Load control and shutdown protection structure of large vertical axis wind generating set

Abstract

The invention discloses a load control and shutdown protection structure of a large vertical axis wind generating set, and relates to the technical field of wind power generation equipment. The blades are connected with the rotating shaft through connecting rods; and the adjusting mechanism is used for adjusting the blade attack angle. In the operation process of the wind turbine, the driving assembly, the connecting rod and the straight bevel gears can drive the blades and the connecting rod to rotate so as to adjust the attack angle of the blades. When the wind turbine is started, the wind wheel starting torque can be improved by changing the attack angle of the blades, extra power needed by starting is reduced, and then the power generation cost is reduced. When the wind speed is higher than the cut-out wind speed, the load acting on the blade exceeds the bearing limit of the generator, the pitch angle of the blade can be changed in a linkage mode by changing the attack angle of the blade, the blade generates large resistance, the rotating speed of the rotating shaft is reduced, and the wind turbine can work under the working condition of higher wind speed. And the working range and application region of the unit are expanded.

Description

Technical Field

[0001] The invention relates to the technical field of wind power generation equipment, and in particular to a load control and shutdown protection structure for a large vertical axis wind power generator set. Background Art

[0002] Wind energy can be converted into electrical energy for use by wind turbines. Among wind turbines, vertical axis wind turbines have the advantages of simple structure and no need for yaw-to-wind devices, and are widely used in various wind power generation fields.

[0003] The H-type vertical axis wind turbine is a common vertical axis wind turbine. Its wind rotor device is composed of blades, brackets and main shafts. The brackets are used to connect the blades and the main shaft to form an H-shaped frame structure with a certain rigidity. During structural design, the wind rotor device is usually set with a fixed installation angle. However, in actual use, due to the high instability and randomness of wind energy, when wind acts on the wind rotor device, complex and diverse loads will be generated on the blades. Limited by the fixed installation angle of the wind rotor device, the blades cannot change their angles adaptively to the wind load. When the wind speed reaches the cut-out wind speed, the unit must be in a shutdown state to ensure the safety of the overall structure. At the same time, when the wind speed is low, the unit is difficult to start and requires additional power to start.

[0004] Therefore, the existing wind turbine device will cause wind energy waste and increase the cost of power generation, and there are also safety risks under high wind speed conditions. In view of this, how to provide a wind turbine that can adapt to complex and diverse wind loads, improve wind energy utilization, and reduce safety risks under high wind speed conditions is a problem that technicians in this field need to solve urgently. Summary of the invention

[0005] The purpose of the present invention is to provide a load control and shutdown protection structure for a large vertical axis wind turbine generator set to solve the problems existing in the prior art.

[0006] To achieve the above object, the present invention provides a load control and shutdown protection structure for a large vertical axis wind turbine generator set, comprising:

[0007] Axis of rotation;

[0008] A blade connected to the rotating shaft via a connecting rod;

[0009] The adjusting mechanism is used to adjust the blade angle of attack.

[0010] Furthermore, the regulating mechanism comprises:

[0011] A first spur bevel gear, fixedly connected to the blade, with its axis arranged along the length direction of the blade;

[0012] A second spur bevel gear, disposed at one end of the connecting rod and meshingly connected with the first spur bevel gear;

[0013] The third spur bevel gear is arranged at the other end of the connecting rod and meshes with the transmission gear on the output end of the driving assembly. The driving assembly is fixedly connected to the rotating shaft. When the driving assembly drives the third spur bevel gear to rotate, the first spur bevel gear drives the blade to rotate and changes the blade attack angle.

[0014] Furthermore, the adjustment range of the blade attack angle is -8° to 13°, the transmission ratio between the transmission gear and the third spur bevel gear is 1:1, and the transmission ratio between the second spur bevel gear and the first spur bevel gear is 3.5.

[0015] Furthermore, a side of the blade close to the rotating shaft is recessed inward to form a receiving cavity, a mounting shaft is arranged in the receiving cavity along the length direction of the blade, and the first spur bevel gear is fixedly arranged on the mounting shaft.

[0016] Furthermore, a sealing housing is provided at the connection between the first spur bevel gear and the second spur bevel gear, and at the connection between the third spur bevel gear and the transmission gear.

[0017] Furthermore, it also includes a hinge mechanism, one end of which is fixedly connected to the blade, and the other end of which is fixedly connected to the rotating shaft.

[0018] The present invention discloses the following technical effects:

[0019] During the operation of the wind turbine, the blades can be rotated by the drive assembly, connecting rod and multiple straight bevel gears to adjust the blade angle of attack. When the wind turbine is started, the starting torque of the wind rotor can be increased by changing the blade angle of attack, reducing the additional power required for starting and thus reducing the cost of power generation. When the wind speed reaches above the cut-out wind speed, the load acting on the blades has exceeded the working limit of the generator. The blade angle of attack can be changed to change the blade pitch angle, so that the blades produce greater resistance, reduce the speed of the rotating shaft, and enable the wind turbine to operate under higher wind speed conditions, expanding the working range and applicable area of ​​the unit. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic diagram of the structure of the present invention;

[0022] Figure 2 It is a schematic diagram of the connection between a single blade and a rotating shaft;

[0023] Figure 3 is a schematic diagram of the connecting rod structure;

[0024] Figure 4 is a schematic diagram of the blade structure;

[0025] Figure 5 It is the schematic diagram of blade force;

[0026] Figure 6 is the curve of aerodynamic moment changing with azimuth;

[0027] Figure 7 is the curve of aerodynamic moment changing with time;

[0028] Figure 8 It is the changing curve of wind turbine under different wind speeds;

[0029] Among them, 1. blade; 2. rotating shaft; 3. connecting rod; 4. mounting shaft; 5. hinge mechanism; 6. driving assembly; 7. second spur bevel gear; 8. third spur bevel gear; 9. first spur bevel gear; 10. transmission gear. DETAILED DESCRIPTION

[0030] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0031] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0032] Example 1

[0033] like Figure 1-Figure 4 As shown, an embodiment of the present invention discloses a load control and shutdown protection structure for a large vertical axis wind turbine generator set, comprising: a rotating shaft 2, which is connected to a power generation unit and is a component for converting wind power into electrical energy; blades 1, which are connected to the rotating shaft 2 through a connecting rod 3, and the blades 1 can rotate using wind power and drive the rotating shaft 2 to rotate synchronously; and an adjusting mechanism for adjusting the angle of attack of the blades 1.

[0034] In this embodiment, the adjustment mechanism includes: a first spur bevel gear 9, which is fixedly connected to the blade 1, and its axis is arranged along the length direction of the blade 1; a second spur bevel gear 7, which is arranged at one end of the connecting rod 3 and meshed with the first spur bevel gear 9; a third spur bevel gear 8, which is arranged at the other end of the connecting rod 3 and meshed with the transmission gear 10 on the output end of the drive assembly 6, and the drive assembly 6 is fixedly connected to the rotating shaft 2. When the drive assembly 6 drives the third spur bevel gear 8 to rotate, the first spur bevel gear 9 drives the blade 1 to rotate and changes the angle of attack of the blade 1. The drive assembly 6 can be a motor, a hydraulic device or other drive structure suitable for loading in the rotating shaft 2.

[0035] Experiments have found that the angle of attack of the blade 1 between -8° and 13° is beneficial to improving the overall performance of the unit, so in this embodiment, the transmission ratio of the transmission gear 10 to the third spur bevel gear 8 is 1:1, and the transmission ratio of the second spur bevel gear 7 to the first spur bevel gear 9 is 3.5. The above transmission ratio can achieve the adjustment of the angle of attack of the blade 1 relative to the connecting rod 3 within the range of -8° to 13°, so as to adapt to complex and diverse wind loads and improve the utilization rate of wind energy.

[0036] In the present embodiment, one side of the blade 1 close to the rotating shaft 2 is recessed inward to form an accommodating cavity, and a mounting shaft 4 is arranged in the accommodating cavity along the length direction of the blade 1, and the first spur bevel gear 9 is fixedly arranged on the mounting shaft 4. A sealing shell is arranged at the connection between the first spur bevel gear 9 and the second spur bevel gear 7, and at the connection between the third spur bevel gear 8 and the transmission gear 10. The function of the sealing shell is to improve the stability of the wind turbine and avoid shaking or deformation during operation. One end of the hinge mechanism 5 is fixedly connected to the blade 1, and the other end is fixedly connected to the rotating shaft 2. The function of the hinge mechanism 5 is to connect the blade 1 and other rods used for fixing, etc. In the present embodiment, a set of hinge mechanisms 5 are respectively arranged near the upper and lower ends of the blade 1 to further improve the stability and safety of the wind turbine.

[0037] Figure 5 The figure shows the load diagram of blade 1, where F L The lift force on blade 1 is also the main source of aerodynamic torque of blade 1. D is the resistance force exerted on the blade 1. This force will generate a negative torque during the rotation of the blade 1, thereby affecting the power of the vertical axis wind turbine generator set.

[0038] The present invention controls the blade 1 attack angle The aerodynamic force on blade 1 is adjusted to control the load and power generation of blade 1. The airfoil blade 1 is used in engineering mainly to obtain lift. According to Zhukovsky's theorem, the lift resistance and the moment M of the resultant force on the leading edge of blade 1 are calculated as follows:

[0039]

[0040] Where C L , C D , C M are the lift and drag coefficient and moment coefficient of blade 1, respectively, and they are related to the angle of attack of blade 1. Related to the Reynolds number.

[0041] like Figure 6 and Figure 7 As shown, due to the high instability and randomness of wind energy, the aerodynamic moment of blade 1 will show periodicity and significant instability, which usually reduces the utilization efficiency of wind energy. The "before control" curve represents that blade 1 is a fixed installation angle, and the "after control" curve represents that blade 1 can adjust the angle of attack through this embodiment. After the angle of attack of blade 1 is controlled by this embodiment, the volatility of the aerodynamic moment of blade 1 is significantly reduced, which can improve the utilization rate of wind energy.

[0042] like Figure 8 As shown, after adopting the device disclosed in this embodiment, the angle of attack of blade 1 is adjustable, and the angle of attack of blade 1 is increased during the startup phase (increasing the angle of attack can reduce the pitch angle, thereby increasing the power output of the wind turbine) to capture more wind energy and increase the lift of blade 1, making it easier to start the wind turbine at the same wind speed. This not only optimizes the power output of the wind turbine, but also improves its overall energy efficiency.

[0043] As the wind speed increases, it gradually reaches a high wind speed stage. In the high wind speed stage, the angle of attack of blade 1 is reduced (reducing the angle of attack of blade 1 can increase the pitch angle, thereby reducing lift, limiting the power output of the wind turbine, and preventing mechanical overload) and the windward area of ​​connecting rod 3 to reduce the load and torque on the unit, thereby ensuring that the unit can operate normally at high wind speeds and ensuring the stability of power generation, power generation and unit load.

[0044] Example 2

[0045] The difference between this embodiment and the first embodiment is that a wind speed sensing mechanism, a blade 1 angle of attack monitoring mechanism, a wind direction sensing mechanism and a controller are provided on the wind turbine, and a blade 1 angle of attack adjustment program is set in the controller. The controller can automatically adjust the blade 1 angle of attack according to the wind speed and wind direction, and can also automatically adjust the blade 1 angle of attack during the start-up phase and high wind speed phase of the blade 1, thereby realizing full automation of wind turbine power generation.

[0046] In the description of the present invention, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0047] The embodiments described above are only descriptions of the preferred modes of the present invention, and are not intended to limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made to the technical solutions of the present invention by ordinary technicians in this field should all fall within the protection scope determined by the claims of the present invention.

Claims

1. A load control and shutdown protection structure for a large vertical axis wind turbine generator set, characterized in that: include: Axis of rotation (2); The blade (1) is connected to the rotating shaft (2) via a connecting rod (3); The adjusting mechanism is used to adjust the angle of attack of the blade (1).

2. A large vertical axis wind turbine load control and shutdown protection structure according to claim 1, characterized in that: The regulating mechanism comprises: A first spur bevel gear (9) is fixedly connected to the blade (1), and its axis is arranged along the length direction of the blade (1); a second spur bevel gear (7) disposed at one end of the connecting rod (3) and meshingly connected with the first spur bevel gear (9); A third spur bevel gear (8) is arranged at the other end of the connecting rod (3) and meshes with a transmission gear (10) on the output end of a driving assembly (6); the driving assembly (6) is fixedly connected to the rotating shaft (2); when the driving assembly (6) drives the third spur bevel gear (8) to rotate, the first spur bevel gear (9) drives the blade (1) to rotate and changes the attack angle of the blade (1).

3. A large vertical axis wind turbine load control and shutdown protection structure according to claim 2, characterized in that: The blade (1) has an attack angle adjustment range of -8° to 13°, a transmission ratio between the transmission gear (10) and the third spur bevel gear (8) is 1:1, and a transmission ratio between the second spur bevel gear (7) and the first spur bevel gear (9) is 3.

5.

4. A large vertical axis wind turbine load control and shutdown protection structure according to claim 2, characterized in that: The side of the blade (1) close to the rotating shaft (2) is recessed inward to form a receiving cavity, and a mounting shaft (4) is arranged in the receiving cavity along the length direction of the blade (1), and the first spur bevel gear (9) is fixedly arranged on the mounting shaft (4).

5. A large vertical axis wind turbine load control and shutdown protection structure according to claim 4, characterized in that: A sealing housing is provided at the connection between the first spur bevel gear (9) and the second spur bevel gear (7) and at the connection between the third spur bevel gear (8) and the transmission gear (10).

6. A large vertical axis wind turbine load control and shutdown protection structure according to claim 2, characterized in that: It also comprises a hinge mechanism (5), one end of which is fixedly connected to the blade (1), and the other end of which is fixedly connected to the rotating shaft (2).

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