Patent Application
20100135796
The present disclosure generally relates to wind turbines, and, more particularly, to monitoring the condition of joints in a split rotor blade for a wind turbine.
Wind turbines have received increased attention as an environmentally safe and relatively inexpensive alternative energy source. With this growing interest, considerable efforts have been made to develop wind turbines that are reliable and efficient.
Generally, a wind turbine includes a rotor comprised of a hub and a plurality of blades mounted on the hub. The rotor is coupled to a generator through a gearbox. The generator is mounted within a housing or nacelle, which is positioned on top of a tubular tower. Utility grade wind turbines (i.e., wind turbines designed to provide electrical power to a utility grid) can have large rotors (e.g., thirty or more meters in diameter). Blades of such a rotor transform wind energy into a rotational torque or force that drives a generator. The rotor is supported by the tower through a bearing that includes a fixed portion coupled to a rotatable portion.
Current and future technologies in wind turbines are looking for higher rotor diameters to capture more energy. The larger wind turbines can have rotor blade assemblies that are larger than 90 meters in diameter. Large commercial wind turbines are capable of generating between one and one-half megawatts to five megawatts of power. The size, shape and weight of rotor blades are factors that contribute to the energy efficiencies of wind turbines. As rotor blade size increases, extra attention needs to be given to the structural integrity of the rotor blades.
Rotor blades of longer length, due to their length and larger sizes, are generally associated with manufacturing and transport difficulties. Split wind turbine rotor blades, i.e. rotor blades comprised of two or more joinable members, have been developed to address the difficulties associated with longer rotor blades.
The split blade concept is important in longer rotor blades due to transport and other structural implications. Split wind turbine rotor blades will include a joint between each of the joinable members of the rotor blade. However, joints of any kind are critical in rotor blades due to the usage of directional sensitive materials like fiber-reinforced composites. Monitoring the structural critical parameters of the joint is advantageous to detect early indications of joint failures, avoid catastrophic failure of the rotor blade as well as the wind turbine in the event of a joint failure, and to improve present and future joint methodologies.
Accordingly, it would be desirable to provide a system that addresses at least some of the problems identified above.
As described herein, the exemplary embodiments overcome one or more of the above or other disadvantages known in the art.
One aspect of the exemplary embodiments relates to a split wind turbine rotor blade. In one embodiment, the split wind turbine rotor blade includes a first rotor blade member, a second rotor blade member, a joint between the first rotor blade member and the second rotor blade member, and a joint monitoring device disposed in an area of the joint for monitoring a structural integrity of the joint.
Another aspect of the exemplary embodiments relates to a system for monitoring a joint of a split wind turbine blade. The system includes a joint monitoring device disposed on the split wind turbine blade for monitoring a structural parameter of the joint, and a controller configured to receive monitored parameter data from the joint monitoring device and to determine whether the monitored parameter data meets or exceeds a predetermined threshold value for the monitored structural parameter.
A further aspect of the exemplary embodiments relates to a method of monitoring joint efficiency of a joint in a split wind turbine blade. In one embodiment, the method includes receiving parameter data from a joint monitoring device, the joint monitoring device monitoring a structural parameter of the joint, determining if the received parameter data exceeds a threshold level, and generating a joint efficiency control signal if the received parameter data exceeds the threshold level.
These and other aspects and advantages of the exemplary embodiments will become apparent from the following detailed description considered in conjunction with the accompanying drawings. It is to be understood, however, that the drawings are designed solely for purposes of illustration and not as a definition of the limits of the invention, for which reference should be made to the appended claims. Moreover, the drawings are not necessarily drawn to scale and unless otherwise indicated, they are merely intended to conceptually illustrate the structures and procedures described herein. In addition, any suitable size, shape or type of elements or materials could be used.
In the drawings:
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The wind turbine 100 includes a wind turbine control system 530, an example of which is generally shown in
As shown in
The aspects of the disclosed embodiments provide for monitoring the structural critical parameters of the joint 220. In one embodiment, a condition based monitoring system for monitoring wind turbine split rotor blade joint efficiency is provided. Sensors and/or measuring equipment are used to monitor certain structural parameters of the joint 220. Referring to
The joint monitoring sensor(s) 404 is generally configured to monitor structural parameters of the joint 220. These parameters can include, but are not limited to, deflection, strain and vibration of the joint(s) or the areas near the joint 220. In the exemplary embodiments described herein, the sensor(s) 404 is placed internally to the blade 108, near or at the location of the joint 220, in order to monitor structural critical parameters related to the joint 220.
In one embodiment, the sensor(s) 404 is a deflection sensor 406. The deflection sensor(s) 406 is generally configured to sense and monitor the deflection levels at the joint 220 of the split blade 108. The deflection sensor(s) 406 can include any suitable deflection monitoring devices, such as, for example, potentiometers, tilt sensors, position indicators and wire-actuated sensors.
In
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In the exemplary embodiment illustrated in
The aspects of the disclosed embodiments provide for monitoring the efficiency of the joint 220 using one or more joint monitoring sensors 404. The sensor(s) will provide data with respect to the structural conditions or parameters of the joint 220. The monitored parameters can be used to minimize or prevent damage to the blade 108 or wind turbine 100. In one embodiment, the parameters measured by the sensor 404 are provided to a control system 530, such as that shown in
The condition based monitoring system of the disclosed embodiments is configured to detect a joint 220 failure condition in advance, and take action that will prevent catastrophic damage to the respective blade 108 and wind turbine 100. In one embodiment, detecting a joint failure condition can include comparing the measured parameter data from each sensor 404 to a predetermined threshold limit for the measured parameter. If the predetermined value is met or exceeded, this can be indicative of a failure condition. In this situation, the particular turbine can be stopped, or other suitable action taken, such as for example an alarm or notification. The threshold limit of the measured parameter(s) can be set and determined in any suitable manner, such as by, for example, blade test data or allowable limits of the materials and joint as determined during blade design.
In one embodiment, the controller 520 receives the measured parameter data from the sensor 404. The controller 520 can be configured to interpret the data. If the data indicates a joint failure condition, for example, by comparing the measured parameter data to predetermined values, the controller 520 can be configured to generate a signal that will cause the respective wind turbine 100 to shut down. In one embodiment, the controller 520 sends the suitable signal to the control system 530. The control system 530 initiates action to shut down the respective turbine 100. Alternatively, the controller 520 can be configured to send a shutdown signal directly to the respective turbine 100.
Referring to
The measured parameter data as indicated by the sensor 404 is compared at 604 to a threshold level. In one embodiment, if the threshold level is met or exceeded, the turbine is identified at 606 for immediate action. This can include, for example, identifying the particular turbine on a user interface of the control system 530, initiating an automatic shutdown and/or or sounding an alarm. If the threshold level is not met, the turbine 500 can be left to its continued operation and/or its status at 608. The operational status can be shown by a display. For example, in a wind farm control system, there can be a display indicator for each wind turbine 500. The operational status of each turbine can be identified on a display of the control system 530. In one embodiment, the display can be color-coded so as to be able to easily identify or distinguish turbines for which an alert or shutdown is indicated or initiated. In alternate embodiments, any suitable method of distinguishing turbines can be used.
The disclosed embodiments may also include software and computer programs incorporating the process steps and instructions described above. In one embodiment, the programs incorporating the process described herein can be stored on or in a computer program product and executed in one or more computers.
As shown, a computer system or controller 702 may be linked to another computer system or controller 704, such that the computers 702 and 704 are capable of sending information to each other and receiving information from each other. In one embodiment, the computer system 702 could include a server computer or controller adapted to communicate with a network 706. Alternatively, where only one computer system is used, such as the computer system 704, it will be configured to communicate with and interact with the network 706. Computer systems 704 and 702, such as the controller(s) 520 and control system 530 of
The computer systems 702 and 704 are generally adapted to utilize program storage devices embodying machine-readable program source code, which is adapted to cause the computer systems 702 and 704 to perform the method steps and processes disclosed herein. The program storage devices incorporating aspects of the disclosed embodiments may be devised, made and used as a component of a machine utilizing optics, magnetic properties and/or electronics to perform the procedures and methods disclosed herein. In alternate embodiments, the program storage devices may include magnetic media, such as a diskette, disk, memory stick or computer hard drive, which is readable and executable by a computer. In other alternate embodiments, the program storage devices could include optical disks, read-only-memory (“ROM”) floppy disks and semiconductor materials and chips.
The computer systems 702 and 704 may also include a microprocessor for executing stored programs. The computer system 704 may include a data storage or memory device 708 on its program storage device for the storage of information and data. The computer program or software incorporating the processes and method steps incorporating aspects of the disclosed embodiments may be stored in one or more computer systems 702 and 704 on an otherwise conventional program storage device. In one embodiment, the computer systems 702 and 704 may include a user interface 710, and/or a display interface 712, such as a graphical user interface, from which aspects of the disclosed embodiments can be presented and/or accessed. The user interface 710 and the display interface 712, which in one embodiment can comprise a single interface, can be adapted to allow the input of queries and commands to the systems, as well as present the results of the analysis of the sensor data, as described with reference to
The aspects of the disclosed embodiments provide for monitoring the condition of a structural joint in a split rotor blade for a wind turbine. Sensors and measuring equipment are used to monitor certain parameters of the joint. A comparison can be made between the monitored parameter(s) and threshold limit(s) stored in the system. When a value for a monitored parameter(s) meets or exceeds the threshold limit, an indication or other suitable signal can be generated. Based on this information, the particular turbine can be stopped or other suitable action initiated to prevent damage, or further damage, to the wind turbine. In this manner, joint defects in the rotor blade can be detected in advance and catastrophic damage to the blade and wind turbine prevented.
Thus, while there have been shown, described and pointed out, fundamental novel features of the invention as applied to the exemplary embodiments thereof, it will be understood that various omissions and substitutions and changes in the form and details of devices illustrated, and in their operation, may be made by those skilled in the art without departing from the spirit of the invention. Moreover, it is expressly intended that all combinations of those elements and/or method steps, which perform substantially the same function in substantially the same way to achieve the same results, are within the scope of the invention. Moreover, it should be recognized that structures and/or elements and/or method steps shown and/or described in connection with any disclosed form or embodiment of the invention may be incorporated in any other disclosed or described or suggested form or embodiment as a general matter of design choice. It is the intention, therefore, to be limited only as indicated by the scope of the claims appended hereto.
