Hydraulic variable pitch system and wind turbine generator

Abstract

The invention discloses a hydraulic variable pitch system and a wind turbine generator set, and relates to the technical field of wind turbine variable pitch, the hydraulic variable pitch system comprises a hub and a hydraulic device, the hydraulic device is arranged in the hub, the hydraulic device comprises an oil cylinder used for driving blades to move and an oil tank used for storing hydraulic oil, the oil cylinder is connected with the oil tank through a communicating pipeline, and the oil tank is connected with the hub. A valve set and a hydraulic driving device are arranged on the communicating pipeline and used for controlling flowing of hydraulic oil in the communicating pipeline, the valve set and the hydraulic driving device are both installed on the oil cylinder, and the hydraulic device is arranged in the hub, so that on one hand, an oil-electricity sliding ring can be omitted, faults of the oil-electricity sliding ring can be avoided, and the cost of the hydraulic variable-pitch system can be reduced; and on the other hand, pipelines in a cabin can be omitted, leakage points of the pipelines can be reduced, meanwhile, the valve set can be integrated on the oil tank conveniently, the length of the pipelines can be further reduced, and therefore the problems that the cost of the hydraulic variable-pitch system is high, and the risk of oil leakage is likely to occur are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of wind power pitch control, and in particular to a hydraulic pitch control system and a wind turbine generator set. Background Art

[0002] The hydraulic pitch system is an important device used to control the blade angle (i.e. pitch angle) in wind turbines. By adjusting the blade angle, the force of wind on the blade can be changed, thereby controlling the speed and power output of the wind turbine. This is crucial for optimizing power generation efficiency, protecting equipment from overload, and quickly shutting down in an emergency.

[0003] At present, the hydraulic pitch control system in the wind turbine is usually dispersedly arranged in the hub and the nacelle, and needs to be connected to the oil-electric slip ring through pipes, which takes up a large space, has long pipelines and many pipe joints, resulting in a high cost of the hydraulic pitch control system, and is prone to loosening or sealing failure, making the pipeline prone to the risk of oil leakage. Summary of the invention

[0004] The main purpose of the present invention is to provide a hydraulic pitch control system and a wind turbine generator set, aiming to solve the problem that the hydraulic pitch control system is high in cost and prone to oil leakage risk.

[0005] To achieve the above object, the hydraulic pitch system proposed in the present invention is used for a wind turbine generator set, and the hydraulic pitch system comprises:

[0006] Wheel hub; and

[0007] A hydraulic device is arranged in the wheel hub, and the hydraulic device includes a cylinder for driving the blades to move, and an oil tank for storing hydraulic oil. The cylinder is connected to the oil tank through a connecting pipeline. A valve group and a hydraulic drive device are provided on the connecting pipeline to control the flow of hydraulic oil in the connecting pipeline, and the valve group and the hydraulic drive device are both installed on the oil tank.

[0008] In one embodiment, the hydraulic device further comprises an accumulator disposed in the communicating pipeline, wherein the accumulator is mounted on the oil cylinder; and / or,

[0009] The oil tank is mounted on the oil cylinder.

[0010] In one embodiment, the oil tank and the accumulator are respectively arranged on both sides of the oil cylinder.

[0011] In one embodiment, the hydraulic pitch system further includes a bearing body, the bearing body is provided with a first accommodating chamber, a second accommodating chamber, a third accommodating chamber and a connecting passage, the hydraulic drive device and the valve group are arranged in the first accommodating chamber, the oil tank is arranged in the second accommodating chamber, the oil cylinder is arranged in the third accommodating chamber, and the connecting passage connects the first accommodating chamber, the second accommodating chamber and the third accommodating chamber;

[0012] Wherein, the connecting pipeline includes a connecting channel.

[0013] In one embodiment, the bearing body is further provided with a fourth accommodating cavity, and the connecting passage is connected with the fourth accommodating cavity;

[0014] The hydraulic device further includes an accumulator, which is disposed in the fourth accommodating chamber.

[0015] In one embodiment, the wheel hub includes a wheel hub body and a connecting sleeve disposed on the wheel hub body, and the connecting sleeve rotates synchronously with the wheel hub body.

[0016] In one embodiment, the oil tank is arranged in the connecting sleeve; and / or,

[0017] The hydraulic pitch system further includes an accumulator, which is disposed in the connecting sleeve.

[0018] In one embodiment, the connecting sleeve includes an outer cylinder and an inner cylinder rotatably mounted in the outer cylinder, the outer cylinder is used to connect to a nacelle or a gear box, and the inner cylinder is connected to the hub body.

[0019] In one embodiment, the hydraulic pitch system further includes a first driving power source disposed in the hub, and the first driving power source is electrically connected to the hydraulic driving device.

[0020] The present invention further proposes a wind turbine generator set, comprising a hub and a hydraulic pitch system arranged in the hub, wherein the hydraulic pitch system comprises the above-mentioned hydraulic pitch system, and the hydraulic pitch system comprises:

[0021] Wheel hub; and

[0022] A hydraulic device is arranged in the wheel hub, and the hydraulic device includes a cylinder for driving the blades to move, and an oil tank for storing hydraulic oil. The cylinder is connected to the oil tank through a connecting pipeline. A valve group and a hydraulic drive device are provided on the connecting pipeline to control the flow of hydraulic oil in the connecting pipeline, and the valve group and the hydraulic drive device are both installed on the oil tank.

[0023] In the technical solution of the present invention, by arranging the hydraulic device in the wheel hub, on the one hand, the oil-electric slip ring can be eliminated, which can avoid the failure of the oil-electric slip ring, reduce the failure rate of the hydraulic pitch system, and reduce the cost of the hydraulic pitch system. On the other hand, the pipelines in the cabin can be eliminated, and the length of the connecting pipeline and the number of pipe joints can be reduced, which is beneficial to reducing the leakage points of the pipeline. At the same time, it is also convenient to integrate the valve group on the oil tank, improve the integration of the hydraulic pitch system, and help to further reduce the length of the pipeline, which helps to reduce the failure rate of the hydraulic pitch system and reduce the cost of the hydraulic pitch system, thereby solving the problem of high cost and easy risk of oil leakage of the hydraulic pitch system. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] 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 or the description of the prior art 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 the structures shown in these drawings without paying creative work.

[0025] Figure 1 A schematic structural diagram of an embodiment of a hydraulic pitch control system provided by the present invention;

[0026] Figure 2 A structural block diagram of an embodiment of the hydraulic device provided by the present invention;

[0027] Figure 3 A structural block diagram of another embodiment of the hydraulic device provided by the present invention;

[0028] Figure 4 A structural block diagram of another embodiment of the hydraulic device provided by the present invention;

[0029] Figure 5 A schematic structural diagram of an embodiment of a connecting sleeve provided by the present invention;

[0030] Figure 6 A schematic structural diagram of another embodiment of the connecting sleeve provided by the present invention.

[0031] Description of Figure Numbers:

[0032] 100. Hydraulic pitch system; 1. Hub; 2. Hydraulic device; 21. Cylinder; 22. Oil tank; 23. Valve group; 24. Hydraulic drive device; 241. Hydraulic pump; 242. Drive motor; 25. Accumulator; 3. Carrying body; 31. First accommodating chamber; 311. First accommodating sub-chamber; 312. First accommodating sub-chamber; 32. Second accommodating chamber; 33. Third accommodating chamber; 34. Fourth accommodating chamber; 4. Connecting sleeve; 41. Outer cylinder; 42. Inner cylinder.

[0033] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0034] 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.

[0035] It should be noted that if the embodiments of the present invention involve directional indications (such as up, down, left, right, front, back, etc.), the directional indications are only used to explain the relative position relationship, movement status, etc. between the components in a certain specific posture. If the specific posture changes, the directional indication will also change accordingly.

[0036] In addition, if there are descriptions involving "first", "second", etc. in the embodiments of the present invention, the descriptions of "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of technical features indicated. Therefore, the features limited to "first" and "second" may explicitly or implicitly include at least one of the features. In addition, if "and / or" or "and / or" appears in the full text, its meaning includes three parallel solutions. Taking "A and / or B" as an example, it includes solution A, solution B, or solutions that satisfy both A and B. In addition, the technical solutions between the various embodiments can be combined with each other, but it must be based on the ability of ordinary technicians in this field to implement. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0037] The hydraulic pitch system is an important device used to control the blade angle (i.e. pitch angle) in wind turbines. By adjusting the blade angle, the force of wind on the blade can be changed, thereby controlling the speed and power output of the wind turbine. This is crucial for optimizing power generation efficiency, protecting equipment from overload, and quickly shutting down in an emergency.

[0038] At present, the hydraulic pitch control system in the wind turbine usually includes an oil cylinder, an oil tank, a valve group and a hydraulic drive device, among which the oil cylinder and the valve group are generally arranged in the wheel hub, and the oil tank and the hydraulic drive device are generally arranged in the nacelle and connected by pipelines. However, due to the relative movement between the nacelle and the wheel hub, an oil-electric slip ring for dynamic and static conversion of oil and electrical signals and a matching pipeline layout are required. On the one hand, the oil-electric slip ring is expensive and prone to leakage. On the other hand, the pipeline is laid for a long time, which makes it inevitable that the pipeline will be entangled or overlapped in space. At the same time, the pipeline in the wheel hub may loosen or bend as the wheel hub rotates, resulting in the risk of oil leakage in the pipeline.

[0039] Based on this, the present invention proposes a hydraulic pitch system for a wind turbine, aiming to solve the problem that the hydraulic pitch system is high in cost and prone to oil leakage. Figures 1 to 5 This is a schematic structural diagram of the hydraulic variable pitch system provided by the present invention.

[0040] See also Figures 1 to 5 In one embodiment of the present invention, the hydraulic pitch system 100 includes a hub 1 and a hydraulic device 2, wherein the hydraulic device 2 is arranged in the hub 1, and the hydraulic device 2 includes an oil cylinder 21 for driving the blade movement, and an oil tank 22 for storing hydraulic oil, wherein the oil cylinder 21 is connected to the oil tank 22 via a connecting pipeline, and a valve group 23 and a hydraulic driving device 24 are provided on the connecting pipeline to control the flow of hydraulic oil in the connecting pipeline, and the valve group 23 and the hydraulic driving device 24 are both installed on the oil cylinder 21.

[0041] In the technical solution of the present invention, by arranging the hydraulic device 2 in the hub 1, on the one hand, the oil-electric slip ring can be eliminated, which can avoid the failure of the oil-electric slip ring, reduce the failure rate of the hydraulic pitch system 100, and reduce the cost of the hydraulic pitch system 100. On the other hand, the pipelines in the cabin can be eliminated, and the length of the connecting pipeline and the number of pipe joints can be reduced, which is beneficial to reducing the leakage points of the pipeline. At the same time, it is also convenient to integrate the valve group 23 on the oil tank 22, improve the integration of the hydraulic pitch system 100, and help to further reduce the length of the pipeline, which is helpful to reduce the failure rate of the hydraulic pitch system 100 and reduce the cost of the hydraulic pitch system 100, thereby solving the problem that the cost of the hydraulic pitch system 100 is high and prone to oil leakage.

[0042] It can be understood that the hydraulic drive device 24 includes a hydraulic pump 241 and a drive motor 242. The hydraulic pump 241 is arranged on the communication pipeline to drive the hydraulic oil in the communication pipeline to flow, and the drive motor 242 drives the connected hydraulic pump 241 to drive the hydraulic pump 241 to work. The hydraulic pump 241 and the drive motor 242 are integrated together to improve the integration of the hydraulic drive device 24.

[0043] In one embodiment, see Figure 3 The hydraulic drive device 24 and the valve group 23 are respectively arranged at the two ends of the oil tank 22. On the one hand, arranging the hydraulic drive device 24 outside the oil tank 22 is beneficial to reducing the requirements of the hydraulic drive device 24, so as to reduce the cost of the hydraulic drive device 24. On the other hand, the weight of the hydraulic drive device 24 and the valve group 23 can be evenly distributed to avoid local overweight, thereby facilitating the integrated hydraulic drive device 24, the valve group 23 and the oil tank 22 to be arranged in the wheel hub 1.

[0044] In another embodiment, see Figure 2 The hydraulic drive device 24 is arranged in the oil tank 22, so that the space of the oil tank 22 can be used to set the hydraulic drive device 24, which is beneficial to reducing the space occupied by the hydraulic device 2 and improving the space utilization rate of the hydraulic device 2, thereby helping to reduce the volume after integration.

[0045] It should be noted that there are various ways to connect the valve group 23 to the oil tank 22. The valve group 23 can be installed on the oil tank 22 through a screw structure, or can be installed on the oil tank 22 through welding, or can be installed on the oil tank 22 through a band, etc. The present invention does not limit this. Similarly, there are various ways to connect the hydraulic drive device 24 to the oil tank 22. The hydraulic drive device 24 can be installed on the oil tank 22 through a screw structure, or can be installed on the oil tank 22 through welding, or can be installed on the oil tank 22 through a band, etc. The present invention does not limit this.

[0046] It should be noted that, in order to enable the oil tank 22 to rotate with the wheel hub 1, the oil tank 22 includes a supercharged oil tank 22. Thus, by using the supercharged oil tank 22, the oil level in the oil tank 22 can maintain a certain residual pressure to prevent oil return when the wheel hub 1 rotates. It is understandable that there are many types of supercharged oil tanks 22. For example, the supercharged oil tank 22 can be a bleed air supercharged oil tank 22 or a self-supercharged oil tank 22, and the present invention does not limit this.

[0047] In one embodiment of the present invention, see Figures 2 to 3The hydraulic pitch system 100 includes an accumulator 25 provided in the connecting pipeline, and the accumulator 25 is installed in the oil cylinder 21. In this way, the accumulator 25 is provided to provide power so that the hydraulic pitch system 100 can be urgently aligned. It can be understood that there are many types of accumulators 25, for example, it can be an airbag accumulator 25, a piston accumulator 25, a diaphragm accumulator 25, etc., and the present invention does not limit this.

[0048] In one embodiment, the oil tank 22 is installed on the oil tank 22, so as to integrate the oil tank 22, the valve group 23 and the hydraulic drive device 24 with the oil cylinder 21, thereby improving the integration of the hydraulic pitch system 100, facilitating the overall installation in the hub 1, and reducing the length of the pipeline, which helps to reduce costs and failure rates. Of course, in other embodiments, the oil cylinder 21 and the oil tank 22 can also be dispersedly arranged in the hub 1, and the present invention is not limited thereto. Furthermore, there are many ways to connect the oil tank 22 to the oil cylinder 21. The oil tank 22 can be installed on the oil tank 22 by a screw structure, can be installed on the oil tank 22 by welding, can be installed on the oil tank 22 by a hoop, etc., and the present invention is not limited thereto.

[0049] It should be noted that the above two related technical features: "The hydraulic pitch system 100 includes an accumulator 25 arranged in the connecting pipeline, and the accumulator 25 is installed on the oil cylinder 21", and "The oil tank 22 is installed on the oil tank 22" can be set either one or at the same time. Obviously, setting them at the same time will have a better effect.

[0050] There are many ways to arrange the accumulator 25 and the oil tank 22 on the oil cylinder 21. The accumulator 25 and the oil tank 22 can be arranged on the same side of the oil cylinder 21, or on both sides of the oil cylinder 21, etc. The present invention does not limit this. Specifically, in this embodiment, please refer to Figure 2 and Figure 3 The oil tank 22 and the accumulator 25 are respectively arranged on both sides of the oil cylinder 21, so that the weight of the oil tank 22, the accumulator 25 and the oil cylinder 21 can be evenly distributed to avoid local overweight, thereby facilitating the integrated arrangement of the oil tank 22, the accumulator 25 and the oil cylinder 21 in the wheel hub 1.

[0051] In one embodiment, see Figure 4The hydraulic pitch system 100 also includes a bearing body 3, the bearing body 3 is provided with a first accommodating chamber 31, a second accommodating chamber 32, a third accommodating chamber 33 and a connecting passage, the hydraulic drive device 24 and the valve group 23 are arranged in the first accommodating chamber 31, the oil tank 22 is arranged in the second accommodating chamber 32, the oil cylinder 21 is arranged in the third accommodating chamber 33, and the connecting passage connects the first accommodating chamber 31, the second accommodating chamber 32 and the third accommodating chamber 33, wherein the connecting pipeline includes a connecting passage, so that the first accommodating chamber 31, the second accommodating chamber 32 and the third accommodating chamber 33 are arranged by setting the bearing body 3, and the first accommodating chamber is arranged by setting the first accommodating chamber 31, the second accommodating chamber 32 and the third accommodating chamber 33, so as to integrate the hydraulic drive device 24, the valve group 23, the oil cylinder 21 and the oil tank 22 in the bearing body 3, and directly use the connecting channel as the connecting pipeline to connect the first accommodating chamber 31, the second accommodating chamber 32 and the third accommodating chamber 33, so as to omit external pipelines and corresponding sealing rings, reduce the risks of loose pipe joints and pipeline leakage, and can greatly reduce the replacement and maintenance costs of rubber parts and their aging, so that the hydraulic device 2 can be modularly packaged, so that the hydraulic device 2 can form an integral part, which is beneficial to reduce the volume and weight of the hydraulic device 2 and facilitate integrated replacement.

[0052] It should be noted that the first accommodating chamber 31 includes a first accommodating sub-chamber 311312 and a second accommodating sub-chamber which are connected to each other, wherein the first hydraulic drive device 24 is arranged in the first accommodating sub-chamber 311312, and the valve group 23 is arranged in the second accommodating sub-chamber. In this way, by setting the first accommodating sub-chamber 311312 and the second accommodating sub-chamber, the first accommodating sub-chamber 311312 and the second accommodating sub-chamber can be respectively adapted to the hydraulic drive device 24 and the valve group 23, so as to reduce the size of the first accommodating sub-chamber 311312 and the second accommodating sub-chamber, thereby helping to reduce the volume of the carrying body 3.

[0053] In one embodiment, the bearing body 3 includes a plurality of bearing parts, and the plurality of bearing parts can be spliced ​​together to form the first accommodating chamber 31, the second accommodating chamber 32, the third accommodating chamber 33 and the communicating passage. In this way, a split arrangement is adopted so that the hydraulic drive device 24, the valve group 23, the oil cylinder 21 and the oil tank 22 are respectively installed in the first accommodating chamber 31, the second accommodating chamber 32 and the third accommodating chamber 33. Further, there are many ways to connect the bearing parts, for example, the bearing parts can be spliced ​​together by welding, or spliced ​​together by bolts, etc. As long as the bearing parts can be spliced ​​together, the present invention is not limited to this.

[0054] For further information, see Figure 4 The bearing body 3 is also provided with a fourth accommodating chamber 34, and the connecting passage is connected to the fourth accommodating chamber 34. The hydraulic device 2 also includes an accumulator 25, and the accumulator 25 is arranged in the fourth accommodating chamber 34. In this way, by providing the fourth accommodating chamber 34 to accommodate the accumulator 25, the accumulator 25 is integrated in the bearing body 3, thereby helping to improve the integration of the bearing body 3.

[0055] As the megawatt of wind turbines increases in the future, the size and number of accumulators 25 and the size and number of oil cylinders 21 may increase, but the space in the hub 1 is limited. Therefore, in this embodiment, please refer to Figure 5 The wheel hub 1 includes a wheel hub 1 body and a connecting sleeve 4 provided on the wheel hub 1 body, and the connecting sleeve 4 rotates synchronously with the wheel hub 1 body. Thus, the connecting sleeve 4 is provided to increase the installation space of the wheel hub 1, so that the hydraulic device 2 can be completely installed in the wheel hub 1. Furthermore, there are many ways to connect the wheel hub 1 body and the connecting sleeve 4. The connecting sleeve 4 can be connected to the wheel hub 1 body by flange or by welding, and the present invention does not limit this.

[0056] In one embodiment, the oil tank 22 is disposed in the connecting sleeve 4. In this way, the oil tank 22 is disposed in the connecting sleeve 4 so that the oil tank 22 can rotate synchronously with the hub 1, thereby eliminating the oil-electric slip ring and reducing the cost of the hydraulic pitch system 100.

[0057] In one embodiment, the hydraulic pitch system 100 also includes an accumulator 25, and the accumulator 25 is arranged in the connecting sleeve 4. In this way, the accumulator 25 is arranged in the connecting sleeve 4 to save space in the main body of the hub 1, so that the hydraulic drive device 24 and the valve group 23 can be arranged in the main body, so that the hub 1 can be equipped with a larger size of the hydraulic device 2.

[0058] It should be noted that the above two related technical features: "the oil tank 22 is arranged in the connecting sleeve 4" and "the hydraulic pitch system 100 also includes an accumulator 25, and the accumulator 25 is arranged in the connecting sleeve 4" can be set either one or at the same time, and the present invention does not limit this.

[0059] In one embodiment of the present invention, see Figure 5 The connecting sleeve 4 includes an outer cylinder 41 and an inner cylinder 42 rotatably installed in the outer cylinder 41, the outer cylinder 41 is used to connect to the engine room or the gear box, and the inner cylinder 42 is connected to the hub 1 body. In this way, by arranging the outer cylinder 41 and the inner cylinder 42, one end of the connecting sleeve can be connected to the engine room or the gear box, and the other end can be connected to the hub 1 body, so that the connecting sleeve 4 can rotate synchronously with the hub 1 body, and the two ends of the connecting sleeve 4 can be supported on the engine room or the gear box and the hub 1 body, so as to prevent the connecting sleeve 4 from being suspended on the hub 1 body, which is beneficial to keep the connecting sleeve 4 balanced.

[0060] In one embodiment, the hydraulic pitch system 100 also includes a first driving power supply arranged in the hub 1, and the first driving power supply is electrically connected to the hydraulic drive device 24. In this way, by setting the first driving power supply, the power of the hydraulic drive device 24 can be increased when the hydraulic pitch system 100 is in emergency pitching, so that the blades can move quickly.

[0061] The present invention also proposes a wind turbine generator set, which includes a hydraulic pitch system 100. The specific structure of the hydraulic pitch system 100 refers to the above-mentioned embodiment. Since the wind turbine generator set adopts all the technical solutions of all the above-mentioned embodiments, it has at least all the beneficial effects brought by the technical solutions of the above-mentioned embodiments, which will not be described one by one here.

[0062] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A hydraulic pitch system for a wind turbine, characterized in that: The hydraulic pitch system comprises: Wheel hub; and A hydraulic device is arranged in the wheel hub, and the hydraulic device includes a cylinder for driving the blades to move, and an oil tank for storing hydraulic oil. The cylinder is connected to the oil tank through a connecting pipeline. A valve group and a hydraulic drive device are provided on the connecting pipeline to control the flow of hydraulic oil in the connecting pipeline, and the valve group and the hydraulic drive device are both installed on the oil tank.

2. The hydraulic pitch system according to claim 1, characterized in that: The hydraulic device further comprises an accumulator provided in the communicating pipeline, wherein the accumulator is installed in the oil cylinder; and / or, The oil tank is mounted on the oil cylinder.

3. The hydraulic pitch system according to claim 2, characterized in that: The oil tank and the accumulator are respectively arranged on both sides of the oil cylinder.

4. The hydraulic pitch system according to claim 1, characterized in that: The hydraulic pitch system further includes a bearing body, the bearing body is provided with a first accommodating chamber, a second accommodating chamber, a third accommodating chamber and a connecting passage, the hydraulic drive device and the valve group are arranged in the first accommodating chamber, the oil tank is arranged in the second accommodating chamber, the oil cylinder is arranged in the third accommodating chamber, and the connecting passage connects the first accommodating chamber, the second accommodating chamber and the third accommodating chamber; Wherein, the connecting pipeline includes a connecting channel.

5. The hydraulic pitch system according to claim 4, characterized in that: The bearing body is further provided with a fourth accommodating cavity, and the communicating passage is connected with the fourth accommodating cavity; The hydraulic device further includes an accumulator, which is disposed in the fourth accommodating chamber.

6. The hydraulic pitch system according to claim 1, characterized in that: The wheel hub comprises a wheel hub body and a connecting sleeve arranged on the wheel hub body, and the connecting sleeve rotates synchronously with the wheel hub body.

7. The hydraulic pitch system according to claim 6, characterized in that: The oil tank is arranged in the connecting sleeve; and / or, The hydraulic pitch system further includes an accumulator, which is disposed in the connecting sleeve.

8. The hydraulic pitch system according to claim 6, characterized in that: The connecting sleeve comprises an outer cylinder and an inner cylinder rotatably mounted in the outer cylinder, the outer cylinder is used to connect to a cabin or a gear box, and the inner cylinder is connected to the hub body.

9. The hydraulic pitch system according to claim 1, characterized in that: The hydraulic pitch system further includes a first driving power source disposed in the wheel hub, and the first driving power source is electrically connected to the hydraulic driving device.

10. A wind turbine generator set, characterized in that: It comprises a wheel hub and a hydraulic pitch system arranged in the wheel hub, wherein the hydraulic pitch system comprises the hydraulic pitch system according to any one of claims 1 to 9.

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