JP2021050727A - Propeller-type wind power generator - Google Patents

Abstract

To provide a propeller-type wind power generator which can maintain rotation even at a strong wind, can increase a power generation total amount, and is favorable in efficiency even at a weak wind while solving a problem that, in a small-sized wind power generator, safety has been secured by applying a brake at the strong wind, thus causing the lowering of a power generation capacity at the strong wind.SOLUTION: A propeller-type wind power generator has a driven member which rotates while being connected to a generator shaft, and a drive member which rotates while being connected to a propeller 1. The driven member and the drive member are connected to each other via a spiral spring 24, an angle between the drive member and the driven member is displaced by torque which is received by the propeller by a wind while withstanding a resilient force of the spiral spring, a pitch of the propeller is changed according to the displacement of the angle, and breakage can be thereby prevented.SELECTED DRAWING: Figure 9

Description

The present invention relates to a propeller-type wind power generator used for a micro wind turbine or a small wind turbine, and provides a propeller-type wind power generator that enables power generation in a wide range of wind speeds and enhances the safety and power generation efficiency of the wind turbine. Is. The Agency for Natural Resources and Energy defines a wind power generator of less than 20 Kw / h as a small wind power generator, and this definition will be used in the following description. In addition, a wind power generator larger than this is referred to as a large wind power generator.

Conventionally, micro wind power generators and small wind power generators used for wind power generators with an output of several hundred w / h to about 20 Kw / h are designed by the rotation speed of the rotor when the wind speed becomes faster than a predetermined value. I tried to apply the brakes so that the value would not be exceeded. Since there is a margin in cost for large wind power generators, the angle (elevation angle) of the rotor blades is changed by using flood control etc. according to the wind speed, but for small ones there is a margin in cost. The cheapest brake is used.

In this way, when the pitch of the propeller is fixed and the brake is applied when the wind speed is equal to or higher than a predetermined value, the power is designed to be efficiently generated at a wind speed of 5 m / sec, for example, when the wind speed is high to some extent. Then, since the angle of the blade is constant regardless of whether the wind speed is slow or fast, the efficiency becomes poor at a wind speed other than the optimum wind speed. Especially when the wind speed is slow, the energy efficiency becomes extremely poor because the brakes are applied even though the wind energy is sufficient. From this point of view, a device that changes the effective diameter of the propeller according to the wind speed has been developed as shown in Patent Document 1.

In addition, in the case of a fixed-pitch wind power generator, it is designed to generate electricity efficiently when the wind speed is high to some extent. Then, since the angle of the blade is constant regardless of whether the wind speed is low or high, the efficiency becomes extremely poor especially when the wind speed is high as described above. From this point of view, a propeller pitch that changes according to the wind speed has been developed.
As an example of such a thing, in the one disclosed in Patent Document 2, the rolling column moves in the slide rail according to the rotation speed of the propeller, whereby the pushing member and the pressing member move, and the pitch of the propeller is adjusted. I try to change it. Therefore, even if the wind speed increases, the rotation speed of the blades does not rise to a dangerous area, and it is not necessary to apply the brake.

Therefore, even when the wind speed is high, the blades rotate at a rotation speed at which effective power generation is possible without applying the brakes, so that power can be generated efficiently even in strong winds. However, the one described in Patent Document 1 has a large number of parts and a complicated structure. In other words, in order to be able to install it on existing propeller-type wind power generators whose pitch cannot be changed, the structure needs to be simple and lightweight. In other words, if the weight of the existing propeller-type wind power generator increases, the strength of the columns may be insufficient, and the weight increase should be avoided as much as possible. Further, the plurality of rolling columns that move in the slide rail move independently of each other, and if the positions of the respective rolling columns deviate from each other, there is a problem that the balance is lost and vibration occurs. ..

Japanese Patent Application Laid-Open No. 2003-65205 JP-A-2010-127278

The present invention relates to a propeller type wind power generator, and it is as simple as possible to change the pitch angle of the propeller according to the power generation load, that is, the torque of the generator, and efficiently convert the energy of the wind into electric power. It needs to be realized by the structure. That is, it is preferable to set the pitch angle to be the most efficient according to the power generation load, and in order to effectively obtain the energy of the wind, it is necessary to effectively obtain the energy of the wind even if the pitch is changed according to the rotation speed. Can't.

In addition, a rotation control mechanism that changes the pitch of the propeller with a motor is incorporated to prevent the rotation speed of the propeller from exceeding the safe range in strong winds, but in a small wind power generator, such means is not available from the viewpoint of cost and space. Have difficulty. For this reason, in a small wind power generator that uses a fixed-pitch propeller that does not have a rotation control mechanism, the output of the generator is shorted to prevent over-rotation, and an electric brake that uses the electrical braking force applied to the generator. Prevents the rotor from over-rotating. However, sometimes the driving force of the propeller exceeds this braking force, resulting in an over-rotation state. The electric brake short-circuits the output of the generator, and if it becomes over-rotated, there remains a risk that the coil of the generator will burn out.

Since such a small wind power generator does not have sufficient braking as described above, it has been designed at a pitch so that an accident does not occur even in a strong wind at the expense of performance at a low wind speed. Therefore, the power generation efficiency is about half that of a large wind power generator having a variable pitch mechanism. As described above, since there is a large difference in the power generation rate, in the present invention, by using a small and simple mechanism, the wind speed capable of generating power can be expanded to the same level as that of a large wind power generator, and the amount of power generation can be significantly increased. , Prevent over-rotation and improve the safety of the wind turbine. For this reason, it is necessary to change the pitch angle of the propeller with the simplest possible structure, and it is possible to make it smaller and lighter, which makes it possible to replace the hub part of the existing small wind power generator. You can also do it.

The present invention has a propeller mounting portion that rotates within a certain angle with respect to a power generation shaft interlocking with a generator, a plurality of propellers are mounted on the propeller mounting portion, and the plurality of propellers rotate in a direction perpendicular to the rotating surface. The propeller is mounted so that the pitch of the propeller is variable, and the propeller mounting part rotates with respect to the power generation shaft according to the torque generated by the propeller due to the force of the wind, and the pitch of the propeller is changed by this rotational movement. Is. As a result, the torque generated by the propeller is small when the wind is weak, and the pitch does not change much from the initial state.

Then, since the torque increases in a strong wind, the pitch changes significantly from the initial state. In addition, when the wind becomes extremely strong like a typhoon, the torque is large and the pitch changes to the limit. In this state, the propeller rotates at a high speed. Here, the output of the generator can be short-circuited to apply dynamic braking. In this case, since the pitch has changed to the limit, the torque does not rise to an unexpected state, and the generator does not burn out due to dynamic braking.

In the propeller type wind power generator of the present invention, the pitch of the propeller is changed according to the torque received by the propeller, that is, the torque that the propeller drives the generator. Therefore, the torque received by the propeller is small in weak winds, and if the pitch is set to be the most efficient at that wind speed, power can be generated efficiently even in weak winds.

In strong winds, the force that the propeller receives from the wind destroys the propeller because the propeller receives more driving force than expected due to the wind, and the propeller blades bend or receive strong vibrations. Centrifugal force is the force received by increasing the number of revolutions of the propeller in strong winds. In strong winds, the force to bend the blades and the vibration caused by the vortex are applied. It is not easy to endure these. Therefore, by changing the pitch of the propeller according to the driving force received by the propeller in a strong wind, the force on the propeller due to the wind can be weakened, and the propeller can be prevented from being damaged.

Further, the driving force received by the propeller, that is, the torque is small in a weak wind. In this case, by optimally setting the pitch of the propeller to the wind speed, it is possible to generate electricity efficiently even in a weak wind. When the wind becomes strong and there is a risk of damage to the propeller, the driving force received by the propeller is large, and damage can be prevented by making the pitch parallel to the wind.

In the present invention, the driven member connected to the generator and the drive member connected to the propeller are connected via an elastic body such as a spring, and the driven member and the drive member are displaced according to the torque received by the propeller by the wind. , This changes the pitch of the propeller. In other words, it has a simple configuration without using a motor or the like as a means of changing the pitch of the propeller. Therefore, even a small wind power generator, which cannot be costly, can change the pitch of the propeller between a weak wind and a strong wind. Therefore, power can be generated with maximum efficiency in weak winds, and power can be generated without braking in strong winds, so that overall power generation efficiency can be increased.

In this way, since power generation can be efficiently performed in both weak and strong winds with a simple structure, even a small wind power generator with strict cost requirements can achieve power generation efficiency comparable to that of a large wind power generator. Further, since a driving means such as a motor or an electric pressure is not used to rotate the propeller, a means for transmitting a driving force from the outside to the rotating body is unnecessary. Therefore, it is possible to install an over-rotation prevention means in place of the hub to which the propeller of the propeller-type wind power generator that has already been installed is attached. In addition, both a propeller-type wind power generator having such an over-rotation prevention means and a propeller-type wind power generator not having such an over-rotation prevention means can be composed of almost common parts, and are sold at the request of the market. be able to.

It is a perspective view of the propeller type wind power generator of this invention. It is a side sectional view of the hub of the propeller type wind power generator of this invention. It is a top view of the lever which is a part of the propeller type wind power generator of this invention. It is a front view of the hub of the propeller type wind power generator of this invention. It is a figure which shows the relationship between the wind strength of the propeller type wind power generator of this invention, and the pitch of a propeller. It is a top view which shows the other Example (Example 2) of the lever of the propeller type wind power generator of this invention. It is a perspective view which shows another Example (Example 3) of the mechanism which rotates the propeller shaft of the propeller type wind power generator of this invention. It is a perspective view which shows another Example (Example 3) of the mechanism which rotates the propeller shaft of the propeller type wind power generator of this invention. It is sectional drawing of the hub of Example 4 of the propeller type wind power generator of this invention.

Reference numerals 1 and 2 are propellers, which are attached to hubs 3, respectively. The hub 3 is connected to the shaft 5 of the generator 4 (see FIG. 2) by a nut. Propellers 1 and 2 are attached to the hub 3. The details of the hub 3 will be described below. In the following explanation, the members integrated with the propellers 1 and 2 and the propellers 1 and 2 that receive the driving force by the wind are referred to as the driving side, and the members integrated with the shaft 5 of the generator 4 are driven. Expressed as the side.

A pin support 6 is fixed to the shaft 5 so as to rotate integrally with the shaft 5. That is, a boss 8 that is inserted into the shaft 5 and is stopped from rotating with the shaft 5 by a key is provided, and a U-shaped pin support 6 is connected to the boss 8 by welding or the like. The propeller support 7 has a disk shape and is provided with a pair of propeller bearings 9 and 10. The propeller support 7 has an opening at the center, and the boss 8 is inserted into the opening. The propeller support 7 is coaxial with the shaft 5 and can freely rotate with respect to the boss 8. A retaining nut 11 is provided so that the propeller support 7 does not come off from the boss 8.

The propeller bearings 7 and 8 pivotally support the propeller shafts 12 and 13 of the propellers 1 and 2 so that the pitches of the propellers 1 and 2 can be rotated in the changing direction. That is, the propellers 1 and 2 are attached so as to be rotatable in the pitch direction via the propeller support 7 fixed to the shaft 5 of the generator 4. Curved levers 14 and 15 are fixed to the propeller shafts 12 and 13 of the propellers 1 and 2, respectively. As shown in FIG. 3, the levers 14 and 15 are provided with grooves 16, 17, 18, and 19. Here, since the levers 14 and 15 have exactly the same shape, only the lever 14 will be described. Further, a pair of pins 20, 21, 22, 23 are erected at both ends of the pin support 6.

A pin 20 is inserted into the groove 16 of the lever 14, and a pin 22 is inserted into the groove 18. When the pin 20 moves upward in FIG. 3 and the lever 14 rotates counterclockwise, the pin 20 moves in the groove 16 toward the end. At this time, the pin 22 also moves upward in FIG. 3, and the pin 22 separates from the groove 18. As a result, the pitch of the propeller interlocking with the lever 14 changes in the counterclockwise direction.

Contrary to the above description, when the pin 20 and the pin 22 move downward in FIG. 3, the pin 22 moves in the groove 18 toward the end, the pin 20 separates from the groove 16, and the lever 14 rotates clockwise. Rotate to. As a result, the pitch of the propeller interlocking with the lever 14 changes clockwise. In this way, the pins 20 and 22 and the pins 21 and 23 are alternately inserted and removed from the grooves 16 and 17 and the grooves 18 and 19, so that the angle δ at which the pitch changes can be increased. Further, by providing a difference in length between the grooves 20 and 21 and the grooves 18 and 19, the right rotation amount and the left rotation amount of the pitch can be changed with respect to the center position.

Reference numeral 24 denotes a spiral spring, one end of which is fixed to the boss 8 integrated with the shaft 5, and the other end of which is fixed to the hub 3. The hub 3 is rotatable with respect to the shaft 5, and the spiral spring 24 applies rotational elasticity to the hub 3 in the clockwise direction when viewed from the front surface (windward side) of the hub 3. Further, in order to limit the rotation range of the hub 3 with respect to the shaft 5, the hub 3 is provided with an arcuate groove 27. A stopper rod 26 projecting from the pin support 6 is inserted into the groove 27. That is, the swirl spring 24 causes the hub 3 to be in the state shown in FIG. 4 in a steady state, and when a torque resisting the elastic force of the swirl spring 24 is applied to the hub 3, the hub 3 rotates relatively counterclockwise. Although only one groove 25 is drawn in FIG. 4, another groove 25 may be provided at a position point-symmetrical to the groove 25 if necessary.

Due to the relative rotation of the hub 3 and the pin support 6, the levers 14 and 15 are rotated, whereby the propeller bearings 7 and 8 are rotated, and the pitches of the propellers 1 and 2 are rotated in the changing direction. In the embodiment shown in FIG. 3, the pins 20 and 21 are inserted into the grooves 16 and 17, and the pins 22 and 23 are inserted into the grooves 18 and 19. Then, when the pins 20 to 23 move upward in FIG. 3, the pins 22 and 23 move away from the grooves 18 and 19, the pins 20 and 21 move in the grooves 16 and 17, and the levers 14 and 15 counterclockwise. Rotate. On the contrary, when the pins 20 to 23 move downward in FIG. 3, the pins 20 and 21 leave the grooves 16 and 17, the pins 22 and 23 move in the grooves 18 and 19, and the levers 14 and 15 rotate clockwise. Rotate. By adopting a structure in which the pins and the grooves are engaged with or separated from each other in this way, the rotation angles of the levers 14 and 15 can be increased.

Here, FIG. 5 shows the relationship between the wind strength and the pitch angle. The direction of the wind is flowing from left to right in FIG. FIG. 5D shows a time when there is no wind or the wind is weak in the activated state. That is, the angles at which the propellers 1 and 2 are most likely to generate torque. FIG. 5C is a steady state, in which the wind speed is about 3 to 5 m / sec. FIG. 5B shows a rivers state at a strong wind with a wind speed of about 6 to 13 m / sec, and the operation is performed while letting the wind escape to avoid entering a burst state. In this wind region, the conventional fixed-pitch generator could not stop the operation to generate electricity, but the wind power generator of the present invention can maintain the power generation. FIG. 5A shows a feathering state during an extremely strong wind such as a typhoon, and the wind is completely released to prevent damage to the propellers 1 and 2. Although the spiral spring 14 is shown in this example, a torsion coil spring may be used in addition to the spiral spring 14.

The propeller-type wind power generator of the present invention according to the first embodiment has the above-mentioned structure, and its operation will be described below. When the wind speed is equal to or less than a predetermined value, the pitch angle is set so as to maximize the power generation efficiency. When the wind speed is equal to or higher than the predetermined value, the amount of power generation is secured while preventing damage to the propellers 1 and 2 by partially flowing the wind. Then, when the wind is strong such that the propellers 1 and 2 are damaged, the wind is completely blown to prevent the propellers 1 and 2 from being damaged without applying the brake. In this way, it is possible to generate electricity at a wide range of wind speeds while preventing damage to the propellers 1 and 2, and the amount of power generation up to a predetermined wind speed (13 m / s in this example) is maximized.

In Example 1 above, an example in which a plate body is used as the levers 14 and 15 has been shown, but as shown in FIG. 6, it can be made by processing a wire rod such as a piano wire.

In the above-mentioned first embodiment, the levers 14 and 15 and the pins 20, 21, 22, and 23 that engage with each other are shown, but as shown in FIGS. 7 and 8, the propeller shafts 12 and 13 of the propellers 1 and 2 are shown. Pinion gears 27 and 28 are provided at each end, rack gears 29 and 30 are provided at both ends of the pin support 6, and a pair of rack gears 29 and 30 are provided on the propeller support 7. When the rotation angle between the pin support 6 and the propeller support 7 deviates, the pinion gears 27 and 28 engaged with the rack gears 29, 30, 31 and 32 rotate, and the pitch angles of the propellers 1 and 2 change. Let me. In this embodiment, the pitch angle can be changed significantly.

FIG. 9 shows Example 4. The structure of the fourth embodiment is more complicated than that of the first and second embodiments described above, but the operation is stable. Those of the fourth embodiment are basically the same as those of the first and second embodiments, and the same components are given the same numbers. That is, the pin support 33 is provided in addition to the pin support 6. The pin support 33 is integrally coupled to the shaft 5 with the pin support 6. Further, a propeller support 34 is provided in addition to the propeller support 7. The propeller support 34 is coupled to the propeller support 7, is rotatable with the shaft 5, and is repressed in the rotational direction by the spiral spring 24.

In the case of the fourth embodiment, when the propellers 1 and 2 generate torque by wind pressure, the rotation angles of the shaft 5 and the propeller supports 7 and 34 deviate from each other against the elasticity of the spiral spring 24. Then, as in the first and second embodiments, the pins 20, 21, 22, and 23 rotate the levers 14, 15 by engaging with and disengaging from the grooves 16, 17, 18, and 19 of the levers 14, 15. And change the pitch of propellers 1 and 2. In the fourth embodiment, the propeller bearings 9 and 10 are supported by a pair of members, and the pins 20 and 21 and the pins 22 and 23 are supported by independent members, so that the propeller bearings 9 and 10 are stable.

In all the above embodiments, the predetermined value for controlling the rotation speed of the propellers 1 and 2 can be set by selecting the spring constant of the spiral spring 14, and can be easily set according to the strength of the propellers 1 and 2. Can be set. The pitch angle of the propellers 1 and 2 is determined by the deviation of the rotation angle between the propeller supports 7 and 34 and the pin supports 6 and 23, and the propellers 1 and 2 always have the same pitch angle.

According to the present invention, it is possible to prevent the rotation speeds of the propellers 1 and 2 from entering a dangerous region in a strong wind without relying on a brake, so that power generation can be maintained even in a strong wind, and maximum in a weak wind. Since power can be generated with the efficiency of the above, it is possible to improve the safety of small wind power generation and increase the amount of power generation. In addition, since the configuration for this purpose is achieved only by the hub 3 and is extremely simple and compact, it can be applied to a propeller type wind power generator already on the market and installed.

1,2 Propeller 3 Hub 4 Generator 5 Shaft 6,33 Pin Support 7,34 Propeller Support 8 Boss 9,10 Propeller Bearing 11 Nut 12,13 Propeller Shaft 14,15 Lever 16,17,18,19 Groove 20 , 21, 22, 23 Pin 24 Swirling spring 25, 27 Groove 26 Stopper rod 28, 35 Pinion gear 29, 30, 31, 32 Rack gear 34 Propeller support

Claims (4)

It has a driven member that rotates in connection with a generator shaft and a driving member that rotates in connection with a propeller. The driven member and the driving member are connected via an elastic body, and the propeller is connected by wind. A propeller-type wind power generator in which the angle between the driving member and the driven member is displaced by the torque received against the elastic force of the elastic body, and the pitch of the propeller is changed according to the deviation of the angle. .. A propeller support that rotatably supports the propeller in the pitch direction is provided as a driving member, a pin support is provided as a driven member, a spring that applies an elastic force in the rotational direction is provided between the respective supports, and the pin support is provided. A pin is erected on the propeller, a lever fixed to the propeller and having a groove is provided, the pin is inserted into the groove of the lever, and the lever rotates due to a deviation in the rotation direction between the propeller support and the pin support. The propeller-type wind power generator according to claim 1, wherein the pitch of the propeller is changed. A propeller support that rotatably supports the propeller in the pitch direction is provided as a drive member, a pinion gear is provided on the shaft of the propeller, a rack gear is provided on the propeller support, and a pin support is provided as a driven member. A rack gear is provided on the pin support, a spring that applies an elastic force in the rotational direction is provided between the respective supports, and the two rack gears are engaged by a deviation in the rotational direction between the propeller support and the pin support. The propeller-type wind power generator according to claim 1, wherein the matching pinion gear rotates to change the pitch of the propeller. The propeller-type wind power generator according to claim 1, wherein the propeller support is composed of a pair of members, and the pin support is also composed of the pair of members.

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