Patent Application
20130174509
The present subject matter relates generally to wind turbines and, more particularly, to a platform assembly within the tower of a wind turbine.
Platforms in wind turbine towers provide operators safe access to areas of a wind turbine that may require servicing, maintenance and inspection. For example, the platforms are typically located adjacent to the tower flange bolts for safe and easy inspection of the flange bolts. Typically, a number of service platforms are located at different heights in the turbine tower and are fixed by welding or with bolts to the tower wall.
A conventional type of platform includes a metal plate, typically a checker plate, which is supported by a number of steel beams fixed to the tower walls. Steel beams are heavy, have to be lifted with a crane when mounting the platform in the tower, and are thus generally difficult to install. Further, a significant number of bosses, clip plates, and the like, are necessary to mount the plate to the beams, which is both time and cost intensive.
The conventional platforms are also tailored to a specific tower diameter, and must be redesigned whenever the tower shell diameter or wall thickness changes. This is due primarily to maintaining a required maximum space of about one-inch between the circumference of the plate and the tower wall.
A further conventional design (referred to as a “bent plate”) includes a self-supporting platform formed from a metal sheet. The round platform may have multiple positions where the sheet has been cold formed such that a double layered I-section is formed which protrudes along the width of the platform. This vertical sheet section of the platform may provide some degree of stability, however the cold forming process is technically demanding and cost intensive.
In light of the above, it is desirable to have a platform for a wind turbine tower which is relatively easy to produce and assemble within the tower, and is versatile so as to be used at different diameter sections of the same or different wind turbine towers.
Aspects and advantages of the invention will be set forth in part in the following description, or may be obvious from the description, or may be learned through practice of the invention.
In accordance with aspects of the invention, a modular platform assembly is provided for a wind turbine tower. In a particular embodiment, the platform assembly includes a plurality of individual, multi-sided plate members, with each of the plate members connected to at least one other plate member along a common side. At least certain ones of the plate members have an outboard side that collectively define a circumferential section of the platform assembly. In one embodiment, all of the plate members have an outboard side and contribute to the circumference of the plate assembly. The connected common sides of the plate members define a structural support grid that connects to an interior wall within a wind turbine tower at a plurality of circumferential positions for supporting the platform assembly relative to the tower.
In a particular embodiment of the platform assembly, the plate members are each formed from a single unitary metal plate, with the metal plates having down-turned flanges along the common sides that are connected together to define the structural support grid. The flanges may, for example, be bolted together along the common sides.
In one embodiment, one of the plate members is common to all of the other plate members and thus shares a common side with each remaining plate member. This common plate member may also have an outboard side that defines a circumferential section of the platform assembly. Alternatively, the common plate member may be an interior plate member that is completely surrounded by the other remaining plate members.
The outboard sides of the plate members that define the circumference of the platform assembly may include integral toe rails defined by up-turned flanges along straight lengths of the outboard sides.
It should be appreciated that any one or combination of the plate members may have any manner of access opening or port defined therein, for example to accommodate a lift or ladder, cable runs, and so forth. The plate members may include up-turned flanges that define a toe rail around the access openings.
The platform assembly may further include a plurality of brackets configured for mounting onto the tower wall at the plurality of circumferential support positions, with the brackets defining a seat for the structural support grid. The brackets may be provided in varying radial lengths (or a sufficiently long radial length) so that the same size platform assembly is mountable to varying diameter sections of the wind turbine tower wall.
The present invention also encompasses any manner of wind turbine having a plurality of the present platform assemblies configured at different heights within the tower. In a particular embodiment, at least two of the platform assemblies within the tower have the same circumferential dimension and are mounted at respective locations within the tower having different diameters. The platform assemblies are supported by brackets having a sufficient radial length so as to accommodate for different radial distances between the platform assemblies and the interior wall of said tower.
These and other features, aspects and advantages of the present invention will become better understood with reference to the following description and appended claims. The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention.
A full and enabling disclosure of the present invention, including the best mode thereof, directed to one of ordinary skill in the art, is set forth in the specification, which makes reference to the appended figures, in which:
Reference now will be made in detail to embodiments of the invention, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the invention, not limitation of the invention. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present invention without departing from the scope or spirit of the invention. For instance, features illustrated or described as part of one embodiment can be used with another embodiment to yield a still further embodiment. Thus, it is intended that the present invention covers such modifications and variations as come within the scope of the appended claims and their equivalents.
Referring now to the drawings,
The tower 12 is a tubular structure that may be constructed from individual stacked segments that are bolted together at flange locations, as in well known in the art. These segments may be formed from any number or combination of suitable materials, including metal and concrete. Typically, a respective platform assembly 20 is disposed at different heights within the tower 12, for example at the flange bolt locations. These platform assemblies serve various functions, including a rest stop for personnel that climb the tower 12 to access the nacelle 14, inspection and maintenance platforms, equipment support platforms, and so forth. The number of platform assemblies 20 and their respective heights within the tower 12 depends on the individual configuration of the wind turbine 10. The number of platform assemblies is typically from 2 to 6, more typically from 3 to 5. In a non-limiting example, platforms are provided, for example, at 4.4 m height (4.2 m platform diameter), at 21 m (4.2 m diameter), at 46 m (3.3 m diameter), at 68 m (2.7 m diameter) and at 75 m (2.5 m diameter).
An embodiment of a platform assembly 20 is depicted in
As particularly seen in
The individual plate members 22 may be variously configured. For example, the plate members 22 may be formed from a single unitary metal plate, with the plates collectively defining a generally uninterrupted upper surface 24 of the platform assembly 20. The metal plates may have down-turned flanges 34 (
The down-turned flanges 34 are desirably bent into their orientation relative to the upper surface 24 so as to avoid welding steps. Alternatively, the flanges 34 may be separately attached, for example by welding, bolts, or other suitable means.
The size, shape, and configuration of the plate members may vary widely within the scope and spirit of the invention. For example, referring to
In an alternate embodiment depicted in
Referring to the figures in general, a toe rail 40 is defined around the circumference of the platform assembly 20. In one embodiment, this toe rail 40 may consist of one or more separate components that are attached to the plate members 22. In the illustrated embodiments, as particularly illustrated in
The plate members 22 may be connected together by various means. In the illustrated embodiments, the down-turned flanges 34 along the common sides 30 are bolted together with bolts 48, which may also be considered as components of the continuous support grid 44. In an alternate embodiment, the flanges 34 may be welded together.
Any manner and configuration of access openings 52 may be provided in the plate members 22 for various purposes. For example, an interior access opening 52 may be provided to accommodate a lift, while another is provide in the outboard side 28 of one or more of the plate members 22 for a ladder that extends along the interior was of the tower. Additional access openings 52 may be provided along the outboard sides 28 for cable and bus runs.
Referring to
As can be appreciated from
It should be readily appreciated that the present invention also encompasses any manner of wind turbine 10 (
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 include 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 languages of the claims.
