CN201802556U - Vertical axis wind wheel preventing over rotational speed - Google Patents

Abstract

The utility model discloses a vertical axis wind wheel with speed limit and overspeed, which comprises a wind wheel shaft and two or more lift-type blades arranged on the wind wheel shaft, and two blades are arranged on the top of the wind wheel shaft Flat-plate damping blades, and blade quality asymmetrical design. When the wind rotor exceeds the speed, under the action of centrifugal force, the damping blades will deviate to produce a damping effect and limit the increase of the speed of the wind rotor. The higher the speed, the greater the offset of the damping blades and the greater the damping torque, limiting the increase in the speed at high wind speeds, so that the wind rotor can continue to operate efficiently at high wind speeds, and protect the overload operation of the wind rotor. The vertical axis wind rotor has the advantage of being able to operate within a wide range of wind speeds.

Description

A Vertical Axis Wind Wheel with Speed Limitation

technical field

The utility model relates to the technical field of lift-type vertical-axis wind turbines, in particular to a lift-type wind wheel with vertical-axis straight blades with limited output speed.

Background technique

The vertical axis wind turbine, under the same operating environment, has a slower speed than the horizontal axis, and the tip speed ratio is about 2 to 3. However, the wind strength that the vertical axis wind rotor structure can withstand is greater. If the wind turbine runs under strong wind or encounters a strong wind environment, the speed of the vertical axis wind rotor is also faster. At this time, if the speed of the vertical axis wind rotor is not limited, the generator cannot run efficiently, and it is easy to cause the wind turbine to be overloaded and damaged.

However, the speed-limiting technology of vertical-axis wind rotors has always been a difficult problem to solve. The horizontal axis wind rotor is closely connected with the large nacelle, and many pitch transmission systems can be installed in the airport to realize the pitch technology. However, due to the influence of the structure of the vertical axis wind rotor, it is impossible to learn from the pitch control technology of the horizontal axis, or adopt the stall design of the blade, or adopt the active stall control technology to limit the speed and power output of the wind rotor. It is also impossible to limit the rotational speed by imitating the method of reversing the direction of the horizontal axis wind rotor so that it does not face the wind. Therefore, the vertical axis wind rotor must take other measures to limit the increase in the speed of the wind rotor, otherwise the vertical axis wind rotor cannot operate under strong wind conditions. 25m/s wind speed) the advantages of running under strong wind cannot be realized in practice.

Therefore, it is necessary to design a method to limit the power output and speed of the vertical axis wind rotor after the rated wind speed.

Contents of the invention

The technical problem to be solved by the utility model is to solve the overspeed control of the vertical axis wind turbine, and provide a vertical axis straight blade lift type wind wheel with controllable rotating speed and which can operate under the rated output power.

In order to solve the above-mentioned technical problems, the technical solution adopted by the present invention is as follows: a vertical-axis wind rotor with limited speed overspeed, including a wind rotor shaft and 2 or more lift-type blades arranged on the wind rotor shaft. The wind rotor shaft is provided with a damping blade connected with the wind rotor shaft, the damping blade forms an opening angle with the axis of the wind rotor shaft under centrifugal action, and an outer cover is arranged on the upper end of the wind rotor shaft, and the upper end of the outer cover acts on the damping blade , there is a spring in the outer cover, and the spring acts on the damping blade through the upper end of the outer cover to provide a tightening force opposite to the direction of the centrifugal force.

The cylinder is radially fixed to the shaft, but can move up and down along the axial direction.

There are at least two damping blades, the blades are flat plate design, the lower end is connected with the shaft, and can rotate within the range of 0-90° in the axial direction.

The quality of the damping blades is not uniform, one side is high quality, and the other side is low quality.

The cylinder uses rollers to contact the flat blades, the purpose is to use rolling friction to reduce the friction force, so that the damping blades can be deflected smoothly.

Compared with the prior art, the beneficial effects of the lift type wind wheel speed limiting device of the present invention are:

1. Utilizing the mass eccentricity of the plate damping blade, the centrifugal force generated under overspeed is adaptively shifted to different degrees to generate damping torque. The damping torque can increase with the increase of the speed and decrease with the decrease of the speed, which is very good Limit speed increase.

2. The damping blade does not deflect within the rated speed, the two damping blades are closed, and are retracted in the cylinder by the action of the spring, which does not affect the overall performance of the wind wheel, let alone produce damping effect.

4. This method can really achieve high-efficiency and safe operation under high wind speeds, and makes better use of the strong winds brought by strong winds.

5. It can enhance the ability of the wind wheel to adapt to harsh environments in practice.

Description of drawings

Fig. 1 is an overall schematic diagram of a vertical axis wind rotor with speed limiting device in the present invention.

Fig. 2 is the structural representation of speed limiting device of the present invention

Fig. 3 is a schematic diagram of the structure of the damping vane of the present invention.

Fig. 4 is a schematic diagram of the overall schematic diagram of the wind rotor at high speed operation.

Among them: , wind wheel shaft; 2, lift type blade; 3, outer cover; 4, damping blade; 5, offset guide plate, 6, spring; 7, roller;

Detailed ways

1, below in conjunction with accompanying drawing, the present invention is described in detail. As shown in Figure 1, the device for limiting the overspeed of the vertical axis wind rotor of the present invention comprises a wind rotor shaft 1 on which 2 or more lift-type blades 2 are installed; cylinder 3, damping blade 4, damping Blade offset guide plate 5, spring 6, roller 7.

2. As shown in Figure 2, the bottom end of the damping vane 4 is connected to the shaft, and is guided by the offset guide plate 5 to limit the offset direction and angle, and the connection end and the guide plate 5 are used to transmit the damping torque.

3. As shown in Figure 2, when the wind speed is within the rated wind speed, the wind wheel rotates at a speed not exceeding the rated speed. Under the thrust of the spring 6 against the cylinder 3, the damping blades are closed at the center of the rotation axis, and most of them are hidden in the outer cover , does not affect the rotation of the wind wheel.

4. The damping blade 4 shown in Fig. 3 is designed for mass misalignment. Because the mass of one side is obviously larger than the other side, centrifugal force is generated at high speed, and the side with large mass drives the side with small mass to deflect and move. The damping moment generated by the damping vane increases with the increase of the offset

5. As shown in Figure 4, when the wind speed exceeds the rated wind speed and the speed of the wind rotor exceeds the speed, the centrifugal force of the damping blade 4 multiplied by the length of the blade is greater than the product of the elastic force of the cylinder and the damping point to the low end of the blade, that is, the deflection moment of the centrifugal force is greater than that of the cylinder The damping moment, the damping vane produces offset, and the damping vane produces a damping effect, which limits the speed to continue to rise to a certain extent.

6. When the wind speed continues to increase, or the rotation speed continues to increase, the offset of the damping blade 4 increases, and the resulting damping torque further increases, further limiting the increase in the rotation speed.

7. When the wind speed decreases, the rotational speed drops, and the centrifugal force generated by the damping blade 4 weakens. Under the driving force of the spring in the cylinder, the cylinder cover moves upwards to push the blades to close.

8. The torque generated by the lift-type wind rotor is small, so the design of slender damping blades can generate a large damping torque, thereby better limiting the increase in the speed of the wind rotor.

The utility model relates to a method for controlling the speed of a lift-type vertical axis, which utilizes the unevenness of the mass on both sides of the damping blade of the flat plate to generate an offset under the action of centrifugal force, and the blade after the offset produces a damping effect, thereby limiting the increase in the speed of the wind wheel . The higher the speed, the greater the deflection of the damping blade, the greater the damping torque generated, and the more effective the limit of the speed increase, so that the wind rotor can continue to operate efficiently at high wind speeds and prevent the overload operation of the wind rotor. This method is simple, effective, and true. In a sense, it shows the advantage that the vertical axis wind rotor can operate ratedly within a wide wind speed.

Claims (1)

1. vertical axis rotor that limits the lift-type over speed of rotation, comprise rotor shaft (1) and be arranged on 2 or 2 above lift-type blades (2) on the described rotor shaft, it is characterized in that: described rotor shaft (1) is provided with a damping vane that links to each other with rotor shaft (4), this damping vane (4) forms a subtended angle under the action of the centrifugal and between the rotor shaft axis, also be provided with an outer cover (3) in rotor shaft (2) upper end, the upper end of this outer cover (3) acts on the damping vane (4), spring (6) is arranged in outer cover (3), and this spring (6) acts on by outer cover (3) upper end a tightening force opposite with the centrifugal action direction is provided on the damping vane (4).

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