Pitch control system and wind turbine

Abstract

The present application provides a pitch control system and a wind turbine. The pitch control system applied to the wind turbine rotor includes a pitch cylinder, an oil circuit, a mechanical valve and a valve mechanical control mechanism. The pitch cylinder is used to connect with the rotor; the oil circuit is connected to the pitch cylinder; the mechanical valve is connected to the oil circuit and is used to control the opening or closing of the oil circuit. When the rotational speed of the rotor does not exceed the overspeed rotational speed, the mechanical valve is closed; the valve mechanical control mechanism is connected to the mechanical valve and is used to connect with the rotating shaft of the rotor. When the rotational speed of the rotor exceeds the overspeed rotational speed, the valve mechanical control mechanism moves relative to the mechanical valve along with the rotation of the rotating shaft of the rotor, triggering the mechanical valve to open, so that the rotor pitches.

Description

Technical Field

[0001] This application relates to the field of wind power generation, and in particular to a pitch control system and a wind turbine generator. Background Art

[0002] With the development of wind power generation technology, like hydraulic machinery, wind turbine generators, as a power source, replace human and animal power and play an important role in the development of productivity. Wind turbine generators can convert wind energy into mechanical energy.

[0003] A wind turbine generator may include a wind rotor and a pitch control system connected to the wind rotor. The wind rotor includes a plurality of blades. The plurality of blades facilitate the rotation of the wind rotor so that wind energy can be converted into usable mechanical energy and then into electrical energy. The pitch control system mostly adopts a hydraulic pitch control system. The hydraulic pitch control system realizes the pitching of the blades by electronically controlling solenoid valves and proportional control valves.

[0004] In the application of related technologies, when the wind rotor runs at an overspeed in strong winds, the pitch control system controls the solenoid valves and proportional control valves to make the blades of the wind rotor achieve feathering, avoiding overspeed stall of the wind rotor.

[0005] However, once the pitch control system loses power, the solenoid valves and proportional control valves cannot be opened or closed. Thus, when the wind rotor runs at an overspeed, the stall of the wind rotor is out of control, and the safety and reliability of the pitch control system in related technologies are relatively low. Summary of the Invention

[0006] This application provides an improved pitch control system and a wind turbine generator.

[0007] This application provides a pitch control system applied to the wind rotor of a wind turbine generator. The pitch control system includes:

[0008] A pitch cylinder for connecting to the wind rotor;

[0009] An oil circuit connected to the pitch cylinder;

[0010] A mechanical valve connected to the oil circuit for controlling the opening or closing of the oil circuit. When the rotational speed of the wind rotor does not exceed the overspeed rotational speed, the mechanical valve is closed; and

[0011] A valve mechanical control mechanism connected to the mechanical valve and used for connecting to the rotating shaft of the wind rotor. When the rotational speed of the wind rotor exceeds the overspeed rotational speed, the valve mechanical control mechanism moves relative to the mechanical valve with the rotation of the rotating shaft of the wind rotor, triggering the mechanical valve to open.

[0012] Optionally, the valve mechanical control mechanism includes a centrifugal motion component and a transmission member. The transmission member is respectively connected to the centrifugal motion component and the mechanical valve. The centrifugal motion component is used to be connected to the rotating shaft. When the rotating shaft rotates, a centrifugal motion is generated. When the rotational speed of the wind wheel exceeds the overspeed rotational speed, the transmission member is driven to move relative to the mechanical valve, triggering the mechanical valve to open.

[0013] Optionally, the centrifugal motion component includes a rotating component and a centrifugal extrusion member; wherein,

[0014] The rotating component is used to be connected to the rotating shaft. The rotating component includes a first opening and closing body and a second opening and closing body which are oppositely arranged. An accommodating space is formed between the first opening and closing body and the second opening and closing body. The first opening and closing body can move relative to the second opening and closing body. The first opening and closing body is connected to the transmission member. Both the first opening and closing body and the second opening and closing body are used to be connected to the rotating shaft and rotate when the rotating shaft rotates;

[0015] The centrifugal extrusion member is movably arranged in the accommodating space. When the rotational speed of the wind wheel exceeds the overspeed rotational speed, the centrifugal extrusion member performs a centrifugal motion, driving the first opening and closing body to move relative to the second opening and closing body so as to drive the transmission member to move.

[0016] Optionally, the first opening and closing body and the second opening and closing body are oppositely arranged in the axial direction of the rotating shaft, and the first opening and closing body can move relative to the second opening and closing body in the axial direction of the rotating shaft;

[0017] and / or,

[0018] The centrifugal extrusion member is a sphere;

[0019] and / or,

[0020] The first opening and closing body and the second opening and closing body are respectively discs.

[0021] Optionally, the middle parts of the first opening and closing body and the second opening and closing body are used to be connected to the rotating shaft; the distance between the edge of the first opening and closing body and the edge of the second opening and closing body is less than the distance between the middle parts of the first opening and closing body and the second opening and closing body.

[0022] Optionally, the first opening and closing body includes a first main body part and a first edge part connected to the edge of the first main body part. The first main body part is used to be connected to the rotating shaft. The first edge part extends obliquely from the first main body part in the direction towards the edge of the first opening and closing body and towards the second opening and closing body;

[0023] and / or,

[0024] The second opening and closing body includes a second main body portion and a second side portion connected to the edge of the second main body portion. The second main body portion is used for connecting to the rotating shaft, and the second side portion extends obliquely from the second main body portion in the direction towards the edge of the second opening and closing body and towards the first opening and closing body.

[0025] Optionally, the valve mechanical control mechanism includes an elastic member that abuts against the first opening and closing body and is used to provide an elastic force in the opposite direction to the movement of the first opening and closing body relative to the second opening and closing body.

[0026] Optionally, the valve mechanical control mechanism includes a first limiting member located on the side of the first opening and closing body facing away from the second opening and closing body. The first limiting member is used for fixedly connecting to the rotating shaft, and the elastic member elastically abuts between the first opening and closing body and the first limiting member;

[0027] and / or,

[0028] The valve mechanical control mechanism includes a second limiting member for fixedly connecting to the rotating shaft, and the second limiting member is located on the side of the second opening and closing body facing away from the first opening and closing body.

[0029] Optionally, the transmission member includes a transmission connection end that contacts the centrifugal motion assembly. When the centrifugal motion assembly rotates with the rotating shaft, it rotates relative to the transmission connection end.

[0030] Optionally, the transmission member is a connecting rod, and the transmission connection end is the end of the connecting rod close to contacting the centrifugal motion assembly.

[0031] Optionally, the pitch control system includes an electric control valve and an electric control mechanism connected to the electric control valve. The electric control valve is connected to the oil circuit.

[0032] This application also provides a wind turbine, which includes:

[0033] A tower;

[0034] A nacelle installed on the tower;

[0035] A wind wheel assembled in the nacelle;

[0036] The pitch control system as described above, which is arranged in the nacelle and connected to the wind wheel.

[0037] According to the technical solution provided by the embodiments of the present application, the pitch control system includes a pitch cylinder, an oil circuit, a mechanical valve, and a valve mechanical control mechanism. In this way, when the rotational speed of the wind turbine shaft exceeds the overspeed rotational speed, the valve mechanical control mechanism can be driven to forcibly open the mechanical valve, enabling high-pressure oil to enter the pitch cylinder, ensuring the feathering of the wind turbine, independent mechanical control, and improving the safety and reliability of the pitch control system. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 The following shows a schematic structural diagram of an embodiment of the wind turbine of the present application;

[0039] Figure 2 For Figure 1 The following shows a schematic structural diagram of an embodiment of the pitch control system in the wind turbine shown;

[0040] Figure 3 For Figure 1 The following shows a partial schematic structural diagram of the pitch control system in the wind turbine shown;

[0041] Figure 4 For Figure 2 The following shows a schematic diagram of the valve mechanical control mechanism when the rotational speed of the wind turbine exceeds the overspeed rotational speed in the pitch control system shown;

[0042] Figure 5 For Figure 2 The following shows a schematic diagram of the valve mechanical control mechanism when the rotational speed of the wind turbine does not exceed the overspeed rotational speed in the pitch control system shown. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0043] Here, the exemplary embodiments will be described in detail, and the examples are shown in the drawings. When the following description refers to the drawings, unless otherwise indicated, the same numbers in different drawings represent the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present application. On the contrary, they are merely examples of devices consistent with some aspects of the present application as detailed in the appended claims.

[0044] The terms used in this application are for the purpose of describing specific embodiments only and are not intended to limit this application. Unless otherwise defined, the technical or scientific terms used in this application shall have the ordinary meanings as understood by those of ordinary skill in the art to which this application pertains. The use of the words "a" or "an" and the like in the specification and claims of this application also do not denote a limitation of quantity, but rather mean that there is at least one. "Plurality" includes two, which is equivalent to at least two. The use of words such as "comprises" or "comprising" means that the elements or items appearing before "comprises" or "comprising" cover the elements or items listed after "comprises" or "comprising" and their equivalents, and does not exclude other elements or items. The use of words such as "connected" or "coupled" and the like is not limited to physical or mechanical connections, and may include electrical connections, whether direct or indirect. The singular forms of "a", "the", and "said" used in the specification and appended claims of this application are also intended to include the plural forms unless the context clearly dictates otherwise. It should also be understood that the term "and / or" as used herein refers to and encompasses any and all possible combinations of one or more of the associated listed items.

[0045] Figure 1 Shown is a schematic structural view of an embodiment of a wind turbine 10 of this application. Figure 2 For Figure 1 Shown is a schematic structural view of an embodiment of a pitch control system 20 in the wind turbine 10 shown.

[0046] As Figure 1 Shown, the wind turbine 10 includes a tower 12 extending from a support surface 11, a nacelle 13 mounted on the tower 12, and a rotor 14 assembled to the nacelle 13. The rotor 14 includes a rotatable hub 15 and at least one blade 16, and the blade 16 is connected to the hub 15 and extends outward from the hub 15. In Figure 1 the embodiment shown, the rotor 14 includes three blades 16. In some other embodiments, the rotor 14 may include more or fewer blades 16. The plurality of blades 16 may be spaced apart around the hub 15 to facilitate rotation of the rotor 14 so that wind energy can be converted into useful mechanical energy and then into electrical energy.

[0047] As Figure 2As shown, the wind turbine 10 includes a generator 17 and a pitch control system 20. The generator 17 is disposed within the nacelle 13 and can be coupled to the wind rotor 14. The generator 17 can convert the rotational energy generated when each blade 16 of the wind rotor 14 rotates to a desired operating position during operation into electrical power. The pitch control system 20 is disposed within the nacelle 13 and is connected to the wind rotor 14. The pitch control system 20 can rotate each blade 16 of the wind rotor 14 to a desired operating position and to a feather position during operation. The blade 16 at the desired operating position enables the wind to drive the wind rotor 14. The blade 16 in the feather position has the least resistance to the wind.

[0048] Among them, the pitch control system 20 can implement the function of over-speed protection for the wind turbine 10. The over-speed protection function of the pitch control system 20 can protect the wind rotor 14 against mechanical stress in the case of over-speed in strong winds. The over-speed situation occurs when the rotational speed of the rotating shaft 26 of the wind rotor 14 exceeds a specific range or threshold value, and the rotational speed of the rotating shaft 26 within this specific range or threshold value can be referred to as the over-rotation speed. During the over-speed situation, the wind rotor 14 may be subjected to huge mechanical stress that can cause the components of the wind rotor 14 to fail. The pitch control system 20 activates the over-speed protection function to protect the wind rotor 14 by initiating an emergency shutdown of the wind rotor 14 during the over-speed situation. This emergency shutdown can be achieved by feathering the blades 16 of the wind rotor 14 to avoid over-rotation stall of the wind rotor 14.

[0049] Continue as Figure 2 As shown, the pitch control system 20 includes a pitch cylinder 21, an oil circuit 22, an electro-hydraulic valve 23, a valve electro-control mechanism 24, a mechanical valve 25, and a valve mechanical control mechanism 30.

[0050] The pitch cylinder 21 is connected to the wind rotor 14, and the oil circuit 22 is connected to the pitch cylinder 21. The pitch cylinder 21 can form a hydraulic circuit with the oil circuit 22. The electro-hydraulic valve 23 and the mechanical valve 25 are respectively connected to the oil circuit 22 and can control the flow rate of the oil circuit 22 in the hydraulic circuit. The valve electro-control mechanism 24 is connected to the electro-hydraulic valve 23 and can control the opening or closing of the electro-hydraulic valve 23. The valve mechanical control mechanism 30 is connected to the mechanical valve 25 and can control the opening or closing of the mechanical valve 25. And either the valve electro-control mechanism 24 or the valve mechanical control mechanism 30 operates.

[0051] Among them, the mechanical valve 25 controls the opening or closing of the oil circuit 22. When the rotational speed of the wind turbine 14 does not exceed the overspeed rotational speed, the mechanical valve 25 is closed. The valve mechanical control mechanism 30 is used to connect with the rotating shaft 26 of the wind turbine 14. When the rotational speed of the wind turbine 14 exceeds the overspeed rotational speed, the mechanical control is forcibly started and moves relative to the mechanical valve 25 along with the rotation of the rotating shaft 26 of the wind turbine 14, triggering the mechanical valve 25 to open. By adopting the mechanical control of the valve mechanical control mechanism 30, the mechanical valve 25 is mechanically opened to control the opening or closing of the oil circuit 22, and further control the opening or closing of the pitch cylinder 21. In this way, when the rotational speed of the rotating shaft 26 of the wind turbine 14 exceeds the overspeed rotational speed, the valve mechanical control mechanism 30 can be driven to forcibly open the mechanical valve 25, enabling high-pressure oil to enter the pitch cylinder 21, ensuring the feathering of the wind turbine 14, with independent mechanical control, and improving the safety and reliability of the pitch control system 20.

[0052] Figure 3 For Figure 1 a partial structural schematic diagram of the pitch control system 20 in the wind turbine 10 shown.

[0053] As Figure 2 and Figure 3 shown, in some application examples, when the electric control valve 23, the valve electric control mechanism 24, and the wire 27 of the valve electric control mechanism 24 are all working properly, when the blade 16 experiences overspeed, the valve electric control mechanism 24 generates a control signal to control the opening of the electric control valve 23, causing the oil circuit 22 to open, the high-pressure oil flow rate in the hydraulic circuit to increase rapidly and enter the pitch cylinder 21, and the pitch cylinder 21 to operate directly to achieve feathering. At this time, the blade 16 is controlled by the electric control valve 23, and the electric control valve 23 is fully opened to achieve overspeed protection, while the valve mechanical control mechanism 30 at this time has not been affected by the overspeed condition of the wind turbine 14 and does not function. Among them, the electric control valve 23 can include a solenoid valve 231 and a proportional control valve 232. In this way, control signals are sent according to the system control requirements to control the solenoid valve 231 and the proportional control valve 232 to achieve pitching.

[0054] When any one or more of the electric control valve 23, the valve electric control mechanism 24, and the wire 27 of the valve electric control mechanism 24 fail or lose power, it indicates that the electric control fails. When the blade 16 runs at an overspeed, the valve mechanical control mechanism 30 opens the mechanical valve 25, and then opens the oil circuit 22, so that the high-pressure oil bypasses the proportional control valve 232 and the solenoid valve 231 from the P port and enters the pitch cylinder 21. The pitch cylinder 21 operates directly to push the blade 16 to quickly pitch and stop rotating, realizing overspeed protection for the wind turbine 14. At this time, the blade 16 is controlled by the mechanical valve 25, and the mechanical valve 25 is fully opened to achieve overspeed protection. In this way, when the electric control fails and cannot pitch in strong wind weather in time, the mechanical control mechanism 30 can provide overspeed protection, avoid accidents of the wind turbine 14 running at an overspeed, protect the safety of the wind power generator 10 and personnel, and further avoid the occurrence of a tower collapse accident in more serious cases. The details are introduced as follows.

[0055] Figure 4 For Figure 2 Schematic diagram of the valve mechanical control mechanism 30 in the pitch control system 20 shown when the rotational speed of the wind turbine 14 exceeds the overspeed rotational speed. Figure 5 For Figure 2 Schematic diagram of the valve mechanical control mechanism 30 in the pitch control system 20 shown when the rotational speed of the wind turbine 14 does not exceed the overspeed rotational speed.

[0056] As Figure 4 As shown, the valve mechanical control mechanism 30 includes a centrifugal motion component 31 and a transmission member 32. The centrifugal motion component 31 can drive the transmission member 32 to move, so that the transmission member 32 opens the mechanical valve 25. In this way, the mechanical valve 25 is opened by the transmission member 32 under the action of centrifugal force. The transmission member 32 is respectively connected to the centrifugal motion component 31 and the mechanical valve 25. The centrifugal motion component 31 is used to be connected to the rotating shaft 26. When the rotating shaft 26 rotates, centrifugal motion is generated. When the rotational speed of the wind turbine 14 exceeds the overspeed rotational speed, it drives the transmission member 32 to move relative to the mechanical valve 25, triggering the mechanical valve 25 to open. Among them, when the centrifugal motion component 31 generates centrifugal motion, this centrifugal motion can generate an opening force and transmit the force to the transmission member 32. The transmission member 32 transmits the force to the mechanical valve 25, and then opens the mechanical valve 25. In this way, the centrifugal motion component 31 and the transmission member 32 can trigger the opening of the mechanical valve 25. The mechanical transmission is simple, not limited by power supply, nor by the purity of oil. It can still work even when the valve electric control mechanism 24 fails, making the reliability of the pitch control system 20 relatively high. In this way, when the rotational speed of the rotating shaft 26 of the wind turbine 14 exceeds the overspeed rotational speed, the valve mechanical control mechanism 30 is driven. Under the action of centrifugal force, the transmission member 32 is pushed to forcibly open the mechanical valve 25, so that the high-pressure oil can enter the pitch cylinder 21. The high-pressure oil pushes the pitch cylinder 21 to drive the blade 16 to quickly pitch, avoiding accidents caused by the wind turbine 14 running at an overspeed and stalling.

[0057] Continue Figure 4 As shown, the centrifugal motion assembly 31 includes a rotating assembly 33 and a centrifugal extrusion member 34. Among them, the rotating assembly 33 can provide power for the centrifugal motion of the centrifugal extrusion member 34, so that the centrifugal extrusion member 34 performs centrifugal motion in the direction away from the centripetal force of the rotating assembly 33. The rotating assembly 33 is used to connect with the rotating shaft 26. The rotating assembly 33 includes a first opening and closing body 331 and a second opening and closing body 332 arranged oppositely. A receiving space 333 is formed between the first opening and closing body 331 and the second opening and closing body 332. The first opening and closing body 331 can move relative to the second opening and closing body 332, and the two generate a displacement. The first opening and closing body 331 is connected to the transmission member 32. Both the first opening and closing body 331 and the second opening and closing body 332 are used to connect with the rotating shaft 26 and rotate when the rotating shaft 26 rotates. The centrifugal extrusion member 34 is movably arranged in the receiving space 333, and the centrifugal extrusion member 34 can move freely in the receiving space 333. The centrifugal extrusion member 34 can also perform centrifugal motion in the receiving space 333 to extrude the transmission member 32 and force the extrusion transmission member 32 to move. When the rotational speed of the wind wheel 14 exceeds the overspeed rotational speed, the centrifugal extrusion member 34 performs centrifugal motion, driving the first opening and closing body 331 to move relative to the second opening and closing body 332, so as to drive the transmission member 32 to move and open the mechanical valve 25. By arranging the centrifugal extrusion member 34 in the receiving space 333 formed between the first opening and closing body 331 and the second opening and closing body 332 in this way, the structure is compact, the mechanical motion loss is small, the motion transmission efficiency is high, the opening efficiency of the mechanical valve 25 is improved, and the sensitivity of the centrifugal motion assembly 31 is improved.

[0058] Among them, the "first" in the first opening and closing body 331 and the "second" in the second opening and closing body 332 are used to distinguish the two opening and closing bodies, and there is no restriction on the order.

[0059] During the assembly process of the above-mentioned centrifugal motion assembly 31, first install the second opening and closing body 332, then directly place the centrifugal extrusion member 34 on the second opening and closing body 332, and then install the first opening and closing body 331. In this way, the centrifugal extrusion member 34 is placed in the receiving space 333 formed between the first opening and closing body 331 and the second opening and closing body 332, and no other connection structures are required, which is convenient for setting the centrifugal extrusion member 34.

[0060] Such as Figure 4As shown, when the rotational speed of the wind wheel 14 exceeds the overspeed rotational speed, the centrifugal extrusion member 34 generates a centrifugal motion within the accommodation space 333, and the first split body 331 can move relative to the second split body 332 away from the second split body 332, which is equivalent to forcibly supporting and opening the first split body 331 and the second split body 332 to separate the first split body 331 from the second split body 332. For example, the first split body 331 moves upward in the direction a, driving the transmission member 32 to move upward in the direction a. Alternatively, the centrifugal extrusion member 34 generates a centrifugal motion within the accommodation space 333, and the second split body 332 can move relative to the first split body 311 away from the first split body 331 to separate the second split body 332 from the first split body 331.

[0061] As Figure 5 shown, when the rotational speed of the wind wheel 14 of the valve mechanical control mechanism 30 does not exceed the overspeed rotational speed, the first split body 331 and the second split body 332 are oppositely arranged and in contact with each other.

[0062] Continue Figure 4 and Figure 5 shown, the first split body 331 and the second split body 332 are oppositely arranged in the axial direction of the rotating shaft 26, and the first split body 331 can move relative to the second split body 332 in the axial direction of the rotating shaft 26; when the centrifugal motion assembly 31 rotates around the rotating shaft 26, it can generate a centrifugal motion along the radial direction of the rotating shaft 26. Thus, when the centrifugal motion assembly 31 generates a centrifugal motion along the radial direction of the rotating shaft 26, it forces the first split body 331 to move relative to the second split body 332 in the axial direction of the rotating shaft 26, resulting in a shift in the axial direction of the rotating shaft 26 to push the transmission member 32 to shift in the axial direction of the rotating shaft 26. In this way, the centrifugal motion assembly 31 can be used to effectively force the first split body 331 to shift in the axial direction of the rotating shaft 26, improving the reliability of the first split body 331 shifting in the axial direction of the rotating shaft 26.

[0063] Among them, the first split body 331 includes a first shaft hole 3311, the second split body 332 includes a second shaft hole 3321, the first shaft hole 3311 is aligned with the second shaft hole 3321, the first shaft hole 3311 is used to sleeved outside the rotating shaft 26, and the second shaft hole 3321 is used to sleeved outside the rotating shaft 26. Thus, the rotating assembly 33 can be fixed on the rotating shaft 26 and move together with the rotating shaft 26.

[0064] Among them, the rotating shaft 26 passes through the middle part 3312 of the first split body and the middle part 3322 of the second split body, and the extending length of the rotating assembly 33 around the rotating shaft 26 is the same in one week. Thus, the balance of the rotating assembly 33 is improved, and the stability of the centrifugal motion of the centrifugal extrusion member 34 is improved.

[0065] In some embodiments, the centrifugal extrusion member 34 is a sphere. In this way, the centrifugal extrusion member 34 can roll, and the speed of the rolling motion is higher than that of the sliding motion, which is beneficial to the rapid centrifugal motion of the centrifugal extrusion member 34, improving the opening speed of the first opening and closing body 331 and the second opening and closing body 332, and then rapidly opening the mechanical valve 25 to improve the sensitivity of the valve mechanical control mechanism 30. In other embodiments, the centrifugal extrusion member 34 is in the shape of a flying saucer or a shuttle. The centrifugal extrusion member 34 can be any structure with a high middle and a low edge, which all fall within the protection scope of the embodiments of the present application, and will not be exemplified one by one here.

[0066] In some embodiments, the first opening and closing body 331 and the second opening and closing body 332 are respectively discs. In this way, it is convenient for the overall setting, with a small area and space-saving installation. Moreover, the centrifugal extrusion member 34 performs centrifugal motion along the edge of the disc without obstruction or blockage, reducing the loss of the motion of the centrifugal extrusion member 34 and being beneficial to the centrifugal motion of the centrifugal extrusion member 34. In other embodiments, the first opening and closing body 331 and the second opening and closing body 332 are respectively in the shape of a flying saucer. In still other embodiments, the first opening and closing body 331 and the second opening and closing body 332 are respectively elliptical discs. The first opening and closing body 331 and the second opening and closing body 332 can be any structure that can include a circular edge, which all fall within the protection scope of the embodiments of the present application, and will not be exemplified one by one here. In this way, it does not affect the motion of the centrifugal extrusion member 34.

[0067] Among them, the middle parts 3312 of the first opening and closing body and the middle parts 3322 of the second opening and closing body are used to connect with the rotating shaft 26. The edge 3313 of the first opening and closing body can be separated from or in contact with the edge 3323 of the second opening and closing body, and the distance between the edge 3313 of the first opening and closing body and the edge 3323 of the second opening and closing body is less than the distance between the middle parts 3312 of the first opening and closing body and the middle parts 3322 of the second opening and closing body. When the rotational speed of the wind wheel 14 in the valve mechanical control mechanism 30 exceeds the overspeed rotational speed, the centrifugal extrusion member 34 can perform centrifugal motion from the middle parts 3312 of the first opening and closing body and the middle parts 3322 of the second opening and closing body to the edge 3313 of the first opening and closing body and the edge 3323 of the second opening and closing body, forcing the edge 3313 of the first opening and closing body to be separated from the edge 3323 of the second opening and closing body. In this way, the distance between the middle parts 3312 of the first opening and closing body and the middle parts 3322 of the second opening and closing body becomes smaller to the distance between the edge 3313 of the first opening and closing body and the edge 3323 of the second opening and closing body, which is beneficial to the motion of the centrifugal extrusion member 34, and the sensitivity of the centrifugal motion assembly 31 is relatively high, so that the rotating assembly 33 moves to rotate the mechanical valve 25. Such a setting has a simple structure.

[0068] In some embodiments, a bent structure is formed from the edge 3313 of the first opening body and the edge 3323 of the second opening body to the middle part 3312 of the first opening body and the middle part 3322 of the second opening body. In other embodiments, or a curved structure is formed from the edge 3313 of the first opening body and the edge 3323 of the second opening body to the middle part 3312 of the first opening body and the middle part 3322 of the second opening body. Such a curved structure is smooth and is more conducive to the centrifugal movement of the centrifugal extrusion member 34 compared with the bent structure. Exemplarily, the curved structure is arc-shaped.

[0069] Wherein, the separation distance between the edge 3313 of the first opening body and the edge 3323 of the second opening body is smaller than the diameter of the centrifugal extrusion member 34 to ensure that the centrifugal extrusion member 34 does not break away from the rotating assembly 33 at any time, thereby improving the reliability of the rotating assembly 33.

[0070] Next, the first opening body 331 includes a first movement limiting protrusion (not shown in the figure), and the first movement limiting protrusion protrudes towards the second opening body 332 on the inner surface of the first opening body 331. The centrifugal extrusion member 34 is located between the first movement limiting protrusion and the edge 3313 of the first opening body. In this way, the starting distance of the centrifugal extrusion member 34 is short and it can be quickly extruded. And / or, the second opening body 332 includes a second movement limiting protrusion, and the second movement limiting protrusion protrudes towards the first opening body 331 on the inner surface of the second opening body 332. The centrifugal extrusion member 34 is located between the second movement limiting protrusion and the edge 3323 of the second opening body. In this way, the starting distance of the centrifugal extrusion member 34 is short and it can be quickly extruded. Exemplarily, both the first movement limiting protrusion and the second movement limiting protrusion can be annular convex columns. The first movement limiting protrusion and the second movement limiting protrusion can be annularly and respectively distributed at multiple points on the inner surface of the first opening body 331 and the inner surface of the second opening body 332, and the distance between each two points is smaller than the diameter of the spherical centrifugal extrusion member 34. In this way, it can be ensured that the centrifugal extrusion member 34 performs centrifugal movement within the restricted movement area.

[0071] Next Figure 4 and Figure 5 As shown, the first opening body 331 includes a first main body portion 3314 and a first side portion 3316 connected to the edge 3315 of the first main body portion. The first main body portion 3314 is used to connect to the rotating shaft 26, and the first side portion 3316 extends obliquely from the first main body portion 3314 towards the edge 3313 of the first opening body and towards the second opening body 332. In this way, the centrifugal extrusion member 34 performs centrifugal movement along the first side portion 3316 from the first main body portion 3314 to the obliquely transitioning first side portion 3316. The entire centrifugal movement is unobstructed and undisturbed, which is more conducive to the centrifugal extrusion member 34 quickly reaching the edge 3313 of the first opening body to extrude the edge 3313 of the first opening body.

[0072] Continuing asFigure 4 and Figure 5 As shown in Figure 5 , the second opening and closing body 332 includes a second main body portion 3324 and a second side portion 3326 connected to the edge 3325 of the second main body portion. The second main body portion 3324 is used to connect with the rotating shaft 26, and the second side portion 3326 extends obliquely from the second main body portion 3324 in the direction of the edge 3323 of the second opening and closing body 332 and in the direction close to the first opening and closing body 331. In this way, the centrifugal extrusion member 34 moves centrifugally along the second side portion 3326 of the second main body portion 3324 to the obliquely transitioning second side portion 3326. The entire centrifugal movement is unobstructed and undisturbed, which is more conducive to the centrifugal extrusion member 34 quickly reaching the edge 3323 of the second opening and closing body to extrude the edge 3323 of the second opening and closing body.

[0073] In the embodiment as shown in Figure 4 and Figure 5 the valve mechanical control mechanism 30 includes an elastic member 41. The elastic member 41 can buffer the force generated when the first opening and closing body 331 moves relative to the second opening and closing body 332. The elastic member 41 abuts against the first opening and closing body 331 and is used to provide an elastic force in the opposite direction of the movement of the first opening and closing body 331 relative to the second opening and closing body 332. In this way, the elastic member 41 can buffer the force generated when the first opening and closing body 331 moves relative to the second opening and closing body 332, avoiding the force that suddenly breaks open the rotating assembly 33 by the centrifugal extrusion member 34 and causing damage to other components. In some other embodiments, the elastic member 41 is connected inside the rotating assembly 33 and abuts against the inner surface of the first opening and closing body 331 and the inner surface of the second opening and closing body 332. This elastic member 41 can be elongated to form a pre-tightening force for the first opening and closing body 331 and the second opening and closing body 332 to contact. The first opening and closing body 331 moves relative to the second opening and closing body 332 in the direction of the elongation of the elastic member 41 and separates.

[0074] Exemplarily, the elastic member 41 can be a spring, but is not limited thereto. The elastic member 41 can also be an elastic rubber member.

[0075] Continuing Figure 4 and Figure 5 As shown in Figure 5 , the valve mechanical control mechanism 30 includes a first limiting member 42 located on the side of the first opening and closing body 331 facing away from the second opening and closing body 332. The first limiting member 42 is used to be fixedly connected to the rotating shaft 26, and the elastic member 41 elastically abuts between the first opening and closing body 331 and the first limiting member 42. In this way, the first limiting member 42 can limit the separation degree of the first opening and closing body 331 relative to the first limiting member 42. At the same time, the elastic member 41 buffers the force generated during the process of the first opening and closing body 331 moving away from the second opening and closing body 332, improving the reliability of the movement of the first opening and closing body 331 relative to the second opening and closing body 332, so that the transmission member 32 gradually opens the mechanical valve 25.

[0076] Among them, the first limiting member 42 can be a circular ring. The first limiting member 42 can be a cube, and the cube is arranged in the shaft hole for installing the rotating shaft 26. The first limiting member 42 can be a cuboid, and the cuboid is arranged in the shaft hole for installing the rotating shaft 26. Any structure whose cross-sectional area of the first limiting member 42 is larger than that of the elastic member 41 belongs to the protection scope of the embodiments of the present application.

[0077] In some embodiments, the distance between the first limiting member 42 and the outer surface of the first opening and closing body 331 is less than the original length of the elastic member 41. In this way, the elastic member 41 is located on the outer surface of the first opening and closing body 331 and applies a force in the direction towards the first opening and closing body 331 to form a pre-tightening force, so that the first opening and closing body 331 and the second opening and closing body 332 are more stable when they are in contact. In this case, the force exerted by the centrifugal squeezing member 34 on the first opening and closing body 331 and the second opening and closing body 332 is greater than the pre-tightening force of the first opening and closing body 331 and the second opening and closing body 332, and the elastic member 41 is compressed in the direction away from the first opening and closing body 331 to separate the first opening and closing body 331 and the second opening and closing body 332. In some other embodiments, the distance between the first limiting member 42 and the outer surface of the first opening and closing body 331 is equal to the original length of the elastic member 41. In this case, the centrifugal squeezing member 34 only needs to squeeze the first opening and closing body 331 and the second opening and closing body 332 to quickly separate the first opening and closing body 331 and the second opening and closing body 332.

[0078] Continue Figure 4 and Figure 5 As shown, the valve mechanical control mechanism 30 includes a second limiting member 43 for fixedly connecting with the rotating shaft 26. The second limiting member 43 is located on the side of the second opening and closing body 332 away from the first opening and closing body 331. In this way, the second limiting member 43 can limit the movement of the second opening and closing body 332 and improve the stability of the second opening and closing body 332. Among them, the structure of the second limiting member 43 can be the same as that of the first limiting member 42. Details are not described herein again.

[0079] Then Figure 4 and Figure 5 As shown, the transmission member 32 includes a transmission connection end 321. The transmission member 32 can form a supporting force, and the transmission connection end 321 of the transmission member 32 can be driven by the centrifugal motion assembly 31 for the transmission member 32. The transmission connection end 321 is in contact with the centrifugal motion assembly 31. When the centrifugal motion assembly 31 rotates with the rotating shaft 26, it rotates relative to the transmission connection end 321. In this way, by transmitting the force through the transmission connection end 321, it is more conducive to concentrating the transmission force and improving the reliability of the movement of the transmission member 32.

[0080] In some embodiments, the transmission connection end 321 is spherical. In this way, the contact surface with the centrifugal motion component 31 is small, the pressure is greater, which is more conducive to the transmission of the transmission member 32. In some other embodiments, the transmission connection end 321 is cylindrical. Exemplarily, the transmission member 32 may be a connecting rod. The transmission connection end 321 is the end of the connecting rod close to the contact with the centrifugal motion component 31. In this way, using a connecting rod, the structure is simple, the installation is convenient, the cost is low, and the contact surface between the transmission connection end 321 and the centrifugal motion component 31 is small, the pressure is greater, which is more conducive to the transmission of the connecting rod. The transmission member 32 may be a rotating shaft. It is not limited herein.

[0081] The foregoing are only the preferred embodiments of the present application and are not intended to limit the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present application shall be included within the scope of protection of the present application.

Claims

1. A pitch control system is applied to the wind turbine rotor, characterized in that, the pitch control system includes: a pitch cylinder for connecting with the wind turbine rotor; an oil circuit connected to the pitch cylinder; a mechanical valve connected to the oil circuit for controlling the opening or closing of the oil circuit. When the rotational speed of the wind turbine rotor does not exceed the overspeed rotational speed, the mechanical valve is closed; and, a valve mechanical control mechanism connected to the mechanical valve; the valve mechanical control mechanism includes a centrifugal motion component and a transmission member. The transmission member is respectively connected to the centrifugal motion component and the mechanical valve, and the centrifugal motion component is used for connecting with the rotating shaft of the wind turbine rotor; the centrifugal motion component includes a rotating component and a centrifugal extrusion member; the rotating component is used for connecting with the rotating shaft. The rotating component includes a first opening and closing body and a second opening and closing body arranged oppositely. An accommodation space is formed between the first opening and closing body and the second opening and closing body. The first opening and closing body can move relative to the second opening and closing body. The first opening and closing body is connected to the transmission member. Both the first opening and closing body and the second opening and closing body are used for connecting with the rotating shaft and rotate when the rotating shaft rotates; the centrifugal extrusion member is movably arranged in the accommodation space. When the rotating shaft rotates and the rotational speed of the wind turbine rotor exceeds the overspeed rotational speed, the centrifugal extrusion member performs centrifugal motion in the accommodation space, forcing the transmission member to move, squeezing the first opening and closing body to move relative to the second opening and closing body away from the second opening and closing body, so as to forcibly support and open the first opening and closing body and the second opening and closing body, driving the transmission member to move relative to the mechanical valve and triggering the mechanical valve to open.

2. The pitch control system according to claim 1, characterized in that, the first opening and closing body and the second opening and closing body are arranged oppositely in the axial direction of the rotating shaft, and the first opening and closing body can move relative to the second opening and closing body in the axial direction of the rotating shaft.

3. The pitch control system according to claim 1, characterized in that, the centrifugal extrusion member is a sphere.

4. The pitch control system according to claim 1, characterized in that, the first opening and closing body and the second opening and closing body are respectively discs.

5. The pitch control system according to claim 3, characterized in that, the middle parts of the first opening and closing body and the second opening and closing body are used for connecting with the rotating shaft; the distance between the edge of the first opening and closing body and the edge of the second opening and closing body is less than the distance between the middle parts of the first opening and closing body and the second opening and closing body.

6. The pitch control system according to claim 5, characterized in that, the first opening and closing body includes a first main body part and a first edge part connected to the edge of the first main body part. The first main body part is used for connecting with the rotating shaft, and the first edge part extends obliquely from the first main body part in the direction of the edge of the first opening and closing body and towards the second opening and closing body; and / or, The second opening and closing body includes a second main body portion and a second side portion connected to the edge of the second main body portion. The second main body portion is used for connecting to the rotating shaft, and the second side portion extends obliquely from the second main body portion in the direction of the edge of the second opening and closing body and towards the first opening and closing body.

7. The pitch control system according to claim 3, wherein, the valve mechanical control mechanism includes an elastic member, and the elastic member abuts against the first opening and closing body for providing an elastic force in the opposite direction of the movement of the first opening and closing body relative to the second opening and closing body.

8. The pitch control system according to claim 7, wherein, the valve mechanical control mechanism includes a first limiting member located on the side of the first opening and closing body facing away from the second opening and closing body. The first limiting member is used for fixedly connecting to the rotating shaft, and the elastic member elastically abuts between the first opening and closing body and the first limiting member; and / or, the valve mechanical control mechanism includes a second limiting member for fixedly connecting to the rotating shaft, and the second limiting member is located on the side of the second opening and closing body facing away from the first opening and closing body.

9. The pitch control system according to claim 2, wherein, the transmission member includes a transmission connection end, and the transmission connection end contacts the centrifugal movement assembly. When the centrifugal movement assembly rotates with the rotating shaft, it rotates relative to the transmission connection end.

10. The pitch control system according to claim 9, wherein, the transmission member is a connecting rod, and the transmission connection end is the end of the connecting rod close to contacting the centrifugal movement assembly.

11. The pitch control system according to claim 1, wherein, the pitch control system includes an electric control valve and an electric control mechanism connected to the electric control valve. The electric control valve is connected to the oil circuit.

12. A wind turbine, wherein, the wind turbine includes: a tower; a nacelle installed on the tower; a wind wheel assembled in the nacelle; the pitch control system according to any one of claims 1-11, disposed in the nacelle and connected to the wind wheel.

Images