FI121128B - Directional braking equipment in a wind turbine - Google Patents

Description

FIELD OF THE INVENTION FIELD OF THE INVENTION

The invention relates to an apparatus for rotating a supported motor housing, i.e. a nacelle and a rotor attached thereto, at the upper end of the mast of a wind turbine 5 about an axis in the direction of the mast. More particularly, the invention relates to a directional braking device for braking a pivoting movement and locking the direction of the nasal.

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BACKGROUND OF THE INVENTION

The basic structure of the wind turbine consists of a support housing at the top of the mast, called a nacelle and an associated rotor with wings. The naselle is mounted at the top of the mast 15 so that the naselle can be pivoted in a plane perpendicular to the mast about an axis of rotation to direct the rotor in the desired direction relative to the wind. In order to effect the swinging movement, a typical structure has a gear ring supported at the upper 20 ends of the mast and one or more electric motor driven gear wheels adapted to rotate the tooth mask ring, respectively.

In order to stabilize the rotation of the nasal and to * * stop the rotation and lock the nasel into its desired position, • · · · · · · · · · · · · · · · · · · · · · · · · · · · ·.

: Usually the directional brake is implemented in the disc arrange- ··· jV; tea with the brake disc supported on the mast frame. Jarru- • ·. ·· *. the brake inlets are fitted around the periphery of the disc, • · · 30 each with opposite sides of the brake disc ... the actual brake pads. The brake caliper has at least • · one brake cylinder where the movable piston allows the brake pads to be pressed toward each other to squeeze the brake disc *: * between them. The movement of the piston is usually »··· 35 normally supplied via hydraulic fluid by means of a pressure applied to the brake cylinders.

·· «···· ♦ •« 2

Pressing the pad on the pad against the pad produces a braking force which is proportional to the friction coefficient between the pad and the pad, and 5 the force applied to the pad. Therefore, the higher the friction coefficient, the greater the braking force. However, if the coefficient of friction is too high, and in particular uneven in position (on the brake disc) and over time, the coefficient of friction can also cause a problem; The brake pad and brake-10 disc may become suddenly and momentarily staggered relative to one another, even if the speed of rotation of the nasal is still relatively high prior to engagement. However, the high inertia and the kinetic energy of rotation 15 of the mass rotating about the mast axis, and any minor elasticities and changes in the parts of the disc brake and associated structures, cause the brake pad and disc to release suddenly, new-20th indent. This can result in a series of successive grips and releases. In this case the so-called. "Slip-stick" phenomenon. This problem is particularly likely to occur in the case of large braked masses, such as in the case of a wind turbine directional brake, '**' · 25, which seeks to brake the rotational movement of a large and mass • · ·. In addition, braking and partial friction coefficient • · ·; thermal changes caused by unevenness • in the various parts of the brake system may increase the "slip-stick" - • · ·. ···. 30 probability of occurrence.

• · The "Slip-stick" phenomenon in the wind turbine ... causes heavy mechanical stress on the directional brake and other parts • • * ··· * associated with it, as well as the entire wind turbine. For example, this phenomenon can cause the entire mast to crumble at the rate of seizures and detachments. Toi- • · · ·. ···. Serious "slip-stick" effects on wind turbines and especially on their environment are the noise caused by 3 phenomena. Typically, the phenomenon produces loud bang-like and / or beat-up repetitive noises. From the high mast, the sound flows far and wide into its surroundings.

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PURPOSE OF THE INVENTION

It is an object of the invention to provide a novel type of wind turbine directional brake apparatus which provides relief from the above described problems.

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SUMMARY OF THE INVENTION

The directional braking apparatus according to the invention in a wind turbine is characterized by what is set forth in claim 1.

The method of manufacturing the friction member for a wind power steering brake device according to the invention is characterized in what is set forth in claim 8.

The invention relates to a directional braking device 20 in a wind turbine comprising a mast and a nozzle supported at the top of the mast with a rotor connected to the nacelle, the nacelle being pivotable about a mast perpendicular to the mast ·; ··· . ···. or nacelle-braked brake disc • · * 'I and a nacelle or mast-mounted braking unit with a braking unit • · · * · 1 · 1 including a friction pad with contact surfaces and a power unit · * ... '30 to press the contact surface of the friction member against the surface of the brake disc to resist the swinging movement of the actuator by frictional force. Hardware · · · ·: 1 ·: The contact surface included in the friction member comprises graphite-containing areas, between the contact surface and the brake disc ** to reduce its friction coefficient.

• · • · ··· • · · · · «« · 4

The method of making a friction member for a wind turbine deflector assembly according to the invention, comprising a contact surface that can be pressed against a shim disk included in the deflection assembly, comprises the following steps; making a cavity on the contact surface of the friction member, preparing an alloy containing graphite powder and resin material, introducing the alloy into the cavity and forming the alloy to form part of the contact surface of the friction member, and curing the alloy to seal the graphite powder.

The directional brake apparatus of the invention includes a brake disc which is immobilized with respect to the mast or nacelle about a axis of rotation and a brake unit which is immobilized with respect to the nacelle or mast respectively. In other words, one of the brake discs and the brake unit is stationary relative to the mast and the other relative to the nacelle, so that as the nacelle turns 20 they move relative to one another. The brake disc may be mounted e.g. on the perimeter of a mast frame, whereby the brake unit would be attached to a nacelle. The brake disc is typically a disc-shaped ring disc spreading in a plane perpendicular to the axis of rotation. It is also possible that the brake disk is a rotating axis • ·: a rim-like structure whose rim width • · · coincides with the axis of rotation. In this case, the contact surface of the friction member could e.g. be substantially • · ·; V: parallel to the direction of the axis of rotation.

• ·. ···. 30 The brake unit includes at least one friction • · · element and a power unit for pressing the contact surface of the friction element against the brake disk in response to the • • *** rotation of the nasal. friction force. There may be several friction members, and the friction members may be arranged, for example, • J1 35 in pairs on opposite sides of the brake disc, so that the brake disc is pressed when the brake is applied. between the friction members. The power units may be, for example, only one on either side of the disc, whereby the force is transmitted to any other friction member by means of a connecting member extending around the edge of the brake disc, similarly to the car brake disc 5.

When the contact surface of the friction member is pressed against the surface of the brake disc by means of a power unit, the frictional force between the brake disc and the friction member tends to brake the movement between the brake unit and the pin and the mast of the wind turbine. The graphite-containing areas of the contact surface reduce the coefficient of friction between the contact surface and the brake disc, which prevents the occurrence of the "slip-stick" phenomenon and consequent indirect effects, even at high compressive forces applied to the friction member of the power unit. During braking, as the contact surface slides over the brake disc, the friction between the contact surface and the brake disc consumes graphite-containing areas such that the graphite additionally releases graphite pairs between the contact surface and the brake disc, which keeps the friction coefficient low and smooth. This further prevents the "slip-stick" phenomenon.

In one embodiment of the invention, the areas containing the graphite • ·: · ♦ * are located at the front and / or the rear of the contact surface relative to the direction of the rotating nacelle circumferential velocity vector. In one embodiment of the method of the invention, the contact element of the friction member is made. 30 to the front and / or rear of the contact surface with respect to the direction of the · rotating nacelle peripheral velocity vector.

... By positioning the graphite containing areas with the • · * ··. in this way, the formation of a "slip-stick" phenomenon on the contact surface can unexpectedly be more effectively prevented. This may be *: * 35 possibly due to the tendency of the phenomenon to form a concern «···; ***; at the front of the mounting surface where the brake disc slides • · · *. under the surface. In addition, as the graphite particles release, the graphite-containing areas at the front of the contact surface 6 release the released particles to move substantially beneath the contact surface, thereby affecting the particle's friction coefficient smoothing effect on almost the entire contact surface. In order for the "slip-stick" effect to work when rotating the nail in either direction, the graphite-containing areas can be located at both ends (front and rear) of the contact surface.

In one embodiment of the invention, the total surface area of the graphite-containing areas on the contact surface is up to 10 percent of the total surface area of the contact surface. In one embodiment of the method of the invention, the recesses do not represent more than 10% of the total contact surface area. Keeping the total area of the graphite-containing areas small enough allows for a sufficient braking force to be obtained even with a small force of the power unit.

In one embodiment of the invention, the surface contact comprises graphite-containing regions such that the projection of the regions perpendicular to the direction of the rotating nacelle peripheral velocity vector covers at least 50% of the contact surface width in this * * 25 direction, wherein the graphite-containing regions affect at least approximately 50% of the area of the brakes over which the contact surface slides; · *: When reversing the brake. By placing the areas containing the graph ··· phytes in the manner mentioned above, the · · · ·. 30 ensure that most of the friction member's contact surface is · · · · * 'perpendicular to the sliding direction of the contact surface, and no part of the contact surface is thereby significantly affected ·; · 35 "slip-stick" effects.

····. ***. In one embodiment of the invention, graphite • · ··· ·. areas containing graphite powder bonded to · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · Binding the graphite powder to the resin material prevents the powder from leaking into the cavities of the brake disc in an uncontrolled manner. During braking, as the contact surface slides over the brake disc, the friction between the contact surface and the brake disc consumes graphite-containing areas so that the bonded graphite powder effectively separates the graphite particles between the contact surface and the brake disc, keeping the friction coefficient in the case of the contact surfaces of the friction members. This further prevents the "slip-stick" phenomenon.

In one embodiment of the invention, the graphite-containing regions are located at a distance from the other and at a distance from the edges of the contact surface to improve the tensile strength of the friction member. In one embodiment of the method of the invention, more than one cavity is formed at a distance from one another and at a distance from the edges of the contact surface to improve the breaking strength of the friction member.

In one embodiment of the invention, the surface area parallel to the contact surface of the graphite-containing regions is substantially constant through the entire friction member in a direction perpendicular to the contact surface of the friction member.

• · • · ·: 25 The surface area of phytate-containing areas during braking during braking does not therefore: # ϊφί change substantially and the characteristics of the contact surface remain substantially the same.

• ·. ** ·. In one embodiment of the method of the invention, the cavity is a hole extending through the friction member. Making a notch through the friction member can facilitate • · introduction of a graphite powder and resin-containing compound into the notch.

> # * i * The above embodiments of the invention: ***: 35 can be freely combined with one another. Multiple • · · embodiments can be combined into a new embodiment ** · *. form. The method or apparatus to which the invention relates may include one or more of the above embodiments of the invention.

DETAILED DESCRIPTION OF THE INVENTION

The invention will now be described, by way of example, with reference to the accompanying drawings, in which:

Figure 1 is a schematic cross-sectional view of a prior art wind turbine,

Figure 2 is a schematic cross-sectional view of a prior art 10 wind turbine directional braking system,

Figure 3a is a schematic cross-sectional view of a friction member of a directional brake device according to the invention, Figure 3b is a schematic view of a friction member of a directional brake device according to the invention, and

Figure 4 is a flowchart illustrating an embodiment of the method of the invention for manufacturing a friction member for a wind turbine oral brake system.

For simplicity, the following examples refer to parts of the invention. . are considered the same for repetitive parts.

• · · **;. * 25 Figure 1 shows a wind power plant erected on the ground with a vertical mast 2 • · · in the upright position and a supporting housing, naselle 3, • · *. · Mounted on rotor 4 with wings 5. Naselli • · · t: is mounted for pivoting about an imaginary axis 6 of the longitudinal mast 30 so that the rotor 4 can always be directed towards the wind or otherwise in the desired direction with respect to the wind. In order to stop the rotation • ♦ • and lock nacelle 3 in the desired direction «·«, wind turbine 1 has a directional control system 7. As shown in the sectional view of 35 nacelle 3 and mast 2, 35 braking system 7 inside mast 2 mast frame • · 9 rotating stationary braked disc 8, and nacelle 3 stationary rotating braking unit 9 rotating about the inside of brake disc 8, which rotates with the rotor of the brake disc 8 y.

The operation of the brake unit 9 of the prior art directional braking device 7 will be explained in more detail by the example shown in Figure 2. 2, two or more hydraulic cylinders 10 on opposite sides of brake disc 8 10 are aligned with the brake system 7. The hydraulic cylinders 10, which are perpendicular to the plane of the brake disc 8, have a piston 11 in each of the hydraulically actuated cylinders. a separate friction member 12 on both sides of the brake disk 8, sliding against the brake disk 8, forming a friction force 12, parallel to the periphery of the brake disk 8 (and possibly the surface of the brake disk 8) relative to the brake unit 9. When a sufficiently high pressure from the hydraulic system (not shown) is introduced into the sy-20 cylinder 10 through the pressure channel 13 provided on the body of the brake unit 9, the pistons 11 are depressed. towards each other, squeezing the brake disc 8 between the friction members 12. This produces a frictional force that brakes • · ·: 25 pivoting movements of the 3 nacelles relative to the mast 2.

The contact surface 14 of the friction member 12 according to an embodiment of the invention is shown in Figure 3a. The contact surface 14 is that part of the friction member 12 which presses. leans against the brake disc 8 when braking. The contact surface 14 of Fig. 3a • · · 30 comprises graphite-containing regions 15. The regions 15 are located in this example. the dotted arrow 18 direction of the contact surface of the front and rear. The dashed arrow 18 reflects the sliding - *: * of the contact surface 14 with respect to the brake disk 8 during braking. Si-: ***: 35 by aligning areas 15 to the front and back of the touch surface • · · *. • · · ··· * as a result of the slip-stick phenomenon. which is surprisingly more effective in preventing. This is probably due to the tendency of the phenomenon to form at the front of the contact surface where the brake disc 8 slides under the contact surface. In this case, any impurities, temperature differences, unevenness of the surface of the brake disc 8 or other factors causing the kink coefficient of the kit between the brake disc 8 and the contact surface 14 are first to be exposed to the front of the contact surface 14 when the nacelle 3 brakes. In this case, it is essential to smooth out the friction coefficient variations caused by the inhomogeneities of, for example, the brake disc 8 at the front of the contact surface 14. In addition, as the graphite particles release from the graphite-containing areas 15 at the front of the contact surface 14, the released particles move substantially under the entire contact surface 14, whereby the "lubricating" effect of the particle smoothing friction coefficient is applied to the entire contact surface. when braking the nacelle 3 in either direction, the graphite-containing areas 15 may be located at both ends (front and rear) of the contact surface 14, as shown in Figure 3a.

In addition, in the contact surface 14 of the friction member 12 shown in Figure 3a, regions 15 are disposed such that the projection of the regions perpendicular to the sliding direction of the contact surface (· arrow 18) covers: more than 50 percent of the total contact surface width. Projection of areas 15 to said dotted lines 17 • ·. · * ·. 3a • · · · · 30 with broken projection lines 16. The total length of the dashed lines ... 17 thus covers more than 50% of the total width of the contact surface 14 in the direction defined by the dashed lines 17 in FIG. perpendicular to the sliding direction (arrow 18). By positioning the graphite-containing areas · · · on the contact surface 15 as mentioned above, it is ensured that the slip-stick effect is · · 11 directed against most of the contact surface of the friction member, in a direction perpendicular to the sliding direction of the contact surface (arrow 18). thus, there is no significant effect on the "slip-stick" effect of the contact surface 14. Also, the spreading of graphite particles and the "lubricating effect" they cause to the area of the contact surface 14 can be enhanced by the aforementioned positioning of the areas 15.

In the contact surface 10 of the friction member 12 shown in Figure 3a, the graphite-containing areas 15 are formed at a distance from each other and the edges of the contact surface 14 to maintain sufficient tensile strength of the contact surface 14 and friction member 12 for use in harsh wind conditions. It should also be noted that in the contact surface 14 of Figure 3a, the areas 15 having a lower friction coefficient than their surroundings have a small total area of less than 10 percent of the total area of the contact surface 14. In this way, the mean coefficient of friction 20 of the contact surface 14 can be kept high enough to effectively stop the rotation of the nacelle 3.

Fig. 3b is a cross-sectional view of the friction member 12 of Fig. 3a, where it is noted that the areas 15 containing graffiti may extend homogeneously throughout the friction member 12. Thus, during the braking of the contact surface 14 during the braking, the surface area of the areas 15 does not change substantially and the characteristics of the contact surface 14 remain substantially the same.

• ♦. ···. Fig. 4 is a flowchart for the method of making a friction member 12 according to the invention. In the first step of the method, a socket is formed on the contact surface 14 of the friction member 12. The cavity may * * be manufactured e.g. through the entire friction member 12 as shown in Fig. 3b. The total surface area of the cavities is ····. * · *. On 35 surfaces, 14 covers up to 10% of the contact surface. nan 14 total areas. The cavities are further prepared at such locations at the contact surface of the friction member 12 that the graphite-containing compound to be prepared in the cavities at a later stage forms graphite-containing areas 15 at the contact surface 14 shown above and in Figure 3a.

In step S2, an alloy containing graphite powder and resin material is prepared. The compounding agent may be prepared, for example, by adding a little epoxy resin to the graphite powder, which is as clean as possible, free of oil or solvents, to bind the graphite powder to the epoxy resin. The purpose of the epoxy resin is to prevent graphite powder from freely leaking out of the cavities at the contact surface 14 of the friction member 12. In step S3, the compound is introduced into the cavity and molded into the contact surface 14. placed so that the contact surface 14 is against the plane, after which the alloying agent can e.g. be poured into the recess on the side opposite to the contact surface 14 of the friction member 12. The dopant may be compressed to a compact mass in the cavity and then the resin material in the dopant may be cured (step S4).

'* The invention is not limited to the above precursors, but its embodiment may freely vary within the scope of the claims.

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Claims (12)

1. Directional braking device (7) in a wind turbine (1), the wind turbine (1) comprising a mast (2) and a nacelle (3) supported by an upper end of the mast (2) with rotors (4) connected to the nacelle (3); in a plane perpendicular to the mast (2) about the axis of rotation (6) parallel to the mast (2), wherein the directional braking device (7) includes a brake disc (8) which is immobilized relative to the mast (2) or na-10 Sell (3); a brake unit (9) which is immobilized with respect to a nacelle (3) or a mast (2), the brake unit (9) having a friction member (12) with contact surfaces (14) and a power unit for pressing the contact surface (14) on the friction member (12); (8) surface for counteracting the pivoting movement of the pin (3) by frictional force, characterized in that the contact surface (14) included in the friction member (12) comprises graphite-containing areas (15), a contact between the contact surface (14) and the brake disc (8). to reduce the odds. Directional braking device (7) according to Claim 1, characterized in that the graphite-containing areas (15) are located on a rotating nail gun. (3) with respect to the direction of the peripheral velocity vector • · · * “. * 25 (14) front and / or rear. A directional apparatus (7) according to any one of claims 1 to 2, characterized in that the graphite-containing areas (15) the total surface area of the contact surface (14) is not more than 10% of the total area of the 30 surface surfaces (14). , 1; Directional brake device (7) according to one of Claims 1 to 3, characterized in that the contact surface (14) has graphite-containing regions (15) such that regions (15) ) projection to the direction of the · · · · ... · 35 circumferential velocity vector of the small cell (3) .i. perpendicularly to at least 50% of the width of the contact surface (14) in this direction, where the graphite-containing areas (15) affect at least about 50% of the area of the brake disc (8) over which the contact surface (14) slides. 3) when reversing the brake. Directional brake device (7) according to one of Claims 1 to 4, characterized in that the graphite-containing areas (15) contain graphite powder bonded to the resin material. Directional guidance apparatus (7) according to one of Claims 1 to 5, characterized in that the graphite-containing areas (15) are spaced apart and spaced from the edges of the contact surface to improve the tensile strength of the friction member (12). Orientation device (7) according to one of Claims 1 to 6, characterized in that the surface parallel to the contact surface (14) of the graphite-containing areas (15) is substantially constant through the entire friction member (12) to the contact face 20 (14). ) in a perpendicular direction. A method for manufacturing a friction member (12) for a wind turbine deflector assembly (7), the friction member (12) comprising: a contact surface (14) pressed against a brake disk (8) of the deflection assembly (7). , characterized in that the process comprises the step of: -: - making a cavity on the contact surface (14) of the friction member (12), - · - producing a graphite powder and a resin-based alloying compound ... - 30 alloying agent in the cavity and shaping • · • · * '*. an alloy such that the alloy is formed as a part of the contact surface of the friction member (12) *: * (14), and • · · ·: 1; 35 - curing the alloying agent to bind graphite powder closely to the resin material. ··· 2 • · 2 Method according to Claim 8, characterized in that more than one cavity is produced at a distance from one another and at a distance from the edges of the contact surface (14) to improve the breaking strength of the friction member (12). Method according to one of Claims 8 to 9, characterized in that the cavity is a hole extending through the friction member (12). Method according to one of Claims 8 to 10, characterized in that the recesses do not represent more than 10% of the total area of the contact surface (14). Method according to one of Claims 8 to 11, characterized in that a notch is made on the contact surface (14) of the friction member (12) with respect to the direction of the peripheral velocity vector of the pivotable nozzle (3). • · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · · ·room ·room leave leave • • • • • • • • • • • • • • • • • • • • • • • • • • • • 2