CN114552836A

CN114552836A - Rotating electrical machine

Info

Publication number: CN114552836A
Application number: CN202111312732.0A
Authority: CN
Inventors: 长谷川祐; 石上孝
Original assignee: Hitachi Ltd
Current assignee: Hitachi Ltd
Priority date: 2020-11-10
Filing date: 2021-11-08
Publication date: 2022-05-27
Also published as: JP2022076731A

Abstract

The invention provides a rotating electrical machine, which can reduce the number of main pole slots while maintaining output under the condition of applying an auxiliary pole to a fractional slot winding structure. The motor has a stator (10) and a rotor (20) opposed to the stator (10). The rotor (20) includes a plurality of permanent magnets (122) arranged along the circumference of the rotor core (120). The stator (10) includes a plurality of teeth extending from a cylindrical stator yoke (114) toward the rotor (20) and a plurality of slots (104) formed between the plurality of teeth. Of the teeth, main pole teeth (116) wound with coils and auxiliary pole teeth (118) not wound with coils are alternately arranged in the circumferential direction. The rotating electric machine (100) is configured in such a manner that the greatest common divisor of the total number S of slots (104) and the number P of poles, which is the total number of permanent magnets (122), is G, the number X of adjacent continuous coils, which is S/M/G relative to the number M of phases, is 1, and all coils are wound in the same direction.

Description

Rotating electrical machine

Technical Field

The present invention relates to a rotating electric machine.

Background

As a background art in this field, for example, patent document 1 is known. Patent document 1 describes a brushless motor including a rotor and a stator, wherein a plurality of pairs of permanent magnet poles are arranged on an outer periphery of the rotor in a circumferential direction, and a plurality of teeth are arranged on an inner periphery of the stator in the circumferential direction, the plurality of teeth including leg portions protruding inward in an inner diameter direction and claw portions protruding from distal ends of the leg portions. The teeth of the brushless motor are composed of main pole teeth wound with a coil and auxiliary pole teeth not wound with the coil, and the foot parts of the main pole teeth are composed to be lower in iron loss than the auxiliary pole teeth.

The following problems are solved by the above configuration: "when coils are wound around all the teeth in the circumferential direction, the coils wound around different teeth are adjacently arranged in one slot, and considering insulation between the coils, winding work of the coils, and the like, it is necessary to reduce the volume occupancy of the coils in the slots, and such a configuration has a problem in forming a high-output, high-torque brushless motor. "

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open No. 2006-340511

Disclosure of Invention

Technical problem to be solved by the invention

Motors that are low speed and require greater torque tend to increase the radius of rotation. When a more compact size is required, since thinning is achieved in the motor by suppressing the increase of the coil end, it is easy to select concentrated windings. In addition, in order to improve the winding coefficient of the concentrated winding motor and reduce the cogging torque, a fractional-slot winding structure is adopted, in which the number Q of slots per pole per phase is 0.5 or less.

The ratio of the fractional slot winding structure to the number of slots to the number of poles of the concentrated winding motor is 3: the general combination structure of 2 is likely to increase the torque, but the number of slots is increased relative to the number of poles, so that the number of manufacturing steps is increased in proportion to the number of coils, which is problematic.

When this problem is solved by the structure of patent document 1, the following problem occurs with respect to a motor of a specific fractional slot winding structure.

For example, fig. 4 is a cross-sectional view of a general three-phase 6-slot 8-pole motor cut in a direction perpendicular to the axial direction. The letters and symbols in fig. 4 indicate the winding directions of the respective phases (U-phase, V-phase, W-phase) and windings, adjacent teeth 401 are all different phases, and armature windings 402 are all wound in the same direction. Eight permanent magnets 403 are arranged in the rotor. In the configuration shown in fig. 4, as described in patent document 1, it is not possible to alternately arrange any of adjacent in-phase windings as auxiliary poles.

Fig. 5 is a cross-sectional view of a general three-phase 9-slot 8-pole motor cut in a direction perpendicular to the axial direction. As shown in fig. 5, the windings of the respective phases (U-phase, V-phase, W-phase) are adjacent and continuous over three

teeth

401a, 401b, 401 c. In the configuration shown in fig. 5, when the main poles and the auxiliary poles are alternately arranged in the same phase as described in patent document 1, since the two auxiliary poles are continuous in the circumferential direction, an unnecessary space is generated between the auxiliary pole of one phase and the auxiliary pole of the other phase.

An object of the present invention is to provide a rotating electrical machine capable of reducing the total number of main pole teeth while maintaining output in a state where an auxiliary pole is applied to a fractional slot winding structure.

Means for solving the problems

In order to achieve the above object, a rotary electric machine of the present invention includes a stator, and a rotor opposed to the stator, the rotating electrical machine is characterized in that the rotor is composed of a cylindrical rotor core and a plurality of permanent magnets arranged in alternating orientations along the circumference of the rotor core, the stator is composed of a cylindrical stator yoke, a plurality of teeth extending from the stator yoke to the rotor, and a plurality of slots formed between the plurality of teeth, in the teeth, main pole teeth wound with coils and auxiliary pole teeth not wound with coils are alternately arranged in a circumferential direction, the greatest common divisor of the total number S of slots and the number P of poles, which is the total number of the permanent magnets, is G, the number X of adjacent continuous coils, which is S/M/G relative to the number M of phases, is 1, and all the coils are wound in the same direction.

A rotating electrical machine according to the present invention includes a stator and a rotor facing the stator, the rotor including a cylindrical rotor core and a plurality of permanent magnets arranged in an alternating direction along a circumference of the rotor core, the stator including a cylindrical stator yoke, a plurality of teeth extending from the stator yoke to the rotor, and a plurality of slots formed between the plurality of teeth, wherein a main pole tooth on which a coil is wound and an auxiliary pole tooth on which the coil is not wound are alternately arranged in the circumferential direction in the teeth, a maximum common divisor of a total number S of the slots and a number P of poles that is the total number of the permanent magnets is G, a number X of adjacent continuous coils that is S/M/G with respect to a phase number M is an odd number greater than 1 and is a prime number, and in the above case, N obtained by dividing the total number S of the slots by the number X of the adjacent continuous coils is set as the total number of the main pole teeth (N: (where N is a total number of the main pole teeth: (N) N ═ S/X), all the coils are wound in the same direction.

Effects of the invention

According to the present invention, it is possible to provide a rotating electrical machine capable of reducing the total number of main pole teeth while maintaining output in a state where an auxiliary pole is applied to a fractional slot winding structure.

Drawings

Fig. 1 is an overall configuration diagram of a rotating electric machine (motor) according to embodiment 1 of the present invention.

Fig. 2 is a diagram showing a structure inside the stator housing 5 in fig. 1.

Fig. 3 is a cross-sectional view of a stator and a rotor of example 1 of the present invention cut in a direction orthogonal to the rotation axis direction.

Fig. 4 is a cross-sectional view of a general three-phase 6-slot 8-pole motor cut in a direction perpendicular to the axial direction.

Fig. 5 is a cross-sectional view of a general three-phase 9-slot 8-pole motor cut in a direction perpendicular to the axial direction.

Fig. 6 is a comparative diagram comparing magnetomotive force distributions of the motor of example 1 and a 9-slot 8-pole motor.

Fig. 7 is an overall configuration diagram of a rotating electric machine (motor) according to embodiment 2 of the present invention.

Fig. 8 is a diagram showing a structure inside the stator housing 6 in fig. 7.

Detailed Description

Hereinafter, embodiments of the present invention will be described with reference to the drawings. The same components are denoted by the same reference numerals, and the same description is not repeated.

The various components of the present invention do not necessarily have to be present independently, and it is permissible for one component to be constituted by a plurality of members, for a plurality of components to be constituted by one member, for one component to be a part of another component, or for a part of one component to be overlapped with a part of another component, or the like.

[ example 1]

Fig. 1 is an overall configuration diagram of a rotating electric machine (motor) according to embodiment 1 of the present invention. Fig. 1 is a cross-sectional view taken along the direction of the rotation axis of the rotating electric machine. The rotating electrical machine of embodiment 1 is a configuration example of a three-phase alternating-current motor having three coils and eight permanent magnets.

As shown in fig. 1, the rotating electric machine 100 includes a stator 10, a rotor 20 rotatably supported on a radially inner side of the stator 10, a rotating shaft 4 fixed to the rotor 20, and a stator housing 5 covering the stator 10 and the rotor 20. The rotor 20 is disposed to face the stator 10 through a gap 102 (air gap). The stator 10 includes an armature winding 112, and the armature winding 112 is wound around main pole teeth described later. The rotor 20 has permanent magnets 122 adhered to a rotor core described later.

Fig. 2 is a diagram showing a structure inside the stator housing 5 in fig. 1. Fig. 2 is a cross-sectional view of the rotating electric machine taken along a direction orthogonal to the direction of the rotation axis.

In fig. 2, the rotor 20 rotates about the rotation shaft 4. In the following description, unless otherwise specified, the expressions "inner periphery side" and "outer periphery side" respectively indicate a side closer to the center of the rotation shaft and a side farther from the center of the rotation shaft. The expression "radial direction" indicates a linear direction perpendicular to the rotation shaft 4, and the expression "circumferential direction" indicates a rotation direction of the rotation shaft 4.

As shown in fig. 2, rotor 20 includes rotor core 120 made of a magnetic material, and rotating shaft 4 penetrating rotor core 120 and rotating together with rotor core 120. Further, the rotor 20 includes a plurality of (8 in fig. 2) permanent magnets 122. Each permanent magnet 122 is adhered to the surface of the rotor core 120 with the magnetization center facing the gap 102, alternately forming magnetic poles of N and S poles. In embodiment 1, permanent magnets 122 are bonded to be housed in the grooves on the outer peripheral side of rotor core 120, but the method of configuring the magnetic poles by arranging the permanent magnets with respect to the present invention is not limited to this. For example, the magnetic poles may be configured by a method of providing magnet insertion holes in the interior of the rotor core 120 and embedding permanent magnets in the magnet insertion holes.

The stator 10 includes a stator core 110 made of a magnetic material. The stator core 110 is composed of a cylindrical stator yoke 114, a plurality of main pole teeth 116 and a plurality of auxiliary pole teeth 118 that are located on the inner circumferential side of the stator yoke 114 and face the rotor 20. The main pole teeth 116 and the auxiliary pole teeth 118 are alternately arranged along the circumferential direction of the stator yoke 114. A plurality of slots 104 are formed between the plurality of teeth (main teeth 116, auxiliary teeth 118).

The armature winding 112 is formed into a coil of an arbitrary shape and wound around the main pole teeth 116. Armature winding 112 is not wound around auxiliary pole teeth 118.

Conductors

112A and 112B are arranged in the space (slot 104) between adjacent main pole teeth 116 and auxiliary pole teeth 118. The

conductors

112A and 112B are part of the armature winding 112. The armature winding 112 is, for example, a copper wire in which an insulating film (e.g., a paint coat, engineering plastic, or the like) is coated on an electric conductor mainly composed of copper. The conductor 112A and the conductor 112B are composed of one or more copper wires, and are energized oppositely to each other in the rotation axis direction when the rotating electric machine 100 is driven. In the present embodiment 1, in order to enhance insulation, a spacer (e.g., a tape of a non-combustible material, or a resinous bobbin, etc.) may be sandwiched between the armature winding 112 and the main pole teeth 116. Further, the armature winding 112 may be fixed to the main pole teeth 116 by dipping the stator 10 in varnish, resin, or the like. In the present embodiment 1, the number of main pole teeth 116 is three, and the number of auxiliary pole teeth 118 is three. The main pole teeth 116 and the auxiliary pole teeth 118 are alternately arranged in the circumferential direction of the stator yoke 114, and the armature windings 112 wound around the main pole teeth 116 are all wound in the same direction.

The magnet material of the permanent magnet 122 may be any of ferrite, neodymium, samarium-cobalt, and the like. The permanent magnet 122 of embodiment 1 has a tile shape in the cross section of fig. 2, but is not limited thereto, and may have a flat plate shape. Further, the permanent magnet of each 1 magnetic pole may be divided into a plurality in the radial or circumferential direction.

As the magnetic body constituting rotor core 120, a laminate in which magnetic steel plates and electrical insulators are laminated is used in order to reduce eddy current loss generated in rotor core 120. In order to reduce the material cost and the processing cost, a solid (block) magnetic body may be used. The rotor core 120 is fixed to the rotary shaft 4 by bonding, welding, press-fitting, shrink-fitting, or the like.

As the magnetic body constituting stator core 110, a laminate in which magnetic steel plates and electrical insulators are laminated is used in order to reduce eddy current loss generated in stator core 110. In order to reduce the material cost and the processing cost, a solid (block) magnetic body may be used.

Fig. 3 is a sectional view of a stator and a rotor of example 1 of the present invention, cut in a direction orthogonal to the direction of the rotation axis. As shown in fig. 3, the number of copper wires constituting the

conductors

112A and 112B adjacent to the main pole teeth 116 is determined according to the number of turns of the armature winding 112.

When a three-phase alternating current is supplied to the armature winding 112, a magnetic field generated by excitation of the

adjacent conductors

112A and 112B acts on the main pole teeth 116U wound around the U-phase armature winding 112, and a magnetic circuit 108U indicated by a dotted arrow is formed on the main pole teeth 116U. Similarly, a magnetic path 108V indicated by a broken-line arrow is formed in main pole tooth 116V, and a magnetic path 108W indicated by a broken-line arrow is formed in main pole tooth 116W.

In fig. 3, when the number of turns of the armature winding 112 is one for each of the main pole teeth 116, the number of copper wires constituting the conductor 112A and the conductor 112B is one, respectively. When a three-phase alternating current of amplitude 1A (ampere) is supplied and the U-phase peaks, the magnetomotive force of the magnetic circuit in the U-phase main pole tooth 116U becomes 2AT (ampere-turn) magnetomotive force due to the presence of the two same-phase conductors therearound.

Similarly, the magnetic field generated by excitation of the U-phase conductor 112B also acts on the auxiliary pole tooth 118 adjacent to the main pole tooth 116U, and a magnetomotive force of 1AT (2/2) is generated in the auxiliary pole tooth 118.

On the other hand, among the magnetomotive forces of the auxiliary pole teeth 118, a magnetomotive force of 0.5AT (1/2) acts in the opposite direction under the influence of the magnetic circuit 108V or the magnetic circuit 108W generated by the conductor 112B through which currents of different phases (V-phase or W-phase) pass. As a result, since the directions of the magnetic circuit 108U from the U-phase and the magnetic circuit 108V or the magnetic circuit 108W from the out-of-phase are opposite to each other, the magnetomotive force of the auxiliary pole teeth 118UV, 118WU becomes 0.5AT (1-0.5). Therefore, the magnetomotive force of the auxiliary pole teeth 118UV, 118WU becomes one-fourth of the magnetomotive force of the main pole teeth.

Meanwhile, the magnetomotive force of the auxiliary pole tooth 118(118VW) between the V-phase and the W-phase mutually increases, becomes 1AT (0.5+0.5), and becomes one-half of the magnetomotive force of the main pole tooth of the U-phase.

In the motor having 6 slots and 8 poles as in example 1, since all the coils are wound in the same direction, magnetic saturation is less likely to occur inside the auxiliary pole teeth 118, the circumferential width of the auxiliary pole teeth 118 can be made narrower than the circumferential width of the main pole teeth 116, and the magnetomotive force of the main pole teeth can be increased by enlarging the slots 104 into which the armature windings 112 enter.

When the winding direction of the armature windings of the main pole teeth other than the U-phase is changed to the opposite direction, if the magnetomotive force of the main pole teeth of the U-phase is also 2AT, the magnetomotive force of the adjacent auxiliary pole teeth matches the direction in which the magnetomotive forces of the same phase and the different phase increase each other, and therefore 1.5AT (1 +0.5) is obtained. This is three quarters of the main pole tooth. Therefore, the effect of enlarging the groove 104 is small compared to the structure of embodiment 1. Further, the magnetomotive force of the auxiliary pole teeth 118VW between the V-phase and the W-phase acts almost equally in the direction of mutual reinforcement, but since the directions of the magnetic paths are opposite, there is a disadvantage of reducing the torque.

In order to constitute the rotating electric machine 100 of embodiment 1, it is a condition that the number X of adjacent continuous coils is 1, and all the coils are wound in the same direction. The number of adjacent continuous coils X is expressed by the following equation.

X＝S/M/G

(S: total number of cells, M: number of phases, P: number of poles, G: greatest common divisor of S and P)

In rotating electric machine 100 of example 1, the greatest common divisor of the total number of slots S and the number of poles P, which is the total number of permanent magnets, is G, and the number X of adjacent continuous coils, which is S/M/G, is 1 for the number of phases M (three phases of U-phase, V-phase, and W-phase in example 1), and the coils are all wound in the same direction. More specifically, the total number S of slots is 6, the number of poles is 8, and the greatest common divisor thereof is 2, so that the number X of adjacent consecutive coils is 1(X is S/M/G6/3/2), and the coils are all wound in the same direction. Thus, in example 1, the greatest common divisor of the total number of slots S and the number of poles P, which is the total number of permanent magnets, is G, and the number X of adjacent continuous coils, whose phase number M is S/M/G, is 1, and the condition that all coils are wound in the same direction is satisfied.

In the rotating electric machine 100 of example 1, a 6-slot and 8-pole motor is used, but the present invention can also provide similar effects to a concentrated winding motor in which the total number of slots is S and the number of poles (total number of permanent magnets) is P, by using a fractional slot structure in which the number of slots per pole and phase Q obtained by S/3/P is less than 0.5 when the number of phases is 3. In general, the number of slots per pole per phase Q can be sub-calculated by the following equation.

Q＝S/(M·P)＝S/M/P

(S: total number of cells, M: number of phases, P: number of poles)

For example, in the case of a 9-slot 8-pole motor shown in fig. 5, when the main pole and the auxiliary poles are alternately arranged in the same phase, since the two auxiliary poles are continuous in the circumferential direction, an unnecessary space is generated between the auxiliary pole of one phase and the auxiliary pole of the other phase. For a 9 slot, 8 pole motor, the method of calculating the total number of main pole teeth N and the total number of auxiliary pole teeth is as follows.

The number of slots per pole Q of a motor having 3, 9, 8 slots and 8 poles is 0.375 in terms of S/M/P9/3/8, and the number of slots per pole is less than 0.5.

The greatest common divisor G of the total number S (9) of slots and the number P (8) of poles is 1. The number of adjacent continuous coils X is S/M/G9/3/1 is 3. The number X of adjacent consecutive coils is an odd number greater than 1 and is a prime number.

Then, the total number of main pole teeth N and the total number of auxiliary pole teeth are calculated. The total number N of main pole teeth is a value obtained by dividing the total number S of slots by the number X of adjacent continuous coils, and can be calculated by the following equation.

N＝S/X

(S: total number of slots, X: number of adjacent continuous coils)

When the total number N of the main teeth is calculated according to the above equation, N is S/X9/3 is 3, and the total number N of the main teeth is 3. The total number of the auxiliary pole teeth is 3, and the number of the auxiliary pole teeth is the same as the total number N of the main pole teeth. Thus, the 9 slot 8 pole motor of fig. 5 is shown in a state that it can be transformed into a 6 slot 8 pole motor of fig. 1 and 2.

Fig. 6 is a graph comparing magnetomotive force distributions of the motor of example 1 and a 9-slot 8-pole motor. In fig. 6, the number of turns of the armature winding and the current are equal.

Here, the number of turns of the armature winding in each tooth of the 9-slot 8-pole motor is set to 1, and in the 6-slot 8-pole motor of example 1, the number of turns of the armature winding of the main pole tooth is set to 3 (the number obtained by collecting 3 teeth) based on the number X of adjacent continuous coils. Although the magnetic field generated in the main pole tooth of embodiment 1 becomes simply 3 times, the width of the auxiliary pole tooth can be reduced to, for example, one half based on the magnitude of the magnetomotive force, and thus the design is easily changed by enlarging the width of this part of the main pole tooth to prevent magnetic saturation from occurring.

Here, when the amplitude of the three-phase alternating current is 1A, the magnetomotive force distribution of the U-phase at the U-phase peak is derived as shown in fig. 6. In this distribution, if the effective value of the fundamental wave that affects the motor torque is calculated, the effective value of the fundamental wave is 1.3 times as large as that of the conventional one, and the torque can be increased while the number of coils is reduced. If the torques are equal, the motor can be driven with a smaller current, and thus the electric power of the motor can be saved.

The rotating electric machine 100 according to example 1 is characterized in that the greatest common divisor of the total number of slots S and the number of poles P, which is the total number of permanent magnets, is G, the number X of adjacent continuous coils, whose phase number M is S/M/G, is 1, and all the coils are wound in the same direction. In addition, in the rotating electric machine 100 according to example 1, when the number X of adjacent continuous coils is an odd number larger than 1 and is a prime number, N obtained by dividing the total number S of slots by the number X of adjacent continuous coils is set as the total number of main pole teeth (N ═ S/X).

[ example 2]

Next, embodiment 2 of the present invention will be described with reference to fig. 7 and 8. Embodiment 2 is different from embodiment 1 in that embodiment 2 is an external rotor type motor in which a rotor 40 is formed on the outer peripheral side of a stator 30.

For example, there is a 36-slot 32-pole motor in which the total number of slots S is 36 and the number of poles P is 32. The windings of the respective phases (U-phase, V-phase, W-phase) are wound around 3 teeth adjacently. In the case of this motor, according to the formula shown in embodiment 1, the number of slots per phase per pole is Q/M/P36/3/32 is 0.375. The number of slots per phase per pole is a value less than 0.5.

The greatest common divisor G of the total number S (36) of the slots and the number P (32) of poles is 4. The number of adjacent continuous coils X is S/M/G36/3/4 is 3. The number X of adjacent consecutive coils is an odd number larger than 1 and is a prime number.

Then, the total number of main pole teeth N and the total number of auxiliary pole teeth are calculated. According to the formula shown in embodiment 1, the total number N of the main pole teeth is 12, and S/X36/3 is 12. The total number of the auxiliary pole teeth is 12, and the number of the auxiliary pole teeth is the same as the number of the main pole teeth N. Thus, the motor showing 36 slots 32 poles can be modified to the structure of the 24 slots 32 poles motor shown in fig. 7 and the drawings.

The rotating electric machine 200 of embodiment 2 is an example of a 24-slot 32-pole three-phase ac motor. Fig. 7 is an overall configuration diagram of a rotating electric machine (motor) according to embodiment 2 of the present invention. The same structures as those of embodiment 1 are given the same reference numerals, and detailed description thereof is omitted.

As shown in fig. 7, the rotary electric machine 200 includes a stator 30, a rotor 40 rotatably supported radially outside the stator 30, a rotor case 6 covering the rotor 40, and a rotary shaft 4 fixed to the rotor case 6. In embodiment 2, the rotor case 6 does not necessarily cover the entire rotor 40, and if the rotor case 6 is configured as a member for fixedly connecting the rotary shaft 4 and the rotor 40, a fixing method of the rotor 40 and the rotor case 6 is not limited.

The rotor 40 is opposed to the stator 30 by a gap 202. The stator 30 includes an armature winding 212 (

conductors

212A, 212B) wound around the main pole teeth. The rotor 40 includes permanent magnets 222 adhered to the rotor core.

Fig. 8 is a diagram showing a structure inside the stator housing 6 in fig. 7. Fig. 8 is a sectional view of the rotating electric machine cut in a direction orthogonal to the rotation axis direction.

As shown in fig. 8, the rotor 40 is constituted by a rotor core 220 made of a magnetic body and a plurality of permanent magnets 222 adhered to the surface of the rotor core 220. Each permanent magnet 222 is adhered to the inner peripheral surface of the rotor core 220 with the magnetization center facing the gap 202, and alternately forms magnetic poles of N and S poles.

The stator 30 is constituted by a stator core 210, main pole teeth 216, and auxiliary pole teeth 218. The auxiliary teeth 218 are provided with auxiliary tooth tip claws 219 extending in the circumferential direction from the outer circumferential tooth tips.

With the structure of the present embodiment, the effect described in embodiment 1 can be obtained, and the tooth profile is formed into a shape that is open in the radial direction by adopting the rotor-externally-fitted type, so that the auxiliary pole tooth tip claw can be configured without interfering with the region of the coil disposed in the slot. Therefore, the auxiliary tooth tip claw smoothes the distribution of the permeance (the reciprocal of the magnetic resistance) on the gap surface, and can suppress torque ripple caused by the magnetic flux of the permanent magnet when the motor rotates. Further, since the magnetic path formed by the claw of the leading end of the auxiliary pole tooth is generated, it is possible to obtain an effect of increasing the magnetic flux of the permanent magnet acting on the torque and improving the motor torque.

The present invention is not limited to the above-described embodiments, and various modifications are also included. The above-described embodiments are described in detail for easy understanding of the present invention, but are not necessarily limited to include all the structures described.

Description of the reference symbols

100. 200 … rotary electric machine, 2 … stator housing, 4 … rotating shaft, 6 … rotor housing, 10, 30 … stator, 20, 40 … rotor, 102, 202 … gap, 104 … slot, 108 … magnetic circuit, 110, 210 … stator core, 112, 212 … armature winding, 112A, 112B, 212A, 212B … conductor, 114, 214 … stator yoke, 116U, 116V, 216 … main pole tooth, 118UV, 118VW, 118WU, 218 … auxiliary pole tooth, 120, 220 … rotor core, 122, 222 permanent magnet 222 …, 219 … auxiliary pole tooth front end claw.

Claims

1. A rotary electric machine including a stator, and a rotor opposing the stator, the rotary electric machine being characterized in that,

the rotor is composed of a cylindrical rotor core and a plurality of permanent magnets arranged in alternating orientations along the circumference of the rotor core,

the stator is composed of a cylindrical stator yoke, a plurality of teeth extending from the stator yoke to the rotor, and a plurality of slots formed between the plurality of teeth,

the teeth are arranged such that main pole teeth on which coils are wound and auxiliary pole teeth on which the coils are not wound are alternately arranged in the circumferential direction,

the greatest common divisor of the total number S of the slots and the number P of poles, which is the total number of the permanent magnets, is G, the number X of adjacent continuous coils, the number M of which is S/M/G, is 1, and all the coils are wound in the same direction.

2. The rotating electric machine according to claim 1,

the number of phases is three phases of U phase, V phase and W phase, and the number Q of slots per pole and phase calculated by S/3/P is less than 0.5.

3. The rotating electric machine according to claim 1,

the width of the main pole teeth in the circumferential direction is larger than the width of the auxiliary pole teeth in the circumferential direction.

4. The rotating electric machine according to claim 1,

the rotating electric machine has a structure of a rotor external type.

5. The rotating electric machine according to claim 4,

the front end of the auxiliary pole tooth extends along the circumferential direction.

6. A rotary electric machine including a stator, and a rotor opposing the stator, the rotary electric machine being characterized in that,

the teeth are arranged such that a main pole tooth on which a coil is wound and an auxiliary pole tooth on which the coil is not wound are alternately arranged in a circumferential direction,

in the case where the greatest common divisor of the total number S of the slots and the number P of poles, which is the total number of the permanent magnets, is G, and the number X of adjacent continuous coils, which is S/M/G with respect to the number M of phases, is an odd number greater than 1 and is a prime number, N, which is obtained by dividing the total number S of the slots by the number X of adjacent continuous coils, is the total number of the main pole teeth (N is S/X), and all the coils are wound in the same direction.

7. The rotating electric machine according to claim 6,

the total number of the auxiliary pole teeth is the same as the total number N of the main pole teeth.