DE102011056980A1 - Wind turbine - Google Patents

Abstract

The invention relates to a wind turbine with a rotor rotatable about a vertical axis of rotation (11) with at least one wind flap (50) which can be pivoted out of a rest position in one direction about a horizontal axis (51). The wind turbine is characterized in that the rotor in the direction of the vertical axis of rotation (11) is movable. The invention further relates to a method for operating such a wind turbine.

Description

The invention relates to a wind turbine with a rotatable about a vertical axis of rotation rotor with at least one wind flap, which is pivotable from a rest position in a direction about a horizontal axis.

Wind power has been technically exploited for many centuries. In the preindustrial era, in addition to hydropower, it represented an energy potential that could not otherwise be achieved. First of all, displaced by power machines, wind power use has experienced a renaissance in recent decades, in particular for regenerative power generation. For this purpose, the windmills are mainly used with aerodynamically shaped wings and horizontal axis of rotation. Individual wind turbines of this type achieve performances in the megawatt range. The advantage here is that the performance of the wind turbine can be relatively easily via a rotation of the blades along its longitudinal axis, also called blade adjustment, adapted to different wind conditions. About this pitch adjustment, the wind turbine can also be done from damage in strong winds or storms. A disadvantage of wind turbines with a horizontal axis, however, is that the orientation of the axis must be in the wind direction, to which a tracking device is required. This complicates in particular the use of such wind turbines with lower power, for example in the form of a privately operated small plant for decentralized renewable energy production for own use and / or for feeding into a power grid.

In addition to the aforementioned wind wheels with horizontally aligned axis those with vertical axis are known, which are independent of the wind direction without further active control. The so-called Darrieus systems, while also have aerodynamically shaped blades, which use a buoyancy force. Of these, the wind turbines of the type mentioned above, in which are provided about a horizontal axis pivotally mounted wind flaps, which are pushed away by the wind due to their air resistance. The fact that the wind flaps are pivotable out of a usually substantially vertical rest position only in one direction, they set against their wind resistance to movement with the wind, whereas they move on the wind from the vertical rest position out into a substantially horizontal Pivoting position and can be moved with less air resistance to the wind. Upon further rotation into the wind direction they turn into the vertical starting position and are moved on by the wind.

Based on this basic principle wind turbines are independent of the wind direction, but they are difficult to adapt to different wind conditions. From the publication DE 2401214 A1 is to protect against destruction in too strong wind speed limitation by a centrifugal force controlled braking device known. Although this protects moving elements, such as the rotating rotor and connected generators for power generation against excessive, destructive speeds, it does not protect the wind turbine as such, however, from the high wind load associated with the strong wind.

Object of the present invention is therefore to provide a wind turbine of the type mentioned above, which can be easily adapted to different wind conditions and thus in particular can be protected against excessive wind loads. It is another object to provide a method for safely operating a wind turbine.

This object is achieved by a wind turbine and an operating method for a wind turbine with the features of the independent claims. Advantageous embodiments and further developments are the subject of the respective dependent claims.

A wind turbine according to the invention of the type mentioned above is characterized in that the rotor is movable in the direction of the vertical axis of rotation. Usually, the wind speed in the ground area is lower than in more exposed heights. The variation of the height of the rotor achieved by the method of the rotor in the vertical direction thus has a speed regulating effect. Too high speeds, which are to be avoided because of the large occurring centrifugal forces on the rotor and the increased load on bearings can be prevented without a mechanical brake so. In addition, by lowering the rotor and the wind load is lowered to the wind turbine, which prevents damage. The fact that the rotor can be lowered or raised, also the installation of the wind turbine and its maintenance is simplified.

In an advantageous embodiment of the wind turbine, a windshield is provided which completely or partially surrounds the rotor in a lowered vertical position. By the windbreak, the effect of lowering the rotor is additionally supported.

An inventive method for operating a wind turbine with a rotatable about a vertical axis of rotation rotor is characterized in that the rotor depending on its measured speed is moved in a vertical direction. In an advantageous embodiment of the method, the rotor is moved depending on a measured wind speed in the vertical direction. Speed and wind speed are suitable criteria to automatically set the height of the rotor, which is always safe operation of the wind turbine is given.

The invention will be explained in more detail by means of exemplary embodiments with the aid of three figures. Show it:

1 a schematic sectional view of a wind turbine in a first embodiment,

2 a schematic sectional view of a wind turbine in a second embodiment and

3 a schematic sectional view of a wind turbine in a third embodiment.

1 shows a first embodiment of a wind turbine in a schematic sectional view, the section is executed here vertically and centrally through the wind turbine.

The wind turbine has a central vertical mast as a supporting element 10 on. This is anchored in a foundation, not shown here in the ground or alternatively can be erected on a preferably movable, for example, mobile, platform. The mast 10 For example, it may be a carbon fiber tube, but other materials such as aluminum or steel, especially stainless steel, may be used. The cross section of the mast is preferred but not necessarily round. The longitudinal axis of the mast 10 represents a vertical axis of rotation 11 for the wind turbine

Concentric to the mast 10 is a support cylinder 30 arranged, which has one with the mast 10 cooperating vertical guide 12 in the direction of the vertical axis of rotation 11 on the mast 10 is vertically movable. The vertical guide 12 may be a sliding guide, in the corresponding sliding elements, such as plastic or bronze on corresponding surfaces of the mast 10 glide along. Roller bearings or recirculating ball bearings can also be used in the vertical guide 12 be used.

The wind turbine has a lifting device 20 on, by means of which the support cylinder 30 can be moved vertically. In the illustrated embodiment of the 1 is the lifting device 20 in the mast 10 integrated and includes a lifting cylinder 21 and a hydraulically or pneumatically movable lifting rod 22 , The lifting cylinder 21 is with the mast 10 or connected to the aforementioned foundation, where against the lifting rod 22 on a crossbeam 23 acts, with the support cylinder 30 connected is. The crossbeam 23 is on two opposite sides through the side wall of the mast 10 guided, which has corresponding vertical slot-shaped openings to a vertical movement of the cross member 23 to enable. In addition to the illustrated hydraulic or pneumatic lifting device 20 Alternative lifting devices are possible, for example in the form of a rope or chain drive, in which a by a winch electric motor driven traction cable or a chain through the mast 10 or runs along it and at the top of the mast 10 is guided over a pulley. With its free end is the pull rope or the chain with the support cylinder 30 connected. It is also conceivable a lifting device whose drive on the support cylinder 30 is moved, and in the example of a gear or friction wheel with a rack or a friction surface on the mast 10 interacts.

Next is a rotary cylinder 40 provided, concentric with the support cylinder 30 around this by pivot bearing 31 is rotatably mounted. Exemplary are in the 1 two pivot bearings 31 in each case in the region of the upper or lower end of the support cylinder or rotary cylinder 40 are positioned. The support cylinder 30 and the rotary cylinder 40 have approximately the same height, which in turn in the example shown about half the height of the mast 10 is.

Between the support cylinder 30 and the rotary cylinder 40 is a ring generator 32 arranged, the rotation of the rotary cylinder 40 opposite the support cylinder 30 generates an electric current. This is a stator of the ring generator 32 with the support cylinder 30 and a rotor of the ring generator 32 with the rotary cylinder 40 connected. The ring generator 32 serves the conversion of the wind energy acting on the wind turbine into electrical energy. Alternative to the ring generator 32 It is also possible to use a generator with a central axis of rotation. In that case, the generator is on the support cylinder 30 set and the axis of rotation is a gear, Reibrad- or belt drive with the rotary cylinder 40 coupled. It is also conceivable, the rotational movement of the rotary cylinder 40 to transmit to a relative to the foundation fixed generator via a shaft or other mechanical transmission.

From the rotary cylinder 40 have radially outward wind flaps 50 around a horizontal pivot axis 51 are pivotable in one direction. At the in 1 shown Embodiment form each more, here five, wind flaps 50 arranged one above the other a wind wing. Of these wind wings are two opposite in the 1 visible, in total, the embodiment has four wind blades, evenly around the rotary cylinder 40 are arranged around so that the angle between them is 90 degrees. Both the number of four wind blades, as well as the number of five wind flaps per wind vane in the illustrated embodiment are exemplary and not limiting. The number of wind wings may be different in other embodiments and is preferably between two and six, and more preferably is three or four. The number of wind flaps per wind wing may also vary in other embodiments, in particular it is also conceivable that a single wind flap 50 represents a wind wing. The rotary cylinder 40 and all associated with him and with him rotating elements, in particular the wind wings and the wind flaps 50 , are hereinafter collectively referred to as the rotor of the wind turbine.

In the example of 1 each wind vane is horizontally aligned and radially from the rotary cylinder 40 Outwardly facing outriggers 41 on, one in the upper and one in the lower part of the wind vane. At their outer ends are the upper and lower arms 41 each wind vane by a vertical strut 42 connected. Thus, a frame is formed for each of the wind wings, in which the five wind flaps 50 are used.

The wind flaps 50 are each in their upper part on one side in the rotary cylinder 40 and on the other side in the vertical strut 42 pivotally mounted, with their respective lower end either against a stop on the rotary cylinder 40 and / or the vertical strut 42 or at the underlying wind flap 50 rests, leaving the wind flaps 50 can only be pivoted in one direction. If wind comes from a direction on the wind wing, the wind flaps close 50 and the wing or the wind flaps 50 have a high wind resistance, and accordingly experience a wind pressure, which leads to a rotation of the rotary cylinder 40 leads. If the wind hits the opposite side of the wind vane, eg if the wind vane moves against the wind direction during rotation of the rotor, the wind flaps will pivot 50 on and the wind wing has a lower wind resistance. Consequently, regardless of the wind direction, a torque on the rotor, which causes its rotation in the wind. About the ring generator 32 This rotary motion can be converted into electrical energy.

The functioning according to this basic principle wind turbine first requires no active control, since the wind flaps 50 purely passive by the wind itself open or be swung.

During operation of the wind turbine, a speed of the rotor adjusts, which is dependent on the wind strength and depending on which resistance of the ring generator 32 the rotation of the rotary cylinder 40 contrary to load. If the wind strength is too high and / or the ring generator 32 Power can not give, for example, because downstream energy storage are filled and an energy delivery to a load or in a power supply network is not desired or provided, according to the application, the lifting device 20 can be used to lower the rotor. Usually, the wind speed in the ground area is lower than in more exposed heights. The variation of the height of the support cylinder 30 and thus rotor already has a speed regulating effect. Too high speeds are to be avoided because of the large occurring centrifugal forces on the rotor and the increased load on bearings. In addition, a high wind strength, especially when it hits in gusts, even due to excessive wind load regardless of the speed of the rotor damage to the wind flaps 50 and cause their pivoting mechanism and possibly also on other elements. Finally, there is a risk that the mast 10 breaks or breaks from its anchorage.

The lifting device 20 also simplifies the installation of the wind turbine and its maintenance. Smaller, privately-designed wind turbines often have heights as high as 20 meters or more to escape the slipstream of surrounding buildings or trees. By the lifting device 20 Can be used when setting up or servicing a crane or similar. be waived. This makes setting up easier or, for example, in an inaccessible area, only possible.

In the in 1 illustrated embodiment is also a windbreak 60 provided that provides slipstream for a lowered rotor. In the example shown is the windbreak 60 designed as an upwardly open, seated on the floor cylinder into which the rotor of the wind turbine can retract substantially completely. The windbreak 60 also prevents persons in the area of the rotor of the wind turbine can pass and thus reduces the risk of injury by the rotating rotor, especially if the wind turbine has not so high a height that touching the rotor alone is avoided. Thus, the proposed wind turbine is particularly well suited as a smaller system, for example for use on a private property, for example in a garden. It can be provided that the windbreak 60 removable Has elements or flaps or the like, so that in the lowered state of the rotor maintenance or repair work can be performed on this. The windbreak 60 provided slipstream reduces the risk of accidents during maintenance by a rotating rotor in the wind. In addition, of course, a locking mechanism is provided which prevents the rotation of the rotor.

The lifting device 20 is from one in the 1 not shown control device driven. It can be provided several factors to control the height of the rotor on the mast 10 to take into account. These factors may be, for example, the rotational speed of the rotor, which is determined by a rotational speed sensor, wherein in a suitable embodiment of the ring generator 32 this can be used as a speed sensor. Furthermore, a separately measured wind speed, for example measured by an anemometer, can be taken into account. Also predicted weather information, for example, based on a network connection, can be considered. Furthermore, a timer can be provided via a timer. Finally, a manual control option is given. In addition to the described lowering of the rotor at a high wind speed can be additionally provided to lower the rotor in calm or very low wind speed, so in cases where a wind energy use is not possible.

The windbreak 60 finally offers the possibility of further, complementary components of the wind turbine visible and theft-protected either on an inner wall of the windbreak 60 or be arranged in a lower region below a fully shut down rotor. Such components may, in particular, be system components, for example an inverter, that of the ring generator 32 supplied current into a suitable for feeding into a power grid compatible current of suitable frequency and phase. Furthermore, it is conceivable that energy storage devices are provided as system components which make the wind power plant usable as an energy supply system in an island location separate from a power supply network or which buffer energy in conjunction with a power supply network in order to feed it into the energy supply grid in times of increased demand. Batteries can be used, for example, as an energy store or else a device for the electrolysis of water and subsequent storage of the decomposition products hydrogen and oxygen. The decomposition products can be reacted with one another in fuel cells while supplying electricity. Even if a windbreak 60 is not provided, such system components can be integrated into the wind turbine, for example, in a foot or in a foundation of the wind turbine, are arranged.

2 shows a second embodiment of a wind turbine according to the application in a representation analogous to 1 , The same reference numerals in this and the following figure identify the same or equivalent elements as in FIG 1 ,

The wind turbine in turn has a rotor with a vertical axis of rotation 11 on, around which is a rotary cylinder 40 can rotate with radially outwardly facing wind blades. The rotor corresponds to that of the first embodiment. It is therefore based on the comments 1 directed.

It is a lifting device 20 present to move the rotor in height above the ground or foundation. The lifting device 20 is as before hydraulic or pneumatic with a lifting cylinder 21 and a reciprocating piston 22 executed. In contrast to the first embodiment, however, here is the reciprocating piston 22 Fixed to the foundation and the lifting cylinder 21 is movable. In addition, the reciprocating piston forms 22 at the same time a mast 10 the wind turbine and the lifting cylinder 21 represents a support cylinder 30 to that of the rotary cylinder 40 is rotatably mounted. An upper vertical guide 12 is stationary on the reciprocating piston 22 set and includes a seal for the operating medium of the lift cylinder 21 , for example, a Simmerring. A lower vertical guide 12 moves with the lift cylinder 21 With.

The arrangement is compact and material-saving and has the further advantage that when the rotor is lowered, the mast 10 does not stand up. In a further development of the illustrated embodiment, a multi-extendable lift cylinder, also called step or telescopic cylinder can be used.

3 shows a further embodiment of a wind turbine according to the application; unlike 1 in a horizontal sectional view.

It is again a vertical mast 10 provided on the guided by vertical guides 12 a support cylinder 30 can be moved up and down in the vertical direction. The vertical movement of the support cylinder 30 is achieved by a lifting device, here over three pull ropes 24 is realized. The ropes 24 are each on one side of the mast 10 guided along, run at its upper end via a pulley and are on the opposite side again to the support cylinder 30 brought down to which they are connected.

Concentric around the support cylinder 30 and rotatably mounted about this is a rotary cylinder 40 arranged, are distributed from the four radially evenly distributed around the circumference radially outward. The wind wings each have a respective horizontal pivot axis 51 swiveling wind flaps 50 on. The rotating about the vertical axis of rotation elements are collectively referred to again as the rotor of the wind turbine. As in the previously described embodiment, several wind flaps are preferred here as well 50 each arranged in several levels one above the other.

The wind flaps 50 are at one along the horizontal pivot axis 51 extending horizontal shaft 52 attached. There is a stop provided, a movement of each wind flap 50 from a substantially vertical rest position out only in one direction allows. This stop can be either on the wind flap 50 itself or on the horizontal wave 52 Act. Respective wind flaps 50 are coupled together so that they are about 90 ° from each other about the horizontal pivot axis 51 are twisted. This coupling supports the swiveling up of the wind flaps 50 , The coupling is achieved by a not visible in the figure control linkage, the levers 53 attacks, each on the horizontal waves 52 are arranged. In 3 are all wind flaps 50 therefore visible at about 45 ° from its vertical rest position. In this illustration it can be seen that the wind flaps 50 have no rectangular basic shape, but especially in the mast 10 curved are cut. It may collisions with in-plane adjacent wind flaps 50 be prevented.

To the wind flaps 50 around a supporting frame is formed, which is not visible in the figure horizontal arms and a vertical strut 42 is formed (see also cantilever 41 of the 1 ). The horizontal waves 52 are in camps at their ends 44a . 44c stored on the rotary cylinder 40 or on the vertical strut 52 are fixed. The the wind flaps 50 surrounding frame members, so the horizontal boom and the vertical strut 42 are preferably aerodynamically shaped, so that there is an additional torque in the direction of rotation of the rotor of the wind turbine.

To the rotary cylinder 40 is a wind deflector 43 running in an area between the wind flaps 50 the rotary cylinder 40 touched and by fasteners, such as screws, is attached to this. To the wind flaps 50 towards the wind deflector 43 from the rotary cylinder 40 spaced, with its maximum distance at the positions of the wind flap 50 reached. At these points openings are provided, through which the horizontal waves 52 are guided, preferably at these locations still another camp 44b in support of horizontal waves 52 is provided. In the area between the wind flaps 50 This results in a concave surface design of the wind deflector 43 , This is preferably not symmetrical, but provided on the respective side facing the winch with a lower pitch than on the side facing away from the wind. Due to the asymmetric shape design directs the wind deflector 43 also air currents on the masts 10 To run and would not lead to a torque on the wind-facing (closed) wind flap 50 , which is exposed to such an increased wind pressure, whereby the efficiency of the wind turbine increases.

In addition, it is possible with smaller wind turbines, on the outer storage of horizontal waves 52 and thus on the vertical strut 52 and also to abandon the horizontal boom, and the wind flaps 50 only over the inner of the rotary cylinder 40 or on the wind deflector 43 arranged bearings 44a , b pivotally set.

In the wind deflector 43 hidden area of horizontal waves 52 are in the illustrated embodiment also the lever 53 arranged, which is essentially parallel to the mast 10 running control linkage are actuated. This in turn can be moved by a further lifting cylinder or other drive means in its longitudinal direction, whereby the pivot angle of the wind flaps 50 can be set. In this way can supportive or alternatively to the passive pivoting of the wind flaps 50 around the pivot axis 51 an active adjustment of the wind flaps 50 be performed. An active pivoting of the wind flaps 50 has the advantage in low wind, that the windcaps running against the wind 50 can be placed in a completely horizontal or downwind position and so they offer the wind when counterflow the lowest possible wind resistance.

A likewise supportive effect for the complete raising of the wind flaps 50 offer auxiliary flaps 54 , one of each on each of the horizontal waves 52 is arranged. The auxiliary flaps 54 are like the wind flaps 50 asymmetric on the horizontal waves 52 attached so that incident wind creates a torque on the horizontal shafts 52 by which they are turned and the wind flaps 50 swing open. The auxiliary flaps 52 However, they are so twisted against the wind flaps 50 connected with them, that they with respect to the swinging the wind flaps 50 lag and the greatest torque on the horizontal waves 52 exercise, if these are already partially swung out of the substantially vertical rest position. The angle of rotation around which the auxiliary flaps 54 the wind flaps 50 lag, for example, is in the range of 20 to 90 ° and preferably in the range of 30 to 70 °. In the illustrated embodiment, the angle is 45 °. The auxiliary flaps 54 They are basically hemispherical, but they can also be flat.

In an advantageous development of the wind turbine can be provided that the surface of the wind flaps 50 is occupied by solar cells. These contribute to the operation of the wind turbine by the conversion of solar energy into electrical energy additional regenerative energy. It can be provided in windless or with only a small amount of wind the wind flaps 50 actively pivoting with respect to their pivoting direction so that the maximum possible yield of solar energy is obtained. It is also conceivable that at low wind speeds an optimization takes place so that the total energy, ie the sum of wind and solar energy, is maximized. Optionally, therefore, a not optimal for wind energy use position of the wind flaps 50 be taken in favor of increased solar energy conversion. In calm or very low wind speed, in which essentially only solar energy can be obtained, can also be provided to lower the rotor of the wind turbine.

As in the embodiment of 1 is a windbreak 60 provided, which surrounds the wind turbine in the lower region up to a predetermined height, for example up to a height of 2.50 m. For the sake of better representability are in the 3 three of the wind wings and the windbreak 60 only partially shown.

LIST OF REFERENCE NUMBERS

10

mast

11

vertical axis of rotation

12

vertical guide

20

hoist

21

lifting cylinder

22

lifting rod

23

crossbeam

24

rope

30

support cylinder

31

pivot bearing

32

ring generator

40

rotary cylinder

41

boom

42

vertical strut

43

wind deflector

44a-c

storage

50

wind flap

51

horizontal swivel axis

52

horizontal wave

53

lever

54

auxiliary flap

60

windshield

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• DE 2401214 A1 [0004]

Claims (15)

Wind turbine, comprising one about a vertical axis of rotation ( 11 ) rotatable rotor with at least one wind flap ( 50 ) coming from a rest position in a direction about a horizontal axis ( 51 ) is pivotable, characterized in that the rotor in the direction of the vertical axis of rotation ( 11 ) is movable. Wind turbine according to claim 1, in which the rotor is a rotary cylinder ( 40 ), which is rotatable about a support cylinder ( 30 ) is mounted, wherein the support cylinder ( 30 ) by a vertical guide ( 12 ) movable in a vertical direction on a central mast ( 10 ). Wind turbine according to claim 2, in which a lifting device ( 20 ) provided on the support cylinder ( 30 ) acts. Wind turbine according to claim 3, in which the lifting device ( 20 ) a lifting cylinder ( 21 ) and a reciprocating piston ( 22 ). Wind turbine according to claim 4, wherein the lifting cylinder ( 21 ) and the lifting rod ( 22 ) within the mast ( 10 ) are arranged. Wind turbine according to claim 4, wherein the lifting cylinder ( 21 ) the support cylinder ( 30 ) and the lifting rod ( 22 ) the masts ( 10 ). Wind turbine according to one of claims 1 to 6, in which a windbreak ( 60 ) is provided, which surrounds the rotor in a lowered vertical position wholly or partially. Wind turbine according to one of claims 1 to 7, wherein the vertical position of the rotor is adjusted depending on a measured speed of the rotor and / or a measured wind speed. Wind turbine according to one of claims 1 to 8, in which the wind flaps ( 50 ) are actively pivotable. Wind turbine according to one of claims 1 to 9, in which the wind flaps ( 50 ) are fully or partially covered with solar cells on at least one of their surfaces. Wind turbine according to one of claims 2 to 10, wherein the rotary cylinder ( 40 ) of a wind deflector ( 43 ), the wind on the wind flaps ( 50 ) steers. Wind turbine according to claim 11, wherein the wind deflector ( 43 ) in a section between two wind flaps ( 50 ) is asymmetrical. Wind turbine according to one of Claims 2 to 12, in which a ring generator ( 32 ) for generating an electric current between the support cylinder ( 30 ) and the rotary cylinder ( 40 ) is arranged. Method for operating a wind power plant with one around a vertical axis of rotation ( 11 ) rotatable rotor, characterized in that the rotor is moved depending on its measured speed in the vertical direction. The method of claim 14, wherein the rotor is moved depending on a measured wind speed in the vertical direction.

Images