JP5082825B2 - Rotor for embedded magnet type rotating electrical machine, embedded magnet type rotating electrical machine, vehicle, elevator, fluid machine, processing machine using the rotating electrical machine - Google Patents

Description

The present invention relates to a rotor for an embedded magnet type rotating electrical machine having a rotor capable of increasing the efficiency of the embedded magnet type rotating electrical machine, an embedded magnet type rotating electrical machine, a vehicle, an elevator, a fluid machine, and a processing machine using the rotating electrical machine. About.

2. Description of the Related Art Conventionally, for example, an embedded magnet type synchronous motor that has a rotor capable of improving the efficiency of an embedded magnet type rotating electrical machine and that is used as a power source for driving a fan or a pump is configured as follows.
In FIG. 4, 100 is a stator and 101 is a rotor.
The stator 100 is formed by punching electromagnetic steel sheets into slots and teeth and a stator yoke until a predetermined thickness is obtained after punching with a die, and at the same time, is fixed by caulking or the like to form a stator core. The core slot is formed by winding a winding serving as an electric loading means.
Further, the rotor 101 has an outer peripheral surface having a slightly smaller diameter than the inner peripheral surface of the stator 100 so as to secure a predetermined gap with the inner peripheral surface of the stator 100. After the magnet insertion holes for insertion are punched out with a mold, they are laminated until a predetermined thickness is reached, and at the same time, they are fixed by caulking or the like to constitute the rotor core 102.
Permanent magnets serving as magnetic loading means are inserted into the magnet insertion holes of the rotor core 102, and the permanent magnets are arranged in a first permanent magnet in which the permanent magnets are combined in a V shape for each pole of the rotor. 103 is embedded with the apex of the V shape facing the rotor shaft side, and a second permanent magnet 104 made of a flat permanent magnet is embedded in the outer peripheral portion of the rotor core 102 so as to substantially follow the outer periphery thereof. A pair of plate-like permanent magnets 103a and 103b constituting the first permanent magnet 103 are embedded symmetrically with respect to a radial line connecting the center of the rotor and the vertex of the V-shape, and the second permanent magnet 103 The magnet 104 is embedded and configured so that the magnet 104 is perpendicular to the radial line and the center position thereof is on the radial line (see, for example, Patent Document 1).
In the embedded magnet type synchronous motor, the direction of the magnetic flux generated by the permanent magnet is referred to as the d-axis, and the position shifted by 90 ° in electrical angle from the d-axis is referred to as the q-axis.
The magnetic path through which the magnetic flux caused by the current flowing through the stator winding passes through the rotor 101 includes a d-axis magnetic path that passes through the first and second permanent magnets 103 and 104, and the first permanent magnet. There is a magnetic path in the q-axis direction that passes between the magnet 103 and the second permanent magnet 104 and passes through the rotor core 102 in a direction perpendicular to the d-axis and the electrical angle.
Further, the magnetic flux generated by the permanent magnet is generated from the permanent magnet, flows from the teeth of the stator 100 opposed to each other through the gap through the rotor core 102 to the yoke, and to the permanent magnet at an electrical angle of 180 degrees. Constitutes a flowing magnetic path.
A reluctance torque is generated by causing a current to flow in the winding located on the d-axis of the stator and a current in a direction opposite to that flowing in the winding located on the d-axis to the winding located on the q-axis. For example, see Patent Document 2).
As described above, in the conventional embedded magnet type synchronous motor, the sum of the magnet torque and the reluctance torque becomes a rotational force, and a fan or a pump is driven through the shaft.
Japanese Patent No. 3605475 (7th page, FIG. 1) JP 2003-134706 (4th page, FIG. 1)

In conventional embedded magnet type synchronous motors, iron loss occurs due to the magnetic flux created by the permanent magnet embedded in each pole of the rotor, and the ratio of iron loss to total loss increases at low loads and high speeds. There was a problem of getting worse.
The present invention has been made in view of such problems. The magnetic flux flowing through the q-axis is reduced by the magnetic flux generated by the second permanent magnet, the iron loss is reduced, and the efficiency at the time of low load and high speed rotation is reduced. It is an object of the present invention to provide a rotor for an embedded magnet type rotating electrical machine, an embedded magnet type rotating electrical machine, and a vehicle, an elevator, a fluid machine, and a processing machine using the rotating electrical machine.

In order to achieve the above object, the present invention is configured as follows.
The invention of claim 1, wherein the embedded magnet type rotary electric machine rotor, a rotor core, a permanent magnet is embedded in said rotor core, a buried magnet type rotating electric machine rotor consisting of the The permanent magnet is composed of a first permanent magnet and a second permanent magnet, and the first permanent magnet is embedded in a V shape with the center of the rotor as the apex and the magnetization direction as the radial direction for each pole. In the rotor for an embedded magnet type rotating electrical machine , the second permanent magnet is embedded so that the magnetic flux is oriented in a direction orthogonal to the magnetic flux by the first permanent magnet at an electrical angle of 90 degrees. Are embedded symmetrically with respect to a radial line connecting the center of the rotor and the vertex of the V-shape, and the second permanent magnet is embedded along the radial line, and the second permanent magnet Is the outer side of the rotor in the radial direction than the first permanent magnet. By being embedded, the magnetic flux of the q-axis direction to make the current flowing through the armature coils, characterized by being arranged so as to cancel the magnetic flux by the second permanent magnet is made.
According to a second aspect of the invention, the embedded magnet type rotary electric machine rotor of claim 1, wherein said second permanent magnet, and wherein the higher coercivity than the first permanent magnet.
According to a third aspect of the present invention, in the rotor for an embedded magnet type rotating electric machine according to the first or second aspect , when the magnetization direction thickness of the first permanent magnet is t1,
The magnetization direction thickness t2 of the second permanent magnet is t2 ≦ 0.8 × t1.
It is characterized by becoming.
According to a fourth aspect of the present invention, in the rotor for an embedded magnet type rotating electric machine according to any one of the first to third aspects, the second permanent magnet is divided by a straight line connecting the center and the outer periphery of the rotor. It is characterized by comprising a plurality of magnet groups.
According to a fifth aspect of the present invention, there is provided a rotor for an embedded magnet type rotating electrical machine, and a rotor for the embedded magnet type rotating electrical machine supported in an internal space via a bearing, and a coil in its own slot. A rotor according to any one of claims 1 to 4 , wherein the rotor according to any one of claims 1 to 4 is used as the rotor for an embedded magnet type rotating electrical machine.
The invention according to claim 6 is the embedded magnet type rotating electrical machine according to claim 5 , wherein the embedded magnet type rotating electrical machine is for low load and high speed rotation.
The vehicle invention described in claim 7 is characterized in that the embedded magnet type rotating electrical machine described in claim 5 is used as a drive motor or a generator for driving the vehicle.
The elevator according to an eighth aspect is characterized in that the embedded magnet type rotating electrical machine according to the fifth aspect is used as a drive motor.
The invention of a fluid machine according to claim 9 is characterized in that the embedded magnet type rotating electrical machine according to claim 5 is used as a drive motor.
The invention of a processing machine according to claim 10 is characterized in that the embedded magnet type rotating electric machine according to claim 5 is used as a drive motor.

According to the first aspect of the present invention, the magnetic flux flowing in the q-axis direction at the time of low load and high speed rotation is reduced by the magnetic flux produced by the second permanent magnet. Loss can be reduced and efficiency can be improved.
According to the second aspect of the present invention, the first permanent magnet is embedded symmetrically with respect to the radial line connecting the center of the rotor and the vertex of the V shape, and the second permanent magnet is arranged along the radial line. By burying, the magnetic flux flowing in the q-axis direction at low load and high speed rotation is effectively reduced by the magnetic flux generated by the second permanent magnet, so that the magnetic saturation of the stator teeth part is alleviated, thus reducing iron loss. Can be reduced and the efficiency can be improved.
According to the invention of claim 3, since the amount of the first permanent magnet can be increased, the magnet torque can be increased.
According to the invention described in claim 4, by using a magnet having a high holding force as the second permanent magnet, the permanent demagnetization occurring in the second permanent magnet due to the magnetic flux generated by the armature winding at a high load can be reduced. can do.
Further, according to the invention of claim 5, since the influence on the magnetic path of the d-axis can be reduced, the decrease in magnet torque by the first permanent magnet by the second permanent magnet can be reduced, The output torque of the electric motor can be increased.
According to the sixth aspect of the present invention, since a magnetic path is formed between the divided permanent magnets, the influence on the magnetic path of the d axis can be reduced, so that the magnet torque can be increased.
According to the seventh aspect of the present invention, since the rotor according to any one of the first to sixth aspects is used as a rotor for an embedded magnet type rotating electrical machine, the embedded magnet type having the effect of the rotor described above is used. A rotating electrical machine is obtained.
According to the eighth aspect of the invention, a particularly great effect can be obtained by using it for low load and high speed rotation.
According to the invention described in claims 9 to 12, by using the embedded magnet type rotating electrical machine described in claim 7 as a drive motor or generator capable of rotating at high speed with low loss, a vehicle, an elevator, a fluid machine・ Improvement of energy consumption and efficiency in processing machines can be realized.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a front sectional view of an embedded magnet type synchronous motor according to a first embodiment of the present invention.
In FIG. 1, 1 is a rotor and 2 is a rotor core formed by laminating electromagnetic steel sheets. Reference numeral 3 denotes a V-shaped first permanent magnet embedded in the rotor core 2 for each pole, and reference numeral 4 denotes a second permanent magnet embedded in the rotor core 2 for each pole. Further, 11 is a stator, 12 is a stator core formed by laminating electromagnetic steel sheets, 13 is a tooth, and 14 is a yoke.
The first permanent magnet 3 is embedded with its V-shaped apex P facing the axial core side of the rotor core 2. The first permanent magnet 3 is embedded in line symmetry with respect to the radial line R connecting the center C of the rotor 1 and the V-shaped apex P, and the second permanent magnet 4 is placed on the radial line R. It is buried in.

The portion of the rotor of the first embodiment (FIG. 1) that is different from the rotor of the prior art (FIG. 4) is the second that allows the magnetic flux to flow in a direction orthogonal to the magnetic flux of the first permanent magnet by 90 degrees in electrical angle. This is a portion provided with the permanent magnet 4. That is, the magnetic flux generated by the first permanent magnet 3 is generated from the first permanent magnet 3 and flows in the d-axis direction (a in FIG. 1), and passes through the rotor core 2 and faces the stator G through the gap G. 11 (13) from the teeth 13 (b) to the yoke 12 (c.fwdarw.d), and (e) a magnetic path 15 is formed which flows to a permanent magnet at an electrical angle of 180 degrees.
Further, the magnetic flux generated by the second permanent magnet 4 flows in a direction (ie, q-axis direction) generated by the first permanent magnet 4 and shifted by 90 degrees in electrical angle from the magnetic flux generated by the first permanent magnet (see FIG. 1), a magnetic path 16 is formed by flowing through the rotor core 2 and through the opposing stator through a gap (b → c → d). Of the magnetic paths (a) to (e), a part of the permanent magnets adjacent to the permanent magnets in the magnetic paths (a) to (d) show the flow of magnetic flux generated by the magnets. Yes.
In the first embodiment (FIG. 1), the second permanent magnet 4 has its NS oriented in the radial direction, so that the second permanent magnet generates a magnetic flux in the q-axis direction especially at low load and high speed rotation. By canceling with the magnetic flux, the magnetic flux flowing through the magnetic path 16 can be reduced, the iron loss can be reduced, and the efficiency can be increased.

  At the time of rotation, a magnetic loss caused by the magnetic flux generated by the first permanent magnet 3 flows through the magnetic path 15. The ratio of iron loss to total loss is small at high load and low speed rotation, but the ratio of iron loss to total loss is very large at low load and high speed rotation, which is a major factor in reducing efficiency. 1 reduces the magnetic flux flowing in the magnetic path 16 by canceling out the q-axis magnetic flux generated by the current flowing through the armature coil at low load and high speed rotation by the magnetic flux generated by the second permanent magnet. Can reduce the efficiency.

FIG. 2 is a diagram showing the influence of the magnetization direction thickness of the second permanent magnet on the output torque of the electric motor with respect to the magnetization direction thickness of the first permanent magnet.
The horizontal axis represents the ratio (t2 / t1) of the magnetization direction thickness t1 of the first permanent magnet and the magnetization direction thickness t2 of the second permanent magnet, and the vertical axis represents the motor of the motor when t2 / t1 is 0.8. The output torque is shown when the output torque is 1.0.
When t2 / t1 becomes larger than 0.8, the output torque decreases. Therefore, in the present invention, t2 / t1 is set to 0.8.

FIG. 3 is a front sectional view of the embedded magnet type synchronous motor according to the second embodiment.
In FIG. 3, 5 is a second permanent magnet. The same constituent elements as those in the first embodiment (FIG. 1) are designated by the same reference numerals and the description thereof is omitted.
In Example 2, the 2nd permanent magnet 5 is a magnet group comprised from several permanent magnets 51, 52 ... 5n divided | segmented by the radial line of the rotor 1. FIG.
By dividing the permanent magnet 2 (FIG. 1) according to the first embodiment along the radial line of the rotor 1, a magnetic path is formed between the divided permanent magnet 51 and the permanent magnet 52, and the divided permanent magnet is divided. A magnetic path is formed between 52 and the permanent magnet 53 (hereinafter the same).
Compared to the magnetic path of the first embodiment, which is detoured along the outer periphery of the permanent magnet 2 of the first embodiment, in the second embodiment, a large number of magnetic paths can be formed between the divided permanent magnet and the adjacent permanent magnet. Since the influence of the permanent magnet 1 on the d-axis magnetic flux can be reduced, the maximum output torque of the electric motor can be increased.

  The embedded magnet type rotating electrical machine of the present invention can reduce iron loss during high-speed rotation by relaxing the magnetic flux saturation of the stator teeth portion by the second permanent magnet, so that the compressor and blower for wind and hydraulic power can be reduced. In addition to fluid machinery such as pumps, processing machines mainly for machine tool spindles that require high-speed rotation, drive motors and generators for hybrid vehicles, fuel cell vehicles, electric vehicles, etc., and drives for railway vehicles The present invention can also be applied to the use of motors for general industrial machinery such as motors and generators for generators, generators used for generator cars for uninterruptible power supplies, and elevators for elevators and multilevel parking lots.

1 is a front sectional view of an embedded magnet type synchronous motor according to Embodiment 1 of the present invention. It is the diagram which showed the influence which the magnetization direction thickness of the 2nd permanent magnet has on the output torque of an electric motor with respect to the magnetization direction thickness of the 1st permanent magnet which concerns on Example 1. FIG. FIG. 6 is a front sectional view of an embedded magnet type synchronous motor according to a second embodiment. It is a front sectional view of a conventional embedded magnet type synchronous motor.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Rotor core 3 1st permanent magnet 4 2nd permanent magnet which concerns on Example 1 5 2nd permanent magnet 11 which concerns on Example 2 Stator 12 Stator core 13 Teeth 14 Yoke 15 1st Magnetic path 16 formed by magnetic flux generated by permanent magnet 1 Magnetic path 100 formed by magnetic flux generated by second permanent magnet 2 Stator 101 Rotor 102 Rotor core 103 First permanent magnet 104 Second permanent magnet

Claims (10)

A rotor for an embedded magnet type rotating electrical machine comprising a rotor core and a permanent magnet embedded in the rotor core ,
The permanent magnet is composed of a first permanent magnet and a second permanent magnet, and the first permanent magnet is embedded in a V shape with the center of the rotor as the apex and the magnetization direction as the radial direction for each pole. And the second permanent magnet is embedded in a rotor for an embedded magnet type rotating electrical machine embedded so that the magnetic flux is oriented in a direction orthogonal to the magnetic flux by the first permanent magnet at an electrical angle of 90 degrees ,
The first permanent magnet is embedded in line symmetry with respect to a radial line connecting the center of the rotor and the vertex of the V-shaped, and the second permanent magnet is embedded along the radial line; and Since the second permanent magnet is embedded outside the first permanent magnet in the radial direction of the rotor, a magnetic flux in the q-axis direction generated by the current flowing through the armature coil is generated by the second permanent magnet. A rotor for an embedded magnet type rotating electrical machine, wherein the rotor is arranged so as to be canceled by a magnetic flux generated by a permanent magnet . The rotor for an embedded magnet type rotating electrical machine according to claim 1, wherein the second permanent magnet has a coercive force higher than that of the first permanent magnet . When the thickness in the magnetization direction of the first permanent magnet is t1,
The magnetization direction thickness t2 of the second permanent magnet is t2 ≦ 0.8 × t1.
The rotor for an embedded magnet type rotating electrical machine according to claim 1 or 2, wherein: The embedding according to any one of claims 1 to 3, wherein the second permanent magnet is composed of a plurality of magnet groups divided by a straight line connecting the center and the outer periphery of the rotor. Magnet type rotor for electric rotating machine. An embedded magnet type rotating machine comprising: an embedded magnet type rotating electrical machine rotor; and a stator in which the embedded magnet type rotating electrical machine rotor is supported in an internal space through a bearing and a coil is wound in its own slot. In electric
An embedded magnet type rotating electrical machine using the rotor according to claim 1 as the rotor for an embedded magnet type rotating electrical machine . 6. The embedded magnet type rotating electrical machine according to claim 5, wherein the embedded magnet type rotating electrical machine is for low load and high speed rotation . 6. A vehicle using the embedded magnet type rotating electric machine according to claim 5 as a drive motor or a generator for driving the vehicle . An elevator using the embedded magnet type rotating electric machine according to claim 5 as a drive motor . 6. A fluid machine using the embedded magnet type rotating electric machine according to claim 5 as a drive motor . 6. A processing machine using the embedded magnet type rotating electric machine according to claim 5 as a drive motor.

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