DK171738B1 - Wind turbine rotor with at least three blades - Google Patents
Wind turbine rotor with at least three blades Download PDFInfo
- Publication number
- DK171738B1 DK171738B1 DK167790A DK167790A DK171738B1 DK 171738 B1 DK171738 B1 DK 171738B1 DK 167790 A DK167790 A DK 167790A DK 167790 A DK167790 A DK 167790A DK 171738 B1 DK171738 B1 DK 171738B1
- Authority
- DK
- Denmark
- Prior art keywords
- wind turbine
- turbine rotor
- main shaft
- rotor
- hub
- Prior art date
Links
- 229920001971 elastomer Polymers 0.000 claims description 8
- 239000000806 elastomer Substances 0.000 claims description 4
- 238000005452 bending Methods 0.000 description 5
- 238000010276 construction Methods 0.000 description 3
- 230000005284 excitation Effects 0.000 description 2
- 239000000463 material Substances 0.000 description 2
- 229910000831 Steel Inorganic materials 0.000 description 1
- 230000003321 amplification Effects 0.000 description 1
- 230000008878 coupling Effects 0.000 description 1
- 238000010168 coupling process Methods 0.000 description 1
- 238000005859 coupling reaction Methods 0.000 description 1
- 238000013016 damping Methods 0.000 description 1
- 230000005611 electricity Effects 0.000 description 1
- 238000003199 nucleic acid amplification method Methods 0.000 description 1
- 230000010355 oscillation Effects 0.000 description 1
- 230000002787 reinforcement Effects 0.000 description 1
- 239000010959 steel Substances 0.000 description 1
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
- F03D1/00—Wind motors with rotation axis substantially parallel to the air flow entering the rotor
- F03D1/06—Rotors
- F03D1/065—Rotors characterised by their construction elements
- F03D1/0658—Arrangements for fixing wind-engaging parts to a hub
-
- 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
Landscapes
- 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)
- Wind Motors (AREA)
Description
i DK 171738 B1in DK 171738 B1
VINDMØLLEROTOR MED I DET MINDSTE TRE VINGERWind turbine rotor with at least three blades
Opfindelsen angår en vindmøllerotor med i det mindste tre vinger, hvilken vindmøllerotor er indrettet til at kunne 5 rotere om en i det væsentlige vandret hovedaksel og at kunne krøjes i forhold til vindretningen om en i hovedsagen lodret krøjeakse, hvilke vinger strækker sig radialt ud fra hovedakslen og er sluttet til denne via et vingenav.BACKGROUND OF THE INVENTION 1. Field of the Invention The invention relates to a wind turbine rotor having at least three blades, the wind turbine rotor being adapted to rotate about a substantially horizontal main shaft and to be able to bend relative to the wind direction of a substantially vertical bending axis extending radially from the main shaft. and is connected to it via a wing hub.
10 Ved normale aksel-nav forbindelser i tre-bladede vindmøller fastgøres vingenavet på hovedakslen med en flangesamling, med krympeelementer, med en traditionel feder-not samling eller lignende forbindelser. Stivheden af denne fastgørelse vil som regel være stor, og egenfrekvensen for svingninger 15 af rotoren i nikke- og krøjeretning vil være bestemt ikke af stivheden i aksel-nav samlingen, men af stivheden af vingerne, hovedakslen, maskinrammen og tårnet.10 In normal shaft hub connections in three-blade wind turbines, the wing hub of the main shaft is secured with a flange assembly, with shrinkage members, with a traditional spring-not assembly or similar connections. The rigidity of this attachment will usually be high, and the intrinsic frequency of oscillations 15 of the rotor in the nodal and bending direction will be determined not by the rigidity of the shaft hub assembly, but by the stiffness of the wings, main shaft, machine frame and tower.
Med den stive forbindelse opnås god kontrol over rotorens 20 dynamik, så der kun sjældent er risiko for ukontrollable resonansfænomener. Til gengæld overføres lasterne fra rotoren direkte til hovedakslen ved den stive aksel-nav samling. Desuden er sammenhængen mellem stivheden af de øvrige konstruktionsdele på moderne vindmøller oftest sådan, at 25 der er risiko for sammenfald mellem egenfrekvensen for rotoren og en af de grundlæggende excitationsfrekvenser, nemlig frekvensen for bladpassage af tårnet. Derfor optræder hyppigt ret store forstærkninger af de ydre laster på grund af vindmøllens egen dynamik.With the rigid connection good control of the dynamics of the rotor 20 is obtained, so that there is only rarely a risk of uncontrollable resonance phenomena. In turn, the loads are transferred from the rotor directly to the main shaft by the rigid shaft-hub assembly. In addition, the relationship between the stiffness of the other structural parts of modern wind turbines is most often such that there is a risk of coincidence between the rotor intrinsic frequency and one of the basic excitation frequencies, namely the frequency of blade passage of the tower. Therefore, quite often large reinforcements of the external loads occur due to the wind turbine's own dynamics.
3030
Man har forsøgt at afhjælpe disse ulemper på forskellig måde.These drawbacks have been tried in various ways.
Således er det fra beskrivelsen til DK patentansøgning nr.Thus, from the description to DK patent application no.
35 4225/79 og fra DE fremlæggelsesskrift nr. 26 55 026 kendt at indskyde en ledforbindelse mellem vindmøllerotoren og DK 171738 B1 2 hovedakslen, hvorved en mængde af de uønskede kræfter mellem vindmøllerotor og tårnet, hvorpå vindmøllen med vindmøllerotoren er lejret, kan elimineres.35 4225/79 and from DE-presenting publication no. 26 55 026 known to insert a link between the wind turbine rotor and the main shaft, whereby an amount of the undesirable forces between the wind turbine rotor and the tower on which the wind turbine with the wind turbine rotor is mounted can be electrically mounted.
5 I begge de anførte skrifter er vindmøllerotoren forsynet med to vinger, og der er tale om en ledforbindelse, hvor der ikke forekommer nogen anden oprettende kraft end centrifugalkraften på systemet. Skulle man udføre de pågældende løsninger på en tre- eller flerbladet vindmølle, ville 10 man imidlertid løbe ind i det problem, at rotoren på vindmøllen ville præcessere. Dette fænomen ville optræde, da der på en trebladet vindmølle er nødt til at være en frihedsgrad mere end på en tobladet vindmølle - ellers ville den trebladede rotor kun være fri om en af de nødvendige to 15 akser. Forskellen mellem møllenavene for en tobladet og en tre- eller flerbladet konfiguration er med andre ord, at hvor der for den tobladede mølle, beskrevet i DK patentansøgning nr. 4225/79, opnås ledeløshed med et hængsel, kræver en tre- eller flerbladet vindmølle et kardanled for at 20 opnå ledeløshed, som det er beskrevet i DE fremlæggel ses-skrift nr. 26 55 026.5 In both of the aforementioned writings, the wind turbine rotor is provided with two blades, and this is an articulated joint in which there is no other creating force than the centrifugal force on the system. However, should the solutions in question be performed on a three- or multi-blade wind turbine, one would run into the problem that the rotor on the wind turbine would be more precise. This phenomenon would occur, since on a three-blade wind turbine there must be a degree of freedom more than on a two-blade wind turbine - otherwise the three-blade rotor would be free only on one of the necessary two axes. In other words, the difference between the mill hubs for a two-blade and a three- or multi-blade configuration is that where for the two-blade mill described in DK patent application no. in order to achieve leaderlessness, as described in DE submission no. 26 55 026.
Indføres der imidlertid et kardanled, er der for vindmøllerotoren ikke nogen præference for en bestemt rotationsakse, 25 og den kan lige så godt rotere om en vilkårlig anden akse, som den kan rotere omkring den akse, der beskrives af møllens hovedaksel. Man vil da se, at rotoren giver sig til at præcessere, og der vil snart opstå en situation, hvor der bliver stor afvigelse mellem rotationsakserne, hvilket i 30 sidste ende kan føre til, at vingerne rammer mølletårnet.However, if a universal joint is introduced, the wind turbine rotor has no preference for a particular axis of rotation, and it can rotate as well about any other axis as it can rotate about the axis described by the main axis of the mill. It will then be seen that the rotor lends itself to precision, and a situation will soon arise where there is a large deviation between the rotary axes, which may eventually lead to the blades hitting the mill tower.
Det er formålet for opfindelsen at angive en sådan udformning af en vindmøllerotor med i det mindste tre vinger, at de ovennævnte ulemper elimineres.It is the object of the invention to provide such a design of a wind turbine rotor with at least three blades to eliminate the above disadvantages.
3535
Dette formål opnås ved en vindmøllerotor af den indled- DK 171738 Bl 3 ningsvist angivne art, hvilken vindmøllerotor ifølge opfindelsen er særegen ved, at det fleksible led er fjederbelastet med en lille fjederkonstant mod en stilling, hvor rotorakslen flugter med hovedakslen.This object is achieved by a wind turbine rotor of the kind specified, which wind turbine rotor according to the invention is peculiar in that the flexible joint is spring loaded with a small spring constant against a position where the rotor shaft flushes with the main shaft.
5 I et fleksibelt led med en vis fjederkonstant vil fjedervirkningen tjene til at rette rotoren ind i rotorplanet vinkelret på hovedakslen, og muligheden for, at rotoren kan svinges i en bane med stor amplitude i forhold til rotor-10 planet vinkelret på hovedakslen, formindskes, hvorved også risikoen for, at vingerne kan ramme vindmøllens tårn, nedsættes .In a flexible joint with a certain spring constant, the spring action will serve to direct the rotor into the rotor plane perpendicular to the main shaft, and the possibility that the rotor can be pivoted in a path of high amplitude relative to the rotor plane perpendicular to the main shaft is reduced. thereby also reducing the risk of the blades hitting the wind turbine tower.
Ved det fleksible led ifølge opfindelsen vil der overføres 15 en vis del af bøjningsmomenterne fra rotoren til hovedakslen, men belastningerne vil være mindre end i den traditionelle konstruktion med en stiv forbindelse. Der overføres således mindre laster fra vindmøllerotoren til maskinkonstruktion og tårn. Maskinkonstruktionen dimensioneres af 20 rotorlasterne, og ved at reducere disse, kan en given konstruktion bære en større rotor, og derved blive mere rentabel. Tilsvarende kan en given rotor monteres på en spinkle-re maskinkonstruktion.At the flexible joint according to the invention, a certain part of the bending moments will be transferred from the rotor to the main shaft, but the loads will be less than in the traditional structure with a rigid connection. Thus, smaller loads are transferred from the wind turbine rotor to machine construction and tower. The machine structure is dimensioned by the 20 rotor loads, and by reducing these, a given structure can carry a larger rotor, thereby becoming more profitable. Similarly, a given rotor can be mounted on a flimsy machine structure.
25 Med et fleksibelt led med en vis fjederkonstant kan der foretages en beregning af de resulterende egenfrekvenser i nikke- og krøjeretning, og det kan sikres, at egenfrekvenserne ligger i et område med lille forstærkning af de grundlæggende excitationsfrekvenser.25 With a flexible joint with a certain spring constant, the resulting self-frequencies can be calculated in the nodal and bending directions, and it can be ensured that the self-frequencies are in a region with little amplification of the basic excitation frequencies.
3030
Fjederkonstanten kan opnås ved at udføre det fleksible led med gummielementer eller andre elastomerer, eller med stålfjedre eller lignende elementer, hvor det så kan være nødvendigt at tilføje dæmpning.The spring constant can be obtained by performing the flexible joint with rubber elements or other elastomers, or with steel springs or similar elements where it may be necessary to add damping.
3535
Det fremgår af det foran anførte, at princippet i opfindel- DK 171738 B1 4 sen kendes fra to-bladede vindmøller, hvor det hyppigst er set realiseret med et hængselled uden fjederkonstant mellem nav og hovedaksel. Derimod kendes princippet ikke fra trebladede vindmøller, hvor der kræves frihed omkring to ak-5 ser. Netop for at opnå fordelene ved, at der ikke overføres bøjningsmomenter til hovedakslen, benyttes den to-bladede konstruktion med hængselled (eng.: Teetered Hub) ofte på store vindmøller. Prisen for denne fordel er til gengæld, at de dynamiske forhold ved to-bladede vindmøller kan være 10 sværere at kontrollere, eftersom en to-bladet konstruktion ikke har et rotationssymmetrisk masseinertimoment for rotoren.It is apparent from the foregoing that the principle of the invention is known from two-blade wind turbines, where it is most often realized with a hinge joint without spring constant between hub and main shaft. By contrast, the principle is not known from three-blade wind turbines, where freedom is required around two axes. Precisely in order to obtain the advantages of not transferring bending moments to the main shaft, the two-blade construction with a teetered hub is often used on large wind turbines. The cost of this advantage, on the other hand, is that the dynamic conditions of two-blade wind turbines may be more difficult to control since a two-blade construction does not have a rotationally symmetric mass inertia moment for the rotor.
Ved visse mindre tre-bladede vindmøller er det samme formål 15 ‘ opfyldt ved at hængsle hvert enkelt blad individuelt på navet, hvorved bladet indstiller sig i en vinkel mod rotorplanet. Størrelsen af denne vinkel bestemmes af forholdet mellem vindtryk og centrifugalkraft. På større vindmøller kan dette princip imidlertid kun vanskeligt udnyttes, ef-20 tersom rotorhastigheden bliver for langsom til at give centrifugalkræfter, der er store nok til at kompensere for vindtrykket, uden at vinklen mellem blad og rotorplan bliver for stor.For certain smaller three-blade wind turbines, the same purpose is achieved by attaching each blade individually to the hub, the blade adjusting at an angle to the rotor plane. The magnitude of this angle is determined by the relationship between wind pressure and centrifugal force. However, on larger wind turbines, this principle can be difficult to utilize only if the rotor speed becomes too slow to produce centrifugal forces large enough to offset wind pressure without the angle between blade and rotor plane becoming too large.
25 Vindmøllerotoren ifølge opfindelsen skal forklares nærmere i det følgende under henvisning til tegningen, hvor der vises et delvist snit i en foretrukken udførelsesform for en vindmøllerotor ifølge opfindelsen.The wind turbine rotor according to the invention will be explained in more detail below with reference to the drawing, in which a partial section is shown in a preferred embodiment of a wind turbine rotor according to the invention.
30 ' Vindmøllerotoren er i sin helhed angivet ved henvisningsbetegnelsen 20 og er indrettet til gennem en hovedaksel 1 at drive en på tegningen ikke vist generator til frembringelse af elektricitet.The wind turbine rotor is indicated in its entirety by reference numeral 20 and is adapted to drive through a main shaft 1 a generator not shown in the drawing for generating electricity.
35 Vindmøllerotoren 20 er sammen med generatoren anbragt i et hus på toppen af et tårn, og huset kan drejes eller krøjes DK 171738 B1 5 i forhold til vindretningen om en lodret krøjeakse.The wind turbine rotor 20, together with the generator, is arranged in a housing at the top of a tower, and the housing can be rotated or curved relative to the wind direction of a vertical pitch axis.
Hverken huset, tårnet eller krøjeaksen er for overskuelighedens skyld vist på tegningen.For the sake of clarity, neither the house, the tower, nor the axle is shown in the drawing.
55
Hovedakslen 1 bærer på den bort fra generatoren vendende ende en medbringerplade 2, der er udrejeligt fastgjort til hovedakslen 1.The main shaft 1 carries on the end facing away from the generator a carrier plate 2 which is pivotally attached to the main shaft 1.
10 På medbringerpladen 2 er anbragt et antal medbringertappe 3, der er anbragt med ensartet vinkelafstand i en cirkel koncentrisk med hovedakslen 1. Antallet af medbringertappe 3 kan variere efter behov og kan være fra tre til tolv stykker.10 On the carrier plate 2 are arranged a plurality of carrier pins 3 disposed at uniform angular distance in a circle concentric to the main shaft 1. The number of carrier pins 3 may vary as needed and may be from three to twelve.
15 På hovedakslen 1 er anbragt en ring 5 af en elastomer, såsom gummi eller et lignende materiale, og på denne elastomere ring 5 hviler et vingenav 6, der har anlægsflader 10 for en fastgørelsesflange 9 på en vinge 8.15 On the main shaft 1 is mounted a ring 5 of an elastomer, such as rubber or a similar material, and on this elastomeric ring 5 rests a wing hub 6 having abutment faces 10 for a fastening flange 9 on a wing 8.
2020
Antallet af vinger kan, som antydet på tegningen, være tre, som er anbragt ækvidistant, dvs. ved tre vinger med en indbyrdes vinkel på 120°.The number of wings, as indicated in the drawing, may be three equidistant, i.e. at three blades with a mutual angle of 120 °.
25 Vingerne 8 fastgøres ved hjælp af deres flange 9 til de respektive anlægsflader 10, for eksempel ved hjælp af bolte 11, der føres gennem dertil beregnede boringer langs kanten af flangen 9 og ind i med gevind forsynede boringer i vin-genavet 6.The wings 8 are secured by their flange 9 to the respective abutment surfaces 10, for example by means of bolts 11 which are passed through intended bores along the edge of the flange 9 and into threaded bores in the wine hub 6.
3030
Hver medbringertap 3 er forsynet med en bøsning 4 af en elastomer, såsom gummi eller et lignende materiale, og bøsningernes 4 ydre overflade er fortrinsvist sfærisk.Each carrier pin 3 is provided with a sleeve 4 of an elastomer, such as rubber or a similar material, and the outer surface of the sleeves 4 is preferably spherical.
35 . Medbringertappene 3 med deres bøsninger 4 griber ind i bundhuller 7, der er frembragt i den mod medbringerpladen 2 DK 171738 B1 6 vendende side af vingenavet 6.35. The driver pins 3, with their bushings 4, engage in bottom holes 7 formed in the side of the wing hub 6 facing the carrier plate 2 DK 171738 B1 6.
Medbringertappene 3 og bøsningerne 4 tjener derfor sammen med ringen 5 til at styre vingenavet 6 med vingerne 8 i 5 forhold til hovedakslen 1 og overfører vindmøllerotorens drejning til hovedakslen 1, idet de nævnte elastomere dele 4, 5 samtidig udgør en fleksibel forbindelse.Therefore, the driver pins 3 and the bushings 4 together with the ring 5 serve to steer the wing hub 6 with the wings 8 in relation to the main shaft 1 and transmit the rotation of the wind turbine rotor to the main shaft 1, said elastomeric parts 4, 5 simultaneously forming a flexible connection.
Denne fleksible forbindelse frembringer en fjedervirkning, 10 der udøver en oprettende kraft på vindmøllerotoren 20, hvorved det undgås, at denne kan rotere om en rotationsakse, der afviger fra den påtænkte rotationsakse, der er fastlagt ved hovedakslen.This flexible connection produces a spring action 10 exerting an actuating force on the wind turbine rotor 20, thereby preventing it from rotating about a axis of rotation that deviates from the intended axis of rotation set at the main axis.
15 De sfæriske bøsninger 4 på medbringertappene 3 virker som en medbringerkobling, og ringen 5 overfører vindtrykket ved forskydning og danner vingenavets 6 andet støttepunkt. Ved tilpasning af ringens 5 stivhed kan navforbindelsens fleksibilitet afpasses efter forholdene for en bestemt vindmøl-20 le.The spherical bushes 4 on the carrier pins 3 act as a carrier coupling, and the ring 5 transmits the wind pressure by shear and forms the second support point of the wing hub 6. By adjusting the stiffness of the ring 5, the flexibility of the hub connection can be adjusted to the conditions of a particular wind turbine.
Claims (3)
Priority Applications (3)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK167790A DK171738B1 (en) | 1990-07-11 | 1990-07-11 | Wind turbine rotor with at least three blades |
| AU82278/91A AU8227891A (en) | 1990-07-11 | 1991-07-11 | Windmill rotor with at least three wings |
| PCT/DK1991/000202 WO1992001157A1 (en) | 1990-07-11 | 1991-07-11 | Windmill rotor with at least three wings |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK167790 | 1990-07-11 | ||
| DK167790A DK171738B1 (en) | 1990-07-11 | 1990-07-11 | Wind turbine rotor with at least three blades |
Publications (3)
| Publication Number | Publication Date |
|---|---|
| DK167790D0 DK167790D0 (en) | 1990-07-11 |
| DK167790A DK167790A (en) | 1992-01-12 |
| DK171738B1 true DK171738B1 (en) | 1997-04-21 |
Family
ID=8107127
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK167790A DK171738B1 (en) | 1990-07-11 | 1990-07-11 | Wind turbine rotor with at least three blades |
Country Status (3)
| Country | Link |
|---|---|
| AU (1) | AU8227891A (en) |
| DK (1) | DK171738B1 (en) |
| WO (1) | WO1992001157A1 (en) |
Families Citing this family (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| FR2850137A1 (en) * | 2003-01-16 | 2004-07-23 | Afelec | Wind turbine head, has blades assembled in hub for their natural movement with respect to rotor plane against compression resistance of elastic mass, which is supported against blade ends and hub |
| CN103982373B (en) * | 2014-05-30 | 2016-08-24 | 北京金风科创风电设备有限公司 | Wind turbine |
Family Cites Families (4)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US2360791A (en) * | 1941-03-22 | 1944-10-17 | Morgan Smith S Co | Wind turbine |
| US4083651A (en) * | 1976-08-17 | 1978-04-11 | United Technologies Corporation | Wind turbine with automatic pitch and yaw control |
| DE2655026C2 (en) * | 1976-12-04 | 1979-01-18 | Ulrich Prof. Dr.-Ing. 7312 Kirchheim Huetter | Wind energy converter |
| US4316698A (en) * | 1979-08-23 | 1982-02-23 | Bertoia Val O | Fluid-driven turbine with speed regulation |
-
1990
- 1990-07-11 DK DK167790A patent/DK171738B1/en not_active IP Right Cessation
-
1991
- 1991-07-11 WO PCT/DK1991/000202 patent/WO1992001157A1/en unknown
- 1991-07-11 AU AU82278/91A patent/AU8227891A/en not_active Abandoned
Also Published As
| Publication number | Publication date |
|---|---|
| WO1992001157A1 (en) | 1992-01-23 |
| DK167790D0 (en) | 1990-07-11 |
| DK167790A (en) | 1992-01-12 |
| AU8227891A (en) | 1992-02-04 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| B1 | Patent granted (law 1993) | ||
| PBP | Patent lapsed | ||
| B1 | Patent granted (law 1993) | ||
| PBP | Patent lapsed |
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