Classifications

• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
  • F03D—WIND MOTORS
  • F03D7/00—Controlling wind motors 
  • F03D7/02—Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor
  • F03D7/0256—Stall control
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F03—MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
  • F03D—WIND MOTORS
  • F03D7/00—Controlling wind motors 
  • F03D7/02—Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor
  • F03D7/022—Adjusting aerodynamic properties of the blades
  • F03D7/0236—Adjusting aerodynamic properties of the blades by changing the active surface of the wind engaging parts, e.g. reefing or furling
• • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
  • F05—INDEXING SCHEMES RELATING TO ENGINES OR PUMPS IN VARIOUS SUBCLASSES OF CLASSES F01-F04
  • F05B—INDEXING SCHEME RELATING TO WIND, SPRING, WEIGHT, INERTIA OR LIKE MOTORS, TO MACHINES OR ENGINES FOR LIQUIDS COVERED BY SUBCLASSES F03B, F03D AND F03G
  • F05B2270/00—Control
  • F05B2270/30—Control parameters, e.g. input parameters
  • F05B2270/325—Air temperature
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
  • Y02E10/00—Energy generation through renewable energy sources
  • Y02E10/70—Wind energy
  • Y02E10/72—Wind turbines with rotation axis in wind direction

Definitions

• Windmill wing for such a mill, and add-on element to be mounted on a mill wing.
• the present invention relates to a common type windmill, i.e. with a wing-carrying rotor, the wings of which are rotated by means of an existing wind ac ⁇ tuation.
• a distinction is made differen ⁇ tiating between mills with fixed and turnably adjustable wings, respectively, and the invention relates in par ⁇ ticular to rotors with fixed wings.
• maximum effect is meant the greatest possible exploitation of the existing wind at low wind velocity up to the point where the effect gained is commensurate with the maximum effect the mill is design ⁇ ed to produce.
• the wings are automatically turned about their longitudinal axis such that their efficiency is reduced in order to safeguard the mill against overload.
• the wing rotor When the wing rotor is coupled to an AC generator the rotor speed will be reasonably constant in a large part of the wind velocity area.
• the wings move in a direction directly transversely to the wind direction and, in consequence, the inclination angle of the ensu ⁇ ing air flow on the wings depends on the wind force.
• the wings in question are stall-regulated, viz. they are profiled such that, in the said strong wind velocity area, they display increased stalling the stronger the wind is, thusly avoiding the said overload condition.
• a mill wing adjustment is chosen corresponding to high temperature operation for fully effective wings, whilst, by means of temperature sensors and coupled actuator means, a re ⁇ duction of the wing efficiency at decreasing temperature is undertaken.
• This reduction may be induced in dif ⁇ ferent ways, e.g. through an operative local deformation of sections of the wings; through controlled alteration of the angle position of the wings; or through controll ⁇ ed alteration of the effective wing surface area.
• the mill in hot weather may operate at an increased stall-wind velocity, i.e. hot, forceful winds may be exploited better without risking overload if or when the temperature is low.
• the wings will be more or less inefficient, but this is of no consequence as long as they are able to continue to operate at the determined maximum effect.
• a marked energy gain is attainable, at least 2-3% or more, depending on local conditions, and furthermore, it will eliminate the need to execute the said summer and wintertime operational service adjustments.
• the wings may be arranged with telescope-like fixed wing tips which are kept retracted at low temperatures, but which are unfolded outwards gradually in step with ris ⁇ ing temperatures. This also ensures that an optimizing of the wings occurs without risking overload.
• the wings may be turned slightly for a suitable change of the effective inclination angle, which should be reduced the colder the air is, such that the wings will stall at an even earlier point.
• the wings may still retain the fixed-wing characteristics, since all it takes is for a turning joint and a temperature-sensitive rotation actuator to be placed between the wing blade and the wing base.
• a combination of various regulation means may be implimented, as required, depending on the desired de ⁇ gree of accuracy in the effect equalization between high and low air temperatures.
• Fig. 1 is a perspective view of a windmill with an arrangement according to the invention.
• Figs. 2 and 3 are sectional views of a wing with the arrangement depicted in two different positions.
• Figs. 4 and 5 are corresponding views to illustrate another embodiment of the arrangement according to the invention.
• Fig. 6 is a longitudinal sectional view of same
• Fig. 7 is a front view of a wing according to yet another embodiment of the invention.
• Fig. 8 is a schematic perspective view of a third embodiment of the invention.
• the mill illustrated in Fig. l is of a type having fixed, i.e. non-adjustable wings 2, and according to the invention these are made with some specific, schemati ⁇ cally illustrated front edge areas 4. These may be inte ⁇ grated areas; however, as depicted on the lefthand side of the view, add-on units 6 could be considered which are shaped to fit onto the wing front edge and may be fixated to this, e.g. by gluing means.
• Figs. 2 and 3 are shown in a cross sectional view. It consists of a semi-rigid, pre ⁇ ferably rubber elastic material 8 which, when mounted, forms an aerodynamic extension of the wing front edge. Embedded in the material are some heat-expanding elements 10, which are illustrated in Fig. 2 in a "hot" state, e.g. at 40°C, where the profile surface exhibits its ordinary, effective form. In Fig. 2, the elements 10 are depicted at a relatively low temperature for the
• a longitudinal, V-shaped front edge rail 14 which is displaceable in its longisudinal direction by means of a temperature responsive actuator 16 of a known type, and which is wedge-supported against a rigid rail 18 such that the rail 14 will remain in its retracted position, at high temperatures, as shown in Fig. 4, whilst, at low temperatures, it will assume a projecting position, as shown in Fig. 5.
• the rail 14 may be kept in place by the frontwise positioned, slotted part of the member material 8 which will merely curve outwards ela- stically when the rail 14 is guided into its projecting position.
• the rail 18 form the displaceable element by means of which an I-shaped rail 14 may be displaced forwards and backwards in a straight line, and the actuator 16 is preferably placed behind the rail 18 whereby the element 6 may remain active practically throughout its entire length.
• a tip exten ⁇ sion will manifest itself, in terms of area, as the square on the extension and will thusly be effective for even a modest displacement.
• the wings are normally dimensioned or adapted in correlation with the low temperatures where the impact is the strongest, but where it, in consequence, becomes necessary to relinquish the extra effect which will not be exploitable at high tempera ⁇ tures without the special thermal control arrangement.
• Such an embodiment with a projectable wing tip is il lustrated in Fig. 7 where the wing tip portion 20 covers the fixed wing tip and is projectable to the shown position marked by dotted lines, in that a tempe ⁇ rature-sensitive actuator 22 is placed inside the wing or optionally in the very wing tip portion 20.
• Fig. 8 illustrates that the wing 2, at its base portion 24, may be turnably lodged in a socket 26 which supports the wing mounting flange 28.
• a socket 26 which supports the wing mounting flange 28.
• a radial peg 32 extends and is connected to the base portion 24.
• the extreme end of this peg is coupled to a driving rod on a thermal actua ⁇ tor 34 which is firmly connected to the socket 26.
• Fol ⁇ lowing this, the wing blade 2 is turnably adjusted ac ⁇ cording to the temperature, e.g. by a 1-3° angle so that the inclination angle is increased the hotter the tem ⁇ perature is.

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• Engineering & Computer Science (AREA)
• Life Sciences & Earth Sciences (AREA)
• Sustainable Development (AREA)
• Sustainable Energy (AREA)
• Chemical & Material Sciences (AREA)
• Combustion & Propulsion (AREA)
• Mechanical Engineering (AREA)
• General Engineering & Computer Science (AREA)
• Physics & Mathematics (AREA)
• Fluid Mechanics (AREA)
• Wind Motors (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=8100525

Family Applications (1)

Country Status (3)

Cited By (9)

Citations (5)

• 1992
  • 1992-08-26 DK DK921059A patent/DK105992D0/da not_active Application Discontinuation
• 1993
  • 1993-08-26 WO PCT/DK1993/000279 patent/WO1994004820A1/en not_active Ceased
  • 1993-08-26 AU AU49447/93A patent/AU4944793A/en not_active Abandoned

Patent Citations (5)

Non-Patent Citations (1)

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