JP2002101629A - Permanent magnet rotating electric machine - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a permanent magnet rotary electric machine which has excellent efficiency. SOLUTION: In the permanent magnet rotary electric machine which is constituted of a stator which has an armature winding within a plurality of slots which are formed in a stator core, permanent magnets which are disposed on the yoke of the stator core and a rotor which has projection parts each of which is formed by protruding a part of the yoke between the respective permanent magnets, the permanent magnets are magnetized in parallel in the direction which is parallel to a center line from the rotor of the permanent magnets and the armature winding is composed of a concentrated winding.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent magnet type rotating electric machine having a rotor core having a plurality of permanent magnets.

[0002]

2. Description of the Related Art Conventionally, for example, see Japanese Patent Application Laid-Open No. 1-286758.
In the publication, a protrusion formed by projecting a part of the rotor core in the outer circumferential direction is provided between a plurality of permanent magnets provided on the rotor core, and the width A of the protrusion and the stator slot pitch are provided. It is described that by giving a relationship of A = (n + 0.5) B with n as an integer between B and B, the cogging torque can be reduced and the characteristics can be improved by using reluctance torque.

[0003]

Problems to be solved for the permanent magnet type rotating electric machine include high efficiency, low vibration and low noise. Means for achieving high efficiency include reducing loss components generated in the machine, that is, reducing copper loss, iron loss, mechanical loss, and stray loss, and improving main magnetic flux torque and reluctance torque. . It is considered that the above-described prior art utilizes this reluctance torque.

On the other hand, in the above case, the inventors of the present invention provide a protrusion formed by projecting a part of the rotor core in the outer peripheral direction, and when the magnetic flux of the magnet leaks through the protrusion, the magnet torque is rather reduced. Was found to tend to decrease. Also,
The present inventors have found that the above case is an effective technique mainly for the case where the armature windings are distributed windings, and that when applied to concentrated windings, the magnet torque is further reduced.

An object of the present invention is to provide a permanent magnet type rotating electric machine which suppresses a decrease in magnet torque and has excellent efficiency characteristics.

[0006]

SUMMARY OF THE INVENTION A feature of the present invention is that a stator having an armature winding in a plurality of slots formed in a stator core, and a permanent magnet disposed in a yoke portion of the rotor core, A rotor having a projection formed by projecting a part of the yoke between the permanent magnets, wherein the permanent magnet has a center line of the permanent magnet from the rotor. The armature winding has a parallel magnetization direction, and the armature winding is formed by concentrated winding.

Another feature of the present invention is that a permanent magnet is arranged in a stator having an armature winding in a plurality of slots formed in the stator core, and a permanent magnet is arranged in a yoke portion of the rotor core. A rotor having projections formed by projecting a part of the yoke between magnets, wherein the permanent magnets are attached to a center line of the permanent magnets gathered from a center line of the rotor. A magnetic direction, and the armature winding is formed by concentrated winding.

The present inventors have found that when a concentrated winding armature winding is applied to the prior art, the coil end length can be shortened because the coil is wound directly on the stator teeth, and the armature winding resistance is reduced. Although it was possible to reduce the copper loss and to reduce the copper loss, it was found that the concentrated winding reduces the magnetic flux linked to the winding. In addition, the present inventors provide a protrusion in the prior art, whereby the magnetic flux of the magnet leaks to the protrusion and the magnet torque is reduced. As a result, they have found that the advantages of concentrated winding cannot be used effectively.

On the other hand, as in the present invention, for example, by setting the magnetization of the permanent magnet to be parallel to the center line from the rotor of the permanent magnet, the leakage of the magnet flux to the protruding portion is prevented. Since the magnet flux can be effectively collected even when concentrated winding is used for the armature winding, it is possible to provide a permanent magnet type rotating electric machine having good efficiency characteristics. The above and other features of the invention are described further below.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below with reference to FIGS.

FIG. 1 is a radial sectional view of a permanent magnet type rotating electric machine according to one embodiment of the present invention, and FIG. 2 is an enlarged view of a rotor of the permanent magnet type rotating electric machine according to one embodiment of the present invention. 1 shows a method of magnetizing a permanent magnet according to one embodiment of the present invention. FIG. 19 shows a magnetizing method of the comparative technique.

1, 2, 17 and 19, a stator 1 has a concentrated winding armature winding 5 (U-phase winding 5A, V-phase winding) in a plurality of slots 3 formed in a stator core 2. Line 5B, W
(Distributed winding of the phase winding 5C).

The rotor 6 includes a plurality of permanent magnets 7 (shown with four poles in this figure) arranged in the circumferential direction via projections 8 projecting in the rotor radial direction, and a radial direction of the permanent magnet 7. It comprises a piece 9 provided on the protruding portion 8 to prevent scattering to the shaft, and a shaft hole 10 for fitting to a shaft (not shown).

The projection 8 is formed such that the relationship between the width Wo on the outer diameter side of the rotor and the width Wi on the inner diameter side is Wo> Wi.

The permanent magnet 7 is formed in an arc shape in which the center point of the inner diameter r1 is o and the center point of the outer diameter r1 'is o'. Here, the position of the center point o 'of the outer diameter r1' is the outer diameter r
1 'is in contact with the inner diameter r0 of the piece 9, and the maximum outer diameter rm is arranged to be equal to the maximum outer diameter r of the projection 8.

The permanent magnet 7 is magnetized so that the direction of the magnetic flux is parallel to the rotor center line 11 (not shown).
The angle is adjusted. That is, for example, a permanent magnet having a fixed magnetization direction (in this case, parallel magnetization) is created by binding the magnetic material powder together with a binder in a magnetic field (here, in a parallel magnetic field). Here, the angle between the rotor center line 11 and the magnetic domain is shown as 0 ° in an ideal state in FIG. 17, but in consideration of manufacturing tolerance,
It is desirable to be within ± 1 °.

In FIG. 19, the permanent magnet 7 is magnetized so as to be oriented in the same direction as the rotor center line 11 in the circumferential direction, so that the magnet leaks to the adjacent magnet of different polarity via the projection 8. Leakage magnetic flux 12 is generated. As a result, the magnet magnetic flux that passes through the teeth 4 and interlinks with the concentrated winding armature winding 5 is reduced, which causes deterioration of characteristics.

In the present invention, since the permanent magnet 7 is magnetized in parallel with the rotor center line 11, the magnetic flux can be efficiently collected in the teeth 4, so that the problem of the comparative technique is reduced. It is possible to provide a permanent magnet type rotating electric machine with good characteristics.

FIGS. 3 and 4 show a radial cross section of a permanent magnet type rotating electric machine according to another embodiment of the present invention and an enlarged view of a rotor of the permanent magnet type rotating electric machine according to one embodiment of the present invention. ,
1 and 2 are denoted by the same reference numerals.

In FIGS. 3 and 4, a portion different from those in FIGS. 1 and 2 is that the position of the center point o 'of the outer diameter r1' in the permanent magnet 7 is the same as the outer diameter r1 '. The point is that it is disposed so as to be in contact with r0 and the maximum outer diameter rm is equal to or larger than the maximum outer diameter r of the projection 8.

With this configuration, the same effects as those in FIGS. 1 and 2 can be obtained, and the distribution of the magnet magnetic flux in the gap can be made closer to a sine waveform than in the configuration shown in FIGS. And excellent characteristics can be obtained.

FIGS. 5 to 8 show a radial cross section of a permanent magnet type rotating electric machine according to another embodiment of the present invention and an enlarged view of a rotor of the permanent magnet type rotating electric machine according to one embodiment of the present invention. ,
1 to 4 are denoted by the same reference numerals.

5 to 8, the parts different from those in FIGS. 1 to 4 are different from those in FIGS.
The point is that i and Wo are equal.

With such a configuration, the same effect as in the case of FIGS. 1 to 4 can be obtained, and the width of the projection 8 can be made wider than in the case of FIGS. 1 to 4, so that the reluctance torque can be reduced. More can be obtained, and the characteristics can be improved.

FIGS. 9 to 16 are radial sectional views of a permanent magnet type rotating electric machine according to another embodiment of the present invention and enlarged views of the rotor of the permanent magnet type rotating electric machine according to another embodiment of the present invention. The same components as those shown in FIGS. 1 to 8 are denoted by the same reference numerals.

In FIGS. 9 to 16, a portion different from those in FIGS. 1 to 8 is formed by extending the piece 9 in the circumferential direction so as to be flush with the maximum outer diameter r of the projection 8. There is in the point.

With such a configuration, friction loss and cavitation between the piece 9 and air or fluid can be suppressed even when operating at tens of thousands of revolutions per minute, which is effective in reducing mechanical loss and reducing wind Noise can be reduced.

Further, since the cross-sectional area of the magnetic path of the projection 8 is equivalently increased, more reluctance torque can be obtained and the characteristics can be improved.

FIG. 18 shows a method of magnetizing a permanent magnet according to another embodiment of the present invention. In FIG. 18, the magnetic domain of the permanent magnet 7 is adjusted such that the magnetic flux is concentrated on the rotor center line 11 toward the outer periphery, and the magnet is subjected to polar orientation magnetization.

In the embodiment described above, the permanent magnet 7 is magnetized so that the magnetic flux is parallel to the rotor center line 11, but the same effect can be obtained by applying the magnetizing method shown in FIG. As a result, more magnet magnetic flux can be collected in the teeth 4, so that the characteristics can be further improved.

As described in detail above, according to one embodiment of the present invention, the permanent magnet is magnetized in parallel with the center line of the permanent magnet from the rotor, so that the magnet is magnetized. Since the leakage of the magnetic flux to the projecting portion can be reduced, and the magnet magnetic flux can be effectively collected even when the concentrated winding is used for the armature winding, a permanent magnet type rotating electric machine having good efficiency characteristics can be provided.

[0032]

According to the present invention, it is possible to provide a permanent magnet type rotating electric machine having good efficiency characteristics.

[Brief description of the drawings]

FIG. 1 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to one embodiment of the present invention.

FIG. 2 is an enlarged view of a rotor of the permanent magnet type rotating electric machine according to one embodiment of the present invention.

FIG. 3 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 4 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 5 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 6 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 7 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 8 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 9 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 10 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 11 is a diagram showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 12 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 13 is a view showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 14 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 15 is a view showing a radial cross-sectional shape of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 16 is an enlarged view of a rotor of a permanent magnet type rotating electric machine according to another embodiment of the present invention.

FIG. 17 is a diagram showing a method of magnetizing a permanent magnet according to one embodiment of the present invention.

FIG. 18 is a view illustrating a method of magnetizing a permanent magnet according to another embodiment of the present invention.

FIG. 19 is a diagram showing a magnetizing method of a comparative technique.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Stator, 2 ... Stator iron core, 3 ... Slot, 4 ... Teeth, 5 ... Concentrated winding armature winding, 6 ... Rotor, 7 ... Permanent magnet, 8 ... Projection part, 9 ... Single part, 10 ... Shaft holes, 11 ...
Rotor center line.

 ──────────────────────────────────────────────────続 き Continuing from the front page (72) Inventor Tomohiro Okawa 1-1-1, Higashitaga-cho, Hitachi City, Ibaraki Prefecture Inside the Electrification Equipment Division of Hitachi, Ltd. (72) Inventor Mika Takahashi Omikamachi, Hitachi City, Ibaraki Prefecture No. 1-1, Hitachi, Ltd., Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Shinichi Wakai 7-1-1, Omika-cho, Hitachi City, Ibaraki Prefecture F-Term, Hitachi, Ltd. Hitachi Research Laboratory F-term (reference) JK03 5H622 AA03 CA02 CA10 CA13 CB04 PP03 QB01

Claims (8)

[Claims] 1. A stator having an armature winding in a plurality of slots formed in a stator core, a permanent magnet disposed in a yoke portion of a rotor core, and one of the yoke portions disposed between the permanent magnets. A permanent magnet type rotating electric machine comprising: a rotor having a protruding portion formed by projecting a portion, wherein the permanent magnet has a magnetization direction parallel to a center line of the permanent magnet from the rotor, A permanent magnet type rotating electric machine wherein the armature winding is a concentrated winding. 2. A stator having an armature winding in a plurality of slots formed in a stator core, and a permanent magnet disposed in a yoke of a rotor core. A permanent magnet type rotating electric machine comprising: a rotor having a protruding portion formed by projecting a portion, wherein the permanent magnet has a magnetization direction that is gathered at a center line of the permanent magnet from the rotor. A permanent magnet type rotating electric machine wherein the child winding is a concentrated winding. 3. A stator having armature windings in a plurality of slots formed in a stator core, and permanent magnets arranged at equal intervals in a yoke portion of the rotor core, and the yoke is provided between the permanent magnets. A permanent magnet type rotating electric machine comprising: a rotor having a projection part formed by projecting a part of the permanent magnet, wherein the permanent magnet has a magnetization direction parallel to a center line of the permanent magnet from the rotor. A permanent magnet type rotating electric machine characterized in that the armature winding is constituted by concentrated winding. 4. A stator having an armature winding in a plurality of slots formed in a stator core, and permanent magnets arranged at equal intervals in a yoke portion of the rotor core, and the yoke is provided between the permanent magnets. A permanent magnet type rotating electric machine comprising: a rotor having a protrusion formed by projecting a part of the permanent magnet, wherein the permanent magnet has a polar orientation magnetized to be centered on a center line of the permanent magnet from the rotor. A permanent magnet type rotating electric machine characterized in that the armature winding is constituted by concentrated winding. 5. The permanent magnet according to claim 1, wherein an inner peripheral side of the permanent magnet has an arc shape, an outer peripheral side of the permanent magnet has an arc shape, and the stator and the rotating member have the same shape. A permanent magnet type rotating electric machine characterized in that the gap between the daughters is an unequal gap. 6. A permanent magnet type rotating electric machine according to claim 1, wherein a maximum outer diameter of said permanent magnet is larger than a maximum outer diameter of said projection. 7. The permanent magnet type rotating electric machine according to claim 1, wherein the circumferential width of the projection is the same in the radial direction. 8. A permanent magnet type rotating electric machine according to claim 1, wherein a portion extending in the circumferential direction on the outermost peripheral side of said projection is streamlined.