Frequency coordination control method and system for wind farm group

Abstract

The present invention provides a frequency coordination control method and system for a wind farm group, comprising: obtaining the frequency modulation power shortage within the wind farm group, as well as the current active output and predicted power output of all wind farms in the wind farm group in each future time period; determining a priority sequence for all wind farms in the wind farm group to participate in frequency modulation based on the current active output and predicted power output of all wind farms in the wind farm group in each future time period; selecting wind farms participating in frequency modulation from the priority sequence based on the frequency modulation power shortage, and allocating frequency modulation power to each wind farm participating in frequency modulation. The present invention performs frequency modulation at the wind farm group level, sorting wind farms within the wind farm group according to performance indicators, allowing wind farms with high performance to participate in frequency modulation, and avoiding all wind farms participating in frequency modulation. This can improve the coordination and consistency of frequency modulation control and reduce mechanical wear and life reduction caused by frequency modulation in related wind farms.

Description

Technical Field

[0001] The present invention relates to the technical field of power system automation, and in particular to a frequency coordination control method and system for a wind farm group. Background Art

[0002] With the rapid and large-scale development of renewable energy sources like wind power, the power system has placed requirements on their participation in primary frequency regulation. Primary frequency regulation refers to an automatic control process in which the control systems of generators within the grid automatically increase or decrease their active power when the grid frequency deviates from the rated value, limiting frequency fluctuations and maintaining a stable grid frequency. Therefore, when the grid frequency rises, primary frequency regulation requires the generators to quickly reduce their load, and vice versa. This requires wind turbines and other renewable energy sources to participate in rapid frequency response, thereby improving the frequency safety of the larger grid.

[0003] Currently, there are various ways for wind power to participate in primary frequency regulation. For example, wind farms can be equipped with energy storage devices to support grid frequency; frequency regulation can be achieved by modifying the wind turbine control system; and frequency regulation can be achieved by adding frequency regulation functions to the wind farm's power control system. The inventors have discovered that frequency regulation can be achieved by modifying the wind farm's power control system. When the grid experiences a frequency deviation, i.e., exceeding the frequency regulation dead zone, all wind turbines in the wind farm are activated. Alternatively, frequency regulation can be achieved by modifying the wind turbines themselves. When the grid experiences a frequency deviation, i.e., exceeding the frequency regulation dead zone, all wind turbines are also activated. However, the power required for frequency regulation varies depending on the magnitude of the disturbance or fault; not all disturbances or faults require significant frequency regulation power. Frequency regulation requires mechanical components such as pitch control for wind turbines, and frequent wind turbine operation can cause varying degrees of wear and tear, reducing the wind turbine's service life. In addition, wind turbines participate in frequency regulation very quickly. Currently, wind farms can also participate in frequency regulation very quickly (for example, the regulation process is completed within 500ms). A frequency regulation process generally lasts 10-60 seconds. Therefore, based on the current new technology, the inventors propose that the frequency regulation control process can be realized in a larger range, and large-scale coordinated optimization can be achieved to avoid frequent operation of more wind farms or wind turbines. Summary of the Invention

[0004] In order to solve the problems existing in the prior art, the present invention provides a frequency coordination control method for a wind farm group, comprising:

[0005] Obtaining the frequency regulation power shortage within the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0006] Determining a priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0007] Wind farms participating in frequency regulation are selected from the priority sequence based on the frequency regulation power shortage, and frequency regulation power is allocated to each wind farm participating in frequency regulation.

[0008] Preferably, determining the priority sequence of all wind farms in the wind farm group for participating in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the predicted power output in each future time period includes:

[0009] Based on the current active power output of each wind farm and the predicted power output in each future period, the wind power output sequence of each wind farm is constructed;

[0010] Fit the wind power output sequence of each wind farm based on the least squares method to obtain the slope of the fitting curve of each wind farm at the current moment;

[0011] Based on the current slope of the fitting curve of each wind farm and the priority set for each wind farm, a priority sequence of wind farms for increasing power generation when participating in upward frequency regulation and a priority sequence of wind farms for reducing power generation when participating in downward frequency regulation within the wind farm group are determined.

[0012] Preferably, determining the priority sequence of wind farms for increasing power generation when participating in upward frequency regulation and the priority sequence of wind farms for decreasing power generation when participating in downward frequency regulation within the wind farm group based on the slope of the fitting curve of each wind farm at the current moment and the priority set for each wind farm includes:

[0013] Arrange all wind farms whose fitting curve slope is greater than 0 at the current moment in descending order according to their response time and regulation rate, to obtain a priority sequence of additional wind farms participating in upward frequency regulation within the wind farm group;

[0014] All wind farms whose fitting curve slopes at the current moment are less than 0 are arranged in descending order according to their response time and regulation rate, so as to obtain a priority sequence of wind farms that participate in frequency reduction within the wind farm group.

[0015] Preferably, the step of arranging all wind farms whose fitting curve slopes at the current moment are greater than 0 in descending order according to their response time and regulation rate to obtain a priority sequence of additional wind farms participating in upward frequency regulation within the wind farm group further includes:

[0016] When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment;

[0017] The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the load rates being sorted in ascending order.

[0018] Preferably, the step of arranging all wind farms whose fitting curve slopes at the current moment are less than 0 in descending order according to their response time and regulation rate to obtain a priority sequence of wind farms for reducing power generation when participating in downward frequency regulation within the wind farm group further includes:

[0019] When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment;

[0020] The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the descending sorting of the load rates.

[0021] Preferably, after determining the priority sequence of all wind farms in the wind farm group for participating in frequency modulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period, the method further includes:

[0022] Based on the safety and stability constraint boundaries of each wind farm, the total increaseable power of the wind farm group in the increase wind farm priority sequence and the total decreaseable power of the wind farm group in the decrease wind farm priority sequence are obtained respectively.

[0023] Preferably, the selecting the wind farms participating in frequency regulation from the priority sequence based on the frequency regulation power shortage and allocating frequency regulation power to each wind farm participating in frequency regulation includes:

[0024] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is greater than or equal to the total additional power that can be generated, any wind farm is selected from the priority sequence of additional wind farms to participate in frequency modulation, and the additional frequency modulation power of the wind farm is equal to the maximum additional power of the wind farm;

[0025] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is less than the total additional power that can be generated, multiple wind farms are selected from the priority sequence of additional wind farms in descending order to participate in frequency modulation, and a frequency modulation power increase quota is allocated to each wind farm based on the maximum additional power of each wind farm;

[0026] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is greater than or equal to the total power that can be reduced, any wind farm is selected from the priority sequence of wind farms for reduction in power to participate in frequency regulation, and the frequency regulation power reduction quota of the wind farm is the maximum power reduction quota of the wind farm;

[0027] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is less than the total power that can be reduced, multiple wind farms are selected from the priority sequence of wind farms for frequency regulation from the first to the last, and a frequency regulation power reduction quota is allocated to each wind farm based on the maximum power reduction of each wind farm.

[0028] Preferably, the step of selecting a plurality of wind farms from the priority sequence of additional wind farms to participate in frequency modulation includes:

[0029] The last wind farm among the multiple wind farms is used as a redundancy margin, and the sum of the maximum additional power of the remaining wind farms is made ≥ the frequency regulation power shortage.

[0030] Preferably, the selecting of multiple wind farms from the priority sequence of wind farms with reduced power generation from earliest to latest to participate in frequency modulation includes:

[0031] The last wind farm among the multiple wind farms is used as a redundancy margin, and the sum of the maximum reduced power of the remaining wind farms is made ≥ the frequency regulation power shortage.

[0032] Preferably, the frequency regulation power is allocated to each wind farm participating in the frequency regulation according to the following formula:

[0033]

[0034] Where: ΔP i : The frequency regulation power allocated to each wind farm i participating in frequency regulation; ΔP i max+ : Maximum additional power; ΔP i max- : Maximum power reduction; ΔP: FM power shortage; Total power that can be increased; The total power that can be reduced; m: the number of wind farms in the priority sequence of wind farms for increasing power; q: the number of wind farms selected from the priority sequence of wind farms for increasing power to participate in frequency regulation from the first to the last; s: the number of wind farms in the priority sequence of wind farms for reducing power; h: the number of wind farms selected from the priority sequence of wind farms for reducing power to participate in frequency regulation from the first to the last.

[0035] Based on the same inventive concept, the present invention also provides a frequency coordination control system for a wind farm group, comprising:

[0036] An acquisition module is used to obtain the frequency regulation power shortage in the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0037] a processing module, configured to determine a priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0038] The control module is configured to select a wind farm participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocate frequency regulation power to each wind farm participating in frequency regulation.

[0039] Preferably, the control module is specifically used to:

[0040] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is greater than or equal to the total additional power that can be generated, any wind farm is selected from the priority sequence of additional wind farms to participate in frequency modulation, and the additional frequency modulation power of the wind farm is equal to the maximum additional power of the wind farm;

[0041] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is less than the total additional power that can be generated, multiple wind farms are selected from the priority sequence of additional wind farms in descending order to participate in frequency modulation, and a frequency modulation power increase quota is allocated to each wind farm based on the maximum additional power of each wind farm;

[0042] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is greater than or equal to the total power that can be reduced, any wind farm is selected from the priority sequence of wind farms for reduction in power to participate in frequency regulation, and the frequency regulation power reduction quota of the wind farm is the maximum power reduction quota of the wind farm;

[0043] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is less than the total power that can be reduced, multiple wind farms are selected from the priority sequence of wind farms for frequency regulation from the first to the last, and a frequency regulation power reduction quota is allocated to each wind farm based on the maximum power reduction of each wind farm.

[0044] Compared with the prior art, the present invention has the following beneficial effects:

[0045] The technical solution provided by the present invention obtains the frequency regulation power shortage within a wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; determines the priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; selects wind farms participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocates frequency regulation power to each wind farm participating in frequency regulation. When frequency regulation is required, this technical solution can determine the wind farms participating in frequency regulation from the wind farm group, avoiding the participation of all wind farms in frequency regulation, reducing mechanical wear of wind turbines in the wind farm, extending the service life of wind turbines, and improving the coordination and consistency of frequency regulation control. BRIEF DESCRIPTION OF THE DRAWINGS

[0046] Figure 1 A flow chart of a frequency coordination control method for a wind farm group provided by the present invention;

[0047] Figure 2 Schematic diagram of hierarchical frequency modulation structure of wind turbine generator set, wind farm, wind farm group and cluster in spatial scale in the present invention;

[0048] Figure 3 Schematic diagram of the framework of the multi-layer hierarchical integrated frequency regulation scheme of wind turbine group, wind farm, wind farm group and cluster in the present invention;

[0049] Figure 4 This is a detailed flow chart of the optimized coordinated allocation strategy for frequency modulation power in an embodiment of the present invention. DETAILED DESCRIPTION

[0050] In order to better understand the present invention, the present invention is further described below with reference to the accompanying drawings and examples.

[0051] Example 1:

[0052] like Figure 1 As shown, the present invention provides a frequency coordination control method for a wind farm group, comprising:

[0053] S1 obtains the frequency regulation power shortage in the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0054] S2 determines the priority sequence of all wind farms in the wind farm group for participating in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0055] S3 selects wind farms participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocates frequency regulation power to each wind farm participating in frequency regulation.

[0056] The technical solution provided by the embodiment of the present invention realizes primary frequency regulation at the level of the wind farm group. According to the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period, the order of participating in the frequency regulation of all wind farms in the wind farm group is sorted to avoid all wind farms participating in the frequency regulation. On the one hand, it can improve the coordination and consistency of the frequency regulation control, and on the other hand, it can reduce the mechanical wear and life reduction of the relevant wind farms caused by the frequency regulation.

[0057] This embodiment specifically explains the technical solution through the following examples:

[0058] Step 1: If Figure 2 As shown in the figure, wind farms with close geographical locations, similar wind characteristics, and access to the same grid connection point are aggregated to form wind farm groups, which are further aggregated into clusters. From a spatial scale, a hierarchical structure of wind turbines-wind farms-wind farm groups-wind power clusters is established, as shown in the figure. Figure 3 On this basis, a hierarchical and integrated frequency coordination control scheme framework for wind turbines / wind farms / wind farm groups / wind power clusters is given.

[0059] By adopting the natural physical distribution structure of wind turbines-wind farms-wind farm groups-wind power clusters, an opportunity is provided to achieve frequency coordination control of clusters.

[0060] This embodiment is achieved by Figure 4 The specific steps of a frequency coordination control method for a wind farm group are described below:

[0061] Step 2: Obtain basic data for all wind farms in the wind farm group, including:

[0062] Step 2-1: Obtain the frequency modulation power difference ΔP issued by the cluster dispatch center: if ΔP>0, increase the power; if ΔP<0, reduce the power;

[0063] Step 2-2: Assume that wind farm group A = {A1, A2, ..., A n}, get wind farm A i Installed capacity (i.e. active power rating) P i N , i=1,2,…,n;

[0064] Step 2-3: According to the wind power prediction system, obtain wind farm A i The active power output P at the current moment k i (k) and the power prediction output P for the next 3 minutes i pre (k+1),P i pre (k+2),P i pre (k+3), i=1,2,…,n.

[0065] Step 3: Obtain the priority sequence of wind farms through optimized grouping, including:

[0066] Step 3-1: Construct wind farm A i Wind power output sequence

[0067] [P i (k),P i pre (k+1),P i pre (k+2),P i pre (k+3)], i=1,2,…,n.

[0068] Step 3-2: Fit the wind power output sequence according to the least squares method to obtain the wind farm Ai The slope of the fitting curve at the current moment k like Description of the wind farm A i There is a short-term trend of increasing power; if Description of the wind farm A i There is a short-term trend of power reduction, i = 1, 2,…, n.

[0069] Step 3-3: Calculate wind farm A i The load rate of k at the current moment:

[0070]

[0071] Where: δ i (k) is wind farm A i The load rate at the current moment k; P i (k) is wind farm A i The active power output of k at the current moment; P i N Wind farm A i installed capacity.

[0072] Step 3-4: Based on the response time t 0.9 and adjustment rate t v The two frequency regulation indicators give the priority classification of wind farms, as shown in Table 1:

[0073] Table 1 Priority classification of wind farms

[0074]

[0075] Step 3-5: Select the slope of the fitting curve The wind farms are sorted from high to low according to their priorities. If the priorities are the same, they are further sorted according to the load rate δ i (k) Sort by order from low to high to form a priority sequence for additional issuance, denoted as A + ={A1,A2,…,A m}, obviously m≤n. At the same time, select the slope of the fitting curve The wind farms are sorted from high to low according to their priorities. If the priorities are the same, they are further sorted according to the load rate δ i (k) is sorted from high to low to form a priority sequence for reduction, denoted as Obviously s≤n.

[0076] The embodiment of the present invention ranks wind farms in a wind farm group according to performance indicators, allowing wind farms with good performance to participate in frequency modulation first, avoiding all wind farms from participating in frequency modulation, and reducing mechanical wear and life reduction of related wind farms caused by frequency modulation.

[0077] Step 4: Calculate the maximum increase / decrease power: ΔP i max+ , ΔP i max- 、 include:

[0078] For the additional issuance of priority sequence A + ={A1,A2,…,A m}, A i The maximum additional power is shown as follows:

[0079] ΔP i max+ =min{P i pre (k+1)-P i (k),0.1P i N}(i=1,2,…,m)

[0080] The total additional power that can be generated by wind farm group A is calculated as follows:

[0081]

[0082] Prioritize hair reduction Maximum power reduction:

[0083] ΔP i max- =min{P i (k)-P i pre (k+1),0.1P i N}(i=1,2,…,s)

[0084] The total power that can be reduced by wind farm group A is shown in the following formula:

[0085]

[0086] Considering the safe operation, this embodiment sets up wind farm A i The maximum increase / decrease in active power output should not exceed 0.1P i N .

[0087] Step 5: Allocate frequency regulation power to the wind farms participating in frequency regulation. The specific steps are as follows:

[0088] Step 5-1: If ΔP>0, it is necessary to increase the power, and the priority sequence A is selected. + ={A1,A2,…,A m}, the specific allocation strategy is as follows:

[0089] Step 5-1-1: If Wind farm A i The additional amount of frequency modulation power ΔP i Assigned as ΔP i =ΔP i max+ , i=1,2,…,m;

[0090] Step 5-1-2: If Then from A + ={A1,A2,…,A m}, select q+1 wind farms (q+1≤m) from the front to the back, and make the first q wind farms satisfy

[0091]

[0092] The q+1th wind farm serves as a redundant margin to cope with the possible additional power shortage caused by the prediction error.

[0093] At this time, wind farm A i The additional amount of frequency modulation power ΔP i Assigned as:

[0094]

[0095] Step 5-2: If ΔP < 0, the power needs to be reduced. At this time, the power reduction priority sequence is selected. The specific allocation strategies are as follows:

[0096] Step 5-2-1: If Wind farm Frequency modulation power reduction ΔP i Assigned as ΔP i =ΔP i max- , i=1,2,…,s;

[0097] Step 5-2-2: If Then from Select q+1 wind farms (q+1≤s) from the front to the back, and make the first q wind farms satisfy

[0098]

[0099] The q+1th wind farm serves as a redundant margin to cope with the possible power reduction caused by the prediction error.

[0100] At this time, the wind farm Frequency modulation power reduction ΔP i Assigned as

[0101]

[0102] The technical solution provided by the present invention realizes the centralized optimization and coordination of different types of wind power frequency regulation resources, which is conducive to achieving the safety and economic coordination of the overall frequency regulation control of the system, and realizes the supporting role of large-scale wind power participation in grid frequency regulation on the frequency stability of the power system.

[0103] Example 2:

[0104] Based on the same inventive concept, the present invention also provides a frequency coordination control system for a wind farm group, comprising:

[0105] An acquisition module is used to obtain the frequency regulation power shortage in the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0106] a processing module, configured to determine a priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period;

[0107] A control module is configured to select a wind farm participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocate frequency regulation power to each wind farm participating in frequency regulation.

[0108] In an embodiment, the processing module includes:

[0109] The sequence construction submodule is used to construct the wind power output sequence of each wind farm based on the active power output of each wind farm at the current moment and the power forecast output in each future time period;

[0110] The fitting submodule is used to fit the wind power output sequence of each wind farm based on the least squares method to obtain the slope of the fitting curve of each wind farm at the current moment;

[0111] The grouping and sorting submodule is used to determine the priority sequence of wind farms that increase power generation when participating in upward frequency regulation and the priority sequence of wind farms that reduce power generation when participating in downward frequency regulation within the wind farm group based on the slope of the fitting curve of each wind farm at the current moment and the priority set for each wind farm.

[0112] In an embodiment, the group sorting submodule includes:

[0113] The additional issuance sequence unit is used to arrange all wind farms whose fitting curve slope is greater than 0 at the current moment in descending order according to the response time and regulation rate of each wind farm, so as to obtain a priority sequence of additional issuance wind farms in the wind farm group when participating in upward frequency regulation;

[0114] The power reduction sequence unit is used to arrange all wind farms whose fitting curve slope is less than 0 at the current moment in descending order according to the response time and regulation rate of each wind farm, and obtain the priority sequence of wind farms participating in the power reduction when downward frequency regulation is performed within the wind farm group.

[0115] In an embodiment, the additional issuance sequence unit is further used to:

[0116] When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment;

[0117] The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the load rates being sorted in ascending order.

[0118] In an embodiment, the emission reduction sequence unit is further configured to:

[0119] When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment;

[0120] The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the descending sorting of the load rates.

[0121] In an embodiment, after executing the processing module, a calculation module is called, and the calculation module is specifically used to:

[0122] Based on the safety and stability constraint boundaries of each wind farm, the total increaseable power of the wind farm group in the increase wind farm priority sequence and the total decreaseable power of the wind farm group in the decrease wind farm priority sequence are obtained respectively.

[0123] In an embodiment, the control module is specifically used to:

[0124] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is greater than or equal to the total additional power that can be generated, any wind farm is selected from the priority sequence of additional wind farms to participate in frequency modulation, and the additional frequency modulation power of the wind farm is equal to the maximum additional power of the wind farm;

[0125] When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is less than the total additional power that can be generated, multiple wind farms are selected from the priority sequence of additional wind farms in descending order to participate in frequency modulation, and a frequency modulation power increase quota is allocated to each wind farm based on the maximum additional power of each wind farm;

[0126] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is greater than or equal to the total power that can be reduced, any wind farm is selected from the priority sequence of wind farms for reduction in power to participate in frequency regulation, and the frequency regulation power reduction quota of the wind farm is the maximum power reduction quota of the wind farm;

[0127] When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is less than the total power that can be reduced, multiple wind farms are selected from the priority sequence of wind farms for frequency regulation from the first to the last, and a frequency regulation power reduction quota is allocated to each wind farm based on the maximum power reduction of each wind farm.

[0128] In the embodiment, the frequency modulation power is allocated to each wind farm participating in the frequency modulation according to the following formula:

[0129]

[0130] Where: ΔP i : The frequency regulation power allocated to each wind farm i participating in frequency regulation; ΔP i max+ : Maximum additional power; ΔP i max- : Maximum power reduction; ΔP: FM power shortage; Total power that can be increased; The total power that can be reduced; m: the number of wind farms in the priority sequence of wind farms for increasing power; q: the number of wind farms selected from the priority sequence of wind farms for increasing power to participate in frequency regulation from the first to the last; s: the number of wind farms in the priority sequence of wind farms for reducing power; h: the number of wind farms selected from the priority sequence of wind farms for reducing power to participate in frequency regulation from the first to the last.

[0131] Obviously, the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work are within the scope of protection of the present invention.

[0132] Those skilled in the art will appreciate that the embodiments of the present application can be provided as methods, systems, or computer program products. Therefore, the present application can adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application can adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage, CD-ROM, optical storage, etc.) that contain computer-usable program code.

[0133] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0134] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0135] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0136] The above are merely embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention are included in the scope of the claims of the present invention to be approved.

Claims

1. A frequency coordination control method for a wind farm group, characterized in that: include: Obtaining the frequency regulation power shortage within the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; Determining a priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; selecting a wind farm participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocating frequency regulation power to each wind farm participating in frequency regulation; The determining of the priority sequence of all wind farms in the wind farm group for participating in frequency modulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period includes: Based on the current active power output of each wind farm and the predicted power output in each future period, the wind power output sequence of each wind farm is constructed; Fit the wind power output sequence of each wind farm based on the least squares method to obtain the slope of the fitting curve of each wind farm at the current moment; Determining, based on the slope of the fitting curve of each wind farm at the current moment and the priority set for each wind farm, a priority sequence of wind farms that increase power generation when participating in upward frequency regulation and a priority sequence of wind farms that decrease power generation when participating in downward frequency regulation within the wind farm group; After determining the priority sequence of all wind farms in the wind farm group for participating in frequency modulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period, the method further includes: Based on the safety and stability constraint boundaries of each wind farm, the total power that can be increased by the wind farm group in the priority sequence of increased wind farms and the total power that can be reduced by the wind farm group in the priority sequence of reduced wind farms are obtained respectively; The selecting the wind farms participating in the frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocating frequency regulation power to each wind farm participating in the frequency regulation, includes: When the FM power deficit>0 and the FM power deficit When the total power that can be increased is less than the specified value, any wind farm is selected from the priority sequence of wind farms for increased power to participate in frequency regulation, and the amount of increased frequency regulation power of the wind farm is equal to the maximum increased power of the wind farm; When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is less than the total additional power that can be generated, multiple wind farms are selected from the priority sequence of additional wind farms in descending order to participate in frequency modulation, and a frequency modulation power increase quota is allocated to each wind farm based on the maximum additional power of each wind farm; When the FM power deficit is less than 0 and the absolute value of the FM power deficit is When the total power that can be reduced is less than the power output, any wind farm is selected from the priority sequence of wind farms for reduction to participate in frequency regulation, and the frequency regulation power reduction amount of the wind farm is the maximum power reduction amount of the wind farm; When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is less than the total power that can be reduced, multiple wind farms are selected from the priority sequence of wind farms for frequency regulation from the first to the last, and a frequency regulation power reduction quota is allocated to each wind farm based on the maximum power reduction of each wind farm.

2. The method according to claim 1, wherein The determining, based on the slope of the fitting curve of each wind farm at the current moment and the priority set for each wind farm, a priority sequence of wind farms for increasing power generation when participating in upward frequency regulation and a priority sequence of wind farms for decreasing power generation when participating in downward frequency regulation within the wind farm group includes: Arrange all wind farms whose fitting curve slope is greater than 0 at the current moment in descending order according to their response time and regulation rate, to obtain a priority sequence of additional wind farms participating in upward frequency regulation within the wind farm group; All wind farms whose fitting curve slopes at the current moment are less than 0 are arranged in descending order according to their response time and regulation rate, so as to obtain a priority sequence of wind farms that participate in frequency reduction within the wind farm group.

3. The method according to claim 2, wherein The step of arranging all wind farms whose fitting curve slopes at the current moment are greater than 0 in descending order according to the response time and regulation rate of each wind farm to obtain a priority sequence of additional wind farms participating in upward frequency regulation within the wind farm group further includes: When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment; The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the load rates being sorted in ascending order.

4. The method according to claim 2, wherein The step of arranging all wind farms whose fitting curve slopes at the current moment are less than 0 in descending order according to the response time and regulation rate of each wind farm to obtain a priority sequence of wind farms for reducing power generation when participating in downward frequency regulation within the wind farm group further includes: When there are multiple wind farms with the same response time and regulation rate, calculating the load rate of each wind farm at the current moment based on the installed capacity and active power output of the multiple wind farms at the current moment; The priorities of the plurality of wind farms having the same response time and adjustment rate are determined based on the descending sorting of the load rates.

5. The method according to claim 1, wherein The step of selecting a plurality of wind farms from the priority sequence of additional wind farms in descending order to participate in frequency modulation includes: The last wind farm among multiple wind farms is used as the redundancy margin, and the sum of the maximum additional power of the remaining wind farms is The FM power shortage.

6. The method according to claim 1, wherein The step of selecting a plurality of wind farms from the priority sequence of wind farms with reduced power generation from the earliest to the latest to participate in frequency regulation includes: The last wind farm among multiple wind farms is used as the redundancy margin, and the sum of the maximum power reduction of the remaining wind farms is The FM power shortage.

7. The method according to claim 1, wherein The frequency regulation power is allocated to each wind farm participating in frequency regulation according to the following formula: Where: :For each wind farm participating in frequency regulation Allocated FM power; : Maximum additional power; : Maximum reduced power; : FM power shortage; : total power that can be increased; : total power that can be reduced; : the number of wind farms in the priority sequence of additional wind farms; : Select the number of wind farms participating in frequency regulation from the priority sequence of additional wind farms from the earliest to the latest; : the number of wind farms in the priority sequence of wind farms with reduced generation; : Select the number of wind farms participating in frequency regulation from the priority sequence of wind farms with reduced power generation from the earliest to the latest.

8. A frequency coordination control system for a wind farm group, characterized in that: include: An acquisition module is used to obtain the frequency regulation power shortage in the wind farm group, as well as the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; a processing module, configured to determine a priority sequence for all wind farms in the wind farm group to participate in frequency regulation based on the active power output of all wind farms in the wind farm group at the current moment and the power forecast output in each future time period; a control module, configured to select a wind farm participating in frequency regulation from the priority sequence based on the frequency regulation power shortage, and allocate frequency regulation power to each wind farm participating in frequency regulation; The processing module includes: Based on the current active power output of each wind farm and the predicted power output in each future period, the wind power output sequence of each wind farm is constructed; Fit the wind power output sequence of each wind farm based on the least squares method to obtain the slope of the fitting curve of each wind farm at the current moment; Determining, based on the slope of the fitting curve of each wind farm at the current moment and the priority set for each wind farm, a priority sequence of wind farms that increase power generation when participating in upward frequency regulation and a priority sequence of wind farms that decrease power generation when participating in downward frequency regulation within the wind farm group; Computing module, specifically including: Based on the safety and stability constraint boundaries of each wind farm, the total power that can be increased by the wind farm group in the priority sequence of increased wind farms and the total power that can be reduced by the wind farm group in the priority sequence of reduced wind farms are obtained respectively; The control module is specifically used for: When the FM power deficit>0 and the FM power deficit When the total power that can be increased is less than the specified value, any wind farm is selected from the priority sequence of wind farms for increased power to participate in frequency regulation, and the amount of increased frequency regulation power of the wind farm is equal to the maximum increased power of the wind farm; When the frequency modulation power shortage is greater than 0 and the frequency modulation power shortage is less than the total additional power that can be generated, multiple wind farms are selected from the priority sequence of additional wind farms in descending order to participate in frequency modulation, and a frequency modulation power increase quota is allocated to each wind farm based on the maximum additional power of each wind farm; When the FM power deficit is less than 0 and the absolute value of the FM power deficit is When the total power that can be reduced is less than the power output, any wind farm is selected from the priority sequence of wind farms for reduction to participate in frequency regulation, and the frequency regulation power reduction amount of the wind farm is the maximum power reduction amount of the wind farm; When the frequency regulation power shortage is less than 0 and the absolute value of the frequency regulation power shortage is less than the total power that can be reduced, multiple wind farms are selected from the priority sequence of wind farms for frequency regulation from the first to the last, and a frequency regulation power reduction quota is allocated to each wind farm based on the maximum power reduction of each wind farm.

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