JPH07107719A - Permanent magnet electric rotating machine - Google Patents

Abstract

PURPOSE:To provide a permanent magnet electric rotary machine, in which the lowering of the quantity of diametral magnetic flux interlinked with a stator is inhibited even when there is a rataining ring and cogging torque and electromagnetic loss are reduced. CONSTITUTION:A retaining ring 7 fixing a permanent magnet 6 is formed of a magnetic material having low saturation magnetic flux density, relative permeability is brought to 100 or more in magnetic flux density of 0.5-0.8(T) and to 100 or less in magnetic flux density of 1.6(T) at that time, a new permanent magnet is arranged to the interpole section of the permanent magnet 6 in the orthogonal magnetizing direction, a magnetic wedge fitted into a slot is manufactured of a silicon steel plate, an amorphous material or a material of specific permeability of 100 or more in magnetic flux density of 0.5-0.8(T) or a material of relative permeability of 100 or less in magnetic flux density of 1.6(T) or more, and a cylindrical body covering the slot from the inside is also prepared of the same material.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a permanent magnet type rotating electric machine that operates in an ultra-high speed rotation or a high temperature environment, and further relates to a permanent magnet type rotating electric machine in which the adverse effect of the iron core slot of the stator is corrected.

[0002]

2. Description of the Related Art A rotary electric machine is operated at a very high speed, for example, 2000.
When operating at a high speed of 0 rpm or more, in an induction machine or a general rotating field synchronous machine, the centrifugal force of the rotor is considerably large, and the rotor coil cannot withstand this centrifugal force. However, there is a problem that the rotor is distorted or stretches in the axial direction and cannot withstand high speed rotation.

However, in a rotary electric machine using a permanent magnet as a field of the rotor, heat is not generated because there is no coil in the rotor, and ultra-high speed rotation is relatively easy. The force acts on the permanent magnets, and the adhesive for fixing the permanent magnets to the rotor core may not be able to withstand the tensile strength of this centrifugal force and may scatter, so that the permanent magnet fixing means is provided from the outside.

As an example of the construction of a permanent magnet type rotary electric machine, as shown in FIG. 20, a stator 1 having a stator core 2 and a coil 3, a rotor core 5 around a shaft and a permanent magnet 6 on the outer periphery of the surface thereof are provided. It has a rotor 4. Then, in order to prevent the permanent magnets 6 from scattering due to the centrifugal force, the holding ring 7 made of a non-magnetic material for fixing the permanent magnets 6 from the outside.
Is provided.

In this case, when a magnetic material such as S45C used for the yoke is used as the holding ring 7, the holding ring 7
A closed magnetic circuit is formed by the permanent magnet 6 and the rotor core 5, and most of the field magnetic flux does not interlink with the stator coil 3 and the output of the rotating electric machine is very small. Therefore, the holding ring 7 is made of a non-magnetic steel material such as SUS304 or Inconel and has a considerable thickness, and is further formed by winding a tungsten wire, a wire material such as Kepra fiber, or an epoxy glass tape. Can be done.

In addition, a permanent magnet type rotary electric machine is provided with, for example, 200
When used in a high temperature environment of ℃ or higher, the adhesive for fixing the permanent magnets 6 to the rotor core 5 deteriorates due to heat and loses its adhesive strength. The means for fixing the permanent magnet 6 by providing the retaining ring 7 is adopted.

Next, considering slots in the stator iron core of the permanent magnet type rotating electric machine, as shown in FIG. 21, a coil 3 is arranged on the inner circumference of the stator iron core 2 of the permanent magnet type rotating electric machine. There is a slot 3a.
The opening facing the void surface of the iron core of the slot 3a is an opening slot in the case of a large capacity machine and a semi-closed slot in the case of a small capacity machine, but the opening contains, for example, a ferrite material or an iron component. Magnetic wedge 3 made of epoxy resin
b is arranged. The magnetic wedge 3b is provided for alleviating the influence of the slot 3a on the rotary electric machine characteristics.

[0008]

However, in the permanent magnet type rotary electric machine, the existence of the non-magnetic material retaining ring 7 for coping with the ultra-high speed rotation is caused by the gap between the stator 1 and the rotor 4. The length is increased, the magnetomotive force is greatly reduced between the air gaps, and the air gap magnetic flux density is reduced, resulting in a reduction in output as a rotating electric machine.

The same phenomenon occurs due to the presence of the retaining ring made of a non-magnetic material which accompanies thermal deterioration in a high temperature environment. Further, since the stator iron core 2 of the permanent magnet type rotating electric machine has the slot 3a, the air gap permeance changes depending on whether the center of the permanent magnet 6 is located at a position facing the tooth 2a or at the position facing the slot 3a. To do. For this reason, a cogging torque for holding the rotor 4 is generated even when it is not excited, and this cogging torque causes pulsation of the driving torque and the rotation speed of the motor output shaft. In particular, in rotating electrical machines with open slots,
The cogging torque becomes very large. Further, when the magnet surface is viewed locally, the operating point of the permanent magnet 6 and the air gap magnetic flux density change greatly depending on the positions of the slots 3a and the teeth 2a, so that an eddy current is generated in the permanent magnet 6, hysteresis loss, etc. Electromagnetic loss occurs.

In view of the above problems, the present invention does not reduce the amount of magnetic flux of the field interlinking with the stator and does not increase the volume of the rotating electric machine even if there is a retaining ring for ultra-high speed rotation. An object of the present invention is to provide a permanent magnet type rotating electric machine capable of firmly fixing a permanent magnet to a rotor core.

It is another object of the present invention to provide a permanent magnet type rotating electric machine having excellent characteristics by suppressing cogging torque and electromagnetic loss due to the existence of slots by the stator.

[0012]

In order to achieve the above object, the present invention has a stator in which a coil is wound around an iron core of a magnetic material to form an armature, and the iron core of the magnetic material is arranged in the circumferential direction of the surface. The gist of the present invention is to have a rotor in which a permanent magnet is covered and fixed by a retaining ring made of a magnetic material having a low saturation magnetic flux density.

According to the present invention, the retaining ring has a magnetic flux density of 0.5 to 0.8 (T), a relative magnetic permeability of 100 or more, and a magnetic flux density of 1.6 (T) or more. Relative permeability is 1
The gist is that the magnetic material is made of a magnetic material having a magnetic property of 00 or less.

Further, according to the present invention, a new permanent magnet is further arranged in a gap between the permanent magnets arranged in the circumferential direction of the surface of the iron core of the magnetic material, and the magnetization direction of the new permanent magnet is changed to the gap between the poles. The gist is that they are arranged so as to be orthogonal to the magnetizing direction of the permanent magnet and the magnet forming the part.

Further, according to the present invention, in a permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed therein, and a rotor having a permanent magnet arranged on the surface of the iron core, the rotary electric machine of the present invention is provided with a slot. The gist is that a magnetic wedge made of a plain steel plate is arranged.

Further, according to the present invention, in a permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed therein, and a rotor having a permanent magnet arranged on the surface of the iron core, an amorphous portion is provided at an opening of the slot. The gist is that a magnetic wedge made of a magnetic material is arranged.

Further, according to the present invention, in a permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed therein, and a rotor having permanent magnets arranged on the surface of the iron core, an opening portion of the slot is provided. The magnetic flux density is 0.5 to 0.
A magnetic wedge made of a soft magnetic material having a magnetic characteristic of 8 (T) and a relative magnetic permeability of 100 or more, a magnetic flux density of 1.6 (T) or more and a relative magnetic permeability of 100 or less is arranged. To do.

Further, the present invention provides a permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed on the inner periphery thereof, and a rotor having permanent magnets arranged on the surface of the iron core. The gist is that a cylindrical body of a silicon steel plate is arranged facing the rotor on the inner peripheral side.

Further, the present invention provides a permanent magnet type rotating electrical machine having a stator having an iron core having slots and teeth formed on the inner periphery thereof, and a rotor having permanent magnets arranged on the surface of the iron core. The gist of the present invention is to dispose a cylindrical body of spirally wound amorphous magnetic material facing the rotor on the inner peripheral side.

Further, the present invention provides a permanent magnet type rotating electrical machine having a stator having an iron core having slots and teeth formed on the inner circumference thereof, and a rotor having permanent magnets arranged on the surface of the iron core. The magnetic flux density is 0.5 to 0.8 (T) and the relative magnetic permeability is 100 or more, and the magnetic flux density is 1.6 or more and the relative magnetic permeability is 100 or less. The gist is that a cylindrical body of a soft magnetic material having a certain magnetic characteristic is arranged.

[0021]

The holding ring is made by processing a metal plate itself into a ring shape. For example, if the holding ring has a weight of about 30 kgf / mm ² or more, sufficient strength can be obtained. Therefore, it can sufficiently withstand the centrifugal force of the permanent magnet generated during rotation, the permanent magnet is firmly fixed to the surface of the rotor core, and the permanent magnet is used to hold the permanent magnet by the retaining ring even in a high temperature environment where an adhesive cannot be used. It can be mechanically fixed to the iron core.

Since the magnetic flux density of the air gap by the permanent magnet without the retaining ring is designed to be 0.8 (T), the relative permeability of the retaining ring is compared in the vicinity of this magnetic flux density. By making it with a magnetic material that is relatively high, magnetic gaps are not created in the radial direction of the magnetic poles, while magnetic flux in the circumferential direction leaks due to the retaining ring of the magnetic material in the circumferential magnetic field, but there is a gap between the permanent magnets. As the magnetic flux leaks from the magnet surface through the retaining ring as it approaches, the amount of magnetic flux increases near the circumferential end of the permanent magnet.
For example, by lowering the relative permeability at 1.6 (T), the magnetic resistance in the inter-electrode portion is increased, and the magnetic flux leakage in the circumferential direction is saturated by a small amount.

Therefore, the relative magnetic permeability is high in the radial magnetic flux density, and the relative magnetic permeability is low in the high magnetic flux density at the magnetic pole end.
By forming the retaining ring with a magnetic material having a low so-called saturation magnetic flux density, the number of magnetic fluxes interlinking with the stator is not extremely reduced, and it is not necessary to increase the volume of the rotating electric machine.

In addition, when a new permanent magnet is further arranged in the gap between the permanent magnets, since the magnetic flux of the new permanent magnet is directed to the end of the original permanent magnet, the original field The leakage flux of the permanent magnet is in the opposite direction to the flux of the inter-pole magnet. As a result, the magnetic flux of the original permanent magnet that is about to leak is repelled by the inter-pole magnet, and the amount of effective magnetic flux that passes through the air gap and links with the stator further increases.

Further, the slots and teeth are alternately formed in the stator core, and the permeance of the air gap changes, and the air gap magnetic flux concentrates on the portion facing the teeth, and the magnetic flux density distribution sharply changes between the teeth and the slots. Although changing, the magnetic flux passing through the teeth is distributed smoothly by the retaining ring of the magnetic material on the surface of the permanent magnet, which reduces the rate of change in magnetic energy and reduces the cogging torque.

Further, considering a magnetic circuit composed of a retaining ring magnetically connected to the permanent magnet, a gap, a stator core, and a rotor core, using a permanent magnet, which is a field magnet, as a magnetomotive force source, the thickness in the radial direction is considered. Therefore, since the retaining ring continuous in the circumferential direction is arranged in series with the permanent magnet, the permeance of the external magnetic circuit viewed from the permanent magnet is constant regardless of the rotational position. Thus, the cogging torque is small. Also,
In the magnetic circuit state of the rotating electric machine, the operating point on the magnetic characteristic curve (magnetic flux density-magnetizing force characteristic) of the permanent magnet is substantially constant, and the magnetic loss of the permanent magnet is small.

Further, in the present invention, by disposing a magnetic wedge having a relatively high magnetic permeability in the slot opening, the magnetic resistance along the circumferential direction of the air gap becomes relatively uniform, and a partial drop in the air gap magnetic flux density distribution occurs. Small and smooth.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment according to the present invention will now be described with reference to FIGS.
Will be described with reference to. A description will be given of a holding ring as a first embodiment. 1 is a sectional view taken along the axis of an embodiment of a permanent magnet type rotating electric machine, and FIG. 2 is a sectional view taken along the line AA of FIG. In FIGS. 1 and 2, 1 is a stator in which silicon steel plates are laminated, 2 is a stator iron core, and teeth 2a and slots 3a of the stator iron core 2 are alternately formed on the inner peripheral side thereof, and inside this slot 3a The coil 3 is inserted in.

On the other hand, the rotor core 5 forming the rotor 4 is made of a magnetic material of S45C, and a radially magnetized permanent magnet 6 is arranged on the outer peripheral surface of the rotor core 5. In this example, two magnets 6 forming two poles are arranged. A retaining ring 7 made of a magnetic material is arranged on the outer peripheral surface of the permanent magnet 6. The material of the retaining ring 7 is such that the magnetic flux density is 0.5 to 0.8 (T) and the relative magnetic permeability is 100 or more, and the magnetic flux density is 1.6 (T) or more and the relative magnetic permeability is close to 10. SUS630 is used.

The material of SUS630, which is the retaining ring 7, has a proof stress of about 100 kgf / mm ² , has a very high strength, and can sufficiently withstand the centrifugal force generated during rotation. It is firmly fixed to.

FIG. 3 shows the magnetic characteristics of the retaining ring applied to an example of the permanent magnet type rotary electric machine according to the present embodiment, and shows the tendency of increase in the magnetic flux density with respect to the magnetizing force. Further, FIG. 4 shows the relationship between the relative magnetic permeability and the magnetic flux density of the retaining ring. In FIG. 4, S45C and SUS630 are compared, and when the magnetic flux density of the air gap generated by the permanent magnet 6 when the retaining ring 7 is not present is 0.8 (T) in terms of magnetic design, the magnetic flux density is 0.8%. The relative magnetic permeability of SUS630 in (T) is about 120. Therefore, the retaining ring 7 does not form a magnetic gap in the radial direction of the magnetic pole portion, and the decrease in magnetic flux density is slight.

On the other hand, in the circumferential magnetic field, since the retaining ring 7 is a magnetic material, magnetic flux leaks in the circumferential direction along the retaining ring 7, but the magnetic flux leaks from the magnet surface through the retaining ring 7 as it approaches the inter-pole portion. , The magnetic flux density increases, and the magnetic flux density is 1.6 in the retaining ring 7 near the end of the magnet 6 in the circumferential direction.
(T) or more, and 2 (T) or more near the gap. However, as shown in FIG. 4, in the retaining ring 7 of this embodiment, the relative magnetic permeability of 1.6 (T) or more is close to 10, and the magnetic resistance in the gap between the poles is considerably large, and the magnetic flux in the circumferential direction becomes large. The leak saturates.

FIGS. 6, 7 and 8 show the results of the magnetic field analysis for the rotor having the analysis target area shown in FIG. 5. In this case, in order to examine the leakage of magnetic flux from the rotor by the retaining ring 7, The stator slot was omitted and only the core was used.
Further, since the magnetic flux distribution is symmetric about the center of the magnetic pole, the examination is performed with one pole of 1/2 pole (analysis target area of FIG. 5) shown in FIG.

FIG. 6 is a magnetic flux diagram when a retaining ring of SUS630 according to this embodiment is used, and FIG. 7 is a magnetic flux diagram when a magnetic material of S45C, which is the same material as the rotor core, is used as a retaining ring. FIG. 4 is a magnetic flux diagram when a retaining ring made of a non-magnetic material is used. The magnetic flux density distribution on the inner surface of the stator core obtained by the analysis is 0.75 (T) in the present embodiment in the case of FIG. 6, 0.65 (T) in the retaining ring of S45C shown in FIG. 7, and the nonmagnetic property shown in FIG. The material retaining ring has a magnetic flux density of 0.59 (T), which is 1.27 times larger in the present embodiment than in the conventional case. That is, the amount of magnetic flux interlinking with the radial stator is large, in other words, it is possible to suppress a slight decrease in the amount of magnetic flux.

Returning to FIG. 2, the stator core 2 is provided with the slots 3a and the teeth 2a alternately, so that the permeance of the air gap changes. That is, the air gap magnetic flux concentrates on the portion corresponding to the tooth 2a, and the tooth 2a and the slot 3
It is general that the magnetic flux density distribution changes abruptly with a. However, in this embodiment, since the retaining ring 7 is provided on the surface of the permanent magnet 6, the magnetic flux passing through the teeth 2a is smoothly distributed in the retaining ring 7, and thus the rate of change in magnetic energy becomes small and the cogging torque is reduced. Becomes smaller.

Further, paying attention to the closed magnetic circuit of the field, the permanent magnet 6
As a magnetomotive force source, the retaining ring 7, the gap 9, the stator core 2,
Considering a magnetic circuit including the rotor core 5, a retaining ring 7 that is a magnetic material that has a thickness in the radial direction and is continuous in the circumferential direction.
Is arranged in series with the permanent magnet 6, the permanent magnet 6
The permeance of the external magnetic circuit as viewed is constant regardless of the rotational position. Therefore, the cogging torque becomes small.

Further, in the magnetic circuit state of the rotating electric machine, the operating point on the magnetic characteristic curve (magnetic flux density vs. magnetizing force characteristic) of the permanent magnet 6 is almost constant, and the magnetic loss (hysteresis loss etc.) of the permanent magnet material. Becomes smaller.

As described above, in this embodiment, the retaining ring 7 having the selected magnetic characteristics is arranged on the surface of the permanent magnet 6, so that the magnetic flux amount is not reduced, the cogging torque is suppressed, and the magnetic loss can be reduced.

Next, FIG. 9 shows a second embodiment. In the second embodiment shown in FIG. 9, the permanent magnet 6 serving as a field is provided with a gap between the poles, and a new permanent magnet 10 is arranged therebetween. Then, the magnetization direction of the new permanent magnet 10 in this inter-pole portion is substantially perpendicular to the magnetization direction of the original permanent magnet 6, and the polarity is the same as the pole on the side of the air gap 9 of the permanent magnet 6 and the permanent magnet. The pole of the new permanent magnet 10 on the side of the pole contacting with 6 is made the same pole.

Since the magnetic flux of the new permanent magnet 10 in the inter-pole portion is directed toward the end side surface of the original permanent magnet 6, the leakage flux of the original permanent magnet 6 along the retaining ring 7 becomes a new permanent magnet. The magnetic flux in the direction opposite to the magnetic flux of the magnet 10 is caused. Therefore, the magnetic flux that is about to leak is repelled by the inter-electrode magnet 10 and passes through the air gap to interlink with the stator core 2. Therefore, the effective magnetic flux amount further increases.

FIG. 10 shows an actual analysis result. As described above, the magnetic flux that is about to leak from the permanent magnet 6 is repulsed by the new permanent magnet 10 in the inter-electrode portion and is linked to the stator core 2. . In this embodiment, it is about 1.3 times larger than the conventional one. Also in this embodiment, mechanical fixing at the time of resistance to ultra-high speed and resistance to high temperature is sufficient, and cogging torque and magnetic loss have the same effects as those of the first embodiment.

Although two poles are illustrated in both the first and second embodiments, the same applies to a multi-pole type and a permanent magnet type linear motor. As an application of this embodiment, FIG.
The permanent magnet 6 and the retaining ring 7 provided on the inner peripheral side of the yoke 14 of the outer rotor 13 and the outer peripheral side of the yoke 16 of the inner rotor 15 can be applied to the magnetic coupling between the drive motor and the fan. The permanent magnet 6 and the retaining ring 7 provided in the above can be applied to each other. In addition, 17 is a partition.

Thus, in the first and second embodiments,
Not only can it sufficiently withstand centrifugal force at both ultra-high speed rotation and high temperature environment to mechanically firmly fix the permanent magnet to the rotor surface, but the holding ring of this embodiment can reduce the air gap magnetic flux density to only a small amount. Does not fall.

In addition, the cogging torque and the magnetic loss can be reduced by the retaining ring in terms of characteristics, and a permanent magnet type rotating electric machine with excellent characteristics can be obtained. In the first and second embodiments described above, the effect of reducing the cogging torque and the magnetic loss was obtained mainly with the aim of suppressing the air gap magnetic flux density. However, in the following embodiments, the cogging torque is suppressed. Is the main focus.

FIG. 12 shows a third embodiment, and exemplifies a rotor 4 provided with a 4-pole permanent magnet 6 on a rotor core 5 made of, for example, a magnetic material of S45C. In FIG. 12, teeth 2a and slots 3a are alternately formed on the inner circumference of an iron core 2 made of a silicon steel plate of the stator 1 facing the rotor 4. The coil 3 is accommodated in the slot 3a, and a magnetic wedge 20 is provided in the opening portion of the slot 3a for pressing and fixing the coil 3.

Here, the magnetic wedge 20 has a structure in which wedge small pieces 21 that are long in the direction of the rotation axis are laminated in the circumferential direction as shown in FIG. 13, and is made of a silicon steel plate of a soft magnetic material having a thickness of about 1 mm to 2 mm. The magnetic wedge 20 has a magnetic flux density of 0.5.
4 to 0.8 (T), the relative magnetic permeability is 100 or more, the magnetic flux density is 1.6 (T) or more, and the relative magnetic permeability is close to 10. The magnetic material may be SUS630 as shown in FIG. .

Further, as the material of the other magnetic wedge 20, the Co-based amorphous material 10 μm to 30 μm shown in FIG. 14 is used.
You may use what laminated about 100 layers. Further, as the shape of the magnetic wedge 20, as shown in FIG. 15, a wedge small piece 21 which is long in the circumferential direction may be laminated in the rotational axis direction.

FIG. 16 shows a fourth embodiment, and FIG.
Instead of the magnetic wedge 20 at the opening portion of the slot 3a shown in FIG. 3, a magnetic cylindrical body 22 is closely arranged and fixed to the inner peripheral surface of the rotor core 5.

The structure of the magnetic cylinder 22 is as follows.
As shown in FIG. 17, a wedge small piece 23 that is long in the rotation axis direction is laminated in the circumferential direction, or as shown in FIG. 18, circular thin plates 23 of a size that closely adheres to the inner peripheral surface of the rotor core are laminated in the axial direction. There is something.

The material of the magnetic cylindrical body 22 is the same as in the third embodiment, in the case of the silicon steel plate of soft magnetic material,
In the case of a magnetic material such as SUS630 having a magnetic flux density of 0.5 to 0.8 (T) and a relative magnetic permeability of 100 or more and a magnetic flux density of 1.6 (T) or more and a relative magnetic permeability of approximately 10, or The case of Co-based amorphous is used. In the case of amorphous, 100 μm to 10 μm to 30 μm is used.
A spirally wound layer may be used.

As a method of laminating the wedge small pieces 21 and 23 and the circular thin plate 23, there are methods of electron beam welding, laser welding, integral molding using an adhesive and resin. In the third and fourth embodiments, the magnetic wedge 20 and the cylindrical body 2 are used.
Without 2, the stator core 2 has slots 3a and teeth 2a.
Since the and are alternately formed, the magnetic resistance of the air gap changes, the air gap magnetic flux concentrates on the portion facing the tooth 2a, and the magnetic flux density distribution changes abruptly between the tooth 2a and the slot 3a. In this embodiment, the magnetic wedge 20 and the cylindrical body 22 make the magnetic resistance along the circumferential direction of the air gap relatively uniform. FIG. 19 shows the air gap magnetic flux density distribution which is the result of simulation by magnetic field analysis. As shown by the dotted line and the one-dot chain line in FIG. 19, the magnetic flux density distribution of the conventional permanent magnet type rotary electric machine has a large drop due to the slot 3a, but in the rotary electric machine of this embodiment shown by the solid line, it depends on the slot 3a of the air gap magnetic flux density. The drop is alleviated and the magnetic flux density distribution is smooth.

Therefore, the cogging torque becomes very small, and the rotational electric machine has reduced rotational fluctuation and output fluctuation. At the same time, the eddy current generated in the permanent magnet or the like is reduced due to the change in the magnetic resistance of the slot 3a and the tooth 2a.

Next, consider a magnetic circuit including the permanent magnet 6, the air gap 9, the stator core 2, and the rotor yoke, using the field permanent magnet 6 as a magnetomotive force source. Due to the wedge 20 and the cylindrical body 22, the inner diameter surface of the armature has a continuous magnetic material in the circumferential direction when viewed from the permanent magnet 6, and the permeance of the external magnetic circuit viewed from the permanent magnet 6 is constant regardless of the rotational position. . Therefore, the operating point on the magnetic characteristic curve (magnetic flux density vs. magnetizing force characteristic) of the permanent magnet 6 is almost constant, and the magnetic loss (hysteresis loss, etc.) of the permanent magnet 6 is small.

From the above, the cogging torque and the slot 3a
It is possible to provide a permanent magnet type rotating electric machine with excellent characteristics that suppresses the loss due to. In addition, the reduction of the effective magnetic flux is suppressed also in this embodiment.

The operation when the rotary electric machine of this embodiment is in a no-load state will be described. When the ultrathin silicon steel sheet, the amorphous magnetic material, and the magnetic material of SUS630 material of this embodiment are applied, a part of the magnetic flux (circumferential component) is the part of the inner diameter of the iron core (tooth 2).
a and the wedge 20 portion or the magnetic cylindrical body 22) flow along the circumferential direction, but the amount of magnetic flux increases because the leakage magnetic flux generated from the magnet gathers as it approaches the interpolar portion between the N pole and the S pole. The wedge 20 or the magnetic cylindrical body 22 near the gap
Has a magnetic flux density of about 1.5 to 3 (T) and is magnetically saturated. For example, in the case of the wedge 20 or the cylindrical body 22 of the SUS630 of the present invention, the SUS630 material is 1.6 as shown in FIG.
Above (T), the relative permeability becomes close to 10, and the magnetic resistance in the gap between the electrodes becomes considerably large, so leakage of magnetic flux in the circumferential direction is saturated with a small amount.

Therefore, the magnetic flux leaking in the gap between the electrodes is suppressed to a small amount, and the reduction of the effective magnetic flux interlinking with the coil 3 can be suppressed. On the other hand, regarding the magnetic flux in the radial direction, since the air gap magnetic flux density of the permanent magnet type rotary electric machine is 0.6 to 1 (T), the wedge 20 and the cylindrical body 22 of the present invention excluding the vicinity of the gap are magnetically saturated. Therefore, the decrease in the amount of magnetic flux interlinking with the coil 3 is slight. For example, the air gap magnetic flux density is magnetically designed to be near 0.8 (T), and the wedge 20 or the cylindrical body 22 is made of SUS.
In the case of the rotary electric machine of 630, when the wedge 20 or the cylindrical body 22 of the present invention is used, as shown in FIG.
8 (T), the relative permeability of the wedge 20 or the cylindrical body 22 is 120, and the wedge 20 in the radial direction of the magnetic pole portion,
Alternatively, the cylindrical body 22 does not form a magnetic gap, and the decrease in magnetic flux density is slight.

Next, considering the load state in which a current is applied to the coil 3, the coil 3 at the position where the field magnetic flux is in the maximum state (opposed to the center of the field magnetic pole) in the brushless DC motor.
Since the maximum current flows through the armature, the point where the magnetic flux created by the armature is maximum is near the magnetic poles of the field, and the wedge 2 near the interpolar portion is used.
0, the magnetic flux density of the cylindrical body 22 is large, and magnetic saturation is more likely to occur than when there is no load. Therefore, no load,
The magnetic flux leaking in the gap between the electrodes is suppressed to a small amount even when the load is applied, and the reduction of the effective magnetic flux interlinking the coil 3 can be suppressed.

When an amorphous magnetic material is used, the amorphous material has a magnetic flux density of 1 (T) or less and a magnetic permeability of about 5,000 to 200,000, which is extremely high and has a magnetic flux density of 1 to 1. Magnetic saturation occurs at 2 (T). As shown in FIG. 14, the Co-based amorphous material used in this example has a magnetic permeability of 10,000 to 200,000 and a saturation magnetic flux density of 1 to 1.2 (T) in the range of magnetic flux density of 0.3 to 1 (T). ) Is about.

Therefore, magnetic saturation in the vicinity of the interelectrode portion due to leakage flux in the circumferential direction occurs even if the amount of leakage flux is small, so the amount of interlinkage magnetic flux is slightly reduced. On the other hand, since the amorphous magnetic permeability is extremely high in the part where the amorphous material is present other than between the electrodes, cogging torque hardly occurs,
Electromagnetic losses are negligible.

When the rotor rotates at a high speed, in the case of a multi-pole rotating electric machine, an eddy current is generated in the magnetic wedge 20 and the magnetic cylindrical body 22 to cause a loss. Therefore, the magnetic wedge 2
0, the magnetic cylinder 22 is divided and laminated in parallel to the field magnetic flux of the rotor to reduce the eddy current.

As described above, by using the present invention, the magnetic flux amount of the field interlinking with the radial stator can be suppressed to a slight decrease. Therefore, the cogging torque can be increased without increasing the volume of the rotating electric machine. It is possible to provide a permanent magnet type rotating electric machine with reduced electromagnetic loss.

In the present invention, the rotary electric machine of the permanent magnet type rotating field has been described, but the same effect can be obtained by using the permanent magnet field magnet on the stator side represented by a DC motor and the rotary armature on the rotor side. Further, although the permanent magnet type rotary electric machine is described in the present embodiment, a permanent magnet type linear motor can be similarly used. Further, when priority is given to reduction of torque pulsation rather than reduction of output due to magnetic flux leakage between the surface of the field pole and the surface of the armature, the present invention can be applied to a general winding type synchronous machine.

[0063]

As described above, the rotary electric machine of the permanent magnet field according to the present invention suppresses the radial magnetic flux amount of the field interlinking with the stator coil to a slight decrease, and increases the volume of the rotary electric machine. It is possible to provide a permanent magnet type rotating electric machine having excellent characteristics in which the cogging torque generated by the slots and teeth of the armature core and the electromagnetic loss due to the slots are reduced.

[Brief description of drawings]

FIG. 1 is a sectional view of a rotary electric machine according to a first embodiment of the present invention, taken along the axial direction.

FIG. 2 is a partial cross-sectional view taken along the line AA of FIG.

FIG. 3 is a magnetic characteristic diagram of a retaining ring.

FIG. 4 is a characteristic diagram showing a relationship between magnetic permeability and magnetic flux density of magnetic materials (SUS630, S45C).

FIG. 5 is an explanatory diagram of an analysis target area of a rotor.

FIG. 6 is a magnetic flux diagram showing an analysis result of a retaining ring of SUS630.

FIG. 7 is a magnetic flux diagram showing the analysis result of the retaining ring in S45C.

FIG. 8 is a magnetic flux diagram showing an analysis result of a retaining ring made of a non-magnetic material.

FIG. 9 is a cross-sectional view of a rotor according to a second embodiment of the present invention cut along the radial direction.

FIG. 10 is a magnetic flux diagram showing an analysis result of the configuration according to FIG. 9 using a retaining ring of SUS630.

FIG. 11 is a configuration diagram applied to a magnetic coupling.

FIG. 12 is a sectional view of a rotary electric machine according to a third embodiment of the present invention, taken along the radial direction.

FIG. 13 is a configuration diagram of an example of a magnetic wedge in which small pieces that are long in the axial direction are stacked.

FIG. 14 is a magnetic characteristic diagram of an amorphous magnetic material.

FIG. 15 is a configuration diagram of an example of magnetic wedges stacked in the axial direction.

FIG. 16 is a sectional view of a rotary electric machine according to a fourth embodiment of the present invention.

FIG. 17 is a configuration diagram of a cylindrical body in which small pieces that are long in the axial direction are stacked.

FIG. 18 is a configuration diagram of a cylindrical body in which discs are laminated.

FIG. 19 is a void magnetic flux density distribution diagram for one pole, which is the result of magnetic field analysis.

FIG. 20 is a configuration diagram of a rotary electric machine using a conventional non-magnetic retaining ring.

FIG. 21 is a configuration diagram when a conventional magnetic wedge is used.

[Explanation of symbols]

 1 stator 2 stator iron core 2a tooth 3 coil 3a slot 4 rotor 5 rotor iron core 6,10 permanent magnet 7 retaining ring 9 void 20 magnetic wedge 21 wedge small piece 22 cylindrical body 23 wedge small piece (circular thin plate)

Claims (9)

[Claims] 1. A holding ring made of a magnetic material having a low saturation magnetic flux density, and a stator used as an armature by winding a coil around a magnetic material iron core, and a permanent magnet arranged in a circumferential direction of a surface of the magnetic material iron core. A permanent magnet type rotating electrical machine having a rotor fixed and covered with. 2. The retaining ring has a magnetic flux density of 0.5 to 0.8.
2. The permanent magnet according to claim 1, wherein the permanent magnet is made of a magnetic material having a magnetic characteristic of having a relative magnetic permeability of 100 or more at (T) and a relative magnetic permeability of 100 or less at a magnetic flux density of 1.6 (T) or more. Rotary electric machine. 3. A new permanent magnet is further arranged in the interelectrode portion of the permanent magnet arranged in the circumferential direction of the surface of the iron core of the magnetic material, and the magnetization direction of this new permanent magnet forms the interelectrode portion. The permanent magnet type rotating electric machine according to claim 1 or 2, wherein the permanent magnet type rotating electric machine and the permanent magnet are arranged so as to be orthogonal to the magnetization direction of the permanent magnet. 4. A permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed therein, and a rotor having a permanent magnet arranged on the surface of the iron core, wherein the opening of the slot is made of a silicon steel plate. A permanent magnet type rotating electric machine having a magnetic wedge. 5. A permanent magnet type rotating electric machine having a stator having an iron core having slots and teeth formed therein, and a rotor having permanent magnets arranged on the surface of the iron core, wherein an opening of the slot is made of an amorphous magnetic material. A permanent magnet type rotating electric machine having a magnetic wedge. 6. A permanent magnet type rotary electric machine comprising: a stator having an iron core having slots and teeth formed therein; and a rotor having a permanent magnet arranged on the surface of the iron core, wherein the magnetic flux density is 0 at the opening of the slot. .5-0.8
A magnetic wedge made of a soft magnetic material having magnetic characteristics of (T) having a relative magnetic permeability of 100 or more, a magnetic flux density of 1.6 (T) or more and a relative magnetic permeability of 100 or less is arranged. Permanent magnet type rotating electric machine. 7. A permanent magnet type rotating electric machine comprising: a stator having an iron core having slots and teeth formed on the inner periphery thereof; and a rotor having permanent magnets arranged on the surface of the iron core. A permanent magnet type rotating electric machine, characterized in that a cylindrical body of a silicon steel plate is arranged facing the rotor. 8. A permanent magnet type rotating electric machine comprising: a stator having an iron core having slots and teeth formed on the inner circumference thereof; and a rotor having permanent magnets arranged on the surface of the iron core. A permanent magnet type rotating electric machine, wherein a cylindrical body formed by winding an amorphous magnetic material in a spiral shape is arranged to face the rotor. 9. A permanent magnet type rotary electric machine comprising: a stator having an iron core having slots and teeth formed on the inner circumference thereof; and a rotor having a permanent magnet arranged on the surface of the iron core. Facing the rotor, the magnetic flux density is 0.5 to 0.8 (T), the relative magnetic permeability is 100 or more, and the magnetic flux density is 1.6 or more and the relative magnetic permeability is 10 or more.
A permanent magnet type rotating electric machine comprising a cylindrical body of a soft magnetic material having a magnetic characteristic of 0 or less.