A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency regulation

Abstract

The present invention proposes a high-frequency dynamic defense strategy for power grids that considers wind power participating in frequency modulation, and the steps include building a wind turbine participating in power grid frequency modulation model in power grid simulation software and inputting relevant parameters to perform simulation calculations for high-frequency events in the power grid; constructing an objective function for evaluating the degree of frequency recovery before and after the unit is removed; optimizing the capacity of the removed units under wind power participating in power grid frequency modulation based on the Gray Wolf optimization algorithm, and performing unit removal calculations based on the current proportion of wind turbines participating in power grid frequency modulation, so that the objective function reaches a smaller value; adjusting the wind-fire ratio in the power grid model to allow more wind turbines to participate in frequency modulation, and performing calculations again to obtain high-frequency dynamic defense strategies for power grids under different wind-fire ratios. The present invention provides a dynamic defense strategy for high-frequency events in power grids under wind power participating in frequency modulation, fully responds to events such as UHV DC single and double pole locking, prevents frequency collapse and long-term suspension of system frequency at a certain high value, and makes the power grid frequency stable and reliable.

Description

Technical Field

[0001] The present invention relates to a high-frequency dynamic defense strategy for a power grid considering the participation of wind power in frequency modulation, and in particular to a low-frequency defense strategy for a power grid considering the participation of wind power in frequency modulation based on a grey wolf optimization algorithm. Background Art

[0002] Frequency is an indispensable term in the field of power system, and frequency stability is a necessary condition for ensuring the safe operation of power system. Frequency changes in power system will have adverse effects on users, power plants and power system. The direct condition for maintaining frequency stability is to keep the frequency around the rated value of 50Hz and within the allowable deviation range. In order to solve the challenges of energy resources and environment, developed countries such as the United States began to study the utilization of wind energy in the 1970s. Since 1990, wind power technology has become increasingly mature, and the capacity of wind turbines has increased from the initial 25kW to the current 6MW, and continues to develop in the direction of large-scale. Wind farms have begun to be built on a large scale. The world's wind power generation has achieved unprecedented rapid development, and the demand for system inertia has gradually increased. In recent years, the current situation of large-scale grid-connected use of power electronic devices has made this demand more urgent. How to coordinate the increasing proportion of new energy and the decreasing system inertia has become the focus of research.

[0003] As the proportion of wind power in the power system continues to rise, it is crucial to take measures to release the inertia carried by wind turbines. Therefore, wind turbines assist thermal power units in participating in grid frequency regulation, which has become the general background for the formulation of the current dynamic defense strategy for the power grid. The safety and control cutting strategy under high-frequency events in the power grid can be derived through the wind turbine output formula, or it can be simulated through numerical simulation analysis. Modeling is done in the power system simulation software, parameters are edited, operating modes and fault conditions are set, and the scenario of wind turbines participating in the primary frequency regulation of the power grid is simulated. The optimization algorithm is selected to optimize the cutting amount to complete the high-frequency cutting calculation of the power grid in this scenario.

[0004] Research on dynamic defense strategies for power grids mostly analyzes the low-frequency load reduction link under low-frequency events, with less analysis of high-frequency events. In addition, most of the operation modes are for thermal power units to participate in grid frequency regulation alone. Considering the frequency response link and the wind turbine units with virtual inertia control switching participating in grid frequency regulation, dynamic defense strategies for power grids are areas that need further in-depth research in this field. Summary of the invention

[0005] The purpose of the present invention is to provide a high-frequency dynamic defense strategy for power grids that considers wind power participating in frequency modulation. The present invention takes into account the frequency modulation capability of wind turbines when the power grid model and operation mode are accurate. With the participation of wind turbines in power grid frequency modulation as the background, a model of wind turbines participating in power grid frequency modulation is built in the power grid simulation software and relevant parameters are input to perform simulation calculations of high-frequency events in the power grid; an objective function is constructed to evaluate the degree of frequency recovery before and after the unit is removed; the capacity of the removed unit under the participation of wind power in power grid frequency modulation is optimized based on the gray wolf optimization algorithm, and the unit removal calculation is performed for the current proportion of wind turbines participating in power grid frequency modulation, so that the objective function reaches a smaller value; the wind-fire ratio in the power grid model is adjusted so that more wind turbines participate in frequency modulation, and calculations are performed again to obtain a high-frequency dynamic defense strategy for power grids under different wind-fire ratios. The method provided by the present invention can provide a dynamic defense strategy for high-frequency events in power grids under the participation of wind power in frequency modulation, fully respond to events such as single and double pole locking of ultra-high voltage direct current, prevent frequency collapse and long-term suspension of system frequency at a certain high value, and create a reliable defense line for the stability of power grid frequency.

[0006] To achieve the above purpose, the technical solution adopted by the present invention is:

[0007] A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency regulation includes the following steps:

[0008] Step 1) Build a wind turbine model participating in grid frequency regulation in the grid simulation software and input relevant parameters to perform grid high-frequency event simulation calculations;

[0009] Step 2) constructing an objective function for evaluating the degree of frequency recovery before and after the unit is removed according to step 1);

[0010] Step 3) Based on the Grey Wolf Optimization Algorithm, the capacity of the removed units under the grid frequency regulation of wind power is optimized, and the unit removal calculation is performed according to the current proportion of wind turbines participating in the grid frequency regulation, so that the objective function reaches a smaller value;

[0011] Step 4) Output the result, and obtain the optimized power cut amount for the high-frequency dynamic defense strategy of the power grid under the wind-fire ratio;

[0012] Step 5) Adjust the wind-fire ratio in the power grid model so that more wind turbines can participate in frequency modulation, and perform calculations again to obtain the high-frequency dynamic defense strategy for the power grid under different wind-fire ratios.

[0013] The step 1) comprises the following steps:

[0014] 1. Select wind turbine types with good frequency regulation capability;

[0015] 2. Determine the type and quantity of wind turbines involved in frequency regulation, and set the basic parameters of wind turbines in the simulation system parameter library;

[0016] 3. Setting parameters for the frequency response link and virtual inertia control link of the wind turbines selected to participate in frequency regulation, so that the wind turbines have frequency regulation capability and assist the thermal power units in participating in grid frequency regulation;

[0017] 4. Identify and optimize the frequency response link and virtual inertia control link parameters of the wind turbines selected to participate in frequency regulation, to ensure that the grid frequency curve under the wind turbines participating in grid frequency regulation is more in line with reality;

[0018] 5. Complete parameter settings and add wind turbines to the regional power grid model;

[0019] 6. Complete the output setting of each unit.

[0020] The step 2) constructing the objective function model includes the following steps:

[0021] 1. Define evaluation indicators to evaluate the difference between the grid frequency before the high-frequency event occurs and the grid recovery frequency after the unit is removed. The evaluation indicators include the difference between the initial grid frequency increase value, the frequency drop value difference and the frequency peak-valley difference;

[0022] 2. Establish a target evaluation function for evaluating the frequency recovery degree before and after the unit is removed;

[0023] 3. Conduct a high-frequency event test considering the participation of wind power in frequency regulation, and perform high-frequency machine cutting calculation based on the unit capacity removal plan when wind power does not participate in frequency regulation. Obtain the above-mentioned evaluation index values ​​and bring them into the objective function for calculation to obtain the objective function value under the machine cutting amount.

[0024] The advantages of the present invention are:

[0025] 1. The present invention takes into account the ability of wind turbines to participate in grid frequency regulation. The constructed wind turbine model takes into account the frequency response link and the virtual management and control link. It can provide a dynamic defense strategy for high-frequency events in the grid under the participation of wind power in frequency regulation, and fully respond to events such as UHV DC single and double pole locking, prevent frequency collapse and long-term suspension of system frequency at a high value, and create a reliable defense line for the stability of grid frequency.

[0026] 2. The present invention takes into account the high-frequency defense strategy under the participation of wind power in frequency regulation, provides a key point of force for the field of power grid frequency defense, and further studies the low-frequency defense strategy under the participation of thermal power in frequency regulation studied by most scholars in the past. It is in line with the current situation faced by the power system and provides a more reliable machine cutting solution for power companies.

[0027] 3. The present invention adopts the Grey Wolf optimization algorithm. After verification by simulation calculation, the algorithm can accurately optimize the machine cutting scheme under the high-frequency dynamic defense strategy. It is suitable for the current situation where the proportion of wind power is constantly increasing, and is conducive to the safe and stable operation of the power grid. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 It is the overall flow chart of the method of the present invention;

[0029] Figure 2 This is a schematic diagram of the removal amount of high-frequency defense strategy units under different wind-fire ratios;

[0030] Figure 3-1 This is one of the grid frequency trajectory diagrams before the optimization of the generator shedding amount;

[0031] Figure 3-2 This is the second grid frequency trajectory diagram before the optimization of the power cut amount;

[0032] Figure 4-1 This is one of the grid frequency trajectory diagrams after the generator cutoff quantity is optimized;

[0033] Figure 4-2 This is the second grid frequency trajectory diagram after the generator cutting amount is optimized. DETAILED DESCRIPTION

[0034] Combined with the following instructions Figure 1 The present invention is described in detail with reference to the accompanying drawings and embodiments.

[0035] A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency regulation includes the following steps:

[0036] Step 1) Build a wind turbine model participating in grid frequency regulation in the grid simulation software and input relevant parameters to perform grid high-frequency event simulation calculations;

[0037] 1. Select wind turbine types with good frequency regulation capability;

[0038] 2. Determine the type and quantity of wind turbines involved in frequency regulation, and set the basic parameters of wind turbines in the simulation system parameter library;

[0039] 3. Setting parameters for the frequency response link and virtual inertia control link of the wind turbines selected to participate in frequency regulation, so that the wind turbines have frequency regulation capability and assist the thermal power units in participating in grid frequency regulation;

[0040] 4. Identify and optimize the frequency response link and virtual inertia control link parameters of the wind turbines selected to participate in frequency regulation, to ensure that the grid frequency curve under the wind turbines participating in grid frequency regulation is more in line with reality;

[0041] 5. Complete parameter settings and add wind turbines to the regional power grid model;

[0042] 6. Complete the output setting of each unit.

[0043] Step 2) Based on step 1), an objective function is constructed to evaluate the frequency recovery degree before and after the unit is removed; the objective function model can be summarized as follows:

[0044] 1. Define evaluation indicators to evaluate the difference between the grid frequency before the high-frequency event occurs and the grid recovery frequency after the unit is removed. The evaluation indicators include the difference between the initial grid frequency increase value, the frequency drop value difference and the frequency peak-valley difference;

[0045] 2. Establish a target evaluation function for evaluating the degree of frequency recovery before and after the unit is removed;

[0046] 3. Conduct a high-frequency event test considering the participation of wind power in frequency regulation, and perform high-frequency machine cutting calculation based on the unit capacity removal plan when wind power does not participate in frequency regulation. Obtain the above-mentioned evaluation index values ​​and bring them into the objective function for calculation to obtain the objective function value under the machine cutting amount.

[0047] Step 3) Based on the Grey Wolf Optimization Algorithm, the capacity of the removed units under the grid frequency regulation of wind power is optimized, and the unit removal calculation is performed according to the current proportion of wind turbines participating in the grid frequency regulation, so that the objective function reaches a smaller value;

[0048] 3-1 Given algorithm parameters based on the capacity of the unit to be optimized;

[0049] 32 Initialize the gray wolf population;

[0050] 3-3 Calculate the individual fitness of gray wolves. The top three wolves with the highest fitness are recorded as ,and ;

[0051] 3-4 Surround, hunt and attack prey to complete the wolf pack movement;

[0052] 3-5 Update the location information of individual gray wolves;

[0053] 3-6 Get multiple candidate solutions;

[0054] 3-7 Substitute the candidate solution obtained in step 6 into the high-frequency event simulation calculation of wind power participating in frequency regulation to obtain the grid frequency curve;

[0055] 3-8 Obtain the evaluation index value;

[0056] 3-9 Substitute the evaluation index value into the objective function for calculation, retain the solution with a smaller objective function value, and discard the solution with a larger objective function value;

[0057] 3-10 Continue to let the wolf pack surround and attack the prey, and update the wolf pack's position;

[0058] 3-11 Update candidate solutions;

[0059] 3-12 Termination criteria: If the maximum allowed number of iterations is reached or the objective function value has not improved after multiple consecutive iterations, the calculation is stopped, the results are output, and the optimal cutting amount is obtained;

[0060] 3-13 If the termination criteria are not met, repeat the above steps to continue the calculation;

[0061] Step 4) Output the result and obtain the optimized power curtailment amount for the high-frequency dynamic defense strategy of the power grid under the wind-fire ratio.

[0062] Step 5) Adjust the wind-fire ratio in the power grid model so that more wind turbines can participate in frequency modulation, and perform calculations again to obtain the high-frequency dynamic defense strategy for the power grid under different wind-fire ratios.

[0063] The process of building a wind turbine participating in the grid frequency regulation model in the grid simulation software and inputting relevant parameters to simulate the high-frequency events of the grid is as follows:

[0064] a. Build a regional power grid model in the power system simulation software and construct a scenario where wind turbines participate in power grid frequency regulation;

[0065] b. In the simulation software, build the wind turbine and related electrical component models according to the actual situation of the regional power grid, and set the parameters of each component;

[0066] c. Set the power system operation mode;

[0067] d. Set high-frequency event faults, such as UHV DC single and double pole blocking;

[0068] e. Conduct high-frequency event tests considering wind power participating in frequency regulation, and perform high-frequency unit removal calculations based on the unit removal plan when wind power does not participate in frequency regulation to obtain the grid frequency change trajectory.

[0069] The process of constructing the objective function for evaluating the degree of frequency recovery before and after the removal of the unit is as follows:

[0070] a. The indicator system is as follows:

[0071] The difference in the initial frequency rise value of the power grid is the absolute value of the difference in the frequency change trajectory of the power grid from the initial rise to the highest point after a high-frequency event occurs in the power grid;

[0072] Frequency drop value difference: It is the absolute value of the difference in the frequency change trajectory of the power grid when the frequency rises to a stable state after the power grid frequency curve reaches the peak;

[0073] Frequency peak-to-valley difference: It is the absolute value of the maximum difference of the grid frequency trajectory value on the frequency axis when the grid performs high-frequency switching calculation;

[0074] b. The objective function is defined as follows:

[0075] Formula 1

[0076] In formula 1: represents the objective function; Represents the numerical value corresponding to each evaluation index; Represents the weight coefficient corresponding to each evaluation index; Represents the number of evaluation indicators under the objective function;

[0077] The above-mentioned optimization of the capacity of the removed units under the grid frequency regulation of wind power based on the gray wolf optimization algorithm, and the calculation of the unit removal according to the current proportion of wind power units participating in the grid frequency regulation, so that the objective function reaches a smaller value means:

[0078] a. Randomly initialize the wolf group, obtain the initial value, and calculate the fitness value of each gray wolf;

[0079] b. Surround, hunt and attack prey to complete the movement of the wolf pack;

[0080] c. Update the position of the gray wolf, calculate the fitness value, and obtain the candidate solution;

[0081] d. Set the operation mode and fault conditions in the simulation model;

[0082] e. Substitute the candidate solution into the wind power frequency regulation simulation model for calculation, that is, modify the cutting amount in the model for simulation:

[0083] f. Obtain the grid frequency trajectory and record the evaluation indicators;

[0084] g. Substitute the objective function for calculation, obtain the objective function value, and compare it with the objective function value in the previous iteration result. The one with the smaller objective function value will enter the next iteration, and the one with the larger objective function value will be discarded;

[0085] h. Repeat the above steps. If the maximum allowed number of iterations is reached or the objective function value has not improved after multiple consecutive iterations, stop the calculation, output the results, and obtain the optimal load reduction;

[0086] The adjustment of the wind-fire ratio in the power grid model so that more wind turbines participate in frequency modulation and the calculation again to obtain the high-frequency dynamic defense strategy of the power grid under different wind-fire ratios is:

[0087] a. Query the units currently in operation in the component setting section of the power grid simulation system flow section;

[0088] b. Find the unit output summary table;

[0089] c. Calculate the capacity ratio of wind turbines and thermal power units put into operation under the current operating status;

[0090] d. Ensure that the total output of the system units remains unchanged, enter the parameter library, and modify the number of wind turbines and thermal power units to be started and stopped;

[0091] e. Carry out the flow quantity under this operation mode, output the report, and confirm that the wind-fire ratio has been modified;

[0092] f. Complete the high-frequency cutting calculation under the new wind-fire ratio according to the security control cutting steps under high-frequency events and the above-mentioned optimization algorithm steps;

[0093] g. Obtain the optimized generator cutting capacity under the new wind-fire ratio, which is used for the high-frequency dynamic defense strategy under the consideration of wind power participating in grid frequency regulation.

[0094] like Figure 2 As shown in the figure, the optimized cutting amount of wind turbines participating in grid frequency regulation under different wind-fire ratios is achieved. At the same time, it can also be found that after wind power participates in grid frequency regulation, the amount of units required for safety and control cutting process is less, and the frequency regulation effect will be more obvious.

[0095] like Figure 3-1 , Figure 3-2 , Figure 4-1 , Figure 4-2 As shown in Figure 2, it is the grid frequency trajectory diagram before and after optimizing the generator cutting amount under different wind-fire ratios.

[0096] When the wind-fire ratio of a regional power grid is 1:22 and 1:8 respectively, a bipolar blockage occurs in a DC line at 1s. In order to ensure that the transient frequency of the system does not exceed 51 Hz after the DC bipolar blockage, a safety control cutting operation is performed. Comparative simulation calculations are carried out with and without virtual synchronization links of wind turbines. The simulation time is 100s, and the simulation results are all controlled within 51Hz, about 50.7Hz. At the same time, with the increase in the proportion of wind power participating in grid frequency regulation, the capacity of safety control cutting has also been greatly reduced, which once again proves the importance of wind turbines assisting thermal power units in participating in grid frequency regulation.

Claims

1. A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation, characterized in that: The following steps are involved: Step 1) Build a wind turbine model participating in grid frequency regulation in the grid simulation software and input relevant parameters to perform grid high-frequency event simulation calculations; Step 2) constructing an objective function for evaluating the degree of frequency recovery before and after the unit is removed according to step 1); Step 3) Based on the Grey Wolf Optimization Algorithm, the capacity of the removed units under the grid frequency regulation of wind power is optimized, and the unit removal calculation is performed according to the current proportion of wind turbines participating in the grid frequency regulation, so that the objective function reaches a smaller value; Step 4) Output the results to obtain the optimized power cut amount for the high-frequency dynamic defense strategy of the power grid under the wind-fire ratio; Step 5) Adjust the wind-fire ratio in the power grid model so that more wind turbines can participate in frequency modulation, and perform calculations again to obtain the high-frequency dynamic defense strategy for the power grid under different wind-fire ratios; The step 2) constructing the objective function model includes the following steps:

1. Define evaluation indicators to evaluate the difference between the grid frequency before the high-frequency event occurs and the grid recovery frequency after the unit is removed. The evaluation indicators include the difference between the initial grid frequency increase value, the frequency drop value difference and the frequency peak-valley difference; 2. Establish a target evaluation function for evaluating the frequency recovery degree before and after the unit is removed; 3. Conduct a high-frequency event test considering wind power participating in frequency regulation, and perform high-frequency machine cutting calculation based on the machine cutting capacity plan when wind power does not participate in frequency regulation. Obtain the above evaluation index values ​​and bring them into the objective function for calculation to obtain the objective function value under the machine cutting amount. The process of constructing the objective function for evaluating the degree of frequency recovery before and after the removal of the unit is as follows; a. The indicator system is as follows: 1) Difference in the initial frequency rise value of the power grid: It is the absolute value of the difference in the frequency change trajectory of the power grid from the initial rise to the highest point after a high-frequency event occurs in the power grid; 2) Frequency drop value difference: It is the absolute value of the difference in the frequency change trajectory of the power grid when the frequency returns to a stable state after the power grid frequency curve reaches the peak; 3) Frequency peak-to-valley difference: It is the absolute value of the maximum difference of the grid frequency trajectory value on the frequency axis when the grid performs high-frequency generator switching calculation; b. The objective function is defined as follows: Formula 1 In formula 1: represents the objective function; represents the value corresponding to each evaluation index; Represents the weight coefficient corresponding to each evaluation index; Represents the number of evaluation indicators under the objective function.

2. According to claim 1, a high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation is characterized in that: The step 1) comprises the following steps:

1. Select wind turbine types with good frequency regulation capability; 2. Determine the type and quantity of wind turbines involved in frequency regulation, and set the basic parameters of wind turbines in the simulation system parameter library; 3. Setting parameters for the frequency response link and virtual inertia control link of the wind turbines selected to participate in frequency regulation, so that the wind turbines have frequency regulation capability and assist the thermal power units in participating in grid frequency regulation; 4. Identify and optimize the frequency response link and virtual inertia control link parameters of the wind turbines selected to participate in frequency regulation, to ensure that the grid frequency curve under the wind turbines participating in grid frequency regulation is more in line with reality; 5. Complete parameter settings and add wind turbines to the regional power grid model; 6. Complete the output setting of each unit.

3. According to claim 1, a high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation is characterized in that: The step 3) includes the following steps 3-1 Given algorithm parameters based on the capacity of the unit to be optimized; 3-2 Initialize the gray wolf population; 3-3 Calculate the individual fitness of gray wolves. The top three wolves with the highest fitness are recorded as ,and ; 3-4 Surround, hunt and attack prey to complete the wolf pack movement; 3-5 Update the location information of individual gray wolves; 3-6 Get multiple candidate solutions; 3-7 Substitute the candidate solution obtained in step 6 into the high-frequency event simulation calculation of wind power participating in frequency regulation to obtain the grid frequency curve; 3-8 Obtain the evaluation index value; 3-9 Substitute the evaluation index value into the objective function for calculation, retain the solution with a smaller objective function value, and discard the solution with a larger objective function value; 3-10 Continue to let the wolf pack surround and attack the prey, and update the wolf pack's position; 3-11 Update candidate solutions; 3-12 Termination criteria: if the maximum allowed number of iterations is reached or the objective function value has not improved after multiple consecutive iterations, the calculation is stopped, the results are output, and the optimal cutting amount is obtained; 3-13 If the termination criteria are not met, repeat the above steps to continue the calculation.

4. A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation according to claim 1, characterized in that: The process of building a wind turbine participating in the grid frequency regulation model in the grid simulation software and inputting relevant parameters to simulate the high-frequency events of the grid is as follows: a. Build a regional power grid model in the power system simulation software and construct a scenario where wind turbines participate in power grid frequency regulation; b. In the simulation software, build the wind turbine and related electrical component models according to the actual situation of the regional power grid, and set the parameters of each component; c. Set the power system operation mode; d. Set high-frequency event faults; e. Conduct high-frequency event tests considering wind power participating in frequency regulation, and perform high-frequency unit removal calculations based on the unit removal plan when wind power does not participate in frequency regulation to obtain the grid frequency change trajectory.

5. A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation according to claim 1, characterized in that: The above-mentioned optimization of the capacity of the removed units under the grid frequency regulation of wind power based on the gray wolf optimization algorithm, and the calculation of the unit removal according to the current proportion of wind power units participating in the grid frequency regulation, so that the objective function reaches a smaller value means: a. Randomly initialize the wolf group, obtain the initial value, and calculate the fitness value of each gray wolf; b. Surround, hunt and attack prey to complete the movement of the wolf pack; c. Update the position of the gray wolf, calculate the fitness value, and obtain the candidate solution; d. Set the operation mode and fault conditions in the simulation model; e. Substitute the candidate solution into the wind power frequency regulation simulation model for calculation, that is, modify the cutting amount in the model for simulation: f. Obtain the grid frequency trajectory and record the evaluation indicators; g. Substitute the objective function for calculation, obtain the objective function value, and compare it with the objective function value in the previous iteration result. The one with the smaller objective function value will enter the next iteration, and the one with the larger objective function value will be discarded; h. Repeat the above steps. If the maximum allowed number of iterations is reached or the objective function value has not improved after multiple consecutive iterative calculations, stop the calculation, output the results, and obtain the optimal load reduction.

6. A high-frequency dynamic defense strategy for power grid considering wind power participation in frequency modulation according to claim 1, characterized in that: The adjustment of the wind-fire ratio in the power grid model so that more wind turbines participate in frequency modulation and the calculation again to obtain the high-frequency dynamic defense strategy of the power grid under different wind-fire ratios is: a. Query the units currently in operation in the component setting section of the power grid simulation system flow section; b. Find the unit output summary table; c. Calculate the capacity ratio of wind turbines and thermal power units put into operation under the current operating status; d. Ensure that the total output of the system units remains unchanged, enter the parameter library, and modify the number of wind turbines and thermal power units to be started and stopped; e. Carry out the flow quantity under this operation mode, output the report, and confirm that the wind-fire ratio has been modified; f. Complete the high-frequency cutting calculation under the new wind-fire ratio according to the security control cutting steps under high-frequency events and the above-mentioned optimization algorithm steps; g. Obtain the optimized generator cutting capacity under the new wind-fire ratio, which is used for the high-frequency dynamic defense strategy under the consideration of wind power participating in grid frequency regulation.

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