The present disclosure relates generally to wind turbines, and more particularly to a system and method for uptower machining of a wind turbine to accommodate a load control system.
Wind power is considered one of the cleanest, most environmentally friendly energy sources presently available, and wind turbines have gained increased attention in this regard. Referring to
The blades 16 convert motive force of the wind into rotational mechanical energy via the shaft 22 and gearbox 30 to generate electricity with the generator 15. Modern wind turbines 10 may also include a controller 33 centralized within the nacelle 14. Alternatively, the controller 33 may be located within any other component of the wind turbine 10 or at a location outside the wind turbine.
Many modern wind turbines employ various load control systems to reduce loads on the rotor blades and/or other wind turbine components to allow increased power production while maintaining a 20-year design life. For example, various wind turbines employ General Electric Company's Advanced Load Controls (ALC) system as described in U.S. Pat. No. 7,822,560 entitled “Methods and Apparatuses for Wind Turbine Fatigue Load Measurement and Assessment” filed Dec. 23, 2004 to reduce loads of various wind turbine components. The ALC system of the '560 patent measures stresses acting on the components via a plurality of sensors and then implements a corresponding control action when necessary, such as adjusting blade pitch.
One embodiment of a load control system for use in the wind turbine 10 is illustrated in
To accommodate the ALC system, modern wind turbines employ a specially designed rotor lock plate 21 such that the system 40 can obtain sensor measurements from the main shaft flange 20. Conventional wind turbines, however, must be retro-fitted to accommodate the ALC system because conventional rotor lock plates 21 do not have comparable tolerances to the main shaft flange 20. As such, current installation methods for conventional wind turbines require disassembling and removing the rotor and corresponding rotor lock plate. Additionally, the rotor lock plate must be replaced with one of the specially designed rotor lock plates to accommodate the ALC system. As such, installation associated with retro-fitting existing wind turbines with ALC systems can be time-consuming and costly.
Thus, an improved system and method for retro-fitting an existing wind turbine with an ALC system would be desired in the art. For example, a system and method that provided uptower machining to accommodate the ALC system would be advantageous.
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 one aspect, a method for uptower machining of a wind turbine to accommodate a load control system is disclosed. The load control system includes a plurality of load control components. The method includes designating a first machining location on a rotor lock plate of the wind turbine; mounting a machining device within the wind turbine proximate to the first machining location; machining the first machining location on the rotor lock plate via the machining device; and, installing the load control system within the wind turbine such that at least one of the load control components is installed proximate to the first machining location.
In another aspect, a machining device for uptower machining of a wind turbine to accommodate a load control system is disclosed. The machining device comprises a mountable body configured to mount within the wind turbine proximate to a first machining location on a rotor lock plate of the wind turbine; a drilling tool configured for drilling the rotor lock plate; and, a milling tool configured for milling the rotor lock plate. The milling tool may include a track follower configured to move along a surface of the main shaft. Further, the track follower may include a spring connection.
In yet another aspect, a system for uptower machining of a wind turbine to accommodate a load control system is disclosed. The system includes a machining device configured to perform a variety of machining operations, a monitoring system, and a controller. The machining device may include any of the features described herein. For example, the machining device may include a mountable body configured to mount within the wind turbine proximate to a first machining location on a rotor lock plate of the wind turbine. The monitoring system may include one or more sensors configured to monitor the machining device. The controller is communicatively coupled to the machining device and the monitoring system. Further, the controller is configured to control operation of the machining device and the monitoring system.
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.
Generally, the present disclosure is directed to a system and method for uptower machining of a wind turbine to accommodate a load control system configured to reduce loads acting on various wind turbine components. For example, in one embodiment, the load control system is an Advanced Load Controls (ALC) system by General Electric Company. In one embodiment, the present disclosure includes a machining device having a mountable body, a securing device, a drilling tool, and a milling tool. As such, the machining device is capable of performing a variety of machining operations to the rotor lock plate of the wind turbine, including, but not limited to, drilling, boring, grinding, milling, and/or similar.
The mountable body is configured to mount to any suitable location within the wind turbine, such as a main bearing housing so as to be proximate to a machining location on the rotor lock plate. The securing device is configured to secure the machining device to the main bearing housing and/or the rotor lock plate. By temporarily securing the machining device to the rotor lock plate during particular machining operations, the drilling tool is capable of drilling one or more circular holes in the rotor lock plate that are not elongated due to backlash in the drivetrain during operation of the wind turbine. By securing the machining device to the main bearing housing during machining operations, the milling tool provides more precise and accurate machining of the rotor lock plate. As such, the machining device is capable of machining the rotor lock plate during operation of the wind turbine (i.e. while the wind turbine is moving) such that the rotor lock plate emulates the main shaft flange of the rotor.
The system may also include a torque device for rotating the rotor before, during, and/or after various machining operations. As such, the rotor lock plate may be rotated such that the machining device can remain stationary but may still machine one or more desired machining locations. In addition, the present system may include a monitoring system for monitoring machining operations and a controller for controlling such operations. As such, the rotor lock plate may be machined until predetermined tolerances are achieved so as to emulate the main shaft flange, at which time the monitoring system can send a signal to the controller to stop machining operations.
The present system and method includes many advantages not present in the prior art. For example, the present machining device and process may advantageously provide for accurate and efficient machining of the rotor lock plate during operation of the wind turbine such that any suitable load control system can be retro-fitted therein. More specifically, the present system and method provides uptower machining during normal wind turbine operation, yet is capable of ensuring that the machining locations on the rotor lock plate are accurately designated and have the appropriate tolerances so as to emulate the main shaft flange. As such, when the load control system (e.g. the ALC system) is retro-fitted within conventional wind turbines, a plurality of sensors (e.g. proximity sensors) can obtain accurate measurements from the rotor lock plate instead of the main shaft flange. As such, machining the wind turbine uptower provides substantial cost savings and reduced installation time.
Referring now to the drawings,
Referring particularly to
The machining device 50 may also include a drilling or boring tool 52 configured for drilling the machining location 29 on the rotor lock plate 21. For example, in one embodiment, the drilling tool 52 is configured to drill a hole in the rotor lock plate 21. As such, the drilling took 52 may be a drill press, a drill bit, an end mill, or any suitable drilling tool for machining a hole. Further, the machining device 50 may include a milling tool 53, such as a mill press, configured for milling the machining location 29 (
The machining device 50 may also include one or more securing devices 56 configured to secure the machining device 50 within the wind turbine 10. The securing device(s) 56 may include any suitable clamp, vice device, flanges, or other suitable securing device, and combinations thereof. For example, in the illustrated embodiment of
In a further embodiment, the machining device 50 may also include a designation device 60 configured to designate the desired machining location 29 on the rotor lock plate 21. The designation device 60 may, in some embodiments, be a center punch. Alternatively, the designation device 60 may be any suitable rod, light locating device or laser locating device (such as a precision laser beam), or other suitable tool for designating a machining location 29 as described herein. Additionally or alternatively, a separate device may be utilized to mark the desired machining location 29. For example, a marker, such as a pen or pencil, a separate punching device, or another suitable marking device, may be utilized to mark the desired machining location 29.
In still another embodiment, the machining device 50 may also include a torque device 61 configured to rotate the rotor 18, which also rotates the rotor lock plate 21. In one embodiment, for example, the torque device 61 may include a motor and pinion gear that is mounted to the high speed brake disc bracket (located near the generator 30). As such, the pinion gear meshes with the high speed brake disc and the motor drives rotation of the drivetrain. More specifically, the motor may be coupled to the torque device 61 such that the motor imparts mechanical force to the torque device 61. Similarly, the torque device 61 may be coupled to the pinion which may, in turn, be in rotational engagement with the gearbox 30 such that rotation of the pinion causes rotation of the rotor 18. Thus, in such embodiments, rotation of the motor drives the pinion and the gearbox 30, thereby rotating the rotor 18 and the rotor lock plate 21. It should be understood that the motor may be any suitable electric, hydraulic, or pneumatic motor known in the art.
As mentioned, the machining device 50 is configured to perform a plurality of machining operations to the wind turbine 10 so as to accommodate the load control system, such as ALC system 40. For example, in one embodiment, the machining device 50 may be configured to machine the rotor lock plate in one or more locations. As such, the machining device 50 is first secured to a fixed location in the wind turbine 10. For example, as shown in the illustrated embodiment of
After the machining device 50 is secured, the machining device 50 is configured to machine a first machining location 29. For example, in the embodiment shown in
In one embodiment, e.g. wherein the rotor lock plate 21 has two seams, the removable flanges 58 can be temporarily removed from the rotor lock plate 21 after the first hole 62 is drilled, filled, and cured (if necessary). As such, the torque device 61 may rotate the rotor 18 (and corresponding rotor lock plate 21) such that the second seam 26 is rotated 180 degrees into the machining position 29. The machining device 50 is then configured to repeat the machining process for the second seam 26 by drilling a hole through the second seam 26 and filling the hole 62 with an appropriate filler 64 as described above in regards to the first seam 25. It should be understood that machining the one or more seams 25, 26 may not be necessary in wind turbines having rotor lock plates made of a single plate (e.g. a rotor lock plate without seams) instead of multiple plate segments.
In further embodiments, and if necessary, the removable flanges 58 can be uninstalled from the rotor lock plate 21 before further machining is implemented, as shown in
Referring now to
More specifically, the controller 72 may include one or more processor(s) 74 and associated memory device(s) 76 configured to perform a variety of computer-implemented functions (e.g., performing the methods, steps, calculations and the like and storing relevant data as disclosed herein). The monitoring system 78 may also include a communications module 82 to facilitate communications between the controller 72 and the various components of the wind turbine 10. Further, the communications module 82 may include a sensor interface 80 (e.g., one or more analog-to-digital converters) to permit signals transmitted from the sensors 84, 86, 88 to be converted into signals that can be understood and processed by the processors 74. It should be appreciated that the sensors 84, 86, 88 may be communicatively coupled to the communications module 82 using any suitable means. For example, as shown in
Referring now to
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.