Method, apparatus, storage medium and processor for controlling grid operating frequency

Abstract

Embodiments of the present application provide a method, device, storage medium and processor for controlling the operating frequency of a power grid. The method comprises: for each wind turbine in the power grid, obtaining the current wind speed of the wind turbine and the current frequency of the power grid when the wind turbine is in a preset operating state; determining the current power and the current tip speed of the wind turbine according to a first historical power and a first historical rotating speed corresponding to the current wind speed in the kinetic energy storage curve of the wind turbine; determining the frequency difference between the first preset frequency and the current frequency when the current frequency is less than the first preset frequency, and determining the power increment of the wind turbine under the frequency difference; determining the target tip speed of the wind turbine according to the power increment, the current power and the current wind speed; and controlling each wind turbine to operate from the current tip speed to the corresponding target tip speed, so as to convert the kinetic energy released by the operation of each wind turbine into electrical energy, to adjust the operating frequency of the power grid, to quickly support the frequency of the power grid, and to save the cost of adding energy storage facilities.

Description

Technical Field

[0001] This application relates to the field of power grid technology, and more specifically to a method, apparatus, storage medium, and processor for controlling the operating frequency of a power grid. Background Technology

[0002] With the increasing penetration of new energy sources, the randomness of power output and lack of inertia support in wind farms pose challenges to the safe and stable operation of new power systems. Therefore, frequency regulation retrofitting of wind farms is necessary. Inertia response control can be employed during this retrofit. When the frequency of the power grid where the wind farm is located changes, the wind turbines in the wind farm can reduce the rate of change of the grid frequency and improve the frequency floor value. However, inertia response control must have a short response time, and when the grid frequency drops, the wind turbines need to increase their output to support the grid frequency.

[0003] Currently, besides allowing renewable wind farms to operate at reduced load to provide backup primary frequency regulation energy to support the grid frequency, energy storage facilities can also be used as an energy source to support the grid frequency. However, the above methods are difficult to support the grid frequency in a short period of time, and the reduced load operation of wind farms will greatly reduce the operating economic efficiency of wind turbines in renewable wind farms. Using energy storage facilities to provide frequency support for the grid requires the installation of additional energy storage facilities, which results in excessively high infrastructure construction costs. Summary of the Invention

[0004] The purpose of this application is to provide a method, apparatus, storage medium, and processor for controlling the operating frequency of a power grid, so as to solve the problem of excessively high facility construction costs required for power grid operating frequency control in the prior art.

[0005] To achieve the above objectives, the first aspect of this application provides a method for controlling the operating frequency of a power grid, comprising:

[0006] For each wind turbine in the power grid, under the condition that the wind turbine is in a preset operating state, the current wind speed of the wind turbine and the current frequency of the power grid are obtained;

[0007] The current power and current blade tip speed of the wind turbine are determined based on the first historical power and the first historical speed corresponding to the current wind speed in the kinetic energy storage curve of the wind turbine.

[0008] If the current frequency is less than the first preset frequency, determine the frequency difference between the first preset frequency and the current frequency, and determine the power increment of the fan under the frequency difference.

[0009] The target tip speed of the wind turbine is determined based on the power increment, the current power, and the current wind speed.

[0010] Each wind turbine is controlled to operate from its current tip speed to its corresponding target tip speed, so that the kinetic energy released by each wind turbine is converted into electrical energy to adjust the operating frequency of the power grid.

[0011] In this embodiment of the application, determining the target blade tip speed of the wind turbine based on the power increment, the current power, and the current wind speed includes: obtaining the second historical power and the second historical speed corresponding to the current wind speed in the kinetic energy release curve of the wind turbine; determining the target power of the wind turbine based on the power increment, the current power, and the second historical power; determining at least one candidate blade tip speed corresponding to the target power, wherein each candidate blade tip speed is greater than the second historical speed and less than the first historical speed; and determining the largest candidate blade tip speed among all candidate blade tip speeds as the target blade tip speed.

[0012] In this embodiment of the application, the method further includes: for each wind turbine in the power grid, obtaining multiple historical tip speeds of the wind turbine at each historical wind turbine wind speed; for each historical wind turbine wind speed, determining the optimal tip speed ratio of the wind turbine at the historical wind turbine wind speed based on the historical wind turbine wind speed and the corresponding multiple historical tip speeds; for each historical wind turbine wind speed, determining the optimal power and optimal speed of the wind turbine corresponding to the optimal tip speed ratio at the historical wind turbine wind speed; generating an ideal power curve of the wind turbine based on the optimal power and optimal speed of the wind turbine at each historical wind turbine wind speed; and determining a kinetic energy storage curve and a kinetic energy release curve based on the ideal power curve.

[0013] In this embodiment, determining the kinetic energy storage curve and the kinetic energy release curve based on the ideal power curve includes: for each historical wind turbine speed, determining the historical power at the historical wind turbine speed by multiplying a preset coefficient by the optimal power of the wind turbine at the historical wind turbine speed; determining the historical blade tip speed corresponding to the historical power as the undetermined speed at the historical wind turbine speed; determining the undetermined speeds that are greater than and less than the optimal speed of the wind turbine as the first historical speed and the second historical speed at the historical wind turbine speed, respectively; generating the kinetic energy storage curve based on the historical power and the first historical speed at each historical wind turbine speed; and generating the kinetic energy release curve based on the historical power and the second historical speed at each historical wind turbine speed.

[0014] In this embodiment of the application, the method further includes: during the operation of each wind turbine at the corresponding target blade tip speed, determining whether the adjusted operating frequency is less than the first preset frequency; if the adjusted operating frequency is less than the first preset frequency, taking the adjusted operating frequency as the current frequency, and returning to the step of determining the frequency difference between the first preset frequency and the current frequency, so as to readjust the operating frequency of the power grid.

[0015] In this embodiment of the application, the method further includes: when the adjusted operating frequency is greater than or equal to the first preset frequency and less than the second preset frequency, controlling each fan to run from the target blade tip speed to the fan's optimal speed or the current blade tip speed at the current wind speed.

[0016] In this embodiment of the application, the method further includes: determining the operating state of the power grid as a frequency under-disturbance state when the current frequency is less than a first preset frequency; and determining the operating state of the power grid as a normal operating state when the current frequency is greater than the first preset frequency and less than the second preset frequency.

[0017] A second aspect of this application provides an apparatus for controlling the operating frequency of a power grid, comprising:

[0018] The memory is configured to store instructions; and

[0019] The processor is configured to retrieve instructions from memory and, when executing the instructions, to implement the aforementioned method for controlling the operating frequency of the power grid.

[0020] A third aspect of this application provides a machine-readable storage medium storing instructions that, when executed by a processor, configure the processor to perform the aforementioned method for controlling the operating frequency of a power grid.

[0021] A fourth aspect of this application provides a processor configured to perform the above-described method for controlling the operating frequency of a power grid.

[0022] Through the above technical solution, when the operating frequency of the power grid is lower than the first preset frequency, that is, when the power grid frequency drops, the kinetic energy of the wind turbine itself can be released quickly by adjusting the blade tip speed of the wind turbine, thereby quickly supporting the power grid frequency. There is no need to build additional energy storage facilities, saving the facility construction costs incurred by adding energy storage facilities. The wind farm where the wind turbine is located also does not need to operate at reduced load, greatly ensuring the economic benefits of wind turbine operation.

[0023] Other features and advantages of the embodiments of this application will be described in detail in the following detailed description section. Attached Figure Description

[0024] The accompanying drawings are provided to further illustrate the embodiments of this application and form part of the specification. They are used together with the following detailed description to explain the embodiments of this application, but do not constitute a limitation on the embodiments of this application. In the drawings:

[0025] Figure 1 A schematic flowchart of a method for controlling the operating frequency of a power grid according to an embodiment of this application is shown.

[0026] Figure 2The diagram illustrates the wind power characteristic curve and operating curve of a 5MW doubly-fed asynchronous generator set according to an embodiment of this application.

[0027] Figure 3 A schematic flowchart of a method for controlling the operating frequency of a power grid according to another embodiment of this application is shown.

[0028] Figure 4 The diagram illustrates the internal structure of a computer device according to an embodiment of this application. Detailed Implementation

[0029] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. It should be understood that the specific embodiments described herein are only for illustration and explanation of the embodiments of this application and are not intended to limit the embodiments of this application. All other embodiments obtained by those skilled in the art based on the embodiments of this application without creative effort are within the scope of protection of this application.

[0030] It should be noted that if the embodiments of this application involve directional indicators (such as up, down, left, right, front, back, etc.), the directional indicators are only used to explain the relative positional relationship and movement of the components in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indicators will also change accordingly.

[0031] Furthermore, if the embodiments of this application involve descriptions such as "first" or "second," these descriptions are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Therefore, features defined with "first" or "second" may explicitly or implicitly include at least one of those features. Additionally, the technical solutions of various embodiments can be combined with each other, but this must be based on the ability of those skilled in the art to implement them. If the combination of technical solutions is contradictory or impossible to implement, it should be considered that such a combination of technical solutions does not exist and is not within the scope of protection claimed in this application.

[0032] Figure 1 A schematic flowchart illustrating a method for controlling the operating frequency of a power grid according to an embodiment of this application is shown. Figure 1 As shown in one embodiment of this application, a method for controlling the operating frequency of a power grid is provided, comprising the following steps:

[0033] Step 101: For each wind turbine in the power grid, under the condition that the wind turbine is in the preset operating state, obtain the current wind speed of the wind turbine and the current frequency of the power grid.

[0034] The power grid may include multiple wind turbine units, and each wind turbine unit may include multiple wind turbines. The operating state of a wind turbine may include KES state (kinetic energy storage state), KER state (kinetic energy release state), and MPPT state (kinetic energy steady state). For each wind turbine in the power grid, when the turbine is in a preset operating state, the processor can obtain the current wind speed of the turbine and the current frequency of the power grid. The preset operating state refers to the KES state. The current wind speed specifically refers to the air speed at the tip of the turbine blades.

[0035] Step 102: Determine the current power and current blade tip speed of the wind turbine based on the first historical power and first historical speed corresponding to the current wind speed in the kinetic energy storage curve of the wind turbine.

[0036] The kinetic energy storage curve refers to the KES curve. When the wind turbine is operating in KES state (kinetic energy storage state), it can be determined that it is operating along the KES curve (kinetic energy storage curve). The processor can determine the wind turbine's current power and current blade tip speed based on the first historical power and first historical speed corresponding to the current wind speed in the kinetic energy storage curve. Specifically, when the wind turbine is in a preset operating state, the current power is the first historical power corresponding to the current wind speed, and the current blade tip speed is the first historical speed corresponding to the current wind speed.

[0037] Step 103: When the current frequency is less than the first preset frequency, determine the frequency difference between the first preset frequency and the current frequency, and determine the power increment of the fan under the frequency difference.

[0038] When the current frequency of the power grid is greater than a first preset frequency, the processor can determine the frequency difference between the first preset frequency and the current frequency, and then determine the power increment of the wind turbine under the frequency difference. The first preset frequency can be customized according to actual conditions. For example, the first preset frequency can be f... L It means that f L =50Hz-f D Among them, f DThis refers to frequency error, which can be adjusted appropriately according to actual needs. In one embodiment, when determining the power increment of the fan under a frequency difference, a lookup table between frequency difference and power increment can be obtained first, and then the lookup table can be traversed according to the determined frequency difference. If a preset frequency difference corresponding to the frequency difference exists in the lookup table, the preset power increment corresponding to the preset frequency difference can be determined as the corresponding power increment. If no preset frequency difference corresponding to the frequency difference exists in the lookup table, the minimum preset frequency difference greater than the frequency difference and the maximum preset frequency difference less than the frequency difference can be determined. Then, the average of the preset power increment corresponding to the minimum preset frequency difference and the preset power increment corresponding to the maximum preset frequency difference can be determined as the power increment corresponding to the frequency difference.

[0039] In this embodiment of the application, the method further includes: determining the operating state of the power grid as a frequency under-disturbance state when the current frequency is less than a first preset frequency; and determining the operating state of the power grid as a normal operating state when the current frequency is greater than the first preset frequency and less than the second preset frequency.

[0040] When the current frequency is lower than a first preset frequency, the processor can determine that the power grid is operating in a frequency downsampling state, where the power grid frequency drops. When the current frequency is higher than the first preset frequency but lower than a second preset frequency, the processor can determine that the power grid is operating in a normal operating state. When the current frequency is higher than the second preset frequency, the processor can determine that the power grid is operating in a frequency upsampling state. The second preset frequency can be customized according to actual conditions. For example, the second preset frequency can be f... H It means that f H =50Hz+f D Among them, f D This refers to frequency error, which can be adjusted appropriately according to actual needs.

[0041] Step 104: Determine the target blade tip speed of the fan based on the power increment, current power, and current wind speed.

[0042] The processor can determine the target tip speed of the fan based on the fan's current power, current wind speed, and power increment at the frequency difference.

[0043] In this embodiment of the application, determining the target blade tip speed of the wind turbine based on the power increment, the current power, and the current wind speed includes: obtaining the second historical power and the second historical speed corresponding to the current wind speed in the kinetic energy release curve of the wind turbine; determining the target power of the wind turbine based on the power increment, the current power, and the second historical power; determining at least one candidate blade tip speed corresponding to the target power, wherein each candidate blade tip speed is greater than the second historical speed and less than the first historical speed; and determining the largest candidate blade tip speed among all candidate blade tip speeds as the target blade tip speed.

[0044] The kinetic energy release curve refers to the KER curve. When the wind turbine operates within the KER curve, its corresponding operating state is the KER state. The processor can obtain the second historical power and second historical speed corresponding to the current wind speed from the wind turbine's kinetic energy release curve. Then, the processor can determine the wind turbine's target power based on the power increment, the current power, and the second historical power. Specifically, the sum of the power increment and the current power can be determined, where the sum is greater than or equal to the second historical power, and this sum can be determined as the wind turbine's target power. The processor can determine at least one candidate blade tip speed corresponding to the target power, where each candidate blade tip speed is greater than the second historical speed and less than the first historical speed. The processor can determine the largest candidate blade tip speed among all candidate blade tip speeds as the target blade tip speed.

[0045] In this embodiment of the application, the method further includes: for each wind turbine in the power grid, obtaining multiple historical tip speeds of the wind turbine at each historical wind turbine wind speed; for each historical wind turbine wind speed, determining the optimal tip speed ratio of the wind turbine at the historical wind turbine wind speed based on the historical wind turbine wind speed and the corresponding multiple historical tip speeds; for each historical wind turbine wind speed, determining the optimal power and optimal speed of the wind turbine corresponding to the optimal tip speed ratio at the historical wind turbine wind speed; generating an ideal power curve of the wind turbine based on the optimal power and optimal speed of the wind turbine at each historical wind turbine wind speed; and determining a kinetic energy storage curve and a kinetic energy release curve based on the ideal power curve.

[0046] For each wind turbine in the power grid, the processor can acquire multiple historical tip speeds at each historical wind turbine speed. For each historical wind turbine speed, the optimal tip speed ratio for that historical wind turbine speed is determined based on the historical wind turbine speed and the corresponding multiple historical tip speeds. Specifically, the ratio between the historical wind turbine speed and each historical tip speed can be determined, and this ratio is defined as the tip speed ratio corresponding to that historical wind turbine speed and historical tip speed. Then, the largest tip speed ratio can be determined as the optimal tip speed ratio for that historical wind turbine speed. For each historical wind turbine speed, the processor can determine the optimal power and optimal speed of the wind turbine corresponding to the optimal tip speed ratio at that historical wind turbine speed. The processor can generate an ideal power curve for the wind turbine based on the optimal power and optimal speed for each historical wind turbine speed. The processor can then determine the kinetic energy storage curve and the kinetic energy release curve based on the ideal power curve.

[0047] In this embodiment, determining the kinetic energy storage curve and the kinetic energy release curve based on the ideal power curve includes: for each historical wind turbine speed, determining the historical power at the historical wind turbine speed by multiplying a preset coefficient by the optimal power of the wind turbine at the historical wind turbine speed; determining the historical blade tip speed corresponding to the historical power as the undetermined speed at the historical wind turbine speed; determining the undetermined speeds that are greater than and less than the optimal speed of the wind turbine as the first historical speed and the second historical speed at the historical wind turbine speed, respectively; generating the kinetic energy storage curve based on the historical power and the first historical speed at each historical wind turbine speed; and generating the kinetic energy release curve based on the historical power and the second historical speed at each historical wind turbine speed.

[0048] For each historical wind turbine speed, the processor can determine the historical power at that wind turbine speed by multiplying a preset coefficient by the optimal power of the turbine at that historical wind turbine speed. The preset coefficient can be customized based on actual conditions. For example, the preset coefficient can be selected as close to 1 as possible, with a setting range of 0.9 to 1.0. For example, a preset coefficient of 0.98 would ensure the wind turbine power is close to the optimal power, avoiding excessive reduction in wind energy utilization. The processor can determine the historical blade tip speed corresponding to the historical power as the undetermined speed at the historical wind turbine speed. The processor can determine the undetermined speeds, which are greater than and less than the optimal speed, as the first and second historical speeds at the historical wind turbine speeds, respectively. The processor can generate a kinetic energy storage curve based on the historical power and the first historical speed at each historical wind turbine speed. The processor can also generate a kinetic energy release curve based on the historical power and the second historical speed at each historical wind turbine speed.

[0049] In the embodiments of this application, the ideal power curve, kinetic energy release curve, and kinetic energy storage curve can be stored in the form of tables and piecewise functions.

[0050] like Figure 2 As shown, a wind power characteristic curve and an operation curve diagram of a 5MW doubly-fed asynchronous generator set are provided.

[0051] Rotorspeed refers to the fan's rotational speed, measured in rad / s, and Power refers to the fan's frequency, measured in MW. n This refers to the maximum power of the fan, P. n It is 5MW. ω min This refers to the minimum operating speed of the fan, ω. min = 0.762 rad / s. V W This refers to the wind speed of the wind turbine. Each wind speed corresponds to a power and speed characteristic curve, i.e., the wind power characteristic curve. MPPT refers to the ideal power curve. Wind turbine operating curves include KES and KER. KES refers to the kinetic energy storage curve, and KER refers to the kinetic energy release curve.

[0052] The intersection of the MPPT curve with the power and speed characteristic curves at each wind speed represents the optimal power and optimal speed of the wind turbine at that wind speed. The intersection of the KES curve with the power and speed characteristic curves at each wind speed represents the historical power and first historical speed of the wind turbine at that wind speed. The intersection of the KER curve with the power and speed characteristic curves at each wind speed represents the historical power and second historical speed of the wind turbine at that wind speed.

[0053] from Figure 2 From this, we can see that if P n Let P be the maximum power the fan can operate at when the wind speed is V. At this speed, the output power P will decrease regardless of whether the fan speed increases or decreases. However, the power-speed characteristic curve of the fan changes relatively smoothly near the maximum power point. Even if the speed changes significantly, the output power will not change significantly compared to the maximum point. Therefore, we can find an output power of k*P on both sides of the maximum power point of each power-speed characteristic curve of the fan. n point.

[0054] For example, for the power-speed characteristic curve with a wind speed of 9 m / s, the maximum power is the power corresponding to the intersection of this power-speed characteristic curve and the MPPT curve. If we find the output power k*P on the right side of this intersection... n Let point A be the location of the wind turbine. The wind turbine speed corresponding to point A is the first historical speed ω at that wind speed. A Find the output power k*P on its left side. n Point C is the starting point, and the corresponding fan speed at point C is the second historical speed ω at that wind speed. CAt this point, a KER curve can be constructed based on multiple C points under different wind speeds, and a KES curve can be constructed based on multiple A points under different wind speeds.

[0055] Furthermore, points A and C have the same power, but their corresponding rotational speeds are different. Therefore, there is a certain difference in rotational kinetic energy between points A and C. Specifically, taking a wind speed of 9 m / s as an example, at a wind speed of 9 m / s, the steady-state operating point of the wind turbine is the intersection of the MPPT curve and the wind power characteristic curve corresponding to 9 m / s, with a power of 2.7 MW and a rotational speed of 1.1 rad / s. If the wind turbine's rotational speed is increased to 1.22 rad / s, its output power decreases to 98% of the MPPT power, corresponding to point A as the steady-state operating point. Point A has a higher rotational speed than the MPPT operating point, while its output power decreases by only 2%. Similarly, if the wind turbine's rotational speed is reduced to 0.99 rad / s, the wind turbine will operate at point C, with an output power of 98% of the MPPT power. Point C has a lower rotational speed than the MPPT operating point, while its output power also decreases by only 2%. It can be seen that points A and C have the same output power, but these two operating points have a difference of nearly 30% in rated rotational kinetic energy (based on the kinetic energy at rated speed).

[0056] During normal operation, wind turbines typically operate within the KES curve. The turbine runs at the speed at point A. When the grid frequency drops, the turbine's operating point shifts from point A to point C, changing the turbine's speed without significantly altering its output power, which remains essentially constant and equal to the MPPT power. At this point, the rotational kinetic energy difference between point A and the shift point is released, injecting additional energy into the grid. This additional energy is sufficient to prevent a significant drop in the grid frequency. For example, with a wind speed of 9 m / s, if the grid frequency is lower than a first preset frequency, the turbine can operate... Figure 2 At point B in the diagram, the kinetic energy difference between point B and point A will be injected into the power grid to support the grid frequency.

[0057] Step 105: Control each fan to run from its current tip speed to the corresponding target tip speed, so as to convert the kinetic energy released by each fan into electrical energy, thereby adjusting the operating frequency of the power grid.

[0058] The processor can control each wind turbine to run from its current tip speed to the corresponding target tip speed, so as to convert the kinetic energy released by each wind turbine into electrical energy, thereby adjusting the operating frequency of the power grid.

[0059] In this embodiment of the application, the method further includes: during the operation of each wind turbine at the corresponding target blade tip speed, determining whether the adjusted operating frequency is less than the first preset frequency; if the adjusted operating frequency is less than the first preset frequency, taking the adjusted operating frequency as the current frequency, and returning to the step of determining the frequency difference between the first preset frequency and the current frequency, so as to readjust the operating frequency of the power grid.

[0060] During the operation of each wind turbine at its target blade tip speed, a secondary drop in grid frequency may occur, meaning the grid frequency may fall below the first preset frequency. In this case, the processor can determine whether the adjusted operating frequency is still lower than the first preset frequency. If the adjusted operating frequency is lower than the first preset frequency, the processor can use the adjusted operating frequency as the current frequency and return to the step of determining the frequency difference between the first preset frequency and the current frequency to readjust the grid operating frequency until the adjusted grid operating frequency is greater than or equal to the first preset frequency and less than the second preset frequency.

[0061] In this embodiment of the application, the method further includes: when the adjusted operating frequency is greater than or equal to the first preset frequency and less than the second preset frequency, controlling each fan to run from the target blade tip speed to the fan's optimal speed or the current blade tip speed at the current wind speed.

[0062] When the adjusted operating frequency is greater than or equal to the first preset frequency and less than the second preset frequency, the processor can control each fan to operate from the target blade tip speed to the fan's optimal speed or the current blade tip speed at the current wind speed. That is, in this case, the fan can be set to the MPPT state, which determines that it is operating on the ideal power curve, and the fan operates at its optimal speed. Alternatively, the fan can be set to the KES state, which determines that it is operating on the kinetic energy storage curve, and the fan operates at the first historical speed corresponding to the current wind speed in the kinetic energy storage curve.

[0063] like Figure 3 As shown, a flowchart illustrating another method for controlling the operating frequency of a power grid is provided.

[0064] When controlling the power grid operating frequency, the MPPT curve of the wind turbine, i.e., the ideal power curve of the wind turbine, can be determined first. Then, the k value can be determined, and the KER and KES curves can be determined based on the k value. The k value can range from 0.9 to 1.0. The k value can be customized according to actual conditions. For example, the k value can be 0.98. Next, the power grid status can be acquired in real time, and frequency support can be achieved through curve offset. The power grid operating status can be determined based on the grid voltage, current, active power, and frequency. The power grid status can include frequency down-disturbance state, frequency up-disturbance state, and normal operation state.

[0065] When the grid frequency is lower than frequency f L At this time, it can be determined that the power grid is in a frequency-disrupted state. Where f L =50Hz-f D f D This refers to frequency error, which can be customized according to actual needs. When the grid frequency is greater than frequency f... H When the frequency of the power grid is at f, it can be determined that the power grid is in a frequency disturbance state. L to f H When this period is within a certain range, it can be determined that the power grid is in normal operating condition. Where f H =50Hz-f D Curve offset refers to determining the angular velocity of a wind turbine based on the current power grid status and wind speed using piecewise functions or table lookup methods, and then using torque control to make the wind turbine actually operate at that angular velocity, ultimately enabling the wind turbine to reach the specified operating point.

[0066] Through the above technical solution, when the operating frequency of the power grid is lower than the first preset frequency, that is, when the power grid frequency drops, the kinetic energy of the wind turbine itself can be released quickly by adjusting the blade tip speed of the wind turbine, thereby quickly supporting the power grid frequency. There is no need to build additional energy storage facilities, saving the facility construction costs incurred by adding energy storage facilities. The wind farm where the wind turbine is located also does not need to operate at reduced load, greatly ensuring the economic benefits of wind turbine operation.

[0067] Figure 1 and 3 This is a flowchart illustrating a method for controlling the operating frequency of a power grid in one embodiment. It should be understood that, although... Figure 1 and 3 The steps in the flowchart are shown sequentially as indicated by the arrows, but these steps are not necessarily executed in the order indicated by the arrows. Unless otherwise explicitly stated herein, there is no strict order in which these steps are executed, and they can be performed in other orders. Figure 1 and 3 At least some of the steps in the process may include multiple sub-steps or multiple stages. These sub-steps or stages are not necessarily executed at the same time, but can be executed at different times. The execution order of these sub-steps or stages is not necessarily sequential, but can be executed in turn or alternately with other steps or at least some of the sub-steps or stages of other steps.

[0068] In one embodiment, an apparatus for controlling the operating frequency of a power grid is provided, comprising:

[0069] The memory is configured to store instructions; and

[0070] The processor is configured to retrieve instructions from memory and, when executing the instructions, to implement the aforementioned method for controlling the operating frequency of the power grid.

[0071] In one embodiment, a machine-readable storage medium is provided, on which instructions are stored, for causing a machine to perform the above-described method for controlling the operating frequency of a power grid.

[0072] In one embodiment, a processor is provided for running a program, wherein the program executes the method described above for controlling the operating frequency of the power grid.

[0073] In one embodiment, a computer device is provided, which may be a server, and its internal structure diagram may be as follows: Figure 4 As shown. The computer device includes a processor A01, a network interface A02, a memory (not shown), and a database (not shown) connected via a system bus. The processor A01 provides computing and control capabilities. The memory includes internal memory A03 and a non-volatile storage medium A04. The non-volatile storage medium A04 stores an operating system B01, a computer program B02, and a database (not shown). The internal memory A03 provides an environment for the operation of the operating system B01 and the computer program B02 stored in the non-volatile storage medium A04. The database stores data such as the target blade tip rotation speed. The network interface A02 is used for communication with external terminals via a network connection. When the computer program B02 is executed by the processor A01, it implements a method for controlling the operating frequency of the power grid.

[0074] Those skilled in the art will understand that Figure 4 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0075] This application provides a device including a processor, a memory, and a program stored in the memory and executable on the processor. When the processor executes the program, it performs the following steps: for each wind turbine in the power grid, under the condition that the wind turbine is in a preset operating state, the current wind speed of the wind turbine and the current frequency of the power grid are obtained; the current power and current blade tip speed of the wind turbine are determined according to the first historical power and the first historical rotational speed corresponding to the current wind speed in the kinetic energy storage curve of the wind turbine; if the current frequency is less than the first preset frequency, the frequency difference between the first preset frequency and the current frequency is determined, and the power increment of the wind turbine under the frequency difference is determined; the target blade tip speed of the wind turbine is determined according to the power increment, the current power, and the current wind speed; each wind turbine is controlled to run from the current blade tip speed to the corresponding target blade tip speed, so as to convert the kinetic energy released by each wind turbine into electrical energy, thereby adjusting the operating frequency of the power grid.

[0076] In one embodiment, determining the target tip speed of the wind turbine based on the power increment, the current power, and the current wind speed includes: acquiring the second historical power and the second historical speed corresponding to the current wind speed in the kinetic energy release curve of the wind turbine; determining the target power of the wind turbine based on the power increment, the current power, and the second historical power; determining at least one candidate tip speed corresponding to the target power, wherein each candidate tip speed is greater than the second historical speed and less than the first historical speed; and determining the largest candidate tip speed among all candidate tip speeds as the target tip speed.

[0077] In one embodiment, the method further includes: for each wind turbine in the power grid, acquiring multiple historical tip speeds of the wind turbine at each historical wind turbine wind speed; for each historical wind turbine wind speed, determining the optimal tip speed ratio of the wind turbine at the historical wind turbine wind speed based on the historical wind turbine wind speed and the corresponding multiple historical tip speeds; for each historical wind turbine wind speed, determining the optimal power and optimal speed of the wind turbine corresponding to the optimal tip speed ratio at the historical wind turbine wind speed; generating an ideal power curve of the wind turbine based on the optimal power and optimal speed of the wind turbine at each historical wind turbine wind speed; and determining a kinetic energy storage curve and a kinetic energy release curve based on the ideal power curve.

[0078] In one embodiment, determining the kinetic energy storage curve and the kinetic energy release curve based on the ideal power curve includes: for each historical wind turbine speed, determining the historical power at the historical wind turbine speed by multiplying a preset coefficient by the optimal power of the wind turbine at the historical wind turbine speed; determining the historical blade tip speed corresponding to the historical power as the undetermined speed at the historical wind turbine speed; determining the undetermined speeds that are greater than and less than the optimal speed of the wind turbine as the first historical speed and the second historical speed at the historical wind turbine speed, respectively; generating the kinetic energy storage curve based on the historical power and the first historical speed at each historical wind turbine speed; and generating the kinetic energy release curve based on the historical power and the second historical speed at each historical wind turbine speed.

[0079] In one embodiment, the method further includes: during the operation of each wind turbine at the corresponding target blade tip speed, determining whether the adjusted operating frequency is less than a first preset frequency; if the adjusted operating frequency is less than the first preset frequency, taking the adjusted operating frequency as the current frequency, and returning to the step of determining the frequency difference between the first preset frequency and the current frequency, so as to readjust the operating frequency of the power grid.

[0080] In one embodiment, the method further includes: when the adjusted operating frequency is greater than or equal to a first preset frequency and less than a second preset frequency, controlling each fan to run from the target blade tip speed to the fan's optimal speed or the current blade tip speed at the current wind speed.

[0081] In one embodiment, the method further includes: determining the operating state of the power grid as a frequency down-disturbance state when the current frequency is less than a first preset frequency; and determining the operating state of the power grid as a normal operating state when the current frequency is greater than the first preset frequency and less than a second preset frequency.

[0082] This application also provides a computer program product that, when executed on a data processing device, is adapted to execute a program having method steps for controlling the operating frequency of a power grid.

[0083] Those skilled in the art will understand that embodiments of this application can be provided as methods, systems, or computer program products. Therefore, this application can take the form of a completely hardware embodiment, a completely software embodiment, or an embodiment combining software and hardware aspects. Furthermore, this application can take the form of a computer program product embodied on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0084] This application is described with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of this application. It will be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, special-purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, generate instructions for implementing the flowchart... Figure 1 One or more processes and / or boxes Figure 1 A device that provides the functions specified in one or more boxes.

[0085] These computer program instructions may also be stored in a computer-readable storage medium that can direct a computer or other programmable data processing device to function in a particular manner, such that the instructions stored in the computer-readable storage medium produce an article of manufacture including instruction means, which are implemented in a process Figure 1 One or more processes and / or boxes Figure 1 The function specified in one or more boxes.

[0086] These computer program instructions may also be loaded onto a computer or other programmable data processing equipment to cause a series of operational steps to be performed on the computer or other programmable equipment to produce a computer-implemented process, thereby providing instructions that execute on the computer or other programmable equipment for implementing the process. Figure 1 One or more processes and / or boxes Figure 1 The steps of the function specified in one or more boxes.

[0087] In a typical configuration, a computing device includes one or more processors (CPU), input / output interfaces, network interfaces, and memory.

[0088] Memory may include non-persistent memory in computer-readable media, such as random access memory (RAM) and / or non-volatile memory, such as read-only memory (ROM) or flash RAM. Memory is an example of computer-readable media.

[0089] Computer-readable media includes both permanent and non-permanent, removable and non-removable media that can store information using any method or technology. Information can be computer-readable instructions, data structures, modules of programs, or other data. Examples of computer storage media include, but are not limited to, phase-change memory (PRAM), static random access memory (SRAM), dynamic random access memory (DRAM), other types of random access memory (RAM), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), flash memory or other memory technologies, CD-ROM, digital versatile optical disc (DVD) or other optical storage, magnetic tape, magnetic disk storage or other magnetic storage devices, or any other non-transferable medium that can be used to store information accessible by a computing device. As defined herein, computer-readable media does not include transient computer-readable media, such as modulated data signals and carrier waves.

[0090] It should also be noted that the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus. Unless otherwise specified, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes that element.

[0091] The above are merely embodiments of this application and are not intended to limit the scope of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of the claims of this application.

Claims

1. A method for controlling the operating frequency of a power grid, characterized in that, The method includes: For each wind turbine in the power grid, under the condition that the wind turbine is in a preset operating state, the current wind speed of the wind turbine and the current frequency of the power grid are obtained; The current power and current blade tip speed of the wind turbine are determined based on the first historical power and the first historical speed corresponding to the current wind speed in the kinetic energy storage curve of the wind turbine. When the current frequency is less than the first preset frequency, the frequency difference between the first preset frequency and the current frequency is determined, and the power increment of the wind turbine under the frequency difference is determined. The target tip rotation speed of the wind turbine is determined based on the power increment, the current power, and the current wind speed. Each wind turbine is controlled to operate from its current tip speed to its corresponding target tip speed, so as to convert the kinetic energy released by each wind turbine into electrical energy, thereby adjusting the operating frequency of the power grid; The step of determining the target tip rotation speed of the wind turbine based on the power increment, the current power, and the current wind speed includes: Obtain the second historical power and the second historical speed corresponding to the current wind speed from the kinetic energy release curve of the wind turbine; The target power of the wind turbine is determined based on the power increment, the current power, and the second historical power. Determine at least one candidate blade tip rotation speed corresponding to the target power, wherein each candidate blade tip rotation speed is greater than the second historical rotation speed and less than the first historical rotation speed; The highest selectable blade tip speed among all the selectable blade tip speeds is determined as the target blade tip speed; The method further includes: For each wind turbine in the power grid, obtain multiple historical tip speeds of the wind turbine at each historical wind speed; For each historical fan speed, the optimal tip speed ratio of the fan at the historical fan speed is determined based on the historical fan speed and the corresponding multiple historical tip speeds. For each historical fan wind speed, determine the optimal fan power and optimal fan speed corresponding to the optimal tip speed ratio at that historical fan wind speed; The ideal power curve of the wind turbine is generated based on the optimal power and optimal speed of the wind turbine at each historical wind speed. The kinetic energy storage curve and the kinetic energy release curve are determined based on the ideal power curve.

2. The method for controlling the operating frequency of a power grid according to claim 1, characterized in that, Determining the kinetic energy storage curve and the kinetic energy release curve based on the ideal power curve includes: For each historical wind turbine wind speed, the product of a preset coefficient and the optimal power of the wind turbine at that historical wind turbine wind speed is determined as the historical power at that historical wind turbine wind speed; The historical blade tip rotation speed corresponding to the historical power is determined as the undetermined rotation speed under the historical wind speed. The undetermined speeds that are greater than and less than the optimal speed of the fan are respectively determined as the first historical speed and the second historical speed under the historical fan wind speed; The kinetic energy storage curve is generated based on the historical power and the first historical rotational speed at each historical wind turbine wind speed. The kinetic energy release curve is generated based on the historical power and second historical rotational speed at each historical wind turbine wind speed.

3. The method for controlling the operating frequency of a power grid according to claim 1, characterized in that, The method further includes: During the operation of each fan at the corresponding target blade tip speed, it is determined whether the adjusted operating frequency is less than the first preset frequency; If the adjusted operating frequency is less than the first preset frequency, the adjusted operating frequency is taken as the current frequency, and the process returns to the step of determining the frequency difference between the first preset frequency and the current frequency, so as to readjust the operating frequency of the power grid.

4. The method for controlling the operating frequency of a power grid according to claim 3, characterized in that, The method further includes: When the adjusted operating frequency is greater than or equal to the first preset frequency and less than the second preset frequency, each fan is controlled to run from the target blade tip speed to the fan's optimal speed or the current blade tip speed at the current wind speed.

5. The method for controlling the operating frequency of a power grid according to claim 1, characterized in that, The method further includes: If the current frequency is less than the first preset frequency, the operating state of the power grid is determined to be a frequency under-disturbance state. If the current frequency is greater than the first preset frequency and less than the second preset frequency, the power grid is determined to be in normal operating condition.

6. A device for controlling the operating frequency of a power grid, characterized in that, The device includes: The memory is configured to store instructions; and A processor is configured to retrieve the instructions from the memory and, when executing the instructions, to implement the method for controlling the operating frequency of a power grid according to any one of claims 1 to 5.

7. A machine-readable storage medium, characterized in that, The machine-readable storage medium stores instructions for causing the machine to perform the method for controlling the operating frequency of the power grid according to any one of claims 1 to 5.

8. A processor, characterized in that, It is configured to perform the method for controlling the operating frequency of the power grid as described in any one of claims 1 to 5.

Images