JP2003299278A - Rotor for rotating machine and its manufacturing method, rotating machine and gas turbine power plant - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a rotor for a rotating machine which can increase an output and decrease in size by reducing an iron loss of a stator and a vibration at a rotating time, and to provide a method for manufacturing the same, the rotating machine and a gas turbine power plant. <P>SOLUTION: The rotor for the rotating machine comprises a shaft, a cylindrical permanent magnet disposed on an outer periphery of the shaft, and a cylindrical holding ring disposed on an outer periphery of the magnet. In this rotor, the magnet is Hallwachs magnetized. The ring is obtained by alternately forming a magnetic material and a nonmagnetic material in a circumferential direction of the outer periphery. In the rotor for the machine comprising a solid cylindrical permanent magnet and a cylindrical holding ring disposed on the outer periphery of the magnet, the magnet is Hallwachs magnetized, the ring is obtained by alternately forming the magnetic material and the nonmagnetic material in the circumferential direction of the outer periphery. Further, the method for manufacturing the same, the rotating machine using the same method and the gas turbine power plant are provided. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel rotary electric machine rotor having permanent magnets, a method for manufacturing the same, a rotary electric machine, and a gas turbine power plant.

[0002]

2. Description of the Related Art FIG. 10 is a sectional view of a conventional rotary electric machine rotor (conventional example 1). In this conventional example, a permanent magnet 2 is provided on the outer peripheral side of a shaft 1, and a retaining ring 3a is shrink-fitted or press-fitted on the outer peripheral side of the permanent magnet 2. Here, as the permanent magnet 2, a hollow-cylindrical integrated body or a hollow-cylindrical body formed by combining a plurality of magnets is used. The holding ring 3a is a ring for preventing the permanent magnets from scattering due to centrifugal force.
Non-magnetic materials such as i-based alloys, titanium alloys, and glass fiber reinforced plastics (CFRP) are used.

FIG. 11 is a sectional view of a rotor of a rotary electric machine described in Japanese Patent Laid-Open No. 10-23695 (Prior Art 2). The conventional example 2 is characterized in that the permanent magnet 2b is magnetized by radial magnetization and the holding ring is made of a magnetic material 3b and a non-magnetic material 3a.

[0004]

[Patent Document 1] Japanese Patent Laid-Open No. 10-23695

[0005]

In the conventional example 1 of FIG. 10, the distance from the stator (not shown) to the permanent magnet 2b, that is, the magnetic gap is increased by the amount of the retaining ring 3a made of a non-magnetic material. Therefore, there is a drawback that the electrical characteristics such as the induced voltage of the stator coil or the output of the generator are deteriorated.

Further, in the conventional example 2 of FIG. 11, in order to solve the problem of the conventional example 1, the retaining ring is composed of the magnetic material 3b and the non-magnetic material 3a, and the retaining ring is composed of the magnetic material 3b. Since the magnetic gap can be made smaller in the affected portion, there is an effect of preventing deterioration of electrical characteristics. However, in Conventional Example 2, the permanent magnet 2b is magnetized by radial magnetization, so that the magnetic flux density distribution in the gap has a square wave shape as shown in FIG. In this case, since the magnetic flux density distribution in the gap contains many harmonic components, problems such as an increase in iron loss of the stator and an increase in vibration during rotation occur.

To solve these problems such as an increase in stator iron loss and an increase in vibration during rotation, it is called hullback magnetization in which the magnetic flux density in the gap is sinusoidal as shown in FIG. 12 (b). A permanent magnet magnetization method is adopted. However, in the structure of the conventional example 1 using the permanent magnet adopting the Hullback magnetization, the distance from the stator to the permanent magnet, that is, the magnetic gap is increased by the amount of the holding ring made of a non-magnetic material. There is a drawback that the electrical characteristics such as the induced voltage or the output of the generator are reduced.

Further, when a hull-back magnetized permanent magnet is used in a structure as in Conventional Example 1, the characteristics shown in FIG.
As shown in Fig. 3, a small loop of the magnetic circuit is formed in the vicinity of the A portion, so that the magnetic flux density of the shaft becomes large in the vicinity of the A portion, and magnetic saturation may occur. In this case, the equivalent magnetic resistance of the magnetic circuit increases, which leads to deterioration in electrical characteristics such as the induced voltage of the stator coil or the output of the generator.

An object of the present invention is to provide a rotating electric machine rotor, a manufacturing method thereof, a rotating electric machine, and a gas turbine power plant, which can reduce iron loss of a stator and vibration during rotation, and can achieve high output and downsizing. Especially.

[0010]

SUMMARY OF THE INVENTION The present invention has a holding ring in which a permanent magnet adopting Hullback magnetization is provided on the outer circumference of a shaft, and a magnetic material and a non-magnetic material are alternately arranged on the outer circumference in the circumferential direction. A rotary electric machine rotor having a structure fixed by means of this structure, and this structure solves the above-mentioned various problems.

That is, by using a rotating electric machine rotor having a structure in which a permanent magnet adopting Hullback magnetization is provided on the outer periphery of the shaft, and a retaining ring made of a magnetic material and a non-magnetic material is fixed to the outside of the permanent magnet. Since the magnetic flux density of the gap is sinusoidal, the problem of increased stator iron loss and increased vibration during rotation is solved, and the magnetic gap in the portion of the retaining ring made of magnetic material is solved. Can be made smaller, so that deterioration of electrical characteristics can be prevented. Further, since the magnetic flux easily passes through the portion made of the magnetic material in the retaining ring, it becomes difficult to form the small loop of the magnetic circuit as shown in FIG.
Magnetic saturation of the shaft does not occur near the part. That is, the equivalent magnetic resistance of the magnetic circuit does not increase, and the deterioration of electrical characteristics can be prevented. As a result, higher output and higher efficiency of the rotary electric machine can be achieved.

According to the present invention, in a method of manufacturing a rotor of a rotary electric machine having a cylindrical permanent magnet and a cylindrical retaining ring on the outer circumference of a shaft, after the permanent magnet is oriented and shaped for hullback magnetization during sintering, The permanent magnet and the shaft are integrally assembled, and then the retaining ring in which a magnetic material and a non-magnetic material are alternately and integrally formed in the circumferential direction is press-fitted or shrink-fitted onto the outer circumference of the permanent magnet. To do. After the assembly of the rotor of the rotating electrical machine is completed, the permanent magnet is hull-back magnetized.

Furthermore, the present invention relates to a method for manufacturing a rotor of a rotary electric machine having an auxiliary ring, a cylindrical permanent magnet and a cylindrical retaining ring on the outer circumference of the shaft, wherein the permanent magnet is oriented for hullback magnetization during sintering. After molding, the auxiliary ring, the permanent magnet, and the retaining ring in which magnetic material and non-magnetic material are alternately and integrally formed in the circumferential direction are integrally combined, and then the shaft is pressed into the auxiliary ring inner diameter or Characterized by cold fitting. After the assembly of the rotor of the rotating electrical machine is completed, the permanent magnet is hull-back magnetized.

Further, according to the present invention, in a rotating electric machine having a stator around which a coil is wound and a rotor rotating in the stator, the rotor is any one of the rotors described above or a method of manufacturing the rotor. It is characterized by being constituted by a rotor manufactured by.

Furthermore, the present invention is a gas turbine power plant having a gas turbine and a generator driven by the gas turbine, wherein the generator is constituted by the rotating electric machine described above. In particular, the present invention is effective in a gas turbine power plant in which the diameter of the body of the rotor of the generator is preferably 50 to 300 mm and the rotation speed is preferably 2000 to 100000 rpm.

The permanent magnet is preferably one in which a hollow or solid cylindrical magnet is integrated, but a magnet having a hollow or solid cylindrical shape formed by fixing a plurality of magnets with an adhesive or the like is also the same. The effect is clear.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS (Embodiment 1) FIG. 1 is a sectional view of a rotor of a rotary electric machine of the present invention, which is intended for a two-pole magnetic pole. The arrow indicates the magnetization direction. In the first embodiment, in the rotating electric machine rotor including the shaft 1 serving as the central axis, the cylindrical permanent magnet 2a arranged on the outer circumference of the shaft, and the cylindrical holding ring 3 arranged on the outer circumference of the permanent magnet,
The permanent magnet 2a has the magnetic flux density of the gap shown in FIG.
The sinusoidal hull-back magnet shown in (b) is magnetized, and the retaining ring is made of a magnetic material 3b and a non-magnetic material 3a. With such a structure, since the magnetic flux density of the gap becomes sinusoidal, problems such as increased stator iron loss and increased vibration during rotation are solved.
Further, since the magnetic gap can be reduced by the amount of the retaining ring of the magnetic material, it is possible to prevent deterioration of electrical characteristics. Further, since the magnetic flux easily passes through the portion of the retaining ring made of the magnetic material, it is difficult to form a small loop of the magnetic circuit as shown in FIG. 13, and magnetic saturation of the shaft occurs near the portion A. Will not do. That is, the equivalent magnetic resistance of the magnetic circuit does not increase, and the deterioration of electrical characteristics can be prevented. As a result, higher output and higher efficiency of the rotary electric machine can be achieved.

In the rotor of the rotating electric machine of this embodiment, the permanent magnet and the shaft are integrally assembled, and then the holding ring in which a magnetic material and a non-magnetic material are alternately and integrally formed in the circumferential direction is used as the permanent ring. It is manufactured by press fitting or shrink fitting on the outer circumference of the magnet. After the assembly of the rotor of the rotating electric machine is completed, the permanent magnet is magnetized by Hullback.

Although the shaft 1 has a solid cylindrical shape in this embodiment, it is obvious that the same effect can be obtained with a hollow cylindrical shaft.

FIG. 2 is a sectional view of the rotor of the rotary electric machine of FIG. 1 taken in the longitudinal direction. As shown in FIG. 2, a cylindrical permanent magnet 2a and a permanent magnet 2a are provided on the outer periphery of the body of the shaft 1.
And a cylindrical retaining ring 3 disposed on the outer periphery of the retaining ring 3, and both sides are retained by the retaining rings 5. The shaft 1 has shaft portions on both sides of the body portion. The shaft 1 may be made of either a magnetic material made of low alloy steel or a non-magnetic material made of Ni-based alloy.

FIG. 3 is a cross-sectional view showing the flow of magnetic flux of a rotor of a rotary electric machine having a hull-back magnetized permanent magnet. As shown in FIG. 3, lines of magnetic force are concentrated on the magnetic material 3b, so that the portion with high magnetic flux density in the portion A shown in FIG. 13 is eliminated.

FIG. 4 is a sectional view of a rotary electric machine using the rotary electric machine rotor described in this embodiment. As for the stator, a slot 7 is provided in a stator core 6 made of a silicon steel plate, and a stator winding 8 is wound around the slot 7. Although not shown, it has a case and bearings provided at both ends.

In the retaining ring of the first embodiment, for example, when the outer diameter is 100 mm and the rotation speed is 50000 rpm, the maximum is 100.
Since a large tensile stress of a little less than 0 MPa may act, the material forming the retaining ring and the joint portion of these materials require a tensile strength of more than 1000 MPa. Therefore, diffusion bonding is considered to be effective as a method of coupling the magnetic material and the nonmagnetic material forming the retaining ring. When the magnetic material and the non-magnetic material forming the retaining ring are bonded by diffusion bonding, the work is performed by the procedure of diffusion bonding, solution treatment, and aging treatment. At this time, it is important that the heat treatment conditions of the solution treatment and the aging treatment are almost the same between the magnetic material and the nonmagnetic material. If the heat treatment conditions of the two are far from each other, not only the heat treatment cannot be performed at once, but there is also a problem that the strength of each of them is reduced near the boundary between the two because they are affected by the other heat treatment. Therefore, it is necessary to select a magnetic material and a non-magnetic material from the viewpoint that both heat treatment conditions are close to each other. As the magnetic material, maraging steel, stainless steel, or die steel, and as the non-magnetic material, a Ni-based alloy is used. Alternatively, a titanium alloy may be mentioned as a candidate material. In particular, a combination using maraging steel for the magnetic material 3b and a titanium alloy for the non-magnetic material 3a is preferable. Further, a sintered body of an intermetallic compound having a rare earth element such as NdFeB or SmCo is used for the cylindrical permanent magnet 2a.

On the other hand, if adhesion is adopted as the method of joining the magnetic material and the non-magnetic material forming the retaining ring, it is possible to perform a solution treatment, an aging treatment, and an adhesion procedure for each material. The difference in the heat treatment conditions does not pose a problem.

In order to avoid the problem of such coupling between the magnetic material and the non-magnetic material, there is a method of using a composite magnetic material capable of locally demagnetizing the retaining ring by heat treatment. For example, a ferritic stainless steel composite material exhibits ferromagnetism when heat-treated below the temperature of the ferrite (α) phase region, but exhibits non-magnetism when rapidly cooled by solution treatment above the temperature of the austenite (γ) phase region. If such a composite magnetic material is used for the retaining ring,
The problem of bonding between the magnetic material and the non-magnetic material does not occur, and there is no need to worry about reduction in strength due to defects on the bonding surface.

(Embodiment 2) FIG. 5 is a sectional view of a rotary electric machine rotor according to the present invention, which is intended for a two-pole magnetic pole. In the second embodiment, in the rotor of the rotating electric machine configured by the solid cylindrical permanent magnet 2a and the cylindrical holding ring arranged on the outer circumference of the permanent magnet, the permanent magnet 2a is hull-back magnetized, and the holding ring is It is formed of a magnetic material 3b and a non-magnetic material 3a. With such a structure, since the magnetic flux density of the gap becomes sinusoidal as in the first embodiment, problems such as increased stator iron loss and increased vibration during rotation are solved, and Since the magnetic gap can be reduced by the amount corresponding to the retaining ring of the magnetic material, it is possible to prevent deterioration of electrical characteristics. As a result, higher output and higher efficiency of the rotary electric machine can be achieved. Also in the second embodiment, the material, the manufacturing method, the magnetizing method and the like are the same as in the first embodiment, and the flow of the magnetic flux is formed in the direction perpendicular to the axis of the shaft 1 as shown in FIG. Has been done.

(Embodiment 3) FIG. 6 is a cross-sectional view of a rotor of a rotary electric machine according to the present invention, which has two magnetic poles. In the third embodiment, the non-magnetic auxiliary ring 4 is provided on the outer circumference of the holding ring formed of the magnetic material 3b and the non-magnetic material 3a. With this structure, there is a defect in the coupling part between the magnetic material and the non-magnetic material, and even if the coupling between the magnetic material and the non-magnetic material is broken, the rotor component does not scatter to the outside and it helps. Since it stays in the ring, it is possible to secure safety to the surroundings. The material of the auxiliary ring 4 is Ni-based alloy, titanium alloy, glass fiber reinforced plastic (CF
Non-magnetic materials such as RP) are preferred. Further, the configuration of the rotor and the configuration of the rotating electric machine are the same as in the first embodiment.

In the rotor of the rotating electric machine of this embodiment, the auxiliary ring, the permanent magnet, and the holding ring in which the magnetic material and the non-magnetic material are alternately and integrally formed in the circumferential direction are integrally combined, and then the shaft is formed. Is manufactured by press fitting or cold fitting into the inner diameter of the auxiliary ring. After the assembly of the rotor of the rotating electric machine is completed, the permanent magnet is magnetized by Hullback.

Also in the third embodiment, the materials other than the auxiliary ring 4 are the same as in the first embodiment, and the flow of the magnetic flux is formed in the direction perpendicular to the axis of the shaft 1 as shown in FIG. Has been done.

(Embodiment 4) FIG. 7 is a cross-sectional view of a rotor of a rotary electric machine of the present invention intended for two magnetic poles. In the fourth embodiment, the holding ring made of the magnetic material 3b and the non-magnetic material 3a has the non-magnetic auxiliary ring 4 on the inner and outer circumferences. With such a structure, the retaining ring surrounded by the auxiliary ring can be integrally manufactured, so that the strength of the retaining ring including the auxiliary ring is significantly increased as compared with the case where only the retaining ring is used. Further, as in the case of the third embodiment, even if the coupling portion between the magnetic material and the non-magnetic material has a defect and the coupling between the magnetic material and the non-magnetic material is broken, the constituent members of the rotor do not scatter to the outside and it is assisted. Since it stays in the ring, it is possible to secure safety to the surroundings. As a material for the auxiliary ring 4, a non-magnetic material such as a Ni-based alloy, a titanium alloy, or glass fiber reinforced plastic (CFRP) can be considered.

In the rotor of the rotating electric machine of this embodiment, the permanent magnet and the shaft are integrally assembled, and then the retaining ring and the retaining ring in which a magnetic material and a non-magnetic material are alternately and integrally formed in the circumferential direction. It is manufactured by press-fitting or shrink-fitting a ring in which a non-magnetic auxiliary ring is combined on the inner circumference and the outer circumference of the above, to the outer circumference of the permanent magnet. After the assembly of the rotor of the rotating electrical machine is completed, the permanent magnet is hull-back magnetized.

Also in this fourth embodiment, the materials other than the auxiliary ring 4 are the same as in the first embodiment, and the flow of the magnetic flux is formed in the direction perpendicular to the axis of the shaft 1 as shown in FIG. Has been done.

(Embodiment 5) FIG. 8 is a sectional view of a rotating electric machine rotor of the present invention having four magnetic poles. In this embodiment, the retaining ring 3 is made of a magnetic material 3b and a non-magnetic material 3.
4 and 4 are alternately arranged.

Also in the fifth embodiment, the material, the manufacturing method and the like are the same as in the first embodiment.

Even in the case of multiple poles such as 6 poles and 8 poles, the positional relationship between the magnetic material and the non-magnetic material of the retaining ring 3 is alternately changed corresponding to the number of poles as in this embodiment. The same effect can be obtained.

(Sixth Embodiment) FIG. 9 is a configuration diagram of a gas turbine power plant of the present invention using the rotor of the rotating electric machine described in the first to fifth embodiments. This plant is equipped with a compressor 9, a combustor 10, a gas turbine 11, and a generator 12, and waste heat emitted from the gas turbine 11 is recovered as steam by a waste heat recovery boiler, and the steam is a steam turbine or Used for heat such as heating.

The rotary electric machine rotor of this embodiment is effective for a high-speed generator of 20000 to 100000 rpm as described above, and reduces stator core loss and vibration during rotation to achieve high output and It is possible to provide a power plant that can be downsized.

[0038]

According to the rotor of the present invention, there is provided a hull-back magnetized permanent magnet of the present invention and a retaining ring formed on the outer periphery of the permanent magnet and made of a magnetic material and a non-magnetic material.
The magnetic flux density in the gap is sinusoidal, which solves the conventional problems of increased stator iron loss and increased vibration during rotation. Can be made smaller, so that deterioration of electrical characteristics can be prevented. Furthermore, because the magnetic flux easily passes through the part made of magnetic material in the retaining ring,
A small loop of the magnetic circuit is less likely to be formed, and magnetic saturation does not occur in a specific part of the shaft. That is, the equivalent magnetic resistance of the magnetic circuit does not increase, and the deterioration of electrical characteristics can be prevented. As a result, higher output and higher density of the rotating electric machine can be realized, and finally, the rotating electric machine can be downsized or the productivity can be improved.

[Brief description of drawings]

FIG. 1 is a sectional view of a rotating electric machine rotor of the present invention.

FIG. 2 is an overall sectional view of a rotary electric machine rotor of the present invention.

FIG. 3 is a cross-sectional view showing magnetic lines of force of the rotating electric machine rotor of the present invention.

FIG. 4 is a cross-sectional view of the rotating electric machine of the present invention.

FIG. 5 is a sectional view of a rotating electric machine rotor of the present invention.

FIG. 6 is a sectional view of a rotating electric machine rotor of the present invention.

FIG. 7 is a sectional view of a rotary electric machine rotor of the present invention.

FIG. 8 is a cross-sectional view of a rotating electric machine rotor of the present invention.

FIG. 9 is an overall configuration diagram of a gas turbine power generation plant using the rotating electric machine of the present invention.

FIG. 10 is a cross-sectional view of a conventional rotary electric machine rotor.

FIG. 11 is a sectional view of a conventional rotary electric machine rotor.

FIG. 12 is a diagram showing a relationship between a gap position of a rotating electric machine rotor and magnetic flux density.

13 is a cross-sectional view showing magnetic lines of force around the rotor of the conventional rotary electric machine of FIG. 11.

[Explanation of symbols]

1 ... Shaft, 2 ... Permanent magnet, 2a ... Permanent magnet (Halbach magnetized), 2b ... Permanent magnet (Radial magnetized), 3a ...
Retaining ring (non-magnetic material), 3b ... Retaining ring (magnetic material), 4 ... Auxiliary ring, 6 ... Stator core, 7 ... Slot, 8 ... Stator winding.

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Kazumasa Ide             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Mamoru Kimura             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Mori Yoshinobu             7-1-1, Omika-cho, Hitachi-shi, Ibaraki Prefecture             Inside the Hitachi Research Laboratory, Hitachi Ltd. (72) Inventor Kiyoshi Yamaguchi             3-1-1 Sachimachi, Hitachi City, Ibaraki Prefecture Stock Association             Hitachi, Ltd., Hitachi Works (72) Inventor Takashi Matsunobu             3-1-1 Sachimachi, Hitachi City, Ibaraki Prefecture Stock Association             Hitachi, Ltd., Hitachi Works F term (reference) 5H615 AA01 BB02 BB07 PP02 PP06                       SS18 SS26 TT04 TT23 TT26                 5H621 BB07 HH01 JK01 JK02 JK03                       JK13                 5H622 CA02 CA05 CA12 CB04 DD02                       PP03 PP19 QA02

Claims (13)

[Claims] 1. A rotary electric machine rotor having a shaft, a cylindrical permanent magnet arranged on the outer circumference of the shaft, and a cylindrical holding ring arranged on the outer circumference of the permanent magnet, wherein the permanent magnet is hull-backed. A rotating electrical machine rotor, wherein the retaining ring is magnetized, and a magnetic material and a non-magnetic material are alternately formed in a circumferential direction of the outer circumference. 2. A rotary electric machine rotor having a solid cylindrical permanent magnet and a cylindrical holding ring arranged on the outer circumference of the permanent magnet, wherein the permanent magnet is hull-back magnetized, and the holding ring. Is a rotor of a rotating electrical machine, wherein a magnetic material and a non-magnetic material are alternately formed in the circumferential direction of the outer circumference. 3. The rotor of a rotary electric machine according to claim 1, wherein the permanent magnet is made of an intermetallic compound-based sintered material containing a rare earth element. 4. A rotor for a rotating electric machine according to claim 1, wherein the magnetic material is maraging steel, stainless steel, or die steel, and the nonmagnetic material is a Ni-based alloy or a titanium alloy. 5. The rotor of a rotating electric machine according to claim 1, wherein the magnetic material and the non-magnetic material of the retaining ring are hollow cylinders joined by diffusion bonding or an adhesive. 6. The rotating electric machine rotor according to claim 1, wherein the retaining ring is a composite magnetic material that is locally demagnetized by heat treatment. 7. The rotor of a rotating electric machine according to claim 6, wherein the composite magnetic material is metastable austenite stainless steel or ferritic stainless steel. 8. The rotor of a rotating electric machine according to claim 1, wherein a cylindrical non-magnetic auxiliary ring is formed on the outer circumference of the holding ring or on the inner circumference and outer circumference thereof. 9. The rotor of a rotating electric machine according to claim 8, wherein the auxiliary ring is any one of glass fiber reinforced plastic, Ni-based alloy, titanium alloy and non-magnetic stainless steel. 10. A method of manufacturing a rotary electric machine rotor having a cylindrical permanent magnet and a cylindrical holding ring on the outer circumference of a shaft, wherein the permanent magnet and the shaft are integrally assembled to form a magnetic material and a non-magnetic material. A method for manufacturing a rotor of a rotary electric machine, comprising press-fitting or shrink-fitting the retaining rings, which are integrally formed alternately in the circumferential direction, on the outer periphery of the permanent magnet. 11. A method of manufacturing a rotor of a rotary electric machine having an auxiliary ring, a cylindrical permanent magnet, and a cylindrical holding ring on the outer circumference of a shaft, wherein the auxiliary ring, the permanent magnet, and a magnetic material and a non-magnetic material are surrounded. A method for manufacturing a rotor of a rotary electric machine, comprising: integrally combining the retaining rings, which are integrally formed alternately in a direction, and press-fitting or cold-fitting the shaft into the inner diameter of the auxiliary ring. 12. A rotating electric machine comprising a stator having a coil wound around a slot formed in an iron core, and a rotor rotating in the stator, wherein the rotor comprises the rotor according to claim 1. A rotating electric machine characterized by the above. 13. A power plant having a gas turbine and a generator driven by the gas turbine, wherein the generator comprises the rotating electric machine according to claim 12.