Patent Application
20110133588
The subject matter described herein relates generally to wind turbines and, more particularly, to a life extension kit for a wind turbine generator support frame.
Wind turbines have been receiving increased attention for being environmentally safe and relatively inexpensive alternative energy sources. With the growing interest in alternative energy sources, considerable efforts have been made to develop wind turbines that are reliable, efficient, and cost effective.
Some known wind turbines include a generator support frame including a main frame or a “bedplate” and a generator support frame or a “rear frame” portion that is cantilevered from the bedplate. Known generator support frames may be subjected to stresses including dynamic loading that may cause fatigue cracking and/or failure.
In one aspect, a method is provided for installing a modular life extension kit onto a support frame for a wind turbine generator. The support frame includes a support member coupled to a support cross-member. The support member has a first length, and the support cross-member has a second length. The method includes providing a plurality of plates configured to be coupled to the support frame. At least a first plate of the plurality of plates has a first side extending at least five percent of the first length and a second side extending at least five percent of the second length. The first side is aligned with the support member and the second side with the support cross-member. The first plate is coupled to the support frame along the first side and the second side.
In another aspect, a modular life extension kit is provided for use with a support frame for a wind turbine generator. The support frame includes at least a support member coupled to a support cross-member. The support member has a first length and the support cross-member has a second length. The modular life extension kit includes a plurality of plates configured to be coupled to the support frame. At least a first plate of the plurality of plates has a first side configured to be coupled to the support member and a second side configured to be coupled to the support cross-member. The first side extends at least five percent of the first length and the second side extends at least five percent of the second length.
In yet another aspect, a support system is provided for a wind turbine generator. The support system includes a generator support frame and a modular life extension kit. The generator support frame includes at least a support member and a support cross-member coupled to the support member. The support member has a first length and the support cross-member has a second length. The modular life extension kit includes a plurality of plates configured to be coupled to the generator support frame. At least a first plate of the plurality of plates has a first side configured to be coupled to the support member and a second side configured to be coupled to the support cross-member. The first side extends at least five percent of the first length and the second side extends at least five percent of the second length.
The methods and systems described herein relate to a life extension kit that is configured to extend a useful life of a wind turbine generator support frame. The life extension kit is configured to provide structural support to the wind turbine generator support frame. Moreover, the life extension kit is configured to provide an alternate load path for the wind turbine generator support frame, which reduces stress at weld joints and thus reduces occurrence of “crack” indication and/or propagation.
In the exemplary embodiment, wind turbine 10 includes a tower 12 that extends from a supporting surface 14, a nacelle 16 mounted on tower 12, and a rotor 18 that is coupled to nacelle 16. Tower 12 is fabricated from any suitable material. In the exemplary embodiment, tower 12 is fabricated from rolled plate steel. Tower 12 has any suitable height that enables wind turbine 10 to function as described herein.
Rotor 18 includes a hub 20 rotatable about an axis of rotation 22. Rotor 18 is positionable at any suitable angle with respect to a direction 24 of the wind to harness wind energy. In the exemplary embodiment, as wind strikes rotor blades 26 from direction 24, rotor 18 is rotated about axis of rotation 22.
Rotor 18 includes any suitable number of rotor blades 26 coupled to and extending outwardly from hub 20. In the exemplary embodiment, rotor 18 includes three rotor blades 26. As used herein, the term “blade” is intended to be representative of any device that provides a reactive force when in motion relative to a surrounding fluid. Rotor blades 26 are spaced about hub 20 to facilitate rotating rotor 18 to enable kinetic energy to be transferred from the wind into usable mechanical energy, and subsequently, electrical energy. Loads induced to rotor blades 26 are transferred to hub 20.
A control system 28 is communicatively coupled to a plurality of the components of wind turbine 10 for generally monitoring and controlling operation of wind turbine 10 and/or some or all of the components thereof. Control system 28 may be used to monitor and control the overall system including, without limitation, pitch and speed regulation, high-speed shaft and yaw brake application, yaw and pump motor application, fault monitoring and/or acoustic emission regulation, for example.
Each support member 56 has a first length 62, and each support cross-member 58 has a second length 63. In the exemplary embodiment, first length 62 is about 2800 mm, and second length 63 is about 2220 mm. In the exemplary embodiment, rear frame portion 50 has a frame area defined by first length 62 and second length 63. In the exemplary embodiment, the frame area includes at least one opening 60 defined between the inner edges of each support member 56. More specifically, in the exemplary embodiment, a first opening 60 is defined by first and second support members 56 and 57 and first cross-member 58, and a second opening 61 is defined by first and second support members 56 and 57 and first and second support cross-members 58 and 59. Openings 60 and 61 are described generally herein as opening 60.
A modular life extension kit 300 is coupled to at least a portion of generator support frame 46 and, more specifically, to rear frame portion 50. Life extension kit 300 includes a suitable number of plates 301 that are configured to extend across at least a portion of opening 60 defined by support members 56 and support cross-members 58. In the exemplary embodiment, life extension kit 300 extends across at least twenty percent of opening 60. More specifically, life extension kit 300 extends across at least thirty percent of opening 60. Even more specifically, life extension kit 300 extends across at least forty percent of opening 60.
In the exemplary embodiment, life extension kit 300 includes a first plate 302, a second plate 304, a third plate 306, a fourth plate 308, a fifth plate 310, and a sixth plate 312. In the exemplary embodiment, first, second, third, and fourth plates 302, 304, 306, and 308 are configured to extend across at least a portion of second opening 61, and fifth and sixth plates 310 and 312 are configured to extend across at least a portion of first opening 60. Plates 302, 304, 306, 308, 310, and 312 are described generally herein as plate 301.
Each plate 301 has a suitable configuration to fit a corresponding portion of rear frame portion 50 and/or other components housed within nacelle 16. In the exemplary embodiment, each of first plate 302, second plate 304, fifth plate 310, and sixth plate 312 has a shape that is generally triangular, and each of third plate 306 and fourth plate 308 has a shape that is generally rectangular.
Each plate 301 has a first side 314 coupled to a first portion of rear frame portion 50 and a second side 316 coupled to a second portion of rear frame portion 50. In the exemplary embodiment, first side 314 has a length 328 and second side 316 has a width 329 described in further detail below.
In the exemplary embodiment, first side 314 is substantially perpendicular to second side 316. As such, a corner of plate 301 formed by first side 314 and second side 316 has an angle of about 90 degrees. In the exemplary embodiment, first side 314 is configured to be coupled to support member 56 and second side 316 is configured to be coupled to support cross-member 58. More specifically, in the exemplary embodiment, first sides 314 of first, second, and sixth plates 302, 304, and 312 are configured to be coupled to first support member 56, and first sides 314 of third, fourth, and fifth plates 306, 308, and 310 are configured to be coupled to second support member 57. Moreover, in the exemplary embodiment, second sides 316 of first, fourth, fifth, and sixth plates 302, 308, 310, and 312 are configured to be coupled to first support cross-member 58, and second sides 316 of second and third plates 304 and 306 are configured to be coupled to second support cross-member 59.
Each plate 301 has at least one of a first cutout 318 and a second cutout 320. In the exemplary embodiment, first cutout 318 is positioned at a first corner, and second cutout 320 is positioned at a second corner that is opposite the first corner. More specifically, in the exemplary embodiment, first cutout 318 is positioned at the corner of plate 301 formed by first side 314 and second side 316.
First cutout 318 has any suitable shape and size to enable visual inspection of a portion of generator support frame 46. For example, first cutout 318 may be configured to enable joint 54 to be visually inspected. In the exemplary embodiment, first plate 302, second plate 304, fourth plate 308, fifth plate 310, and sixth plate 312 each has first cutout 318 having a shape that is generally rectangular and third plate 306 has first cutout 318 having a shape that is generally triangular.
Second cutout 320 has any suitable shape and size to receive at least a portion of a component coupled to electrical generator 34 and/or at least a portion of electrical generator 34. For example, second cutout 320 may be configured to receive at least a portion of another component housed within nacelle 16. In the exemplary embodiment, first plate 302, second plate 304, fifth plate 310, and sixth plate 312 each has second cutout 320 having a shape that is substantially triangular. More specifically, in the exemplary embodiment, fifth plate 310 and sixth plate 312 each has second cutout 320 configured to receive at least a portion of electrical generator 34.
In the exemplary embodiment, a plurality of openings 322 are defined through plate 301 along first side 314 and along second side 316. Each opening 322 is configured to receive a suitable coupling mechanism to couple plate 301 to rear frame portion 50. In the exemplary embodiment, each opening 322 is configured to receive a bolt. Alternatively, plate 301 may be coupled to generator support frame 46 using any suitable coupling mechanism including, without limitation, a clamp and/or a weld.
In the exemplary embodiment, plates 301 have a surface area that extends across a portion of the frame area to enable a person to walk on life extension kit 300. In the exemplary embodiment, at least a portion of at least one plate 301 includes a non-slip surface 324. More specifically, at least one plate 301 includes a top surface including a non-slip surface 324 to enable a person to safely walk on life extension kit 300. Moreover, in the exemplary embodiment, the generally rectangular shape of third plate 306 and fourth plate 308 serves as a walkway that enables a person to walk on life extension kit 300.
Referring now to
Each plate 301 has a suitable weight. In the exemplary embodiment, plate 301 has a weight up to about 250 pounds (lbs). More specifically, in the exemplary embodiment, plate 301 has a weight between about 70 lbs. to about 175 lbs.
Each plate 301 is fabricated from a suitable material. In the exemplary embodiment, plate 301 is fabricated from at least one of a stainless steel, a carbon steel coated with zinc spray coating, and a carbon steel with hot dip galvanized coating.
In the exemplary embodiment, a plurality of openings (not shown) are suitably provided in rear frame portion 50 to enable life extension kit 300 to be coupled to rear frame portion 50. More specifically, in the exemplary embodiment, each opening is drilled in support member 56 and/or support cross-member 58 to be suitably positioned with respect to openings 322 of plate 301.
In the exemplary embodiment, plates 300 are provided 402. Each plate 300 is configured to be coupled to generator support frame 46. In the exemplary embodiment, plate 301 is positioned 404 such that first side 314 is aligned with support member 56 and second side 316 is aligned with support cross-member 58. More specifically, in the exemplary embodiment, plate 301 is aligned such that openings 322 are suitably positioned with respect to a cooperating opening provided in support member 56 and/or support cross-member 58. Additionally, in the exemplary embodiment, plate 301 is oriented such that first cutout 318 enables visual inspection of a portion of generator support frame 46, second cutout 320 enables receiving at least one of at least a portion of electric generator 34 and at least a portion of a component coupled to electric generator 34, and/or non-slip surface 324 faces upward.
In the exemplary embodiment, plate 301 is coupled 406 to rear frame portion 50 using a suitable coupling mechanism, such as a bolt. More specifically, in the exemplary embodiment, each opening 322 and each corresponding opening provided in rear frame portion 50 receives the suitable coupling mechanism to couple 406 plate 301 to rear frame portion 50. In the exemplary embodiment, plate 301 is coupled 406 to rear frame portion 50 using a bolted joint connection. Alternatively, plate 301 may be coupled 406 to rear frame portion 50 using welds and/or clamps.
Life extension kit 300 extends a useful life of generator support frame 46 by providing additional support to generator support frame 46 and providing an alternative load path for generator support frame 46. Life extension kit 300 reduces vibration induced dynamic stress at joints 54 of generator support frame 46. As such, life extension kit 300 provides a robust structural load-path that reduces frame sensitivity to weld defect, indication, and/or crack propagation for generator support frame 46. Moreover, life extension kit 300 may alter a natural frequency and/or a mode shape of generator support frame 46, thereby increasing a system level vibration margin for generator support frame 46.
Although the methods described and/or illustrated herein are described and/or illustrated herein with respect to a life extension kit for a wind turbine generator support frame for a wind turbine generator, the methods described and/or illustrated herein are not limited to wind turbine generators. Rather, the methods described and/or illustrated are applicable to repairing any suitable apparatus or component.
Exemplary embodiments of the life extension kit and methods for installing the life extension kit onto the generator support frame for the wind turbine generator are described above in detail. The methods and systems are not limited to the specific embodiments described herein, but rather, steps of the methods and components of the systems may be utilized independently and separately from other steps and/or components described herein. For example, the methods and systems described herein may have other industrial and/or consumer applications and are not limited to practice with wind turbines as described herein. Rather, one or more embodiments may be implemented and utilized in connection with other industries.
As used herein, an element or step recited in the singular and proceeded with the word “a” or “an” should be understood as not excluding plural said elements or steps, unless such exclusion is explicitly stated. Further, references to “one embodiment” are not intended to be interpreted as excluding the existence of additional embodiments that also incorporate the recited features. Moreover, unless explicitly stated to the contrary, embodiments “comprising,” “including,” or “having” an element or a plurality of elements having a particular property may include additional such elements not having that property.
This written description uses examples to disclose the invention, including the best mode, and also to enable any person skilled in the art to practice the invention, including making and using any devices or systems and performing any incorporated methods. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements with insubstantial differences from the literal language of the claims.
