JP4357856B2 - Wind power generator - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to a wind power generator having a permanent magnet rotating element constituted by attaching a permanent magnet to the rotor core.
[0002]
[Prior art]
As described in Patent Document 1 below, a permanent magnet rotating electric machine for use in a generator is configured by arranging a permanent magnet on a rotor to form a magnetic pole, further generating a moving magnetic field on the armature side, and generating rotational energy. It is a synchronous rotating machine that transmits electric power to the armature side via the moving magnetic field and extracts electric power, and high operating efficiency can be obtained by its operating principle. Recently, a permanent magnet rotating machine can be operated at a variable speed by being combined with an inverter, and is applied to applications having a wide operating speed range.
[0003]
By the way, permanent magnets have been classified as rare earth sintered magnets in recent years and have been applied to various motors since the invention of neodymium magnets having high energy density and low cost. In particular, it can be said that the application to large-sized rotating machines has been extended because there is no feeling of pressure as in conventional magnets.
[0004]
In addition, sintered magnets contribute to increased motor output, but because they are sintered products or because they are hard and brittle, they cannot be formed into complex shapes, and at best they can be shaped by grinding and polishing. Since only shaping can be performed, arc shapes and flat plate shapes are widely used. Therefore, it is necessary to form the magnetic pole with the minimum amount of use without impairing the energy density.
[0005]
At present, wind power generators are mainly inductive generators, wound synchronous generators, and the like. Since wind energy has a low energy density, it is necessary to efficiently convert the energy into electric power. For this reason, wind turbines need to take in the maximum amount of wind energy, and technological developments such as pitch control to obtain high efficiency in a wide wind speed range are underway, including the optimum shape design of blades. In addition, since it is necessary for the generator to efficiently convert the rotational energy transmitted from the windmill into electric energy, it is hoped that the variable speed range will be expanded, that is, the ability and efficiency to convert power at any wind speed will be improved. It is rare.
[0006]
As a feature of the power generation method of wind power generation, power generation is started from cut-in wind speed, and the power generation output increases by the third power of the wind speed, and shifts to constant output operation at wind speeds after the rated wind speed. After the rated wind speed, even if the wind speed increases, the rotational speed of the windmill is pitch-controlled so as to maintain a constant rotational speed using the stall characteristics. This is due to the blade strength limit.
[0007]
However, the rotational speed after the actual rated wind speed is not constant due to the mechanical delay of the pitch control. That is, since the wind speed fluctuates in a short time due to changes in wind speed in seconds and minutes and changes in wind direction, the actual situation is that the pitch control cannot follow and the rotation speed pulsates greatly. According to our survey, it has become clear that fluctuations of 10% to 25% actually occur with respect to the rated speed (at the rated wind speed).
[0008]
Thus, the characteristic of the windmill is variable speed drive having a constant output range of about 20%, and combining a generator that matches this characteristic contributes to an increase in output as a wind power generation system.
[0009]
Induction generators, which are conventional wind power generators, employ a pole number conversion method and slip control to enable variable speed operation. In the case of such a system, the influence on the system such as inrush current is large, and the incidental facilities become large due to the installation of the protection circuit. In addition, a reduction in power factor is inevitable, and energy consumption is large, including the original low efficiency.
[0010]
On the other hand, the winding synchronous generator can be operated in a relatively high efficiency and wide variable speed range. However, a brush must be used to energize the rotor winding with an exciting current, which is problematic in terms of maintenance. Further, in order to generate a direct current, it is essential to provide an exciter (exciter). However, since the generation power of this excitation current is positioned as energy loss, there is a limit in terms of efficiency.
[0011]
Compared to these conventional generators, permanent magnet generators use the magnetic force of the magnet as a field in the first place, so excitation by an exciter is unnecessary and high efficiency can be realized. In addition, since no brush is required, the maintenance can be greatly improved. Further, if the permanent magnet generator can be provided with characteristics that match the output characteristics unique to the aforementioned wind power generation while maintaining this feature, high cost performance can be achieved.
[0012]
[Patent Document 1]
Japanese Patent Laid-Open No. 11-299197
[Problems to be solved by the invention]
The present invention has been made in view of the above circumstances, and an object thereof is to provide a wind power generator having high efficiency and reliability, a wide variable speed range, and desirable output characteristics for wind power generation.
[0016]
[Means for Solving the Problems]
According to a first aspect of the present invention, there is provided a wind power generator having a permanent magnet rotor that forms a rotor magnetic pole by embedding a permanent magnet in a rotor iron core to form a permanent magnet rotating electric machine , and the rotor magnetic pole per pole Two flat permanent magnets are provided opposite to each other, and a polar arc that is a ratio of an angle of the permanent magnet arrangement portion to an angle corresponding to one magnetic pole pitch of the magnet pole is in a range of 70% to 92%, The outer angle formed by the two permanent magnets is in the range of 60 ° to 90 °, and the fluctuations in the power generation end voltage and current of the wind power generator are each in the range of the rotational speed from 125 to 125% of the rated rotational speed. It is characterized by being in the range of 20%.
[0017]
According to a second aspect of the present invention, there is provided a wind power generator having a permanent magnet rotor that forms a rotor magnetic pole by embedding a permanent magnet in a rotor iron core and constitutes a permanent magnet rotating electric machine . Two flat permanent magnets are provided opposite to each other, and a polar arc that is a ratio of an angle of the permanent magnet arrangement portion to an angle corresponding to one magnetic pole pitch of the magnet pole is in a range of 85% to 92%, a two outer angle range from 60 ° to 90 ° formed of permanent magnets, on the front of the rotor core of the permanent magnet, the fan-shaped window having said permanent magnet parallel to the sides are formed, the wind power The fluctuations of the power generation end voltage and current of the machine are in the range of 20% from the rated speed to 125% of the rated speed, respectively.
[0018]
The invention described in claim 3 is characterized in that a fan-shaped hollow or solid magnetic piece is mounted on the fan-shaped window .
According to a fourth aspect of the present invention, in a wind power generator having a permanent magnet rotor that forms a rotor magnetic pole by embedding a permanent magnet in a rotor iron core to constitute a permanent magnet rotating electric machine , the rotor magnetic pole per pole Two flat permanent magnets are provided opposite to each other, and a polar arc that is a ratio of an angle of the permanent magnet arrangement portion to an angle corresponding to one magnetic pole pitch of the magnet pole is in a range of 85% to 92%, The outer angle formed by the two permanent magnets is in the range of 60 ° to 90 °, a groove is formed in the rotor core on the front surface of the permanent magnet, the gap length is increased , and the power generation end voltage of the wind power generator and The variation of the current is in the range of 20% in the range of the rotational speed from the rated rotational speed to 125% of the rated rotational speed.
[0022]
DETAILED DESCRIPTION OF THE INVENTION
A first embodiment of a permanent magnet rotor and a wind power generator according to the present invention will be described below with reference to FIGS. 1 and 2.
FIG. 1A schematically shows a cross-sectional structure of a permanent magnet rotating electric machine, and an armature 1 has a configuration in which an armature coil 1b is housed in a slot formed in an armature core 1a. In the field space, the rotor 2 in which the rotor magnetic pole 2b is formed on the rotor core 2a is disposed.
[0023]
As shown in detail in FIG. 1 (b), the rotor 2 has two flat magnets 4 per one magnetic pole 2b opposed to the magnetic pole mounting punched portion provided in the rotor core 2a. The pole arc β / α, which is the ratio of the angle β of the magnet 4 placement portion to the angle α corresponding to one magnetic pole pitch of the magnet pole , is set to 92% or more, and the angle γ formed by the magnets 4 arranged on the same magnetic pole Is in the range of 75 ° to 105 °.
[0024]
When the permanent magnet rotating electrical machine is applied as a wind power generator, it is necessary to add power generation characteristics suitable for the output characteristics of the wind turbine on the prime mover side. As a feature of the power generation system of the wind power generation system, power generation is started from the cut-in wind speed, and the power generation output increases at almost the third power of the wind speed, and shifts to a constant output operation at a wind speed after the rated wind speed. After the rated wind speed, even if the wind speed increases, the rotational speed of the windmill is pitch-controlled so as to maintain a constant rotational speed using the stall characteristics. This is due to the blade strength limit.
[0025]
Therefore, the generator should ideally be adapted to the relationship between the rotational speed and the output (hereinafter referred to as load characteristics) as shown in the load curve of FIG. In this case, as the permanent magnet rotor, a surface magnet arrangement type rotor configuration as shown in FIG. 1 is preferable because a high power factor can be obtained.
[0026]
FIG. 2A shows the output characteristics of the generator employing the rotor, with the load current as a parameter. Since the load characteristics can be covered only with the rated current, the generator output does not fluctuate, and high-quality power generation is possible.
[0027]
However, the actual rotational speed after the rated wind speed is not constant as in the load characteristic of FIG. 2A due to the mechanical delay of the pitch control. In other words, since the wind speed fluctuates in a short time due to changes in the wind speed in seconds and minutes, or changes in the wind direction, the actual situation is that the pitch control cannot follow and the rotation speed pulsates greatly.
[0028]
According to our survey, it has become clear that fluctuations of 10% to 25% actually occur with respect to the rated speed (at the rated wind speed). Similar to FIG. 2A, when viewed as the output vs. rotation speed, the relationship as shown in FIG. 2B is obtained. This makes the fluctuation range 20% of the rated rotational speed.
[0029]
Covering such load characteristics with a constant current is impossible with the generator characteristics. Even when 120% current flows, the load cannot be covered. For example, if it can be covered with 130% current, it leads to a power factor reduction of 20% or more, and output fluctuation becomes large, so that high-quality power cannot be supplied.
[0030]
Even if it is considered to stabilize output fluctuations with a power electronics device installed in the latter stage, the fluctuation range of the current and voltage at the power generation end is limited to 120% or less, and fluctuations exceeding that limit occur. On the other hand, it is necessary to install a power storage device such as a battery or a flywheel device, and the power generation system itself becomes large. In particular, the wind power generation system is often not cost effective. Thus, the characteristic of the windmill is variable speed drive having a constant output range of about 20%, and combining a generator that matches this characteristic contributes to an increase in output as a wind power generation system.
[0031]
The permanent magnet rotor of the present embodiment has almost no gap between the magnets 4 of the adjacent magnetic poles 2b (polar arc of 93% or more). Therefore, when the angle γ exceeds the above range, the output characteristics are almost not shown. It becomes the same as that of 2 (a). However, when γ falls within the above range, a space through which a reluctance magnetic flux having an effect of stabilizing the output in addition to the magnetic flux of the magnet 4 flows is secured in the iron core portion of the front surface of the magnet 4.
[0032]
As a result, the permanent magnet rotor of the present embodiment achieves high output by the magnet magnetic flux, and the function of maintaining high output is added by the reluctance magnetic flux. Therefore, from the cut-in wind speed to the rated wind speed (rotation speed), it is possible to convert the output of the windmill into electrical energy without leaving a surplus, and even in the rotational speed fluctuation that occurs between the rated wind speed and the cut-out wind speed, The fluctuation of the load current can be suppressed within an allowable range of the electronic device, and as a result, a constant output can be obtained.
[0033]
In addition, the wind power generator of the present embodiment can keep the fluctuations in the power generation end voltage and the load current within 20% so that the fluctuations can be absorbed by the stabilizing action of the power electronics device in the subsequent stage. An inexpensive wind system can be provided without installing any incidental facilities.
[0034]
Next, a second embodiment of the present invention will be described. As shown in FIG. 3, the permanent magnet rotor of the present embodiment is configured so that two flat magnets 4 per one pole 2b are opposed to the magnet mounting punched portion provided in the rotor core 2a. It is inserted, and the pole arc β / α of the magnet pole is in the range of 70% to 92%, and the angle γ formed by the magnet 4 arranged on the same magnetic pole is in the range of 60 ° to 90 °. ing.
[0035]
When the polar arc β / α is in the above range, the reluctance magnetic flux passes through the iron core existing between the magnets of the adjacent magnetic poles, and a space through which the magnetic flux flows after the magnet 4 is secured. However, when the angle γ exceeds this angular range, the amount of reluctance magnetic flux is greatly reduced, and the amount of magnetic flux is also reduced thereby, so that high output by the magnet is hindered. As a result, although the function of maintaining the output is incidental, in order to exhibit the rated output, the shortage of the magnet magnetic flux is covered by increasing the current, and the overall power factor is reduced. When the angle γ is set within the above range, the amount of reluctance magnetic flux increases, and a magnetic flux sufficient to prevent the power factor from decreasing can be obtained.
[0036]
Therefore, from the cut-in wind speed to the rated wind speed (rotation speed), it is possible to convert the output of the windmill into electrical energy without leaving a surplus, and even in the rotational speed fluctuation that occurs between the rated wind speed and the cut-out wind speed, The fluctuation of the load current can be suppressed within an allowable range of the electronic device, and as a result, a constant output can be obtained.
[0037]
Next, a third embodiment of the present invention will be described. As shown in FIG. 4, the permanent magnet rotor of the present embodiment has a magnet pole 4 having a relatively high polar arc range of 85% to 92%. The fan-shaped window 3 having sides parallel to the magnet is formed on the front surface.
[0038]
Depending on the dimensional specifications of the generator, the magnetic flux may be insufficient. In this case, when the amount of magnetic flux is increased, the magnet length increases, the interval between adjacent magnetic poles becomes narrow, the space where the reluctance magnetic flux flows becomes insufficient, and the output maintaining function is lowered.
[0039]
In that case, when the fan-shaped window 3 is formed on the front surface of the magnet 4 with a cross-sectional area that does not inhibit the flow of magnetic flux of the magnet 4, that is, the iron core 2a is not magnetically saturated, the reluctance magnetic flux can be increased. . That is, by interrupting the magnetic circuit of the magnet 4 in the direction of the center of the magnetic pole, the reluctance magnetic flux leaking there can be guided to a desired flow path that passes behind the magnet 4, resulting in the reluctance magnetic flux. Can be supplemented.
[0040]
Therefore, from the cut-in wind speed to the rated wind speed (rotation speed), it is possible to convert the output of the windmill into electrical energy without leaving a surplus, and even in the rotational speed fluctuation that occurs between the rated wind speed and the cut-out wind speed, The fluctuation of the load current can be suppressed within an allowable range of the electronic device, and as a result, a constant output can be obtained.
[0041]
Next, as shown in FIG. 5, the permanent magnet rotor of the fourth embodiment of the present invention has a configuration in which a fan-shaped hollow or solid-shaped magnetic piece 5 is mounted on a fan-shaped window widened in advance. is there.
[0042]
According to the present embodiment, the balance between the magnetic flux and the reluctance magnetic flux is increased, for example, when the rotational speed fluctuation range at a wind speed higher than the rated wind speed is increased or when it is necessary to match the load characteristic specifications of different wind turbines. When the result is broken, as a result, it becomes impossible to keep the output constant.By changing the size of the window to the required size, the balance is restored and the fluctuation of the load current is within the allowable range of the power electronics device. Can be suppressed. Moreover, since the characteristics of the generator can be easily matched to the wind turbine output, the generator can be made into a common part, and the production cost can be reduced.
[0043]
Next, as shown in FIG. 6, the permanent magnet rotor according to the fifth embodiment of the present invention has a fan-shaped window, although the polar arc β / α of the magnet pole is limited to the range of 85% to 92%. Instead of this, a groove having a depth t is formed on the surface of the rotor core 2a facing the front surface of the magnet 4, and the gap length is widened only at that portion.
[0044]
As the groove depth t increases, the effect of increasing the reluctance magnetic flux increases. However, since the gap length increases conversely, the magnetic flux decreases, and cannot be deepened unnecessarily. In our investigation, it has been obtained that the size of t is preferably in the range of 10% to 30% with respect to the normal gap length.
[0045]
Next, as shown in FIG. 7, the permanent magnet rotor according to the sixth embodiment of the present invention inserts an arc-shaped magnet 4a into a magnet mounting punched portion provided in the rotor core 2a, and In this configuration, the polar arc β / α of the magnet pole is in the range of 65% to 80%.
[0046]
In this embodiment, there is no space for the reluctance magnetic flux to flow on the front surface of the magnet 4a, and only the magnetic circuit that flows from between the magnets of adjacent magnetic poles to the back of the magnet serves as the flow path. Therefore, the interval between the magnets needs to be relatively wide, and the above range is set. The arcuate magnet 4a has a shape along the outer periphery of the rotor. For example, the magnet 4a may be arranged in a reverse arcuate state.
[0047]
According to the permanent magnet rotor of this embodiment, it is possible to convert the output of the windmill from the cut-in wind speed to the rated wind speed (number of rotations) without leaving a surplus, and further, from the rated wind speed to the cut-out wind speed. Even in the rotational speed fluctuation that occurs in the meantime, the fluctuation of the load current can be suppressed within an allowable range of the power electronics device, and as a result, a constant output can be obtained.
[0048]
The arc-shaped magnet 4a can be a single magnet, but the sector angle is made smaller than the punched hole of the iron core 2a, and the fourth magnet is formed in the gap formed in the punched hole. By arranging the magnetic pieces as in the embodiment, the reluctance magnetic flux passage, and thus the ratio of the reluctance magnetic flux amount and the magnet magnetic flux amount can be arbitrarily and easily adjusted.
[0049]
This breaks the balance between the magnetic flux and the reluctance flux, such as when the rotational speed fluctuation range at a wind speed higher than the rated wind speed becomes large, or when it is necessary to match the load characteristic specifications of different wind turbines, When it becomes impossible to maintain a constant output, the amount of magnetic flux and reluctance magnetic flux flow path can be changed arbitrarily to restore the balance and suppress fluctuations in the load current within the allowable range of the power electronics device. . Moreover, since the characteristics of the generator can be easily matched to the wind turbine output, the generator can be made into a common part, and the production cost can be reduced.
[0050]
Next, as shown in FIG. 8, the permanent magnet rotor according to the seventh embodiment of the present invention uses a kamaboko-shaped magnet 4b as a permanent magnet. The designation of the polar arc β / α is the same as that in the sixth embodiment. The effect of the magnet-shaped magnet 4b is basically the same as that of the arc magnet, but further, the reluctance magnetic flux is increased and an excellent output maintaining capability is obtained.
[0051]
The reluctance magnetic flux can be increased by securing the flow path, but as described above, it can also be increased by eliminating leakage in the direction of the magnet. The magnet-shaped magnet 4b has a thick magnet at the center of the pole. However, since the magnet functions to inhibit the flow of reluctance magnetic flux, the effect at the center of the pole is great. Furthermore, since the leakage flux of the reluctance magnetic flux tends to increase at the pole center, the leakage of the reluctance magnetic flux can be blocked strongly and effectively by the effect of the magnet-shaped magnet 4b. As a result, the output maintaining capability of the permanent magnet rotating electric machine can be improved with a small amount of magnetic flux, and the power factor and efficiency can be improved.
[0052]
Next, an eighth embodiment of the present invention will be described. In the permanent magnet rotor of this embodiment, as shown in FIG. 9, an iron core (annular part) disposed on the outer surface of the arc-shaped magnet 4a is formed by an annular magnetic body 6 separate from the iron core 2a. The annular magnetic body 6 is fixed by using an iron core portion formed between adjacent magnets 4a as a joint.
[0053]
By making this annular portion a member different from the iron core 2a, the shape or material of this portion can be arbitrarily selected. For example, in the case where it is difficult to prevent scattering due to the centrifugal force of the magnet 4a when the maximum rotational speed is increased, the configuration of FIG. 7 can only be dealt with by increasing the thickness of the annular portion. Inevitably, the position of the magnet 4a moves to the inner peripheral side, so the amount of magnetic flux decreases, and the leakage component flowing through the annular portion of the magnet magnetic flux increases, so that the amount of magnet magnetic flux contributing to the output is reduced. It will decline.
[0054]
In the present embodiment, in that case, the wall thickness can be reduced by using a high-strength material such as marage steel for the annular portion material, and as a result, a reduction in output can be prevented. Further, the configuration of FIG. 7 can be easily adopted by simply deleting the annular portion.
[0055]
Furthermore, by making the shape of the annular portion a convex arc shape, the magnetic flux distribution flowing in the gap can be shaped into a sine wave shape, and thereby the harmonic magnetic flux component can be reduced. Thereby, the harmonic loss caused by the harmonic magnetic flux component can be reduced, and the efficiency can be improved. Thus, according to the present embodiment, the generator performance can be easily adapted to various wind turbine characteristics or load specifications.
[0056]
Next, a ninth embodiment of the present invention will be described. As shown in FIG. 10, the permanent magnet rotor of this embodiment is the same as the permanent magnet rotor of the eighth embodiment, except that the cooling fins 7 are attached to the joint portions of the annular magnetic body 6 in the axial direction. It is a thing. Since the annular part of the iron core 2a can be made into an arbitrary shape using another material, the ring part is extended in the axial direction to form the fins 7. In the figure, an axial fin is formed, but only the portion of the fin 7 can be made nonmagnetic.
[0057]
There are several effects of the fin 7. One of them is an action of quickly radiating heat from the fin 7 due to surface loss or the like generated in the permanent magnet 4 a and the annular magnetic body 6. Another effect is that the cooling air generated by the rotation of the fins 7 circulates and cools the end portion of the armature coil 1b that tends to have a relatively high temperature.
[0058]
Generally, a wind power generator is housed in a nacelle, but the nacelle often adopts a hermetically sealed structure for protection of other electrical components. Moreover, natural cooling is generally used for cooling the generator, and since the cooling conditions are poor, the generator tends to be manufactured in a relatively large size. In the present embodiment, since the armature coil end portion, which is a hot spot, can be cooled by the fins 7, the cooling performance is dramatically improved, and the generator itself can be downsized. As a result, the generator weight, physique, and loss are reduced, and the output can be improved and the nacelle size can be reduced.
[0059]
【The invention's effect】
According to the present invention, it is possible to provide a wind power generator having high efficiency and reliability, a wide variable speed range, and output characteristics desirable for wind power generation.
[Brief description of the drawings]
1A and 1B show a first embodiment of the present invention, in which FIG. 1A is a radial sectional view schematically showing a permanent magnet rotating electrical machine including a permanent magnet rotor according to the present embodiment, and FIG. The fragmentary sectional view which shows the said permanent magnet rotor.
FIG. 2 is a curve diagram for explaining the operation (b) of the permanent magnet rotor according to the first embodiment of the present invention in comparison with the operation (a) of a conventional permanent magnet rotor.
FIG. 3 is a partial cross-sectional view of a permanent magnet rotor according to a second embodiment of the present invention.
FIG. 4 is a partial cross-sectional view of a permanent magnet rotor according to a third embodiment of the present invention.
FIG. 5 is a partial cross-sectional view of a permanent magnet rotor according to a fourth embodiment of the present invention.
FIG. 6 is a partial sectional view of a permanent magnet rotor according to a fifth embodiment of the present invention.
FIG. 7 is a partial sectional view of a permanent magnet rotor according to a sixth embodiment of the present invention.
FIG. 8 is a partial sectional view of a permanent magnet rotor according to a seventh embodiment of the present invention.
FIG. 9 is a partial cross-sectional view of a permanent magnet rotor according to an eighth embodiment of the present invention.
FIG. 10 is an axial sectional view of a wind power generator provided with a permanent magnet rotor according to a ninth embodiment of the present invention.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 ... Armature, 1a ... Armature core, 1b ... Armature coil, 2 ... Rotor, 2a ... Rotor core, 2b ... Rotor magnetic pole, 3 ... Window, 4, 4a, 4b ... Magnet, 5 ... Magnetic piece , 6 ... annular magnetic body, 7 ... fin, 8 ... shaft.

Claims (4)

In a wind power generator having a permanent magnet rotor that embeds a permanent magnet in a rotor core to form a rotor magnetic pole and constitutes a permanent magnet rotating electrical machine ,
Two flat permanent magnets are provided to face each rotor magnetic pole, and the polar arc, which is the ratio of the angle of the permanent magnet arrangement portion to the angle corresponding to one magnetic pole pitch of the magnet pole, ranges from 70% to 92%. %, The outer angle formed by the two permanent magnets is in the range of 60 ° to 90 °, and the variation in the power generation end voltage and current of the wind power generator is from the rated speed to 125 of the rated speed. A wind power generator characterized by being in the range of 20% in each of the rotation speed ranges of%. In a wind power generator having a permanent magnet rotor that embeds a permanent magnet in a rotor core to form a rotor magnetic pole and constitutes a permanent magnet rotating electrical machine ,
Two flat permanent magnets are provided facing each rotor magnetic pole, and the polar arc, which is the ratio of the angle of the permanent magnet arrangement portion to the angle corresponding to one magnetic pole pitch of the magnet pole, is 85% to 92%. % by weight, the a two outer angle range from 60 ° to 90 ° formed of permanent magnets, on the front of the rotor core of the permanent magnet, the fan-shaped window having said permanent magnet parallel to the sides The wind power generator is characterized in that fluctuations in the power generation end voltage and current of the wind power generator are within 20% in a range of the rotational speed from the rated speed to 125% of the rated speed. 3. The wind power generator according to claim 2, wherein a fan-shaped hollow or solid magnetic piece is mounted on the fan-shaped window. In a wind power generator having a permanent magnet rotor that embeds a permanent magnet in a rotor core to form a rotor magnetic pole and constitutes a permanent magnet rotating electrical machine ,
Two flat permanent magnets are provided facing each rotor magnetic pole, and the polar arc, which is the ratio of the angle of the permanent magnet arrangement portion to the angle corresponding to one magnetic pole pitch of the magnet pole, is 85% to 92%. % by weight, the a two outer angle range from 60 ° to 90 ° formed of a permanent magnet, said forming grooves on the front surface of the rotor core of the permanent magnet, to increase the gap length, the wind A wind power generator characterized in that fluctuations in the power generation end voltage and current of the generator are within a range of 20% from a rated speed to a speed of 125% of the rated speed, respectively.

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