CN1463065A - Permanent-magnet rotary dynamo and compressor using same - Google Patents

Abstract

The present invention provides a permanent magnet type rotating electrical machine, by providing a stator with an armature winding (9) of concentrated winding around teeth (10) in a plurality of slots (13) formed on a stator core (12) (7); and in the permanent magnet type rotating electrical machine (11) of the rotor (1) that is loaded with permanent magnet (3) in a plurality of permanent magnet insertion holes (14) that are formed on the rotor core (2), set The magnetic pole angle of the rotor core is fixed within an electrical angle range of 100 degrees to 120 degrees, and recesses are formed between poles on the outer peripheral surface of the rotor core to achieve high output power and low noise.

Description

Permanent magnet type rotating electric machine and compressor using it

technical field

The present invention relates to a permanent magnet type rotating electrical machine in which a permanent magnet for a magnetic field is disposed in a rotor, and more particularly to a permanent magnet type rotating electrical machine installed in a compressor of an air conditioner, refrigerator, or freezer.

Background technique

Conventionally, such permanent magnet type rotating electric machines have been adopted in various shapes. For example, the permanent magnet type rotating electrical machine described in Japanese Unexamined Patent Application Publication No. 2001-218404 has a stator wound with an armature winding of a concentrated winding of a plurality of teeth formed on a stator core and an armature winding formed on a rotor core. A plurality of permanent magnets are inserted into the holes of the permanent magnet rotor, so that it can effectively generate magnetic torque, thereby increasing the output power of the rotating electrical machine.

However, although the above-mentioned prior art focuses only on increasing the output power of the rotating electric machine, it cannot be put into practical use as a rotating electric machine without considering the problem of noise. There are pulsating torque, electromagnetic vibration boosting force, etc. as the main causes of the noise increase of the permanent magnet type rotating electrical machine, but it is effective to reduce the gap magnetic flux density in order to reduce these effects. However, simply enlarging the gap to reduce the gap magnetic flux density will reduce the magnetic flux generated by the permanent magnet due to the increase in the reluctance, so the magnetic torque will decrease and the output power will decrease. Therefore, only the magnetic flux that causes noise should be reduced while increasing the magnetic flux of the magnetic torque.

Contents of the invention

The purpose of the present invention is to provide a permanent magnet type rotating electrical machine which can increase the output power and reduce the noise.

In order to achieve the stated purpose, the permanent magnet type rotating electrical machine of the present invention includes a stator in which armature windings are arranged in multiple slots formed on the stator core; a plurality of permanent magnet insertion holes formed on the rotor core are installed A rotor with permanent magnets embedded; the magnetic pole angle of the rotor core is set within the electrical angle range from 100 degrees to 120 degrees, and recesses are formed between poles on the outer peripheral surface of the rotor core.

The present invention also provides a permanent magnet type rotating electrical machine, which is characterized in that: a stator including armature windings with concentrated windings surrounding the teeth is arranged in a plurality of slots formed on the stator core; multiple slots formed on the rotor core A rotor with permanent magnets is installed in a permanent magnet insertion hole; the magnetic pole angle of the rotor core is set to be approximately the same as the slot pitch of the stator core, and recesses are formed between poles on the outer peripheral surface of the rotor core.

The present invention also provides a permanent magnet type rotating electrical machine, which is characterized in that: a stator including armature windings with concentrated windings surrounding the teeth is arranged in a plurality of slots formed on the stator core; multiple slots formed on the rotor core A rotor with permanent magnets is loaded into a permanent magnet insertion hole; the top shape of the teeth of the stator core is formed into a combined shape of an arc-shaped part and a linear part, which is the magnetic pole angle of the rotor core and the stator. The groove pitch of the core is substantially the same to form recesses between the poles on the outer peripheral surface of the rotor core.

In addition, the present invention also provides a permanent magnet type rotating electrical machine, which is characterized in that: the stator includes a plurality of slots formed on the stator core to provide the armature windings of the concentrated windings surrounding the teeth; A rotor with permanent magnets is installed in a plurality of permanent magnet insertion holes; the ratio of the number of poles of the rotor to the number of slots of the stator is 2:3, and the magnetic pole angle of the rotor is set at 100 degrees to 120 degrees Within an electrical angle range of , recesses are formed between poles on the outer peripheral surface of the rotor core.

In addition, the present invention also provides a permanent magnet type rotating electrical machine, which is characterized in that: the stator includes a plurality of slots formed on the stator core to provide the armature windings of the concentrated windings surrounding the teeth; A rotor with permanent magnets is installed in a plurality of permanent magnet insertion holes; the ratio of the number of poles of the rotor to the number of slots of the stator is 2:3, and the shape of the tops of the teeth of the stator core is formed into an arc shape A combined shape of a portion and a linear portion, and recesses are formed between poles on the outer peripheral surface of the rotor core so that the magnetic pole angle of the rotor core falls within an electrical angle range of 100° to 120°.

Through various tests, it is found that in order to increase the output power of the permanent magnet rotating machine and reduce the noise, it is only necessary to increase the magnetic flux of the permanent magnet to generate the magnetic torque and reduce the armature reaction flux. Here, since the armature reaction flux generally advances at an electrical angle of approximately 90 degrees with respect to the permanent magnet flux, it is only necessary to reduce the The inductance generated by the coupling of the windings is sufficient.

Based on the test results, the present invention forms recesses between the poles (on the q-axis side) on the outer peripheral surface of the rotor core so that the magnetic pole angle of the rotor core is within the range of 100 degrees to 120 degrees electrical angle. At the same time, the magnetic flux of the interlinked permanent magnets can reduce the inductance of the axis of abscissa, so the armature reaction flux can be reduced. Therefore, it is possible to provide a permanent magnet type rotating electrical machine capable of reducing noise while increasing output power.

Description of drawings

Fig. 1 is a cross-sectional view showing a radial cross-sectional shape of Embodiment 1 using a permanent magnet type rotating electrical machine of the present invention.

FIG. 2 is a cross-sectional view showing an enlarged radial cross-sectional shape of the rotor in FIG. 1 .

Fig. 3 is a cross-sectional view showing an enlarged radial cross-sectional shape of a rotor according to Embodiment 2 of the permanent magnet type rotating electrical machine of the present invention.

Fig. 4 is a cross-sectional view showing an enlarged radial cross-sectional shape of a rotor according to Embodiment 2 of the permanent magnet type rotating electrical machine of the present invention.

Fig. 5 is a cross-sectional view showing an enlarged radial cross-sectional shape of a rotor according to Embodiment 3 of the permanent magnet type rotating electric machine of the present invention.

Fig. 6 is a cross-sectional view showing an enlarged radial cross-sectional shape of a rotor according to Embodiment 4 of the permanent magnet type rotating electric machine of the present invention.

Fig. 7 is a cross-sectional view showing an enlarged radial cross-sectional shape of a rotor according to Embodiment 4 of the permanent magnet type rotating electric machine of the present invention.

Fig. 8 is a cross-sectional view showing a radial cross-sectional shape of Embodiment 5 employing the permanent magnet type rotating electric machine of the present invention.

Fig. 9 is a cross-sectional view showing a radial cross-sectional shape of Embodiment 6 employing the permanent magnet type rotating electric machine of the present invention.

10 is a sectional view showing a radial sectional shape of a permanent magnet type rotating electrical machine of a comparative example.

Fig. 11 is a characteristic diagram showing the permanent magnet type rotating electric machine of the first embodiment.

Fig. 12 is a characteristic diagram showing the permanent magnet type rotating electric machine of the second embodiment.

Fig. 13 is a sectional view showing a compressor according to the present invention.

In the figure: 1-rotor, 2-rotor core, 3-permanent magnet, 4-gap, 6-rotating shaft fitting hole, 7-stator, 8-core back, 9-armature winding, 10-teeth, 11-Permanent magnet rotating motor, 12-Stator core, 13-Slot, 14-Permanent magnet insertion hole, 15-Concave part of rotor core, 17-Fixed scroll part, 18, 21-End plate, 19, 22-Cover plate , 20-rotating scroll member, 23-fitting hole, 24-compression chamber, 25-discharge port, 26-bracket, 27-compression container, 28-discharge pipe, 29-oil retention part, 30-oil hole, 31 - plain bearings.

Detailed ways

Hereinafter, the embodiments of the present invention will be described in detail with reference to FIGS. 1 to 13 . In each figure, the same symbol represents the same component. In addition, what is shown here is about a 4-pole permanent magnet type rotating electrical machine.

(Example 1)

Fig. 1 shows a radial cross-sectional shape of a permanent magnet type rotating electrical machine according to Embodiment 1 of the present invention. In the drawing, a permanent magnet type rotating electrical machine 11 is composed of a stator 7 and a rotor 1 . The stator 7 has a stator core 12 composed of teeth 10 and a core back 8, and an armature winding 9 of a concentrated winding around the teeth 10 in a slot 13 between the teeth 10 (the three-phase winding consists of a U-phase winding 9a , V-phase winding 9b, W-phase winding composition). Here, since the permanent magnet type rotating electrical machine 11 has 4 poles and 6 slots, the electrical angle of the slot pitch is 120 degrees.

Fig. 2 is an enlarged radial sectional shape diagram of the rotor according to Embodiment 1 of the present invention. The rotor 1 is composed of a permanent magnet 3 inserted into a straight permanent magnet insertion hole 14 formed in the rotor core 2, a rotating shaft (not shown), and a rotating shaft hole 6 for fitting. Here, the axis of the rotor 1 extending toward the center of the magnetic poles is defined as the d-axis, and the axis extending toward the center of the magnetic poles and between the magnetic poles at an electrical angle of 90 degrees is defined as the q-axis. In FIG. 2 , the shape of the interpole (q-axis) side of the outer peripheral surface of the rotor core 2 is formed into a concave shape (combined into two slightly V-shaped concave parts), so that the magnetic pole angle θ1 of the rotor core 2 is approximately equal to the slot pitch. .

Fig. 10 is a radial cross-sectional view of a rotor of a comparative example. When the permanent magnet 3 is embedded in the rotor core 2, since the magnetic flux of the permanent magnet 3 is likely to be short-circuited, a recessed shape is also formed on the outer peripheral surface of the rotor core 2 (in the direction of the q axis) of the comparative example to prevent magnetism. short circuit and increase the torque of the magnet flux. However, since the purpose of forming the recess shape between the poles is to prevent short-circuiting of the magnetic flux of the magnet, the recess 15 is made parallel to the side surface of the permanent magnet insertion hole 14 .

However, the permanent magnet type rotating electric machine 11 for driving the compressor, which is the object of improvement of the present invention, always has a problem of noise. The main causes of the increase in the noise of the permanent magnet type rotating electrical machine 11 include pulsating torque and electromagnetic vibration boosting force. To reduce these effects, it is only necessary to reduce the gap magnetic flux density. However, simply enlarging the gap to reduce the gap magnetic flux density will increase the reluctance and reduce the magnetic flux generated by the permanent magnet, so the magnetic torque will decrease and the output power will decrease. Therefore, it has been found through various experiments that only the armature reaction flux, which is the main cause of noise generation, should be reduced without reducing the permanent magnet flux that generates magnetic torque. Here, since the armature reaction flux generally advances at an electrical angle of approximately 90 degrees with respect to the permanent magnet flux, it is only necessary to reduce the inductance on the axis of abscissa (q-axis).

Fig. 11 is a characteristic diagram showing a magnetic pole angle θ1 with respect to a permanent magnet type rotating electrical machine. The axis of abscissa is the magnetic pole angle θ1 expressed in electrical angle, and the axis of ordinate is the induction when the induced electromotive force and the inductance of the axis of abscissa are normalized to 1.0p.u. Electromotive force and inductance on the abscissa axis. Here, the induced electromotive force is proportional to the time change (d/dt) of the interlinkage flux  of the armature winding 9, so the increase or decrease of the permanent magnet flux useful for generating magnetic torque can be judged by the magnitude of the induced electromotive force .

As can be seen from FIG. 11 , the smaller the magnetic pole angle θ1, the larger the gap (void) portion, so the inductance on the axis of abscissa decreases, but hardly changes when θ1=120 degrees or less. Therefore, in order to achieve low noise, it is advisable to make θ1 as small as possible, especially preferably below θ1=120 degrees.

On the other hand, when θ1 is about 80 degrees or more, the induced electromotive force becomes larger than that of the comparative example, and when θ1 is about 80 degrees or less, it is smaller than the conventional motor. Although the induced electromotive force is proportional to the time change of the interlinked magnetic flux of the armature winding 9, in the case of the concentrated winding, the armature winding 9 surrounding the teeth 10 is installed, so the magnetic flux flowing into the teeth 10 becomes the same as that of the armature. Magnetic flux interlinked by the windings. For the permanent magnet type rotating electrical machine 11 that the number ratio of the number of poles of the permanent magnet 3 and the slot 13 is 2:3, because the slot pitch is an electrical angle of 120 degrees, if the magnetic pole angle θ1 is substantially consistent with the slot pitch, then the The magnetic flux of the permanent magnet 3 is effectively utilized. Therefore, θ1 becomes maximum at 120 degrees, and θ1 hardly changes in the range of 100 degrees to 140 degrees.

As mentioned above, if the magnetic pole angle θ1 is set in the range of about 100 degrees to 120 degrees, the output power of the motor can be increased and the noise reduction can also be achieved.

(Example 2)

3 and 4 are cross-sectional views showing enlarged radial cross-sectional shapes of the rotor of Embodiment 2 of the permanent magnet type rotating electrical machine of the present invention. The difference between Example 2 in FIGS. 3 and 4 and Example 1 in FIG. 2 is that gaps 4 are provided at the magnetic poles of rotor core 2 . In addition, in FIG. 3 , the magnetic pole portion of the rotor 1 is symmetrically provided with two gaps 4 with respect to the d-axis, but in FIG. 4 there is one gap 4 on the d-axis.

FIG. 12 is a characteristic diagram showing an angle θ2 with respect to the gap between the magnetic pole portions of the rotor of the permanent magnet type rotating electric machine. The axis of abscissa is the angle θ2 between the gaps 4 expressed in electrical angle, the axis of ordinate is the induced electromotive force and the abscissa when the inductance of the axis of abscissa is normalized to 1.0 p.u. shaft inductance. Therefore, the larger θ2 is, the closer the gap portion 4 is to the interpole (q-axis), and the smaller θ2 is, the closer the gap portion 4 is to the magnetic pole center. Here, when θ2=0 degrees, as shown in FIG. 4 , there is one gap 4 on the d-axis, and the width W2 of the gap 4 becomes twice W1 (W2=2×W1). And, when the magnetic pole angle is taken as a certain value of θ1=120 degrees, it can be seen from Figure 11 that the result is that θ1=120 degrees without the gap 4, the induced electromotive force is 1.06p.u., and the abscissa axis inductance is 0.83p.u. .

The induced electromotive force is slightly reduced by the provision of the gap portion 4, and tends to decrease as the angle θ2 decreases, but is still larger than that of the comparative example. On the other hand, the inductance on the axis of abscissa becomes smaller due to the provision of the gap portion 4, and decreases remarkably as the angle θ2 decreases. Therefore, on the basis of setting the magnetic pole angle θ1 in the range from about 100 to 120 degrees, when the gap 4 is provided in the magnetic pole portion of the rotor 1, the output power can be higher than that of the comparative example and the noise can be reduced. Furthermore, from the standpoint of reducing noise, it is preferable to provide the gap portion 4 at the center of the magnetic pole (on the d-axis).

(Example 3)

Fig. 5 is a sectional view showing a radial sectional shape of an enlarged rotor 1 according to Embodiment 3 of the permanent magnet type rotating electrical machine of the present invention. The difference between Embodiment 3 in FIG. 5 and Embodiment 1 in FIG. 2 is that the shape of the permanent magnet 3 is V-shaped. The present embodiment 3 can obtain the same effect as that of the embodiment 1 in FIG. 2 .

(Example 4)

6 and 7 are cross-sectional views showing the radial cross-sectional shape of an enlarged rotor 1 according to Embodiment 4 of the permanent magnet type rotating electric machine of the present invention. Embodiment 4 in FIGS. 6 and 7 differs from Embodiment 3 in FIG. 5 in that gaps 4 are provided on the magnetic poles of rotor core 2 . In addition, in FIG. 6 , two gaps 4 are provided on the magnetic pole portion of the rotor 1 so as to be symmetrical to the d-axis, while in FIG. 7 one gap 4 is provided on the d-axis.

On the basis of setting the magnetic pole angle θ1 in the range from about 100 to 120 degrees, when the gap part 4 is provided, the magnetic flux of the permanent magnet 3 can be effectively used, and the inductance of the axis of abscissa can be reduced. , so the purpose of low noise can be achieved while the output power of the motor is increased. Furthermore, from the standpoint of reducing noise, the gap portion 4 is finally provided at the position of the center of the magnetic pole (on the d-axis).

(Example 5)

Fig. 8 is a cross-sectional view showing the cross-sectional shape of Embodiment 5 of the permanent magnet type rotating electrical machine according to the present invention. Embodiment 5 shown in FIG. 8 differs from Embodiment 1 shown in FIG. 1 in that the tip of the stator tooth 10 is formed into a shape composed of a circular arc portion and a straight portion.

With such a structure, since the gap length at the end of the tip of the tooth 10 becomes large, the concentration of magnetic flux at the end of the tip of the tooth 10 is relieved, and the pulsating torque is reduced.

Therefore, the noise can be significantly reduced by adopting the cooperation of the rotor 1 shown in the first embodiment and the fourth embodiment.

(Example 6)

Fig. 9 is a cross-sectional view showing the cross-sectional shape of Embodiment 6 of the permanent magnet type rotating electric machine according to the present invention. The difference between Embodiment 6 shown in FIG. 9 and Embodiment 1 and Embodiment 5 is that the armature winding 9 is installed in the slot 13 in the order of U-phase winding 9a, V-phase winding 9b, and W-phase winding 9c. winding.

In the case where there is such a difference in the winding method of the armature winding 9, due to the use of the matching method of the rotor 1 shown in Embodiment 1 and Embodiment 4, the magnetic flux of the permanent magnet 3 can be effectively used, and the The inductance of the axis of abscissa can be reduced, so while the output power of the motor is increased, the purpose of low noise can be achieved.

(Example 7)

Fig. 13 is a sectional view showing a sectional structure of a compressor according to the present invention. The compressor meshes with the centrifugal cover pole 19 erected on the end plate 18 of the fixed scroll member 17 and the centrifugal cover plate 22 erected on the end plate 21 of the orbiting scroll part 20, and relies on the crankshaft 23 to make the orbiting scroll The shape member 20 rotates to perform the compressing action. Among the compression chambers 24 (24a, 24b...) formed by the fixed scroll member 17 and the orbiting scroll member 20, the compression chamber located at the outermost diameter moves toward the center of the two scroll members 17, 20 along with the rotational motion. In the center, the volume gradually decreases. When the compression chambers 24a, 24b reach the vicinity of the centers of the two scroll members 17, 20, the compressed gas in the two compression chambers 24 is discharged from the discharge port 25 communicating with the compression chambers. The discharged compressed gas reaches the compression vessel 27 at the lower part of the support 26 through the gas channel (not shown) provided on the fixed rotating part 17 and the support 26, and is discharged out of the compressor from the discharge pipe 28 provided on the side of the compression vessel 27. In addition, in this compressor, a permanent magnet type rotating electrical machine 11 is installed in the pressure vessel, and it rotates at a rotational speed controlled by an inverter (not shown) installed separately to perform a compression operation. Here, the driving motor is a permanent magnet type rotating electrical machine 11 composed of a stator 7 and a rotor 1 .

Compressors are used as driving sources for air conditioners, refrigerators, and cold storages, and they operate continuously throughout the year, so they are the most important products for preventing global warming and saving energy. When a permanent magnet type rotating electrical machine is used as the driving source, although the purpose of saving energy is achieved due to the high efficiency of the rotating electrical machine, it cannot be used if the noise is large. However, when the permanent magnet type rotating electrical machine of the present invention is used as a driving source, since the noise is low, environmental problems can be solved, so a compressor capable of achieving high efficiency and energy saving can be provided.

As described above, according to the present invention, for the purpose of improving the induced electromotive force of the permanent magnet type motor, since the abscissa axis inductance is reduced, a high output and low noise permanent magnet type rotating electrical machine can be provided.

If the present invention is adopted, a compressor with low noise can also be provided.

Claims (10)

1. a permanent-magnet rotary electric machine is characterized in that: comprise

The stator of armature winding is set in a plurality of grooves on being formed on stator core;

Insert in the hole and be incorporated with the rotor of permanent magnet being formed on a plurality of permanent magnets in the rotor core;

The magnetic pole angle of setting described rotor core is being spent in the electric angle scopes of 120 degree from 100,

Interpolar at the outer peripheral face of described rotor core is formed with recess.

2. a permanent-magnet rotary electric machine is characterized in that: comprise

The stator of the armature winding of the concentrated winding that centers on teeth is set in a plurality of grooves on being formed on stator core;

Insert in the hole and be incorporated with the rotor of permanent magnet being formed on a plurality of permanent magnets in the rotor core;

The slot pitch of setting the magnetic pole angle of described rotor core and described stator core is roughly the same,

Interpolar at described rotor core outer peripheral face is formed with recess.

3. a permanent-magnet rotary electric machine is characterized in that: comprise

The stator of the armature winding of the concentrated winding that centers on teeth is set in a plurality of grooves on being formed on stator core;

Insert in the hole and be incorporated with the rotor of permanent magnet being formed on a plurality of permanent magnets in the rotor core;

The end shape of the teeth of described stator core is formed circular arc shaped portion and linear combined shaped partly,

Be that the magnetic pole angle of described rotor core and the slot pitch of described stator core form recess at the interpolar of described rotor core outer peripheral face roughly the samely.

4. a permanent-magnet rotary electric machine is characterized in that: comprise

The stator of the armature winding of the concentrated winding that centers on teeth is set in a plurality of grooves on being formed on stator core;

Insert in the hole and be incorporated with the rotor of permanent magnet being formed on a plurality of permanent magnets in the rotor core;

The number of poles of described rotor is 2: 3 with the ratio of the groove number of described stator,

Set the magnetic pole angle of described rotor and spend in the electric angle scope of 120 degree 100,

Interpolar at the outer peripheral face of described rotor core is formed with recess.

5. a permanent-magnet rotary electric machine is characterized in that: comprise

The stator of the armature winding of the concentrated winding that centers on teeth is set in a plurality of grooves on being formed on stator core;

Insert in the hole and be incorporated with the rotor of permanent magnet being formed on a plurality of permanent magnets in the rotor core;

The number of poles of described rotor is 2: 3 with the ratio of the groove number of described stator,

The teeth end shape of described stator core is formed the combined shaped of circular arc shaped portion and linear part, and form recess at the interpolar of the outer peripheral face of described rotor core 100 for the magnetic pole angle that makes described rotor core with spending in the electric angle scopes of 120 degree.

6. according to any described permanent-magnet rotary electric machine in the claim 1 to 5, it is characterized in that:

The shape of recess of interpolar that is formed on the outer peripheral face of described rotor core is the recess that is combined by a plurality of shapes that slightly are in the shape of the letter V.

7. according to any described permanent-magnet rotary electric machine in the claim 1 to 6, it is characterized in that:

The shape that is embedded in the permanent magnet of described rotor core is V word or the in-line shape that is projection with respect to described armature spindle.

8. according to any described permanent-magnet rotary electric machine in the claim 1 to 7, it is characterized in that:

The recess shapes of interpolar that is formed on the outer peripheral face of described rotor core is that circumferential lengths at outer peripheral face is than long in the circumferential lengths of described rotor inner headed face.

9. according to any described permanent-magnet rotary electric machine in the claim 1 to 8, it is characterized in that:

1 gap of extending in diametric(al) is set on the magnetic pole piece of described rotor core at least.

10. compressor is characterized in that:

Any described permanent-magnet rotary electric machine in the claim 1 to 9 as drive source.

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