GB2451472A

GB2451472A - Wind turbine control structure

Info

Publication number: GB2451472A
Application number: GB0714883A
Authority: GB
Inventors: John William Robertson
Original assignee: Individual
Current assignee: Individual
Priority date: 2007-07-31
Filing date: 2007-07-31
Publication date: 2009-02-04
Anticipated expiration: 2027-07-31
Also published as: WO2009016413A3; GB0714883D0; WO2009016413A2; GB2451472B

Abstract

A wind turbine control structure comprises a plurality of generally vertically extending panels arranged to define a chamber 11 for housing a, preferably vertical axis, wind turbine 12, at least some of the panels comprising doors 21 selectively movable between open (figure 5) and closed (figure 4) positions by being pivoted about generally vertical axes to control the flow of wind through the chamber 11. The structure also comprises a multiplicity of generally vertical deflectors 13 disposed externally of the chamber 11 and arranged so that depending upon the wind direction relative to the deflectors 13, at least some of the deflectors 13 direct wind towards the chamber 11. Each deflector 13 defines a respective aperture 26 in the region of the chamber 11, each aperture 26 being closed by an adjacent door 21 when in its open position. Two pivoting doors 21 may be provided between adjacent deflectors 13. Each deflector 13 may have a laterally extending fin 30 extending from an edge thereof. The opening and closing of the doors 21 may be controlled in accordance with wind force and direction.

Description

WIND MANAGEMENT STRUCTURE

This invention relates to wind management structure and in particular to a structure for adjusting the amount of wind flowing through a wind turbine housed in the structure.

Nuclear fission and the burning of fossil fuels are processes currently used to produce most of the world's electricity, but both of these processes are known adversely to affect the environment. In particular, the burning of fossil fuels contributes to acid rain, global warming and air pollution and nuclear fission generates radioactive waste that must be disposed of safely. Moreover, following the industrial revolution the demand for energy has continually increased and consequently the supply of fossil fuels and nuclear fuels is rapidly depleting.

In view of the problems concerning the use of fossil fuels and nuclear fuels, the use of renewable energy sources has become increasingly popular in the generation of electricity. The harnessing of wind power is believed to have quadrupled over the passed six years and wind turbines currently generate over 1% of the electricity used worldwide. Nowadays three-blade, horizontal axis wind turbines mounted on tall pylons are most common. Some of these turbines are meters high which is necessary because the blades require laminar wind flow to ensure smooth operation. Also the wind speed is significantly greater at high altitudes due to the presence of drag near the earth's surface and also the reduced viscosity of air, and so more electricity can be generated. However, these turbines have many disadvantages, including the cost of transporting and erecting such installations and the difficulty in attaining planning consent due to their unpleasant appearance, noise and the killing of endangered birds. In view of the enormity of these wind turbines it is often unfeasible for installation at locations where electricity is required and so they are installed in remote areas and the electricity is transmitted to the required areas, thereby consuming more power.

Buildings for housing wind turbines have been proposed previously and which overcome some of the problems discussed above. These buildings include an interior in which the turbine is housed and openings to enable wind to flow in and out of the interior, the openings being tapered so as to funnel the wind towards the chamber. Some buildings include shutters adapted to adjust the amount of wind flowing though the openings. However, such buildings are unsuitable for large turbines capable of generating lots of power.

It is an object of the present invention to overcome the above problems by providing a structure for housing a wind turbine and which is not unsightly, noisy nor likely to kill birds. It is a further object of the present invention to provide a structure in which a wind turbine can operate efficiently at reasonably low altitudes. It is yet a further object of the present invention to provide a structure that enables a wind turbine to operate in high winds and optimise the flow of wind towards the chamber.

According to a first aspect of the invention, there is provided a wind management structure for a wind turbine, which structure comprises: -a plurality of generally vertically extending panels arranged to define a chamber for housing the wind turbine, at least some of the panels comprising doors selectively movable between open and closed positions by being pivoted about a generally vertical axis to control the flow of wind through the chamber; and -a multiplicity of generally vertical deflectors disposed externally of the chamber and arranged so that depending upon the wind direction relative to the deflectors, at least some of the deflectors direct wind towards the chamber, each deflector defining a respective aperture in the region of the chamber, each said aperture being closed by an adjacent door when in its open position.

Preferably each deflector has an inner edge spaced from the periphery of the chamber and the aperture is defined between said inner edge and the periphery of the chamber. Most preferably each deflector is wholly separate from the chamber and the aperture is defined by a gap between the inner edge of the deflector and the periphery of the chamber.

In an alternative arrangement each deflector is conjoined to the chamber and each deflector has at least one said aperture formed therethrough, in the vicinity of the chamber.

In a preferred arrangement three generally vertical deflectors are provided, substantially equi-spaced around the chamber. Preferably two adjacent deflectors define a wind path having a cross-sectional area which reduces inwardly towards the periphery of the chamber, the path being substantially linear or arcuate. Advantageously, the reduced cross- section causes the wind flowing towards the chamber to accelerate and thereby generate more power to drive a turbine located in the chamber. The length of the deflectors may vary according to the available space and surroundings. The height of the deflectors may also vary, but the height at the inner ends should preferably be equal to the height of the doors.

Advantageously the length of the gaps between the deflectors and the periphery of the chamber is approximately equal to the width of the doors so that each door may locate in its respective gap. Alternatively the doors may be wider than the length of the gaps so that each door overlies its respective gap when in its open position. The doors are likely to be closed or in an intermediate position when high winds are prevalent which would otherwise cause increased levels of noise and possibly damage a wind turbine located in the chamber. Under these circumstances at least some of the wind bypasses the chamber by flowing through the gaps between the deflectors and the periphery of the chamber.

Preferably, two casement type doors are provided between two deflectors and the pivoting axis of each door is generally vertical and located on the periphery of the chamber. Most preferably the two doors are configured to form a set of double doors so that their free vertical edges remote from the pivoting axes meet on the periphery of the chamber when the doors are in their closed position.

Alternatively, one door may be provided between two deflectors, the pivoting axis of the door being located on the periphery of the chamber near one of the deflectors and the free end of the door being located near the other of the two deflectors when said door is in its closed position.

In one arrangement the pivoting axis of each door may be located on a line extending between the inner end of the deflector and the centre of the chamber. In an alternative arrangement, the pivoting axis may be located in spaced relation from a line extending between the inner end of the deflector and the centre of the chamber.

Advantageously, there may be provided a support structure having a plurality of interconnected pillars to which the doors are pivoted by hinges or the like. The support structure may include an upper frame member that connects to the upper ends of each pillar to provide rigidity. The upper frame member may be any polygonal shape, but most preferably it is triangular or hexagonal.

Optionally, fins may be provided on the upper frame member and arranged to extend outwardly and upwardly therefrom to direct wind towards the chamber.

Each deflector has an upper surface which may be provided with a pair of fins extending laterally therefrom in opposed directions so as to overhang the paths defined on both sides of the deflector. The fins serve to direct some of the wind travelling along the deflectors downwardly.

Preferably, a ground engaging wheel is mounted on each door, the wheel having an axis of rotation extending generally radially to the pivoting axis of the door. For installations having large, heavy doors it may be preferable to have more than one wheel. Guide means, such as grooves or the like, could be provided externally of the chamber and along which the wheels would roll to ensure uninhibited operation of the doors.

Advantageously, actuation means are provided to adjust the position of the doors according to wind force and wind direction, and most preferably the actuation means includes a hydraulic ram. Each door would most preferably be operable independently of the other doors and so each door may include its own hydraulic ram. Alternatively, the actuation means may include a geared system having a manual and or automatic drive system.

There may also be provided sensing means for wind force and wind direction and a processor for processing the output of the sensing means and providing an output signal for one or more door actuation means. Most preferably the sensing means would be located on the wind management structure but it may instead be located at a remote location provided the weather at that location is representative of the weather at the wind management structure.

According to a second aspect of the invention there is provided a combination of a wind management structure as claimed in any of the preceding claims, and a wind turbine provided in the chamber. Preferably, the wind turbine comprises: -a vertically disposed central shaft; -a plurality of arms extending radially from the central shaft; and -a plurality of vanes, one provided on the radially outer end of each arm.

In one embodiment, the arms are arranged in several discrete, axially disposed planes, and in an alternative embodiment the arms are arranged in a spiral formation around the shaft.

In some circumstances a multiplicity of wind turbines may be provided in the chamber.

Most preferably, the vanes comprise cups having an open end and a closed end, the cups being arranged so that the closed end of one cup faces the open end of an adjacent cup connected to an arm lying substantially in the same axial plane.

By way of example only, one embodiment of the present invention will now be described in detail, reference being made to the accompanying drawings, in which: Figure 1 is a perspective view of the invention which includes three deflecting walls spaced around the periphery of a structure for housing a turbine; Figure 2 is a plan view of the invention shown in Figure 1, in which doors provided on the structure are arranged in their closed position; Figure 3 is a plan view corresponding to that shown in Figure 2, but with the doors arranged in their open position; Figure 4 is a perspective view of the invention in which fins are provided on the deflecting walls and the doors are arranged in their closed position; Figure 5 is a perspective view corresponding to that shown in Figure 4, but with the doors of the structure arranged in their open position; Figure 6 is a plan view of the invention in which fins are provided on the structure in which the turbine is housed; and Figure 7 is a front view of the arrangement shown in Figure 6.

Referring to Figures 1 to 3 there is shown a wind management structure comprising a main structure generally indicated 10 defining a chamber 11 in which a wind turbine 12 is housed and three deflecting walls 13 equally spaced around the periphery of the chamber. The main structure 10 is located on a substantially flat, horizontal concrete base (not shown) and includes an upper frame 14 supported by three pillars 15. The upper frame 14 is triangular and comprises three struts 1 6 of equal length which are interconnected to define three corners. Each pillar 15 has a lower end 17 secured to steel fixings (not shown) mounted in the concrete base and an upper end 18 secured to a corner of the upper frame by bolts or like fastenings (not shown) to provide rigidity.

The main structure 10 includes three openings 20 through which wind may enter and leave the chamber, each opening being defined by two pillars 15, the base and the upper frame 14. Each opening is provided with two doors 21 movable between open and closed positions, so as to control the flow of wind through the chamber 11, the two doors being hinged to the two pillars respectively, and arranged to pivot about a generally vertical axis. Each door 21 has a first vertical side 22 which extends alongside the pillar 15 to which said door is hinged and a second vertical side 23 which locates midway along the opening 20 when said door is in its closed position and co-operates with the second vertical side 23 of the other of the two doors 21. Each door is also supported by a ground engaging wheel provided adjacent the second vertical side 23. Each wheel has an axis of rotation extending generally perpendicular to the pivoting axis of the door on which the wheel is provided.

The three deflecting walls 13 are equally spaced around the chamber 11 and aligned with the three pillars 15 respectively, each deflecting wall having a long axis that extends through its respective pillar 15 and the central axis of the chamber 11. Thus, two adjacent deflecting walls 13 define a path 25 which tapers inwardly towards the chamber 11. The deflecting waIls 13 are spaced from the periphery of the chamber 11 to define gaps in which the doors 21 locate when in their open position, as shown in Figure 3.

Actuation means (not shown), such as a hydraulic ram driven by a hydraulic pump is provided on the main structure 10 and is operable to move the doors 21 between their open and closed positions. The main structure 10 also includes an anemometer (not shown) to detect wind speed and wind direction which sends a signal to a computer (not shown) for controlling the actuation io means.

Under normal wind conditions the doors 21 are configured in their open position whereat they locate in the gaps 26 defined by the pillars 15 and the deflecting waIls 13, each door 21 lying substantially in the same plane as its respective deflecting wall 13 to provide a continuous surface extending radially from the periphery of the chamber 11. Thus, as the wind flows along the path 25, it is funnelled towards the chamber 11 by the deflecting walls 13 and doors 21, thereby causing it to accelerate. Under high wind conditions it is preferable to reduce the amount of wind entering the chamber 11 to prevent damage and the generation of too much noise. Thus, the doors 21 can be moved to an intermediate position whereat some of the wind travelling along the path 25 enters the chamber 11 and some of the wind passes through the gaps 26. Under severe weather conditions the doors 21 should be moved to their closed position whereat no wind is able to enter the chamber 11 to drive the turbine 12.

In an alternative arrangement shown in Figures 4 and 5, a fin 30 is provided on the upper surface 31 of each deflecting wall 13, each fin 30 comprising two limbs 32 extending laterally in opposed directions so as to overhang the paths 25 on either side of said deflecting wall 1 3. Wind flowing alongside the deflecting walls 13 strikes the underside 33 of the limbs 32 and is thus inhibited from rising above the deflecting walls 13 and bypassing the chamber 11.

Figures 6 and 7 show yet a further arrangement in which three equl-spaced roof fins 40 are mounted on the upper frame 14 and extend radially outwardly from the centre thereof. Each roof fin 40 has an outer end 41 that connects to the inner end 35 of a deflecting wall fin 30 and an inner end 42 disposed at the centre of the upper frame 14 and connects with the inner ends 42 of adjacent roof fins 40 to form a roof generally indicated 43. Each roof fin 40 comprises two limbs 44 arranged at an angle to each other to define a V-shape cross section corresponding to that of the deflecting wall fins 30. The roof fins 40 and the deflecting wall fins 30 slope downwardly from the centre of the upper frame 14 to enable rain water to drain away.

Claims

1. A wind management structure for a wind turbine, which structure comprises: -a plurality of generally vertically extending panels arranged to define a chamber for housing the wind turbine, at least some of the panels comprising doors selectively movable between open and closed positions by being pivoted about a generally vertical axis to control the flow of wind through the chamber; and -a multiplicity of generally vertical deflectors disposed externally of the chamber and arranged so that depending upon the wind direction relative to the deflectors, at least some of the deflectors direct wind towards the chamber, each deflector defining a respective aperture in the region of the chamber, each said aperture being closed by an adjacent door when in its open position.

2. A wind management structure as claimed in claim 1, wherein each deflector has an inner edge spaced from the periphery of the chamber and the aperture is defined between said inner edge and the periphery of the chamber.

3. A wind management structure as claimed in claim 2, wherein each deflector is wholly separate from the chamber, the aperture being defined by a gap between the inner edge of the deflector and the periphery of the chamber.

4. A wind management structure as claimed in claim 1, wherein each deflector is conjoined to the chamber, each deflector having at least one said aperture formed therethrough, in the vicinity of the chamber.

5. A wind management structure as claimed in any of the preceding claims, wherein three generally vertical deflectors are substantially equi-spaced around the chamber.

6. A wind management structure as claimed in any of the preceding claims, wherein two adjacent deflectors define a wind path, the cross-sectional area of which reduces inwardly towards the periphery of the chamber.

7. A wind management structure as claimed in any of the preceding claims, wherein two pivoting doors are provided between two adjacent deflectors.

8. A wind management structure as claimed in any of the preceding claims, wherein the chamber includes a support structure having a plurality of interconnected pillars, the doors being pivoted to the pillars.

9. A wind management structure as claimed in any of the preceding claims, wherein each deflector has an upper surface on which there is provided a fin extending laterally therefrom.

10. A wind management structure as claimed in any of the preceding claims, wherein a ground engaging wheel is mounted on each door, the wheel having an axis of rotation extending generally radially to the pivoting axis of the door.

11. A wind management structure as claimed in any of the preceding claims, wherein actuation means are provided to adjust the position of the doors according to wind force and wind direction.

12. A wind management structure as claimed in claim 11, wherein the actuation means includes a hydraulic ram.

13. A wind management structure as claimed in claim 11 or claim 12, wherein there is provided sensing means for wind force and wind direction and a processor for processing the output of the sensing means and providing an output signal for controlling the actuation means.

14. The combination of a wind management structure as claimed in any of the preceding claims, and a wind turbine provided in the chamber.

15. The combination of claim 14, wherein the wind turbine comprises: -a vertically disposed central shaft; -a plurality of arms extending radially from the central shaft; and -a plurality of vanes, one provided on the radially outer end of each arm.

16. A combination as claimed in claim 15, wherein the vanes comprise cups having an open end and a closed end, the cups being arranged so that the closed end of one cup faces the open end of an adjacent cup connected to an arm lying substantially in the same axial plane.

17. A wind management system as claimed in any of the preceding claims and substantially as hereinbefore described, with references to and as illustrated in the accompanying drawings.