JP2017127184A - motor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress a difference in magnetic saturation between an inner diameter side and an outer diameter side of an annular stator, in a motor that comprises rotors at the inner diameter side and the outer diameter side.SOLUTION: A motor comprises: an annular stator 10 that comprises inner teeth protruded toward an inner diameter side and outer teeth protruded toward an outer diameter side; an inner rotor opposed to the inner diameter side of the annular stator 10; and an outer rotor opposed to the outer diameter side of the annular stator 10. At an inner slot 17 between the inner teeth and an outer slot 16 between the outer teeth, a first coil 50 with toroidal winding is arranged. At the outer slot 16, the first coil 50, and a second coil 60 with distribution winding to which a current having the same timing and in the same direction as the first coil 50 is energized are arranged.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor, and more particularly to a motor provided with a rotor inside and outside a stator.

  Conventionally, a toroidal motor having a rotor on the inside and outside of a stator has been proposed.

  FIG. 6 shows a configuration of a conventional motor described in Patent Document 1. The motor includes a stator 100, an inner rotor 20, and an outer rotor 30.

  The stator 100 includes a stator yoke 14, and outer teeth 12 and inner teeth 13 provided on the stator yoke 14, and the stator yoke 14 is provided with a three-phase coil 15. The coil 15 is star or delta connected.

  The inner rotor 20 is rotatably held inside the stator 100 and includes a rotor yoke 21 and a permanent magnet 22. In addition, the outer rotor 30 is rotatably held outside the stator 100 and includes a rotor yoke 31 and a permanent magnet 32. The inner rotor 20 and the outer rotor 30 are rotated by a magnetic field generated by a current flowing through the coil 15. FIG. 4 shows a surface magnet type rotor in which the permanent magnet 22 and the permanent magnet 32 are provided on the surfaces of the rotor yoke 21 and the rotor yoke 31, respectively.

  Between the outer teeth 12 projecting from the stator yoke 14 in the outer circumferential direction and the inner teeth 13 projecting from the stator yoke 14 in the inner circumferential direction in the same number as the outer teeth 12, an outer slot 16 and an inner A slot 17 is provided, and the areas of the outer slot 16 and the inner slot 17 are set equal.

Patent No. 4983022

  In the above prior art, by setting the areas of the outer slot 16 and the inner slot 17 equal, the coils are wound in an aligned manner, and the space factor can be improved and the copper loss can be reduced.

  However, the inner rotor 20 and the outer rotor 30 have different perimeters per pole pair, and the outer rotor 30 side is long and the inner rotor 20 side is short. For this reason, if the same magnetomotive force is set on the inner side and the outer side, the magnetomotive force per unit circumference is smaller on the outer side than on the inner side, so the saturation situation of the core differs between the inner side and the outer side. This is an obstacle to further miniaturization of the motor.

  FIG. 7 schematically shows the coils 50 provided in the outer slot 16 and the inner slot 17 in the motor shown in FIG. The coil 50 is a toroidal winding connected to a yoke of a substantially annular stator 100 in a three-phase star or delta shape. The number of coils and the coil diameter are the same on the inside and outside, and the current is also the same. Since the outer circumference is longer than the inner circumference, the amount of current per unit circumference is smaller on the outer side than on the inner side.

  Although it is conceivable to set the number of coils small so as not to cause magnetic saturation on the inner side, in this case, the magnetic flux is insufficient on the outer side.

  An object of the present invention is to suppress a difference in magnetic saturation between an inner diameter side and an outer diameter side in a motor including rotors on an inner diameter side and an outer diameter side of an annular stator.

  The motor according to the present invention includes an annular stator having an inner tooth projecting toward the inner diameter side and an outer tooth projecting toward the outer diameter side, an inner rotor facing the inner diameter side of the annular stator, and an outer surface facing the outer diameter side of the annular stator. A rotor, a toroidal-wound multi-phase first coil disposed in an inner slot between the inner teeth and an outer slot between the outer teeth, and an outer slot, each of the plurality of phases being disposed in the same outer slot A second coil having a plurality of phases through which currents in the same timing and direction as the first coil are supplied.

  The motor according to the present invention includes an annular stator having an inner tooth projecting toward the inner diameter side and an outer tooth projecting toward the outer diameter side, an inner rotor facing the inner diameter side of the annular stator, and an outer diameter side facing the annular stator. The outer rotor, the inner slot between the inner teeth and the outer coil between the outer teeth, the three-phase first coil of toroidal winding, and the outer slot, and the three phases are arranged in the same outer slot. And a three-phase second coil through which current in the same direction and direction is supplied as the first coil.

  In a preferred configuration of the present invention, the first coil is disposed on the inner diameter side of the outer slot, and the second coil is disposed on the outer diameter side of the outer slot.

  In another preferred configuration of the invention, the second coil is a distributed or concentrated winding coil.

  In still another preferred configuration of the present invention, the cross-sectional shapes of the inner teeth and the outer teeth are rectangular and have the same width.

  In still another preferred configuration of the present invention, the outer slot has a first slot portion on the inner diameter side and a second slot portion on the outer diameter side, and the first slot portion and the inner slot have the same length in the circumferential direction. The length of the second slot portion in the circumferential direction is larger than the length of the first slot portion in the circumferential direction, the first coil is disposed in the inner slot and the first slot portion, and the second slot portion is in the second slot portion. Two coils are arranged, and the second coil is a distributed winding coil.

  In still another preferred configuration of the present invention, the first slot portion and the inner slot have the same length on both side surfaces in the radial direction passing through the center in the circumferential direction when viewed from one axial side. .

  In still another preferred configuration of the present invention, the first coil is formed by a rectangular wire having a rectangular cross-sectional shape.

  According to the present invention, in a motor provided with a rotor on the inner diameter side and the outer diameter side of the annular stator, the difference in magnetic saturation between the inner diameter side and the outer diameter side can be suppressed. The difference in the amount of coil current per circumference can be suppressed. According to the present invention, the torque per core volume, that is, (torque) / (core volume) can be increased.

It is a coil block diagram of the motor of embodiment. It is magnetic flux explanatory drawing in the stator of the motor of embodiment. It is a graph of the amount of current per circumference on the outer rotor side (outer rotor side) / current amount per circumference on the inner rotor side (inner rotor side) of the motor of the embodiment. It is a coil block diagram in the stator of the motor of another example of embodiment. FIG. 5 is an enlarged view corresponding to a portion A in FIG. 4 showing an arrangement example of first coils arranged in an inner slot and an outer slot of the stator in the configuration of FIG. 4. It is a block diagram of the conventional motor. It is a coil block diagram of the conventional motor.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

<Basic principle>
First, the basic principle of this embodiment will be described.

  The precondition of the motor of the present embodiment is an annular stator having an inner tooth projecting to the inner diameter side and an outer tooth projecting to the outer diameter side, an inner rotor on the inner diameter side of the annular stator, and an outer side on the outer diameter side. A motor including a rotor.

  In the motor having such a configuration, the toroidal coil is disposed in the inner slot between the inner teeth and the outer slot between the outer teeth. Of course, the inner circumference side is longer than the outer circumference side circumference. Also short. For this reason, when the coil is energized, the current amount per circumference on the inner diameter side becomes larger than the current amount per circumference on the outer diameter side, and the magnetic flux density on the inner diameter side becomes larger than that on the outer diameter side. Considering this point, if the number of toroidal winding coils is reduced in order to suppress magnetic saturation on the inner diameter side, in this case, although magnetic saturation is suppressed on the inner diameter side, there is insufficient magnetic flux on the outer diameter side, and torque It leads to shortage.

  Therefore, in the present embodiment, focusing on the outer slot among the inner slot and the outer slot in which the toroidal coil is disposed, an auxiliary coil is added to the outer slot to compensate for the shortage of the magnetic flux on the outer diameter side. It is a thing. When the toroidal coil is the first coil and the added coil is the second coil, the first coil is arranged in the inner slot, but the first coil and the second coil are arranged in the outer slot. Become. For example, when each of the first coil and the second coil is a three-phase coil, each of the three-phase second coils is energized at the same timing as the first coil arranged in the same outer slot in the same phase, And it supplies with electricity in the same direction as the 1st coil. Thereby, more magnetic flux than the inner diameter side is generated only in the magnetic circuit on the outer diameter side, and sufficient magnetic flux is generated on the outer diameter side while suppressing magnetic saturation on the inner diameter side, thereby preventing torque shortage. The first coil is a toroidal winding, but the second coil may be a distributed winding arranged in a plurality of outer slots, for example. Further, the first coil and the second coil may be a first coil of a plurality of phases other than three phases and a second coil of a plurality of phases, respectively. In this case, each of the second coils of the plurality of phases may be energized at the same timing as the first coil arranged in the same outer slot in the same phase and energized in the same direction as the first coil. Good.

  Here, in a bearingless motor that generates torque and radial electromagnetic force with a single electromagnetic machine, it is possible to use a toroidal coil and a distributed coil together for the purpose of torque and radial electromagnetic force (magnetic levitation), respectively. Are known. In the present embodiment, in a motor including an inner rotor and an outer rotor, a plurality of magnetic flux densities on the inner diameter side and the outer diameter side are made uniform by suppressing the difference in magnetic saturation between the inner diameter side and the outer diameter side. Please note that the coil is used together. Note that the magnetic flux density on the inner diameter side and the outer diameter side may be a configuration that is not strictly uniform as long as it is a configuration that can be made uniform compared to a configuration without the second coil.

<Configuration>
Next, a specific configuration of the present embodiment will be described.

  FIG. 1 shows a coil structure of a motor in this embodiment. The overall configuration of the motor of the present embodiment is substantially the same as that of the conventional motor shown in FIG. That is, the motor includes the annular stator 10, the inner rotor 20, and the outer rotor 30.

  The annular stator 10 includes a stator yoke 14, an outer tooth 12 and an inner tooth 13 provided on the stator yoke 14, and the stator yoke 14 is provided with a three-phase coil. The three-phase coil is a toroidal coil 50 shown below, and is star-connected or delta-connected.

  The inner rotor 20 is rotatably held inside the stator 10 and includes a rotor yoke 21 and a permanent magnet 22. The outer rotor 30 is rotatably held outside the stator 10 and includes a rotor yoke 31 and a permanent magnet 32. The inner rotor 20 and the outer rotor 30 are rotated by a magnetic field generated by a current flowing through the coil 50. Permanent magnets 22 and 32 are provided on the surfaces of the rotor yokes 21 and 31, respectively.

  Between the outer teeth 12 projecting from the stator yoke 14 in the outer circumferential direction and the inner teeth 13 projecting from the stator yoke 14 in the inner circumferential direction in the same number as the outer teeth 12, an outer slot 16 and an inner A slot 17 is provided.

  In the conventional motor, only the toroidal coil (first coil) 50 is disposed in the outer slot 16 and the inner slot 17. On the other hand, in the present embodiment, the inner slot 17 is provided with a toroidal coil 50 as in the conventional case, but the outer slot 16 is provided with a further distributed coil on the outer diameter side in addition to the toroidal coil 50. (Second coil) 60 is arranged.

  That is, the outer slot 16 includes two types of coils, a toroidal coil 50 and a distributed coil 60. It can be said that the toroidal coil 50 is disposed on the inner diameter side of the outer slot 16 and the distributed coil 60 is disposed on the outer diameter side.

  The distributed-winding coil 60 is not arranged in a concentrated manner in one slot but is distributed in a plurality of slots, and each is connected by distributed winding via a coil end. The The distributed winding coil 60 is connected at a coil end extending in the radial direction at the same timing as the toroidal winding coil 50 and in the same direction as the current flowing in the toroidal winding coil 50.

  For example, in FIG. 1, the coil 50 and the coil 60 are schematically shown by different types of hatching. Referring to FIG. 1, the direction of the current between the coil 50 and the coil 60 will be described in detail. The current of the coil 50 in the outer slot 16 is the direction from the near side of the page to the far side of the page. It is assumed that the current is in the direction from the back side of the page to the front side of the page. At this time, the current of the coil 60 of the outer slot 16 is also energized in the direction from the near side of the paper surface to the far side of the paper surface.

  FIG. 2 schematically shows the flow of magnetic flux of the coil structure in this embodiment in comparison with the conventional coil structure. FIG. 2A shows the flow of magnetic flux in the coil structure in the conventional stator 100 shown in FIG. 7, and FIG. 2B shows the flow of magnetic flux in the coil structure in the stator 10 of the present embodiment.

  In the conventional coil structure, only the toroidal coil 50 is disposed in the outer slot 16 and the inner slot 17, and when the coil 50 is energized, only the magnetic flux indicated by the solid line in FIG. On the other hand, in the coil structure of the present embodiment, a distributed winding coil 60 is disposed in the outer slot 16 in addition to the toroidal winding coil 50. Thereby, when the coil 50 and the coil 60 are energized, a magnetic flux as shown by the solid line and the broken line in FIG. 2B is generated, and a large amount of magnetic flux can be generated only in the magnetic circuit on the outer peripheral side. In FIG. 2B, the magnetic flux indicated by a broken line indicates a magnetic flux newly generated by energization of the coil 60.

  As described above, in this embodiment, it is possible to generate a large amount of magnetic flux only in the magnetic circuit on the outer peripheral side by the coil 60. Therefore, it is possible to suppress magnetic saturation in the inner peripheral teeth having a short peripheral length, improve the magnetic flux density in the outer peripheral teeth having a long peripheral length, and increase the torque.

  As described above, in the conventional coil structure, if the number of the toroidal coils 50 is set to be small so that the magnetic saturation is not performed on the inside, the magnetic flux is insufficient on the outside. In this regard, in the present embodiment, the shortage of magnetic flux on the outside is compensated by the distributed winding coil 60 arranged on the outer diameter side of the outer slot 16.

<Amount of current per circumference>
FIG. 3 is a graph showing (current amount per circumferential length on the outer rotor side) / (current amount per circumferential length on the inner rotor side) of the coil structure in the present embodiment in comparison with the conventional coil structure. In the figure, the horizontal axis is (stator outermost diameter radius / stator outermost diameter radius), and indicates that the value increases as the value increases. The vertical axis represents (current amount per circumference on the outer rotor side) / (current amount per circumference on the inner rotor side), the solid line 150 indicates the coil structure of the present embodiment, and the solid line 200 indicates the conventional coil structure. .

  In the conventional coil structure, as shown by the solid line 200, the circumference on the outer circumference is longer than the circumference on the inner circumference. Therefore, if the same amount of current flows through the inner circumference and the outer circumference, the current quantity per unit circumference becomes the outer circumference. As it goes, it decreases monotonously. On the other hand, in the present embodiment, the current amount on the outer peripheral side is increased by the coil 60, so that the current amount per unit peripheral length can be maintained substantially the same on the inner periphery and the outer periphery as indicated by the solid line 150. .

  The inventors of the present application analyzed the magnetic flux density by computer simulation when the coil 50 in the outer slot 16 and the coil 50 in the inner slot 17 had the same cross-sectional area and the same amount of current was applied. As a result, it is confirmed that the magnetic flux density on the outer periphery is significantly lower than the magnetic flux density on the inner periphery, and when the coil 60 is additionally arranged on the outer diameter side of the outer slot 16 as in this embodiment, the magnetic flux on the outer periphery It has been confirmed that the density has increased to almost the same level as the magnetic flux density on the inner periphery.

  As described above, according to the present embodiment, since the distributed winding coil 60 is arranged in the outer slot 16 in addition to the toroidal winding 50, the current distribution between the inner periphery and the outer periphery is changed to change the outer periphery side. More current can be applied. As a result, it is possible to prevent a shortage of magnetic flux on the outer peripheral side while suppressing magnetic flux saturation on the inner peripheral side.

  In general, in a distributed winding coil, since a plurality of coils intersect, the coil end becomes larger in the axial direction. In this embodiment, the toroidal winding coil 50 and the distributed winding coil 60 are combined, and the distributed winding coil 60 is used as an auxiliary coil of the toroidal winding coil 50 only on the outer diameter side of the outer slot 16. Is arranged. Thereby, the quantity of the coil 60 of distributed winding can be reduced, and the increase in a coil end can be suppressed to the minimum. That is, according to the present embodiment, the coil end can be reduced in size, the electromagnetic force distribution between the inner and outer rotors can be optimized, and (torque) / (core volume) can be increased as compared with the conventional motor.

  Further, in this embodiment, the magnetic flux on the outer peripheral side is increased by the coil 60, but by adjusting the amount of the coil 60 so that the current flows in accordance with the ratio of the peripheral lengths of the inner and outer peripheral gap portions. The inner and outer magnetic flux densities may be exactly the same. Further, the rotor may be an embedded magnet type (IPM) instead of a surface magnet type (SPM).

  Furthermore, in this embodiment, you may set so that the cross-sectional shape of the outer teeth 12 and the inner teeth 13 may be a rectangle, and may have the same width. Thereby, the magnetic saturation of the outer teeth and the inner teeth can be made constant.

  Next, a configuration of another example of the embodiment will be described. FIG. 4 is a coil configuration diagram of the stator 10 of the motor of another example of the embodiment. FIG. 5 is an enlarged view corresponding to the portion A of FIG. 4 showing an example of the arrangement of the first coils arranged in the inner slot 17 and the outer slot 16 of the stator 10 in the configuration of FIG.

  In the configuration shown in FIGS. 4 and 5, the shape of the inner slot 17 and the outer slot 16 in the stator 10 is changed with respect to the configuration shown in FIGS. 1 and 2B. Specifically, in the outer slot 16, the cross-sectional shape of the plane orthogonal to the axial direction of the stator 10 is a T-shape having a wide outer diameter side. On the other hand, the inner slot 17 has a rectangular cross-sectional shape with respect to a plane orthogonal to the axial direction of the stator 10. More specifically, the outer slot 16 includes a first slot portion 18 (FIG. 5) having a rectangular cross section formed on the inner diameter side, and a cross section formed continuously on the outer diameter side from the first slot portion 18. It has a rectangular second slot portion 19 (FIG. 5). The length L19 in the circumferential direction of the second slot portion 19 is larger than the length L18 in the circumferential direction of the first slot portion 18. The “circumferential direction” means the circumferential direction of the stator 10. The central position O1 in the circumferential direction of the first slot portion 18 and the central position O2 in the circumferential direction of the second slot portion 19 coincide with each other in the circumferential direction of the stator 10.

  Further, each of the plurality of inner slots 17 is arranged away from the inner diameter side of the corresponding outer slot 16 so that the corresponding outer slot 16 and the center position in the circumferential direction coincide with each other in the circumferential direction. The first slot portion 18 and the inner slot 17 of the outer slot 16 have substantially the same rectangular shape. Specifically, the first slot portion 18 and the inner slot 17 have the same lengths L18 and L17 in the circumferential direction. Further, the first slot portion 18 and the inner slot 17 have a length D18 on both sides in the radial direction in the radial direction passing through the circumferential centers O1 and O2 when viewed from one axial side of the stator 10 as shown in FIG. , D17 are the same. The “radial direction” means the radial direction of the stator 10. Both side surfaces in the circumferential direction of the first slot portion 18 and the inner slot 17 are planes parallel to the radial direction, respectively, when viewed from one axial side of the stator 10.

  A toroidal coil (first coil) 50 a is disposed in the inner slot 17 and the first slot portion 18. As shown in FIG. 5, the coil 50a is formed by a rectangular wire having a rectangular shape such as a rectangle in cross section. In FIG. 4, in the coil 50a, the connection between the portion disposed in the inner slot 17 and the portion disposed in the first slot portion 18 of the outer slot 16 is schematically illustrated by the elongated white rectangular connection portion. It shows. Actually, as shown in FIG. 5, the toroidal coil 50a is arranged in the inner slot 17 and the first slot portion 18 so as to be arranged adjacent to each other in the circumferential direction and the radial direction.

  A distributed winding coil (second coil) 60 a (FIG. 4) is disposed in the second slot portion 19 adjacent to the outer diameter side of the first slot portion 18. In FIG. 5, the distributed winding coil is not shown.

  According to the above configuration, the inner slot 17 and the first slot portion 18 of the outer slot 16 have the same circumferential length and the same radial length on both sides in the circumferential direction. 16, the space factor of the coil 50a can be improved. In particular, since a rectangular wire is used for the toroidal coil 50a, the space factor of the coil 50a in the inner slot 17 and the outer slot 16 can be further improved. This makes it easy to reduce the size of the motor. Further, in the distributed winding coil 60a, the circumferential length of the portion disposed on the outer diameter side of the outer slot 16 can be increased, so that an increase in the radial length of this portion can be suppressed and the outer rotor side can be prevented. Insufficient magnetomotive force can be suppressed or prevented.

  On the other hand, even in the case of the configuration shown in FIGS. 1 and 2B, a rectangular wire can be used for the toroidal coil 50. However, in this case, there is room for improvement in terms of improving the space factor. For example, when a rectangular wire is used for the toroidal coil 50 in the configuration of FIG. 1 and FIG. 2B, the shape of the portion occupied by the coil 50 in each of the inner slot 17 and the outer slot 16 is the circumferential length. Are the same rectangle. At this time, the toroidal coil 50 can be easily wound at a short distance. On the other hand, in the configuration of FIG. 1 and FIG. 2B, the circumferential length of the outer slot 16 is larger than that of the inner slot 17. There is a possibility that a useless space may be formed in the part. According to the configuration of FIGS. 4 and 5, such a point can be improved.

  4 and 5, a distributed winding coil 60a in which the axial length of the coil end tends to be large is disposed in the outer slot 16, but a toroidal winding coil 50a is also disposed in the outer slot 16. Is done. Thereby, since the number of the components of the distributed winding coil 60a arranged in the outer slot 16 can be reduced, an increase in the axial length of the coil end can be suppressed. Further, since the circumferential length of the distributed winding coil in the outer slot 16 can be increased, the amount of current per circumferential length on the outer rotor side can be increased. Thereby, the difference in the amount of current per circumferential length between the inner diameter side and the outer diameter side of the stator can be reduced or eliminated.

  In the configuration shown in FIGS. 4 and 5, a round wire having a circular cross-sectional shape may be used for the toroidal coil 50a. In this case, the space factor of the coil 50a in the inner slot 17 and the outer slot 16 is lower than in the case where a rectangular wire is used for the coil 50a, but the circumferential direction between the inner slot 17 and the first slot portion 18 is lower. Compared to the case where the length is different, the space factor is easily increased.

  In the description of the configuration of FIGS. 4 and 5, the case has been described in which the radial lengths D18 and D17 of both side surfaces in the circumferential direction of the first slot portion 18 and the inner slot 17 are the same. May be different between the first slot portion 18 and the inner slot 17. In this case, of the first slot portion 18 and the inner slot 17, the space factor occupied by the coil 50 a is reduced at the longer radial direction. On the other hand, even in this case, since the circumferential lengths of the first slot portion 18 and the inner slot 17 are the same, the same number of coil components of the coil 50a are arranged in the circumferential direction of the first slot portion 18 and the inner slot 17. Can be placed side by side. For this reason, compared with the case where the circumferential direction length of the 1st slot part 18 and the inner side slot 17 is varied, it is easy to make a space factor high. In this embodiment, other configurations and operations are the same as those in the configuration shown in FIGS. 1 and 2B.

  As mentioned above, although each embodiment of this invention was described, this invention is not limited to each said embodiment, A various deformation | transformation is possible.

  For example, in each of the above embodiments, the coil is distributed winding, but concentrated winding may be used instead of distributed winding.

  10 Stator, 12 Outer teeth, 13 Inner teeth, 14 Stator yoke, 15 Coil, 16 Outer slot, 17 Inner slot, 18 First slot, 19 Second slot, 20 Inner rotor, 30 Outer rotor, 50, 50a Coil (Toroidal winding: first coil), 60, 60a coil (distributed winding: second coil), 100 stator.

Claims (8)

An annular stator having an inner tooth protruding to the inner diameter side and an outer tooth protruding to the outer diameter side;
An inner rotor facing the inner diameter side of the annular stator;
An outer rotor facing the outer diameter side of the annular stator;
A toroidal-wound multi-phase first coil disposed in an inner slot between the inner teeth and an outer slot between the outer teeth;
A second coil of a plurality of phases that is arranged in the outer slot and is supplied with a current in the same timing and in the same direction as the first coil arranged in the same outer slot for each of a plurality of phases;
A motor comprising: An annular stator having an inner tooth protruding to the inner diameter side and an outer tooth protruding to the outer diameter side;
An inner rotor facing the inner diameter side of the annular stator;
An outer rotor facing the outer diameter side of the annular stator;
A toroidal wound three-phase first coil disposed in an inner slot between the inner teeth and an outer slot between the outer teeth;
A three-phase second coil that is arranged in the outer slot and is supplied with current in the same timing and in the same direction as the first coil arranged in the same outer slot for each of the three phases;
A motor comprising:   The motor according to claim 1, wherein the first coil is disposed on an inner diameter side of the outer slot, and the second coil is disposed on an outer diameter side of the outer slot.   The motor according to claim 3, wherein the second coil is a distributed winding or concentrated winding coil.   5. The motor according to claim 1, wherein the inner teeth and the outer teeth are rectangular in cross section and have the same width. The outer slot has a first slot portion on the inner diameter side and a second slot portion on the outer diameter side,
The first slot portion and the inner slot have the same length in the circumferential direction, and the length of the second slot portion in the circumferential direction is larger than the length of the first slot portion in the circumferential direction,
The first coil is disposed in the inner slot and the first slot portion,
The motor according to claim 1, wherein the second coil is disposed in the second slot portion, and the second coil is a distributed winding coil.   The first slot portion and the inner slot have the same length of both side surfaces in the circumferential direction in the radial direction passing through the center in the circumferential direction when viewed from one side in the axial direction. Item 7. The motor according to Item 6.   The motor according to claim 6, wherein the first coil is formed by a rectangular wire having a rectangular cross-sectional shape.

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