Wind turbine blade clearance control system and method

Abstract

The invention discloses a wind turbine blade clearance control system and method. The system comprises a winding coil, a moving base, an annular track, a ferromagnetic blade tip and a power supply. The winding coil is arranged on the moving base, the moving base is slidably arranged on the annular track, the annular track is arranged on the tower in the horizontal direction, a driving mechanism is arranged on the moving base, the power supply supplies power to the driving mechanism of the moving base, and the winding coil is connected to a high-frequency AC power supply through a cable. According to the principle of mutual repulsion of like magnetic poles, the invention utilizes the Lorentz force between the high-frequency magnetic field generated by the winding coil and the ferromagnetic blade tip to control the blade clearance distance to always be within a safe range, and can realize the synchronous yaw of the winding coil and the cabin and the same direction facing the wind, and the blade clearance is controlled by a contactless method, and the system has strong anti-interference ability and high reliability.

Description

Technical Field

[0001] The invention belongs to the technical field of wind power generation, and in particular relates to a wind turbine blade clearance control system and method. Background Art

[0002] The blade clearance of a wind turbine refers to the minimum geometric distance from the blade tip to the tower surface during the operation of the unit. As the length of the wind turbine blade increases, the blade stiffness decreases, and the blade deformation is large at higher wind speeds. Under extreme wind conditions such as extreme wind speeds, wind direction changes, and extreme wind shear, accidents such as blade tip sweeping the tower may occur, seriously affecting the safety of wind turbine operation. At present, conventional blade clearance monitoring methods include image recognition, laser ranging, millimeter wave radar, etc. When the blade clearance value is detected to be small, the blade clearance is generally increased by changing the pitch and reducing the power to ensure the safety of the unit; when the blade clearance value is extremely small, the only way to ensure the safety of the unit is to use emergency shutdown. Summary of the invention

[0003] In order to solve the problems existing in the prior art, the present invention provides a wind turbine blade clearance control system and method, which uses the principle of mutual repulsion of like magnetic poles to change the blade clearance, thereby reducing the power generation loss caused by power reduction or shutdown while ensuring the safe operation of the unit.

[0004] In order to achieve the above-mentioned purpose, the technical solution adopted by the present invention is: a wind turbine blade clearance control system, including a winding coil, a moving base, a circular track, a ferromagnetic blade tip and a power supply, the winding coil is arranged on the moving base, the moving base is slidably arranged on the circular track, the circular track is arranged on the tower in the horizontal direction, a driving mechanism is arranged on the moving base, the power supply supplies power to the driving mechanism of the moving base, and the winding coil is connected to a high-frequency AC power supply through a cable.

[0005] The control signal input end of the driving mechanism is connected to the output end of the main control system of the wind turbine generator set.

[0006] The circular track is in the form of a railway track, and the track close to the tower side is fixed to the tower by welding.

[0007] The moving base is provided with a C-type clamp on the outer side away from the tower.

[0008] A buffer spring or a buffer pad is arranged between the C-shaped clamp and the annular track

[0009] The control signal input terminal of the high-frequency AC power supply is connected to the output terminal of the main control system of the wind turbine generator set.

[0010] The circular track adopts a monorail with an H-shaped steel or I-shaped steel cross section. The driving mechanism includes a driving motor and a roller. The roller is arranged on the upper surface of the circular track. Limiting columns are arranged on both sides of the driving mechanism and the circular track, and bearings are arranged on the limiting columns.

[0011] The power source includes a power source provided by a wind generator and a storage battery, wherein the power input end of the storage battery is connected to the power output end of the wind generator and the output end of the solar panel.

[0012] Based on the wind turbine blade clearance control method of the system of the present invention, a high-frequency alternating current is passed through the winding coil to generate a high-frequency electromagnetic field, and at the same time, the winding coil yaws along the circular track with the cabin;

[0013] During the operation of a wind turbine, when the ferromagnetic tip of the blade passes over the tower, the high-frequency electromagnetic field of the winding coil generates high-frequency eddy currents on the surface of the ferromagnetic tip, causing the blade to be affected by the Lorentz force in the direction away from the tower, thereby achieving control of the clearance of the wind turbine blade.

[0014] The power of the high-frequency alternating current loaded on the winding coil is adjusted. When monitoring finds that the blade clearance value is small, or the wind turbine has no clearance monitoring device but the monitored wind speed is large, the power of the high-frequency alternating current of the winding coil is increased to ensure that the blade clearance distance is always within a safe range.

[0015] Compared with the prior art, the present invention has at least the following beneficial effects: based on the principle of mutual repulsion between like magnetic poles, the present invention utilizes the Lorentz force between the high-frequency magnetic field generated by the winding coil and the ferromagnetic blade tip to control the blade clearance distance to always be within a safe range; the winding coil can achieve synchronous yaw with the cabin and face the wind in the same direction; a contactless method is used to control the blade clearance, and the system has strong anti-interference ability and high reliability.

[0016] Furthermore, the motion base can receive the main control information of the wind turbine set, obtain the real-time yaw angle of the nacelle, and ensure that the winding coil and the nacelle yaw synchronously and face the wind in the same direction.

[0017] Furthermore, the control signal input terminal of the high-frequency AC power supply is connected to the output terminal of the wind turbine main control system, and the power of the high-frequency AC power supply is specifically adjusted according to the wind speed and the blade clearance value. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic diagram of the overall structure of the present invention.

[0019] Figure 2 It is a schematic structural diagram of the annular track of the present invention.

[0020] Figure 3 It is a schematic structural diagram of the motion base of the present invention.

[0021] The meanings of the various figures are as follows: 1. winding coil; 2. moving base; 3. annular track; 4. ferromagnetic blade tip; 5. C-type clamp. DETAILED DESCRIPTION

[0022] The present invention will be described in more detail below in conjunction with the accompanying drawings and specific embodiments.

[0023] like Figure 1 As shown, the present invention provides a wind turbine blade clearance control system, including a winding coil 1, a moving base 2, a circular track 3, a ferromagnetic blade tip 4 and a power supply, the winding coil 1 is arranged on the moving base 2, the moving base 2 is slidably arranged on the circular track 3, the circular track 3 is arranged on the tower in the horizontal direction, a driving mechanism is arranged on the moving base 2, the power supply supplies power to the driving mechanism of the moving base 2, and the winding coil 1 is connected to a high-frequency AC power supply through a cable.

[0024] The control signal input end of the driving mechanism is connected to the output end of the main control system of the wind turbine generator set.

[0025] The annular track 3 is in the form of a railway track, and the track close to the tower side is fixed to the tower by welding.

[0026] The motion base 2 is provided with a C-shaped clamp on the outer side away from the tower; the motion base is additionally provided with a C-shaped clamp on the outer side away from the tower to prevent the motion base from tipping over under extreme wind speeds.

[0027] Optionally, a buffer spring or a buffer pad is provided between the C-shaped clamp and the annular track to buffer external forces in extreme weather and prevent the winding coil 1 and the moving base 2 from being subjected to excessive instantaneous stress.

[0028] The control signal input terminal of the high-frequency AC power supply is connected to the output terminal of the main control system of the wind turbine generator set.

[0029] As an optional embodiment, the annular track 3 adopts a monorail with an H-shaped steel or I-shaped steel cross-section, and the driving mechanism includes a driving motor and rollers, the rollers are arranged on the upper surface of the annular track 3, and limit columns are arranged on both sides of the driving mechanism and the annular track 3, and bearings are arranged on the limit columns.

[0030] The power source includes a power source provided by a wind generator and a storage battery, wherein the power input end of the storage battery is connected to the power output end of the wind generator and the output end of the solar panel.

[0031] Based on the wind turbine blade clearance control method of the system of the present invention, a high-frequency alternating current is passed through the winding coil 1 to generate a high-frequency electromagnetic field, and at the same time, the winding coil 1 yaws along the circular track 3 with the cabin;

[0032] During the operation of the wind turbine, when the ferromagnetic blade tip passes over the tower, the high-frequency electromagnetic field of the winding coil 1 generates high-frequency eddy currents on the surface of the ferromagnetic blade tip, causing the blade to be affected by the Lorentz force in the direction away from the tower, thereby achieving control of the wind turbine blade clearance.

[0033] The motion base is equipped with a motion control system, which can receive the main control information of the wind turbine set, obtain the real-time yaw angle of the nacelle, and ensure that the winding coil and the nacelle yaw synchronously and face the wind in the same direction.

[0034] The winding coil is passed through a cable with high-frequency alternating current, and the power of the high-frequency alternating current is specifically adjusted according to the wind speed and the blade clearance value; the cable is hung below the outer side of the circular track.

[0035] Furthermore, the wind turbine blade clearance control method of the present invention has the following process:

[0036] A high-frequency alternating current is passed through the winding coil to generate a high-frequency electromagnetic field, and the winding coil yaws synchronously with the cabin;

[0037] During the operation of a wind turbine, when the ferromagnetic blade tip passes over the tower, the high-frequency electromagnetic field of the winding coil generates a high-frequency eddy current on the surface of the ferromagnetic blade tip, causing the blade to be affected by the Lorentz force in the direction away from the tower.

[0038] The power of the high-frequency alternating current of the winding coil is adjustable. When the conventional blade clearance monitoring device detects that the blade clearance value is small, or the wind turbine has no clearance monitoring device but the wind speed measured by its main control system is large, the power of the high-frequency alternating current of the winding coil is increased to ensure that the blade clearance distance is always within a safe range.

[0039] Although the embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and cannot be understood as limiting the present invention. Those skilled in the art may change, modify, replace and modify the above embodiments within the scope of the present invention without departing from the principles and purpose of the present invention. The scope of the present invention is defined by the appended claims and their equivalents.

Claims

1. A wind turbine blade clearance control system, characterized in that: The invention comprises a winding coil (1), a moving base (2), a circular track (3), a ferromagnetic blade tip (4) and a power source, wherein the winding coil (1) is arranged on the moving base (2), the moving base (2) is slidably arranged on the circular track (3), the circular track (3) is arranged on the tower in the horizontal direction, a driving mechanism is arranged on the moving base (2), the power source supplies power to the driving mechanism of the moving base (2), and the winding coil (1) is connected to a high-frequency AC power source through a cable; the circular track (3) adopts a monorail with an H-shaped steel or I-shaped steel cross section, the driving mechanism comprises a driving motor and a roller, the roller is arranged on the upper surface of the circular track (3), limiting columns are arranged on both sides of the driving mechanism and the circular track (3), and bearings are arranged on the limiting columns; the power source comprises a power source provided by a wind turbine and a storage battery, and the power input end of the storage battery is connected to the power output end of the wind turbine and the output end of the solar panel.

2. The wind turbine blade clearance control system according to claim 1, characterized in that: The control signal input end of the driving mechanism is connected to the output end of the main control system of the wind turbine generator set.

3. The wind turbine blade clearance control system according to claim 1, characterized in that: The annular track (3) is in the form of a railway track, and the track close to the tower side is fixed to the tower by welding.

4. The wind turbine blade clearance control system according to claim 1, characterized in that: A C-shaped clamp is arranged on the outer side of the moving base (2) away from the tower.

5. The wind turbine blade clearance control system according to claim 4, characterized in that: A buffer spring or a buffer pad is arranged between the C-shaped clamp and the annular track.

6. The wind turbine blade clearance control system according to claim 1, characterized in that: The control signal input terminal of the high-frequency AC power supply is connected to the output terminal of the main control system of the wind turbine generator set.

7. A wind turbine blade clearance control method based on the system according to any one of claims 1 to 6, characterized in that: A high-frequency alternating current is passed through the winding coil (1) to generate a high-frequency electromagnetic field, and at the same time, the winding coil (1) yaws along the circular track (3) along with the cabin; During the operation of the wind turbine, when the ferromagnetic blade tip of the blade passes over the tower, the high-frequency electromagnetic field of the winding coil (1) generates high-frequency eddy currents on the surface of the ferromagnetic blade tip, causing the blade to be acted upon by a Lorentz force in a direction away from the tower, thereby achieving control of the clearance of the wind turbine blade.

8. The wind turbine blade clearance control method according to claim 7, characterized in that: The power of the high-frequency alternating current loaded on the winding coil (1) is adjusted. When the blade clearance value is detected to be small through monitoring, or when the wind turbine has no clearance monitoring device but the wind speed detected through monitoring is large, the power of the high-frequency alternating current loaded on the winding coil is increased, thereby ensuring that the blade clearance distance is always within a safe range.

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