WO2008131719A2

WO2008131719A2 - Suspended wind power plant comprising a wind concentrator

Info

Publication number: WO2008131719A2
Application number: PCT/DE2008/000640
Authority: WO
Inventors: Harald Eilers
Original assignee: Harald Eilers
Priority date: 2007-04-30
Filing date: 2008-04-15
Publication date: 2008-11-06
Also published as: WO2008131719A3; DE102007020632A1

Abstract

The invention relates to a wind power plant (10) having a ground station (12) and a flying body (14) connected to the ground station (12), said flying body comprising at least one rotor (16; 52) and a generator (18) connected to the rotor (16; 52). According to the invention, a wind concentrator (34; 40; 44; 48) is provided that interacts with the rotor (16).

Description

Wind turbine

The invention relates to a wind power plant having a ground station and a missile connected to the ground station, which has at least one rotor and a generator connected to the rotor. According to a second aspect, the invention relates to a method for operating a wind turbine.

In order to dispense with a wind turbine on a tower, it is known to connect a ground station, for example via a wire with a missile on which a rotor for generating electrical power is mounted. For example, a wind energy plant of the company Menn is known, which has a helium-filled balloon, on the circumference of which turbine blade-like protuberances are provided. The balloon is lighter than air due to its helium filling and is allowed to rise on a rope. Due to the wind, the balloon starts to spin, which is why a generator connected to the rope and the balloon generates electricity. The electricity is conducted to the ground via a cable connected to the cable.

A disadvantage of this wind turbine is that it has a comparatively low speed, so that only a low efficiency is achievable. It is therefore only in rare cases with such a system economically generate electricity.

The invention has for its object to overcome disadvantages in the prior art. The invention solves the problem by a generic wind turbine, which has a cooperating with the rotor wind concentrator.

An advantage of the invention is that due to the wind concentrator, a comparatively small rotor diameter can be selected, which achieves a high speed. For this reason, advantageously, a comparatively small generator can be used. A small rotor also makes lower demands on the materials to be used, since only a smaller weight must be collected.

It is also advantageous that the wind power plant according to the invention can easily be operated at high altitudes, for example beyond the Prandtl or the Ekman layer. Beyond these layers, the atmosphere has less turbulence, so that mechanical peak loads of wind turbines are avoided. This increases the life of the wind turbine. It is also advantageous that the wind concentrator can be realized with simple means. Movable components are expendable, so that the wind concentrator wears little and is easy to manufacture. The wind concentrator also means that the wind turbine starts up even at low wind speeds, which means that only minimal downtimes occur.

In the context of the present description, a ground station is understood in particular to mean any component of the wind power plant which is designed to fix the missile relative to the earth. The ground station can be, for example, a foundation or a sufficiently heavy dimensioned ground-based mass piece. For a high seas application, the ground station may also include a pontoon secured to the sea floor via an anchoring device or a weight. It is possible, but not necessary, for the ground station to be immovable. The bottom station can also be formed, for example, by a ship to which the missile is attached. In this way, the wind turbine can be used to generate power for ships and possibly act as a sail.

A missile is understood in particular to mean a component of the wind power plant which can float in the air without supplying external energy.

A rotor is understood in particular to mean any device which converts an air flow into a rotary motion. Rotors are, for example, a propeller, a tangential rotor, a cross-flow rotor, a Darrieus rotor, a Savonius rotor or other designs. The rotor may, but not necessarily, be single-stage, that is to say all moving parts rotate in the same direction. It is alternatively also possible that the rotor is constructed in multiple stages. For example, the rotor may be constructed in two stages and comprise two stages of propellers which rotate in opposite directions. In this way, torques can be absorbed in a simple manner.

A wind concentrator is understood in particular to mean a device with which wind is concentrated on the rotor. A wind concentrator is designed to increase the wind speed on the rotor.

In a preferred embodiment, the missile is designed to float in the air. In particular, the missile has a support body which is lighter than air and which is designed to act as a wind concentrator. The advantage of this is that the support body performs two functions, namely the one hand to keep the missile without supplying external energy at an altitude above the ground, and on the other hand, to act as a wind concentrator, so that a particularly small and thus lighter rotor can be used can. At the same time, this dual function allows a particularly simple and elegant construction that is easy to manufacture and transport. In a preferred embodiment, the rotor is rotatably mounted about a rotor axis of rotation, wherein the support body has a streamlined, preferably a rotational elliptical, a longitudinal axis Tragkörperlängsachse central body, wherein the support body longitudinal axis of the rotor rotational axis corresponds and wherein the rotor blades extend transversely to the axis of rotation about the central body. For example, the rotor blades protrude perpendicular to the rotor axis of rotation beyond the central body. In this way, air, which flows in the vicinity of the support longitudinal axis to the central body to, passed around the central body around the rotor blades. The central body then acts as a wind concentrator

Particularly preferably, the support body has a rotor shell, which is arranged radially outside the rotor and forms an impeller with the rotor. In this way, a disco effect is avoided in which the sunlight is shaded and illuminated in rapid succession on the earth's surface, which is very disturbing for persons staying in the area. Advantageously, the efficiency of the rotor is also increased.

To be able to switch off the wind turbine with excessively strong wind, rotor blades of the rotor, in particular all rotor blades, can be brought to a slipstream of the central body by moving on the rotor axis of rotation. In this position, they are no longer directed by the wind, so that no more torque is applied to the generator and it can be easily shut down.

Preferably, the support body has a toroidal outer body, which is arranged radially outside the rotor, so that a rotor blade path of the rotor blades extends between the outer body and the central body. A toroidal outer body is to be understood as meaning a body whose cross-section has a convex closed curve and which extends in an annular manner around the longitudinal axis of the support body. For example, the outer body has an elliptical or teardrop-shaped cross section. In the case of a circular cross-section results an outer body in the form of a torus. The toms is thus a special case of the to- oid outer body in the sense of this description.

An advantage of such a designed toroidal outer body is its simple geometric shape, so that it is very easy to manufacture. Due to its shape, the toroidal outer body is also self-stabilizing. It is therefore possible, but not necessary, for the toroidal outer body to have an inner framework. In particular, the outer body may be formed semi-rigid or as an impact body stabilized essentially only by an internal pressure of carrier gas present in the outer body.

According to an alternative embodiment, the support body has two prismatic outer bodies which extend along parallel outer body longitudinal axes and are arranged with their outer body longitudinal axes next to one another so that between them a flow channel is formed, wherein at least two rotatable about respective rotor longitudinal axes Savonius rotors are provided and wherein the rotor longitudinal axes extend parallel to the outer body longitudinal axes and between the outer body longitudinal axes.

The Savonius rotors are preferably arranged such that they rotate partly in the flow passage and partly in a slipstream of the outer bodies. In this way, a particularly high efficiency of the Savonius rotor is achieved, since the part of the Savonius rotor, which moves against the wind direction, runs in the lee.

It is preferred that the central body and / or the outer body include or include a carrier gas, in particular hydrogen or helium. The advantage of hydrogen in addition to its availability is its particularly low density, so that a particularly large buoyancy is achieved. Due to the altitude of the missile, the hydrogen also poses no significant security risk. Helium benefits from its non-flammability. It is possible that the support body contains both helium and hydrogen, for example in redundant, separate chambers.

The missile preferably comprises an electrolysis device for electrolyzing water. In this way, carrier gas can be replenished in the form of hydrogen, which inevitably diffuses through an outer shell of the support body to the outside.

Preferably, the missile is connected by means of a flexible connecting element with the ground station, such as a cable made of highly tear-resistant plastic. Suitable examples are high-strength polyethylene fibers such as Dyneema®.

For deriving electrical power generated by the generator, an electrical cable is preferably provided which is connected to the connecting element. For subsequent delivery of water to the electrolysis device, for example, a water hose is connected to the connecting element. In order to be able to pump water in the water hose over great heights without the water hose having to have a high compressive strength, according to a preferred embodiment, at least one water pump is provided for pumping the water, which is fastened to the connecting element. The water pump is electrically driven, for example. Alternatively, the water pump comprises a fuel cell for converting hydrogen generated in the missile into electricity, wherein the hydrogen is connected via a gas hose, which is also attached to the connecting element. It is also possible that a gas hose is provided to direct either hydrogen as a carrier gas to the missile or to hydrogen in the missile electrolyzed hydrogen to the ground station.

According to one embodiment, the central body and / or the outer body have a framework which surrounds carrier gas cells. In other words, the central body and / or the outer body are designed as rigid airships. alternative the central body and / or the outer body may be formed as semi-rigid airships, in particular as Kielluftschiffe. According to a further alternative, the central body and / or the outer body are filled directly with the carrier gas. In this case, they are designed as impact airships.

The method according to the invention preferably comprises the step of detecting an altitude of the missile, a comparison of the altitude with a target altitude and the electrolyzing of water, so that hydrogen is produced and pumped as passing the hydrogen into the carrier body. Conveniently, the electrolysis of the water is carried out in the missile itself.

Embodiments of the invention will be explained in more detail below with reference to the accompanying drawings. Showing:

FIG. 1 a shows a wind turbine according to the invention in a longitudinal section,

FIG. 1b shows the wind power plant according to FIG. 1a in a cross section,

Figure 2a is a schematic view of a position of rotor blades at

Normal operation,

Figure 2b shows another position of rotor blades for switching off the

Wind Turbine

3a shows a second embodiment of a wind turbine according to the invention in a longitudinal section,

FIG. 3b shows the wind power plant according to FIG. 3a in a cross section,

FIG. 4 shows a further embodiment of a wind power installation according to the invention, in which the outer body has a drop-shaped cross-section,

Figure 5a shows a further embodiment of an inventive

Wind turbine in a longitudinal section,

FIG. 5b shows a cross section through the wind power plant according to FIG. 5a,

FIG. 6 a shows a longitudinal section through a further embodiment of a wind power plant according to the invention,

FIG. 6b shows a cross section of the wind power plant according to FIG. 6a, 7a shows an embodiment for rotors for the wind power plant according to FIGS. 6a and 6b, FIG.

FIG. 7b shows a position for the rotors according to FIG. 7a for switching off the wind power plant,

FIG. 7c shows another position for the rotors according to FIG. 7a for switching off the wind power plant,

FIG. 8 a shows a schematic representation of an energy transfer from the missile to the ground station,

8b shows an alternative embodiment for an energy transfer of

Missile to ground station,

FIG. 8c shows a further alternative embodiment for transmitting energy from the missile to the ground station,

FIG. 8d shows a further alternative embodiment for an energy transmission of missile to the ground station,

FIG. 9 a shows a first possibility for regulating a buoyancy of the missile,

Figure 9b another way to regulate the buoyancy of the missile and

FIG. 10 shows a schematic system overview for the embodiment according to FIG

FIG. 8b. FIG. 1 shows a wind turbine 10 with a ground station 12 and a missile 14 connected to the ground station 12, which has a rotor in the form of a propeller 16 and a generator 18 connected to the propeller 16. The ground station 12 is connected to a longitudinal member 22 of the missile 14 via a connecting element in the form of a retaining cable 20. The longitudinal member 22 extends along a longitudinal axis L of the missile 14.

The propeller 16 has four rotor blades 24.1, 24.2, 24.3 and 24.4, of which the rotor blades 24.1 and 24.3 are visible in FIG. 1a. In the following, reference signs without counting suffix designate the respective object as such. The rotor blades 24 are fastened to an arm 26, which is rotatably mounted in a hub 28 about the longitudinal member 22. On the arm 26, a ring gear 30 is rigidly fixed, which meshes with a gear 32 of the generator 18.

In the following reference numerals without Zählsuffix denote the corresponding object as such. The rotor blades 24 project beyond a central body 34 of the missile 14, so that they can be flowed by wind, which is indicated by arrows W, which is deflected from the central body 34.

The central body 34 has a scaffold, not shown in FIG. 1a, with which the longitudinal member 22 is held and which is surrounded by a substantially gas-tight envelope 36. The central body 34 therefore has the structure of a Kielluftschiffs.

The central body 34 has an outer shape of an ellipsoid of revolution whose cross section is an ellipse. In this way, the wind W becomes effective around the

Center body 34 passes around and meets there on the rotor blades 24, which rotate about a rotor axis of rotation R, which corresponds to the longitudinal axis L. The central body 34 comprises schematically drawn carrier gas cells 38.1, 38.2, 38.3, 38.4 which are equipped with a gas which is lighter than air, for example with hydrogen are filled, so that the missile 14 is lighter than the surrounding air and thus floats in the air.

The missile 14 also has a rotor shell 40, which is arranged radially outside of the propeller 16 and concentric therewith, so that the rotor shell 40 and the propeller 16 form an impeller. Alternatively, the propeller 16 has at its radially outer ends T-shaped folds, which lead to the same effect.

FIG. 1b shows the wind power plant 10 according to FIG. 1a in a cross section. It can be seen that the rotor casing 40 is fastened to the central body 34 via four webs 42.1, 42.2, 42.3, 42.4.

FIG. 2 a shows a detailed view of the central body 34 and of the rotor blade 24. 1, which, like all other rotor blades, is arranged so as to be radially displaceable on the arm 26. In the position shown in FIG. 2a, the rotor blade 24.1 can be flowed against by the wind W and drives the generator not shown in FIG. 2a. In the position shown in FIG. 2b, the rotor blade 24.1 has been moved radially toward the longitudinal axis L, so that the wind W no longer encounters an attack surface and the propeller 16 stands still. In this way, the wind turbine can be easily switched off when the wind is too strong. Alternatively, a pitch system is provided in which the rotor blades 24 are rotated about their longitudinal axis out of the wind.

FIG. 3 a shows an alternative embodiment of a wind power plant 10 according to the invention, in which the missile 14 does not comprise any central bodies but instead has a toroidal outer body 44. The toroidal outer body 44 has an elliptical and therefore convex cross-section and is rotationally symmetrical to the longitudinal axis L. It surrounds the propeller 16 by forming a narrow radial air gap 46 and acts like the central body 34 in Figures 1a and 1b as a wind concentrator for the propeller 16th The toroidal outer body 44 is constructed according to the principle of an impact airship and connected via webs not shown in Figure 3a with the side member 22. By filling with a gas or gas mixture which is lighter than air and which in particular comprises helium, hydrogen or a mixture of both, the outer body 44 is lighter than air, so that the missile 14 floats. FIG. 3b shows a cross section through the wind power plant according to FIG. 3a.

Figure 4 shows an alternative embodiment of a wind turbine 10 according to the invention, in which the toroidal outer body 44 has a teardrop-shaped cross-section. A thus shaped outer body 44 has a particularly low air resistance and causes a shell turbine effect, which additionally enhances the effect as a wind concentrator.

FIGS. 5a and 5b show a further embodiment of a wind power plant 10 according to the invention, which is designed as a hybrid of the embodiments according to FIGS. 1a and 1b on the one hand and the embodiments according to FIGS. 3a and 3b on the other hand.

FIG. 6a shows a further embodiment of a wind power installation 10 according to the invention, which has a first prismatic outer body 48.1 and a second prismatic outer body 48.2, both of which extend along parallel outer body longitudinal axes A1 and A2 and which are both constructed according to the principle of a Kielluft ship. The prismatic outer bodies 48.1, 48.2 are filled with a carrier gas, so that the missile 14 floats. Between the prismatic outer bodies 48.1, 48.2, a flow channel 50 is formed, in which two Savonius rotors 52.1, 52.2 protrude, which are rotatably mounted about respective rotor longitudinal axes R1 and R2.

FIG. 6b shows a cross section through the wind power plant 10 according to FIG. 6a. It can be seen that the Savonius rotors 52.1, 52.2 are connected to one another in a rotationally rigid manner via left-side toothed wheels 54.1a and 54.2a or right-hand toothed wheels 54.1b and 54.2b. Via further gears 54.3a or 54.3b ste- hen the Savonius rotors 52.1, 52.2 in operation also in torsionally rigid connection with generators 56.1, 56.2.

Figure 7a shows schematically the two Savonius rotors 52.1, 52.2 in normal operation, i.e. during the generation of electricity. It is possible that the respective blades 58.1, 58.2 move on circular paths which overlap one another. Since the Savonius rotors 52.1, 52.2 are coupled torsionally rigid with each other, a collision of the blades 58.1 and 58.2 is not possible.

Figure 7b shows a rest position of the two Savonius rotors 52.1, 52.2, in which they are driven to stop the wind turbine.

FIG. 7c shows another possibility for immobilizing the wind turbine 10. For this purpose, the Savonius rotors 52.1, 52.2 are moved into a lee of the prismatic outer bodies 48.1 and 48.2, so that they can no longer be flown by the wind.

FIG. 8 a shows a schematic representation of lines leading from the ground station 12 to the missile 14. To weight the missile 14 may have a ballast tank 60 which is connected via a water hose 62 to the ground station 12. The weighting serves to control the flying height of the missile 14. The carrying gas cells 38 can be connected via a gas hose 64 to a carrier gas supply in the ground station 12. The generator 56 is connected to the ground station 12 via a power cable 66 for transmission of the generated power. The water hose 62, the gas hose 64 and the power cable 66 are connected to the not shown in Figure 8a tether 20, which receives their weight. In the ground station 12, an electrical control is provided which is adapted to detect the flying height of the missile 14 and to supply the missile 14 with load through the water hose 62 when the flying height is to be reduced. Figure 8b shows an alternative embodiment in which the water hose 62 carries water into the ballast tank 60, which in turn communicates with an electrolyzer 68. The electrolyzer 68 draws power from the generator 56 and thus generates hydrogen 70 which is supplied to the carrier gas cells 38. In this way, by electrolyzing water, the amount of carrier gas in the support body can be changed so that there is always enough carrier gas to keep the missile 14 in suspension. There is a correspondingly established control, as in the embodiment described in FIG. 8a.

FIG. 8 c illustrates a further alternative embodiment, in which the carrier gas cells 38 are supplied with carrier gas from the ground station 12 via the gas hose 64. The control of the altitude of the missile 14 is effected by controlling the gas volume in the missile 14. For this purpose, a correspondingly configured electrical control is provided in the ground station, which increases the gas volume of carrier gas when the missile 14 is to gain in height.

FIG. 8 d is an illustration of a further embodiment in which diffusion losses of carrier gas by carrier gas from the gas tube 64 are compensated. The height control of the missile 14 is done as in the embodiments of Figures 8a and 8b by supplying and discharging ballast from the ballast tank 60th

FIG. 9a shows a further possibility for regulating the buoyancy of the missile 14. In a compressed gas storage 72, carrier gas is present, which can be introduced into the carrier gas cell 38 as required. If the buoyancy is too strong, carrier gas can be discharged from the carrier gas cell 38 through an outlet 74.

It is also possible, via the water hose 62 water in the ballast tank

60 to pump and drain from there again.

FIG. 9b shows the possibility of the carrier gas cell 38 directly via the gas hose

64 to connect to the ground station 12. FIG. 10 shows a synopsis of the above, wherein additionally pumps 76, 78, an uninterruptible power supply 82.1, 82.2, a hydrogen storage 84, a water storage 86 and crash warning lights 88 are shown.

According to an embodiment of the invention, not shown, the missile 14 has in operating position horizontally extending wings. These wings are pivotable about a horizontal axis and are designed to provide additional lift or downforce. Thus, the electrical control can be arranged to control the wings so that a predetermined altitude is maintained. This prevents the wind from pushing the missile to the ground.

The missile may also include landing skids arranged to support the missile on the ground.

Claims

claims

1. Wind turbine (10) with

(a) a ground station (12) and (b) a missile (14) connected to the ground station (12) having at least one rotor (16; 52) and a generator (18) connected to the rotor (16; 52) characterized by (c) a wind concentrator cooperating with the rotor (16)

(34; 40; 44; 48).

2. Wind power plant (10) according to claim 1, characterized in that the missile (14) is designed to float in the air.

3. Wind power plant (10) according to one of the preceding claims, characterized in that the missile (14) has a support body (34; 44; 48) which is designed to be lighter than air and as a wind concentrator.

4. Wind turbine (10) according to claim 3, characterized in that the rotor (16) about a rotor axis of rotation (R) is rotatably mounted, the support body a, in particular substantially rotationally elliptical, a supporting body longitudinal axis (L) having central body ( 34), wherein the support longitudinal axis (L) of the rotor axis of rotation (R) corresponds, and the rotor blades (24.1, 24.2, 24.3, 24.4) transversely to the rotor axis of rotation (R) on the central body (34) protrude.

5. Wind turbine (10) according to claim 4, characterized in that the supporting body has a rotor shell (40) which is arranged radially outside of the rotor (16) and forms an impeller with the rotor (16).

6. Wind turbine (10) according to one of claims 4 or 5, characterized in that rotor blades (24.1, 24.2, 24.3, 24.4) of the rotor (16) by moving on the rotor axis of rotation (R) in a lee of the central body (34 ) are brought.

7. Wind turbine (10) according to one of the preceding claims, characterized in that the support body has a toroidal outer body (44) which is arranged radially outside of the rotor (16), so that a rotor blade track of the rotor blades (24.1, 24.2, 24.3, 24.4) between the

Outer body (44) and the central body (34) extends.

8. Wind turbine (10) according to claim 7, characterized in that the outer body (44) has a C _w value of less than 0.25 and in particular has an elliptical or teardrop-shaped cross-section.

9. wind turbine (10) according to one of claims 1 to 3, characterized in that the support body comprises two prismatic outer body (48.1, 48.2), which along parallel outer body longitudinal axes (A1,

A2) and with their outer body longitudinal axes (A1, A2) are arranged side by side so that a flow channel (50) between the two outer bodies (48.1, 48.2) is formed, and that at least two rotatable about respective rotor longitudinal axes (R1, R2) Savonius -Rotoren (52.1, 52.2) are provided, wherein the rotor longitudinal axes (R1, R2) parallel to the outer body longitudinal axes (A1, A2) and between the outer body longitudinal axes (A1, A2).

10. Wind turbine (10) according to claim 9, characterized in that the Savonius rotors (52.1, 52.2) are arranged so that they partially rotate in the flow channel (50) and partially in a slipstream of the outer body (48.1, 48.2).

11. Wind power plant (10) according to one of the preceding claims, characterized in that the central body (34) and / or the outer body

(44; 48.1, 48.2) contain or contain a carrier gas, in particular a hydrogen.

12. Wind power plant (10) according to one of the preceding claims, characterized in that the missile (14) is an electrolysis device

(68) for electrolyzing water.

13. Wind turbine (10) according to one of the preceding claims, characterized in that the missile (14) by means of a flexible connecting element (20) with the ground station (12) is connected.

14. Wind turbine (10) according to claim 13, characterized in that the connecting element (20) comprises an electrical cable (66).

15. Wind turbine (10) according to claim 13 or 14, characterized in that the connecting element comprises a water hose (62) for transporting water to the missile (14).

16. Wind power plant (10) according to claim 15, characterized in that the connecting element (62) comprises at least one water pump for pumping the water, wherein the water pump comprises in particular a fuel cell.

17. Wind power plant (10) according to any one of claims 13 to 16, characterized in that the connecting element (62) has a gas hose

(64) for directing hydrogen to the water pump and / or to the ground station (12) or to a hydrogen pump.

18. Wind turbine (10) according to one of the preceding claims, characterized in that the central body (34) and / or the outer body (44; 48.1, 48.2) have or have a framework, the carrier gas cells (38.1, 38.2, 38.3, 38.4 ) surrounds.

19. Wind turbine (10) according to one of claims 1 to 17, characterized in that the central body (34) and / or the outer body (44; 48.1, 48.2) are constructed as a semi-rigid airship, in particular as a Kielluftschiff.

20. Wind power plant (10) according to one of claims 1 to 17, characterized in that the central body (34) and / or the outer body (44; 48.1, 48.2) are filled with the carrier gas.

21. Wind power plant (10) according to one of the preceding claims, characterized by an electrical control which is set up for carrying out a method according to one of claims 23 or 24.

22. A method of operating a wind turbine (10) according to any one of the preceding claims, comprising the steps of:

(a) providing a wind turbine (10) according to one of the preceding claims,

(b) filling the missile (14) with a carrier gas so that it floats and

(c) rotating the rotor (16) and generating an electrical current with the generator (18).

23. The method according to claim 22, characterized by the steps: (a) detecting an altitude of the missile (14),

(b) comparing the altitude with a target altitude, (C) when the target altitude is exceeded, providing carrier gas from a reservoir and / or electrolyzing water so that hydrogen is formed, and passing the hydrogen into a supporting body of the missile (14) and / or discharging a liquid ballast, in particular Water, from an im

Missile (14) arranged ballast tank (60).

24. The method according to claim 23, characterized by the steps:

(a) detecting an altitude of the missile (14), (b) comparing the altitude with a target altitude

(C) when the target altitude is exceeded, discharging carrier gas from the support body and / or filling a in the missile (14) arranged ballast tank (60) with liquid ballast, in particular with water.