JP2001161052A - Permanent magnet rotary machine and permanent magnet wind power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a permanent magnet rotary machine and a permanent magnet wind power generator having improved rotation efficiency and power generation efficiency, by smoothly and continuously changing a magnetic flux linkage of a stator from a permanent magnet depending on the number of rotations without requiring complicated structure or control. SOLUTION: A magnetic field is applied to a rotor 2 with a permanent magnet 3 mounted to a rotating shaft 1. Meanwhile, a stator 4 is provided at the flux linkage position of the rotor 2 to change the relative position in the axial direction of the rotator 2 and the stator 4 depending on an external force in the axial direction, and to generate a spring force in the axial direction depending on the movement in the axial direction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a rotating machine using a permanent magnet and a wind generator using the rotating machine.

[0002]

2. Description of the Related Art In a permanent magnet type rotating machine, since a magnetic flux amount of a magnet is constant, iron loss is generated in a stator core by rotation of a rotor. The efficiency of a rotating machine is expressed as output / (output + mechanical loss + iron loss + copper loss). In the low rotation speed range, iron loss is large and rotation efficiency is low.

On the other hand, the energy that can be extracted from the wind by the wind power generator rises at the third power of the wind speed. However, in a design in which the amount of permanent magnets is increased in accordance with the rated output, iron loss is large in a weak wind region. Power generation efficiency is low.

On the other hand, in a high-speed region where the wind speed is equal to or higher than the design value, the generated voltage is too high, and the inverter circuit cannot be controlled.

[0005] As a conventional known example for solving such a problem, as described in Japanese Patent Application Laid-Open No. Hei 10-318120, a wind power generator is provided with a plurality of generators, and when the wind is weak, the number of operating generators ( Ratio).

More specifically, in the wind generator described in this publication, a plurality of generators each having an armature as a stator and a permanent magnet as a rotor are connected in series to a power shaft that rotates in conjunction with the wind turbine. The number of generators operated is appropriately increased or decreased according to the wind energy, and when wind energy exceeding the limit is input, at least a part of the generator is operated as a brake to reduce the wind energy efficiency. We use well.

[0007]

However, the wind power generator having the above-described structure includes a rotation sensor for detecting the number of rotations of the power shaft, an inverter or a control element for controlling each generator according to a signal from the rotation sensor. From what you need,
The number of parts increases and the manufacturing cost increases.

In addition, since the output is adjusted by operating / non-operating the generator rotor unit, a device for connecting / disconnecting windings is required. Since this occurs as a disturbance, a device for suppressing harmonics is required.

The present invention has been made in view of the above-mentioned problems of the prior art, and does not require a complicated configuration or control, and links a permanent magnet to a stator in accordance with the number of revolutions. It is an object of the present invention to provide a permanent magnet type rotating machine and a permanent magnet type wind power generator having improved rotation efficiency and power generation efficiency by changing the generated magnetic flux steplessly and smoothly.

[0010] Another object of the present invention is to provide a wind power generator that appropriately generates power according to the wind speed without preparing a plurality of stators and rotors.

[0011]

According to a first aspect of the present invention, there is provided a permanent magnet type wind power generator, comprising: a rotating shaft integrally rotating with a blade; A rotor which is attached to the rotor and is magnetized by a permanent magnet, a stator provided at a position where the magnetic flux of the rotor interlinks, and means for changing an axial relative position between the stator and the rotor. It is characterized by having.

According to a second aspect of the present invention, there is provided a permanent magnet type rotating machine, comprising: a rotor attached to a rotating shaft and being magnetized by a permanent magnet; and a stator provided at a position where the magnetic flux of the rotor interlinks. The relative position of the rotor and the stator in the axial direction is changed according to the external force in the axial direction, and the spring force is generated in the axial direction according to the amount of axial movement.

[0013] Further, a permanent magnet type rotating machine according to a third aspect of the present invention includes a rotor attached to a rotating shaft and magnetized by a permanent magnet, and a stator provided at a position where the magnetic flux of the rotor interlinks. A disc spring disposed substantially perpendicular to the axial direction of the rotating shaft and connecting the rotor and the stator so as to be relatively movable in the axial direction.

The invention according to a fourth aspect is characterized in that an electromagnet for generating an attractive force in the axial direction of the rotating shaft is further provided.

A fifth aspect of the present invention is a permanent magnet type wind generator using the permanent magnet type rotating machine having the above-described configuration.

According to a sixth aspect of the present invention, a permanent magnet type rotating machine having the above structure is used, and in a low speed range from the start, a magnetic flux linked from the permanent magnet to the stator is reduced as compared with a rated time. This makes the electromotive force constant smaller than that at the time of rating.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. Embodiment 1 FIG. 1 and 2 show Embodiment 1 of the present invention.
And a rotor 2 attached near the rear end of the rotating shaft 1 and rotating integrally with the rotating shaft 1, a permanent magnet 3 attached to the rotor 2, A stator core 4 separated from the permanent magnet 3 by a predetermined distance;
And a frame 5 for fixing the same. Frame 5
The rotary shaft 1 is connected to the support 8 via a bearing 9 through a movable guide 6 and a linear moving mechanism 7. A blade 10 that rotates integrally with the rotating shaft 1 is attached to the front end of the rotating shaft 1.

In the above configuration, when the wind power generator G1 is rated, as shown in FIG.
In a state in which the stator core 4 and the stator core 4 are completely opposed (a state in which the center positions in the axial direction match), the rotating shaft 1 and the blade 10 rotate integrally. However, when it is desired to reduce the magnetic flux linked from the permanent magnet 3 to the stator coil 11 wound around the stator core 4, as shown in FIG. , The facing area between the permanent magnet 3 and the stator core 4 is reduced.

That is, when it is desired to reduce iron loss in a low-speed low-power area such as a light wind state, or in a high-speed area where the rotation speed increases in a strong wind state, the voltage generated by the wind power generator G1 may exceed the rating of the inverter element. In such a case, the power generation area is expanded by reducing the facing area between the permanent magnet 3 of the rotor 2 and the stator core 4 to reduce the magnetic flux linked from the permanent magnet 3 to the stator coil 11. Can be.

Embodiment 2 FIGS. 3 and 4 show a wind power generator G2 according to a second embodiment of the present invention. The movable guide 6 used in the wind power generator G1 according to the first embodiment shown in FIGS. Instead of the linear moving mechanism 7, a cylindrical disc spring 13 arranged substantially perpendicular to the axial direction of the rotating shaft 1 is used.

More specifically, the stator core 4 around which the stator coil 11 is wound is fixed to the rear inner surface of the cylindrical frame 5. 13 are fixed at their outer edges. A bearing 9 for rotatably supporting the rotating shaft 1 is fixed to the inner edge of the cylindrical disc spring 13, and the bearing 9 is attached to the cylindrical frame 5 via the disc spring 13 by the shaft of the rotating shaft 1. It is movably mounted in the direction.

In the wind power generator G2 having the above-described configuration, the cylindrical disc spring 13 is in the neutral position shown in FIG. 3 in a windless state, and when wind is received, the blade 10 is moved in the direction of arrow A shown in FIG. Rotate. When the wind is strong, the disc spring 13
Is deformed by wind pressure, and the bearing 9 supported on the cylindrical frame 5 via the disc spring 13 and the rotating shaft 1 rotatably mounted on the bearing 9 move in the direction of arrow B shown in FIG. As a result, the permanent magnet 3 of the rotor 2 and the stator core 4
And the area of the stator coil 1
The number of magnetic fluxes linked to 1 decreases.

Since the amount of movement of the rotor 2 in the axial direction changes in accordance with the wind speed, in a high-speed region in which the rotation speed of the generator may abnormally increase in a strong wind state, field weakening is performed. Moreover, this field adjustment is achieved passively without requiring any special control.

The disc spring 13 has an effect that the radial displacement of the rotating shaft 1 can be suppressed and a linear bearing is not required.

Embodiment 3 FIG. 5 shows a wind power generator G3 according to a third embodiment of the present invention. The wind turbine generator G3 according to the second embodiment shown in FIGS. The neutral position has been changed.

That is, at the neutral position of the cylindrical disc spring 13 shown in FIG. 5A, the permanent magnet 3 of the rotor 2 is at a position displaced relative to the stator core 4 in the axial direction. The number of magnetic fluxes linking from 3 to the stator coil 11 is reduced. When the wind starts to blow, the blade 10 rotates in the direction of arrow A as shown in FIG.
3 is slightly displaced by the wind pressure, and the bearing 9 and the rotating shaft 1 rotatably mounted on the bearing 9 move in the direction of arrow B. As a result, the permanent magnet 3 and the stator core 4 completely face each other, the facing area is maximized, and the linkage flux of the permanent magnet 3 increases. When the wind becomes strong, as shown in FIG. 5 (c), the cylindrical disc spring 13 is further displaced, the facing area between the permanent magnet 3 and the stator core 4 is reduced, and the linkage flux of the permanent magnet 3 is reduced. It decreases as compared with the state shown in FIG.

That is, when the blade 10 starts rotating in a light wind state, the permanent magnet 3 of the rotor 2 is at a position displaced in the axial direction with respect to the stator core 4, so that the electromotive force constant of the generator is rated. It is smaller than the time, and the iron loss generated in the stator is also small. Therefore, the rotation speed of the rotor 2 quickly increases, and power generation can be started even with a slight wind. That is, since the facing area between the permanent magnet 3 and the stator core 4 is reduced in the low-speed range, the wind speed at which power generation is started can be reduced.
Thereafter, when the wind becomes strong, the cylindrical disc spring 13 is displaced, and the facing area between the permanent magnet 3 and the stator core 4 is maximized, the interlinkage magnetic flux of the permanent magnet 3 is increased, and the power output of the generator is also increased. To rise. Further, in a high-speed region where the wind becomes stronger and the rotation speed increases, the facing area between the permanent magnet 3 and the stator core 4 decreases, so that an abnormal increase in the generator voltage during strong wind can be suppressed.

In the above-described configuration, the axial movement of the permanent magnet 3 with respect to the stator core 4 is performed only by the complete passive force of the wind pressure. However, as shown in FIG. An electromagnet 14 is attached to the rear end of the rotating shaft 1 opposite to the above, and the axial movement of the permanent magnet 3 with respect to the stator core 4 is actively controlled by using the attraction force of the electromagnet 14 generated by supplying power to the electromagnet 14. You can also.

That is, when power is not supplied to the electromagnet 14, the facing area between the permanent magnet 3 and the stator coil 11 is maximized as shown in FIG. While increasing the interlinkage magnetic flux, at the start of power generation or in a strong wind, the electromagnet 14
To the permanent magnet 3 as shown in FIG.
By adjusting the relative position of the permanent magnet 3 and the stator coil 11 in the axial direction, the flux linkage of the permanent magnet 3 with respect to the stator coil 11 can be appropriately reduced.

In the configuration shown in FIG. 6, the electromagnet 1
4 is attached to the rear end of the rotating shaft 1, but in the opposite manner, the movable iron core is attached to the rear end of the rotating shaft 1 and the electromagnet is attached to the rear wall 5 a of the frame 5. Needless to say, a great effect can be obtained.

As described above, by providing the electromagnet 14 that generates an attractive force in the axial direction, the relative position of the permanent magnet 3 and the stator coil 11 in the axial direction can be controlled not only by wind force but also electrically. This makes it possible to optimize the axial position of the rotor according to the wind speed.

Although the first to third embodiments have been described by taking the wind power generators G1, G2, and G3 as an example, the present invention can of course be applied to a permanent magnet type rotating machine. By applying the present invention, it is possible to provide a rotating machine having a simple configuration and capable of performing field control by axial movement.

[0033]

Since the present invention is configured as described above, it has the following effects. According to the first aspect of the present invention, since the means for changing the axial relative position between the stator and the rotor is provided, the field magnetic flux of the permanent magnet can be controlled, The power generation start voltage at the time can be set low. In addition, at the time of strong wind, it is possible to suppress an abnormal increase in the generator voltage.

According to the second aspect of the present invention, the relative position of the rotor and the stator in the axial direction is changed according to the external force in the axial direction, and the spring force is adjusted according to the amount of axial movement. Since the rotation is generated in the direction, a linear bearing for suppressing radial displacement of the rotating shaft is not required, and a rotating machine that can control the field by axial movement with a simple configuration can be provided.

According to the third aspect of the present invention,
A disc spring is disposed substantially perpendicular to the axial direction of the rotating shaft and connects the rotor and the stator so as to be relatively movable in the axial direction. Therefore, the radial displacement of the rotating shaft can be suppressed by the disc spring. In addition, it is possible to provide a rotating machine having a simple configuration and capable of performing field control by axial movement.

According to the fourth aspect of the present invention, since the electromagnet for generating the attraction force in the axial direction of the rotating shaft is further provided, the relative position of the rotor to the stator in the axial direction can be determined by using electricity. Can be arbitrarily controlled.

According to the fifth aspect of the present invention, since the permanent magnet type rotating machine according to any one of the second to fourth aspects is used for a wind power generator, the rotor is moved in the axial direction. The wind pressure received by the blades can be used as the driving power,
It is possible to provide a wind power generator that can control the field with a simple structure.

According to the invention described in claim 6, in the low speed range from the start, the magnetic flux interlinking from the permanent magnet to the stator is reduced as compared with the rated time, so that the electromotive force constant is reduced as compared with the rated time. Since the size is reduced, iron loss generated in the stator is reduced, and power generation efficiency is improved.

[Brief description of the drawings]

FIG. 1 is a schematic vertical sectional view of a wind power generator according to a first embodiment of the present invention, showing a state at the time of rating.

FIG. 2 is a schematic vertical sectional view of the wind power generator of FIG. 1, showing a state at a low speed or at a high speed.

FIG. 3 is a schematic vertical sectional view of a wind power generator according to a second embodiment of the present invention, showing a neutral state when there is no wind.

FIG. 4 is a schematic vertical sectional view of the wind power generator of FIG. 3, showing a case where a wind pressure is applied.

FIG. 5 is a schematic vertical sectional view of a wind power generator according to a third embodiment of the present invention, where (a) shows a neutral state when there is no wind;
(B) shows a state where the wind pressure is received, and (c) shows a state where the wind pressure is further increased.

FIG. 6 is a schematic longitudinal sectional view showing a configuration of an electromagnet that generates thrust in an axial direction in the present invention.

[Explanation of symbols]

Reference Signs List 1 rotation shaft, 2 rotor, 3 permanent magnet, 4 stator core, 5 frame, 5a rear wall, 6 movable guide, 7 linear moving mechanism, 8 support, 9 bearing, 10 blade, 11 stator coil, 13 cylinder Disc springs, 14 electromagnets, G1, G2, G3 wind generators.

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Mitsuhiro Kawamura, 2-3-2 Marunouchi, Chiyoda-ku, Tokyo Mitsui Electric Co., Ltd. (72) Inventor Masashi Nakano 2-3-2, Marunouchi, Chiyoda-ku, Tokyo F term (reference) 3H078 AA02 AA26 BB02 BB11 BB19 CC02 CC22 CC47 CC73 CC80 5H607 AA14 BB02 BB07 BB14 CC01 CC05 DD01 DD08 FF26 GG08 5H621 BB07 GA01 GA04 HH01 JK08 JK14 PP03

Claims (6)

[Claims] 1. A rotating shaft that rotates integrally with a blade, a rotor attached to the rotating shaft and fielded by a permanent magnet,
A stator provided at a position where the magnetic flux of the rotor interlinks;
A permanent magnet type wind power generator comprising: means for changing an axial relative position between the stator and the rotor. 2. A rotor attached to a rotating shaft and fielded by a permanent magnet, a stator provided at a position where magnetic flux of the rotor interlinks, and fixed to the rotor according to an external force in an axial direction. A permanent magnet type rotating machine that changes the axial relative position with respect to a child and generates a spring force in the axial direction according to the amount of axial movement. 3. A rotor attached to the rotating shaft and fielded by a permanent magnet, a stator provided at a position where the magnetic flux of the rotor interlinks, and a stator arranged substantially perpendicular to the axial direction of the rotating shaft. And a disc spring for connecting the rotor and the stator relatively movably in the axial direction. 4. The permanent magnet type rotating machine according to claim 2, further comprising an electromagnet for generating an attractive force in an axial direction of the rotating shaft. 5. A permanent magnet type wind power generator using the permanent magnet type rotating machine according to claim 2. 6. The permanent magnet type rotating machine according to claim 2, wherein in a low speed range from the start,
A permanent magnet wind generator in which the electromotive force constant is made smaller than at the rated time by reducing the magnetic flux linking from the permanent magnet to the stator as compared with the rated time.