnetic steel plates laminated in the axial direction, and includes a cylindrical yoke 20a and a plurality of (for example, 24 2) teeth 20b. A slot 20c is formed between adjacent teeth 20b. A stator coil 21 is wired within the slot 20c. The stator coil 21 is constituted by a quadrangular wire 21a. A "flat wire" has a rectangular cross section and is sometimes called a flat wire or a rectangular wire. The rectangular wire 21a of this embodiment has a trapezoidal cross section that becomes narrower inward in the radial direction within the slot 20c. Note that the rectangular wire 21a does not need to have a trapezoidal cross section outside the slot 20c. For example, the rectangular wire 21a may have a rectangular cross section at the coil end of the stator coil 21.

The tips of the teeth 20b extend in the circumferential direction to form a flange. The slot 20c has a trapezoidal cross section that is elongated in the radial direction. The inner width of the slot 20c narrows toward this flange, that is, toward the radial inward direction. Inside each slot 20c, four rectangular wires 21a having a trapezoidal cross section are arranged in the radial direction. The rectangular wire 21a is oriented such that the width of its cross section in the circumferential direction becomes narrower toward the inside in the radial direction. The circumferential width of the four rectangular wires 21a in each slot 20c gradually becomes narrower inward in the radial direction. The radial height of the rectangular wire 21a within the slot 20c gradually increases inward in the radial direction. The cross-sectional area of each quadrangular electric conductor 210 of the rectangular wire 21a, more specifically, the rectangular wire 21a to be described later, has the above-mentioned width and height, and is therefore approximately the same, and Electrical resistance is almost the same.

The rectangular wires 21a are arranged in the radial direction within the slot 20c with their side surfaces in contact with the inner surface of the slot 20c and with their radially oriented surfaces in contact with the adjacent rectangular wires 21a. ing. Note that the radially oriented surface is a surface oriented in the radial direction of the rectangular wire 21a, and is a surface corresponding to the upper base or lower base of the trapezoidal cross section. The most radially inner rectangular wire 21a is received by the flange at the tip of the teeth 20b described above. Note that a gap is formed between the tips of the flanges, and this gap is closed with a ceramic seal member 20d (see FIG. 2) that extends in the axial direction. The sealing member 20d prevents a cooling liquid, which will be described later, circulated inside the stator 2 from leaking into the storage space of the rotor 3.

The stator core 20 is constructed of a plurality of circumferential members 20X that form part of the yoke 20a, and a diameter member 20Y that forms the remaining portion of the yoke 20a and teeth 20b. As described above, the stator core 20 is made of electromagnetic steel plates laminated in the axial direction, so the circumferential member 20X and the diameter member 20Y are also made of electromagnetic steel plates laminated in the axial direction. The circumferential member 20X and the diameter member 20Y are arranged alternately in the circumferential direction to construct the stator core 20. The yoke 20a is formed of circumferential members 20X and outer circumferential portions of a diameter member 20Y, which are alternately arranged. The circumferential member 20X is located on the radially outer side of the slot 20c, and functions as a cap that presses the rectangular wire 21a housed in the slot 20c from the outside.

The circumferential members 20X and the diameter members 20Y, which are arranged alternately in the circumferential direction, are fixed on the outside by a case 22. Further, on the outer circumferential surface of the stator core 20, cooling fluid passage grooves 23 through which a cooling fluid, which will be described later, is circulated are provided extending in the axial direction. Coolant channel groove 23 forms a coolant channel between stator core 20 and case 22 .

As shown in FIG. 2, the rectangular wire 21a includes a rectangular conductor 210 and an insulating layer 211 formed on the outer surface of the rectangular conductor 210. The rectangular conductor 210 is made of copper, and is formed to have a trapezoidal cross section by press-molding a rectangular wire with a rectangular cross section using a mold. Therefore, the rectangular conductor 210 is press-molded so that the cross-sectional shape, that is, the circumferential width and the radial height, of the rectangular conductor 210 differs depending on the position at which it is arranged. The rectangular conductor 210 also has a trapezoidal cross section like the rectangular wire 21a, and has four peripheral surfaces. During press molding, the radial orientation surface of the four circumferential surfaces of the rectangular conductor 210 is recessed to form the coolant flow channel groove 212 at the same time. That is, the coolant channel groove 212 is formed by recessing the rectangular conductor 210 in the radial direction on one radially oriented surface of the adjacent rectangular wires 21a within the slot 20c.

In this embodiment, the coolant flow groove 212 is formed on the radially outer radially oriented surface of the rectangular wire 21a. That is, the coolant flow path groove 212 forms a coolant flow path together with the radially inner radially oriented surface of the flat wire 21a adjacent to the radially outer side. Therefore, the coolant flow groove 212 is not formed in the radially outermost rectangular wire 21a. In this embodiment, the coolant flow channel groove 212 is formed as a single groove that is flat with respect to the radial orientation surface. "Shallow groove with respect to the radially-oriented face" means that the circumferential width of the coolant flow groove 212 is larger than the radial depth. The coolant flow groove 212 extends linearly in the axial direction, and has a uniform circumferential width and a uniform radial depth along the axial direction.

When forming the rectangular wire 21a with a trapezoidal cross section, if the curvature of the acute corner of the trapezoid is large, the filling rate of the rectangular conductor 210 of the stator coil 21 into the slot 20c will decrease. A decrease in the filling factor of the rectangular conductors 210 means a decrease in the space factor, which is the proportion of the rectangular conductors 210 in the cross section of the stator coil 21. A decrease in the filling rate of the rectangular conductors 210 into the slots 20c causes a decrease in the efficiency of the rotating electric machine 1.

However, in this embodiment, when the rectangular conductor 210 is depressed by press molding to form the coolant flow channel groove 212, the rectangular conductor 210 is pushed into an acute corner. As a result, a decrease in the filling rate of the rectangular conductors 210 into the slots 20c can be avoided. In other words, the rectangular wire 21a having a structure in which the coolant flow groove 212 is formed on the radially outer radially oriented surface of the rectangular wire 21a can realize an efficient rotating electric machine 1. In order to force the rectangular conductor 210 into an acute corner by press molding, it is preferable to form the coolant channel groove 212 as a single flat groove. By forming the coolant flow groove 212 as a single flat groove, the cross-sectional area of the coolant flow groove 212 can be increased, and the volume of the rectangular conductor 210 pushed into the acute corner by press molding can be increased. can.

A thin insulating layer 211 having a uniform thickness is formed on the surface of the rectangular conductor 210 after press molding. Therefore, the above-mentioned decrease in the space factor due to the formation of the insulating layer 211 is suppressed to a minimum. The term "thin film" used here refers to a film that is thick enough to ensure insulation and mechanical strength. If the insulating layer 211 is too thin, dielectric breakdown is likely to occur no matter how insulating the layer is. Further, if the mechanical strength is such that the insulating layer 211 is peeled off due to vibrations or the like caused by the use of the rotating electrical machine 1, insulation properties cannot be ensured.

The insulating layer 211 of this embodiment is an insulating resin layer. For example, insulating layer 211 may be an enamel layer. However, the insulating layer 211 has a uniform thickness, and the coolant channel grooves 212 are not filled with the insulating layer 211. Further, in order to improve the insulation between the flat wires 21a and between the flat wires 21a and the stator core 20, an insulating sheet member such as insulating paper may be interposed. That is, the flat wire 21a may be in contact with the adjacent flat wire 21a or the inner surface of the slot 20c via such an insulating sheet.

The coolant is introduced into the coolant flow path formed by the coolant flow groove 212 at one coil end of the stator coil 21, and is discharged from the coolant flow path at the other coil end. By providing a difference between the coolant pressure at one coil end and the coolant pressure at the other coil end, the coolant can be circulated inside the coolant flow path. Similarly, the coolant can be circulated through the coolant flow path formed by the coolant flow groove 23 described above. Although not described in detail, the coolant is also circulated through the inside of the rotating shaft of the rotor 3 in the coolant flow path formed by the coolant flow path groove 34 of the rotor 3.

Here, the coolant channel groove 212 has a uniform channel cross-sectional area for each rectangular wire 21a. In other words, each of the three stages of coolant flow paths in FIG. 2 has the same cross-sectional area. Therefore, the flow path resistance of the coolant flowing through each coolant flow path becomes the same, and the coolant can uniformly circulate within all the coolant flow paths to cool the stator 2. When a portion of low flow path resistance occurs locally, the amount of coolant flowing through the portion of low flow path resistance increases, and the amount of coolant flowing through other portions decreases. If the circulation amount distribution becomes uneven in this way, it becomes impossible to uniformly cool the stator 2. In particular, in this embodiment, the coolant channel groove 212 is formed as a single flat groove on the circumferential surface of the rectangular wire 21a. Therefore, the cross-sectional area of the flow path is large, the flow resistance of the coolant can be reduced, and the circulation amount of the coolant can be increased to improve the cooling efficiency.

Furthermore, the heat of the stator 2 is transferred to the cooling fluid through the rectangular wire 21a. Since the side surface of the flat wire 21a is in contact with the inner surface of the slot 20c, the flat wire 21a easily receives heat from the stator core 20. Further, since the rectangular conductor 210 of the rectangular wire 21a is made of copper having high thermal conductivity, the rectangular wire 21a can efficiently receive heat and efficiently transfer the heat to the cooling liquid.

Next, the stator of the second embodiment will be described with reference to FIG. 3. In the first embodiment described above, the coolant channel groove 212 is formed as a single groove that is flat with respect to the radial orientation surface. In contrast, in this embodiment, the coolant flow grooves 212 are formed as a plurality of grooves arranged on the radial orientation surface in parallel to the width direction of the radial orientation surface, that is, the circumferential direction mentioned above. . The other configurations of the stator of this embodiment are the same as those of the first embodiment described above, so the same or equivalent configurations are given the same reference numerals and their redundant explanations will be omitted.

In this embodiment, as shown in FIG. 3, the coolant flow grooves 212 are formed as a plurality (six) of grooves arranged on the radial orientation surface in the width direction of the radial orientation surface. Also in this embodiment, each coolant channel groove 212 is formed linearly in the axial direction, and has a uniform circumferential width and a uniform radial depth along the axial direction. Therefore, also in this embodiment, the coolant channel groove 212 has a uniform channel cross-sectional area for each rectangular wire 21a. In other words, the cross-sectional areas of the three stages of cooling channels in FIG. 3 (the total cross-sectional area of the six grooves in each stage) are the same.

According to this embodiment, although the flow path resistance of the coolant flow groove 212 increases compared to the first embodiment, the contact area of the coolant can be increased. As the flow path resistance increases, the amount of coolant circulated decreases. However, on the other hand, by increasing the contact area of the cooling liquid, the amount of heat exchange can be increased. That is, the cooling efficiency can be controlled by considering the flow rate of the cooling liquid and the heat exchange efficiency. Cooling efficiency also varies depending on the characteristics of the coolant. For example, if the viscosity of the coolant is high, it may be possible to improve the cooling efficiency by prioritizing the flow velocity and adopting the configuration of the first embodiment, which has a large flow path cross-sectional area even if the contact area is small. be. On the other hand, when the viscosity of the coolant is low, the decrease in flow velocity is small, or rather the flow velocity can be increased, so it is better to adopt the configuration of this embodiment, which has a large total contact area even though the cross-sectional area of each flow path is small. In some cases, cooling efficiency can be improved.

As in the present embodiment, the coolant flow grooves 212 may be formed as a plurality of grooves arranged on any circumferential surface of the rectangular conductor 210 in the width direction of the circumferential surface. In this embodiment, the coolant channel grooves 212 are formed as a plurality of grooves arranged on the radially oriented surface of the rectangular conductor 210 in the width direction of the radially oriented surface. However, the coolant channel grooves 212 may be formed as a plurality of grooves arranged on the circumferentially oriented surface of the rectangular conductor 210 in the width direction of the circumferentially oriented surface, that is, in the radial direction described above.

Next, the stator of the third embodiment will be described with reference to FIG. 4. In the first and second embodiments described above, the rectangular wires 21a are arranged only in the radial direction within the slots 20c. In this embodiment, the rectangular wires 21a are arranged not only in the radial direction of the cylindrical yoke 20a but also in the circumferential direction. Note that the rectangular wires 21a may be arranged only in the circumferential direction. Further, the coolant flow groove 212 is formed by recessing the surface of the rectangular conductor 210 of the rectangular wire 21a, but in the first and second embodiments described above, the radially outer diameter Coolant flow grooves 212 were formed by recessing the orientation surface. However, the surface of the rectangular conductor 210 that is recessed to form the coolant flow groove 212 is not limited to a radially oriented surface, but may be a circumferentially oriented surface as in this embodiment.

Also in this embodiment, the cross-sectional area of each rectangular conductor 210 is approximately the same, and the electrical resistance per length is approximately the same. Coolant flow grooves 212 are formed only on one circumferential orientation surface of the circumferentially adjacent rectangular wires 21a, more specifically, only on the circumferential orientation surface facing the other of the adjacent rectangular wires 21a. As a result, one coolant flow groove 212 is formed in each row arranged in the radial direction. Also in this embodiment, the cross-sectional area of each of the coolant flow grooves 212 is uniform, and the flow resistance of the coolant flowing through each row of coolant flow channels arranged in the radial direction is the same. Therefore, the coolant can circulate uniformly in all the coolant flow paths to cool the stator.

Note that in this embodiment, the coolant flow groove 212 is formed on one of the opposing circumferential orientation surfaces of the adjacent rectangular wires 21a. By doing so, the stator coil 21 can be cooled more effectively from the inside. However, the coolant flow groove 212 may be formed on the circumferential orientation surface of the rectangular wire 21a facing the teeth 20b. In this way, stator core 20 as well as stator coil 21 can be effectively cooled. Further, even when the coolant flow grooves 212 are formed on the radially oriented surface, the coolant flow grooves 212 may be formed on the radially inner surface instead of the radially outer side. Within one slot 20c, the coolant flow grooves 212 may be provided on each of the radial orientation surface and the circumferential orientation surface.

According to the above embodiment, the stator coil 21 is composed of the rectangular conductor 210. The rectangular conductors 210 are arranged radially or circumferentially within the slot 20c. Coolant flow grooves 212 are press-molded on the surface of the rectangular conductor 210, that is, on the radial orientation surface or the circumferential orientation surface. Therefore, the stator can be cooled from the inside more effectively by the coolant circulating in the coolant flow path formed by the coolant flow path groove 212.

Further, in the embodiment described above, coolant flow paths are formed by the coolant

flow path grooves

212, 23, and 34 at various locations, but the coolant flow path by the coolant flow path grooves 212 is formed in the rectangular conductor of the stator coil 21. 210. The rectangular conductors 210 extend in the axial direction over the entire length of the stator 2, and are housed in slots 20c arranged at regular intervals in the circumferential direction. Therefore, according to the coolant flow path formed by the coolant flow path groove 212, the entire stator 2 can be efficiently cooled. Furthermore, in the stator 2, the stator coil 21 is a part that easily becomes high temperature, and since the cooling liquid removes heat from the rectangular conductor 210 of the stator coil 21, the stator coil 21 can be efficiently cooled.

Furthermore, according to the above embodiment, the rectangular conductor 210 has the insulating layer 211 with a uniform thickness on its surface. In other words, the rectangular conductor 210 and the insulating layer 211 constitute the rectangular wire 21a, and the rectangular wire 21a constitutes the stator coil 21. The insulating layer 211 has a uniform thickness, does not fill the coolant flow channel groove 212 formed in the rectangular conductor 210, and does not impede cooling by the coolant flow channel. Further, the insulating layer 211 having a uniform thickness does not reduce the above-mentioned space factor, nor does it reduce the filling rate of the rectangular conductors 210 into the slots 20c. Therefore, the efficiency of the rotating electric machine 1 does not decrease.

Further, since the insulating layer 211 is formed to have a uniform thickness, it is possible to prevent a decrease in rigidity and strength of the surface of the rectangular wire 21a. The rectangular wire 21a is densely stored in the slot 20c, but if the surface of the rectangular wire 21a has low rigidity or strength, the rectangular wire 21a, more specifically, the rectangular conductor 210, cannot be firmly held within the slot 20c. There is a risk. However, such a problem does not occur in the above embodiment.

According to the first and third embodiments described above, the coolant flow channel groove 212 is formed as a flat groove. The flat shape of the coolant channel groove 212 is a shape suitable for reducing channel resistance and increasing the contact area. Further, the flat shape also makes it easy to form the coolant flow grooves 212 on the circumferential surface of the rectangular conductor 210. Even if the grooves have the same aspect ratio, it is difficult to form the coolant channel grooves 212 as narrow and deep grooves.

According to the second embodiment, the coolant flow grooves 212 are formed as a plurality of grooves arranged on any circumferential surface in the width direction of the circumferential surface. By forming the coolant channel grooves 212 in this way, the contact area with the coolant can be increased and the heat exchange efficiency can be improved, that is, the cooling efficiency can be improved.

Furthermore, according to the above embodiment, the slot 20c has a long trapezoidal cross section whose width becomes narrower toward the radial inward side. Here, the rectangular conductors 210 are arranged in the radial direction within the slot 20c and have a trapezoidal cross section whose width becomes narrower toward the inside in the radial direction. Furthermore, the coolant flow groove 212 is formed on the radially outer radially oriented surface of the radially oriented surface of the rectangular wire 21a. That is, the coolant flow groove 212 is formed on a radially oriented surface having a wide circumferential width. With such a structure, it is possible to improve the filling rate of the rectangular conductor 210 having a trapezoidal cross section into an acute corner. As a result, the filling rate of the rectangular conductors 210 into the slots 20c can be improved, and an efficient rotating electric machine 1 can be realized.

Further, according to the first and second embodiments, the coolant flow groove 212 has a uniform flow cross-sectional area for each radial orientation surface on which the coolant flow groove 212 is formed. There is. Therefore, for example, in the three-stage coolant flow path shown in FIG. The stator 2 can be uniformly cooled by uniformly circulating the inside of the stator 2.

Note that in the above embodiment, the coolant flow groove 212 is formed linearly in the axial direction. Although the flow resistance of the flow path formed by the coolant flow groove 212 increases, the coolant flow groove 212 may meander in order to increase the contact area of the coolant. In the embodiment described above, the coolant flow groove 212 is formed only on one of the four circumferential surfaces of the rectangular conductor 210. However, the coolant flow grooves 212 may be provided on two or more circumferential surfaces of all the circumferential surfaces of the rectangular conductor 210. In the above embodiment, the coolant flow grooves 212 are formed as a plurality of grooves arranged in parallel on the radially oriented surface, but the coolant flow grooves 212 as a plurality of grooves arranged in parallel are circumferentially oriented. It may also be formed on a surface.

Further, although the rotating electric machine 1 in the above embodiment is an SPM type generator, it may be an IPM (Interior Permanent Magnet) type generator. The rotating electric machine may be an electric motor instead of a generator. Furthermore, the rotating electric machine may be an induction type rotating electric machine that does not have a permanent magnet.

This application claims priority based on Japanese Patent Application No. 2022-58767 filed on March 31, 2022, and the entire contents of this application are incorporated herein by reference.

1 Rotating electric machine 2 Stator 20 Stator core 20a Yoke 20b Teeth 20c Slot 21 Stator coil 210 Rectangular conductor 211 Insulating layer 212 Coolant flow groove 3 Rotor

Claims

a stator core having a cylindrical yoke and a plurality of teeth protruding from the yoke radially inward of the cylindrical shape;
A stator for a rotating electric machine including a stator coil wired in a slot formed between adjacent teeth of the plurality of teeth,
The stator coil is composed of a rectangular conductor,
The rectangular conductors are arranged inside each of the slots in the radial direction or the circumferential direction of the cylindrical shape,
A stator for a rotating electric machine, wherein the rectangular conductor has coolant flow grooves press-molded on its surface.
The stator for a rotating electrical machine according to claim 1, wherein an insulating layer with a uniform thickness is formed on the surface of the rectangular conductor.
The stator of a rotating electrical machine according to claim 1 or 2, wherein the coolant flow groove is formed as a flat groove.
According to any one of claims 1 to 3, wherein the coolant flow groove is formed as a plurality of grooves arranged on the circumferential surface of the rectangular conductor in the width direction of the circumferential surface. The stator of the mentioned rotating electric machine.
Each of the slots has an elongated trapezoidal cross section that narrows in width in the radial direction;
The rectangular conductors are arranged in the radial direction inside each of the slots and have a trapezoidal cross section that becomes narrower toward the radial inward,
Any one of claims 1 to 4, wherein the coolant flow groove is formed on the radially oriented surface on the radially outer side of the radially oriented surface of the rectangular conductor. The stator of the rotating electric machine described in .
The stator of a rotating electrical machine according to claim 5, wherein the coolant flow groove formed on the radially oriented surface on the outside in the radial direction has a uniform flow path cross-sectional area for each radially oriented surface. .