System and method for power setpoint control of hybrid power generation facility

Abstract

A power generation system is provided. The power generation system includes a power generation asset configured to supply power to a power grid. The power generation asset includes at least one power generation device and at least one energy storage device coupled to the at least one power generation device. The power generation system also includes a controller communicatively coupled with the power generation asset. The controller is configured to measure a current power output of the at least one power generating device. The controller is further configured to predict a future power output of the at least one power generating device at a future point in time. The controller is further configured to determine a target power setpoint based on the current power output and the predicted future power output.

Description

CROSS-REFERENCE TO RELATED APPLICATIONS

[0001] This application claims priority to U.S. Patent Application No. 17 / 726,025, filed on April 21, 2022, the entire contents of which are hereby incorporated by reference herein. Background Art

[0002] The field of the invention relates generally to control systems for power generation facilities, and more particularly, to power set point control for hybrid power generation facilities.

[0003] A renewable power generation facility or "farm" includes a group of power generation assets (e.g., wind turbines, solar cells, etc.) and is used to supply power to a power grid. Due to the intermittent nature of renewable power (where the power generation capacity of the renewable power generation assets may vary over time), energy storage devices such as batteries are used to ensure that power can be exported to the grid at a controlled set point. For example, the set point can be adjusted based on the available renewable power generation.

[0004] Typically, when the power set point does not match the renewable power currently being generated by the power storage device, the energy storage device will charge (e.g., when the renewable power generation is greater than the power set point) or discharge (e.g., when the renewable power generation is less than the power set point). This change in state of charge may fatigue the energy storage devices and reduce their operating life.

[0005] For example, in some known systems, a set point may be adjusted using "ramping." That is, rather than changing the set point immediately, the set point may be gradually adjusted to another power value. Typically, the state of charge of the energy storage device changes during this process because, for a period of time during the ramping, there may be a mismatch between the renewable power generated and the power output of the asset. As a result, power generating assets utilizing ramping require higher capacity energy storage, and the energy storage device may experience increased fatigue.

[0006] Therefore, a power generation system capable of reducing such changes in the state of charge is desired. Summary of the invention

[0007] In one aspect, a power generation system is provided. The power generation system includes a power generation asset configured to supply power to a power grid. The power generation asset includes at least one power generation device and at least one energy storage device coupled to the at least one power generation device. The power generation system also includes a controller communicatively coupled to the power generation asset. The controller is configured to measure a current power output of the at least one power generation device. The controller is further configured to predict a future power output of the at least one power generation device at a future point in time. The controller is further configured to determine a target power set point based on the current power output and the predicted future power output.

[0008] In another aspect, a method for controlling a power generation system is provided. The power generation system includes a power generation asset configured to supply power to a power grid. The power generation asset includes at least one power generation device and at least one energy storage device coupled to the at least one power generation device. The power generation system also includes a controller communicatively coupled to the power generation asset. The method includes measuring, by the controller, a current power output of the at least one power generation device. The method also includes predicting, by the controller, a future power output of the at least one power generation device at a future point in time. The method also includes determining, by the controller, a target power set point based on the current power output and the predicted future power output.

[0009] In another aspect, a controller for a power generation system is provided. The power generation system is communicatively coupled to the controller and includes a power generation asset configured to supply power to a power grid. The power generation asset includes at least one power generation device and at least one energy storage device coupled to the at least one power generation device. The controller is configured to measure a current power output of the at least one power generation device. The controller is further configured to predict a future power output of the at least one power generation device at a future point in time. The controller is further configured to determine a target power set point based on the current power output and the predicted future power output. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] These and other features, aspects and advantages of the present disclosure will become better understood when the following detailed description is read with reference to the accompanying drawings, in which like characters represent like parts throughout the drawings, and in which:

[0011] Figure 1 is a block diagram of an example control system.

[0012] Figure 2 yes Figure 1 Another block diagram of an example control system illustrated in .

[0013] Figure 3A is a graph illustrating power generation over time as total power generation ramps following a reduction in renewable power generation.

[0014] Figure 3B is a graph illustrating power generation over time as total power generation ramps ahead of a reduction in renewable power generation.

[0015] Figure 4A is a graph illustrating power generation over time during a fault event.

[0016] Figure 4B is a graph illustrating power generation over time during a fault event, wherein power generation is adjusted to account for the fault event.

[0017] Figure 5 is a flow chart of an example method for controlling a power generation system. DETAILED DESCRIPTION

[0018] In the following description and claims, reference will be made to a number of terms which will be defined to have the following meanings.

[0019] The singular forms "a," "an," and "the" include plural references unless the context clearly dictates otherwise.

[0020] Approximate language as used throughout the specification and claims herein may be applied to modify any quantitative representation that is permitted to vary without causing a change in the basic function to which it is associated. Therefore, values ​​modified by one or more terms (e.g., "approximately," "substantially," and "approximately") are not limited to the precise values ​​specified. In at least some instances, approximate language may correspond to the precision of the instrument used to measure the value. Here and throughout the specification and claims, range limitations may be combined and / or interchanged, such ranges being identified and including all subranges contained therein unless otherwise indicated by context or language.

[0021] Embodiments described herein include a power generation system. The power generation system includes a power generation asset configured to supply power to a power grid. The power generation asset includes at least one power generation device and at least one energy storage device coupled to the at least one power generation device. The power generation system also includes a controller communicatively coupled to the power generation asset.

[0022] The controller is configured to measure the current power output of the at least one power generating device and predict the future power output of the at least one power generating device at a future point in time. The controller is also configured to determine a target power set point based on the measured current power output and the predicted future power output. By using both current feedback and predictive analysis, the matching of the power set point and the power generated by the power generating device can be improved over time, thereby reducing changes in the state of charge of the energy storage device. In addition, in some embodiments, historical analysis is used, for example, to detect system faults, which can further improve the ability of the controller to accurately determine a power set point corresponding to the actual power generated by the power generating device.

[0023] In some embodiments, the controller is further configured to ramp a current power set point of the power generating asset toward a target power set point before a future time point, wherein the current power set point reaches the target power set point after the future time point. By initiating the ramping before a change in power generation at the future time point, changes in the state of charge of the energy storage device may be reduced, thereby incurring less costs associated with capacity demands and wear on the energy storage device.

[0024] In some embodiments, the controller is further configured to detect a fault condition (e.g., a communication fault) that causes the current reported power output from the power generation asset to differ from the actual power output from the power generation asset, such as by determining that the state of charge of the energy storage device falls outside a threshold range. The controller may further adjust the current power set point in response to detection of the fault condition. This may further reduce changes in the state of charge of the energy storage device.

[0025] Figure 1 is a block diagram illustrating an example power generation system 100. The power generation system 100 includes a controller 102 and at least one of a plurality of power generation assets 104 configured to supply power to a power grid 106. The controller 102 controls operating parameters of the power generation assets 104, such as, for example, a power production set point. Such control may be based on closed-loop feedback from the power grid 106, or from other factors, as described in further detail below.

[0026] The power generation asset 104 includes at least a power generation device 108, which may be, for example, a wind turbine, a solar cell, and / or another renewable power source. The power generation asset 104 also includes an energy storage device 110, such as a battery, which is configured to temporarily store energy provided by the power generation device 108 by charging in response to receiving power from the power generation device 108 and discharging to output the stored power. The power generation asset 104 also includes a power converter 112, which is configured to convert power output by the power generation device 108 (e.g., direct current (DC) power of a first voltage) into power suitable for storage in the energy storage device 110 (e.g., DC power of a second voltage), and to convert power output by the energy storage device 110 into power suitable for supply to the power grid 106 (e.g., alternating current (AC) power).

[0027] The power converter 112 operates under the control of the controller 102 so that power can be output from the power grid 106 at a set point requested by the controller 102. If the power set point is less than the power currently produced by the power generation device 108, energy will be accumulated in the energy storage device 110, and if the power set point is greater than the power currently produced by the power generation device 108, the energy storage device 110 will be discharged. As described in further detail below, the controller 102 is configured to adjust the set point based on the current power generation of the power generation device 108 and based on the predicted future power generation of the power generation device 108.

[0028] In some embodiments, when the power set point is adjusted, the controller 102 may ramp or gradually change the set point rather than immediately changing the set point. The ramping may occur at a specified ramp rate that is defined by a specific change in power generation over time. Thus, the time required for the ramping adjustment to the power set point to occur depends on the ramp rate and the magnitude of the power adjustment.

[0029] refer to Figure 2 , the controller 102 includes a forecasting and prediction module 202, a current condition and event processing module 204, a fault handling and maintenance module 206, a weighting and set point generation module 208, a closed-loop control module 210 and a power distribution module 212, which can each be implemented using hardware, software and / or a combination thereof, for example by using a processor to execute computer executable instructions stored on a memory device.

[0030] The prediction module 202 is configured to predict future power output at a future point in time. For example, the prediction module 202 may identify a forecast of all variable power generation in the power generation for the next few minutes. If the power generated by the power generation device 108 is expected to change, the prediction module 202 may determine a new power set point based on the predicted power output.

[0031] In some embodiments, the controller 102 is configured to begin ramping the power set point before the time point occurs based on the output of the prediction module 202. For example, the prediction module 202 may predict that the power output of the power generation device 108 will drop to a lower level at time t. Before time t, the controller 102 begins to ramp down the power set point of the power generation asset 104, for example, at a substantially constant ramp rate. Before time t, power will accumulate in the energy storage device 110, and after time t and before the ramp is completed, power will be dissipated from the energy storage device 110. Assuming that the predicted change in power production of the power generation device 108 is correct and time t occurs approximately halfway through the entire ramp, the net change in the state of charge of the energy storage device 110 is close to zero. Similarly, if the prediction module 202 predicts that the power output of the power generation device 108 will increase at time t, the energy storage device 110 will be discharged during the ramp before time t and recharged during the ramp after time t for a net change in charge that is close to zero.

[0032] The current condition and event processing module 204 is configured to adjust the power set point in response to the current power output of the power generation device 108. For example, the current condition and event processing module 204 may measure the current power output of the power generation device 104 or receive a measurement of the current power output of the power generation device 104 and determine the set point based on the measured current power output. By adjusting the power set point to match the current power output of the power generation device 108, the charging rate of the energy storage device 110 is minimized because the net inflow of power from the power generation device 108 to the system is equal to the power outflow to the grid.

[0033] The fault handling and maintenance module 206 is configured to adjust the set point to maintain the state of charge range of the energy storage device 110. For example, a communication failure may occur within the power generation asset 104, wherein the power output of the power generation device 108 is misdetected or misreported, which may be a mismatch between the power output and the current set point performed by the power generation device 108. This mismatch may result in a change in the state of charge of the energy storage device 110, for example, accumulating charging if the power output by the power generation device 108 exceeds the power set point, or discharging if the power output by the power generation device 108 is less than the operating set point. If the state of charge of the energy storage device 110 thus falls outside the predefined range, the controller 102 is configured to adjust the power set point to compensate for this mismatch. For example, if the controller 102 detects that the state of charge of the energy storage device 110 is too low (to low), the controller 102 is configured to determine that the power set point is greater than the actual power output of the power generation device 108, and adjust the set point lower accordingly.

[0034] The weighted and setpoint generation module 208 is configured to determine the power setpoint and ramp rate based on inputs from the forecasting and prediction module 202, the current condition and event processing module 204, and the fault handling and maintenance module 206. In some embodiments, the weighted and setpoint module 208 determines the setpoint by one or more of fixed or dynamic weighting of the setpoints, cost function optimization, rule-based selection, priority-based selection, constraint-based limiting, and / or simple summation of the setpoints.

[0035] The closed-loop control module 210 generates control signals for one or more power generating assets 104 based on the closed-loop feedback from the power generating assets 104 and the determined power setpoints. The power distribution module 212 transmits the corresponding control signals to the one or more power generating assets 104.

[0036] Figure 3A is a graph 300 of power generation over time as total power generation ramps following a reduction in renewable power generation, and Figure 3B is a graph 302 of power generation over time when total power generation is ramped ahead of a reduction in renewable power generation, as described with respect to the forecasting and prediction module 202 ( Figure 2 Graphs 300 and 302 each have a horizontal axis 304 representing elapsed time and a vertical axis 306 representing power generation. Graphs 300 and 302 each have a power generation curve 308 representing, for example, power generation device 108 ( Figure 1 Graphs 300 and 302 each also have corresponding total facility generation curves 310 and 312 that represent power set points for power generation assets 104. Power generation curve 308 indicates a decrease in power output of power generation device 108 at time point 314.

[0037] In graph 300, as shown by total facility generation curve 310, the ramping of the power set point occurs after time point 314. Therefore, for a period of time after time point 314, energy storage device 110 is discharged, resulting in a net loss of charge. In graph 302, as shown by total facility generation curve 310, the ramping is initiated before time point 314, for example, in response to a prediction by forecast and prediction module 202 that power output will decrease. Before time point 314, energy storage device 110 is discharged when the ramped power set point is less than the power production indicated by power production curve 308, and after time point 314, when the ramped power set point is greater than the power indicated by power production curve 308, energy storage device 110 is recharged, resulting in a net change in the charge of energy storage device 110 that is close to zero.

[0038] Figure 4A is a graph 400 of power generation over time during a fault event. Figure 4B is a graph 402 of power generation over time during a fault event, wherein power generation is adjusted to account for the fault handling and maintenance module 206 ( Figure 2 Graphs 400 and 402 each have a horizontal axis 404 representing elapsed time and a horizontal axis 406 representing power generation. Graphs 400 and 402 each have a renewable generation curve 408 representing, for example, power generation device 108 ( Figure 1 Graphs 400 and 402 each also have corresponding total facility generation curves 410 and 412 that represent power set points for power generating assets 104.

[0039] like Figure 4A As shown in , if a communication failure occurs, the reported power generation may be different from the actual power generation, which causes the power set point (indicated by the total facility generation curve 410) to be higher than the actual renewable power generated (indicated by the renewable generation curve 408). This situation results in the discharge of the energy storage device 110. Figure 4B As shown in , based on the detection of a communication fault by the fault handling and maintenance module 206, the power set point (indicated by the total facility generation curve 412) is adjusted to be consistent with the actual renewable power generated (indicated by the renewable generation curve 408), which can reduce or eliminate changes in the charging state of the energy storage device 110.

[0040] Figure 5 is a flow chart illustrating an example method 500 for controlling a power generation system. In some embodiments, the method 500 is performed by a power generation system (e.g., Figure 1 and Figure 2 The power generation system 100 shown in FIG. 1 is implemented, for example, using a controller 102 .

[0041] The method 500 includes measuring 502, by a controller, a current power output of at least one power generating device, such as the power generating device 108. The method 500 also includes predicting 504, by the controller, a future power output of the at least one power generating device at a future point in time. The method 500 also includes determining 506, by the controller, a target power set point based on the current power output and the predicted future power output.

[0042] In some embodiments, method 500 further includes, before the future time point, ramping, by the controller, a current power set point of the power generating asset toward a target set point, wherein the current power set point reaches the target power set point after the future time point. In some such embodiments, method 500 further includes selecting, by the controller, a ramping ramp rate at which to ramp the current power set point. In some such embodiments, selecting the ramp rate includes selecting, by the controller, a ramp rate that reduces a change in a state of charge of at least one energy storage device (e.g., energy storage device 110).

[0043] In certain embodiments, the method 500 further includes detecting, by the controller, a fault condition that causes a currently reported power output from the power generating asset to differ from an actual power output from the power generating asset, and adjusting, by the controller, a current power set point in response to the detection of the fault condition. In some such embodiments, detecting the fault condition includes detecting, by the controller, the fault condition based on determining that a state of charge of the energy storage device is outside of a threshold range. In certain such embodiments, adjusting the current power set point includes adjusting, by the controller, the current power set point to reduce a change in the state of charge of the at least one energy storage device.

[0044] In some embodiments, at least one energy storage device includes a battery.

[0045] In certain embodiments, the power generation system further includes a plurality of power generation assets (eg, power generation assets 104 ), and the method 500 further includes determining, by the controller, a respective power setpoint for each of the plurality of power generation assets.

[0046] Example technical effects of the methods, systems, and apparatus described herein include at least one of: (a) reducing charging capacity requirements for energy storage devices used in renewable power generation facilities by reducing changes in the state of charge that occur due to changes in renewable power generation; and (b) reducing fatigue caused by changes in the state of charge of energy storage devices used in renewable power generation facilities by reducing changes in the state of charge that occur due to changes in renewable power generation.

[0047] Example embodiments of power generation systems are provided herein. Systems and methods of operating and manufacturing such systems and devices are not limited to the specific embodiments described herein, but rather, components of the systems and / or steps of the methods may be utilized independently of and separately from other components and / or steps described herein. For example, the methods may also be used in conjunction with other electronic systems and are not limited to practice with only the electronic systems and methods as described herein. Rather, the example embodiments may be implemented and utilized in conjunction with many other electronic systems.

[0048] Some embodiments relate to the use of one or more electronic or computing devices.Such devices generally include processors, processing devices, or controllers, such as general-purpose central processing units (CPUs), graphics processing units (GPUs), microcontrollers, reduced instruction set computers (RISC) processors, application-specific integrated circuits (ASICs), programmable logic circuits (PLCs), field programmable gate arrays (FPGAs), digital signal processing (DSP) devices, and / or any other circuits or processing devices capable of performing the functions described herein. The methods described herein may be encoded as executable instructions embodied in a computer-readable medium, which includes, but is not limited to, storage devices and / or memory devices. When executed by a processing device, such instructions cause the processing device to perform at least a portion of the methods described herein. The above embodiments are examples only, and are therefore not intended to limit the definition and / or meaning of the terms processor and processing device in any way.

[0049] Although specific features of various embodiments of the present disclosure may be shown in some drawings and not in other drawings, this is only for convenience. According to the principles of the present disclosure, any feature of the drawings may be referenced and / or claimed in combination with any feature of any other drawings.

[0050] This written description uses examples, including the best mode, to disclose the invention, and also enables any person skilled in the art to practice the invention, including making and using any device or system and performing any combined method. The patentable scope of the invention is defined by the claims, and may include other examples that occur to those skilled in the art. Such other examples are intended to be within the scope of the claims if they have structural elements that do not differ from the literal language of the claims, or if they include equivalent structural elements that do not differ substantially from the literal language of the claims.

Claims

1. A power generation system comprising: a power generating asset configured to supply power to a power grid, the power generating asset comprising at least one power generating device and at least one energy storage device coupled to the at least one power generating device; a controller communicatively coupled to the power generating asset, the controller being configured to: measuring a current power output of the at least one power generating device; predicting a future power output of the at least one power generating device at a future point in time; as well as A target power set point is determined based on the current power output and the predicted future power output.

2. The power generation system according to claim 1, wherein: The controller is further configured to ramp a current power set point of the power generating asset toward the target power set point before the future time point, wherein the current power set point reaches the target power set point after the future time point.

3. The power generation system according to claim 2, wherein: The controller is further configured to select a ramp rate at which to ramp the current power set point.

4. The power generation system according to claim 3, wherein: To select the ramp rate, the controller is configured to select a ramp rate that reduces a change in the state of charge of the at least one energy storage device.

5. The power generation system according to claim 1, wherein: The controller is also configured to: detecting a fault condition that causes a currently reported power output from the power generating asset to be different than an actual power output from the power generating asset; and In response to the detection of the fault condition, the current power set point is adjusted.

6. The power generation system according to claim 5, wherein: To detect the fault condition, the controller is configured to detect the fault condition based on determining that a state of charge of the energy storage device is outside of a threshold range.

7. The power generation system according to claim 6, wherein: To adjust the current power set point, the controller is configured to adjust the current power set point to reduce a change in a state of charge of the at least one energy storage device.

8. The power generation system of claim 1, wherein: The at least one energy storage device comprises a battery.

9. The power generation system of claim 1, further comprising a plurality of power generating assets, wherein the controller is configured to determine a respective power set point for each of the plurality of power generating assets.

10. A method for controlling a power generation system, the power generation system comprising a power generation asset configured to supply power to a power grid, the power generation asset comprising at least one power generation device and at least one energy storage device coupled to the at least one power generation device, the power generation system further comprising a controller communicatively coupled to the power generation asset, the method comprising measuring, by the controller, a current power output of the at least one power generating device; predicting, by the controller, a future power output of the at least one power generating device at a future point in time; as well as A target power set point is determined by the controller based on the current power output and the predicted future power output.

11. The method of claim 10, further comprising, prior to the future time point, ramping, by the controller, a current power set point of the power generating asset toward the target power set point, wherein The current power set point reaches the target power set point after the future time point.

12. The method of claim 11, further comprising selecting, by the controller, a ramp rate at which the current power set point is ramped.

13. The method according to claim 12, wherein: Selecting the ramp rate includes selecting, by the controller, a ramp rate that reduces a change in the state of charge of the at least one energy storage device.

14. The method according to claim 10, further comprising: detecting, by the controller, a fault condition that causes a currently reported power output from the power generating asset to differ from an actual power output from the power generating asset; as well as The current power set point is adjusted, by the controller, in response to the detection of the fault condition.

15. The method according to claim 14, wherein: Detecting the fault condition includes detecting, by the controller, the fault condition based on determining that a state of charge of the energy storage device is outside of a threshold range.

16. The method according to claim 15, wherein: Adjusting the present power set point includes adjusting, by the controller, the present power set point to reduce a change in a state of charge of the at least one energy storage device.

17. The method according to claim 10, wherein: The power generation system also includes a plurality of power generation assets, and wherein the method further includes determining, by the controller, a respective power set point for each of the plurality of power generation assets.

18. A controller for a power generation system, the power generation system being communicatively coupled to the controller and comprising a power generation asset configured to supply power to a power grid, the power generation asset comprising at least one power generation device and at least one energy storage device coupled to the at least one power generation device, the controller being configured to: measuring a current power output of the at least one power generating device; predicting a future power output of the at least one power generating device at a future point in time; and A target power set point is determined based on the current power output and the predicted future power output.

19. The controller of claim 18, further configured to ramp a current power set point of the at least one power generating asset toward the target power set point prior to the future time point, wherein: The current power set point reaches the target power set point after the future time point.

20. The controller of claim 19, further configured to select a ramp rate at which the current power set point is ramped.

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