JP2001251825A - Permanent magnet synchronous motor and air conditioner using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve efficiency of an electric motor and operating efficiency of an air conditioner, by optimizing a stator applying concentrated windings to teeth of a permanent magnet synchronous motor and a magnet or its shape based on the relation to generation loss. SOLUTION: This synchronous motor is provided with a stator 2, applying a concentrated winding to a plurality of teeth 6 of a stator core 4 and a rotor 3 having a rare earth magnet 10 of shape opening a sectional shape vertical to a rotary shaft spread to the outward per pole in the inside of a rotor core 8, a magnet axial center opening θ1 from the rotational axial center P in the external diametric innermost side of the rare earth magnet 10 is constituted by an electrical angle in the range of 111 to 119 degrees, also a width W1 of a slot opening part formed between the teeth is constituted in the dimensional range of 2.4 to 3.4 mm.

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 synchronous motor and an air conditioner using the same, and more particularly to an air conditioner,
The present invention is suitable for a permanent magnet synchronous motor for driving a compressor and an air conditioner using the same, which is mounted on a device such as a refrigerator such as a heating / cooling / freezing / refrigeration unit.

[0002]

2. Description of the Related Art Conventional brushless DC motors include:
As shown in JP-A-9-298852,
In a brushless DC motor composed of a stator and a rotor disposed inside the air gap via an air gap, a sufficient torque is generated by obtaining a sufficient stator magnetic flux to improve the motor efficiency. 3 on iron core
A phase coil is wound to form a stator, and a field is formed by a magnet embedded inside a rotor core such that a cross-sectional shape perpendicular to the rotation axis 4 is substantially V-shaped or substantially U-shaped at each pole. In addition, the magnets constituting the respective poles are configured such that the opening angle from the V-shaped or U-shaped rotation axis of the magnet is 120 ° or more in electrical angle, and the rotor is configured to conduct three-phase sensorless energization to the stator coil. is there.

[0003]

However, such a conventional brushless DC motor does not refer to the form of the stator, and the stator with concentrated teeth wound on the teeth and the magnet or the shape of the magnet causes loss of generation. No mention was made of optimizing the relationship in order to improve the motor efficiency.

SUMMARY OF THE INVENTION An object of the present invention is to provide a permanent magnet type synchronous motor which optimizes a stator in which teeth are concentratedly wound and a magnet or a shape of the magnet in relation to a generated loss to improve the motor efficiency, and a synchronous motor using the same. An object of the present invention is to provide an air conditioner capable of improving operation efficiency.

[0005]

A first feature of the present invention to achieve the above object is to provide a stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rotating shaft provided inside the rotor core. And a rotor having a rare earth magnet whose cross section perpendicular to the outer periphery is expanded outward per pole. The magnet shaft opening from the rotation shaft center on the outermost diameter inside of the rare earth magnet is represented by an electrical angle. 11
The present invention is configured so that the width of the slot opening formed between the teeth of the stator core is 2.4 mm to 3.4 mm.

A second feature of the present invention is that the degree of opening of the magnet axis from the innermost rotation axis of the rare-earth magnet is 1 electrical angle.
The present invention is characterized in that the width is 11 to 115 degrees and the width of the slot opening formed between the plurality of teeth of the stator core is 1.4 mm to 3.4 mm or less.

[0007] A third feature of the present invention is that the ratio of the width of the slot opening formed between the plurality of teeth of the stator core to the opening of the magnet axis of the rare earth magnet is 0.0201 to 0. 0306.

A fourth feature of the present invention is that the degree of opening of the magnet shaft center from the rotation shaft inside the outermost diameter of the rare earth magnet is 1 electrical angle.
In addition to the angle between 11 degrees and 119 degrees, a plurality of magnet slots for accommodating the rare earth magnet are provided for each rare earth magnet, and the minimum width between a pair of the magnet slots on the rotating shaft side is set to 0.1 mm. That is, it is configured from 5 mm to 1.0 mm.

A fifth feature of the present invention is that the degree of opening of the magnet shaft center from the rotation shaft inside the outermost diameter of the rare earth magnet is 1 electrical angle.
A plurality of magnet slots for accommodating the rare-earth magnet are provided for each rare-earth magnet, and a space is provided in an iron core between the pair of the rotating shaft-side magnet slots of the magnet slots. Has been established.

A sixth feature of the present invention is that a refrigeration cycle in which a compressor, an indoor heat exchanger, an expansion valve and an outdoor heat exchanger are sequentially connected, and an indoor blower for promoting heat exchange of the indoor heat exchanger And a motor for an outdoor blower that promotes heat exchange of the outdoor heat exchanger. A permanent magnet synchronous motor is used as a motor for driving the compressor, and the permanent magnet synchronous motor includes a stator core. A stator having concentrated teeth wound on a plurality of teeth, and a rotor having a rare earth magnet having a shape in which a cross-sectional shape perpendicular to the rotation axis expands outward per pole inside a rotor core, An opening angle of the magnet axis from the outermost inner rotation axis of the rare earth magnet is set to 111 to 119 degrees in electrical angle, and a slot opening formed between the plurality of teeth of the stator core. 2.
The configuration is from 4 mm to 3.4 mm.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. FIG. 1 is a radial sectional view of a permanent magnet type synchronous motor according to a first embodiment of the present invention. In the second and subsequent embodiments, the description overlapping with the first embodiment will be omitted. The same reference numerals in the drawings of the respective embodiments indicate the same or corresponding components.

In FIG. 1, a permanent magnet type synchronous motor 1 is shown.
Is composed of a stator 2 and a rotor 3. The stator 2 includes a stator core 4 and a concentrated winding stator winding 5,
The stator winding 5 is wound around the teeth 6 in slots 7 between the teeth 6. The rotor 3 includes a rotor core 8 and magnet slots 9 formed in the rotor core 8.
And a rare earth magnet 10 inserted and arranged in a magnet slot 9.
And a shaft 11, and the rotor axis is represented by P. The width W1 is between the teeth 6 of the stator 2.
Are provided, and are represented by 4 poles and 6 slots. The rare-earth magnets 10 arranged on the rotor 3 have a substantially V-shape that expands outwardly from the four poles, and are housed in the respective magnet slots 9. There is an inter-slot iron core 13 between each magnet slot 9, and the minimum width is W2. A line between the rotor outer peripheral corner of the magnet slot 9 for one pole and the rotor axis P is referred to as a magnet axis center opening, and the magnet axis center opening is defined as θ1 and one pole. The distance between the lines connecting the outer peripheral side of the rotor of the minute magnet slot 9 is called a magnet opening, and the magnet opening is θ2.

The characteristics of the permanent magnet type synchronous motor are as follows. The motor output is measured using a wattmeter via a torque meter and a load device, and the motor output is measured from the torque meter value when the motor output is absorbed by the load device. it can. The result of subtracting the motor output from the motor output is the generated loss. When the generated loss is separated, unknown loss is extracted in addition to ordinary copper loss, iron loss, and mechanical loss. This unknown loss is commonly referred to as stray loss. However, experiments have shown that the value of the stray loss is as large as the copper loss. Therefore, reducing the stray loss is important for improving the motor efficiency.

Therefore, in the present invention, the opening angle from the rotation axis of the rare earth magnet 10 expanding outward in a substantially V-shape or substantially U-shape per magnetic pole, that is, the magnet axis opening degree θ1 and The generated loss was separated using the width W1 of the opening of the slot 7 formed between the plurality of teeth of the stator core as a parameter, and the stray loss was extracted.

FIG. 2 is a diagram showing the relationship between the magnet shaft center opening and the stray loss of the permanent magnet type synchronous motor of FIG. The vertical axis in FIG. 2 indicates that the slot opening width W1 is 2.4 mm when the magnet axis opening θ1 is the minimum 107 degrees, and the slot opening width W1 is 123 degrees when the magnet axis opening θ1 is the maximum 123 degrees. Is 3.4 mm, the stray loss is the minimum value, and the measured values of the stray loss when the magnet shaft center opening θ1 and the width W1 of the slot opening are used as parameters are taken as reference values. It is shown in terms of the ratio with respect to.

As apparent from FIG. 2, it is understood that the stray loss ratio has a minimum value with respect to the width W1 of the slot opening portion for each magnet shaft center opening degree θ1. In FIG. 2, the minimum value of each stray loss ratio is the width W1 of the slot opening.
Exists in the range of 2.4 mm to 3.4 mm, but all of these minimum values are less than the minimum reference value when the magnet shaft center opening θ1 is in the range of 111 degrees to 119 degrees. That is, in order to obtain an electric motor having a stray loss ratio less than the reference value, the width W1 of the slot opening needs to be set in the range of 2.4 mm to 3.4 mm and the magnet shaft opening θ1 must be set in the range of 111 ° to 119 °. There is. As is clear from FIG. 2, the ratio between the width W1 of the slot opening and the magnet axis opening θ1 of the magnet is determined within the above range from the width W1 of the slot opening and the magnet axis opening θ1.
Can be selected, the minimum value 2.4 / 119 = 0.0201 to the maximum value 3.4 / 11
It can be confirmed that it is necessary to set the range of 1 = 0.0306.

Further, the opening angle θ1 of the magnet shaft center is changed from 111 degrees to 1 degree.
In the range of 15 degrees, the width W1 of the slot opening is 1.4 m.
In the range from m to 3.4 mm, it can be confirmed that the stray loss is smaller than the reference characteristic lines when the magnet shaft center opening θ1 is 107 degrees and 123 degrees.

Further, when the magnet shaft center opening θ1 is in the range of 111 ° to 115 °, the width W1 of the slot opening is 2.
It can be confirmed that the stray loss is smaller than the minimum reference value in the range of 0 mm to 3.4 mm.

Further, the opening angle θ1 of the magnet shaft center is changed from 115 degrees to 1 degree.
In the range of 19 degrees, the width W1 of the slot opening is 2.4 m.
It can be confirmed that the stray loss is smaller than the minimum reference value in the range from m to 3.5 mm.

Further, since the magnet slots 9 are provided for each of the rare earth magnets 10, the rare earth magnets 10 are provided.
Can be fixed, and variations in performance as an electric motor can be minimized.

The minimum width W of the core 13 between the slots shown in FIG.
2 is determined from the shape of the magnet required from the motor performance and the strength of the electromagnetic steel plate, and is configured in the range of 0.5 mm to 1.0 mm, so that the amount of leakage magnetic flux can be reduced, and the magnetic flux of the magnet is reduced. Effective use can improve the motor efficiency.

In addition to the above embodiment, although not shown, there is a similar relationship between the magnet opening θ2 and the stray loss with respect to the magnet opening θ2. According to this, it has been confirmed that the optimum width W1 of the slot opening and the magnet opening θ2 are the same as the results of the magnet shaft center opening θ1 described above. However, there is a state where it is impossible to make the magnet axis center opening θ1 and the magnet opening θ2 completely coincide with each other.
It can be handled by keeping the deviation of 2 within ± 2 degrees.

Next, a second embodiment of the present invention will be described with reference to FIG. FIG. 3 is a radial sectional view of a permanent magnet type synchronous motor according to a second embodiment of the present invention.

The second embodiment is different from the first embodiment in that an inter-slot core 1 is provided between each magnet slot 9.
3 in that a space 14 is provided in the iron core 13 between the magnet slots. Space 1 in core 13 between magnet slots
4 to increase the magnetic reluctance of the inter-slot core 13, the amount of leakage magnetic flux in the inter-slot core can be reduced as compared with the rotor of the first embodiment, and the magnetic flux of the magnet is effectively used. It is possible to further improve the motor efficiency.

Next, a third embodiment of the present invention will be described with reference to FIG. FIG. 4 is a radial sectional view of a permanent magnet type synchronous motor according to a third embodiment of the present invention.

The third embodiment is different from the first embodiment in that the rare-earth magnet 10 is formed into a substantially U-shape which is convex toward the center of the four-pole rotor, and is housed in the respective magnet slots 9. The same operation and effect as the rotor shown in the first embodiment can be obtained, and the number of rare earth magnets to be used is 8
Since the cost can be reduced by reducing the number of sheets to four, the cost of the electric motor can be reduced.

In each of the embodiments described above, a motor having a four-pole structure has been described. However, it goes without saying that the present invention can effectively contribute to a motor having any number of poles such as two poles and six poles.

Next, a fourth embodiment of the present invention will be described with reference to FIG. FIG. 5 is a refrigeration cycle system diagram of an air conditioner according to a fourth embodiment of the present invention.

This air conditioner forms a refrigeration cycle in which a compressor 21, an indoor heat exchanger 22, an indoor expansion valve 24, an outdoor heat exchanger 25, and an accumulator 27 are sequentially connected. And an outdoor blower motor 26 that promotes heat exchange between the outdoor unit 29 and the outdoor fan 29. Further, an outside air thermistor 28 for detecting the outside air temperature is provided. The compressor 21 uses any one of the permanent magnet synchronous motors of the above-described embodiments as a motor to be driven.

According to the air conditioner, the operation efficiency can be improved by using any of the permanent magnet type synchronous motors of the above-described embodiments, and particularly, the operation efficiency at low speed operation is remarkably improved. can do.

[0031]

According to the present invention, a permanent magnet type synchronous motor which can improve the motor efficiency by optimizing the stator in which the teeth are concentratedly wound and the shape of the magnet or the magnet in relation to the generated loss and the operation efficiency It is possible to provide an air conditioner that can improve the air conditioner.

[Brief description of the drawings]

FIG. 1 is a radial sectional view of a permanent magnet type synchronous motor according to a first embodiment of the present invention.

FIG. 2 is a characteristic diagram showing a relationship between a magnet shaft center opening and stray loss of the permanent magnet type synchronous motor of FIG.

FIG. 3 is a radial sectional view of a permanent magnet type synchronous motor according to a second embodiment of the present invention.

FIG. 4 is a radial sectional view of a permanent magnet type synchronous motor according to a third embodiment of the present invention.

FIG. 5 is a refrigeration cycle system diagram of an air conditioner according to a fourth embodiment of the present invention.

[Explanation of symbols]

1: permanent magnet synchronous motor, 2: stator, 3: rotor,
4 ... stator core, 5 ... stator winding, 6 ... teeth, 7 ...
Slot, 8 ... rotor core, 9 ... magnet slot, 10 ...
Rare earth magnet, 11 ... shaft, 12 ... slot opening,
13: iron core between slots, 14: space, 21: compressor,
22 indoor heat exchanger 23 electric motor for indoor blower 24
... indoor expansion valve, 25 ... outdoor heat exchanger, 26 ... electric motor for outdoor blower, 27 ... accumulator, 29 ... outdoor unit, 3
0: Indoor unit.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat ゛ (Reference) H02K 1/27 501 H02K 1/27 501M 501K 19/10 19/10 A (72) Inventor Manabu Sasaki Ibaraki 7-1-1, Omikacho, Hitachi City Hitachi Research Laboratory, Hitachi, Ltd. (72) Inventor Mika Takahashi 7-1-1, Omikamachi, Hitachi City, Ibaraki Prefecture Hitachi Research Laboratory, Hitachi, Ltd. (72) Invention Person Keiji Noma 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Prefecture, Hitachi, Ltd.Industrial Equipment Group (72) Inventor Kazuo Sato 7-1-1, Higashi-Narashino, Narashino-shi, Chiba Prefecture, Japan Industrial Equipment Group (72 Inventor Shoji Senoo 7-1-1 Higashi Narashino, Narashino City, Chiba Prefecture Industrial Machinery Group, Hitachi, Ltd. Over-flops in the F-term (reference) 3L050 BA04 5H002 AA02 AD04 AE06 5H619 AA01 BB01 BB06 BB22 BB24 PP01 PP02 PP04 PP05 PP08 PP14 5H621 GA01 GA04 GA16 5H622 AA03 CA02 CA13 CB03 DD02

Claims (6)

[Claims] 1. A stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rare-earth magnet having a cross section perpendicular to a rotation axis and expanding outward per pole inside a rotor core. And an opening angle of the magnet axis from the rotation axis inside the outermost diameter of the rare-earth magnet of 111 degrees to 1 degree in electrical angle.
The width of the slot opening formed between the plurality of teeth of the stator core is 2.4 m.
3. A permanent magnet type synchronous motor characterized in that the length is from 3.4 m to 3.4 mm. 2. A stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rare-earth magnet having a cross section perpendicular to the rotation axis, which is expanded outward per pole, is provided inside the rotor core. And an opening angle of the magnet axis from the rotation axis inside the outermost diameter of the rare-earth magnet of 111 degrees to 1 degree in electrical angle.
15 degree, and the width of the slot opening formed between the plurality of teeth of the stator core is 1.4 m.
A permanent magnet type synchronous motor characterized in that it is configured to be 3.4 mm or less from m. 3. A stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rare-earth magnet having a cross section perpendicular to the rotation axis and expanding outward per pole inside the rotor core. And a ratio of a width of a slot opening formed between the plurality of teeth of the stator core and a degree of opening of a magnet axis of the rare-earth magnet to 0.0201 to 0.030.
6. A permanent magnet type synchronous motor, wherein the motor is configured as described above. 4. A stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rare-earth magnet having a cross section perpendicular to the rotation axis and expanding outward per pole is provided inside the rotor core. And an opening angle of the magnet axis from the rotation axis inside the outermost diameter of the rare-earth magnet of 111 degrees to 1 degree in electrical angle.
A plurality of magnet slots for accommodating the rare earth magnet are provided for each rare earth magnet, and the minimum width between a pair of the magnet slots on the rotation axis side of the magnet slot is 0.5 mm to 1 mm. A permanent magnet type synchronous motor characterized by having a length of 0.0 mm. 5. A stator in which a plurality of teeth of a stator core are wound in a concentrated manner, and a rare-earth magnet having a cross section perpendicular to the rotation axis and expanding outward per pole inside the rotor core. And an opening angle of the magnet axis from the rotation axis inside the outermost diameter of the rare-earth magnet of 111 degrees to 1 degree in electrical angle.
A plurality of magnet slots for accommodating the rare earth magnets are provided for each rare earth magnet, and a space is provided in an iron core between a pair of the magnet slots on the rotating shaft side of the magnet slots. A permanent magnet type synchronous motor characterized by the above-mentioned. 6. A refrigeration cycle in which a compressor, an indoor heat exchanger, an expansion valve, and an outdoor heat exchanger are sequentially connected, an indoor blower motor for promoting heat exchange of the indoor heat exchanger, and the outdoor heat An electric motor for an outdoor blower that promotes heat exchange of the exchanger; and a permanent magnet synchronous motor is used as a motor for driving the compressor. The permanent magnet synchronous motor is concentratedly wound around a plurality of teeth of a stator core. And a stator with
A rotor having a rare earth magnet whose cross section perpendicular to the rotation axis is expanded outward per pole inside the rotor core; and The opening angle of the magnet shaft is set to 111 to 119 degrees in electrical angle, and the width of the slot opening formed between the plurality of teeth of the stator core is set to 2.4 mm to 3.4 mm.
An air conditioner characterized by comprising: