Vertical shaft-type wind power generator equipped with wind speed compliant movable device

Abstract

The present invention has a mechanism whereby, at low wind speeds, fins (5) are opened wide at the outside of a blade (1) and a generator (3) is rotated with strong torque to enable power generation in a weak wind and, in strong winds, the fins are stored inside of the blade to prevent excessive rotation, changed into a shape insensitive to wind strength, and changed into a shape generating braking force to avoid breakage. Furthermore, since gravity, centrifugal force, and the restoring force of a spring substitute for a power source required in the blade, no special power source from the outside is required.

Description

Vertical-axis wind turbine with a wind speed following movable device

[0001] The present invention relates to a vertical-axis wind turbine.

[0002] The appearance of a general vertical-axis wind turbine is shown in FIG. 1. However, since it does not rotate at low wind speeds, there is FIG. 2 which shows an improved blade of the wind turbine. The shape of the blade is also registered in Design Registration No. 1664759. By the way, although the blade shown in FIG. 2 has fins, the fins are fixed and do not have a movable structure.

[0003] Design Registration No. 1664759

[0004] The wind turbine shown in FIG. 2 has fixed fins attached to the rear of the blade that extends toward the rear of the blade with a standard airfoil cross-section on the outer surface of the blade (shown in FIG. 1). The wind turbine shown in FIG. 2 exhibits the effect of the fins in light winds, starts rotating earlier even at lower wind speeds than the airfoil cross-section type shown in FIG. 1, and exhibits amazing power generation. However, in strong winds, it may over-rotate and the wind turbine shown in FIG. 2 may be destroyed.

[0005] The present invention has conducted sincere research and provides the following means.

[0006] As means 1, a wind turbine comprising a generator, a hub provided in the generator, and blades provided in the spokes of the hub, the generator being attached to a support column or a tower, the blades being provided with movable fins, a pendulum provided in the spokes, a phase-fixed ring that can move up and down provided in the support column, a phase-fixed ring lug provided in the phase-fixed ring and connected to the pendulum via an up-and-down connecting rod, and the fins connected to the pendulum, and providing a vertical-axis wind turbine characterized in that it follows the rotational speed of the blades, the fins protrude when the rotational speed is low, and the fins close when the rotational speed is high.

[0007] As a means 2, a vertical-axis wind turbine is provided, comprising a generator, a hub provided on the generator, and blades provided on the spokes of the hub, wherein the generator is mounted on a support column or a steel tower, the blades are provided with movable fins, the spokes are provided with a horizontally moving pendulum, the outer circumference of the hub is provided with a horizontally movable phase fixing ring, a ring connecting rod is provided for transmitting the movement of the pendulum to the phase fixing ring, a spring is provided between the pendulum and the phase fixing ring, and the fins extend when the rotational speed is low and close when the rotational speed is high, in accordance with the rotational speed of the blades.

[0008] By the way, the horizontal direction refers to the direction parallel to the earth.

[0009] By the way, a "spring" can be any mechanism that has elastic properties and returns to its original shape, but a metal spring is preferred.

[0010] Compared to conventional fixed-fin wings, the fins extend outward in light winds, increasing the wind-receiving area and the radius over which wind force acts, thus increasing torque. This allows the turbine to start rotating in weaker winds than conventional wind turbines, and the wind speed required to begin generating electricity is also lower.

[0011] Furthermore, the "fins sticking outwards" occur during light winds. In light winds, the rotation speed decreases, reducing the centrifugal force on the pendulum. This causes the pendulum to sag, and the fins are designed to sag in this way.

[0012] On the other hand, with fixed-fin wind turbines, the rotation speed increases during strong winds, making it highly likely that over-rotation will damage the wind turbine. However, in this invention, the fins are retracted into the blades during strong winds, preventing over-rotation and thus preventing damage to the wind turbine. Therefore, it is possible to increase power generation by rotating well in light winds and reduce the increase in rotation speed during strong winds, thereby preventing damage to the wind turbine caused by over-rotation.

[0013] Furthermore, in this invention, since the phase-fixing ring is physically connected to all fins, the degree of opening and closing of all fins on all wings is the same. This action balances all wings and maintains rotational stability in strong winds. Incidentally, if this rotational stability is lost, vibrations and noise will occur, leading to the destruction of the wind turbine. Incidentally, when the wind speed decreases and the fins cannot hang down due to gravity, a structure can be added that uses a spring to pull the pendulum inward.

[0014] External view of a conventional airfoil-shaped wind turbine External view of a wind turbine with fixed (immovable) fins on the blade External view of a vertical-axis wind turbine with movable fins according to an embodiment of the present invention Enlarged view of the upper part of the embodiment of the present invention during light winds (fins open) Enlarged view of the upper part of the embodiment of the present invention during strong winds (fins closed) Internal structure diagram of the wing of an embodiment of the present invention Mechanism diagram of the wing cross-section according to an embodiment of the present invention (equipped with a pendulum that expands due to centrifugal force and returns due to gravity) Another example mechanism diagram of the wing cross-section according to an embodiment of the present invention (equipped with a pendulum that expands due to centrifugal force and returns due to a spring)

[0015] The following is merely an example illustrating how to implement the present invention. Figure 1 shows a conventional example of a generator of a type called a vertical-axis wind turbine. Conventionally, these wind turbines have been said to start rotating even at weak wind speeds, produce almost no noise and thus do not cause pollution, and are considered to have the best performance among vertical-axis wind turbines. Many models of wind turbines with airfoil-shaped blades, employing elaborate designs, are commercially available all over the world.

[0016] Generally, the starting wind speed is around 1.5 to 2 m / s. If the wind becomes too strong and the wind turbine rotates too fast, there is a possibility of damaging the wind turbine, so mechanical brakes may be installed in addition to electromagnetic brakes.

[0017] Incidentally, many wings employ a wing design called the Clark Y, with a wing thickness ratio of 17-20%, or a cross-section that generates high lift, similar to that of aircraft wings, in order to convert lift into rotation.

[0018] By the way, the hub is the key component that brings together the spokes that radiate outwards in all directions from a single axis of rotation, and it is an important part that always maintains a constant angle and positional relationship of each spoke. The hub consists of the hub disc, spokes, and hub waterproof cover. The hub disc is a disc that fixes the spokes to the input shaft of the generator, and it is made of a strong material that can withstand high rotation in strong winds and severe load fluctuations in windy conditions.

[0019] Figure 2 shows a conventional example of a vertical-axis wind vane generator with fins positioned on the outer surface of the wing. When the wing receives wind from the front during rotation, it smoothly directs the airflow, generating lift similar to an airfoil type, and when it receives wind from the rear, it generates strong drag, resulting in a synergistic effect that produces high rotational force and power generation.

[0020] Data from a prototype wind turbine with a blade thickness ratio of approximately 32%, created experimentally using a simplified test machine, showed that the wind turbine started rotating in light breezes of 1 m / s or less, and at wind speeds of 2-7 m / s (per second), its output was more than three times that of a typical airfoil-type wind turbine that prioritizes lift. This is a vertical-axis wind turbine featuring a hybrid blade that combines a lift-type airfoil with a drag-type airfoil that prioritizes wind from the tail.

[0021] Figure 3 is an external view of a wind turbine according to an embodiment of the present invention, which employs a wing with a movable fin, an improvement over the wing fins in Figure 2. The movable mechanism that swings the fins to change the wing's cross-section according to the wind speed combines gravity, centrifugal force, and the lever principle, thus requiring no external energy supply. When the wing does not rotate or rotates at a low speed, from no wind to a light breeze, there is almost no centrifugal force acting on the pendulum, and the fins are fully open with the weight hanging down, allowing it to efficiently catch the wind and rotate the wing even in a light breeze. As the wind speed gradually increases, centrifugal force acts on the pendulum, causing it to swing at an angle inversely proportional to the rotation speed. The force created by the weight screwed to the pendulum is converted into tension that drives the fins through a link mechanism, and the wing is autonomously controlled to swing to a cross-section appropriate to the wind speed.

[0022] In strong winds, the wings rotate at high speed, causing the pendulum to spring upwards and the fins to close completely, changing the wing thickness ratio to less than 30%. However, the outer surface at this time is different from the smooth surface of an airfoil; the strong curves and the bumps created by the fin joints are arranged like a washboard, generating turbulence. As a result, it is difficult to generate lift like an airfoil, and a braking effect is also generated, making over-rotation less likely.

[0023] Figure 4 shows that when the blades are not rotating or are rotating very slowly in calm to light wind conditions, and there is almost no centrifugal force acting on the pendulum, causing it to hang down, the fins are fully extended and the blade thickness ratio increases to around 40%. In our experiments, when the blade thickness ratio exceeds 30%, the starting wind speed is reduced to less than 1 m / s, and the wind speed at which power generation begins is also reduced accordingly.

[0024] The pendulum, suspended by the weight of the bore, swings around its pivot point, while the phase-fixing ring, equipped with a phase-fixing ring connecting lug, rotates freely around the support shaft via an upper and lower connecting rod, moving up and down. The phase-fixing ring restricts the irregular movement of the pendulum, and the combined force of the pendulum's weight and centrifugal force is transformed into a powerful tension through a mechanism that also incorporates the principle of leverage. This tension is transmitted through the pendulum-wing connecting rod to the linkage mechanism inside the wing, causing all the fins positioned on the wing to swing at the same timing and opening. The timing of when the fins begin to close and the force with which they close can be changed by removing the screw on the bore fixed to the pendulum and adjusting the weight of the bore.

[0025] Figure 5 shows the pendulum in its most expanded state when the wind speed increases and centrifugal force acts on it. As the wind speed increases, the pendulum bounces upward, and the weight of the pendulum changes direction at the pivot point, converting into tension that pulls the link mechanism inside the wing via the pendulum-wing connecting rod. Because the displacement of the wing, to which tension is transmitted, is limited via the phase-fixing ring, all the fins begin to close at the same time, and when the pendulum bounces to its highest point, the fins are fully closed. In strong winds, the wind turbine rotates faster, and at the same time, the centrifugal force acting on the pendulum also increases, so the force that closes the fins also increases, and the higher the wind turbine's rotation, the stronger the force that closes the fins.

[0026] Figure 6 shows the inside of the wing. Centrifugal force is transmitted from the pendulum to the fins inside the wing as tension through the pendulum wing connecting rod, fin rotation lever, fin rotation shaft, and fin rotation bell crank. This tension is supported by the bearings of the main spar frame and the bearing subframe perpendicular to it, pushing and pulling the fin rotation lever, which is integrated with the fin rotation shaft.

[0027] The fins, fixed to the fin rotation shaft via a connecting bell crank, can swing by pushing and pulling the fin rotation lever. Since the fin connecting bell crank is fixed to the fin rotation shaft and the fins are fixed to its outer surface, the aligned fins swing in proportion to the angle of the pendulum's movement.

[0028] Figure 7 shows a cross-sectional view of the wing. Because the cross-section when fully closed is basically based on an airfoil, the wing thickness ratio is 30% or less. The linkage mechanism and movable parts can be almost entirely housed within the wing, providing minimal protection from strong winds, rain, and direct sunlight, allowing for long-term use; however, regular inspections and maintenance are necessary.

[0029] Figure 8 is an external view of a generator with a pendulum that moves horizontally, in contrast to the standard-sized generator in Figure 3 where the pendulum moves vertically, to accommodate a larger diameter generator. When mounted on a large-diameter generator, the difference in diameter with the support shaft is large, resulting in excessive weight of the lug components and increased concerns about weight balance and strength. Therefore, the mechanism is designed to make the pendulum move horizontally, along with the phase fixing ring and connecting rod that move freely around the outer circumference of the hub disc.

[0030] When a pendulum moves vertically, gravity acts on it when it is stationary and no centrifugal force is acting on it, causing the pendulum to hang down. However, when a pendulum moves horizontally, gravity cannot return the pendulum to the center, so a spring pulls it back to the center, producing the same effect as when gravity causes the pendulum to hang down. The spring is preferably a metal coil spring, but it is not limited to that; any spring with elasticity will do. Examples include resin springs, rubber, and dampers.

[0031] The phase fixing ring is positioned on the outer circumference of the hub disc, resulting in a larger diameter. However, the phase fixing ring lugs become unnecessary, and the upper and lower connecting rods are also unnecessary, being replaced by smaller connecting rods, resulting in a weight equivalent to the original.

[0032] 1. Wing 2. Hub 201. Hub Disc 202. Spoke 203. Hub Waterproof Cover 3. Generator 4. Support Shaft 5. Fin 6. Phase Fixing Ring 7. Phase Fixing Ring Lug 8. Upper and Lower Connecting Rod 9. Pendulum 10. Weight 11. Weight Fixing Screw 12. Pendulum Pivot 13. Pendulum Wing Connecting Rod 14. Fin Rotation Lever 15. Fin Rotation Shaft 16. Fin Connecting Bell Crank 17. Fin Connecting Rod 18. Main Spasm Frame 19. Bearing Subframe 20. Ring Connecting Rod 21. Spring

Claims

1. A vertical-axis wind turbine comprising a generator, a hub provided on the generator, and blades provided on the spokes of the hub, wherein the generator is mounted on a support column or a steel tower, the blades are provided with movable fins, a pendulum provided on the spokes, a vertically movable phase fixing ring provided on the support column, a phase fixing ring lug provided on the phase fixing ring and connected to the pendulum via an upper and lower connecting rod, and the fins connected to the pendulum, wherein the fins extend when the rotational speed is low and close when the rotational speed is high, in accordance with the rotational speed of the blades.

2. A vertical-axis wind turbine comprising a generator, a hub provided on the generator, and blades provided on the spokes of the hub, wherein the generator is mounted on a support column or a steel tower, the blades are provided with movable fins, the spokes are provided with a horizontally moving pendulum, the outer circumference of the hub is provided with a horizontally movable phase fixing ring, a ring connecting rod is provided for transmitting the movement of the pendulum to the phase fixing ring, a spring is provided between the pendulum and the phase fixing ring, the pendulum is connected to the fins, and the fins follow the rotational speed of the blades, with the fins extending when the rotational speed is low and closing when the rotational speed is high.

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