Wind turbine variable pitch transmission system and wind turbine generator system

Abstract

The embodiment of the application provides a wind turbine variable pitch transmission system and a wind turbine, and relates to the field of wind power generation. The embodiment aims to improve the problem that wear is easily generated between a variable pitch bearing and a variable pitch speed reducer, and the problem that the service life of a variable pitch system and the reliability of the wind turbine are affected. The wind turbine variable pitch transmission system comprises a hub, a variable pitch motor, a variable pitch speed reducer, a variable pitch bearing, a blade flange, a blade and a brake assembly. The brake assembly comprises a mechanical brake and / or a hydraulic brake. The mechanical brake is arranged between the hub and the blade flange, and the mechanical brake is arranged in damping contact with the blade flange. The hydraulic brake is arranged between the hub and the blade flange, and the hydraulic brake is arranged in damping contact with the blade flange. The brake assembly realizes the braking of the output end, and solves the problem that the motor braking force of the input end is transmitted to the blade with a delay and the phenomenon that the blade cannot inhibit the torque generated by the weight and the wind load.

Description

Technical Field

[0001] This invention relates to the field of wind power generation, and more specifically, to a wind turbine pitch transmission system and a wind turbine generator set. Background Technology

[0002] The existing pitch control system of wind turbine generators mainly consists of a hub, pitch motor, pitch reducer, pitch bearing, blade flange, and blades. The pitch motor drives the reducer to rotate the blades, thus achieving pitch control. The pitch motor is equipped with a power-off brake, which applies braking when the turbine is stopped, but not when it is not stopped. During the pitch-control phase, braking is provided by the motor output. Since the braking end is located on the motor drive end, it has the following disadvantages.

[0003] 1. Due to the presence of backlash, there is a meshing gap between the gear ring connecting the blade and the drive gear. This gap is amplified by the reducer, and the cumulative gap in the transmission system can reach 300° (the reducer output end is fixed while the reducer input end rotates). The output force from the motor end is delayed when it is transmitted to the blade through the reducer, the reducer output teeth and the gear ring. However, the force generated by the wind load and weight on the blade acts directly on the pitch bearing gear ring without any delay t. Assuming the bearing friction force is M1 and the torque transmitted from the blade by gravity and external load is M2, when M2 > M1, the blade will rotate with the bearing gear ring, i.e., the blade system will slide. Due to the presence of backlash, the blade will impact the drive gear back and forth with the gear ring, which will aggravate the fatigue damage of the system.

[0004] 2. The gear surface of the pitch gear ring is severely worn in the long-term working position (near 0°). In the long-term working position, due to the slippage of the blade system, the vibration impact and fretting wear caused by the slippage of the blade system make it difficult to form a lubricating oil film on the gear surface, resulting in severe wear.

[0005] 3. Due to the slippage of the blade system, the pitch system will experience vibration and impact, which will exacerbate the fretting wear between the bearing rollers and raceways. This will eventually lead to premature spalling of the bearing raceways, affecting the reliability of the unit.

[0006] 4. As the turbine units and blades continue to grow larger, the torque requirements for the pitch motor brakes are also increasing, leading to difficulties in selection and increased costs. Summary of the Invention

[0007] The present invention aims to provide, for example, a wind turbine pitch transmission system that can improve the problem of wear between the pitch bearing and the pitch reducer, which affects the pitch life and reliability of the turbine.

[0008] The present invention also aims to provide a wind turbine generator set that can improve the problem of wear between the pitch bearing and the pitch reducer, which affects the pitch life and reliability of the generator set.

[0009] The embodiments of the present invention can be implemented as follows:

[0010] An embodiment of the present invention provides a wind turbine pitch transmission system, including a hub, a pitch motor, a pitch reducer, a pitch bearing, a blade flange, blades, and a braking assembly; the pitch bearing is fixed on the hub, the blade flange is fixed to the pitch bearing, the blades are fixed to the blade flange, the pitch motor, the pitch reducer, and the pitch bearing are sequentially connected in a transmission manner, and the pitch motor is used to drive the blades to rotate;

[0011] The braking assembly includes a mechanical brake and / or a hydraulic brake. The mechanical brake is used to be fixed between the hub and the blade flange, and the mechanical brake is used to make damping contact with the blade flange. The hydraulic brake is used to be fixed between the hub and the blade flange, and the hydraulic brake is used to make damping contact with the blade flange.

[0012] In addition, the wind turbine pitch transmission system provided in the embodiments of the present invention may also have the following additional technical features:

[0013] Optionally, the mechanical brake includes a brake cylinder and a mechanical friction pad, the brake cylinder is fixed to the wheel hub, the mechanical friction pad is fixed to the brake cylinder, and the mechanical friction pad is in damping contact with the blade flange.

[0014] Optionally, the brake cylinder body and the mechanical friction plate are coaxially fixed; the hub has a web plate arranged parallel to the blade flange, and the brake cylinder body is fixed on the web plate.

[0015] Optionally, the mechanical brakes are multiple, and the multiple mechanical brakes are fixed at intervals between the hub and the blade flange around the rotation center line of the pitch bearing.

[0016] Optionally, the hydraulic brake includes a brake mounting pad, a hydraulic brake caliper, and a hydraulic friction pad. The brake mounting pad is detachably fixed to the wheel hub, and the hydraulic brake caliper is detachably mounted on the brake mounting pad. The hydraulic friction pad is fixed to the inner side of the hydraulic brake caliper. The hydraulic brake caliper is used to clamp or release the blade flange, and the hydraulic friction pad is used to make damping contact with the blade flange.

[0017] Optionally, there are multiple hydraulic brakes, which are fixed at intervals between the hub and the blade flange along the rotation center line of the pitch bearing.

[0018] Optionally, the blade flange has an inner ring and an outer ring, the outer ring of the blade flange is fixed to the pitch bearing, and the hydraulic brake is fixed to the inner ring of the flange.

[0019] Optionally, in the state of generating electricity and without pitch control, the damping torque provided by the braking assembly is a first braking torque; in the state of pitch control, the damping torque provided by the braking assembly is a second braking torque; and in the state of shutdown, the damping torque provided by the braking assembly is a third braking torque, wherein the third braking torque > the first braking torque > the second braking torque.

[0020] Optionally, the wind turbine pitch transmission system further includes an electromagnetic brake, which is fixed on the mechanical shaft of the pitch motor.

[0021] An embodiment of the present invention also provides a wind turbine generator set. The wind turbine generator set includes a wind turbine pitch transmission system.

[0022] The beneficial effects of the wind turbine pitch transmission system and wind turbine generator set of the present invention include, for example:

[0023] The wind turbine pitch transmission system includes a hub, a pitch motor, a pitch reducer, a pitch bearing, a blade flange, blades, and a braking assembly. The pitch bearing is fixed to the hub, the blade flange is fixed to the pitch bearing, and the blades are fixed to the blade flange. The pitch motor, pitch reducer, and pitch bearing are sequentially connected for transmission. The pitch motor drives the blades to rotate. The braking assembly includes a mechanical brake and / or a hydraulic brake. The mechanical brake is fixed between the hub and the blade flange and makes damped contact with the blade flange. The hydraulic brake is fixed between the hub and the blade flange and makes damped contact with the blade flange.

[0024] The braking assembly enables braking at the output end, solving the problem of delay in the transmission of motor power from the input end to the blades and the inability to suppress the torque generated by the blades' own weight and wind load. It fundamentally solves the vibration caused by the slippage of the pitch bearing gear ring due to the blades, reduces additional fatigue damage to the transmission system, and improves the reliability of the transmission system.

[0025] Wind turbine generator sets, including the aforementioned wind turbine pitch transmission system, address the issue of wear between the pitch bearing and the pitch reducer, which affects the pitch life and reliability of the generator set. Attached Figure Description

[0026] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as a limitation on the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0027] Figure 1 This is a partial sectional view along the rotation centerline of the wind turbine pitch transmission system provided in this embodiment;

[0028] Figure 2 This is a partial schematic diagram of the wind turbine pitch transmission system provided in this embodiment.

[0029] Icons: 10 - Wind turbine pitch transmission system; 110 - Pitch motor; 111 - Electromagnetic brake; 120 - Pitch reducer; 121 - Output gear; 200 - Hub; 300 - Pitch bearing; 310 - Stationary ring; 320 - Moving ring; 330 - Gear ring; 340 - Pitch bearing roller; 400 - Blade; 500 - Blade flange; 600 - Mechanical brake; 610 - Brake cylinder; 620 - Mechanical friction pad; 700 - Hydraulic brake; 710 - Hydraulic brake caliper; 720 - Hydraulic friction pad; 730 - Brake mounting pad. Detailed Implementation

[0030] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The components of the embodiments of the present invention described and shown in the accompanying drawings can generally be arranged and designed in various different configurations.

[0031] Therefore, the following detailed description of the embodiments of the invention provided in the accompanying drawings is not intended to limit the scope of the claimed invention, but merely to illustrate selected embodiments of the invention. All other embodiments obtained by those skilled in the art based on the embodiments of the invention without inventive effort are within the scope of protection of the invention.

[0032] It should be noted that similar labels and letters in the following figures indicate similar items. Therefore, once an item is defined in one figure, it does not need to be further defined and explained in subsequent figures.

[0033] In the description of this invention, it should be noted that if terms such as "upper," "lower," "inner," or "outer" are used to indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship in which the product of this invention is usually placed, they are only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this invention.

[0034] Furthermore, the terms "first" and "second" are used only to distinguish descriptions and should not be interpreted as indicating or implying relative importance.

[0035] It should be noted that, where there is no conflict, the features in the embodiments of the present invention can be combined with each other.

[0036] The following is combined with Figures 1 to 2 The wind turbine pitch transmission system 10 provided in this embodiment will be described in detail.

[0037] Please refer to Figure 1 and Figure 2 An embodiment of the present invention provides a wind turbine pitch transmission system 10, including a hub 200, a pitch motor 110, a pitch reducer 120, a pitch bearing 300, a blade flange 500, a blade 400, and a braking assembly. The pitch bearing 300 is fixed to the hub 200, the blade flange 500 is fixed to the pitch bearing 300, and the blade 400 is fixed to the blade flange 500. The pitch motor 110, the pitch reducer 120, and the pitch bearing 300 are sequentially connected for transmission. The pitch motor 110 is used to drive the blade 400 to rotate. The braking assembly includes a mechanical brake 600 and / or a hydraulic brake 700. The mechanical brake 600 is fixed between the hub 200 and the blade flange 500 and is used for damped contact with the blade flange 500. The hydraulic brake 700 is fixed between the hub 200 and the blade flange 500 and is used for damped contact with the blade flange 500.

[0038] The pitch motor 110 and the pitch reducer 120 form a pitch drive system; the pitch bearing 300 includes a pitch stationary ring 310, a pitch moving ring 320, a gear ring 330, and a pitch bearing roller 340. The output teeth 121 of the pitch reducer 120 mesh with the gear ring 330 of the pitch bearing 300 to form an execution system for performing pitch control; the blade 400 and the gear ring 330 of the pitch bearing 300 are fixedly connected together through the blade flange 500. The pitch motor 110 sequentially drives the pitch reducer 120, the pitch bearing 300, the blade flange 500, and the blade 400 to rotate, thereby changing the angle of the blade 400; a braking assembly is installed on the blade flange 500, which is fixed on the hub 200 and contacts the blade flange 500 to achieve braking.

[0039] "Mechanical brake 600 and / or hydraulic brake 700" means that the braking assembly can use mechanical brake 600 alone, hydraulic brake 700 alone, or a combination of mechanical brake 600 and hydraulic brake 700. The hydraulic brake 700 can control the magnitude of the braking torque, providing high flexibility. When used in combination, the total braking damping is a constant damping provided by the mechanical brake plus damping in different states provided by the hydraulic brake. The choice of which brake to use depends on the requirements.

[0040] The braking assembly enables braking at the output end, solving the problem of delayed power transmission from the input motor to the blade 400 and the inability to suppress the torque generated by the blade 400 under its own weight and wind load. It fundamentally solves the vibration caused by the slippage of the pitch bearing 300 gear ring 330 due to the blade 400, reduces additional fatigue damage to the transmission system, and improves the reliability of the transmission system.

[0041] Figure 1 and Figure 2 The middle section shows a combination arrangement of hydraulic brake 700 and mechanical brake 600. By controlling the pressure of hydraulic brake 700, the braking assembly can provide a variety of braking forces, which can be used in different stages of the pitch system.

[0042] Reference Figure 2 In this embodiment, in the state of generating electricity and not changing the pitch, the damping torque provided by the braking component is the first braking torque; in the state of changing the pitch, the damping torque provided by the braking component is the second braking torque; and in the state of stopping, the damping torque provided by the braking component is the third braking torque, wherein the third braking torque > the first braking torque > the second braking torque.

[0043] During the power generation process without changing the pitch, the blade 400 remains stationary at a certain angle. The hydraulic brake 700 provides residual pressure of abar, and the braking system provides the first braking torque A, maintaining the stationary state of the blade 400 in the circumferential direction of the blade root. This reduces the oscillation effect of the blade 400 during the power generation process, thereby reducing the fretting wear of the bearing raceway and reducing the impact and wear of the gear ring 330.

[0044] During pitch control, the hydraulic brake 700 provides b Bar pressure, the braking system provides a second braking torque B, and the pitch control system provides a certain amount of damping to reduce or eliminate the delay effect during the power output process of the pitch motor 110 and reduce or eliminate the slippage of the blade 400 system.

[0045] When the machine is stopped, the hydraulic brake 700 provides high pressure c Bar, the braking system provides the third braking torque C, and the auxiliary motor electromagnetic brake locks the blade 400, improving locking reliability, reducing the force on the transmission system, and improving the reliability of the transmission system.

[0046] c Bar > a bar > b Bar, fundamentally solving the vibration caused by the slippage of the pitch bearing 300 gear ring 330 due to the blade 400, reducing additional fatigue damage to the transmission system, and improving the reliability of the transmission system.

[0047] Reference Figure 2 In this embodiment, the wind turbine pitch transmission system 10 also includes an electromagnetic brake 111, which is fixed on the mechanical shaft of the pitch motor 110. This achieves a braking method that combines input-end braking and output-end braking. With output-end braking plus braking at the pitch motor 110 end, the system's braking capacity will consist of two parts, effectively reducing the selection pressure and cost of the electromagnetic brake 111 for the pitch motor 110.

[0048] Reference Figure 2 In this embodiment, the mechanical brake 600 includes a brake cylinder 610 and a mechanical friction plate 620. The brake cylinder 610 is fixed on the wheel hub 200, the mechanical friction plate 620 is fixed to the brake cylinder 610, and the mechanical friction plate 620 is in damped contact with the blade flange 500.

[0049] Regardless of the wind turbine's state, the mechanical friction plate 620 of the mechanical brake 600 is in frictional contact with the blade flange 500, ensuring that fatigue damage to the transmission system can be reduced to varying degrees during power generation, pitch control, and shutdown.

[0050] Reference Figure 2 In this embodiment, the brake cylinder 610 and the mechanical friction plate 620 are coaxially fixed; the hub 200 has a web plate arranged parallel to the blade flange 500, and the brake cylinder 610 is fixed on the web plate.

[0051] The brake cylinder body 610 and the mechanical friction plate 620 are fixed between the web of the hub 200 and the vane flange 500; the mechanical friction plate 620 is fixed directly opposite the brake cylinder body 610, and the force of the brake cylinder body 610 and the mechanical friction plate 620 acts positively on the vane flange 500.

[0052] Reference Figure 2 In this embodiment, there are multiple mechanical brakes 600, which are fixed at intervals between the hub 200 and the blade flange 500 around the rotation center line of the pitch bearing 300.

[0053] The number of mechanical brakes 600 is n sets, where n≥1. When there are multiple mechanical brakes 600, they are arranged along the circumferential direction. The number of n is set by the load distribution of the wind turbine's pitch system and is set as needed.

[0054] Reference Figure 2 In this embodiment, the hydraulic brake 700 includes a brake mounting pad 730, a hydraulic brake caliper 710, and a hydraulic friction pad 720. The brake mounting pad 730 is detachably fixed to the wheel hub 200. The hydraulic brake caliper 710 is detachably mounted on the brake mounting pad 730. The hydraulic friction pad 720 is fixed on the inner side of the hydraulic brake caliper 710. The hydraulic brake caliper 710 is used to clamp or release the blade flange 500, and the hydraulic friction pad 720 is used to make damping contact with the blade flange 500.

[0055] The hydraulic brake 700 is a hydraulic caliper brake, which includes a hydraulic brake caliper 710 and hydraulic friction pads 720. The two hydraulic friction pads 720 are located on both sides of the vane flange 500 to brake the rotation of the vane flange 500. The braking pressure of the hydraulic brake 700 is adjustable and can be adjusted according to actual conditions, making it suitable for a wider range of applications.

[0056] Brake mounting shim 730 is used to ensure accurate installation positioning. During the installation of hydraulic caliper brakes, brake mounting shim 730 is used to adjust the clearance between the hub web and the blade flange to ensure dimensional accuracy. Different hydraulic caliper brakes can be matched by changing the size of the brake mounting shim 730.

[0057] Reference Figure 2 In this embodiment, there are multiple hydraulic brakes 700, which are fixed at intervals between the hub 200 and the blade flange 500 along the rotation center line of the pitch bearing 300.

[0058] The number of hydraulic brakes 700 is n sets, where n≥1. When there are multiple hydraulic brakes 700, they are arranged along the circumferential direction. The number of hydraulic brakes 700 is set by the load distribution of the wind turbine pitch system and is set as needed.

[0059] Reference Figure 2 In this embodiment, the blade flange 500 has an inner ring and an outer ring. The outer ring of the blade flange 500 is fixed to the pitch bearing 300, and the hydraulic brake 700 is fixed to the inner ring of the flange. The hydraulic brake caliper 710 of the brake caliper clamps and brakes the blade flange 500 from the inner ring of the blade flange 500.

[0060] Reference Figure 2In this embodiment, the mechanical brake 600 is fixed between the inner ring of the pitch bearing 300 and the hydraulic brake 700. Multiple mechanical brakes 600 are arranged around multiple hydraulic brakes 700.

[0061] According to the wind turbine pitch transmission system 10 provided in this embodiment, the working principle of the wind turbine pitch transmission system 10 is as follows: by using a braking component, the system solves the problem of the delay in transmitting the motor output to the blade 400 at the input end, and the inability to suppress the torque generated by the blade 400 under its own weight and wind load, thereby reducing fatigue wear and ensuring the smooth operation of the pitch transmission system.

[0062] The wind turbine pitch transmission system 10 provided in this embodiment has at least the following advantages:

[0063] Based on the traditional pitch transmission system, a braking component is added. This component can be a hydraulic brake 700, a mechanical brake 600, or a combination thereof. It systematically solves the problem of delay in transmitting motor output to blades 400, and the inability to suppress the torque generated by blades 400 under their own weight and wind load. It fundamentally solves the vibration caused by slippage of the pitch bearing 300 gear ring 330 due to blades 400, reducing additional fatigue damage to the transmission system and improving its reliability. It effectively mitigates or resolves wear problems on the blade surface near the zero position during long-term operation; it effectively mitigates or resolves fretting wear problems on the bearing raceway, improving bearing raceway life; it effectively mitigates or resolves impact noise problems between the gear ring 330 and the output teeth 121 of the pitch reducer 120 caused by blades 400 overspeeding during pitch control; and it improves the braking reliability of the unit in the shutdown state, reduces the load on the transmission system, and enhances its overall reliability.

[0064] By setting up a braking system at the output end, the braking capacity of the system will consist of two parts: output end braking and braking at the pitch motor 110 end. This will effectively reduce the selection pressure and cost of the electromagnetic brake 111 of the pitch motor 110.

[0065] Embodiments of the present invention also provide a wind turbine generator set. The wind turbine generator set includes a wind turbine pitch transmission system 10. The wind turbine generator set also includes a tower, with a hub 200 rotatably mounted on the tower. This improves the problem of wear easily occurring between the pitch bearing 300 and the pitch reducer 120, which affects the pitch life and reliability of the generator set.

[0066] The above are merely specific embodiments of the present invention, but the scope of protection of the present invention is not limited thereto. Any variations or substitutions that can be easily conceived by those skilled in the art within the technical scope disclosed in the present invention should be included within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A wind turbine pitch transmission system, characterized in that, The system includes a hub (200), a pitch motor (110), a pitch reducer (120), a pitch bearing (300), a blade flange (500), blades (400), and a braking assembly. The pitch bearing (300) is fixed to the hub (200), the blade flange (500) is fixed to the pitch bearing (300), and the blades (400) are fixed to the blade flange (500). The pitch motor (110), the pitch reducer (120), and the pitch bearing (300) are sequentially connected in a transmission manner. The pitch motor (110) is used to drive the blades (400) to rotate. The braking assembly includes a mechanical brake (600) and a hydraulic brake (700). The mechanical brake (600) is fixed between the hub (200) and the blade flange (500) and is used for damped contact with the blade flange (500). The hydraulic brake (700) is fixed between the hub (200) and the blade flange (500) and is used for damped contact with the blade flange (500). The mechanical brake (600) provides constant damping, and the hydraulic brake (700) provides damping in different states; in the generator state and without pitch control, the damping torque provided by the braking assembly is a first braking torque; in the pitch control state, the damping torque provided by the braking assembly is a second braking torque; in the shutdown state, the damping torque provided by the braking assembly is a third braking torque; wherein, the third braking torque > the first braking torque > the second braking torque; The mechanical brake (600) includes a brake cylinder (610) and a mechanical friction plate (620). The brake cylinder (610) is fixed on the wheel hub (200), the mechanical friction plate (620) is fixed to the brake cylinder (610), and the mechanical friction plate (620) is in damped contact with the blade flange (500).

2. The wind turbine pitch transmission system according to claim 1, characterized in that, The brake cylinder body (610) and the mechanical friction plate (620) are coaxially fixed; the hub (200) has a web plate arranged parallel to the blade flange (500), and the brake cylinder body (610) is fixed on the web plate.

3. The wind turbine pitch transmission system according to claim 1 or 2, characterized in that, The mechanical brakes (600) are multiple in number, and the multiple mechanical brakes (600) are fixed at intervals between the hub (200) and the blade flange (500) around the rotation center line of the pitch bearing (300).

4. The wind turbine pitch transmission system according to claim 1 or 2, characterized in that, The hydraulic brake (700) includes a brake mounting pad (730), a hydraulic brake caliper (710), and a hydraulic friction pad (720). The brake mounting pad (730) is detachably fixed to the wheel hub (200). The hydraulic brake caliper (710) is detachably mounted on the brake mounting pad (730). The hydraulic friction pad (720) is fixed on the inner side of the hydraulic brake caliper (710). The hydraulic brake caliper (710) is used to clamp or release the blade flange (500). The hydraulic friction pad (720) is used to make damping contact with the blade flange (500).

5. The wind turbine pitch transmission system according to claim 4, characterized in that, The number of hydraulic brakes (700) is multiple, and the multiple hydraulic brakes (700) are fixed at intervals between the hub (200) and the blade flange (500) along the rotation center line of the pitch bearing (300).

6. The wind turbine pitch transmission system according to claim 4, characterized in that, The blade flange (500) has an inner ring and an outer ring, the outer ring of the blade flange (500) is fixed to the pitch bearing (300), and the hydraulic brake (700) is fixed to the inner ring of the flange.

7. The wind turbine pitch transmission system according to claim 1 or 2, characterized in that, The wind turbine pitch transmission system also includes an electromagnetic brake (111), which is fixed on the mechanical shaft of the pitch motor (110).

8. A wind turbine generator set, characterized in that, The wind turbine generator set includes the wind turbine pitch transmission system as described in any one of claims 1-7.

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