WO2010018590A1 - Horizontal axis wind turbine - Google Patents

Horizontal axis wind turbine Download PDF

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Publication number
WO2010018590A1
WO2010018590A1 PCT/IN2009/000172 IN2009000172W WO2010018590A1 WO 2010018590 A1 WO2010018590 A1 WO 2010018590A1 IN 2009000172 W IN2009000172 W IN 2009000172W WO 2010018590 A1 WO2010018590 A1 WO 2010018590A1
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WO
WIPO (PCT)
Prior art keywords
wind turbine
high efficiency
tower
horizontal axis
axis wind
Prior art date
Application number
PCT/IN2009/000172
Other languages
French (fr)
Inventor
Yogesh Sonar
Original Assignee
Yogesh Sonar
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Yogesh Sonar filed Critical Yogesh Sonar
Publication of WO2010018590A1 publication Critical patent/WO2010018590A1/en

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Classifications

    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03DWIND MOTORS
    • F03D7/00Controlling wind motors 
    • F03D7/02Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor
    • F03D7/0296Controlling wind motors  the wind motors having rotation axis substantially parallel to the air flow entering the rotor to prevent, counteract or reduce noise emissions
    • FMECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F03MACHINES OR ENGINES FOR LIQUIDS; WIND, SPRING, OR WEIGHT MOTORS; PRODUCING MECHANICAL POWER OR A REACTIVE PROPULSIVE THRUST, NOT OTHERWISE PROVIDED FOR
    • F03DWIND MOTORS
    • F03D15/00Transmission of mechanical power
    • YGENERAL 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
    • Y02TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02EREDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E10/00Energy generation through renewable energy sources
    • Y02E10/70Wind energy
    • Y02E10/72Wind turbines with rotation axis in wind direction

Definitions

  • the present invention relates to a horizontal axis wind turbine and more particularly problem generated by high efficiency rotor, such as Tower vibration, Rotor racing, Tilting of rotor axle, Shocks by Wind gust, Gyroscopic effect, Material fatigue, Overloading, Friction & RPM limitation etc.
  • high efficiency rotor such as Tower vibration, Rotor racing, Tilting of rotor axle, Shocks by Wind gust, Gyroscopic effect, Material fatigue, Overloading, Friction & RPM limitation etc.
  • Wind turbines are well known devices used to extract energy from the wind.
  • This one source is non ⁇ conventional even though not widely use due to high investment & expensive to maintain.
  • tail set at offset distance from yaw pivot point to control on over speed.
  • rotor area regarding wind direction minimizes with increases wind speed means above rated-wind-speed, it means wind power after rated-wind-speed has spilled due to tail, in short power coefficient drastically decrease after rated-wind-speed. This one is drawback of small wind turbine.
  • Concentrating wind Turbine (three blades) rotor & Enflo wind turbine has efficiency more than the Bet'z theoretical limit (59.9).
  • Another high efficiency rotor technology such as two and one blade rotor, which has efficiency near about 45%.
  • Such type of rotor has high RPM, that's why another high RPM related problems are generated as stated above, thereby such high efficiency rotor are not comfortable for large scale.
  • the present invention is developed in view of the above problems regarding the conventional technology.
  • the principle object of this invention is to make such Wind Turbine, which has Low Cost, High Efficiency & Very Low Maintenance.
  • Another object of this invention is the system work very well by means without resisting high RPM related problems. It means the rotor can rotate/racing to gain there natural optimum efficiency irrespective of its RPM, mis all be done by using simple passive system.
  • tail vane effect - In small wind turbine designs, tail vane is set at the back of rotor. Therefore tail vane vibrates due to shadow effect of rotor. These vibrations of tail vane transmit in whole system thereby whole system gets affected.
  • the present invention is a downwind type wind turbine but work as upwind type wind turbine therefore this wind turbine not depends on tail vain to take a direction of rotor toward wind flow, but in present wind turbine tail vain is provided to make rotor direction toward wind direction as early as possible, to minimize power loss.
  • vane is set at back of rotor with flexible attachment 5 thereby vibration controls or absorb and do not affect the whole system.
  • Fig 1 IA The working examples of present wind turbine on resonance vibrations means has shown in Fig 1 IA, and at high wind speed example shown in Fig 1 IB.
  • tower is safe from Shocks, Gust, Cyclic stress, Vibration etc. Therefore tower does not get fatigue or suddenly overload that's why it does not need a very high strength tower.
  • lattice type tower is preferred which has low cost and broad base means.
  • Fig IA shows three dimensional view of wind turbine according to the present invention.
  • Fig IB shows full assembly in front view, side view and top view of the wind turbine according to the present invention.
  • Fig 2 shows close up of three dimensional view of wind turbine head (all components above vertical bearing) according to the present invention.
  • Fig 3A illustrates internal component of nacelle according to the present invention.
  • Fig 3B shows Rotor Axle close up of Fig 3 A.
  • Fig 3C shows axle bearing surrounded by numbers of spring of FIG 3 A.
  • Fig 4 shows front, side & top views of vane with there clause up of FIG 1.
  • Fig 5 illustrate front, side & top views of Counter Weight with there internal component position such as Generator & Gear Box of the wind turbine according to the present invention.
  • Fig 6 shows front, side & top views of Horizontal Level Unit the wind turbine according to the present invention.
  • Fig 7 shows front, side & top views of Main Universal Joint according to the present invention.
  • Fig 8 shows compressive spring & two universal joints attached to both ends of spring according to the present invention.
  • Fig 9 illustrate power transmission component according to the present invention.
  • Fig 10 shows front, side & top view of sliding joint and; universal joint which ended on both side of sliding joint according to the present invention.
  • Fig HA illustrate an example of side-to-side coinciding vibration (resonance frequency) condition of wind turbine head according to the present invention.
  • Fig HB illustrate an example of side-to-side vibration at high RPM by means at High wind speed (High wind speed means wind speed more than resonance frequency's wind speed) where amplitude has short with high frequency of wind turbine head according to the present invention.
  • Fig HC illustrate an example of back & forth (vibration along axle) coinciding vibration with there close up of wind turbine head according to the present invention.
  • Fig 12 illustrate top view of wind turbine head, shows vibrations of vane and base point (center of vertical bearing) from where head can revolve at 360° according to the present invention.
  • Fig 13 illustrate some turning phases of wind turbine head, shows when wind direction suddenly flow from cross direction then head of wind turbine turn to opposite direction to line up with new wind flow; here turning points shown by thin circle, according to the present invention.
  • Wind Speed (wind speed more than resonance wind speed) ⁇ l - Deflection of Sub-Tower from mean position at High Wind
  • Wind power is non conventional source of energy due to high investment and expensive to maintain in such plants this source is not widely use. Vibration, Gyration, Gust etc are the main reasons of high investment.
  • vibrations are at any phase are controlled up to there resonance vibrations and also controlled gyroscopic & gust effect.
  • This system avoids the complicated system like Yaw control, Pitch control etc. Therefore the cost and maintenance cost of this system will be least.
  • Nacelle 1 - Nacelle 1 comprises rotor axle 16 in such way that can axle 16 vibrate to manage tilting or gyroscopic effect & low scale back impact, wherein axle 16 holding by two bearing 1.2 & such bearing surrounded by numbers of spring 13 to manage tilting effect, one bole joint LS attached to the end of the axel 16, bole joint LS supported by spring 1.6 to manage low scale back impact due to gust or fluctuation of wind flow, at central portion of axle 16 one driver bevel gear 1 ⁇ has attached to transmit power from axle 16 to driven bevel gear 1.7, driven bevel gear 1.7 supported by back side bearing 1.2 with the help of supporting component 1.8, driven bevel gear 1.7 forward power with vibration to universal joint which linked with Linear Sliding Joint.
  • Sub Tower 2 - nacelle 1 mounted on sub tower 2; and sub tower 2 means comprises two solid parallel plates which are mounted on base of head 6 with the help of main universal joint 17. Thereby bottom end of sub tower 2 works as base point and top end movement up to some limit at horizontal plain means, mean position maintain by supporting number of spring 3, 13 means.
  • Two parallel plates of sub tower 2 are parallel with wind direction thereby wind flow easily passes through sub tower 2 by means wake or shadow effect are negligible means in other ward cyclic effect negligible here; and such parallel plates give high structural strength as compare to tubular shape tower.
  • sub-tower 2 two parallel plates
  • main tower 10 & sub tower 2 are not in one line thereby this one is downwind type wind turbine but work like as up-wind type wind turbine.
  • Main Back Spring 3 This main back spring 3 used to absorb or control back and forth movements or vibrations or shocks of sub-tower 2 thereby nacelle 1.
  • One end of this spring mounted on Base of Head 6 and another end to back side sub- tower 2 with the help of two universal joints 19.
  • Vane 4 - Vane 4 attached to back side of Base of Head 6. Vane 4 is flexible up to some limit with help of number of spring 5.7 to avoid there vibration to transmits in whole system.
  • a Guide Plat 4.1 attached at back side of vane 4 to guide vane 4, when wind flow suddenly flow from opposite wind direction.
  • the present invention is down-wind type wind turbine therefore rotor automatically line up with wind direction. But its need to line up with wind direction at very short time to avoid power loss. In account such problem, vane 4 has given, to line up rotor as early as possible to avoid power loss. Second reason is when wind direction suddenly flow from opposite (back / rear side) direction than rotor spine with opposite direction to avoid such loss vane is provided. The working of this vane at opposite wind flow has shown in Fig 13 with the help of some number of phases, in first phase Vane Guide Plat 4.1 mismatch with wind direction, because Vane Guide Plat 4.1 is one side edge plate, thereby vane turn one side shown in second phase, another phase shows remaining steps regarding line up with cross wind direction. Reference Fig 1, Fig 2, Fig 4, Fig 12, Fig 13.
  • Base of Head 6 - Main tower 10 & sub tower 2 are not in one line there extension distance covered by using a plat means know as Base of Head 6, means this plat is holding device especially for universal joint 17 (thereby sub tower 2 ), side spring 13 , main back spring 3 & vane 4 etc.
  • Base of Head 6 means this plat is holding device especially for universal joint 17 (thereby sub tower 2 ), side spring 13 , main back spring 3 & vane 4 etc.
  • Supporter 7 - This one is supporting plate for Base of Head 6.
  • Main Vertical Bearing 8 This one is vertical roller bearing thereby head can rotate at 360° and provide strong support.
  • Horizontal Level unit 9 This unit helps to set Base of Head 6 horizontal with ground after complete assembly. It has two flange 9.1 attached by three stud 92. Reference Fig 1, Fig 6.
  • Counter Weight 11 The heavy weight generator 11.1 and gear box 11.2 are used as counter weight for balancing means, thereby the weights limitations of generator 11.1 and gear box 11.2 increase and flexibility for regular maintenance.
  • Counter Weight 11 maintain in such way thereby wind force do not effect to rotor direction which lined with wind direction.
  • Counter Weight 11 has triangular bar with tetrahedron ends thereby minimizes resistance of wind flow from front and both sides, Counter Weight 11 attached to base of Head 6 by using two parallel plates 18 ( parallel to ground also) thereby side to side wind flow do not resist to counter Weight 11 .
  • Power Transmission Unit 12 In Power Transmission Unit 12, low speed axle 16 transmit power with all phase vibration, such power provide to gear box 11.2 and/or than generator 11.1 with the help of small universal joints 12.1, connecting roads 12.3 and sliding joints 12.2.
  • Reference Fig 5, Fig 9, Fig 10 [79] Side Spring 13 - This two Side Spring 13 used to absorb or control side-to- side movements or vibrations or shocks of sub-tower 2 thereby nacelle 1.
  • One end of this springs mounted on Base of Head 6 and another end to sub-tower 2 with the help of some universal joints 19.
  • Rotor 15 - This invention prefer high efficiency rotor, such type of high efficiency rotor has high lift to drag ration thereby rotor spine with high RPM, this invention purpose to use such type of high efficiency rotor with controlling there side effect regarding RPM.
  • Present wind turbine involve numbers of innovative steps, some step(s) applicable to solve specific problem(s) of conventional wind turbine such as Tower vibration, Rotor racing, Tilting of rotor axle, Shocks by Wind gust, Gyroscopic effect, Material fatigue, Overloading, Friction & RPM limitation etc.

Abstract

A horizontal axis wind turbine comprises: a tower divided in two parts as a main tower (10) and a sub tower (02) which are not in one line and the extensional distance between which is covered by a guide plate (06); a nacelle (01) mounted on the flexible sub tower (02) so that the nacelle (01) can vibrate at the horizontal plane to manage the horizontal plane overloading effect on the nacelle (01 ); a rotor axle (16) which is flexible for tilting or vibrating in the nacelle (01). Vibrations or shocks of the rotor axle (16) are controlled or absorbed by numbers of springs and the mutual action of the flexible sub tower (02) and the rotor axle (16), thereby vibrations or shocks of the rotor axle (16) are not transmitted to the whole system.

Description

High Efficiency Horizontal Axis Wind Turbine
Technical Field
[1] The present invention relates to a horizontal axis wind turbine and more particularly problem generated by high efficiency rotor, such as Tower vibration, Rotor racing, Tilting of rotor axle, Shocks by Wind gust, Gyroscopic effect, Material fatigue, Overloading, Friction & RPM limitation etc.
Background Art
[2] Wind turbines are well known devices used to extract energy from the wind.
This one source is non^conventional even though not widely use due to high investment & expensive to maintain.
[3] To gain high efficiency, rotor required high lift to drag ratio means it should have high RPM of rotor. But high RPM rotor creates too many problems such as Gyroscopic Effect, Tilting of Rotor Axle, Shocks, Overloads, Vibrations, Frictions, Fatigues, Vibrations Coinciding, Cyclic force, Rotor Racing and RPM Limitations etc.
[4] Too many systems are investigated separately to solve those problems such as
Yaw Control System, Pitch Control System, Gear Box, High Strength Tower, Tilting Hub and Preciseness of Blade etc. But the problems are not well solved up to date. As result by using such complicated computerized preciseness technology, the overall cost & maintenance drastically increased.
[S] Particularly about small wind turbine, tail set at offset distance from yaw pivot point to control on over speed. By using such tail, rotor area regarding wind direction minimizes with increases wind speed means above rated-wind-speed, it means wind power after rated-wind-speed has spilled due to tail, in short power coefficient drastically decrease after rated-wind-speed. This one is drawback of small wind turbine.
[6] Now current technologist continuously trying to increase the diameter of rotor because RMP has low in large diameter rotor as compare to small diameter rotor, that's why the diameter of rotor continuously increases day by day to minimize high RPM related problems as stated above.
[7] In modern wind turbine the power of wind after rated-wind-speed has spilled due to active pitch control system, In short power coefficient drastically decreases after rated wind speed. The pitch control system partly use to avoid high RPM related problems for safe working, but due to this system power spilled after rated^wind- speed this one is major drawback of active pitch control system. To solve this problem, technologist increases diameter of rotor to increase rated-wind-speed because rated-wind-speed increases with increase in diameter of rotor, but due to increase in diameter, cut-ύvspeed also increases. Therefore the power has not extracted from low wind speed, which is unfavorable condition at low wind side. Another drawback of conventional system has very low efficiency near about 20-35% only. There are some other problems like high strength material Tower, Blade & other assembly required. It is also critical to transport & for maintenance etc. That's the reason why those systems are not in local hand.
[8] To minimize overall infrastructure including cost with proper power requirements, it should be necessary to concentrate on efficiency of wind turbine. Actually too many interesting technology of rotor investigated, which has efficiency above than the Bet'z theoretical limit (59.9).
[9] For example, Concentrating wind Turbine (three blades) rotor & Enflo wind turbine has efficiency more than the Bet'z theoretical limit (59.9). Another high efficiency rotor technology such as two and one blade rotor, which has efficiency near about 45%. Such type of rotor has high RPM, that's why another high RPM related problems are generated as stated above, thereby such high efficiency rotor are not comfortable for large scale.
[10] Specially about concentrating wind system, what happens if the wind direction control fails? Terrible drag force occur, perpendicular to the tube axis, And what about the fluctuating wind direction in fraction of a second? If the control of the huge tube is not able to follow absolutely exact a new wind direction, than a separation of flow will occurs at the inner wall of the intake, the result is collapse.
[11] Specially about Two and One-blade wind turbine designs have advantage of saving the cost of one and two rotor blade respectively and its weight, of course. However, they tend to have difficulty in penetrating the market, partly because they require high rotational speed to yield the same energy output. And two and one- bladed machine requires a more complex design with a hinged (teetering hub) rotor. The rotor has to be able to tilt in order to avoid to heavy shocks to the turbine when a rotor blades passes the tower. This arrangement may require additional shocks absorbers to prevent the rotor blade from hitting the tower. [12] Finally it's conclude that high RPM of rotor is the key problem, current technology rich up to 85% efficiency of rotor but not fulfill to control on high RPM related Rotor problem. That's why wind turbine rich to very high investment & expensive to maintenance.
Disclosure of Invention
Technical- Problem
[13] Conventional wind turbine technology has too many problems which are briefly discussed above. Such problems are Gyroscopic effect on rotor axle, Tilting of rotor axle, Shocks and Overload on axle or bearings thereby whole system, Vibrations, Frictions, Fatigues effects on whole structure, Vibration Coinciding, Cyclic force on rotor, Rotor Racing and RPM Limitation etc. To minimize such problems technologist uses too many system such as Yaw Control System, Pitch Control System, Gear Box, High Strength Material Components and Tilting Hub, many types of sensor etc.
[14] But due to overall combination of this complicated system Wind Turbine comes to Low Efficiency, High Cost, and Expensive Maintenances. These are main problems of this Green Power, That's why this power has not widely use at local level.
Technical- Solution
[IS] The present invention is developed in view of the above problems regarding the conventional technology. The principle object of this invention is to make such Wind Turbine, which has Low Cost, High Efficiency & Very Low Maintenance. Another object of this invention is the system work very well by means without resisting high RPM related problems. It means the rotor can rotate/racing to gain there natural optimum efficiency irrespective of its RPM, mis all be done by using simple passive system.
[16] The particular problems & there solution are disclosed in details step by step in the next part (Advantageous Effects)
Advantageous Effects
[17] These are advantageous effects of present wind turbine, described with following points.
Vane effect - In small wind turbine designs, tail vane is set at the back of rotor. Therefore tail vane vibrates due to shadow effect of rotor. These vibrations of tail vane transmit in whole system thereby whole system gets affected. [18] The present invention is a downwind type wind turbine but work as upwind type wind turbine therefore this wind turbine not depends on tail vain to take a direction of rotor toward wind flow, but in present wind turbine tail vain is provided to make rotor direction toward wind direction as early as possible, to minimize power loss. Here vane is set at back of rotor with flexible attachment 5 thereby vibration controls or absorb and do not affect the whole system.
[19] Tower Vibration - In conventional wind turbines the vibrations of rotor axle directly affect the tower and thereby whole system, which results limitations to RPM. In present invention vibrations of rotor are controlled by spring control unit thereby such vibrations do not transmits in the whole system. It means tower is safe from rotor vibration, therefore rotor spine with there natural optimum efficiency.
[20] Vibrations Coinciding - In conventional wind turbine, vibration coinciding
(Resonance frequency) is one of the harmful condition thereby chances of accident or failure. Pitch Control System or Brakes are use to solve this problem but thereby efficiency decrease.
[21] When wind speed gradually increase, amplitude of vibrations increases with wind speed up to resonance frequency after than amplitude decreases & frequency increases.
[22] In this invention by using springs, all the tolerances set in accordance with amplitude of resonance vibrations. Therefore coinciding vibration does not effect on structure, means this system will work in vibration coinciding conditions without effecting efficiency, thus this design is free from vibrations coinciding.
The working examples of present wind turbine on resonance vibrations means has shown in Fig 1 IA, and at high wind speed example shown in Fig 1 IB.
[23] Gyroscopic Effect - In conventional wind turbine, due to gyroscopic affect on rotor axle of high speed high efficiency rotor axle get tilt or forward backward, by this action axle bearing get overloaded or damaged, and its very critical for replace or maintenance partly because of cost and required time.
[24] In present invention, rotor axle surrounded by number of springs in nacelle thereby axle of rotor is free for tilting & forward backward action. Therefore gyroscopic effect on rotor does not damage, overload, fatigues to axle bearing or structure. See Fig 3A which shows rotor axle surrounded by number of springs in nacelle to manage tilting effect. [25] Gust Effect - Vibrations or overload along rotor axel are produces in gusty wind- In present invention those vibrations & shock are controlled by the Main Back Spring 3 & Nacelle 1, thereby it's need not high strength structure specially tower as compare to conventional wind turbine.
The working examples of present wind turbine on gust effect means has shown in Fig HC.
[26] Friction - In conventional wind turbine, there are many turbine accidents involving fire, generally because of loose bolt & frictional heating. To solve those problem too many sensors and high strength structure uses, means such problems solved by resisting them.
[27] In this invention, by using spring control unit, the system naturally adjust
(flexible) with vibrations, wind gust, gyroscopic effect, overloading etc. Hence nut bolts other assembling units are not loosed or wearied out means there is no friction between two meeting parts. Therefore frictional heating & accidents are avoided.
[28] Fatigues of Blade - In conventional wind turbine blade get fatigues due to cyclic force & vibrations. In this invention, by using spring control unit, the axle of rotor is flexible for vibration and tilting effect at any phase or plane thereby blade do not get overload; and by using two parallel plats as Sub Tower (02) wind flow easily passes, thereby wind blade has negligible cyclic stress, so that the blades don't get overload or fatigues means.
[29] Bearing Life - In conventional wind turbine, due to the shocks & overloading bearings get damaged frequently. It is very costly to repair or change to bearings.
In present invention these shocks & overloading controlled by spring control unit, therefore bearing do not get damaged therby bearing has high life.
[30] Cut-Out-Speed - In conventional wind turbine, the problems generated by high efficiency rotor (high RPM rotor) are not solved e.g. gyroscopic effect, vibrations etc. Thereby such rotor has RPM limitation, that's why such wind turbine has low cut-out- speed.
[31] In present wind turbine, the problems generated by high efficiency rotor are solved, mat's why present wind turbine has high cut-out-speed.
[32] Cut-in-Speed - In conventional wind turbine, if low cut-in-speed rotor is used there shall problems of over thrust & wind gust on the structure at high wind speed. In present wind turbine, by using Back Spring 03 the gust and over thrust are controlled, thereby the use of low cut-in-speed rotor is possible, so it has low cut-in- speed means more energy capture at low wind side.
[33] Pitch - In conventional large wind turbine, due to active pitch control system, the power of wind after rated-wind-speed has spilled. In short power coefficient drastically decreases after rated-wind-speed. To use such spilled wind power, manufacturer increase diameter of rotor. Thereby rated wind speed increases. But due to increase in rotor diameter cut-in-speed also increases, that's why energy not captures from low wind side by such large diameter rotor.
[34] In present invention, high RPM of rotor has no problem. Therefore it has a fixed pitch thereby more of wind flow is utilized.
[35] Efficiency - In present invention vibrations, overloading, tilting, and shock etc. are well controlled. Therefore use of high efficiency fixed pitch rotor is possible e.g. one or two blade rotor. Thereby present wind turbine has high efficiency.
[36] Tower - In conventional wind turbine, the cost of tower is very high nearly
1/4 part of whole system, such costly high strength tower needed to absorb shocks, overload, cyclic stress, Vibration etc.
[37] In present invention, tower is safe from Shocks, Gust, Cyclic stress, Vibration etc. Therefore tower does not get fatigue or suddenly overload that's why it does not need a very high strength tower. Here lattice type tower is preferred which has low cost and broad base means.
[38] Balance of Head - In this invention, when the direction of wind flow suddenly changes, at such result head of turbine changes its direction toward new wind flow; therefore centrifugal force acts on the head and thereby overload on tower. For small scale wind turbine this overload is negligible but for large scale it's very dangerous. To avoid such overload due to centrifugal force, a counter weight has applied to opposite of head. This counter weight Jl avoids the centrifugal force on head thereby tower.
[39] Maintenance - In conventional wind turbine, by using complicated system
(yow control, pitch control, numbers of sensor) there maintenance reach to high, and such maintenance has not possible to handled at local level means for maintenance there required professional technicians, therefore there maintenance cost is also high.
[40] In present invention, by using simple computer less technique and by avoiding complicated systems, such wind turbine take place low maintenance, and by simple technique maintenance cost is also low, because such maintenance handled at local level is possible. [41] Cost - Due to simple technology, low maintenance, low maintenance cost, low cost of lattice tower, simple assembly and absence of complicated system thereby overall cost of present wind turbine is low.
Description of Drawings [42] The present invention will become more fully understood from the detailed description given herein below and accompanying drawing which are given by way of illustration only, and thus are not intended as a definition of the limits of the present invention, and wherein;
Fig IA shows three dimensional view of wind turbine according to the present invention.
Fig IB shows full assembly in front view, side view and top view of the wind turbine according to the present invention. [43] Fig 2 shows close up of three dimensional view of wind turbine head (all components above vertical bearing) according to the present invention.
Fig 3A illustrates internal component of nacelle according to the present invention.
Fig 3B shows Rotor Axle close up of Fig 3 A.
Fig 3C shows axle bearing surrounded by numbers of spring of FIG 3 A.
Fig 4 shows front, side & top views of vane with there clause up of FIG 1. [44] Fig 5 illustrate front, side & top views of Counter Weight with there internal component position such as Generator & Gear Box of the wind turbine according to the present invention.
Fig 6 shows front, side & top views of Horizontal Level Unit the wind turbine according to the present invention.
Fig 7 shows front, side & top views of Main Universal Joint according to the present invention. [45] Fig 8 shows compressive spring & two universal joints attached to both ends of spring according to the present invention.
Fig 9 illustrate power transmission component according to the present invention.
Fig 10 shows front, side & top view of sliding joint and; universal joint which ended on both side of sliding joint according to the present invention. [46] Fig HA illustrate an example of side-to-side coinciding vibration (resonance frequency) condition of wind turbine head according to the present invention. Fig HB illustrate an example of side-to-side vibration at high RPM by means at High wind speed (High wind speed means wind speed more than resonance frequency's wind speed) where amplitude has short with high frequency of wind turbine head according to the present invention.
Fig HC illustrate an example of back & forth (vibration along axle) coinciding vibration with there close up of wind turbine head according to the present invention.
[47] Fig 12 illustrate top view of wind turbine head, shows vibrations of vane and base point (center of vertical bearing) from where head can revolve at 360° according to the present invention.
Fig 13 illustrate some turning phases of wind turbine head, shows when wind direction suddenly flow from cross direction then head of wind turbine turn to opposite direction to line up with new wind flow; here turning points shown by thin circle, according to the present invention.
Components List
[48] 1 - Nacelle
1.1 - Nacelle Frame
1.2 - Axle Bearing
1.3 - Number of Springs Surrounded on Axle Bearing
1.4 - Driver Bevel Gear
[49] 1.5 - Nacelle Back Spring Unit (Bole Joint)
1.6 - Nacelle Back Springs
1.7 - Driven Bevel Gear
1.8 - Supporter for Axle of Driven Bevel Gear [50] 2 - Sub Tower
3 - Main Back Spring
4 - Vane (Tail)
4.1 - Vane Guide Plat
4.2 - Hinge [51] 4.3 - Stopper
4.4 - Shock Absorbing Material (rubber, wood etc)
5 - Side-To-Side Vibration Control Unit for Vane
5.1 - Springs to Control Side-To-Side Vibrations of Vane [52] 5.2 - Spring Supporter
6 - Base of Head 7 _ Supporter
8 - Vertical Roller Bearing
9 - Horizontal Level unit
[53] 9.1 Flange
9.2 Stud
9.3 Nut
9.4 Top End toward Main Vertical Bearing
9.5 Bottom End toward Main Tower
[54] 10 - Tower
11 - Counter Weight
11.1 Generator
11.2 Gear Box
[55] 12 - Power Transmission Unit
12.1 Universal Joint for Power Transmission
12.2 Linear Sliding Joint
[56] 12.3 Power Transmission Connecting Rod
12.4 Small Bevel Gear
13 - Side Spring
14 - Wind Flow Direction pη 15 - Rotor
16 - Rotor Axle
17 - Main Universal Joint
18 - Counter Weight Supporter
Symbol's List
[58] α - Total deflection of Rotor Axle from mean position at side to side Vibration Coinciding αl - Deflection of Sub-Tower from mean position at side to side
Vibration Coinciding
[59] o2 - Deflection of Rotor Axle in Nacelle at Vibration Coinciding col - Deflection Frequency at Vibration Coinciding ω2 - Horizontal Deflection Frequency of Rotor Axle at High Wind
Speed [60] ω3 - Vertical Deflection Frequency of Rotor Axle at High Wind
Speed ω4 - Deflection Frequency of Rotor Axle at Back & Forth action ω5 - Vane Deflection
[61] β - Total deflection of Rotor Axle from mean position at High
Wind Speed (wind speed more than resonance wind speed) βl - Deflection of Sub-Tower from mean position at High Wind
Speed β2 - Deflection of Rotor Axle in Nacelle at High Wind Speed [62] γ - Total deflection at Back & Forth action (Due to Wind Gust) γ 1 - Deflection of Rotor Axle in Nacelle at forth action γ2 - Deflection of Rotor Axle in Nacelle at back action
Best Mode of the Invention
[63] Wind power is non conventional source of energy due to high investment and expensive to maintain in such plants this source is not widely use. Vibration, Gyration, Gust etc are the main reasons of high investment.
[64] Current technologist minimize such problem by maintaining the preciseness of blades, by using high strength structure, by keeping higher diameter of rotor to decrease the RPM and by using computer control system etc.
[65] In this invention vibrations are at any phase are controlled up to there resonance vibrations and also controlled gyroscopic & gust effect. This system avoids the complicated system like Yaw control, Pitch control etc. Therefore the cost and maintenance cost of this system will be least.
[66] In this invention face of rotor 15 line up with wind flow 14 due to Vane 4 &
Axial thrust on rotor 15. Here the condition of rotor axle 16 is maintained in such way that it can vibrate in all phase with there natural vibrations & its vibrations are controlled by compressive spring 3, 13, 13, 1.6 means;
[67] Therefore Vibrations, Overloading, Shocks etc are do not affect to whole system. Thus this system has safe from Gyrations, Fatigue, Shock, Wind gust, Friction etc. Hence, we get mis wind turbine having low cost, low maintenance, low maintenance cost, higher efficiency, low cut-in-speed, high cut out speed etc. Details description explained with the following major parts with there function. [68] Major Farts With There Function
Nacelle 1 - Nacelle 1 comprises rotor axle 16 in such way that can axle 16 vibrate to manage tilting or gyroscopic effect & low scale back impact, wherein axle 16 holding by two bearing 1.2 & such bearing surrounded by numbers of spring 13 to manage tilting effect, one bole joint LS attached to the end of the axel 16, bole joint LS supported by spring 1.6 to manage low scale back impact due to gust or fluctuation of wind flow, at central portion of axle 16 one driver bevel gear 1Λ has attached to transmit power from axle 16 to driven bevel gear 1.7, driven bevel gear 1.7 supported by back side bearing 1.2 with the help of supporting component 1.8, driven bevel gear 1.7 forward power with vibration to universal joint which linked with Linear Sliding Joint. Reference Fig IA, Fig IB, Fig 3A, Fig 3B, Fig 3C, and Fig 9.
[69] Sub Tower 2 - nacelle 1 mounted on sub tower 2; and sub tower 2 means comprises two solid parallel plates which are mounted on base of head 6 with the help of main universal joint 17. Thereby bottom end of sub tower 2 works as base point and top end movement up to some limit at horizontal plain means, mean position maintain by supporting number of spring 3, 13 means. Two parallel plates of sub tower 2 are parallel with wind direction thereby wind flow easily passes through sub tower 2 by means wake or shadow effect are negligible means in other ward cyclic effect negligible here; and such parallel plates give high structural strength as compare to tubular shape tower. Use of sub-tower 2 (two parallel plates) is possible in present invention because main tower 10 & sub tower 2 are not in one line thereby this one is downwind type wind turbine but work like as up-wind type wind turbine. Reference Fig IA, Fig IB, Fig 2.
[70] Main Back Spring 3 - This main back spring 3 used to absorb or control back and forth movements or vibrations or shocks of sub-tower 2 thereby nacelle 1. One end of this spring mounted on Base of Head 6 and another end to back side sub- tower 2 with the help of two universal joints 19. Reference Fig 1, Fig 2, Fig 8.
[71] Vane 4 - Vane 4 attached to back side of Base of Head 6. Vane 4 is flexible up to some limit with help of number of spring 5.7 to avoid there vibration to transmits in whole system. A Guide Plat 4.1 attached at back side of vane 4 to guide vane 4, when wind flow suddenly flow from opposite wind direction.
[72] The present invention is down-wind type wind turbine therefore rotor automatically line up with wind direction. But its need to line up with wind direction at very short time to avoid power loss. In account such problem, vane 4 has given, to line up rotor as early as possible to avoid power loss. Second reason is when wind direction suddenly flow from opposite (back / rear side) direction than rotor spine with opposite direction to avoid such loss vane is provided. The working of this vane at opposite wind flow has shown in Fig 13 with the help of some number of phases, in first phase Vane Guide Plat 4.1 mismatch with wind direction, because Vane Guide Plat 4.1 is one side edge plate, thereby vane turn one side shown in second phase, another phase shows remaining steps regarding line up with cross wind direction. Reference Fig 1, Fig 2, Fig 4, Fig 12, Fig 13.
[73] Base of Head 6 - Main tower 10 & sub tower 2 are not in one line there extension distance covered by using a plat means know as Base of Head 6, means this plat is holding device especially for universal joint 17 (thereby sub tower 2 ), side spring 13 , main back spring 3 & vane 4 etc. Reference Fig IA, Figl.2, Fig 2.
[74] Supporter 7 - This one is supporting plate for Base of Head 6. Reference Fig
1.1, Fig IB, Fig 2.
Main Vertical Bearing 8 - This one is vertical roller bearing thereby head can rotate at 360° and provide strong support. Reference Fig 1, Fig 2.
[75] Horizontal Level unit 9 - This unit helps to set Base of Head 6 horizontal with ground after complete assembly. It has two flange 9.1 attached by three stud 92. Reference Fig 1, Fig 6.
[76] Counter Weight 11 - The heavy weight generator 11.1 and gear box 11.2 are used as counter weight for balancing means, thereby the weights limitations of generator 11.1 and gear box 11.2 increase and flexibility for regular maintenance.
[77] The shape of Counter Weight 11 maintain in such way thereby wind force do not effect to rotor direction which lined with wind direction. Counter Weight 11 has triangular bar with tetrahedron ends thereby minimizes resistance of wind flow from front and both sides, Counter Weight 11 attached to base of Head 6 by using two parallel plates 18 ( parallel to ground also) thereby side to side wind flow do not resist to counter Weight 11 . Reference Fig 1, Fig 2, Fig 5.
[78] Power Transmission Unit 12 - In Power Transmission Unit 12, low speed axle 16 transmit power with all phase vibration, such power provide to gear box 11.2 and/or than generator 11.1 with the help of small universal joints 12.1, connecting roads 12.3 and sliding joints 12.2. Reference Fig 5, Fig 9, Fig 10 [79] Side Spring 13 - This two Side Spring 13 used to absorb or control side-to- side movements or vibrations or shocks of sub-tower 2 thereby nacelle 1. One end of this springs mounted on Base of Head 6 and another end to sub-tower 2 with the help of some universal joints 19. Reference Fig 1, Fig 2, Fig 8.
[80] Rotor 15 - This invention prefer high efficiency rotor, such type of high efficiency rotor has high lift to drag ration thereby rotor spine with high RPM, this invention purpose to use such type of high efficiency rotor with controlling there side effect regarding RPM.
[81] Main Universal Joint 17 - This is the combination of two joints which are perpendicular to each other by means of this joint Nacelle 1 can vibrate or deflect up to some limit at horizontal plane. Reference Fig 2, Fig 7.
Industrial Applicability
[82] The industrial applicability has described with the following topics.
Present wind turbine involve numbers of innovative steps, some step(s) applicable to solve specific problem(s) of conventional wind turbine such as Tower vibration, Rotor racing, Tilting of rotor axle, Shocks by Wind gust, Gyroscopic effect, Material fatigue, Overloading, Friction & RPM limitation etc.
[83] Present wind turbine is applicable for who wish to use high efficiency rotor
(specially large scale one/two blade rotor, concentrating wind turbine etc) with low cost of over all infrastructure with low maintenance.
[84] Present wind turbine is applicable in such wind turbine industry, which going to increase the diameter of rotor day by day, specially to decrease the RPM of rotor thereby high RPM related problem minimizes. By applying present wind turbine, need not to increase diameter of rotor thereby over all infrastructure will reduce.
[85] The maintenance of present wind turbine handle at local level is possible thereby present wind turbine is applicable for such industries which are not capable to provide maintenance service.
[86] By adding some innovative step in conventional wind turbine from present wind turbine, it will make new low cost, low maintenance & high efficiency Wind Turbine.

Claims

Claims
1. A high efficiency horizontal axis wind turbine comprising: a tower divided in two parts as main tower (10) means and sub tower (02) means ; said main tower (10) and sub tower (02) are not in one line and there extensional distance covered by component (06) means ; a nacelle (01) means mounted on sub tower (02); said main tower (10) is stable with ground and sub tower (02) movable with nacelle (01) means sub tower (02) line up with wind direction as nacelle (01); a top of sub tower (02) is flexible, means nacelle (01) can vibrate at horizontal plane means to manage back impact or side to side vibration or horizontal plane overloading effect on nacelle
(01) means; said nacelle (01) comprises rotor axle (16) means, wherein rotor axle (16) is flexible for tilting or vibration means; by mutual action of flexible sub tower (02) and rotor axle (16), thereby any phase vibrations means or resonance vibration or overloading effect of rotor axle (16) do not transmits in whole system, by means vibrations or resonance vibration or overloading effect of rotor axle(16) are control or absorb means.
2. The high efficiency horizontal axis wind turbine of claim 1 wherein vibration control or absorb means, comprises numbers of springs (1.3, 1.6, 03, 13) means use to controls on rotor axle (16) vibrations at any phase, up to there resonance vibrations means, thereby rotor axle(16) vibrations and over loading effect do not transmits in whole system.
3. The high efficiency horizontal axis wind turbine of claim 1 wherein: nacelle (01) comprises rotor axle (16) by supporting bearing(s) (1 ,2) means; and said bearing(s) (1.2) surrounded by numbers of springs (1.3), by means axle (16) can vibrate to manage tilting or gyroscopic effect means, thereby bearings (1.2) & nacelle (01) do not get overload.
4. The high efficiency horizontal axis wind turbine of claim 3 wherein: said nacelle (01) comprises bole joint (1.5) means attached to the end of rotor axel (16); said bole joint (1.5) supported by spring(s) (1.6) means or shock absorbing material to manage low scale back impact oϊ rotor axle (16) on nacelle (01), due to gust or fluctuation in wind flow.
5. The high efficiency horizontal axis wind turbine of claim 3 wherein: a driver bevel gear (1.4) has attached to axle (16) to transmit power via axle (16) to driven bevel gear (1.7) means; said driven bevel gear (1.7) supported by bearing (1.2) with the help of supporting component (1.8) means; said driven bevel gear (1.7) forward power via Universal Joints (12.1) and/or Linear Sliding Joints(12.2) to generator (11.1) or gearbox (11.2).
6. The high efficiency horizontal axis wind turbine of claim 5 wherein linear sliding joint (12.2) comprises two universal joints (12.1) at both ends, thereby power transmits from vibrating main axle (16) to stable generator (11.1) or gearbox (11.2).
7. The high efficiency horizontal axis wind turbine of claim 1 wherein wind flow easily passes from sub tower (02), means sub tower (02) do not produce wake or shadow effect on rotor.
8. The high efficiency horizontal axis wind turbine of claim 7 wherein said sub tower (02) is plate or parallel plates and this plate(s) parallel with wind flow direction thereby wind flow easily passes, thereby cyclic effect minimize and gives high structural strength as compare to round shape.
9. The high efficiency horizontal axis wind turbine of claim I wherein: Component (06) means is a flat plate thereby this plate works as base of head (06); one end side of said component (06) is mounted on of main tower (10) with help of bearing (08) means and other end side to bottom of sub tower (02) with the help of universal joint (17) means.
10. The high efficiency horizontal axis wind turbine of claim 9 wherein bearing (08) is vertical roller bearing means to provide strong support
11. The high efficiency horizontal axis wind turbine of claim 1 wherein vertical mean position of sub tower (02) maintain by supporting spring(s) (03, 13) means or shock absorbing component means.
12. The high efficiency horizontal axis wind turbine of claim 11 wherein springs (03,13), one end of springs (03,13) mounted on Base of Head (06) and another ends to sub tower (02), thereby top side of sub- tower (02) can movements at horizontal plan and bottom side of sub tower (02) is work as base point on base of head (06) thereby sub tower (02) stand at there mean vertical position, thereby horizontal plain vibrations and/or shocks of nacelle (01) are absorb and control means, said spring(s) mounted on Base of Head (06) and sub-tower (02) with the help of universal joints(19) means.
13. The high efficiency horizontal axis wind turbine of claim 9 wherein a Universal Joint (17) mounted on base of head (06) and sub tower (02) mounted on universal joint (17) thereby bottom end of sub tower (02) work as base point means.
14. The high efficiency horizontal axis wind turbine of claim 1 wherein the high efficiency horizontal axis wind turbine is a downwind type.
15. A high efficiency horizontal axis wind turbine comprising: Vane (04) mounted at back end of base of head (06) thereby face of rotor line up with new wind flow direction as early as possible means to reduce loss of energy; said vane (04) is flexible to vibrate means, thereby vane (04) vibrations do not transmits in whole system.
16. The high efficiency horizontal axis wind turbine of claim 15 wherein: vane (04) vibrations control/absorb by using springs) (5.1); and mean position of vane is maintain by supporting springs(s) (5.1).
17. A high efficiency horizontal axis wind turbine comprising guide plate (4.1) means which is attached at back side of vane (04) thereby when wind flows from opposite wind direction, vane (04) turn at one side by guide plate (4.1), thereby head turn to line up with new wind direction.
18. The high efficiency horizontal axis wind turbine of claim 17 wherein guide plate (4.1 ) is a one side edge plate means, thereby this plate turn at one side within stopper (4.3) limit at opposite wind direction.
19. A high efficiency horizontal axis wind turbine comprising horizontal level unit (09) means to set base of head (06) at horizontal to ground level means.
20. The high efficiency horizontal axis wind turbine of claim 19 wherein: horizontal level unit (09) mounted on top of main tower (10); and bearing (08) mounted on horizontal level unit (09).
21. The high efficiency horizontal axis wind turbine of claim 19 wherein horizontal level unit (09) comprises two flanges (9.1) attached by studs (9.2) thereby base of head (06) set at horizontal to ground.
22. A high efficiency horizontal axis wind turbine comprising generators) (11.1) and/or gear box (11.2) are used as counter weight (11) means, for balancing means counter weight (11) comprising generator (11.1) and/or gear box (11.2), thereby the weights limitations of generator (11.1) and gear box (11.2) increase and meet flexibility for regular maintenance of generator (11.1) and/or gear box (11.2) means.
23. The high efficiency horizontal axis wind turbine of claim 22 wherein Counter Weight (11) comprises triangular bar with tetrahedron ends in shape thereby minimizes resistance of wind flow from front and both side's means.
24. The high efficiency horizontal axis wind turbine of claim 22 wherein Counter Weight (11) attached to front of base of Head (06) by supporting component (18) means.
25. The high efficiency horizontal axis wind turbine of claim 24 wherein component (18) is plate(s) parallel to ground, thereby side to side wind flow do not resist to counter Weight (11).
PCT/IN2009/000172 2008-11-24 2009-03-13 Horizontal axis wind turbine WO2010018590A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IN2465/MUM/2008 2008-11-24
IN2465MU2008 2008-11-24

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Cited By (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101287140B1 (en) 2011-11-02 2013-07-17 윤상억 Vibration decrease appartus for wind generator
WO2014125114A1 (en) * 2013-02-18 2014-08-21 Peter Lutz Wind turbine comprising a gimbal-mounted tower
CN111219290A (en) * 2020-03-08 2020-06-02 北京工业大学 Double-wind-wheel self-rotating wind power generation tower capable of collecting multiple energy sources and reducing vibration and energy consumption

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2916878A1 (en) * 1979-04-26 1980-11-06 Ernst Rogge Wind turbine with pivoted rotating mast - has turbine wheel and flow guidance vanes at end of mast angled at 45 degrees to horizontal
CN87206813U (en) * 1987-04-24 1988-07-20 刘心民 Electric generator driven by weak wind
US7004724B2 (en) * 2003-02-03 2006-02-28 General Electric Company Method and apparatus for wind turbine rotor load control based on shaft radial displacement
CN101220797A (en) * 2007-01-10 2008-07-16 通用电气公司 Method and device for forming wind turbine machine

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE2916878A1 (en) * 1979-04-26 1980-11-06 Ernst Rogge Wind turbine with pivoted rotating mast - has turbine wheel and flow guidance vanes at end of mast angled at 45 degrees to horizontal
CN87206813U (en) * 1987-04-24 1988-07-20 刘心民 Electric generator driven by weak wind
US7004724B2 (en) * 2003-02-03 2006-02-28 General Electric Company Method and apparatus for wind turbine rotor load control based on shaft radial displacement
CN101220797A (en) * 2007-01-10 2008-07-16 通用电气公司 Method and device for forming wind turbine machine

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
KR101287140B1 (en) 2011-11-02 2013-07-17 윤상억 Vibration decrease appartus for wind generator
WO2014125114A1 (en) * 2013-02-18 2014-08-21 Peter Lutz Wind turbine comprising a gimbal-mounted tower
CN111219290A (en) * 2020-03-08 2020-06-02 北京工业大学 Double-wind-wheel self-rotating wind power generation tower capable of collecting multiple energy sources and reducing vibration and energy consumption
CN111219290B (en) * 2020-03-08 2021-04-30 北京工业大学 Double-wind-wheel self-rotating wind power generation tower capable of collecting multiple energy sources and reducing vibration and energy consumption

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