System and method for dynamic management of a wind turbine providing reactive power

Abstract

Systems and methods for controlling a wind turbine that provides reactive power are provided. Specifically, a method for controlling a power system may be provided, the power system including a controller and one or more wind turbines electrically connected to a power grid via an interconnection point. The method may include receiving a signal from a sensor, the signal being associated with the wind turbine. The method may also include determining a wind turbine operating under low wind or no wind operating conditions based at least in part on one or more of the sensor signals. The method may also include determining a reactive power capability of a wind turbine operating under low wind or no wind conditions, and generating a control signal based at least in part on the reactive power capability of the wind turbine. The method may also include controlling an operating state of the wind turbine based on the control signal.

Description

Technical Field

[0001] The present disclosure relates generally to systems and methods for controlling a wind turbine, and more particularly, to systems and methods for controlling a wind turbine that provides reactive power. Background Art

[0002] Wind power is considered one of the cleanest, most environmentally friendly energy sources currently available, and wind turbines are gaining increasing attention in this regard. Existing electrical power distribution systems (e.g., power grids) can be used to distribute power from renewable energy sources (such as wind) if control systems and methodologies are utilized to coordinate the power generated by the renewable energy source, the power demand on the power distribution system, and the power consumed based on the varying operating conditions that are inherent with the renewable energy source. For example, the operating conditions of a wind turbine may vary based on wind speed or in the absence of wind.

[0003] Since wind power is not a power source with a constant power output in time, but includes variations, the operator of the power distribution system must take this into account. One consequence is, for example, that the distribution and transmission network becomes more difficult to manage. This is also related to the management of the amount of reactive power introduced into the power distribution system.

[0004] Active power is generated or consumed when the voltage and current are in phase. Reactive power is generated or consumed when the voltage and current are out of phase (e.g., 90 degrees). The maintenance of voltage within the electric power distribution system is important for the stability of the system with respect to power delivery and power flow. Failure to maintain voltage within the electric power distribution system can cause adverse consequences and effects on the system, including voltage collapse, which can cause damage to generation, transmission, and distribution equipment and lead to power outages. Reactive power is generated or absorbed by components within the electric power distribution system to maintain the system voltage level, commonly referred to as providing "voltage support" or "voltage regulation." Therefore, reactive power is energy that must be generated for the maintenance and correct operation of the electric power distribution system. The stability of an electric power distribution system (e.g., a power grid) is related to the generation and / or consumption of reactive power; therefore, it is usually necessary to control the reactive power output from renewable energy sources to meet power demand while providing stability to the power grid.

[0005] Wind turbines and wind farms can be used to provide reactive power. The reactive power required for voltage regulation is often generated by one or more wind turbines in a wind farm and proportionally between them based on the reactive power capabilities of each wind turbine. However, when a wind turbine remains in operation to provide reactive power, the wind turbine will consume a certain amount of active power or effective power, even when the reactive power capacity of the wind turbine is not fully utilized. In some cases, a wind turbine used to provide reactive power may cause active power consumption, which is comparable to the active power consumption of a wind turbine that provides significant active power generation. Therefore, in a wind farm setting, the inefficient use of multiple wind turbines that remain in operation to provide reactive power may result in significant and unnecessary active power consumption. Such significant and unnecessary active power consumption wastes available effective power and may result in unnecessary costs for wind farm or wind turbine operators.

[0006] Therefore, systems and methods for controlling wind turbines that provide reactive power that improve efficiency with respect to active or effective power consumption or reduce active or effective power consumption, but maintain the ability of wind turbines and wind farms to provide appropriate amounts of reactive power to the electrical power distribution system would be useful and welcome. Summary of the invention

[0007] 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 exemplary embodiments of the disclosure.

[0008] An exemplary aspect of the present disclosure relates to a method for controlling a wind farm electric power system. The wind farm electric power system may include a controller and one or more wind turbines electrically connected to a power grid via an interconnection point. The method includes receiving one or more signals from a sensor by the controller, the one or more signals being associated with one or more wind turbines. The controller may determine one or more wind turbines operating under low wind or no wind conditions based on the sensor signals. The controller is also used to determine the reactive power capability of the wind turbines operating under low wind or no wind conditions. The method includes generating one or more control signals by the controller based at least in part on the reactive power capability of one or more wind turbines operating under low wind or no wind conditions, and controlling the operating state of one or more wind turbines based at least in part on the one or more control signals.

[0009] Another exemplary aspect of the present disclosure relates to a control system for operating a wind farm electric power system. The wind farm electric power system includes one or more wind turbines electrically connected to a power grid via an interconnection point. The control system includes one or more processors and one or more storage devices. The storage device may be configured to store instructions that, when executed by the processor, cause the processor to perform operations. The operations may include receiving one or more signals from a sensor, the one or more signals being associated with one or more wind turbines, and determining one or more wind turbines operating under low wind or no wind operating conditions based at least in part on the one or more sensor signals. The operations may also include determining the reactive power capability of one or more wind turbines operating under low wind or no wind conditions, generating one or more control signals based at least in part on the reactive power capability of one or more wind turbines operating under low wind or no wind conditions, and controlling the operating state of one or more wind turbines based at least in part on the one or more control signals.

[0010] Another exemplary aspect of the present disclosure relates to a wind farm. The wind farm may include one or more wind turbines electrically connected to a power grid via an interconnection point. The wind farm may include a controller configured to perform one or more operations. The operations may include receiving one or more signals from a sensor, the one or more signals being associated with the one or more wind turbines, and determining one or more wind turbines operating under low wind or no wind operating conditions based at least in part on the one or more sensor signals. The operations may also include determining the reactive power capability of one or more wind turbines operating under low wind or no wind conditions, and generating one or more control signals based at least in part on the reactive power capability of one or more wind turbines operating under low wind or no wind conditions, and controlling the operating state of one or more wind turbines based at least in part on the one or more control signals.

[0011] Technical Solution 1. A method for controlling a wind farm electric power system, wherein the wind farm electric power system comprises a controller and one or more wind turbines electrically connected to a power grid through an interconnection point, the method comprising:

[0012] receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines;

[0013] determining, by the controller, one or more wind turbines operating in low wind or no wind conditions based at least in part on the one or more of the sensor signals;

[0014] determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions;

[0015] generating, by the controller, one or more control signals based at least in part on the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions; and

[0016] An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

[0017] Technical Solution 2. The method according to Technical Solution 1 is characterized in that the method further comprises:

[0018] determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection;

[0019] comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more threshold values; and

[0020] The one or more control signals are generated by the controller based at least in part on the comparison.

[0021] Technical Solution 3. The method according to Technical Solution 2 is characterized in that the one or more thresholds are at least partially based on a hysteresis window associated with the reactive power requirement at the interconnection point, and wherein the one or more thresholds include at least an upper threshold and a lower threshold.

[0022] Technical Solution 4. The method according to Technical Solution 3 is characterized in that controlling the operating state of the one or more wind turbines based at least in part on the one or more control signals further comprises:

[0023] When the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions exceeds the upper threshold, one or more wind turbines operating under low wind or no wind conditions are deactivated.

[0024] Technical Solution 5. The method according to Technical Solution 3 is characterized in that controlling the operating state of the one or more wind turbines based at least in part on the one or more control signals further comprises:

[0025] determining, by the controller based at least in part on the one or more of the sensor signals, one or more wind turbines that are deactivated and positioned in low wind or no wind conditions;

[0026] One or more of the deactivated wind turbines are activated when the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions is less than the lower threshold.

[0027] Technical Solution 6. The method according to Technical Solution 3 is characterized in that the method further comprises:

[0028] identifying, by the controller, an operational runtime for each of the one or more wind turbines, wherein the operational runtime corresponds to a time period during which the one or more wind turbines are in operation and provide reactive power or real power to the power grid; and

[0029] The operational state of one or more wind turbines is controlled based at least in part on the operational runtime of the one or more of the wind turbines.

[0030] Technical Solution 7. The method according to Technical Solution 3 is characterized in that the method further comprises:

[0031] identifying, by the controller, a distance between each of the one or more wind turbines and the point of interconnection; and

[0032] The operational state of one or more wind turbines is controlled based at least in part on the distance between each of the one or more wind turbines and the point of interconnection.

[0033] Technical Solution 8. The method according to Technical Solution 3 is characterized in that the method further comprises:

[0034] comparing, by the controller, the reactive power capability of the one or more wind turbines to the upper threshold;

[0035] comparing, by the controller, the reactive power capability of the one or more wind turbines with the lower threshold when the reactive power capability of the one or more wind turbines is less than the upper threshold;

[0036] generating, by the controller, one or more control signals when the reactive power capability of the one or more wind turbines is less than the lower threshold; and

[0037] The operating state of one or more wind turbines is controlled based at least in part on the one or more control signals such that one or more of the wind turbines are activated and placed in an operating state such that the one or more wind turbines provide reactive power capability to the power grid.

[0038] Technical Solution 9. The method according to Technical Solution 3 is characterized in that the method further comprises:

[0039] identifying, by the controller, a non-operational time period for each of the one or more wind turbines, wherein the non-operational time period corresponds to a time period during which the one or more wind turbines are unable to provide reactive power or real power to the power grid; and

[0040] The operational state of one or more wind turbines is controlled based at least in part on the non-operational time period.

[0041] Technical Solution 10. The method according to Technical Solution 3 is characterized in that the low wind condition includes a wind speed below a wind threshold, and the wind threshold corresponds to the wind volume at which one of the wind turbines can generate an amount of effective power, and the amount of effective power is less than the amount of effective power consumed by the wind turbine.

[0042] Technical Solution 11. A control system for operating a wind farm electric power system, wherein the wind farm electric power system comprises one or more wind turbines electrically connected to a power grid via an interconnection point, the control system comprising:

[0043] one or more processors;

[0044] one or more storage devices, wherein the one or more storage devices are configured to store instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising:

[0045] receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines;

[0046] determining, by the controller, one or more wind turbines operating in low wind or no wind operating conditions based at least in part on the one or more of the sensor signals;

[0047] determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions;

[0048] generating, by the controller, one or more control signals based at least in part on the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions; and

[0049] An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

[0050] Technical Solution 12. The control system according to Technical Solution 11 is characterized in that the operation further comprises:

[0051] determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection;

[0052] comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more threshold values; and

[0053] The one or more control signals are generated by the controller based at least in part on the comparison.

[0054] Technical Solution 13. A control system according to Technical Solution 12, characterized in that the one or more thresholds are at least partially based on a hysteresis window associated with the reactive power requirement at the interconnection point, and wherein the one or more thresholds include at least an upper threshold and a lower threshold.

[0055] Technical Solution 14. The control system according to Technical Solution 13 is characterized in that the operation further comprises:

[0056] When the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions exceeds the upper threshold, one or more wind turbines operating under low wind or no wind conditions are deactivated.

[0057] Technical Solution 15. The control system according to Technical Solution 13 is characterized in that the operation of controlling the operating state of the one or more wind turbines based at least in part on the one or more control signals further comprises:

[0058] determining, by the controller based at least in part on the one or more of the sensor signals, one or more wind turbines that are deactivated and positioned in low wind or no wind conditions;

[0059] One or more of the deactivated wind turbines are activated when the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions is less than the lower threshold.

[0060] Technical Solution 16. The control system according to Technical Solution 13 is characterized in that the operation further comprises:

[0061] identifying, by the controller, an operational runtime for each of the one or more wind turbines, wherein the operational runtime is a period of time during which the one or more wind turbines are in operation to provide reactive power or real power to the power grid; and

[0062] The operational state of one or more wind turbines is controlled based at least in part on the operational runtime of the one or more of the wind turbines.

[0063] Technical Solution 17. The control system according to Technical Solution 13 is characterized in that the operation further comprises:

[0064] identifying, by the controller, a distance between each of the one or more wind turbines and the point of interconnection; and

[0065] The operational state of one or more wind turbines is controlled based at least in part on the distance between each of the one or more wind turbines and the point of interconnection.

[0066] Technical Solution 18. The control system according to Technical Solution 13 is characterized in that the operation further comprises:

[0067] comparing, by the controller, the reactive power capability of the one or more wind turbines to the upper threshold;

[0068] comparing, by the controller, the reactive power capability of the one or more wind turbines with the lower threshold when the reactive power capability of the one or more wind turbines is less than the upper threshold;

[0069] generating, by the controller, one or more control signals when the reactive power capability of the one or more wind turbines is less than the lower threshold; and

[0070] The operating state of one or more wind turbines is controlled based at least in part on the one or more control signals such that one or more of the wind turbines are activated and placed in an operating state such that the one or more wind turbines provide reactive power capability to the power grid.

[0071] Technical Solution 19. The control system according to Technical Solution 13 is characterized in that the operation further comprises:

[0072] identifying, by the controller, a non-operational time period for each of the one or more wind turbines, wherein the non-operational time period is a time period during which the one or more wind turbines are unable to provide reactive power or real power to the power grid; and

[0073] The operational state of one or more wind turbines is controlled based at least in part on the non-operational time period.

[0074] Technical Solution 20. A wind farm, comprising:

[0075] one or more wind turbines electrically connected to an electric power grid via an interconnection point;

[0076] A controller configured to perform one or more operations, the one or more operations comprising:

[0077] receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines;

[0078] determining, by the controller, one or more wind turbines operating in low wind or no wind operating conditions based at least in part on the one or more of the sensor signals;

[0079] determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions;

[0080] determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection;

[0081] comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more threshold values;

[0082] generating, by the controller, the one or more control signals based at least in part on the comparing; and

[0083] An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

[0084] Variations and modifications may be made to these exemplary aspects of the present disclosure. These and other features, aspects and advantages of the various embodiments will become better understood with reference to the following description and the appended claims. The accompanying drawings, which are incorporated in and constitute part of this specification, illustrate embodiments of the present disclosure and, together with the description, serve to illustrate the relevant principles. BRIEF DESCRIPTION OF THE DRAWINGS

[0085] A detailed discussion of embodiments for those skilled in the art is set forth in the specification with reference to the accompanying drawings, in which:

[0086] Figure 1 A perspective view depicting a portion of a wind turbine according to an exemplary embodiment of the present disclosure;

[0087] Figure 2 A schematic diagram depicting a wind turbine electrical power system according to an exemplary embodiment of the present disclosure, the wind turbine electrical power system being suitable for use with Figure 1 Used together with the wind turbine shown in;

[0088] Figure 3 A schematic diagram depicting a wind farm electric power system according to an exemplary embodiment of the present disclosure;

[0089] Figure 4depicts a block diagram of a controller according to an exemplary embodiment of the present disclosure;

[0090] Figure 5 A flow chart depicting an exemplary method of controlling a wind turbine providing reactive power and for reducing active power consumption of the wind turbine;

[0091] Figure 6 a flow chart depicting a portion of an exemplary method of controlling a wind turbine providing reactive power and for reducing active power consumption of the wind turbine; and

[0092] Figure 7 A flow chart depicting a portion of an exemplary method of controlling a wind turbine providing reactive power and for reducing active power consumption of the wind turbine. DETAILED DESCRIPTION

[0093] Reference will now be made in detail to embodiments of the present disclosure, one or more examples of which are shown in the accompanying drawings. Each example is provided by way of illustration of the present disclosure, without limiting the present disclosure. In fact, it will be apparent to those skilled in the art that various modifications and variations may be made in the present disclosure without departing from the scope or spirit of the present disclosure. For example, a feature shown or described as part of one embodiment may be used with another embodiment to produce yet another embodiment. Therefore, it is intended that the present disclosure covers such modifications and variations within the scope of the appended claims and their equivalents.

[0094] With the successful development of wind power, this form of power has gained a huge market share. Since wind power is not a power source with a constant power output in time, but includes variations due to, for example, changes in wind speed, the operator of the power distribution network must take this into account. One of the consequences is that, for example, the distribution and transmission network becomes more difficult to manage. This is also related to the management of the amount of reactive power flows in the network.

[0095] Exemplary aspects of the present disclosure relate to systems and methods for controlling a wind turbine, and more specifically, to systems and methods for controlling a wind turbine that provides reactive power. The ability of a wind turbine to generate active power is based on environmental conditions, including wind conditions. During no wind or low wind conditions, a wind turbine can be used to provide reactive power capabilities for voltage regulation (e.g., voltage support), reactive power (e.g., VAR, volt-ampere reactive), and power factor (Pf) regulation. No wind conditions exist when the wind speed at the wind turbine is below a wind speed threshold, which represents the minimum amount of wind required to rotate the rotor and rotor blades. Low wind conditions exist when the wind speed is below a wind speed threshold, at which there is insufficient wind to allow the wind turbine to generate or generate an amount of active power that exceeds the amount of active power consumed by the wind turbine to maintain operation. In other words, the wind speed available at the wind turbine is such that the wind turbine cannot generate enough active power to meet the effective power demand or need of the wind turbine. Low wind conditions may also represent stable wind conditions that will cause the rotor of the wind turbine to move beyond the cut-in speed of the turbine (such stable wind conditions are typically steady state wind speeds of approximately 3 to 4 m / s).

[0096] In many cases, there is no requirement or need for reactive power capability beyond that required for voltage regulation, VAR, and power factor regulation based on current grid conditions. In many cases, wind turbines connected to the power grid have reactive power capabilities that exceed the requirements of the power grid. In this regard, exemplary aspects of the present disclosure relate to systems and methods for controlling wind turbines and wind farms so that reactive power can be provided at the wind farm or wind turbine's point of interconnection (POI) to the power grid when the wind turbine or one or more wind turbines in the wind farm are not being used for active or real power generation.

[0097] According to exemplary aspects of the systems and methods of the present disclosure, wind turbines and wind farms may be dynamically managed or controlled so that these renewable energy sources (e.g., wind turbines) operate more efficiently with respect to active power consumption while also maintaining the ability of the wind turbines and wind farms to provide an appropriate amount of reactive power to an electrical power distribution system or power grid. When wind turbines remain in operation during low wind or no wind conditions, the wind turbines and wind farms consume a certain amount of active power or cause a certain amount of active power consumption, even when the wind farm controller does not fully utilize some or all of the wind turbines to provide reactive power. When operating a wind turbine or multiple wind turbines within a wind farm to provide reactive power, it may be beneficial to adjust or control which wind turbines provide reactive power based at least in part on the reactive power required to adjust the voltage, VAR, and / or Pf at a POI between the wind turbine or wind farm and the power grid. Wind turbines operating in no wind or low wind conditions, or those providing reactive power under other conditions, may be dynamically and efficiently managed by exemplary embodiments of the systems and methods of the present disclosure by selectively activating or deactivating one or more of the wind turbines based on one or more characteristics of the wind turbines (e.g., wind turbine size, location, age, maintenance status), characteristics of the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), characteristics of the loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0098] According to exemplary aspects of the systems and methods of the present disclosure, wind turbines can be dynamically managed so that a minimum or near minimum number of wind turbines remain activated to maintain desired reactive power conditions at a POI during no wind or low wind conditions. Dynamic management of wind turbines that provide reactive power by selectively activating (i.e., turning on or entering an operational state) or deactivating (i.e., turning off or entering a non-operating state) based on one or more characteristics of the wind turbine, the power grid, the load on the grid, and / or environmental conditions is advantageous with respect to the operation of the wind farm or wind turbines, and allows smooth, continuous, appropriate, and rapid voltage regulation and voltage support under most (if not all) operating conditions, and can have the technical effects and benefits of providing grid reinforcement and an appropriate or required amount of reactive power, while simultaneously providing the advantage of reducing the active power consumed by inactive wind turbines and / or wind turbines that do not fully utilize their reactive power capabilities. In this way, exemplary aspects of the present disclosure can provide many technical effects and benefits, including reducing or eliminating unnecessary consumption and waste of available active power by wind turbines, and reducing the operating costs of wind farm or wind turbine owners or operators.

[0099] Dynamic management of wind turbines that provide reactive power by selective activation and deactivation can also allow for the reduction or elimination of grid reinforcement that is specifically designed or required for no wind or low wind conditions. Such systems and methods also provide the advantages of existing wind turbines to provide the reactive power necessary for grid support so that other generation resources that can be connected to the grid can be more efficiently or economically used for power generation and distribution. The technical effects and benefits of such advantages include more economical system operation by reducing or eliminating the requirements for transmission reinforcement, and reducing or eliminating the consumption of active power by wind turbines (which do not contribute to meeting the reactive power requirements of the grid). Other technical effects and benefits of such advantages of the exemplary system or method of the present disclosure include enhanced grid security for grid events, strict voltage regulation under changing conditions, security from system voltage disturbances, and reduced requirements for the necessary operation generation of other generation resources for connection to the grid, which must be operated to supply active power to inactive wind turbines and / or wind farms. In this way, the exemplary aspects of the present disclosure can provide many technical effects and benefits.

[0100] Referring now to the drawings, exemplary aspects of the present disclosure will be discussed in further detail.

[0101] Figure 1 A wind turbine 10 is depicted according to an exemplary embodiment of the present disclosure. As shown, the wind turbine 10 includes a nacelle 14 that typically houses a generator 28 (in Figure 2 1 ). A nacelle 14 is mounted on a tower 12 that extends from a supporting surface. The wind turbine 10 also includes a rotor 16 that includes a plurality of rotor blades 20 attached to a rotating hub 18.

[0102] Figure 2 A wind turbine power system 100 is depicted, which includes a wind turbine 10 and an associated power system 102 suitable for use with the wind turbine 10. When wind strikes the rotor blades 20, the blades 20 convert wind energy into a mechanical rotational torque, which rotatably drives a low-speed shaft 22. The low-speed shaft 22 is configured to drive a gearbox 24 (where present), which then steps up the low rotational speed of the low-speed shaft 22 to drive a high-speed shaft 26 at an increased rotational speed. The high-speed shaft 26 is generally rotatably coupled to a generator 28 (such as a doubly fed induction generator or DFIG) so as to rotatably drive a generator rotor 30. In this regard, a rotating magnetic field can be induced by the generator rotor 30, and a voltage can be induced within a generator stator 32 that is magnetically coupled to the generator rotor 30. The associated electrical power can be transmitted from the generator stator 32 to a main three-winding transformer 34, which is connected to the power grid at the POI 56 via a grid breaker 36. Therefore, the main transformer 34 steps up the voltage amplitude of the electric power so that the converted electric power can be further transmitted to the power grid.

[0103] In addition, as shown, the generator 28 is electrically coupled to a bidirectional power converter 38, which includes a rotor side converter 40 connected to a line side converter 42 via a regulated DC link 44. The rotor side converter 40 converts the AC power provided from the rotor 30 into DC power and provides the DC power to the DC link 44. The line side converter 42 converts the DC power on the DC link 44 into an AC output power suitable for the power grid. Thus, the AC power from the power converter 38 can be combined with the power from the stator 32 to provide a multi-phase power (e.g., three-phase power) having a frequency that is substantially maintained at the frequency of the power grid (e.g., 50 Hz / 60 Hz).

[0104] The three-winding transformer 34 shown may have (1) a 33 kilovolt (kV) medium voltage (MV) primary winding 33 connected to the power grid, (2) a 6 to 13.8 kV MV secondary winding 35 connected to the generator stator 32, and (3) a 690 to 900 volt (V) low voltage (LV) tertiary winding 37 connected to the line-side power converter 42.

[0105] Figure 3 A schematic diagram depicting one embodiment of a wind farm electric power system 200 according to an exemplary embodiment of the present disclosure. The wind farm electric power system 200 may include a plurality of wind turbine power systems 100 connected to an electric power grid via a POI 56. The wind farm electric power system 200 may include at least two clusters 204 to form the electric power system 200. A single wind turbine power system 100 including a plurality of wind turbines 10 may be arranged at a predetermined geographic location and electrically connected together to form a wind farm 202.

[0106] The electrical power associated with each wind turbine power system 100 may be transmitted to the mains 206 via one or more cluster lines 220. Each wind turbine power system 100 may be connected to or disconnected from the one or more cluster lines 220 via one or more switches or circuit breakers 222. The wind turbine power system 100 may be arranged into a plurality of groups (or clusters) 204, wherein each group is individually connected to the mains 206 via switches 208, 210, 212, respectively. Thus, as shown, each cluster 204 may be connected to a separate transformer 214, 216, 218 via switches 208, 210, 212, respectively, for stepping up the voltage amplitude of the electrical power from each cluster 204 so that the converted electrical power can be further transmitted to the power grid. In addition, as shown, the transformers 214, 216, 218 are connected to the mains 206, which combine the voltages from each cluster 204 before sending the power to the grid via the POI 56. POI 56 may be a circuit breaker, switch, or other known method of connecting to the power grid.

[0107] Each wind turbine power system 100 may include one or more controllers, such as a turbine controller 224. The turbine controller 224 may be configured to control components of the wind turbine power system 100 (including the switch 222), and / or implement some or all of the method steps as described herein. The turbine controller 224 may be located on or within each wind turbine 10, or may be located remotely from each wind turbine 10. The turbine controller 224 may be part of or included with respect to one or more of the other controllers associated with the wind turbine power system 100 and / or the wind farm electric power system 200. Turbine controller 224 may operate switch 222 to connect or disconnect one or more wind turbine power systems 100 from cluster line 220 based at least in part on the reactive power required at POI 56 and / or at least in part on characteristics of wind turbine power system 100, wind farm electric power system 200, and / or characteristics of wind turbine 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0108] The wind farm electric power system 200 may include one or more controllers, such as a wind farm controller 226. The wind farm controller 226 may be configured to control components of the wind farm electric power system 200 (including switches 208, 210, and 212), and / or implement some or all of the method steps as described herein. The wind farm controller 226 may be located within a geographic area of ​​the wind farm electric power system 200, or any portion thereof, or may be located remotely from the wind farm electric power system 200, or any portion thereof. The wind farm controller 226 may be part of or included with respect to one or more of the wind turbine power systems 100 and / or one or more of the other controllers associated with the wind farm electric power system 200. Each of the cluster 204, the wind turbine power system 100, or the turbine controller 224 may be communicatively coupled to the wind farm controller 226.

[0109] The wind farm controller 226 may generate and send control signals to the turbine controller 224 to operate the switch 222 to connect or disconnect one or more wind turbine power systems 100 from the cluster line 220 based at least in part on the reactive power required at the POI 56. The wind farm controller 226 may generate and send control signals to the switches 208, 210, and / or 212 to connect or disconnect one or more of the clusters 204 based at least in part on the reactive power required at the POI 56 and / or based at least in part on characteristics of the wind turbine power systems 100, the wind farm electrical power system 200, and / or characteristics of the wind turbines 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0110] Figure 4 A block diagram of a controller 400 is depicted according to an exemplary embodiment of the present disclosure. The controller 400 may be a turbine controller 224 or a wind farm controller 226. The controller 400 may include one or more processors 402 and associated storage devices 404 configured to perform various computer-implemented functions (e.g., perform methods, steps, calculations, etc., and store related data, as disclosed herein). The storage device 404 may also store data related to certain characteristics of the wind turbine power system 100, the wind farm electric power system 200, and / or characteristics of the wind turbine 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0111] Additionally, the controller 400 may include a communication module 406 to facilitate communication between the controller and various components of the wind turbine power system 100, the wind farm electric power system 200, and / or the wind farm controller 226, including communication between the wind farm controller 226 and the turbine controller 224. Additionally, the communication module 406 may include a sensor interface 408 (e.g., one or more analog-to-digital converters) to allow signals transmitted from one or more sensors 410, 412, and 414 to be converted into signals that can be understood and processed by the processor 402. Sensors 410, 412, and 414 may be used to measure, determine, or collect data regarding characteristics of wind turbine power system 100, wind farm electric power system 200, and / or characteristics of wind turbine 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0112] The controller 400 may also include a user interface 416. The user interface 416 may have various configurations and control mechanisms, which may be installed in or located in the user interface 416. The user interface 416 may also be located in a geographic area of ​​the wind farm electric power system 200 or any portion thereof, or may be located remotely from the wind farm electric power system 200 or any portion thereof. The user interface 416 may include an input member 418. The input member 418 may be, for example, a capacitive touch screen. The input member 418 may allow selective activation, adjustment or control of the wind farm controller 226 and the turbine controller 224 and any timer features or other user-adjustable inputs. One or more of a variety of electrical, mechanical or electromechanical input devices including rotary dials, buttons, and touch pads may also be used alone or in combination as the input member 418. The user interface 416 may include a display member, such as a digital or analog display device, which is designed to provide operational feedback to the user.

[0113] It should be appreciated that the sensors 410, 412, and 414 may be communicatively coupled to the communication module 406 using any suitable means. For example, the sensors 410, 412, and 414 may be coupled to the sensor interface 408 via a wired connection. However, in other embodiments, the sensors 410, 412, and 414 may be coupled to the sensor interface 408 via a wireless connection (such as by using any suitable wireless communication protocol known in the art). In this regard, the processor 402 may be configured to receive one or more signals from the sensors 410, 412, and 414. The sensors 410, 412, and 414 may be part of or included with respect to one or more of the other controllers associated with one or more of the wind turbine power systems 100 and / or the wind farm electric power system 200. The sensors 410, 412, and 414 may also be located within a geographic area of ​​the wind farm electric power system 200 or any portion thereof, or may be remotely located from the wind farm electric power system 200 or any portion thereof.

[0114] It should also be understood that sensors 410, 412, and 414 may be any number or type of voltage and / or current sensors that may be employed within wind turbine power system 100 and at any location. For example, the sensors may be current transformers, shunt sensors, Rogowski coils, Hall effect current sensors, micro inertial measurement units (MIMUs), or the like, and / or any other suitable voltage or current sensors now known or later developed in the art. Thus, one or more controllers (such as wind farm controller 226 and turbine controller 224) are configured to receive one or more voltage and / or current feedback signals from sensors 410, 412, and 414.

[0115] As used herein, the term "processor" refers not only to what is known in the art as an integrated circuit included in a computer, but also to controllers, microcontrollers, microcomputers, programmable logic controllers (PLCs), application specific integrated circuits, and other programmable circuits. The processor 402 is also configured to calculate advanced control algorithms and communicate with a variety of Ethernet or serial-based protocols (Modbus, OPC, CAN, etc.). In addition, the (multiple) storage device 404 may generally include (multiple) storage elements, which include but are not limited to computer-readable media (e.g., random access memory (RAM)), computer-readable non-volatile media (e.g., flash memory), floppy disks, compact disk read-only memory (CD-ROM), magneto-optical disks (MOD), digital versatile disks (DVD), and / or other suitable storage elements. Such (multiple) storage devices 140 may generally be configured to store suitable computer-readable instructions, which when implemented by the (multiple) processors 402 configure the controller to perform various functions, as described herein.

[0116] Figure 5 A flow chart depicting an exemplary method 500 for controlling a wind turbine in a wind farm to provide reactive power and reduce active power consumption of the wind turbine according to an exemplary embodiment of the present disclosure. The method 500 may be performed by one or more controllers, such as the wind farm controller 226 and / or the turbine controller 224, and by other devices included with respect to the wind turbine power system 100 and / or the wind farm electric power system 200. Figure 5 The steps of method 500 are depicted as being performed in a particular order for purposes of illustration and discussion. Those skilled in the art, using the disclosure provided herein, will appreciate that the methods discussed herein may be altered, rearranged, expanded, omitted, performed simultaneously, or modified in various ways without departing from the scope of the present disclosure.

[0117] At (502), the method may include receiving a start signal that initiates a control algorithm for providing reactive power and reducing active power consumption based on the wind turbine. The start signal may be generated and / or received by one or more controllers, such as wind farm controller 226 and / or turbine controller 224. The start signal may be generated by one or more controllers, such as wind farm controller 226 and / or turbine controller 224, in response to a user input or interaction with one or more controllers indicating a desire to initiate method 500. The user input may be provided via a user interface, such as user interface 416 ( Figure 4 The activation signal may be generated by one or more controllers (e.g., wind farm controller 226 and / or turbine controller 224) in response to one or more signals received from sensors 410, 412, and 414 indicating a need for reactive power at POI 56 or indicating one or more environmental conditions (e.g., low wind or no wind conditions at one or more wind turbines 10).

[0118] At (504), the method may include determining, by one or more controllers, a number of wind turbines 10 that are currently activated and capable of providing reactive power. Such a determination may be made based at least in part on one or more signals received by one or more controllers (e.g., wind farm controller 226 and / or turbine controller 224) from sensors 410, 412, and 414 indicating an operational state of one or more wind turbines 10 or indicating one or more environmental conditions (e.g., low wind or no wind conditions at one or more wind turbines 10). At (504), if the number of wind turbines 10 capable of providing reactive power is greater than zero, the method 500 proceeds to (506). If no wind turbines 10 are capable of providing reactive power, the method 500 returns to (502).

[0119] At (506), the method may include determining, by the wind farm controller 226, an amount of reactive power that can be provided by the one or more wind turbines 10 that are determined at (504) to be currently activated and capable of providing reactive power. More specifically, at (506), the wind farm controller 226 determines the total amount of reactive power (i.e., Q CAP_margin ), one or more wind turbines 10 are activated or operational and are able to provide reactive power.

[0120] At (508), the method may include determining, by the wind farm controller 226, an amount of reactive power required at the POI 56. The wind farm controller 226 determines the amount of reactive power required at the POI 56 (ie, Q) via a reactive power (VAR) regulator. _UppThd , upper threshold). The amount of reactive power required at the POI 56 is the amount of reactive power required for voltage regulation, VAR, and power factor regulation based on current grid conditions.

[0121] At (508), the method also includes determining, by the wind farm controller 226, the total amount of reactive power available from one or more wind turbines 10 (that are activated or operational and capable of providing reactive power) (ie, Q CAP_margin ) and the amount of reactive power required at POI 56 (i.e., Q _UppThd ) comparison. In some cases, Q _UppThd may correspond to an upper limit of a hysteresis window associated with the amount of reactive power required at POI 56. The hysteresis window associated with POI 56 represents fluctuations in the amount of reactive power present at POI 56 that do not adversely affect the stability of the power grid. In some cases, the hysteresis window is based on tolerances of electrical equipment at POI 56 or in electrical power system 200. In some cases, the hysteresis window is within 10% of the amount of reactive power required at POI 56 to maintain the stability of the power grid. If Q CAP_margin Greater than Q _UppThd , then method 500 proceeds to (510). If Q CAP_margin Less than Q _UppThd , then method 500 proceeds to (511).

[0122] At (510), the method may include resetting or canceling one or more control signals or settings (i.e., TurnOn_Integrator) utilized by the wind farm controller 226 to establish a predetermined time period, after which an activation control signal may be generated by the wind farm controller 226 to turn on or activate one or more wind turbines 10 or to drive one or more wind turbines 10 to operate so that the one or more wind turbines 10 can provide reactive power.

[0123] At (512), the method may include the wind farm controller 226 generating or implementing one or more control signals or settings (i.e., TurnOff_Integrator) utilized by the wind farm controller 226 to establish a predetermined time period after which a deactivation control signal may be generated by the wind farm controller 226 to shut down or deactivate one or more wind turbines 10 such that the one or more wind turbines 10 are unable to provide reactive power and do not consume active power. For example, the TurnOff_Integrator may be associated with a predetermined time period that is specific to or based at least in part on characteristics of a particular wind turbine power system 100, a particular wind farm electric power system 200, and / or characteristics of the wind turbines 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0124] At (514), the method may include the wind farm controller 226 comparing the TurnOff_Integrator control signal to a threshold value (i.e., Cnt_Thd). Cnt_Thd may correspond to zero or expiration of a predetermined time period associated with the TurnOff_Integrator control signal. At (514), if TurnOff_Integrator is greater than Cnt_Thd, the method 500 returns to (502). If TurnOff_Integrator is less than or equal to Cnt_Thd, the method 500 proceeds to (516).

[0125] At (516), the method may include wind farm controller 226 generating a deactivation control command to deactivate one or more wind turbines such that the operating state of the one or more turbines is such that the one or more wind turbines are unable to provide reactive power and therefore do not consume active power. The deactivation control command may be executed by wind farm controller 226. Alternatively, the deactivation control command may be transmitted from wind farm controller 226 to one or more wind turbine controllers 224 and executed by one or more wind turbine controllers 224.

[0126] At (518), the method may include resetting or canceling one or more control signals or settings utilized by the wind farm controller 226 (i.e., TurnOff_Integrator) to establish a predetermined time period after which a disable control signal may be generated by the wind farm controller 226 to shut down or disable one or more wind turbines 10 such that the one or more turbines 10 are unable to provide reactive power. After TurnOff_Integrator is reset or canceled at (518), the method 500 returns to (502).

[0127] At (511), the method also includes determining, by the wind farm controller 226, the total amount of reactive power (i.e., Q) available from one or more wind turbines 10 (that are activated or operational and capable of providing reactive power). CAP_margin ) and the lower threshold (i.e., Q _LowThd , lower threshold) comparison. In some cases, the lower threshold Q _LowThd may correspond to the lower limit of the hysteresis window associated with the amount of reactive power required at the POI 56. At (511), if Q CAP_margin Greater than Q _LowThd , then method 500 proceeds to (513). However, if Q CAP_margin Less than Q _LowThd , then method 500 proceeds to (515).

[0128] At (513), the method may include resetting or deactivating one or more control signals or settings (i.e., TurnOn_Integrator and TurnOff_Integrator) utilized by the wind farm controller 226 to establish one or more predetermined time periods after which the activation control signals may be based at least in part on the interconnection point (e.g., Figure 3 The reactive power demand at the POI 56 shown in FIG. 5 is generated by the wind farm controller 226 for turning on or activating and / or turning off or deactivating one or more wind turbines 10. After (513), the method 500 returns to (502).

[0129] At (515), the method may include resetting or canceling one or more control signals or settings (i.e., TurnOff_Integrator) utilized by the wind farm controller 226 to establish a predetermined time period, after which a deactivation control signal may be generated by the wind farm controller 226 to shut down or deactivate one or more wind turbines 10 such that the one or more turbines 10 are unable to provide reactive power and do not consume active power.

[0130] At (517), the method may include the wind farm controller 226 generating or implementing one or more control signals or settings (i.e., TurnOn_Integrator) utilized by the wind farm controller 226 to establish a predetermined time period after which an activation control signal may be generated by the wind farm controller 226 to turn on or activate one or more wind turbines 10 so that the one or more turbines 10 can provide reactive power to meet the POI (e.g., Figure 3 For example, the TurnOn_Integrator may be associated with a predetermined time period that is specific to or based at least in part on characteristics of a particular wind turbine power system 100, a particular wind farm electric power system 200, and / or characteristics of wind turbines 10 (e.g., wind turbine size, location, age, maintenance status), the power grid (e.g., strength or condition of the grid, strength or condition of the wind farm or wind turbine connection to the grid, grid architecture, grid location), loads on the grid (e.g., heavy or variable loads), and / or environmental conditions (e.g., wind conditions for one or more wind turbines).

[0131] At (519), the method may include comparing the TurnOn_Integrator control signal to a threshold value (i.e., TurnOn_Cnt_Thd) by one or more controllers (e.g., wind farm controller 226). TurnOn_Cnt_Thd may correspond to zero or the expiration of a predetermined time period associated with the TurnOn_Integrator control signal. At (514), if TurnOn_Integrator is greater than TurnOn_Cnt_Thd, the method 500 returns to (502). If TurnOn_Integrator is less than or equal to TurnOn_Cnt_Thd, the method 500 proceeds to (521).

[0132] At (521), the method may include one or more controllers (such as wind farm controller 226) generating an activation control command to activate one or more wind turbines such that the operating state of the one or more turbines enables the one or more wind turbines to provide reactive power. The activation control command may be executed by wind farm controller 226. Alternatively, the activation control command may be transmitted from wind farm controller 226 to one or more wind turbine controllers 224 and executed by one or more wind turbine controllers 224.

[0133] At (523), the method may include resetting or canceling one or more control signals or settings (i.e., TurnOn_Integrator) utilized by the wind farm controller 226 to establish a predetermined time period after which an activation control signal may be generated by the wind farm controller 226 to turn on or activate one or more wind turbines 10 so that the one or more turbines 10 can provide reactive power. After TurnOn_Integrator is reset or canceled at (523), the method 500 returns to (502).

[0134] Figure 6 A flow chart depicting a portion of an exemplary method 600 of controlling a wind turbine in a wind farm to provide reactive power and reduce active power consumption of the wind turbine according to an exemplary embodiment of the present disclosure. More specifically, Figure 6 A flow chart depicting an exemplary method 600 for selectively activating and / or deactivating wind turbines in a wind farm providing reactive power and reducing active power consumption of wind turbines according to an exemplary embodiment of the present disclosure. The method 600 may be performed by one or more controllers, such as the wind farm controller 226 and / or the turbine controller 224, and by other devices included with respect to the wind turbine power system 100 and / or the wind farm electric power system 200. The method 600 may be performed in conjunction with or concurrently with the method 500. More specifically, the method 600 may be performed after method steps (516) and / or (521) of the method 500. Figure 6 The steps of method 600 are depicted as being performed in a particular order for purposes of illustration and discussion. Those skilled in the art, using the disclosure provided herein, will appreciate that the methods discussed herein may be altered, rearranged, expanded, omitted, performed simultaneously, or modified in various ways without departing from the scope of the present disclosure.

[0135] At (602), the method may include receiving a start signal that initiates a control algorithm for selectively activating and / or deactivating wind turbines that provide reactive power and reducing active power consumption based on the wind turbines. The start signal may be generated and / or received by one or more controllers, such as wind farm controller 226 and / or turbine controller 224. The start signal may be generated by one or more controllers, such as wind farm controller 226 and / or turbine controller 224, in response to a user input or interaction with one or more controllers indicating a desire to initiate method 500. The user input may be provided via a user interface, such as user interface 416 ( Figure 4 Alternatively, the start signal at (602) may be the deactivation control command generated at (516) or the activation control command generated at (521).

[0136] At (604), the method may include detecting, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), generation of a deactivation command (e.g., the command generated at (516) of method 500) by wind farm controller 226. If a deactivation command is detected, the method proceeds to (606). If a deactivation command is not detected, the method proceeds to (605).

[0137] At (606), the method may include determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), certain characteristics of one or more wind turbines 10, including determining which turbines are activated to provide reactive power capability. At (606), the method also includes determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), wind turbines 10 that include the longest operating time or are activated for the longest period of time. Such determination is based at least in part on data collected and / or stored at wind turbine controller 224 relating to the period of time during which each of the one or more wind turbines 10 is operated.

[0138] At (608), the method may include selecting, by the one or more controllers, one or more wind turbines 10 to deactivate based at least in part on the comparison of the timer period, each of the one or more wind turbines 10 not operating during the timer period. At (608), the method may also include generating a deactivation control command based at least in part on the comparison of the time period to deactivate the one or more wind turbines such that the operating state of the one or more turbines that were not operating for the minimum amount of time is such that the one or more wind turbines are unable to provide reactive power and therefore do not consume active power, each of the one or more wind turbines not operating during the time period.

[0139] At (610), the method may include activating one or more timers or control settings utilized by the wind farm controller 226 or the wind turbine controller 224 to monitor or record data related to a time period during which one or more wind turbines 10 are unable to provide reactive power and therefore do not consume active power, and during which one or more wind turbines 10 remain disabled or in a non-operating state. After the one or more timers are set at (610), the method 600 returns to (602).

[0140] At (605), the method may include detecting, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), generation of an activation command (e.g., the command generated at (521) of method 500) by wind farm controller 226. If an activation command is detected, the method proceeds to (607). If an activation command is not detected, the method returns to (602).

[0141] At (607), the method may include determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), certain characteristics of one or more wind turbines 10, including determining which turbines are not activated to provide reactive power. At (607), the method also includes determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), wind turbines 10 that include the longest non-operational time or are deactivated for the longest period of time. Such determination is based at least in part on data collected and / or stored at wind turbine controller 224 relating to the time period during which each of the one or more wind turbines 10 was not operating.

[0142] At (609), the method may include selecting, by the one or more controllers, one or more wind turbines 10 to activate based at least in part on the comparison of the time periods, each of the one or more wind turbines 10 being inoperative during the time periods. At (609), the method may also include generating an activation control command based at least in part on the comparison of the time periods to activate the one or more wind turbines such that the operating state of the one or more turbines that were inoperative for the maximum amount of time enables the one or more wind turbines to provide reactive power, each of the one or more wind turbines being inoperative during the time periods.

[0143] At (611), the method may include activating one or more timers or control settings utilized by wind farm controller 226 or wind turbine controller 224 to monitor or record data related to a time period during which one or more wind turbines 10 are enabled to provide reactive power. After one or more timers are set at (611), method 600 returns to (602).

[0144] Figure 7 A flow chart depicting a portion of an exemplary method 700 of controlling a wind turbine in a wind farm to provide reactive power and reduce active power consumption of the wind turbine according to an exemplary embodiment of the present disclosure. More specifically, Figure 7 A flow chart depicting an exemplary method 6700 for selectively activating and / or deactivating wind turbines in a wind farm providing reactive power and reducing active power consumption of wind turbines according to an exemplary embodiment of the present disclosure. The method 700 may be performed by one or more controllers, such as the wind farm controller 226 and / or the turbine controller 224, and by other devices included with respect to the wind turbine power system 100 and / or the wind farm electric power system 200. The method 700 may be performed in conjunction with or concurrently with the methods 500 and / or 600. More specifically, the method 700 may be performed after method steps (516) and / or (521) of the method 500. Figure 7The steps of method 700 are depicted as being performed in a particular order for purposes of illustration and discussion. Those skilled in the art, using the disclosure provided herein, will appreciate that the methods discussed herein may be altered, rearranged, expanded, omitted, performed simultaneously, or modified in various ways without departing from the scope of the present disclosure.

[0145] At (702), the method may include receiving a start signal that initiates a control algorithm for selectively activating and / or deactivating wind turbines that provide reactive power and reducing active power consumption based on the wind turbines. The start signal may be generated and / or received by one or more controllers, such as wind farm controller 226 and / or turbine controller 224. The start signal may be generated by one or more controllers, such as wind farm controller 226 and / or turbine controller 224, in response to a desired user input or interaction with one or more controllers indicating a desire to initiate method 700. The user input may be provided via a user interface, such as user interface 416 ( Figure 4 Alternatively, the start signal at (702) may be the deactivation control command generated at (516) or the activation control command generated at (521).

[0146] At (704), the method may include detecting, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), generation of a deactivation command (e.g., the command generated at (516) of method 500) by wind farm controller 226. If a deactivation command is detected, the method proceeds to (706). If a deactivation command is not detected, the method proceeds to (705).

[0147] At (706), the method may include determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), certain characteristics of one or more wind turbines 10, including determining which turbines are activated to provide reactive power capabilities. At (606), the method also includes determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), a wind turbine 10 located at a location farthest from a point of interconnection (e.g., POI 56). Such determination is based at least in part on data collected and / or stored at wind turbine controller 224 or wind farm controller 226 regarding the physical location of each of the one or more wind turbines 10.

[0148] At (708), the method may include selecting, by one or more controllers, one or more wind turbines 10 for deactivation based at least in part on a comparison of the physical distances of each of the one or more wind turbines 10 from the POI 56. At (708), the method may also include generating a deactivation control command based at least in part on a comparison of the physical distances of each of the one or more wind turbines from the POI 56 to deactivate the one or more wind turbines such that the operating state of the one or more turbines furthest from the POI is deactivated such that the one or more wind turbines are unable to provide reactive power and therefore do not consume active power. After (708), the method 700 returns to (702).

[0149] At (705), the method may include detecting, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), generation of an activation command (e.g., the command generated at (521) of method 500) by wind farm controller 226. If an activation command is detected, the method proceeds to (707). If an activation command is not detected, the method returns to (702).

[0150] At (707), the method may include determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), certain characteristics of one or more wind turbines 10, including determining which turbines are physically closest to POI 56. At (707), the method also includes determining, by one or more controllers (e.g., wind turbine controller 224 or wind farm controller 226), the wind turbine 10 that is physically closest to POI 56. Such determination is based at least in part on data collected and / or stored at wind turbine controller 224 or wind farm controller 226 regarding the physical location of each of the one or more wind turbines 10.

[0151] At (709), the method may include selecting, by one or more controllers, one or more wind turbines 10 to activate based at least in part on a comparison of the physical distances of each of the one or more wind turbines 10 from the POI 56. At (709), the method may also include generating an activation control command based at least in part on a comparison of the physical distances of each of the one or more wind turbines from the POI 56 to activate the one or more wind turbines such that the operating state of the one or more turbines physically closest to the POI is activated to enable the one or more wind turbines to provide reactive power to the power grid. After (709), the method 700 returns to (702).

[0152] This written description uses examples to disclose the invention (including the best mode) and also to enable those 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. If these other examples include structural elements that do not differ from the literal language of the claims, or if these other examples include equivalent structural elements that are not significantly different from the literal language of the claims, then these other examples are intended to be within the scope of the claims.

Claims

1. A method for controlling a wind farm electric power system, wherein the wind farm electric power system comprises a controller and one or more wind turbines electrically connected to a power grid via an interconnection point, the method comprising: receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines; determining, by the controller, one or more wind turbines operating in low wind or no wind conditions based at least in part on the one or more of the sensor signals; determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions; determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection; identifying, by the controller, a distance between each of the one or more wind turbines and the point of interconnection; comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more thresholds, wherein the one or more thresholds are based at least in part on a hysteresis window associated with the reactive power requirement at the point of interconnection, and wherein the one or more thresholds include at least an upper threshold and a lower threshold; generating, by the controller, one or more control signals based at least in part on the reactive power capability of the one or more wind turbines operating in low wind or no wind conditions, the comparison of the reactive power capability to the one or more threshold values, and the distance between each of the one or more wind turbines and the point of interconnection; as well as An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

2. The method according to claim 1, characterized in that Controlling the operational state of the one or more wind turbines based at least in part on the one or more control signals further comprises: When the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions exceeds the upper threshold, one or more wind turbines operating under low wind or no wind conditions are deactivated.

3. The method according to claim 1, characterized in that Controlling the operational state of the one or more wind turbines based at least in part on the one or more control signals further comprises: determining, by the controller based at least in part on the one or more of the sensor signals, one or more wind turbines that are deactivated and positioned in low wind or no wind conditions; One or more of the deactivated wind turbines are activated when the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions is less than the lower threshold.

4. The method according to claim 1, characterized in that The method further comprises: identifying, by the controller, an operational runtime for each of the one or more wind turbines, wherein the operational runtime corresponds to a time period during which the one or more wind turbines are in operation and provide reactive power or real power to the power grid; and The operational state of one or more wind turbines is controlled based at least in part on the operational runtime of the one or more of the wind turbines.

5. The method according to claim 1, characterized in that The method further comprises: comparing, by the controller, the reactive power capability of the one or more wind turbines to the upper threshold; comparing, by the controller, the reactive power capability of the one or more wind turbines with the lower threshold when the reactive power capability of the one or more wind turbines is less than the upper threshold; generating, by the controller, one or more control signals when the reactive power capability of the one or more wind turbines is less than the lower threshold; and The operating state of one or more wind turbines is controlled based at least in part on the one or more control signals such that one or more of the wind turbines are activated and placed in an operating state such that the one or more wind turbines provide reactive power capability to the power grid.

6. The method according to claim 1, characterized in that The method further comprises: identifying, by the controller, a non-operational time period for each of the one or more wind turbines, wherein the non-operational time period corresponds to a time period during which the one or more wind turbines are unable to provide reactive power or real power to the power grid; and The operational state of one or more wind turbines is controlled based at least in part on the non-operational time period.

7. The method according to claim 1, characterized in that The low wind condition comprises a wind speed below a wind threshold corresponding to an amount of wind at which one of the wind turbines can generate an amount of active power that is less than an amount of active power consumed by the wind turbine.

8. A controller for operating a wind farm electric power system, wherein the wind farm electric power system comprises one or more wind turbines electrically connected to an electric power grid via an interconnection point, the controller comprising: one or more processors; one or more storage devices, wherein the one or more storage devices are configured to store instructions that, when executed by the one or more processors, cause the one or more processors to perform operations comprising: receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines; determining, by the controller, one or more wind turbines operating in low wind or no wind operating conditions based at least in part on the one or more of the sensor signals; determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions; determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection; identifying, by the controller, a distance between each of the one or more wind turbines and the point of interconnection; comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more thresholds, wherein the one or more thresholds are based at least in part on a hysteresis window associated with the reactive power requirement at the point of interconnection, and wherein the one or more thresholds include at least an upper threshold and a lower threshold; generating, by the controller, one or more control signals based at least in part on the reactive power capability of the one or more wind turbines operating in low wind or no wind conditions, the comparison of the reactive power capability to the one or more threshold values, and the distance between each of the one or more wind turbines and the point of interconnection; and An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

9. The controller according to claim 8, characterized in that: The operation also includes: When the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions exceeds the upper threshold, one or more wind turbines operating under low wind or no wind conditions are deactivated.

10. The controller according to claim 8, characterized in that: The operation of controlling the operational state of the one or more wind turbines based at least in part on the one or more control signals further comprises: determining, by the controller based at least in part on the one or more of the sensor signals, one or more wind turbines that are deactivated and positioned in low wind or no wind conditions; One or more of the deactivated wind turbines are activated when the reactive power capability of the one or more wind turbines operating under low wind or no wind conditions is less than the lower threshold.

11. The controller according to claim 8, characterized in that: The operation also includes: identifying, by the controller, an operational runtime for each of the one or more wind turbines, wherein the operational runtime is a period of time during which the one or more wind turbines are in operation to provide reactive power or real power to the power grid; and The operational state of one or more wind turbines is controlled based at least in part on the operational runtime of the one or more of the wind turbines.

12. The controller according to claim 8, characterized in that: The operation also includes: comparing, by the controller, the reactive power capability of the one or more wind turbines to the upper threshold; comparing, by the controller, the reactive power capability of the one or more wind turbines with the lower threshold when the reactive power capability of the one or more wind turbines is less than the upper threshold; generating, by the controller, one or more control signals when the reactive power capability of the one or more wind turbines is less than the lower threshold; and The operating state of one or more wind turbines is controlled based at least in part on the one or more control signals such that one or more of the wind turbines are activated and placed in an operating state such that the one or more wind turbines provide reactive power capability to the power grid.

13. The controller according to claim 8, characterized in that: The operation also includes: identifying, by the controller, a non-operational time period for each of the one or more wind turbines, wherein the non-operational time period is a time period during which the one or more wind turbines are unable to provide reactive power or real power to the power grid; and The operational state of one or more wind turbines is controlled based at least in part on the non-operational time period.

14. A wind farm, comprising: one or more wind turbines electrically connected to an electric power grid via an interconnection point; A controller configured to perform one or more operations, the one or more operations comprising: receiving, by the controller, one or more signals from sensors, the one or more signals associated with the one or more wind turbines; determining, by the controller, one or more wind turbines operating in low wind or no wind operating conditions based at least in part on the one or more of the sensor signals; determining, by the controller, reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions; determining, by the controller, one or more thresholds based at least in part on a level of reactive power required at the point of interconnection; identifying, by the controller, a distance between each of the one or more wind turbines and the point of interconnection; comparing, by the controller, the reactive power capabilities of the one or more wind turbines operating in low wind or no wind conditions to the one or more thresholds, wherein the one or more thresholds are based at least in part on a hysteresis window associated with the reactive power requirement at the point of interconnection, and wherein the one or more thresholds include at least an upper threshold and a lower threshold; generating, by the controller, the one or more control signals based at least in part on the reactive power capability of the one or more wind turbines operating in low wind or no wind conditions, the comparison of the reactive power capability to the one or more threshold values, and the distance between each of the one or more wind turbines and the point of interconnection; and An operational state of the one or more wind turbines is controlled based at least in part on the one or more control signals.

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