System and method for harvesting energy of wind turbine during off-grid state

Abstract

The invention relates to a system and method for harvesting energy of a wind turbine during an off-grid state. Specifically, a method for harvesting energy from one or more internal energy sources of a wind turbine of a wind farm during an off-grid state includes harvesting energy from one or more internal energy sources located local to the wind turbine during the off-grid state. The off-grid state is characterized in that the wind turbines are mechanically and electrically installed at the wind farm but not yet connected to the grid. The method also includes storing at least a portion of the energy in one or more energy storage devices located locally to the wind turbine or the wind farm during the off-grid state. Further, the method includes periodically powering one or more electrical power systems for idle operation or maintenance operation of the wind turbine using the energy during the off-grid state.

Description

TECHNICAL FIELD

[0001] The present disclosure relates generally to wind turbine power generation systems, and more particularly to systems and methods for sourcing energy of a wind turbine required during idling maintenance of the wind turbine during off-grid state. BACKGROUND

[0002] Wind is considered one of the cleanest and most environmentally friendly energy sources currently available, and wind turbines have gained increasing interest in this regard. A modern wind turbine typically includes a tower fixed at its upper end to a foundation, a nacelle housed within the tower, a generator and a gearbox housed within the nacelle, and a rotor having a rotatable hub with one or more rotor blades configured with the nacelle. The rotor blades capture kinetic energy of wind using known airfoil principles. The rotor blades transmit the kinetic energy in the form of rotational energy to a shaft that is coupled to the gearbox, or directly to the generator if no gearbox is used. The generator then converts the mechanical energy into electrical energy that can be deployed to a utility grid. A modern wind turbine also includes a turbine controller for controlling its operation.

[0003] A plurality of wind turbines can also be arranged at a common geographical location, referred to as a wind farm (or wind park). The wind farm can be connected to an electrical grid for its power supply. However, at the time of installation, there is a time frame during which the wind turbines are mechanically and electrically complete without availability of grid interconnection. This state of the wind turbine / wind farm is generally referred to as "off-grid state". The time frame of off-grid state can be days, weeks, months or even years depending on many factors specific to the location of the wind farm, such as grid availability, grid code requirements, incentives, tax credits, etc. In such a case, the wind turbines of the wind farm need to perform various idling maintenance jobs while off-grid and in an upright storage state (i.e. installed but not operational). However, the source of power for handling such jobs is not available.

[0004] In view of the foregoing, the present disclosure is directed to systems and methods for sourcing energy of a wind turbine during off-grid state, such that the sourced energy can be used for handling various idling maintenance jobs. SUMMARY

[0005] Aspects and advantages of the disclosure will be set forth in part in the following description, or can become apparent from the description, or can be learned through practice of the

[0006] In one aspect, the present disclosure is directed to a method for harvesting energy from one or more internal energy sources of a wind turbine of a wind farm during an off-grid state. The off-grid state is characterized by the wind turbine being mechanically and electrically installed at the wind farm, but not yet connected to a power grid. The method includes collecting energy from one or more internal energy sources located locally to the wind turbine during the off-grid state. The method also includes storing at least a portion of the energy in one or more energy storage devices located locally to the wind turbine or the wind farm during the off-grid state. Further, the method includes periodically powering one or more electrical power systems for idling operation or maintenance jobs of the wind turbine using the energy during the off-grid state.

[0007] In another aspect, the present disclosure is directed to a wind turbine configured to harvest energy during an off-grid state. The off-grid state is characterized by the wind turbine being mechanically and electrically installed on-site, but not yet connected to a power grid. The wind turbine includes a tower and a rotor mounted on top of the tower. The rotor includes a rotatable hub having at least one rotor blade mounted thereto. The wind turbine also includes one or more internal energy sources, one or more energy storage devices, and a turbine controller in communication with the one or more internal energy sources and the one or more energy storage devices. The turbine controller is configured to perform a plurality of operations including, but not limited to: collecting energy from one or more internal energy sources located locally to the wind turbine during the off-grid state; storing at least a portion of the energy in the one or more energy storage devices during the off-grid state; and periodically powering one or more electrical power systems for idling operation or maintenance jobs of the wind turbine using the energy during the off-grid state.

[0008] These and other features, aspects, and advantages of the present disclosure 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 present disclosure and serve to explain the principles of the present disclosure. BRIEF DESCRIPTION OF DRAWINGS

[0009] The complete disclosure of the present disclosure, including its best mode, directed to those of ordinary skill in the art, is set forth in the specification and attached drawings, of which: Figure 1 shows a perspective view of an embodiment of a wind turbine according to the present disclosure; Figure 2 shows a simplified internal view of an embodiment of a nacelle according to the present disclosure; Figure 3 shows a schematic view of an embodiment of a main controller of a wind turbine according to the present disclosure; Figure 4 shows a schematic view of an embodiment of a wind farm having a plurality of wind turbines according to the present disclosure; Figure 5a flowchart illustrating an embodiment of a method for harvesting energy of a wind turbine during an off-grid state according to the present disclosure; Figure 6 a schematic block diagram illustrating an embodiment of a method for harvesting energy of a wind turbine during an off-grid state according to the present disclosure; Figure 7 a partial perspective view illustrating an embodiment of a nacelle of a wind turbine according to the present disclosure, in particular illustrating solar panels mounted at an angle on top of the nacelle for harvesting energy during an off-grid state of the wind turbine; and Figure 8 a perspective view illustrating another embodiment of a nacelle of a wind turbine according to the present disclosure, in particular illustrating solar panels mounted in a geodesic triangular pyramid arrangement on top of the nacelle for harvesting energy during an off-grid state of the wind turbine.

[0010] Reference signs that are repeated in the description and the drawings have the same or similar meaning. DETAILED DESCRIPTION

[0011] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are illustrated in the drawings. Each example is provided by way of explanation of the present disclosure, not limitation of the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations can be made in the present disclosure without departing from the scope or spirit of the present disclosure. 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 disclosure cover modifications and variations of this present disclosure provided they come within the scope of the appended claims and their equivalents.

[0012] As used herein throughout the description and claims, approximate language is used to modify any quantitative representation that can tolerably vary without resulting in a change in the basic function to which it is related. Accordingly, a value modified by terms or phrases such as "about," "approximately," and "substantially" is not limited to the specified precise value. In at least some instances, the approximate language can correspond to the precision of an instrument used to measure the value, or the precision of a method or machine used to construct or manufacture the component and / or system. For example, the approximate language can refer to within a 10% margin.

[0013] In general, this disclosure relates to systems and methods for harvesting energy from wind turbines during off-grid operation. Wind turbine installation can occur where the machine is mechanically and electrically complete without grid interconnection available. In such cases, an electrical power source is required to support idling maintenance operations of the wind turbine while it is off-grid and in a vertically stored state. Therefore, in this disclosure, energy from multiple sources can be harvested at the wind turbine and stored locally to support the wind turbine's electrical power needs. In some embodiments, kinetic energy from rotor rotation, tower vibration, and / or solar radiation provides energy for local capture, storage, and use. Energy harvesting methods for kinetic or radiative sources can be combined with storage in a rechargeable system to provide readily available local power for idling maintenance of the wind turbine when external power sources (i.e., the grid, temporary generators) are unavailable.

[0014] Now refer to the attached diagram, Figure 1 A perspective view of an embodiment of a wind turbine 10 according to the present disclosure is shown. As shown, the wind turbine 10 generally includes a tower 12 extending from a support surface 14, a nacelle 16 mounted on the tower 12, and a rotor 18 coupled to the nacelle 16. The rotor 18 includes a rotatable hub 20 and at least one rotor blade 22 coupled to and extending outward from the hub 20. For example, in the illustrated embodiment, the rotor 18 may include three rotor blades 22. However, in alternative embodiments, the rotor 18 may include more or fewer than three rotor blades 22. Each rotor blade 22 may be spaced around the hub 20 to facilitate the rotation of the rotor 18 so that kinetic energy from the wind can be converted into usable mechanical energy, and further into electrical energy. For example, the hub 20 may be rotatably coupled to a generator 24 located within the nacelle 16. Figure 2 This allows for the generation of electrical energy during normal operation of the wind turbine 10.

[0015] The wind turbine 10 may also include a turbine controller 26 centrally located within the nacelle 16. For example, as shown, the turbine controller 26 is located in the top cabinet 48. Figure 2 However, in other embodiments, the turbine controller 26 may be located within any other component of the wind turbine 10, or at a location external to the wind turbine 10. Further, the turbine controller 26 may be communicatively coupled to any number of components of the wind turbine 10 or distributed to control the operation of such components and / or perform control actions. Therefore, the turbine controller 26 may include a computer or other suitable processing unit. Accordingly, in several embodiments, the turbine controller 26 may include suitable computer-readable instructions that, when implemented, configure the turbine controller 26 to perform various functions, such as receiving, transmitting, and / or performing wind turbine control action signals, receiving and analyzing sensor signals, and generating message signals.

[0016] By transmitting and executing wind turbine control action signals, turbine controller 26 can be generally configured to control various operating modes (e.g., start-up or shutdown sequences) and / or components of wind turbine 10. For example, controller 26 can be configured to control the yaw direction of nacelle 16 about yaw axis 43 to position rotor blades 22 relative to wind direction 66, thereby controlling the power output generated by wind turbine 10. For example, as described in more detail herein, turbine controller 26 can be configured to transmit control action signals / commands to one or more yaw drive mechanisms 40 of wind turbine 10 ( Figure 2 This allows the nacelle 16 to rotate about the yaw axis 43. The turbine controller 26, which may be part of the turbine control circuit or completely independent, may also operate auxiliary systems in the wind turbine 10, including pumps and motors, to periodically circulate the mechanical and electrical systems during off-grid exposure.

[0017] Now for reference Figure 2 , shown in Figure 1 The diagram shows a simplified internal view of an embodiment of the nacelle 16 of the wind turbine 10. As shown, a generator 24 may be disposed within the nacelle 16. Typically, the generator 24 may be coupled to a rotor 18 to generate electrical power based on the rotational energy generated by the rotor 18 during operation of the wind turbine 10. For example, as shown in the illustrated embodiment, the rotor 18 may include a rotor shaft 34 coupled to a hub 20 to rotate therewith. The rotor shaft 34 may then be rotatably coupled to a generator shaft 36 of the generator 24 via a gearbox 38. As generally understood, the rotor shaft 34 may provide a low-speed, high-torque input to the gearbox 38 in response to rotation of the rotor blades 22 and the hub 20. The rotor shaft 34 typically includes a flange 35 that facilitates mechanical engagement of the rotor shaft 34 with the hub 20. The gearbox 38, opposite the hub 20, may then be configured to convert the low-speed, high-torque input into a high-speed, low-torque output to drive the generator shaft 36 and thus the generator 24.

[0018] The nacelle 16 may include a yaw drive mechanism 40 configured to change the angle of the nacelle 16 relative to the wind (e.g., by engaging a yaw bearing 42 of the wind turbine 10, which is disposed between the nacelle 16 and the tower 12 of the wind turbine 10). Further, each yaw drive mechanism 40 may include a yaw drive motor 44 (e.g., any suitable electric or hydraulic motor), a yaw drive gearbox 45, and a yaw drive pinion 46. In such embodiments, the yaw drive motor 44 may be coupled to the yaw drive gearbox 45 such that the yaw drive motor 44 applies a mechanical force to the yaw drive gearbox 45. Similarly, the yaw drive gearbox 45 may be coupled to the yaw drive pinion 46 to rotate therewith. The yaw drive pinion 46 may then be rotatably engaged with the yaw bearing 42 connected between the tower 12 and the nacelle 16 such that rotation of the yaw drive pinion 46 causes rotation of the yaw bearing 42. Therefore, in such embodiments, the rotation of the yaw drive motor 44 drives the yaw drive gearbox 45 and the yaw drive pinion 46, thereby causing the yaw bearing 42 and the nacelle 16 to rotate about the yaw axis 43.

[0019] Similarly, the wind turbine 10 may include a pitch system 32 having one or more pitch adjustment mechanisms 33 communicatively coupled to the turbine controller 26, wherein each pitch adjustment mechanism 33 is configured to rotate a pitch bearing 47, and thus rotate individual rotor blades 22 about a pitch axis 28. The pitch adjustment mechanisms 33 described herein may have any suitable arrangement. Additionally, the pitch adjustment mechanism 33 may include a pitch motor, a pitch gearbox, and a pitch pinion. Furthermore, as shown, the pitch system 32 may also include a pitch system storage medium 39. In such embodiments, the pitch system storage medium 39 may include a battery, a supercapacitor, and / or any other suitable storage medium.

[0020] In addition, the wind turbine 10 may also include one or more sensors 52 for monitoring various wind conditions of the wind turbine 10, and one or more sensors 37 for sensing the load conditions acting on the wind turbine. For example, such as Figure 2 As shown, wind direction, wind speed, or any other suitable wind conditions near wind turbine 10 can be measured, such as by using a suitable weather sensor 52. Suitable weather sensors 52 include, for example, light detection and ranging (“LIDAR”) devices, sound detection and ranging (“SODAR”) devices, anemometers, wind vanes, barometers, radar devices (e.g., Doppler radar devices), meteorological (Met) mast systems, or any other field or remote sensing device or system that can provide weather, pressure, or wind information now known or hereafter developed in the art.

[0021] Now for reference Figure 3A block diagram of an embodiment of a turbine controller 26 according to the present disclosure is shown. As shown, the turbine controller 26 may include a computer or other suitable processing unit that may include suitable computer-readable instructions that, when implemented, configure the controller 26 to perform various functions, such as receiving, transmitting, and / or performing wind turbine control action signals. More specifically, as shown, a block diagram of an embodiment of an example aspect of the present disclosure that may include suitable components within the turbine controller 26 is shown. As shown, the turbine controller 26 may include one or more processors 58 and associated memory devices 60 configured to perform various computer-implemented functions (e.g., performing the methods, steps, calculations, etc., disclosed herein).

[0022] As used herein, the term "processor" refers not only to integrated circuits known in the art as included in a computer, but also to controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application-specific integrated circuits (such as relay devices), and other programmable circuits. Furthermore, memory device 60 may generally include memory elements, including but not limited to computer-readable media (e.g., random access memory (RAM)), computer-readable non-volatile media (e.g., flash memory), floppy disks, read-only optical discs (CD-ROMs), magneto-optical discs (MODs), digital multifunction discs (DVDs), physical configuration settings with DIP switches or rotary switches, and / or other suitable memory elements.

[0023] Such a memory device 60 may be generally configured to store suitable computer-readable instructions that, when executed by the processor 58, configure the turbine controller 26 to perform various functions as described herein. Furthermore, the turbine controller 26 may also include a communication interface 62 to facilitate communication between the turbine controller 26 and various components of the wind turbine 10. In embodiments, the communication interface 62 may support a combination of open-loop or closed-loop feedback between sensors or other communication modules. The interface may include one or more circuits, terminals, pins, contacts, conductors, or other components for sending and receiving control action signals. Additionally, the turbine controller 26 may include a sensor interface 64 (e.g., one or more analog-to-digital converters) to allow signals transmitted from sensors to be converted into signals that can be understood and processed by the processor 58.

[0024] Now for reference Figure 4The wind turbine 10 described herein may be part of a wind farm 50. As shown, the wind farm 50 may include a plurality of wind turbines 53 (including the wind turbine 10 described above) and a total farm-level controller 56. For example, as shown in the illustrated embodiment, the wind farm 50 includes twelve wind turbines (including wind turbine 10). However, in other embodiments, the wind farm 50 may include any other number of wind turbines, such as fewer than twelve or more than twelve wind turbines. In embodiments, the turbine controllers of the plurality of wind turbines 53 are communicatively connected to the farm-level controller 56, for example, via a wired connection, such as by connecting turbine controller 26 via a suitable communication link 54 (e.g., a suitable cable). Alternatively, the turbine controllers may be communicatively connected to the farm-level controller 56 via a wireless connection, such as by using any suitable wireless communication protocol known in the art. In a further embodiment, the farm-level controller 56 is configured to send control signals to and receive control signals from each wind turbine 53.

[0025] Now for reference Figure 5 This diagram illustrates a flowchart of an embodiment of a method 100 for obtaining energy from one or more internal energy sources of a wind turbine in a wind farm during off-grid operation, according to this disclosure. During normal operation, the energy storage devices (such as batteries) of the wind turbine 10 are charged by drawing power from the grid or generated by the wind turbine 10 when the grid is available. During off-grid operation, these power sources are unavailable. Therefore, during off-grid operation, this disclosure utilizes internal energy sources to power the energy storage devices for use when needed. As used herein, “internal energy sources” generally refers to those sources that do not use the grid, such as off-grid energy, charge / discharge regulators, and / or energy storage media, as opposed to grid-based energy.

[0026] Additionally, as used in the text, the off-grid status is characterized by the wind turbines being mechanically and electrically installed at the wind farm, but not yet connected to the power grid. Overall, the text references... Figures 1-4 Method 100 is described with wind turbine 10 and wind farm 50. However, it should be recognized that the disclosed method 100 can be implemented using any wind turbine with any other suitable configuration. Furthermore, although... Figure 5 For illustrative and discussion purposes, steps performed in a particular order are depicted, but the methods discussed herein are not limited to any particular order or arrangement. Those skilled in the art will recognize, using the disclosure provided herein, that the individual steps of the methods disclosed herein may be omitted, rearranged, combined, and / or modified in various ways without departing from the scope of this disclosure.

[0027] As shown at (102), method 100 includes harvesting energy from one or more internal energy sources located locally at the wind turbine during off-grid status. For example, as shown in Figure 6 As shown in the figure, in the embodiments, the internal energy 200 may include kinetic energy 202 and / or radiant energy 204.

[0028] In such embodiments, kinetic energy 202 may represent the kinetic energy from the rotation of the rotor 18 of the wind turbine 10, the kinetic energy from the vibration of the tower 12 of the wind turbine 10, and / or any other suitable kinetic energy source of the wind turbine 10. Therefore, in one embodiment, method 100 may include connecting the rotor 18 of the wind turbine 10 to a permanent magnet electric motor, which is connected to a high-speed flywheel on the drivetrain of the wind turbine 10. Thus, the rotation of the rotor 18 drives the permanent magnet electric motor to generate kinetic energy. In another embodiment, method 100 may include connecting the tower 12 of the wind turbine 10 to a linear electromagnetic generator, wherein the vibration of the tower 12 drives the linear electromagnetic generator to generate kinetic energy.

[0029] Furthermore, in an embodiment, the radiant energy 204 may include solar radiation from one or more solar panels 206 mounted on the wind turbine 10. For example, as in Figure 7 As shown, the wind turbine 10 may include one or more solar panels 206 mounted on top of the nacelle 16, specifically showing that the solar panels 206 may be angled upwards or downwards. In some embodiments, such solar panels 206 may be mounted in a fixed position or may be controlled via an actuator (not shown) to change the angle of one or more of the solar panels 206 relative to the nacelle 16 and thus relative to the sun. Furthermore, as in... Figure 8 The diagram shows a perspective view of another embodiment of the nacelle 16 of the wind turbine 10 according to this disclosure, specifically showing solar panels 206 mounted on top of the nacelle 16 in a geodesic triangular pyramid arrangement for harvesting energy during the off-grid operation of the wind turbine 10. As used herein, a geodesic triangular pyramid generally refers to an arrangement in which smaller triangular sub-components are joined together to form a larger triangular four-sided pyramid. In such embodiments, the geodesic triangular pyramid may also be referred to as a pyramid dome, wherein the triangular arrangement of the solar panels 206 is mounted in a manner that allows continuous exposure to sunlight regardless of the wind turbine heading or the angle of inclination of the sunlight relative to the incident solar panels.

[0030] Additionally, in this embodiment, the radiant energy sources are connected in a manner that limits the open-circuit voltage for the overall output of the energy system through parallel and series connections between the various energy sources. Specifically, the electrical connections of the solar panel 206 are implemented to limit voltage potential and electrical hazards. For example, the solar panel can be electrically connected in a manner that limits the open-circuit voltage for the entire system through a combination of parallel and series connections.

[0031] Return to reference Figure 5 As shown at (104), method 100 may optionally include switching the mode of one or more energy storage devices 208 from a discharge-only mode to a bidirectional discharge-internal charge mode as part of one or more off-grid conditions. In embodiments, for example, energy storage device 208 may be an existing pitch system storage medium (e.g., pitch system storage medium 39 described herein), an existing power converter storage medium in the power converter of wind turbine 10, an auxiliary storage system in wind turbine 10, or an existing field-level energy storage medium at wind farm 50 (such as storage medium in field-level controller 56). Thus, in embodiments where the energy storage device is an existing pitch system storage medium, since the existing pitch system storage medium operates in a discharge-only mode during normal operation of wind turbine 10, method 100 may include switching the mode of the existing pitch system storage medium from a discharge-only mode to a bidirectional discharge-charge mode before storing at least a portion of the energy locally at wind turbine 10.

[0032] As shown at (106), method 100 also includes storing at least a portion of the energy in one or more energy storage devices 208 located locally at the wind turbine 10 or wind farm 50 during off-grid operation. Therefore, as shown in Figure 6 As shown, the energy collected from multiple energy sources can be stored, for example, on the wind turbine 10 and / or locally at the wind farm 50.

[0033] Return to reference Figure 5 As shown at (108), method 100 includes periodically supplying energy to one or more electrical power systems used for idling operation or maintenance work 210 of a wind turbine during off-grid conditions. For example, in an embodiment, as shown in Figure 6 As shown, the idling operation or maintenance work 210 of the wind turbine 10 during off-grid status may include the periodic operation of the motor system, programmable logic controller (PLC) system, auxiliary lighting or lifting device.

[0034] Further aspects of this disclosure are provided by the subject matter of the following provisions: A method for harvesting energy from one or more internal energy sources of a wind turbine at a wind farm during an off-grid state, characterized in that the wind turbine is mechanically and electrically installed at the wind farm but not connected to the power grid, the method comprising: harvesting energy from one or more internal energy sources located at the wind turbine location during the off-grid state; storing at least a portion of the energy in one or more energy storage devices located at the wind turbine or at the wind farm location during the off-grid state; and periodically supplying power to one or more electrical power systems for idling operation or maintenance work of the wind turbine during the off-grid state.

[0035] The method described under any of the foregoing provisions further includes switching the mode of one or more energy storage devices from a discharge-only mode to a bidirectional discharge-internal charging mode as part of one or more off-grid conditions before storing at least a portion of the energy locally at the wind turbine.

[0036] According to the method described in any of the foregoing clauses, one or more energy storage devices include at least one of existing pitch system storage media, existing power converter storage media, auxiliary storage systems in wind turbines, or existing field-level energy storage media at wind farms.

[0037] According to any of the foregoing provisions, the method wherein one or more energy storage devices include an existing pitch system storage medium that operates in a discharge-only mode during normal operation of the wind turbine.

[0038] The method described under any of the foregoing provisions further includes switching the mode of the existing pitch system storage medium from a discharge-only mode to a bidirectional discharge-internal charging mode as part of one or more off-grid conditions before storing at least a portion of the energy locally at the wind turbine.

[0039] The method according to any of the foregoing clauses, wherein the existing pitch system storage medium includes at least one of a battery or a supercapacitor.

[0040] The method according to any of the foregoing provisions, wherein one or more internal energy sources include at least one of kinetic energy or radiative energy.

[0041] The method according to any of the foregoing clauses, wherein the kinetic energy source includes at least one of the kinetic energy from the rotation of the rotor of the wind turbine or the kinetic energy from the vibration of the tower of the wind turbine.

[0042] The method according to any of the foregoing provisions further includes connecting the rotor of the wind turbine to a permanent magnet electric motor, which is connected to a high-speed flywheel on the wind turbine's drivetrain, wherein the rotation of the rotor drives the permanent magnet electric motor.

[0043] The method according to any of the foregoing provisions further includes connecting the tower of the wind turbine to a linear electromagnetic generator, wherein vibrations of the wind turbine tower drive the linear electromagnetic generator.

[0044] The method according to any of the foregoing provisions, wherein the radiative energy includes solar radiation from one or more solar panels mounted on a wind turbine.

[0045] The method according to any of the foregoing clauses, wherein the idling operation or maintenance work of the wind turbine during off-grid status includes at least one of the periodic operation of the motor system, programmable logic controller (PLC) system, auxiliary lighting or lifting device.

[0046] A wind turbine configured to harvest energy during an off-grid state, characterized in that the wind turbine is mechanically and electrically installed on-site but not connected to the power grid, the wind turbine comprising: a tower; a rotor mounted on top of the tower, the rotor including a rotatable hub having at least one rotor blade mounted thereto; one or more internal energy sources; one or more energy storage devices; and a turbine controller in communication with the one or more internal energy sources and the one or more energy storage devices, the turbine controller being configured to perform a plurality of operations including: harvesting energy from the one or more internal energy sources located locally at the wind turbine during the off-grid state; storing at least a portion of the energy in the one or more energy storage devices during the off-grid state; and periodically supplying power to one or more electrical power systems for idling operations or maintenance work of the wind turbine during the off-grid state.

[0047] According to any of the foregoing provisions, the wind turbine, wherein one or more energy storage devices include at least one of existing pitch system storage media, existing power converter storage media, auxiliary storage systems in wind turbines, or existing field-level energy storage media.

[0048] According to any of the foregoing provisions, the wind turbine includes one or more energy storage devices comprising an existing pitch system storage medium, which includes at least one of a battery or a supercapacitor, and which operates in a discharge-only mode during normal operation of the wind turbine.

[0049] According to any of the foregoing provisions, the plurality of operations further include, before storing at least a portion of the energy locally at the wind turbine, switching the mode of the existing pitch system storage medium from a specified discharge-only mode to a bidirectional discharge-internal charging mode as part of one or more off-grid conditions.

[0050] According to any of the foregoing provisions, the wind turbine, wherein one or more internal energy sources include at least one of kinetic energy or radiative energy, the kinetic energy including at least one of the kinetic energy from the rotation of the rotor of the wind turbine or the kinetic energy from the vibration of the tower of the wind turbine, and the radiative energy including solar radiation from one or more solar panels mounted on the wind turbine.

[0051] According to any of the foregoing provisions, the wind turbine further includes connecting the rotor of the wind turbine to a permanent magnet electric motor, which is connected to a high-speed flywheel in the wind turbine's drivetrain, wherein the rotation of the rotor drives the permanent magnet electric motor.

[0052] The wind turbine according to any of the foregoing provisions, wherein the plurality of operations further includes connecting the tower of the wind turbine to a linear electromagnetic generator, wherein vibrations of the wind turbine tower drive the linear electromagnetic generator.

[0053] According to any of the foregoing provisions, the idling operation or maintenance work of the wind turbine during off-grid status includes at least one of the periodic operation of the motor system, programmable logic controller (PLC) system, auxiliary lighting or lifting device.

[0054] This written description uses examples to disclose this disclosure (including the best mode) and also enables those skilled in the art to practice this disclosure, including making and using any apparatus or system and performing any incorporated methods. The patentable scope of this disclosure is defined by the claims and may include other examples that would 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 are not different from the literal language of the claims, or if they include equivalent structural elements that are not substantially different from the literal language of the claims.

Claims

1. A method for harvesting energy from one or more internal energy sources of a wind turbine at a wind farm during an off-grid state, the off-grid state being characterized by the wind turbine being mechanically and electrically installed at the wind farm but not yet connected to a power grid, the method comprising: collecting energy from the one or more internal energy sources located locally at the wind turbine during the off-grid state; storing at least a portion of the energy in one or more energy storage devices located locally at the wind turbine or the wind farm during the off-grid state; and periodically powering one or more electrical power systems for idling operation or maintenance jobs of the wind turbine using the energy during the off-grid state.

2. The method of claim 1, further comprising switching a mode of the one or more energy storage devices from a discharge-only mode to a bidirectional discharge-internal charging mode prior to storing the at least a portion of the energy locally at the wind turbine as part of one or more off-grid conditions. the one or more energy storage devices comprise at least one of an existing pitch system storage medium, an existing power converter storage medium, an auxiliary storage system in the wind turbine, or an existing farm-level energy storage medium at the wind farm.

3. The method of claim 1, wherein, the one or more energy storage devices comprise the existing pitch system storage medium, the existing pitch system storage medium operating in the discharge-only mode during a normal state of the wind turbine.

4. The method of claim 3, wherein, 5. The method of claim 4, further comprising switching a mode of the existing pitch system storage medium from the discharge-only mode to a bidirectional discharge-internal charging mode prior to storing the at least a portion of the energy locally at the wind turbine as part of one or more off-grid conditions. the existing pitch system storage medium comprises at least one of a battery or a supercapacitor.

6. The method of claim 4, wherein, the one or more internal energy sources comprise at least one of kinetic energy or radiant energy.

7. The method of claim 1, wherein, the kinetic energy comprises at least one of kinetic energy from rotation of a rotor of the wind turbine or kinetic energy from vibrations of a tower of the wind turbine.

8. The method of claim 7, wherein, the rotation of the rotor drives the permanent magnet electric motor.

9. The method of claim 8, further comprising connecting the rotor of the wind turbine to a permanent magnet electric motor connected to a high speed flywheel on the drive train of the wind turbine, wherein, the vibrations of the tower of the wind turbine drive the linear electromagnetic generator.

10. The method of claim 8, further comprising connecting the tower of the wind turbine to a linear electromagnetic generator, wherein, ​

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