JP2013051818A - Power generator - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a multi-polar power generator for efficiently generating power at a small number of revolution and high efficiency without enlarging a structure of a rotation portion even when waste of a material is eliminated and the number of turns of a coil is increased.SOLUTION: A large number of stator poles 7 formed by applying a coil to an iron core around which a belt-like electromagnetic steel plate is wound are fixed to an outer peripheral side of a housing 5 at identical angular intervals. A cylindrical yoke 8 around which the belt-like electromagnetic steel plate is wound is in contact with outer peripheries of the stator poles 7. A rotor 16 having a large number of permanent magnets are inserted in the housing 5, and rotates by a rotation shaft 2. The rotation shaft 2 is supported by a bearing fixed to the housing. The iron cores of the stator poles 7 are manufactured by applying the coil to the iron core around which the belt-like directional electromagnetic steel plate is wound, and therefore, waste of a material can be saved. Also, the stator poles 7 and the yoke 8 are manufactured separated, and fixation of the stator poles 7 is supported on the outer peripheral side of the housing 5, so that structural strength can be held at a position near a magnetic gap.

Description

The present invention relates to a generator that generates power by being coupled to a low-speed output shaft such as a windmill.

The frequency of commercial electric power is 50 Hz (or 60 Hz). For example, in turbine power generation using a two-pole rotor in thermal power / hydroelectric power generation, high-speed rotation of 3000 rotations / minute is required (3600 rotations / minute in the case of 60 Hz). However, in a wind turbine using wind power, high-speed rotation cannot be expected, and the number of rotations is increased by a gear or a multipolar rotor generator is used. With a 20-pole rotor, commercial power frequency power can be obtained even at a low speed of 300 revolutions / minute, and gearless power generation becomes possible.

For example, Patent Document 1 discloses a multipolar generator. This generator has a rotor having permanent magnets as magnetic poles and a radiation-shaped stator, and generates an AC voltage in an armature winding wound around the stator by rotating the rotor.

JP 2000-60092 A JP 2005-304127 A

Regarding the manufacture of a motor including a generator, a magnetic material is stamped and formed in order to form a stator having a radial teeth. In the generator of Patent Document 1, if the number of turns of the winding is increased, the length of the radial tasting must be increased, and if formed by punching the core, a large amount of material between the tastings is wasted. .
In addition, when the length of the tasse is long and the rotor diameter is large with a multi-pole configuration, a large bending moment is generated at the end of the long tas (connecting portion with the yoke) according to the principle of the lever, and this is corresponding to this. In addition, the connecting portion between the tas and the yoke is strongly thickened. Therefore, a large and strong casing is required to accommodate the tases and rotors thus enlarged. On the other hand, if the tasse is lengthened, many windings can be wound, but conversely, in order to give the mechanical strength of the tass themselves, the width must be further increased. As a result, the conductor length increases and the copper loss increases.

Incidentally, in Patent Document 2, regarding the formation of a cylindrical rotor core for fixing a permanent magnet, it has been proposed to form a rotor core by winding a rectangular parallelepiped ferromagnetic material instead of punching. It is not disclosed about a stator having a tee.

Therefore, the present invention eliminates the waste of material generated during punching by forming the radial core from a sheet-like soft magnetic material, and further increases the structure of the rotating part even if the number of turns of the winding is increased. It aims at providing the generator which is not made to become.

In order to solve the above-mentioned problems, the generator of the present invention includes a large number of stator poles wound on an iron core wound with a belt-shaped electromagnetic steel sheet, and the stator poles are fixed to the outer peripheral surface side at equal angular intervals. A non-magnetic housing with one end of the magnetic circuit of the stator pole facing the inner peripheral surface side, a yoke with the other end of the stator pole in contact with a cylindrical inner peripheral surface wound with a strip-shaped electromagnetic steel sheet, and A rotor having a plurality of magnetic poles formed by permanent magnets inserted into the housing and forming a magnetic gap with one end of the magnetic circuit of the stator pole facing the inner peripheral surface of the housing; and rotating the rotor It has a rotating shaft and a bearing that supports the rotating shaft and is fixed to the housing.

According to the present invention, since the iron core of the stator pole is manufactured by winding the iron core around which the belt-shaped electromagnetic steel sheet is wound, there is an effect that waste of material can be saved. Further, the stator pole and the yoke are manufactured separately, and the stator pole is fixed on the outer peripheral surface side of the housing. And since a housing is fixed to a bearing, the structural intensity | strength as a generator can be given to the position near a magnetic gap. Therefore, even if the length of the stator pole is increased and the number of windings is increased, the stator pole can be supported near the magnetic gap.

FIG. 1 shows a generator 1 of this embodiment. The generator 1 is an inner rotor type, and a rotor (described later) having a permanent magnet as a magnetic pole is fixed to the rotating shaft 2 and rotates in a non-magnetic stainless steel housing 5. The housing 5 is fixed to the front and rear bearings 3, 4 by bolts 6, and supports the rotary shaft 2 by the bearings 3, 4. The broken line O is the center of rotation.

A large number of stator poles 7 are fixed radially from the housing 5, and a cylindrical yoke 8 surrounds the outside thereof to form a magnetic circuit with the stator pole 7.

FIG. 2 is a diagram showing an assembly process of the stator pole 7. A strip-shaped thin soft magnetic body 11 is wound around the stator core 10 (FIG. 2A) many times (FIG. 2B). The thinner the electromagnetic steel sheet, the lower the iron loss, and the thinner the electromagnetic steel sheet used as the soft magnetic body 11, the better. An insulating film is applied to the surface of the soft magnetic body 11. Since the stator pole 7 is produced by winding the thin soft magnetic body 11, waste of material remaining at the time of punching can be eliminated.

In addition, there are two types of electrical steel sheets: non-oriented electrical steel sheets and directional electrical steel sheets. Generally, directional electrical steel sheets are used for applications such as transformers, and non-oriented electrical steel sheets are used for applications such as rotating machines. It is done. In this embodiment, a directional electrical steel sheet having a lower magnetic loss than a non-oriented electrical steel sheet and having a high magnetic permeability is used as the soft magnetic body 11. The easy magnetization direction a of the grain-oriented electrical steel sheet is perpendicular to the length direction of the soft magnetic body 11 (the direction of winding around the core 10). When a grain-oriented steel sheet is used as the electromagnetic steel sheet used for the stator core 10, the easy magnetization direction a is perpendicular to the length direction of the soft magnetic body 11 (direction wound around the stator core 10). This is because the direction of the magnetic circuit formed by the stator pole 7 is matched.

The stator core 10 is slightly longer than the width of the soft magnetic body 11 so that the end portions 10a can be seen on both sides when the soft magnetic body 11 is wound. On the other hand, the flanges 12 and 13 having the holes 12a and 13a in which the end portions 10a are accommodated are mounted from both sides of the stator core 10 to which the soft magnetic body 11 is wound (FIG. 2C). As the flanges 12 and 13, non-oriented electrical steel sheets are used. Winding 15 is wound between flanges 12 of iron core 14 (FIG. 2D) formed in this way (FIG. 2E). In this way, the stator pole 7 is manufactured. The flanges 12 and 13 serve as one end and the other end of the magnetic circuit formed by the stator pole 7.

As will be described later, since the stator pole 7 is attached with the flange 13 to the yoke 8, the outer surface of the flange 13 is formed with the same curvature as the inner peripheral surface of the yoke 8. Further, since the outer surface of the flange 12 forms a magnetic gap with the rotor in the housing 5, the surface of the flange 12 is bent with a curvature that makes the magnetic gap uniform.

In FIG. 3, the housing 5 has a cylindrical shape, and the inner circumferential surface thereof is a circumferential surface around the rotation center O of the generator 1. And the through-hole 5b in which the flange 12 is accommodated in equiangular intervals is provided in the circumferential surface. Further, brim 5c for connecting to bearing 3 is provided at both ends, and bolt hole 5d is drilled in brim 5c. The flange 12 of the stator pole 7 is inserted into the hole 5b so that the outer surface 12a of the flange 12 is along the inner peripheral surface 5a of the housing 5 and is positioned on the radial line from the rotation center 0. It is arranged on the outer peripheral surface side of the housing 5. And the edge 5e around the hole 5b in which the inner flange 12 is inserted is welded and fixed.

FIG. 4 is a manufacturing diagram of the yoke 8. The yoke 8 is formed in a cylindrical shape by winding a strip-shaped non-oriented electrical steel sheet 17 (soft magnetic material) many times. The non-oriented electrical steel sheet 17 is covered with an insulator on the surface. The non-oriented electrical steel sheet 17 is used in order to introduce magnetic lines of force from the stator pole 7 attached to the inner peripheral surface. As a separate body from the starter pole 7, the belt 8 is wound around the non-oriented electrical steel sheet 16 to produce the yoke 8, so that waste of the material remaining at the time of punching can be eliminated.

FIG. 5 is a partial cross-sectional exploded view of the generator 1. In the figure, for the sake of easy understanding of each component, only one stator pole 7 is shown fixed to the housing 5, and the other stator poles 7 are shown removed. The rotor 16 has a cylindrical shape, and has magnetic poles 16a in which N and S poles are alternately arranged on the outer periphery. The rotor 16 is inserted into the housing 5 with a small gap (1 to 2 mm), and this gap constitutes a magnetic gap.

The bolt holes 5 d of the housing 5 and the bolt holes 2 a of the bearing 3 are fixed by bolts 6 and nuts 4. Therefore, the structural strength of the generator 1 is governed by the bearing 3 housing 5. On the other hand, the stator pole 7 and the yoke 8 only need to have strength to hold themselves. Since the outer peripheral side of the housing 5 close enough to have a magnetic gap with the rotor 16 is a structural material responsible for fixing the stator pole, the diameter of the structural material is not dominant with respect to the length of the stator pole 7. This means that, when the number of turns of the winding 15 is increased, even if the length of the stator pole 7 is increased, only the diameter of the yoke 8 is increased, and the bearing 3 and the housing 5 as structural materials are greatly changed. It means not to do.

When the generator 1 is used for wind power generation with a low rotational speed, the rotational speed is low and the period of the alternating magnetic field generated thereby is also long. Therefore, the eddy current generated in the flanges 12 and 13 does not increase, and the iron loss at this point is small. On the other hand, in the stator pole 7 and the yoke 8 that occupy most of the length of the magnetic circuit, the electromagnetic steel plates overlap with each other in an insulated state, so that the iron loss is small.

Further, when the rotor 16 rotates, the stator pole 7 receives a force that vibrates in the circumferential direction of the housing 5, and this is supported at a point where the housing 5 generates the vibration.

The yoke 8 is in contact with the outer surface of the flange 13 of the stator pole 7. Since the yoke 8 and the stator pole 7 are not structural materials, a mechanism for holding the yoke 8 against the stator pole 7 so as not to be displaced in the direction of the rotating shaft 2 is sufficient.

In the operation of the generator 1, the lines of magnetic force emitted from the rotor 16 reach the flange 12 through the magnetic gap. The lines of magnetic force reaching the flange 12 reach the flange 13 along the direction of easy magnetization of the soft magnetic body 11 and move from here to the yoke 8. Then, after reaching the other stator pole 7 again, it returns to the rotor 16.

In the above embodiment, the stator core 10 and the flanges 12 and 13 are used for the convenience of manufacturing, but these need not be used. For example, after winding the soft magnetic body 11 without a core, winding it, positioning it on the nonmagnetic housing 5 at equal angular intervals, and then applying a thick resin to the stator pole 7 and the housing 5 to harden them. good.

Further, the non-magnetic housing 5 may not have the through hole 5b. In this case, although the gap of the magnetic gap is widened, the strength of the housing 5 is enhanced.

In the present embodiment, the stator pole 7 having 12 poles is shown, but a larger number of poles may be used. On the other hand, the number of poles of the permanent magnet should be as small as possible so as to reduce cogging.

It is a perspective view of a generator. It is a figure which shows the assembly process of a stator pole. It is a figure which shows the attachment process of a stator pole. It is a creation figure of a yoke. It is a partial cross section exploded view of a generator.

DESCRIPTION OF SYMBOLS 1 Generator 2 Rotating shaft 3 Bearing 5 Housing 7 Stator pole 8 Yoke 10 Stator core 11 Soft magnetic body 16 Rotor

Claims (3)

A number of stator poles wound on an iron core wound with a belt-shaped electromagnetic steel sheet;
The stator pole is fixed to the outer peripheral surface side at equal angular intervals, and a non-magnetic housing with one end of the magnetic circuit of the stator pole facing the inner peripheral surface side,
A yoke in which the other end of the stator pole is in contact with a cylindrical inner peripheral surface wound with a belt-shaped electromagnetic steel sheet;
A rotor having magnetic poles formed by a number of permanent magnets inserted into the housing and forming a magnetic gap with one end of the magnetic circuit of the stator pole facing the inner peripheral surface of the housing;
A rotating shaft for rotating the rotor;
A generator having a bearing that supports the rotating shaft and is fixed to the housing.
The generator according to claim 1, wherein the strip-shaped electromagnetic steel plate of the stator pole is a directional magnetic steel plate, and an easy magnetization axis is made to coincide with a direction of a magnetic circuit of the stator pole.
Many stator poles with windings on the iron core,
A generator comprising: a stator pole fixed to the outer peripheral surface side at equal angular intervals; and a non-magnetic housing having one end of a magnetic circuit of the stator pole facing the inner peripheral surface side.