Self-adaptive cooperative frequency support control method considering severity of disturbance event

Abstract

The invention discloses a self-adaptive cooperative frequency support control method considering the severity of a disturbance event, and belongs to the field of electric power safe operation, and the method comprises the following steps: S1, determining an initial cooperative coefficient based on a capacity ratio and a comprehensive frequency modulation margin factor; s2, judging an operation scene based on a comparison result of the frequency modulation power allocated to each wind power plant and the sum of maximum allowable output power of all wind turbine generators in the wind power plant; s3, fan group cooperation coefficient correction in a conventional scene; s4, carrying out secondary correction on the cooperation coefficients of part of the wind power plants in the extreme operation scene; and S5, the corrected cooperation coefficients of all the wind power plants are obtained. By adopting the adaptive cooperative frequency support control method considering the severity of the disturbance event, the difference between the severity of the disturbance event and the frequency modulation capability is quantitatively evaluated, adaptive dynamic adjustment of the cooperative coefficient from a conventional scene to an extreme scene is realized, and the frequency stability and the anti-disturbance capability of a high-proportion wind power system are improved.

Description

Technical Field

[0001] This invention relates to the field of power safety operation technology, and in particular to an adaptive cooperative frequency support control method that takes into account the severity of disturbance events. Background Technology

[0002] In power systems with a high proportion of wind power integration, wind farm clusters are large in scale and their internal turbine operating conditions vary significantly. Traditional frequency regulation control methods are insufficient to cope with extreme disturbances. When the system experiences a large power deficit (such as a sudden increase of 540MW load), traditional strategies lack a secondary adjustment mechanism, which can easily lead to multiple wind farms exceeding limits simultaneously, exacerbating the risk of frequency collapse. Furthermore, the lack of quantitative assessment of the frequency regulation capability boundaries of wind turbines makes it impossible to define the applicable range of the coordination coefficient, resulting in reduced reliability of the control strategy under large disturbances. Summary of the Invention

[0003] The purpose of this invention is to provide an adaptive cooperative frequency support control method that takes into account the severity of disturbance events, thereby solving the above-mentioned technical problems.

[0004] To achieve the above objectives, the present invention provides an adaptive cooperative frequency support control method that considers the severity of disturbance events, comprising the following steps:

[0005] S1. Obtain the comprehensive frequency regulation margin factor ratio, capacity information, disturbance power and critical disturbance power of each wind farm, and determine the initial coordination coefficient based on the capacity ratio and comprehensive frequency regulation margin factor.

[0006] S2. Based on the comparison between the frequency regulation power allocated to each wind farm and the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, determine its operating scenario.

[0007] When the frequency regulation power allocated to each wind farm is less than or equal to the sum of the maximum allowable output power of all wind turbines in that wind farm under physical constraints, it is determined to be a normal scenario, and step S3 is executed.

[0008] When the frequency regulation power allocated to a part of the wind farm is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be an extreme operating scenario, and step S4 is executed.

[0009] When the frequency regulation power allocated to all wind farms is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be a full extreme scenario, and step S5 is executed.

[0010] S3, Correction of wind turbine group coordination coefficient in conventional scenarios;

[0011] S31. Calculate the safety margin factor of each wind turbine group in the wind farm, and determine whether each wind turbine group has the ability to perform frequency regulation according to the initial coordination coefficient based on the comparison result of the safety margin factor and the initial coordination coefficient. If so, determine that the current wind turbine group is a wind turbine group that has not exceeded the limit and control it according to the initial coordination coefficient. Otherwise, determine that the current wind turbine group is a wind turbine group that has exceeded the limit and execute step S32.

[0012] S32. Set the output power of one of the over-limit wind turbine groups to the maximum allowable output power, output the maximum allowable coordination coefficient, and update the remaining frequency regulation power;

[0013] S33. The remaining over-limit wind turbine group redistributes the remaining frequency regulation power according to the capacity ratio and corrects the initial coordination coefficient;

[0014] S34. Determine the rationality of the corrected initial coordination coefficient. If it is reasonable, output the corrected initial coordination coefficient. Otherwise, return to step S32 and set the output power of another over-limit wind turbine group to the maximum allowable output power.

[0015] S4. Secondary correction of the coordination coefficient of some wind farms under extreme operating scenarios;

[0016] S41. When at least one wind farm is allocated frequency regulation power exceeding the upper limit of frequency regulation capacity of the wind farm under the current operating conditions, all wind farms that have reached the upper limit of frequency regulation capacity shall output at their maximum power, and the corrected coordination coefficient described in S33 shall be used to calculate the secondary allocation of frequency regulation power and the relative safe operating margin of wind farms that have not reached the upper limit of frequency regulation capacity.

[0017] S42. Sort the relative safe operating margins in descending order, and select the wind farms corresponding to the safe operating margins in descending order as reserve sites to undertake secondary distribution of frequency regulation power, and calculate the secondary correction value of their coordination coefficient.

[0018] S43. Compare the safety margin with the second correction value of the coordination coefficient. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, proceed to step S44.

[0019] S44. Use step S33 to correct the second correction value of the coordination coefficient again, and compare the second correction value of the coordination coefficient with the safety margin. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, execute step S5.

[0020] S5. In all extreme scenarios, all wind farms adopt the modified coordination coefficient described in S33 and output power according to the maximum allowable output power.

[0021] In practical frequency support control, the disturbance power is generally unknown, but it can be estimated using the system's average frequency change rate. Therefore, the adaptive cooperative frequency support control method that considers the severity of disturbance events, as described above, has the following beneficial effects:

[0022] 1. Extreme disturbance response capability: Through a scenario-based (normal / extreme / all-extreme) collaborative coefficient adjustment mechanism, it solves the problem of multiple wind farms exceeding limits simultaneously when there is a shortage of high power, thus reducing the risk of frequency collapse;

[0023] 2. Accurate assessment of frequency regulation capability: Introducing the Safety Operation Margin Factor (SOF) to quantify the frequency regulation capability boundary of the wind turbine group, avoiding wind turbines operating beyond their limits due to unreasonable coordination coefficients;

[0024] 3. Dynamic adaptive adjustment based on the severity of disturbance events: based on the disturbance power prediction of the system's average frequency change rate, the coordination coefficient is corrected through cyclic evaluation in normal scenarios, and the power is redistributed according to the relative safety margin in extreme scenarios to ensure efficient utilization of frequency modulation resources;

[0025] 4. Improved system stability: By constraining the safety margin of the wind turbine group and dynamically correcting the coordination coefficient, the frequency dip is reduced, ensuring the safe operation of the power system.

[0026] The technical solution of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. Attached Figure Description

[0027] Figure 1 This is a flowchart of the adaptive cooperative frequency support control method that considers the severity of disturbance events as described in this invention;

[0028] Figure 2 This is a topology diagram of the improved multi-wind farm 4-unit 13-node example described in the verification example of the present invention;

[0029] Figure 3 The simulation results (WF1-[75,75,150]) of the load surge of 432MW under different criteria described in the verification example of the present invention are shown in the figure. (a) is the system frequency change curve, (b) is the total output change curve of each wind farm, and (c) is the wind turbine group speed result of each wind farm.

[0030] Figure 4 The simulation results (WF1-[25,25,250]) of the load surge of 432MW under different criteria described in the verification example of the present invention are shown in (a) the system frequency change curve, (b) the total output change curve of each wind farm, and (c) the wind turbine group speed results of each wind farm. Detailed Implementation

[0031] To make the objectives, technical solutions, and advantages of the embodiments of the present invention clearer, the embodiments of the present invention will be further described in detail below with reference to the accompanying drawings and examples. It should be understood that the specific embodiments described herein are merely illustrative of the embodiments of the present invention and are not intended to limit the embodiments of the present invention. All other embodiments obtained by those skilled in the art based on the embodiments of the present invention without creative effort are within the scope of protection of this application. Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout.

[0032] It should be noted that the terms "comprising" and "having," and any variations thereof, are intended to cover non-exclusive inclusion, such as a process, method, system, product, or server that includes a series of steps or units, not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such process, method, product, or device.

[0033] The embodiments of the present invention will now be described in detail with reference to the accompanying drawings.

[0034] like Figure 1 As shown, the adaptive cooperative frequency support control method considering the severity of disturbance events includes the following steps:

[0035] S1. Obtain the comprehensive frequency regulation margin factor ratio, capacity information, disturbance power and critical disturbance power of each wind farm, and determine the initial coordination coefficient based on the capacity ratio and comprehensive frequency regulation margin factor.

[0036] The expression for the initial synergy coefficient mentioned in step S1 is as follows:

[0037]

[0038] In the formula, OMF represents the initial coordination coefficient of the i-th wind turbine group within the j-th wind farm; FM,j denoted as the j-th integrated frequency regulation margin factor; C represents the collaborative allocation coefficient of the wind farm cluster; N represents the rated capacity of the wind turbine group within the j-th wind farm; sum This indicates the total number of wind farms participating in coordinated frequency regulation.

[0039] S2. Based on the comparison between the frequency regulation power allocated to each wind farm and the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, determine its operating scenario.

[0040] When the frequency regulation power allocated to each wind farm is less than or equal to the sum of the maximum allowable output power of all wind turbines in that wind farm under physical constraints, it is determined to be a normal scenario, and step S3 is executed.

[0041] When the frequency regulation power allocated to a part of the wind farm is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be an extreme operating scenario, and step S4 is executed.

[0042] When the frequency regulation power allocated to all wind farms is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be a full extreme scenario, and step S5 is executed.

[0043] S3, Correction of wind turbine group coordination coefficient in conventional scenarios;

[0044] S31. Calculate the safety margin factor of each wind turbine group in the wind farm, and determine whether each wind turbine group has the ability to perform frequency regulation according to the initial coordination coefficient based on the comparison result of the safety margin factor and the initial coordination coefficient. If so, determine that the current wind turbine group is a wind turbine group that has not exceeded the limit and control it according to the initial coordination coefficient. Otherwise, determine that the current wind turbine group is a wind turbine group that has exceeded the limit and execute step S32.

[0045] The formula for calculating the safety margin factor mentioned in step S31 is as follows:

[0046]

[0047] In the formula, This represents the safety margin factor for the i-th wind turbine group within the j-th wind farm. This represents the critical disturbance power of the i-th wind turbine group within the j-th wind farm. The corresponding maximum system frequency deviation; This represents the deviation of the expected minimum frequency point from the optimal system frequency trajectory;

[0048] And the disturbance power ΔP under the optimal system frequency trajectory L and Proportional, and with the ratio set to κ, rewriting formula (2) yields:

[0049]

[0050] In the formula, This represents the maximum system frequency deviation of the i-th wind turbine group within the j-th wind farm;

[0051] when If the current wind turbine group is within limits, it is determined that the current wind turbine group is not exceeding the limits; otherwise, it is determined that the current wind turbine group is exceeding the limits.

[0052] S32. Set the output power of one of the over-limit wind turbine groups to the maximum allowable output power, output the maximum allowable coordination coefficient, and update the remaining frequency regulation power;

[0053] In step S32, the expression for the maximum allowable output power is as follows:

[0054]

[0055] In the formula, k represents the maximum allowable output power of the i-th wind turbine group within the j-th wind farm; F H represents the feedback coefficient; w ω represents the time constant of inertia of the fan rotor. r0 The rotor's rated speed is represented by s; the complex frequency variable of the Laplace transform is represented by k. m Represents the mechanical power fitting coefficient; k t Represents the electric power fitting coefficient;

[0056] Maximum permissible coefficient of coordination The expression is as follows:

[0057]

[0058] The expression for updating the remaining frequency modulation power is as follows:

[0059]

[0060] in,

[0061]

[0062] In the formula, This represents the remaining frequency regulation power of the j-th wind farm after the update in a normal scenario; This represents the capacity percentage of the remaining wind turbine groups in the j-th wind farm, excluding the i-th wind turbine group. This indicates the frequency regulation power command for the wind farm; This represents the baseline coordination coefficient obtained by adjusting the capacity allocation of each wind turbine group; This represents the capacity percentage of the i-th wind turbine group within the j-th wind farm.

[0063] S33. The remaining over-limit wind turbine group redistributes the remaining frequency regulation power according to the capacity ratio and corrects the initial coordination coefficient;

[0064] The formula for correcting the initial synergy coefficient in step S33 is as follows:

[0065]

[0066] In the formula, This represents the corrected initial synergy coefficient;

[0067] S34. Determine the rationality of the corrected initial coordination coefficient. If it is reasonable, output the corrected initial coordination coefficient. Otherwise, return to step S32 and set the output power of another over-limit wind turbine group to the maximum allowable output power.

[0068] In step S34, if Then the revised initial synergy coefficient is deemed reasonable.

[0069] S4. Secondary correction of the coordination coefficient of some wind farms under extreme operating scenarios;

[0070] S41. When at least one wind farm is allocated frequency regulation power exceeding the upper limit of frequency regulation capacity of the wind farm under the current operating conditions, all wind farms that have reached the upper limit of frequency regulation capacity shall output at their maximum power, and the corrected coordination coefficient described in S33 shall be used to calculate the secondary allocation of frequency regulation power and the relative safe operating margin of wind farms that have not reached the upper limit of frequency regulation capacity.

[0071] In step S41, the following formula is used to determine whether at least one wind farm has been allocated frequency regulation power exceeding the wind farm's frequency regulation capacity limit under the current operating conditions:

[0072]

[0073] Secondary distribution of frequency modulation power The calculation formula is as follows:

[0074]

[0075] in,

[0076]

[0077] In the formula, This represents the remaining frequency regulation power of the j-th wind farm after the update in the extreme scenario;

[0078] Relative safety margin The expression is as follows:

[0079]

[0080] In the formula, This represents the number of remaining wind turbine groups in the j-th wind farm, excluding the i-th wind turbine group.

[0081] S42. Sort the relative safe operating margins in descending order, and select the wind farms corresponding to the safe operating margins in descending order as reserve sites to undertake secondary distribution of frequency regulation power, and calculate the secondary correction value of their coordination coefficient.

[0082] In step S42, the frequency modulation power allocated to the pre-station L is prepared. for:

[0083]

[0084] Substituting formula (11) into formula (13) yields the second-order correction value of the synergy coefficient.

[0085] S43. Compare the safety margin with the second correction value of the coordination coefficient. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, proceed to step S44.

[0086] S44. Use step S33 to correct the second correction value of the coordination coefficient again, and compare the second correction value of the coordination coefficient with the safety margin. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, execute step S5.

[0087] S5. In all extreme scenarios, all wind farms adopt the modified coordination coefficient described in S33 and output power according to the maximum allowable output power.

[0088] In practical frequency support control, the disturbance power is generally unknown, so it can be estimated using the system's average frequency change rate. From the optimal system frequency trajectory, it can be seen that the system frequency corresponding to the moment wind power participates in frequency regulation is the lowest point of the desired frequency, and the disturbance power is directly proportional to the system's average frequency change rate. Therefore, in step S31, the disturbance power ΔP under the optimal system frequency trajectory... L The expression is as follows:

[0089]

[0090] In the formula, ΔP L and These represent the disturbance power and the deviation from the minimum desired frequency point under the optimal system frequency trajectory predicted based on the system's average frequency change rate, respectively; f i ti represents the system frequency detected at the i-th wind farm; t0 represents the time of the disturbance; ΔT represents the duration of the period during which the average frequency change rate is detected; ti represents the frequency of the system detected at the i-th wind farm. A This refers to the moment when wind power participates in frequency regulation.

[0091] Verification Example

[0092] In this verification example, based on such Figure 2The improved 4-turbine 13-node example with multiple wind farms shown verifies the effectiveness of the invention. The system includes three synchronous turbines and three wind farms: WF1, WF2, and WF3. Wind farms WF1 and WF3 are each replaced by a group of three wind turbines, while wind farm WF2 is replaced by a group of two wind turbines. The number of turbines in the three wind farms are 300, 200, and 100 respectively. Detailed turbine parameters are shown in Table 1.

[0093] Table 1 Wind Turbine Parameters

[0094]

[0095] Table 2 Wind speed and number of wind turbines at each wind farm

[0096]

[0097] The system is set to handle a 432MW (24% of total load) load surge event at 2 seconds. Frequency regulation power allocation for wind farms and their turbines is based on the criteria shown in Table 3. The calculated proportion of frequency regulation power undertaken by each wind farm and the corresponding equivalent turbine coordination coefficients are shown in Tables 4 and 5. It can be seen that some coordination coefficients (in bold) are greater than the Safety Operating Margin (SOF), indicating that if the equivalent turbines within their corresponding farms participate in frequency regulation using the current allocation principle, the turbines' physical limits will be triggered.

[0098] Table 3 Description of power allocation criteria for different frequency modulation modes

[0099]

[0100] Table 4. Percentage of Frequency Regulation Power borne by Wind Farms under Different Allocation Criteria

[0101] WF1 WF2 WF3 Guideline 1 0.5 0.333 0.167 Guideline 2 0.465 0.383 0.152 Guideline 3 0.514 0.270 0.216 Guideline 4 0.496 0.376 0.128

[0102] Table 5. Equivalent wind turbine coordination coefficients (WF) under different allocation criteria EQ1 WF EQ2 and WF EQ3 (These represent the coordination coefficients of the first, second, and third wind turbine groups, respectively.)

[0103]

[0104]

[0105] The simulation results are as follows Figure 3 As shown, in terms of security, a collaborative control strategy based on criterion 1 is adopted, and WF1 in WF1... EQ3Triggering speed protection control; the control strategy based on criterion 2 considers the rotor kinetic energy storage of each wind farm and the wind turbine group within the farm, and no secondary frequency drop occurs. However, due to insufficient consideration of the wind turbine frequency regulation capacity margin, the output power of some equivalent wind turbines in the farm triggers the frequency regulation power limit, thus limiting the frequency regulation capability; the control strategy based on criterion 3 comprehensively considers the capacity and wind speed of each wind farm and the wind turbine group within the farm, but there are still unreasonable power distribution issues, WF1 in WF EQ1 WF EQ2 and WF EQ3 The speed protection and frequency regulation power limit were triggered respectively. The proposed adaptive adjustment criterion can ensure that each unit in the station avoids triggering the physical limit. In addition, the wind turbine group that may trigger the physical limit constraint under different criteria obtained by theoretical calculation is consistent with the simulation results, indicating that the rationality evaluation formula (formula (8)) proposed in this application can accurately judge the rationality of the coordination coefficient set according to different allocation criteria in advance.

[0106] Depend on Figure 3 It is evident that the improvement effect on system frequency varies due to the differences in frequency regulation power distribution among the internal units of the station equipment under different criteria. The lowest system frequency point is 49.489Hz for criterion 1, 49.494Hz for criterion 2, and 49.505Hz for criterion 3. The lowest system frequency point using criterion 4 adopted in this application is increased to 49.513Hz, representing improvements of 0.024Hz and 0.019Hz respectively compared to criterion 1 and criterion 2, and an improvement of 0.008Hz compared to criterion 3. Overall, the frequency regulation effect and safety achieved by the proposed adaptive adjustment criterion in this application are superior.

[0107] Table 6. Maximum active power output P of equivalent wind turbine under different criteria. we,max Electromagnetic torque T e,max And the power P of the machine-side converter r,max

[0108]

[0109] To further illustrate the superiority and robustness of the proposed criterion, the number of wind turbines at each wind speed in test scenario WF1 was modified to [25, 25, 250]. In this scenario, the operating conditions of WF1 are more severe, primarily involving wind turbines operating at low to medium wind speeds. A 432MW load surge event was also set at t=2s, and the simulation results are as follows: Figure 4 As shown.

[0110] Depend on Figure 4It is evident that, in terms of safety, the coordinated control based on other allocation criteria all resulted in the equivalent wind turbine speed exceeding the safety threshold, leading to a secondary frequency drop. However, the criterion proposed in this application ensures the safe and stable operation of the unit. Regarding frequency regulation effectiveness, the lowest system frequency for criterion 1 is 49.455Hz, for criterion 2 it is 49.442Hz, and for criterion 3 it is 49.482Hz. The coordinated control strategy using the criterion proposed in this application can raise the lowest frequency point to 49.519Hz, representing increases of 0.064Hz, 0.077Hz, and 0.037Hz respectively compared to criterions 1, 2, and 3. This demonstrates that the adaptive adjustment criterion proposed in this application can adjust power allocation according to the wind farm's operating conditions and tune the coordination coefficient, fully leveraging the wind power frequency regulation potential to improve system frequency response characteristics. Its frequency improvement effect and safety are optimal in different scenarios, verifying the effectiveness of the adaptive adjustment criterion and coordinated control strategy proposed in this application.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit them. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the technical solutions of the present invention, and these modifications or equivalent substitutions cannot cause the modified technical solutions to deviate from the spirit and scope of the technical solutions of the present invention.

Claims

1. An adaptive cooperative frequency support control method considering the severity of disturbance events, characterized in that: Includes the following steps: S1. Obtain the comprehensive frequency regulation margin factor ratio, capacity information, disturbance power and critical disturbance power of each wind farm, and determine the initial coordination coefficient based on the capacity ratio and comprehensive frequency regulation margin factor. S2. Based on the comparison between the frequency regulation power allocated to each wind farm and the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, determine its operating scenario. When the frequency regulation power allocated to each wind farm is less than or equal to the sum of the maximum allowable output power of all wind turbines in that wind farm under physical constraints, it is determined to be a normal scenario, and step S3 is executed. When the frequency regulation power allocated to a part of the wind farm is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be an extreme operating scenario, and step S4 is executed. When the frequency regulation power allocated to all wind farms is greater than the sum of the maximum allowable output power of all wind turbines in the wind farm under physical constraints, it is determined to be a full extreme scenario, and step S5 is executed. S3, Correction of wind turbine group coordination coefficient in conventional scenarios; S31. Calculate the safety margin factor of each wind turbine group in the wind farm, and determine whether each wind turbine group has the ability to perform frequency regulation according to the initial coordination coefficient based on the comparison result of the safety margin factor and the initial coordination coefficient. If so, determine that the current wind turbine group is a wind turbine group that has not exceeded the limit and control it according to the initial coordination coefficient. Otherwise, determine that the current wind turbine group is a wind turbine group that has exceeded the limit and execute step S32. S32. Set the output power of one of the over-limit wind turbine groups to the maximum allowable output power, output the maximum allowable coordination coefficient, and update the remaining frequency regulation power; S33. The remaining over-limit wind turbine group redistributes the remaining frequency regulation power according to the capacity ratio and corrects the initial coordination coefficient; S34. Determine the rationality of the corrected initial coordination coefficient. If it is reasonable, output the corrected initial coordination coefficient. Otherwise, return to step S32 and set the output power of another over-limit wind turbine group to the maximum allowable output power. S4. Secondary correction of the coordination coefficient of some wind farms under extreme operating scenarios; S41. When at least one wind farm is allocated frequency regulation power exceeding the upper limit of frequency regulation capacity of the wind farm under the current operating conditions, all wind farms that have reached the upper limit of frequency regulation capacity shall output at their maximum power, and the corrected coordination coefficient described in S33 shall be used to calculate the secondary allocation of frequency regulation power and the relative safe operating margin of wind farms that have not reached the upper limit of frequency regulation capacity. S42. Sort the relative safe operating margins in descending order, and select the wind farms corresponding to the safe operating margins in descending order as reserve sites to undertake secondary distribution of frequency regulation power, and calculate the secondary correction value of their coordination coefficient. S43. Compare the safety margin with the second correction value of the coordination coefficient. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, proceed to step S44. S44. Use step S33 to correct the second correction value of the coordination coefficient again, and compare the second correction value of the coordination coefficient with the safety margin. If the safety margin is greater than or equal to the second correction value of the coordination coefficient, output the second correction value of the coordination coefficient; otherwise, execute step S5. S5. In all extreme scenarios, all wind farms adopt the modified coordination coefficient described in S33 and output power according to the maximum allowable output power.

2. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 1, characterized in that: The expression for the initial synergy coefficient mentioned in step S1 is as follows: In the formula, OMF represents the initial coordination coefficient of the i-th wind turbine group within the j-th wind farm; FM,j denoted as the j-th integrated frequency regulation margin factor; C represents the collaborative allocation coefficient of the wind farm cluster; N represents the rated capacity of the wind turbine group within the j-th wind farm; sum This indicates the total number of wind farms participating in coordinated frequency regulation.

3. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 2, characterized in that: The formula for calculating the safety margin factor mentioned in step S31 is as follows: In the formula, This represents the safety margin factor for the i-th wind turbine group within the j-th wind farm. This represents the critical disturbance power of the i-th wind turbine group within the j-th wind farm. The corresponding maximum system frequency deviation; This represents the deviation of the expected minimum frequency point from the optimal system frequency trajectory; And the disturbance power ΔP under the optimal system frequency trajectory L and Proportional, and with the ratio set to κ, rewriting formula (2) yields: In the formula, This represents the maximum system frequency deviation of the i-th wind turbine group within the j-th wind farm; when If the current wind turbine group is within limits, it is determined that the current wind turbine group is not exceeding the limits; otherwise, it is determined that the current wind turbine group is exceeding the limits.

4. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 3, characterized in that: In step S32, the expression for the maximum allowable output power is as follows: In the formula, k represents the maximum allowable output power of the i-th wind turbine group within the j-th wind farm; F H represents the feedback coefficient; w ω represents the time constant of inertia of the fan rotor. r0 The rotor's rated speed is represented by s; the complex frequency variable of the Laplace transform is represented by k. m Represents the mechanical power fitting coefficient; k t Represents the electric power fitting coefficient; Maximum permissible coefficient of coordination The expression is as follows: The expression for updating the remaining frequency modulation power is as follows: in, In the formula, This represents the remaining frequency regulation power of the j-th wind farm after the update in a normal scenario; This represents the capacity percentage of the remaining wind turbine groups in the j-th wind farm, excluding the i-th wind turbine group. This indicates the frequency regulation power command for the wind farm; This represents the baseline coordination coefficient obtained by adjusting the capacity allocation of each wind turbine group; This represents the capacity percentage of the i-th wind turbine group within the j-th wind farm.

5. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 4, characterized in that: The formula for correcting the initial synergy coefficient in step S33 is as follows: In the formula, This represents the corrected initial synergy coefficient; In step S34, if Then the revised initial synergy coefficient is deemed reasonable.

6. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 5, characterized in that: In step S41, the following formula is used to determine whether at least one wind farm has been allocated frequency regulation power exceeding the wind farm's frequency regulation capacity limit under the current operating conditions: Secondary distribution of frequency modulation power The calculation formula is as follows: in, In the formula, This represents the remaining frequency regulation power of the j-th wind farm after the update in the extreme scenario; Relative safety margin The expression is as follows: In the formula, This represents the number of remaining wind turbine groups in the j-th wind farm, excluding the i-th wind turbine group.

7. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 6, characterized in that: In step S42, the frequency modulation power allocated to the pre-station L is prepared. for: Substituting formula (11) into formula (13) yields the second-order correction value of the synergy coefficient.

8. The adaptive cooperative frequency support control method considering the severity of disturbance events according to claim 7, characterized in that: In step S31, the disturbance power ΔP under the optimal system frequency trajectory L The expression is as follows: In the formula, ΔP L and These represent the disturbance power and the deviation from the minimum desired frequency point under the optimal system frequency trajectory predicted based on the system's average frequency change rate, respectively; f i ti represents the system frequency detected at the i-th wind farm; t0 represents the time of the disturbance; ΔT represents the duration of the period during which the average frequency change rate is detected; ti represents the frequency of the system detected at the i-th wind farm. A This refers to the moment when wind power participates in frequency regulation.

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