KR20150050464A - Internal permanent magnet motor and compressor with internal permanent magnet motor - Google Patents

Abstract

The present invention provides a motor having an excellent overall balance in consideration with low vibration, high efficiency and rigidity (high rotation), and more specifically, an internal permanent magnet motor and a compressor with the internal permanent magnet motor. The motor comprises: a plurality of teeth formed toward a center shaft at the inner circumference of a yoke in a cylindrical shape and equipped with a stator wound with a coil in distribution winding to a plurality of teeth; and a rotor installed in the inside of the stator, in which a plurality of magnetic poles composed of two permanent magnets disposed in a convex V shape at the center shaft side are formed at same space in the circumferential direction, wherein the rotor includes an outer flux barrier composed of pores formed at an outer end in a direction of diameter of two permanent magnets respectively and an inner flux barrier composed of pores formed at an inner end in a direction of diameter of two permanent magnets respectively, wherein each inner flux barriers of two permanent magnets are connected to each other spatially, whereas flux density of a bridge part formed at an outside of the outer flux barrier in a direction of diameter is set to 1.8 to 1.9 T.

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention [0001] The present invention relates to a compressor having a magnet-embedded type motor and a magnet-

The present invention relates to a compressor having a magnet-embedded motor and a magnet-embedded motor.

Conventionally, a magnet embedded type motor (hereinafter referred to as an IPM motor) using reluctance torque in addition to magnet torque has been used as a high efficiency motor. Reluctance torque is generated by using the d-axis inductance (Ld) and the q-axis inductance (Lq) using the protruding polarity. The permanent magnet is arranged in a V-shape so as to have a salient pole in Ld and Ld . However, simply arranging the permanent magnets in the V-shape results in nonuniformity of the magnetic flux flowing between the magnets and the stator, resulting in an increase in cogging torque, leading to an increase in torque ripple and an increase in vibration at the time of motor driving.

Therefore, in order to lower the cogging torque, as shown in Japanese Patent Application Laid-Open Publication No. 2013-99193, it is possible to change the shape of the rotor or to change the shape of the teeth of the stator as shown in Japanese Patent Application Laid-Open Publication No. 2011-234601, A configuration in which a slit is formed in the rotor as shown in Patent Application Laid-Open Publication No. 2011-101595 can be considered.

Here, in relation to the arrangement of the magnets embedded in the rotor, the cogging torque is often reduced by optimizing the normal pole distance, the magnet spacing constituting each pole, the magnet angle and the magnet length. The most effective means in this case is to change the distance between the stimuli. This is because, as the cogging torque is a pulling force generated between the magnet and the stator, it is necessary to make the magnetic flux flowing through the teeth as uniform as possible.

For example, if the distance between the magnetic poles is too great, the magnetic flux flowing through the teeth becomes nonuniform, and the cogging torque increases. On the other hand, if the distance between the poles is too close, the cogging torque decreases but a short-circuit of the magnetic flux occurs between the magnets and the induced voltage decreases and the motor efficiency drops. For this reason, many analyzes and evaluations are required when determining the distance between the poles, and the motor efficiency deteriorates due to the decrease of the induced voltage by changing the flux flow.

Japanese Patent Application Laid-Open Publication No. 2013-99193 Japanese Patent Application Laid-Open Publication No. 2011-234601 Japanese Patent Application Laid-Open Publication No. 2011-101595

In order to solve the above-described problems, one aspect of the present invention is to propose a compressor having a magnet-embedded type motor and a magnet-embedded type motor excellent in balance in all aspects in consideration of low vibration, high efficiency and rigidity (high rotation).

To this end, a magnet-buried type motor according to an aspect of the present invention includes: a stator having a plurality of teeth formed in a cylindrical inner yoke inner periphery toward a central axis, the plurality of teeth being wound with coils; And a rotor rotatably installed inside the stator, the rotor including a plurality of magnetic poles composed of two permanent magnets formed at regular intervals in the circumferential direction, and the rotor is a gap formed at each of the radially outer ends of the two permanent magnets And an inner flux barrier formed of a gap formed at each radially inner end of the two permanent magnets, wherein each of the inner flux barriers of the two permanent magnets is spatially connected to each other.

The plurality of magnetic poles each include two permanent magnets arranged in a convex V-shape on the central axis.

The rotor further includes a rotor iron core in which a plurality of holes for inserting two permanent magnets are formed along the outer circumference, and the two permanent magnets are gradually separated from each other in the radial direction from the rotation center of the rotor iron core And are arranged in a V-shape.

Further, the magnet embedded type motor according to an aspect of the present invention further includes a bridge portion formed along the outer circumferential surface of the rotor iron core, wherein the bridge portion is formed on the outer side in the radial direction with respect to the outer flux barrier.

The magnetic flux density of the bridge portion depends on the width dimension of the bridge portion, and it is desirable to set the magnetic flux density of the bridge portion to 1.8 to 1.9T.

In the magnet-embedded type motor of the present invention, since the inner flux barriers of the two permanent magnets arranged in a V-shape convex on the central axis are spatially connected to each other, the magnet torque can be maximized. Accordingly, by providing the outer flux barriers at the radially outer ends of the two permanent magnets, and by setting the magnetic flux density of the bridge portion formed outside the outer flux barrier in the radial direction to 1.8 to 1.9 T, the rotor strength and reluctance torque can be improved.

That is, according to the present invention, it is possible to provide a motor excellent in balance in all aspects in consideration of low vibration, high efficiency, and rigidity (high rotation). Specific experimental data will be described later.

Further, the magnet-buried type motor according to one aspect of the present invention has been studied for a configuration (inter-pole distance) for reducing the cogging torque by taking into consideration the relationship between the inter-pole distance and the width dimension of the teeth. The present invention has found that there is a peculiar relationship between the inter-pole distance and the tooth width dimension in the configuration of reducing the cogging torque while suppressing the decrease of the induced voltage.

That is, it is preferable that A = k B (where k is 1.65 to 1.75) is satisfied when the inter-pole distance formed between mutually adjacent magnetic poles is A and the width dimension of the tooth is B, respectively.

As described above, since the inter-pole distance A and the tooth width dimension B satisfy the relation of A = k B (where k is 1.65 to 1.75), the cogging torque can be reduced while suppressing the decrease of the induced voltage. Specific experimental data will be described later.

The inter-pole distance is preferably the width of the magnetic flux path formed between the adjacent outer flux barriers adjacent to each other in the adjacent magnetic poles.

The outer flux barrier includes a first space portion formed on the outer side in the radial direction outer end surface of the permanent magnet along the flat plate direction of the permanent magnet and a second space portion formed on the outer side of the V- .

By doing so, it is possible to change the shape of the outer flux barrier by dividing into the first space portion and the second space portion, and the shape of the bridge portion can also be divided into the first space portion and the second space portion.

The circumferential dimension of the outer end of the outer flux barrier is preferably at least five times the width dimension of the bridge portion.

Further, the opening angle of the permanent magnets arranged in a V-shape is 120 DEG to 100 DEG, and when the V-shaped vertex of the permanent magnet arranged in the V-shape is located on the center line of the tooth, It is preferable that the tooth-line end face nearest to the direction outer end is opposed to the inner portion of the V-shaped permanent magnet on the outer peripheral surface of the rotor.

By doing so, it is possible to secure a region in which the magnetic flux flows into the teeth at the position closest to the radially outer end of the permanent magnet, and the magnetic flux flowing through the plurality of teeth can be made uniform.

In the magnet-embedded type motor according to one aspect of the present invention, it is preferable that the slots formed between the teeth are located at 1.5 to 3 positions relative to adjacent magnetic poles.

By doing so, the slot formed between the teeth is positioned 1.5 to 3 relative to the neighboring magnetic poles, so that the output torque can be increased and the high-speed rotation region can be enlarged. Specific experimental data will be described later.

Further, in the magnet-embedded type motor according to one aspect of the present invention, it is preferable that the radially inner ends of the two permanent magnets constituting the magnetic pole are in close contact with each other.

By doing so, the d-axis inductance Ld is reduced, so that the reluctance torque can be increased and the output torque can be further increased.

Also, an air conditioner and a refrigerating device using a compressor or a compressor having the above-described magnet-embedded type motor can be embodied as an embodiment of the present invention.

According to another aspect of the present invention, there is provided a magnet-embedded motor including: a shaft rotating about a center axis; A stator having a plurality of teeth formed toward a central axis and having a plurality of teeth wound with coils; And a rotor rotatably installed inside the stator, the rotor including a plurality of magnetic poles arranged in a V-shape convex to the central axis at equal intervals in the circumferential direction, the rotor including a plurality of magnet insertion holes A plurality of permanent magnets inserted into the plurality of magnet insertion holes to form a plurality of magnetic poles; an outer flux barrier formed at each of the radially outer ends of the plurality of permanent magnets; And the plurality of permanent magnets are arranged in a V-shape gradually apart from each other as they are radially outward from the center of rotation of the rotor iron core.

The compressor having the proposed magnet embedded type motor and the magnet embedded type motor can provide a motor excellent in balance in all aspects in consideration of low vibration, high efficiency and rigidity (high rotation).

1 is a partial schematic view showing the configuration of a magnet-embedded type motor according to a first embodiment of the present invention.
2 is a partially enlarged cross-sectional view showing a specific shape of the flux barrier according to the first embodiment of the present invention.
3 is a partially enlarged sectional view showing the relationship between the inter-pole distance and the tooth width dimension in the magnet embedding type motor of the present invention.
Fig. 4 is a diagram showing a simulation result of cogging torque when coefficients k = 1.91, 1.7, and 1.45 in the magnet-buried type motor of the present invention.
5 is a diagram showing the relationship between the inter-pole distance (coefficient k), the cogging torque, and the induced voltage increase rate in the magnet-embedded type motor of the present invention.
6 is a magnetic speed at the time of no load in the magnet-embedded type motor according to the first embodiment of the present invention.
Fig. 7 is a diagram showing a simulation result showing the relationship between the width of the bridge portion and the magnetic flux density in the magnet-embedded type motor of the present invention. Fig.
8 is a diagram schematically showing a configuration of a compressor using a magnet-embedded type motor according to a second embodiment of the present invention.
9 is a diagram schematically showing a configuration of a magnet-embedded type motor according to a second embodiment of the present invention.
10 is an enlarged view of a magnet-embedded type motor according to a second embodiment of the present invention.
11 is a diagram showing a correlation between the number of revolutions of the motor and the output torque.
12 is a graph showing the correlation between the number of slots and the output torque, which are relative to magnetic poles.
13 is a view illustrating a refrigeration cycle having a compressor using a magnet-embedded type motor according to a second embodiment of the present invention.
Figs. 14 and 15 are schematic views showing a magnet-embedded type motor, which is a modification of the second embodiment of the present invention.

≪ Embodiment 1 >

Hereinafter, a first embodiment of a magnet-embedded motor according to the present invention will be described in detail with reference to the accompanying drawings.

In the first embodiment, reference numerals are used only in Figs. 1 to 3.

2 is a partially enlarged cross-sectional view showing a specific shape of a flux barrier according to the first embodiment of the present invention, and Fig. 3 is a cross- Sectional enlarged cross-sectional view showing the relationship between the inter-pole distance and the tooth width dimension in the magnet-embedded type motor according to the first embodiment of the present invention.

1, the motor-embedded type motor 100 according to the first embodiment of the present invention is a motor used in, for example, a compressor constituting a refrigeration cycle. The motor-embedded type motor 100 includes a plurality of teeth 22 wound with a stator coil 5 (Rotor) 3 (rotor) provided rotatably in the stator 2, and a rotor shaft 4 (rotor shaft) provided at the rotation center of the rotor 3 . However, electric power is supplied to the stator coil 5 through the lead wire.

1 shows a six-pole motor in which the number of slots is 36 slots and the number of poles is six, but the number of slots is 48 slots and the number of poles is eight.

The stator 2 has a cylindrical yoke 21 and a plurality of teeth 22 formed on the inner circumferential portion of the yoke 21 toward the central axis. The stator coil 5 is wound around the plurality of teeth 22 in a distributed winding manner.

The rotor 3 has a rotor iron core 31 in which a plurality of magnet insertion holes 31H are formed along the outer periphery and a plurality of permanent magnets 3P inserted in the plurality of magnet insertion holes 31H and constituting a plurality of magnetic poles 3P And magnets 32a and 32b.

Specifically, each of the magnetic poles 3P is constituted by a first permanent magnet 32a and a second permanent magnet 32b which are arranged in a convex V-shape on the central axis side as shown in Fig. Specifically, the first permanent magnet 32a and the second permanent magnet 32b are spaced apart from each other in a V-shape so as to be gradually spaced apart from the rotation center of the rotor core 31 in the radial direction.

The opening angle (magnet angle) of the first permanent magnet 32a and the second permanent magnet 32b in the first embodiment of the present invention is configured to be in the range of 100 ° to 120 °.

However, the magnet insertion hole 31H formed in the rotor core 31 is formed in a V-shape so as to be gradually spaced apart from the center of rotation of the rotor core 31 toward the outside in the radial direction.

The first permanent magnet 32a has a flat plate shape, and an outer flux barrier 6a1 and an inner flux barrier 6a2 are formed in the radially outer end portion and the radially inner end portion of the first permanent magnet 32a. The outer flux barrier 6a1 and the inner flux barrier 6a2 are formed by the same space as the magnet insertion hole 31H and are formed by inserting the first permanent magnet 32a into the magnet insertion hole 31H.

The shape of the outer flux barrier 6a1 formed at the radially outer end of the first permanent magnet 32a is the same as the shape of the outer permanent magnet 32a of the permanent magnet 32a from the radially outer end face of the first permanent magnet 32a, A first space portion 6a11 formed on the outer side in the direction of the flat plate and a bridge portion 33 formed along the outer peripheral surface of the rotor iron core 31 are formed so as to have the same width dimension as the first permanent magnet 32a, And a second space portion 6a12 formed in the second space portion 6b.

The width dimension of the bridge portion 33 of the first embodiment of the present invention is configured to be, for example, in the range of 0.3 mm to 1.2 mm. The width dimension of the second space portion 6a12 formed outside the V-shaped portion of the first permanent magnet 32a is, for example, in the range of 0.0 mm to 1.0 mm. In addition, the circumferential dimension of the outer end of the outer flux barrier 6a1 is configured to be five or more times the width dimension of the bridge portion 33. [

A fixing protrusion 35 for fixing the first permanent magnet 32a is formed in the first space portion 6a11 of the magnet insertion hole 31H. The height dimension of the fixing protrusion 35 is set to be at least small in a range in which the first permanent magnet 32a can be fixed in order to reduce the d-axis inductance Ld. In order to make Ld smaller, the area of the first space portion 6a11 is increased by at least decreasing. The height dimension is determined based on the dimensional tolerance of the magnet insertion hole 31H and the dimensional tolerance of the first permanent magnet 32a, and may be 0.3 mm, for example. The width dimension of the fastening protrusion 35 is set to be somewhat large, for example, 1 mm so as to secure the rigidity for receiving the centrifugal force of the first permanent magnet 32a. Describing this width dimension, if the value is made smaller, the rigidity can not be ensured. On the other hand, if the value is too large, the d-axis inductance Ld becomes too large.

The second permanent magnets 32b are formed in the same plate shape as the first permanent magnets 32a and have an outer flux barrier 6b1 and an inner flux barrier 6b2 made of voids at the radially outer end and the radially inner end, Is formed. The outer flux barrier 6b1 and the inner flux barrier 6b2 are formed in the same space as the magnet insertion hole 31H and are formed by inserting the second permanent magnet 32b into the magnet insertion hole 31H. An outer flux barrier 6a1 and an inner flux barrier 6a2 formed at both ends of the first permanent magnet 32a and an outer flux barrier 6b1 formed at both ends of the second permanent magnet 32b and an inner flux barrier 6b2 formed at both ends of the first permanent magnet 32a, Have the same shape.

In the first embodiment of the present invention, the inner flux barrier 6a2 of the first permanent magnet 32a and the inner flux barrier 6b2 of the second permanent magnet 32b are spatially connected to each other. That is, the inner flux barrier 6a2 and the inner flux barrier 6b2 are formed as a single space.

In the magnet-embedded type motor 100 of the first embodiment of the present invention, as shown in Fig. 3, the inter-pole distance formed between adjacent magnetic poles 3P is A and the width dimension of the tooth 22 is B (Where k is in the range of 1.65 to 1.75) when A = k < B >

Here, the inter-pole distance A is the width dimension of the magnetic flux path formed between adjacent magnetic poles 3P. More specifically, the distance between adjacent magnetic poles 3P is the width of the first permanent magnet 32a of one magnetic pole 3P Is the width dimension of the magnetic flux passage formed between the flux barrier 6a1 formed at the radially outer end and the flux barrier 6b1 formed at the radially outer end of the second permanent magnet 32b of the other magnetic pole 3P.

In the magnetic embedding type motor 100 of the first embodiment of the present invention, the V-shaped vertex of the permanent magnets 32a and 32b arranged in a V-shape is positioned on the center line of the tooth 22 The distal end face 22a of the tooth 22 at the position closest to the respective radially outer ends of the first permanent magnet 32a and the second permanent magnet 32b in the state of V (V-shaped inner side portion) of the permanent magnets 32a and 32b arranged in a letter shape (see Fig. 3). Thus, a region in which the magnetic flux flows into the teeth 22 closest to the radially outer ends of the permanent magnets 32a and 32b is secured to make the magnetic fluxes flowing through the plurality of teeth 22 uniform.

Next, FIG. 4 shows the simulation results of the cogging torque when the coefficients k of the magnet-embedded type motor 100 according to the first embodiment of the present invention are set to 1.91, 1.7, and 1.45.

FIG. 4 is a graph showing a simulation result of the cogging torque when the coefficients k = 1.91, 1.7 and 1.45 in the magnet-embedded type motor of the present invention. FIG. Torque and an induced voltage rise rate.

Fig. 5 shows the simulation results of the cogging torque and the induced voltage increase rate when the coefficient k (inter-pole distance) is changed in Fig.

In this simulation, the opening angle of the first permanent magnet and the second permanent magnet is 120 °, the width dimension of the bridge portion is 0.8 mm, the width dimension of the second space portion is 1.0 mm, the width dimension of the fixing projection is 1.0 mm, The height dimension of the projection is 0.3 mm.

4 and 5, when the inter-stimulus distance A is reduced, the cogging torque is reduced, but the inter-stimulus distance A is minimized to a predetermined value (k = 1.7) and the inter- If it is smaller, the phase is reversed and becomes larger again.

As can be seen from Fig. 5, when the coefficient k is 1.7, the cogging torque becomes the minimum value and the coefficient k = 1.7 makes the magnetic flux easily flow, and the induced voltage does not decrease. That is, the coefficient k is most preferably 1.7, and may be 1.65 to 1.75 in consideration of unevenness of the mold and the like.

It can be seen from Fig. 5 that the cogging torque depends on the width dimension (B) of the teeth, and the coefficient k is a coefficient for determining the correction width based on the tooth width dimension B for minimizing the cogging torque .

6 shows the magnetic velocity of the magnet-buried type motor 100 with the coefficient k being 1.7 when no load is applied.

6 is a magnetic speed at the time of no load in the magnet-embedded type motor according to the first embodiment of the present invention.

In Fig. 6, it can be seen that there is no short-circuit of the magnetic fluxes between the mutually adjacent magnetic poles, that is, between the first permanent magnet 32a of one magnetic pole and the second permanent magnet 32b of the other magnetic pole.

It can also be seen that the magnetic flux sufficiently flows into the tooth magnetic flux nearest to the radially outer end of the permanent magnets 32a and 32b.

In the configuration in which the inner flux barriers 6a2 and the inner flux barriers 6b2 are spatially connected, that is, in the configuration in which there is no center rib between the two permanent magnets 32a and 32b as in the first embodiment of the present invention, two permanent magnets 32a , 32b) are held by the bridge portion (33). That is, the bridge portion 33 is configured so that the stress due to the centrifugal force is concentrated.

Here, in the conventional magnet-embedded type motor, magnetic saturation (2.0 ㅁ 0.1T) is used at the radially outer end of the permanent magnets 32a and 32b in order to fully utilize the reluctance torque. However, in order to be magnetically saturated, it is necessary to narrow the bridge portion 33 and it is difficult to ensure rigidity (mechanical strength), so that torque ripple at the time of motor rotation increases and the balance as a motor is not good. In particular, Do.

Next, the magnetic flux density of the bridge portion, the torque ripple, the rigidity (safety factor), the motor output, and the no-load induced voltage when the width dimension of the bridge portion 33 is changed only in the magnet-embedded motor 100 of the first embodiment of the present invention The simulation result is shown in Fig.

Fig. 7 is a diagram showing a simulation result showing the relationship between the width of the bridge portion and the magnetic flux density in the magnet-embedded type motor of the present invention. Fig.

In Fig. 7, only the width dimension of the bridge portion 33 is changed in the configuration of the magnet-embedded type motor 100, and the other shapes and conditions are the same.

The magnetic flux density of the bridge portion 33 is reduced by the reduction of the magnetic resistance of the bridge portion 33 when the width dimension of the bridge portion 33 is from 0.2 mm to 0.8 mm. However, when the width dimension is 0.8 to 1.4 mm, The magnetic flux density tends to increase due to the increase of the leakage flux of the magnets 32a and 32b.

The torque ripple tends to decrease with the reduction of the reluctance torque when the width dimension of the bridge portion 33 is from 0.2 mm to 0.8 mm. However, when the width dimension of the bridge portion 33 is 0.8 mm to 1.4 mm There is a tendency to increase inversely due to an increase in cogging or leakage flux caused by a magnet.

Since the rigidity (safety factor) is proportional to the area of the bridge portion 33, the same is increased proportionally as the width dimension of the bridge portion 33 increases.

However, in the safety factor calculation method, when the width dimension of the bridge portion 33 is 0.8 mm, the breakage is found at 210 Hz with respect to the maximum use frequency 140 Hz. Therefore, the safety factor at the width dimension 0.8 mm of the bridge portion 33 is 1.5 (= 210/140).

The output of the motor is reduced because the reluctance torque and the magnet torque are reduced as the width dimension of the bridge portion 33 increases.

As the width dimension of the bridge portion 33 increases, the no-load induced voltage decreases due to an increase in leakage flux of the permanent magnets 32a and 32b.

As a result, in the region 1 (the region where the width of the bridge portion is less than 0.745 mm and the magnetic flux density is greater than 1.9 T), the motor output is large but the torque ripple is large and the stiffness is difficult to secure.

In the region 3 (the region where the bridge portion width dimension is larger than 0.885 mm and the magnetic flux density is larger than 1.9 T), the magnetic flux density is increased due to magnetic flux concentration due to the short-circuiting of the magnetic fluxes and the rigidity is easily ensured. However, It is a very bad area.

On the other hand, the region 2 (the region where the bridge portion width dimension is 0.745 mm or more and 0.885 mm or less, and the magnetic flux density is 1.9 T or less) is an area where the motor output tends to decrease, but torque ripple is small and stiffness is easily secured. However, the minimum magnetic flux density in the region 2 is 1.87T, and the width dimension of the bridge portion 33 is 0.8mm.

Therefore, by setting or using the magnetic flux density of the bridge portion 33 in the magnet-embedded type motor 100 of the first embodiment of the present invention to be 1.8T to 1.9T, balance of low vibration, high efficiency, and rigidity (high rotation) I can take it.

According to the magnet-embedded motor 100 constructed as described above, since the inner flux barriers 6a2 and 6b2 of the two permanent magnets 32a and 32b, which are arranged in a convex V-shape on the central axis side, are spatially connected to each other, The torque can be maximized. The outer flux barriers 6a1 and 6b1 are provided at the radially outer ends of the two permanent magnets 32a and 32b so that the magnetic flux of the bridge portion 33 formed outside the outer flux barriers 6a1 and 6b1 in the radial direction By setting the density to 1.8 to 1.9 T, the strength and reluctance torque of the rotor 3 can be improved. In other words, it can be a motor with excellent balance in all aspects considering low vibration, high efficiency and rigidity (high rotation).

In addition, since the inter-pole distance A and the tooth width dimension B satisfy the relation of A = k B (where k is 1.65 to 1.75), the cogging torque can be reduced while suppressing the decrease of the induced voltage.

≪ Embodiment 2 >

Hereinafter, a second embodiment of a magnet-buried type motor according to the present invention will be described in detail with reference to the accompanying drawings.

In the second embodiment, reference numerals are used only in Figs. 8 to 15.

Fig. 8 is a schematic view showing a configuration of a compressor using a magnet-embedded type motor according to a second embodiment of the present invention, and Fig. 9 is a schematic view showing the configuration of a magnet- 10 is an enlarged view of a magnet-embedded type motor according to a second embodiment of the present invention.

The magnet-embedded motor 100 according to the second embodiment of the present invention is, as shown in Fig. 8, a permanent magnet synchronous motor used in, for example, a compressor X constituting a refrigeration cycle or the like of an air conditioner.

9, the permanent magnet synchronous motor 100 of the present invention includes a plurality of teeth 22 wound around a stator coil 5 and a plurality of slots 23 formed between the teeth 22, A rotor 3 rotatably installed inside the stator 2 and a rotor shaft 4 provided at the rotation center C of the rotor 3. The rotor 3 is rotatably supported by the stator 2, However, electric power is supplied to the stator coil 5 through the lead wire.

9 shows a motor having a slot number of 36 slots and a number of poles of 6 (for example, a motor having a combination of 6: 1), but may be a motor having 48 slots and 8 poles and a combination of 8: 1 It can be a 9: 1 motor.

The stator 2 has a cylindrical yoke 21 formed by laminating electromagnetic steel plates, a plurality of teeth 22 formed on the inner peripheral portion of the yoke 21 toward the central axis, And has a plurality of slots (23) formed therebetween. In the plurality of teeth 22, for example, a stator coil 5, which is a three-phase coil, is recommended by distribution winding. However, this three-phase coil is configured so that the number of coils of each phase is the same.

The teeth 22 are formed at regular intervals along the circumferential direction, and the shapes of the teeth 22 are all the same. As a result, the slots 23 are equally spaced along the circumferential direction, and the slots 23 have the same shape.

The rotor 3 includes a rotor iron core 31 formed by laminating an electromagnetic steel plate with substantially the same lamination thickness as the stator 2 and having a plurality of magnet insertion holes 31H formed along the outer periphery thereof, 31H and a plurality of permanent magnets 32a, 32b constituting a plurality of magnetic poles 3P.

More specifically, in the rotor 3 of the second embodiment of the present invention, six magnetic poles 3P are formed, and these magnetic poles 3P are arranged at regular intervals along the circumferential direction.

However, in the second embodiment of the present invention, the rotor 3 has a plurality of through holes 33 formed through the rotor iron core 31 in the thickness direction, So that the rotor 3 can be fixed by fitting the pin.

As shown in Figs. 9 and 10, each of the magnetic poles 3P described above is constituted by a first permanent magnet 32a and a second permanent magnet 32b which are convexly arranged in a V-shape on the central axis side .

Specifically, the first permanent magnet 32a and the second permanent magnet 32b are disposed apart from each other in a V-shape so as to be gradually spaced apart from the rotation center C of the rotor core 31 in the radial direction have. The first permanent magnet 32a and the second permanent magnet 32b of the second embodiment of the present invention each have a substantially rectangular parallelepiped shape and the S pole of one permanent magnet 32a or 32b and the other permanent magnet 32b Or 32a are magnetized and contacted with each other at the same time. The opening angle? (Magnet angle) formed by the permanent magnets 32a and 32b is 90 ° <? <160 °. In this embodiment, each permanent magnet 32a and 32b has an opening angle? (32a, 32b) are disposed.

However, the magnet insertion holes 31H formed in the rotor iron core 31 are formed in a V-shape so as to be gradually spaced apart from the rotation center C of the rotor core 31 toward the outside in the radial direction. A fixing protrusion 311 protruding inward from the outer peripheral frame of the magnet insertion hole 31H is formed so as to prevent the permanent magnets 32a and 32b from moving in the magnet insertion hole 31H . Specifically, the fixing protrusions 311 are provided in the magnet insertion hole 31H at positions radially outward of the respective permanent magnets 32a and 32b.

Hereinafter, for the convenience of explanation, when distinguishing the respective magnetic poles 3P, as shown in Figs. 9 and 10, each magnetic pole 3P will be described as a magnetic pole 3P1 to a magnetic pole 3P6.

The first permanent magnet 32a and the second permanent magnet 32b have a flat plate shape, and are a rare-earth magnet or a ferrite magnet whose main component is rare earth. At the radially outer end of the permanent magnets 32a and 32b, a flux barrier 6 made of a gap is formed.

The flux barrier 6 is formed by the same space as the magnet insertion hole 31H and is formed by inserting the first permanent magnet 32a or the second permanent magnet 32b into the magnet insertion hole 31H. However, in this embodiment, the distance between the flux barrier 6 and the outer periphery of the rotor iron core 31 is set to be shorter than the width dimension of the flux barrier 6, and more specifically, set to 1.2 mm or less.

In the permanent magnet synchronous motor 100 of the present embodiment, as shown in Fig. 10, 1.5 to 3 slots 23 are opposed to each other between mutually adjacent magnetic poles 3P.

For example, as shown in Fig. 10, between the adjacent magnetic poles 3P1 and 3P2, the first permanent magnet 32a constituting the magnetic pole 3P1 and the first permanent magnet 32b constituting the magnetic pole 3P2 And corresponds to the space between the second permanent magnets 32b. More specifically, the inter-pole distance L between the magnetic pole 3P1 and the magnetic pole 3P2 is set so that the radial outside corner portion 32a1 of the first permanent magnet 32a and the radial outside corner portion 32b of the second permanent magnet 32b (32b1).

Of course, the inter-pole distance L is the same between the adjacent poles 3P.

The state of the stator 2 is determined based on the above definition so that the rotation center C of the rotor iron core 31 and the center of the magnetic pole 3P (the close contact portion of the first permanent magnet and the second permanent magnet) The permanent magnet synchronous motor 100 of the present embodiment is configured such that 1.5 to 3 slots 23 are positioned relative to each other between adjacent magnetic poles 3P in a state where the center of the slot 23 is located on the line.

More specifically, the permanent magnet synchronous motor 100 of the present embodiment connects, for example, the radial outside corner portions 32a1 of the first permanent magnet 32a constituting the magnetic pole 3P1 with the rotation center C Between the first virtual line B1 and the second imaginary line B2 connecting the rotational center C and the radially outer corner portion 32b1 of the second permanent magnet 32b constituting the magnetic pole 3P2, (23) are located at 1.5 to 3 positions.

Here, although the number of slots 23 opposed to each other between the magnetic pole 3P1 and the magnetic pole 3P2 is described here, it is needless to say that the number of the slots 23 opposed to each other between adjacent magnetic poles 3P same.

Next, the correlation between the number of revolutions of the motor and the output torque when the number of slots arranged relative to the magnetic poles 3P in the permanent magnet synchronous motor 100 of this embodiment is 1.0 (conventional) and 2.5 The results of the simulation are shown in Fig.

Fig. 11 is a diagram showing the correlation between the number of revolutions of the motor and the output torque, and Fig. 12 is a diagram showing the correlation between the number of slots and the output torque relative to the magnetic poles.

11 shows the simulation result of the output torque when the number of slots arranged relative to the magnetic poles 3P is changed from 0.0 to 4.0 in Fig.

However, in this simulation, the opening angle? Of the first permanent magnet 32a and the second permanent magnet 32b is 120 °.

11, when the number of slots arranged relative to the magnetic poles 3P is 2.5 (this time) when the number of slots arranged relative to the magnetic poles 3P is 1.0 (conventional) Torque increases. It can be seen that this tendency becomes remarkable especially as the rotational speed is shifted to the high speed side.

As can be seen from Fig. 5, when the number of slots arranged relative to the magnetic poles 3P is 2.25, the output torque becomes maximum. In other words, the number of slots 23 arranged relative to the magnetic poles 3P is most preferably 2.25, and from the viewpoint of non-uniformity of the mold, it is conceivable that the number of slots 23 is set to 1.5 to 3.0.

Next, a compressor X using the permanent magnet synchronous motor 100 of the second embodiment of the present invention and a refrigeration cycle such as an air conditioner having the compressor X will be described with reference to Figs. 8 and 13 Explain.

13 is a view illustrating a refrigeration cycle having a compressor using a magnet-embedded type motor according to a second embodiment of the present invention.

The refrigeration cycle Y includes an outdoor unit 80 having a compressor X, a condenser 84 and an expansion valve 85 and an indoor unit 81 having an evaporator 86 as shown in FIG.

The refrigeration cycle Y circulates the refrigerant compressed by the compressor X in the order of the compressor X, the condenser 84, the expansion valve 85 and the evaporator 86 in this order so that the refrigerant is circulated between the outdoor unit 80 and the indoor unit 81 So that the cooling function is exerted.

The compressor X includes a compressor 83 and a permanent magnet synchronous motor 100 configured as described above, as shown in Figs.

8, the compression base portion 83 is provided with a spiral wrap 62 (lap) standing upright with the end plate 61 of the fixed scroll member 60 and a single plate 64 of the orbiting scroll member 63 Shaped spiral wraps 65 are formed to mesh with each other and the orbiting scroll member 63 is pivoted to the crankshaft 4 (rotor shaft).

The compression chambers 66a and 66b located on the outermost side of the plurality of compression chambers 66 formed by the fixed scroll member 60 and the orbiting scroll member 63 are moved in the axial direction of the scroll members 60 and 63 Moving toward the center, the volume gradually decreases. When the compression chambers 66a and 66b reach the vicinity of the center of both the scroll members 60 and 63, the compression gas in the compression chambers 66a and 66b is discharged from the main discharge port 67 by communicating with the discharge ports 67. [

The discharged compressed gas reaches the lower portion of the frame 68 in the pressure vessel 69 through a gas passage (not shown) provided in the fixed scroll member 60 and the frame 68, And is discharged through the pipe 70 to the outside of the compressor X.

The permanent magnet synchronous motor 100 having the rotor 3 (rotor) as the stator 2 (stator) is accommodated in the pressure vessel 69 as described above, and is rotated and energized by energizing the three-phase coil do.

A fluid portion 71 is provided below the permanent magnet synchronous motor 100. The oil in the oil portion 71 is supplied to the sliding portion between the orbiting scroll member 63 and the crankshaft 4 (rotor shaft) through the hole 72 provided in the crankshaft 4 (rotor shaft) (Sliding portion), the sliding bearing 73, and the like.

According to the permanent magnet synchronous motor 100 configured as described above, since the slots 23 are located at 1.5 to 3 positions relative to the adjacent magnetic poles 3P, the output torque is increased to enlarge the high- can do.

However, the term &quot; high-speed rotation station &quot; as used herein refers to 20 Hz (rps) to 180 Hz (rps).

In addition, since the first permanent magnet 32a and the second permanent magnet 32b are disposed in close contact with each other, the d-axis inductance Ld is reduced to increase the reluctance torque and further increase the output torque.

In addition, the steel loss can be reduced, and the efficiency can be improved.

In addition, since the inductance can be reduced and the electric time constant is reduced, the transient response is improved.

In addition, the electronic excitation force can be reduced, which reduces noise and vibration.

Further, even when the armature current increases, since the current and the output torque are almost linearly related to each other, the control response is excellent and the application to a compressor or the like is facilitated.

Further, since the compressor X employs the permanent magnet synchronous motor 100 configured as described above as a compressor drive motor, it is possible to realize an expansion of the operation range of the compressor X and a high efficiency.

The refrigeration cycle Y uses the permanent magnet synchronous motor 100 constructed as described above in the compressor constituting the refrigeration cycle Y so that it has a high efficiency performance in a compact operating range and reduces the input, It is possible to reduce the amount of carbon dioxide discharged to the atmosphere.

&Lt; Modification of Second Embodiment >

However, the present invention is not limited to the second embodiment.

For example, in the second embodiment, the magnetic pole 3P is constituted by the first permanent magnet 32a and the second permanent magnet 32b arranged in a V-shape, but as shown in Fig. 14, A single permanent magnet 32c may be arranged so as to be curved toward the outside in the radial direction. Also in this case, it is preferable to change the width dimension of the bridge portion to make the magnetic flux density 1.8 to 1.9 T as in the first embodiment.

In the second embodiment of the present invention, the through hole 33 for penetrating the fixing pin (not shown) is formed in the rotor iron core 31. However, as shown in FIG. 15, A slit hole 34 may be formed in the outer circumferential surface. 15, two slit holes 34 are formed so as to be symmetrical from the through holes 33, but the number of the slit holes 34 is not limited to two.

With this configuration, it is possible to fix the rotor core 31 and limit the flow of magnetic flux generated in the permanent magnets 32a and 32b. In addition, when the permanent magnet synchronous motor 100 is used in the compressor X or the like, the refrigerant passes through the slit hole 34 to cool the stator coil.

In the second embodiment of the present invention, the fixing protrusions 311 are provided in the magnet insertion holes 31H and are provided on the outer side in the radial direction from the permanent magnets 32a and 32b, respectively. However, as shown in Fig. 15, And may be provided on the radially outer side and the radially inner side of the magnets 32a and 32b, respectively.

Further, in the second embodiment of the present invention, the first permanent magnet and the second permanent magnet are in contact with each other at their corners, but they can be arranged such that their end faces are in surface contact with each other, for example.

In the second embodiment of the present invention, the number of the permanent magnets constituting each magnetic pole is two, but the permanent magnets may be composed of three or more permanent magnets.

Further, in the second embodiment of the present invention, the permanent magnet is made of rare earth as a main component, but it may be a bonded magnet.

In the second embodiment of the present invention, the refrigeration cycle used in the air conditioner has been described, but the refrigeration cycle may be used in a refrigerator or a refrigerator.

It should be noted that the present invention is not limited to the first and second embodiments, and includes various modifications that can achieve the same objects and effects as the present invention.

2: stator 3: rotor
3P: Stimulus 21: York
22: tooth 22a: distal end of the tooth
32a: first permanent magnet 32b: second permanent magnet
6 a1, 6 b1: outer flux barrier
6 a2, 6 b2: inner flux barrier
100: Embedded type motor

Claims (20)

A stator having a plurality of teeth formed in a cylindrical inner peripheral portion of the yoke toward a center axis, the plurality of teeth being wound with coils; And
And a rotor rotatably installed inside the stator and having a plurality of magnetic poles composed of two permanent magnets formed at regular intervals in the circumferential direction,
The rotor may include:
An outer flux barrier made of a gap formed at each of the radially outer ends of the two permanent magnets,
Further comprising an inner flux barrier formed of air gaps formed at respective radially inner ends of the two permanent magnets,
And each of the inner flux barriers of the two permanent magnets is spatially connected to each other. The method according to claim 1,
Wherein the plurality of magnetic poles comprises:
And two permanent magnets arranged in a convex V-shape on the central axis. The method according to claim 1,
The rotor may include:
Further comprising a rotor iron core having a plurality of holes for inserting the two permanent magnets along an outer circumference thereof,
Wherein the two permanent magnets are made of a single-
Wherein the rotor core is disposed in a V-shape gradually apart from the rotation center of the rotor core toward the outside in the radial direction. The method of claim 3,
Further comprising a bridge portion formed along an outer peripheral surface of the rotor iron core,
The bridge unit includes:
Wherein the outer flux barrier is formed radially outward of the outer flux barrier. 5. The method of claim 4,
The magnetic flux density of the bridge portion varies depending on the width dimension of the bridge portion,
And the magnetic flux density of the bridge portion is set to 1.8 to 1.9T. 5. The method of claim 4,
(Where k is 1.65 to 1.75) when the inter-pole distance formed between the magnetic poles adjacent to each other is A and the width dimension of the teeth is B, respectively. The method according to claim 6,
The inter-
And the width of the magnetic flux passage formed between the outer flux barriers adjacent to each other in the adjacent magnetic poles. 5. The method of claim 4,
Wherein the outer flux barrier comprises:
A first space portion formed on the outer side in the radial direction outer end surface of the permanent magnet along the direction of the flat plate of the permanent magnet and a second space portion formed on the outer side of the V- Embedded motor. 9. The method of claim 8,
Wherein a circumferential dimension of an outer end of the outer flux barrier is at least five times the width dimension of the bridge portion. 3. The method of claim 2,
The opening angle of the permanent magnet arranged in the V shape is 120 DEG to 100 DEG,
Wherein a V-shaped vertex of the V-shaped permanent magnet is positioned on a center line of the teeth, and a tooth-line end face at a position closest to the radially outer end of the permanent magnet is located on the outer peripheral surface of the rotor And a magnet-embedded motor facing the inner portion of the permanent magnet disposed in the V-shape. The method according to claim 1,
And the slots formed between the teeth are positioned 1.5 to 3 relative to the magnetic poles adjacent to each other. The method according to claim 1,
And the radially inner ends of the two permanent magnets constituting the magnetic pole are in close contact with each other. A compressor having the magnet-embedded motor according to any one of claims 1 to 12. An air conditioner using the compressor having the magnet-embedded motor according to any one of claims 1 to 12. A refrigeration apparatus using the compressor having the magnet-embedded motor according to any one of claims 1 to 12. A shaft rotating about a central axis;
A stator having a plurality of teeth formed toward the central axis, the stator having coils wound around the teeth; And
And a rotor rotatably installed inside the stator and having a plurality of magnetic poles arranged in a convex V-shape at the central axis at regular intervals in the circumferential direction,
The rotor may include:
A rotor iron core having a plurality of magnet insertion holes formed along an outer periphery thereof,
A plurality of permanent magnets inserted into the plurality of magnet insertion holes to form the plurality of magnetic poles,
An outer flux barrier formed at each radially outer end of the plurality of permanent magnets,
Further comprising an inner flux barrier formed at each radially inner end of the plurality of permanent magnets,
Wherein the plurality of permanent magnets comprise:
Wherein the rotor core is disposed in a V-shape gradually apart from the rotation center of the rotor core toward the outside in the radial direction. 17. The method of claim 16,
Wherein the inner flux barriers of the plurality of permanent magnets are spatially connected to each other,
Wherein the outer flux barriers of the plurality of permanent magnets are formed in the radially inner side of the bridge portion formed along the outer peripheral surface of the rotor iron core. 18. The method of claim 17,
Wherein the outer flux barrier comprises:
A first space portion formed on the outer side in the radial direction outer end surface of the permanent magnet along the direction of the flat plate of the permanent magnet and a second space portion formed on the outer side of the V- Embedded motor. 17. The method of claim 16,
The opening angle of the permanent magnet arranged in the V shape is 120 DEG to 100 DEG,
Wherein a V-shaped vertex of the V-shaped permanent magnet is positioned on a center line of the teeth, and a tooth-line end face at a position closest to the radially outer end of the permanent magnet is located on the outer peripheral surface of the rotor And a magnet-embedded motor facing the inner portion of the permanent magnet disposed in the V-shape. A compressor having the magnet-embedded motor according to any one of claims 16 to 19.

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