A wind turbine intelligent load reduction blade and working method thereof

Abstract

The present invention discloses an intelligent load reduction blade for a wind turbine, comprising a blade skeleton composed of a leading edge of a blade, a leading edge panel, a main beam, a trailing edge deformation zone and a trailing edge connected in sequence, a plurality of groups of main beam piezoelectric fiber actuators are respectively laid in the first main beam and the second main beam along the span direction of the blade, a spring clip is arranged on the trailing edge side of the main beam, a clamping portion of the spring clip is inserted between the first trailing edge deformation zone and the second trailing edge deformation zone, and a plurality of groups of trailing edge piezoelectric fiber actuators are clamped on the clamping portion of the spring clip along the span direction of the blade. By arranging piezoelectric fiber actuators at key positions of the main beam and the trailing edge, the present invention adds three active and passive load reduction modes, namely, main beam bending-torsion coupling load reduction, main beam deformation load reduction driven by the main beam piezoelectric fiber actuator, and trailing edge deformation load reduction driven by the trailing edge piezoelectric fiber actuator, to the blade on the basis of the traditional independent variable pitch load reduction mode. The present invention can make up for the shortcomings of the independent variable pitch load reduction mode and greatly improve the flexibility and reliability of load reduction of large wind turbines.

Description

Technical Field

[0001] The invention belongs to the field of wind turbine blade design, and in particular relates to a wind turbine intelligent load reduction blade and a working method thereof. Background Art

[0002] Horizontal axis wind turbines mainly use independent variable pitch control to change the blade pitch angle to achieve load reduction control during variable working conditions. With the trend of blade enlargement, the blade inertia increases, the moment of inertia in the direction of the pitch angle increases, and the response of the variable pitch device becomes slower; on the other hand, the inflow conditions from the root to the tip of the blade change significantly, and the overall variable pitch method can no longer effectively reduce the load fluctuations caused by periodic flow changes, and cannot cope with the local effects caused by random and turbulent flows. Summary of the invention

[0003] The purpose of the present invention is to provide a wind turbine intelligent load reduction blade and a working method thereof, so as to improve the flexibility and reliability of load reduction of large wind turbines.

[0004] To solve the above problems, the technical solution of the present invention is:

[0005] A wind turbine intelligent load reduction blade comprises a blade skeleton formed by sequentially connecting a leading edge of a blade, a leading edge panel, a main beam, a trailing edge deformation zone and a trailing edge, the leading edge panel comprising a first leading edge panel and a second leading edge panel arranged in pairs up and down, one end of the leading edge of the blade is connected to the first leading edge panel, and the other end of the leading edge of the blade is connected to the second leading edge panel, the main beam comprises a first main beam and a second main beam arranged in pairs up and down, the first main beam is connected to the first leading edge panel, the second main beam is connected to the second leading edge panel, the trailing edge deformation zone comprises a first trailing edge deformation zone and a second trailing edge deformation zone arranged in pairs up and down, the first trailing edge deformation zone is connected to the first main beam, the second trailing edge deformation zone is connected to the second main beam, and a free end of the first trailing edge deformation zone and a free end of the second trailing edge deformation zone are connected by the trailing edge;

[0006] A plurality of groups of main beam piezoelectric fiber actuators are respectively arranged in the first main beam and the second main beam along the blade span direction, a spring clip is arranged on the trailing edge side of the main beam, two free ends of the spring clip are respectively connected to the first main beam and the second main beam, a clamping portion of the spring clip is inserted between the first trailing edge deformation zone and the second trailing edge deformation zone, and a plurality of groups of trailing edge piezoelectric fiber actuators are clamped on the clamping portion of the spring clip along the blade span direction;

[0007] A slip ring is installed at the root of the blade, and the slip ring is electrically connected to several groups of the main beam piezoelectric fiber actuators respectively, and the slip ring is electrically connected to several groups of the trailing edge piezoelectric fiber actuators respectively.

[0008] Preferably, at least one web is installed between the first main beam and the second main beam.

[0009] Preferably, the first main beam and the second main beam are made of fiber composite material plies, and the fiber composite material plies of the first main beam and the second main beam are laid in the same direction.

[0010] Preferably, the first trailing edge deformation zone and the second trailing edge deformation zone are filled with flexible material.

[0011] Preferably, the flexible material is silica gel or pearl cotton or a combination of the two.

[0012] Based on the same inventive concept, the present invention also provides a working method for wind turbine intelligent load reduction blades. When the wind speed of the wind turbine inflow exceeds the rated wind speed, the blades are subjected to increased force and bend and deform. The first main beam and the second main beam undergo bending-torsion coupling deformation, and the blades are twisted and deformed while bending, thereby reducing the blade attack angle and the rotor speed.

[0013] If the wind wheel speed cannot drop to the rated speed value, the main beam piezoelectric fiber actuator is controlled to drive the first main beam and the second main beam to increase deformation and reduce the angle of attack, and the trailing edge piezoelectric fiber actuator is controlled to drive the trailing edge to deform toward the suction surface, thereby reducing the lift of the blade and further controlling the wind wheel speed.

[0014] Due to the adoption of the above technical solution, the present invention has the following advantages and positive effects compared with the prior art:

[0015] 1) The present invention provides an intelligent load reduction blade for a wind turbine, comprising a blade skeleton composed of a leading edge of a blade, a leading edge panel, a main beam, a trailing edge deformation zone and a trailing edge connected in sequence, a plurality of groups of main beam piezoelectric fiber actuators are respectively laid in the first main beam and the second main beam along the span direction of the blade, a spring clip is arranged on the trailing edge side of the main beam, two free ends of the spring clip are respectively connected to the first main beam and the second main beam, a clamping portion of the spring clip is inserted between the first trailing edge deformation zone and the second trailing edge deformation zone, and a plurality of groups of trailing edge piezoelectric fiber actuators are clamped on the clamping portion of the spring clip along the span direction of the blade, and the present invention arranges piezoelectric fiber actuators at key positions of the main beam and the trailing edge, so that the blade adds three active and passive load reduction modes, namely, main beam bending-torsion coupling load reduction, main beam deformation load reduction driven by the main beam piezoelectric fiber actuator, and trailing edge deformation load reduction driven by the trailing edge piezoelectric fiber actuator, on the basis of the traditional independent variable pitch load reduction mode, which can make up for the shortcomings of the independent variable pitch load reduction mode and greatly improve the flexibility and reliability of load reduction of large wind turbines. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 A two-dimensional cross-sectional structure diagram of a wind turbine intelligent load reduction blade provided by an embodiment of the present invention;

[0017] Figure 2 A three-dimensional fragment structure diagram of a wind turbine intelligent load reduction blade provided by an embodiment of the present invention;

[0018] Figure 3 A three-dimensional fragment structure diagram of a wind turbine intelligent load reduction blade provided by an embodiment of the present invention;

[0019] Figure 4 A wind turbine intelligent load reduction blade circuit connection diagram provided by an embodiment of the present invention.

[0020] Description of reference numerals:

[0021] 1: blade skeleton; 11: blade leading edge; 12: leading edge panel; 121: first leading edge panel; 122: second leading edge panel; 13: main beam; 131: first main beam; 132: second main beam; 14: trailing edge deformation zone; 141: first trailing edge deformation zone; 142: second trailing edge deformation zone; 15: trailing edge; 2: main beam piezoelectric fiber actuator; 3: spring clip; 4: trailing edge piezoelectric fiber actuator; 5: slip ring; 6: web; 7: wire. DETAILED DESCRIPTION

[0022] The following is a further detailed description of a wind turbine intelligent load reduction blade and a working method thereof proposed by the present invention in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present invention will become more apparent from the following description and claims.

[0023] See also Figures 1 to 4 As shown, this embodiment provides a wind turbine intelligent load-reducing blade, including a blade skeleton 1 formed by sequentially connecting a blade leading edge 11, a leading edge panel 12, a main beam 13, a trailing edge deformation zone 14 and a trailing edge 15.

[0024] The leading edge panel 12 includes a first leading edge panel 121 and a second leading edge panel 122 arranged in pairs up and down. The blade leading edge 11 is a V-shaped bent piece. One end of the blade leading edge 11 is connected to the first leading edge panel 121, and the other end of the blade leading edge 11 is connected to the second leading edge panel 122.

[0025] The main beam 13 includes a first main beam 131 and a second main beam 132 arranged in pairs up and down, one is the main beam pressure surface, and the other is the main beam suction surface. The first main beam 131 is connected to the first leading edge panel 121, and the second main beam 132 is connected to the second leading edge panel 122. As a preferred example of this embodiment, the first main beam 131 and the second main beam 132 are laid with fiber composite materials, and the laying directions of the fiber composite materials of the first main beam 131 and the second main beam 132 are the same. As a preferred example of this embodiment, at least one web 6 is supported between the first main beam 131 and the second main beam 132. In this embodiment, two webs 6 are supported between the first main beam 131 and the second main beam 132, one is arranged near the leading edge end, and the other is arranged near the trailing edge end.

[0026] The trailing edge deformation zone 14 includes a first trailing edge deformation zone 141 and a second trailing edge deformation zone 142 arranged in pairs up and down, the first trailing edge deformation zone 141 is connected to the first main beam 131, the second trailing edge deformation zone 142 is connected to the second main beam 132, the free end of the first trailing edge deformation zone 141 and the free end of the second trailing edge deformation zone 142 are connected by the trailing edge 6, in this embodiment, the first trailing edge deformation zone 141 and the second trailing edge deformation zone 142 are close to the trailing edge and are connected to the trailing edge 6. As a preferred example of this embodiment, the first trailing edge deformation zone 141 and the second trailing edge deformation zone 142 are filled with flexible materials, such as silica gel and pearl cotton.

[0027] Several groups of main beam piezoelectric fiber actuators 2 are respectively laid in the first main beam 131 and the second main beam 132 along the span direction of the blade. In the present embodiment, the main beam piezoelectric fiber actuators 2 are laid in the fiber composite material interlayer of the first main beam 131 and the second main beam 132. The main beam piezoelectric fiber actuators 2 laid in the first main beam 131 and the second main beam 132 have the same deformation characteristics under the same driving voltage, including deformation direction, deformation angle, etc.

[0028] A spring clip 3 is provided on the trailing edge side of the main beam 13, and the two free ends of the spring clip 3 are respectively connected to the first main beam 131 and the second main beam 132, and the two clips of the spring clip 3 are respectively attached to the inner side walls of the first trailing edge deformation zone 141 and the second trailing edge deformation zone 142, and the clamping portion of the spring clip 3 is inserted between the first trailing edge deformation zone 141 and the second trailing edge deformation zone 142, and the clamping portion of the spring clip 3 is clamped with a plurality of groups of trailing edge piezoelectric fiber actuators 4 along the blade span direction.

[0029] A slip ring 5 is installed at the root of the blade. The slip ring 5 is electrically connected to several groups of main beam piezoelectric fiber actuators 2 through wires 7. The slip ring 5 is electrically connected to several groups of trailing edge piezoelectric fiber actuators 4 through wires 7. In this embodiment, the slip ring 5 adopts a multi-way slip ring.

[0030] The present embodiment provides an intelligent load-reducing blade for a wind turbine, and its working method is as follows: when the inflow wind speed of the wind turbine exceeds the rated wind speed, the force on the blade increases and the blade bends and deforms, and the first main beam and the second main beam undergo bending-torsion coupling deformation, and the blade is twisted and deformed while bending, thereby reducing the blade angle of attack and the speed of the wind rotor. At this time, if the speed of the wind rotor cannot drop to the rated speed value, the main beam piezoelectric fiber actuator is controlled to drive the first main beam and the second main beam to increase deformation and reduce the angle of attack, and the trailing edge piezoelectric fiber actuator is controlled to drive the trailing edge to deform toward the suction surface, thereby reducing the lift of the blade and further controlling the speed of the wind rotor.

[0031] The load reduction of the wind turbine can be achieved by simultaneously or in a certain order by using a main beam piezoelectric fiber actuator to drive the main beam to deform and reduce the load, and by using a trailing edge piezoelectric fiber actuator to drive the trailing edge to deform and reduce the load.

[0032] The present embodiment provides an intelligent load reduction blade for a wind turbine, comprising a blade skeleton formed by a leading edge of a blade, a leading edge panel, a main beam, a trailing edge deformation zone and a trailing edge connected in sequence, a plurality of groups of main beam piezoelectric fiber actuators are respectively laid in the first main beam and the second main beam along the span direction of the blade, a spring clip is arranged on the trailing edge side of the main beam, two free ends of the spring clip are respectively connected to the first main beam and the second main beam, a clamping portion of the spring clip is inserted between the first trailing edge deformation zone and the second trailing edge deformation zone, and a plurality of groups of trailing edge piezoelectric fiber actuators are clamped on the clamping portion of the spring clip along the span direction of the blade, and the present embodiment arranges piezoelectric fiber actuators at key positions of the main beam and the trailing edge, so that the blade adds three active and passive load reduction modes, namely, main beam bending-torsion coupling load reduction, main beam deformation load reduction driven by the main beam piezoelectric fiber actuator, and trailing edge deformation load reduction driven by the trailing edge piezoelectric fiber actuator, on the basis of the traditional independent variable pitch load reduction mode, which can make up for the shortcomings of the independent variable pitch load reduction mode and greatly improve the flexibility and reliability of load reduction of large wind turbines.

[0033] The embodiments of the present invention are described in detail above in conjunction with the accompanying drawings, but the present invention is not limited to the above embodiments. Even if various changes are made to the present invention, if these changes fall within the scope of the claims of the present invention and their equivalents, they still fall within the protection scope of the present invention.

Claims

1. A wind turbine intelligent load reduction blade, characterized in that: A blade skeleton comprising a blade leading edge, a leading edge panel, a main beam, a trailing edge deformation zone and a trailing edge connected in sequence, wherein the leading edge panel comprises a first leading edge panel and a second leading edge panel arranged in pairs up and down, one end of the blade leading edge is connected to the first leading edge panel, and the other end of the blade leading edge is connected to the second leading edge panel, the main beam comprises a first main beam and a second main beam arranged in pairs up and down, the first main beam is connected to the first leading edge panel, the second main beam is connected to the second leading edge panel, the trailing edge deformation zone comprises a first trailing edge deformation zone and a second trailing edge deformation zone arranged in pairs up and down, the first trailing edge deformation zone is connected to the first main beam, the second trailing edge deformation zone is connected to the second main beam, and a free end of the first trailing edge deformation zone and a free end of the second trailing edge deformation zone are connected by the trailing edge; A plurality of groups of main beam piezoelectric fiber actuators are respectively arranged in the first main beam and the second main beam along the blade span direction, a spring clip is arranged on the trailing edge side of the main beam, two free ends of the spring clip are respectively connected to the first main beam and the second main beam, a clamping portion of the spring clip is inserted between the first trailing edge deformation zone and the second trailing edge deformation zone, and a plurality of groups of trailing edge piezoelectric fiber actuators are clamped on the clamping portion of the spring clip along the blade span direction; A slip ring is installed at the root of the blade, and the slip ring is electrically connected to several groups of the main beam piezoelectric fiber actuators respectively, and the slip ring is electrically connected to several groups of the trailing edge piezoelectric fiber actuators respectively.

2. The wind turbine intelligent load reduction blade according to claim 1, characterized in that: At least one web is installed between the first main beam and the second main beam.

3. The wind turbine intelligent load reduction blade according to claim 1, characterized in that: The first main beam and the second main beam are laid with fiber composite material layers, and the fiber composite material layers of the first main beam and the second main beam are laid in the same direction.

4. The wind turbine intelligent load reduction blade according to claim 1, characterized in that: The first trailing edge deformation zone and the second trailing edge deformation zone are filled with flexible material.

5. The wind turbine intelligent load reduction blade according to claim 4, characterized in that: The flexible material is silica gel or pearl cotton or a combination of the two.

6. A working method of a wind turbine intelligent load reduction blade, characterized in that: Applicable to the wind turbine intelligent load reduction blade according to any one of claims 1 to 5; When the wind speed at the inflow of the wind turbine exceeds the rated wind speed, the blades are subjected to increased force and bend and deform, and the first main beam and the second main beam undergo bending-torsion coupling deformation, which causes the blades to twist while bending, thereby reducing the blade attack angle and the rotor speed; If the wind wheel speed cannot drop to the rated speed value, the main beam piezoelectric fiber actuator is controlled to drive the first main beam and the second main beam to increase deformation and reduce the angle of attack, and the trailing edge piezoelectric fiber actuator is controlled to drive the trailing edge to deform toward the suction surface, thereby reducing the lift of the blade and further controlling the wind wheel speed.

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