New energy cluster dynamic frequency control method considering communication delay

Abstract

The invention discloses a new energy cluster dynamic frequency control method considering communication delay. The method comprises the following steps: constructing a new energy cluster dynamic model, and obtaining external equivalent characteristics of a new energy cluster to a power transmission network and internal frequency distribution characteristics of the new energy cluster based on the new energy cluster dynamic model; based on the external equivalent characteristic of the new energy cluster to the power transmission network and the internal frequency distribution characteristic of the new energy cluster, obtaining a frequency deviation of a common connection point of the new energy cluster and the power transmission network, and further obtaining a frequency deviation signal and active power injection of the common connection point; the frequency deviation signal and the active power injection jointly form a coordinated feedback signal, and the coordinated feedback signal is input into a local frequency controller to form complete coordinated control. According to the method, the frequency safety of the high-proportion new energy power system can be improved, the frequency overshoot oscillation problem caused by communication delay is reduced, and the frequency regulation capability of a new energy cluster in the power system can be developed.

Description

Technical Field

[0001] This invention belongs to the field of power systems, and specifically relates to a dynamic frequency control method for new energy clusters that takes into account communication delay. Background Technology

[0002] The integration of a high proportion of renewable energy sources poses a severe challenge to maintaining the reliability of the power system. Among these challenges, issues related to frequency stability can lead to serious power system failures, thus creating a demand for flexible resources to participate in grid frequency regulation. However, due to the small capacity, dispersed location, and unstable output of individual flexible resources, they are usually difficult to participate in grid ancillary services as independent entities. By constructing a dynamic model of renewable energy clusters, various types of resources within the grid can be aggregated and uniformly regulated. This enables rapid power allocation and absorption internally, and exhibits aggregation characteristics externally, constructing a new type of grid system with multiple functions such as power control and frequency regulation, providing a feasible approach to solving the aforementioned problems.

[0003] As a means of aggregating flexible resources to participate in power system frequency regulation, the method of constructing dynamic models of renewable energy clusters has been extensively explored in terms of resource aggregation modeling, control strategy design, parameter optimization, and multi-entity coordinated operation, and has been proven to be technically feasible and possess significant system regulation potential. However, most existing studies focus on secondary frequency regulation and longer time scales, while lacking in-depth analysis of the primary frequency regulation process. Furthermore, existing studies are generally based on ideal communication conditions and do not consider the impact of communication delays on the coordinated response performance of multiple types of resources within renewable energy clusters in real-world environments. Summary of the Invention

[0004] To address the shortcomings of existing technologies, the present invention aims to provide a dynamic frequency control method for new energy clusters that takes into account communication delays, thereby improving the frequency security of high-proportion new energy power systems.

[0005] The technical solution adopted in this invention is: a dynamic frequency control method for new energy clusters considering communication delay, comprising: A dynamic model of the new energy cluster is constructed, and the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster are obtained based on the dynamic model of the new energy cluster. Based on the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster, the frequency deviation between the new energy cluster and the power transmission network common connection point is obtained, and then the frequency deviation signal and the active power injection at the common connection point are obtained; the frequency deviation signal and the active power injection together form a coordination feedback signal, which is input into the local frequency controller to form a complete cooperative control.

[0006] Furthermore, a dynamic model for new energy clusters is constructed, specifically as follows: Each resource unit within the new energy cluster is modeled using either a follow-network or a structure-network control method according to its characteristics. Each resource unit within the new energy cluster is connected to the internal network of the new energy cluster through a common coupling point. The entire new energy cluster achieves bidirectional power flow with the main power grid through a common connection point.

[0007] Furthermore, based on the dynamic model of the new energy cluster, the external equivalent characteristics of the new energy cluster to the transmission network are obtained, specifically: The amount of active power deficit that needs to be compensated by network-connected and network-building equipment is equivalent to the product of the transfer function of each network-connected and network-building equipment and the frequency change of the common connection point. When a transient frequency event occurs in the power system, the total active power deficit that the entire new energy cluster needs to make up is the sum of the active power deficits that the grid-connected equipment and the grid-building equipment need to make up.

[0008] Furthermore, the internal frequency distribution characteristics of the new energy cluster are as follows: The frequency distribution of each node in the power system of the new energy cluster exhibits a significant linear correlation, and the distribution pattern is mainly determined by the electrical distance between each node in the power system. Under a simplified network model that ignores line resistance, there is a clear correlation between frequency distribution and the self-susceptance of the bus node, as well as the transferred reactance of the connected new energy node and generator node.

[0009] Furthermore, based on the external equivalent characteristics of the renewable energy cluster to the transmission network and the internal frequency distribution characteristics of the renewable energy cluster, the frequency deviation between the renewable energy cluster and the transmission network's point of common coupling is obtained, thereby obtaining the frequency deviation signal and the active power injection at the point of common coupling; specifically: During steady-state operation, the active power injection is set by the transmission system operator based on the electricity market demand, and at this time the system frequency deviation at the point of common coupling is zero, the local frequency deviation is also zero, and the feedback control of the new energy cluster and the local frequency controller of the flexibility resources are not activated. During non-steady-state operation, the active power injection will switch to the real-time measurement value of the power exchanged between the new energy cluster and the main grid. The system frequency deviation at the common connection point is not zero, which activates the feedback control mechanism. The coordinated feedback signal and the local frequency deviation are introduced to work together on the flexible resource frequency controller of the new energy cluster.

[0010] Furthermore, the frequency deviation signal and the injected active power together form a coordinated feedback signal, which is input into the local frequency controller to form a complete coordinated control; the formula is as follows: In the formula, To coordinate feedback signals, For feedback control, the transfer function is... This refers to the frequency variation signal at the common connection point between the new energy cluster and the power transmission network. Injecting active power; This is the gain coefficient. and These are the lead and lag time constants, respectively. The operators are those after the Laplace transform. The transfer function of the additional damping controller based on the phase compensation principle is given to account for communication delay. This represents the gain coefficient of the damping controller; is the time constant of the filtering stage; n is the number of compensation stages, which is 2 in this invention.

[0011] Furthermore, the additional damping controller based on the phase compensation principle mainly consists of a gain stage, a filtering stage, a phase compensation stage, and a limiting stage, which takes the frequency deviation signal as input and acts on the coordination feedback signal.

[0012] Furthermore, based on the different dynamic response characteristics and frequency regulation capabilities of various types of resources within the new energy cluster, the coordinated feedback signals allocated to the frequency controllers of different flexible resources within the new energy cluster are as follows: In the formula, For the coordination feedback signal allocated to the k-th flexibility resource frequency controller; Let be the coordination feedback signal allocation coefficient in the k-th flexibility resource frequency controller.

[0013] Furthermore, the coordination feedback signal allocation coefficients are obtained through optimization using the Grey Wolf algorithm; specifically: The objective function is constructed after normalization, using the maximum frequency deviation and frequency change rate as safety indicators. The formula is as follows: In the formula, , These represent the proportions of the maximum frequency deviation and the rate of frequency change, respectively. This represents the maximum frequency deviation. The frequency change rate is taken as the value 0.5s after the transient frequency event. and These are the safety threshold values ​​for the maximum frequency deviation and the rate of frequency change, respectively. The constraints of the objective function are as follows: In the formula, This is the minimum value of the maximum frequency deviation. The maximum value of the maximum frequency deviation. This is the minimum value of the rate of change of frequency. This represents the maximum value of the rate of change of frequency. For the first The change in output power of a flexible resource; , The first The upper and lower limits of the adjustment capacity of a flexible resource; Let k be the adjustment rate of the k-th flexibility resource; , These are the upper and lower limits of the adjustment rate for the k-th flexibility resource, respectively. Let be the transfer function for the k-th flexibility resource; The input signal for the frequency controller of the flexible resource of the new energy cluster; The total active power deficit that needs to be supplemented for the new energy cluster; m is the total number of flexible resources; and These are the maximum and minimum values ​​of the allocation coefficients for the coordinated feedback signal, respectively.

[0014] Furthermore, the input signal of the flexibility resource frequency controller of the new energy cluster is given by the following formula: In the formula, For the frequency deviation measured on the local bus, This is a frequency reference value. Let be the frequency of the k-th flexibility resource on the local bus.

[0015] The beneficial effects of this invention are as follows: This invention designs an additional damping controller based on the phase compensation principle to suppress the impact of communication delay.

[0016] This invention can improve the frequency security of high-proportion renewable energy power systems, reduce frequency overshoot oscillation problems caused by communication delays, and help to give full play to the frequency regulation capabilities of renewable energy clusters in power systems. Attached Figure Description

[0017] Figure 1 This is a structural diagram of the dynamic model of the new energy cluster.

[0018] Figure 2 This is a control block diagram for coordinated control.

[0019] Figure 3 This is a structural diagram of the additional damping controller. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this application clearer, the application is described and illustrated below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application. All other embodiments obtained by those skilled in the art based on the embodiments provided in this application without inventive effort are within the scope of protection of this application.

[0021] This invention provides a dynamic frequency control method for new energy clusters that takes into account communication delay. To make the above-mentioned objectives, features and advantages of this invention more apparent and understandable, the invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0022] A dynamic model of the new energy cluster is constructed, and the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster are obtained based on the dynamic model of the new energy cluster. Based on the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster, the frequency deviation between the new energy cluster and the power transmission network common connection point is obtained, and then the frequency deviation signal and the active power injection at the common connection point are obtained; the frequency deviation signal and the active power injection together form a coordination feedback signal, which is input into the local frequency controller to form a complete cooperative control.

[0023] Furthermore, a dynamic model for new energy clusters is constructed, specifically as follows: Each resource unit within the new energy cluster is modeled using either a follow-network or a structure-network control method according to its characteristics. Each resource unit within the new energy cluster is connected to the internal network of the new energy cluster through a common coupling point. The entire new energy cluster achieves bidirectional power flow with the main power grid through a common connection point.

[0024] Furthermore, based on the dynamic model of the new energy cluster, the external equivalent characteristics of the new energy cluster to the transmission network are obtained, specifically: The amount of active power deficit that needs to be compensated by network-connected and network-building equipment is equivalent to the product of the transfer function of each network-connected and network-building equipment and the frequency change of the common connection point. When a transient frequency event occurs in the power system, the total active power deficit that the entire new energy cluster needs to make up is the sum of the active power deficits that the grid-connected equipment and the grid-building equipment need to make up.

[0025] Furthermore, the internal frequency distribution characteristics of the new energy cluster are as follows: The frequency distribution of each node in the power system of the new energy cluster exhibits a significant linear correlation, and the distribution pattern is mainly determined by the electrical distance between each node in the power system. Under a simplified network model that ignores line resistance, there is a clear correlation between frequency distribution and the self-susceptance of the bus node, as well as the transferred reactance of the connected new energy node and generator node.

[0026] like Figure 1 As shown, the dynamic model structure of the new energy cluster mainly adopts a centralized control architecture, and divides the internal flexibility resources into two categories: grid-forming (GFM) control and grid-following (GFL) control.

[0027] The wind and photovoltaic power generation units are configured in GFL control mode, primarily for grid integration and consumption of new energy, while the energy storage system uniformly adopts GFM control mode, mainly for grid support. Each resource unit within the new energy cluster connects to the internal network of the new energy cluster system through a Point of Common Coupling (PCC). The entire new energy cluster achieves bidirectional power flow with the main grid through a Point of Connection (POC). Furthermore, a control center is established, which acquires two types of key data in real time based on synchronous phasor measurement units (PMUs) via a bidirectional communication network: one is the overall operating status information of the new energy cluster at the POC; the other is the local operating status of each resource unit within the new energy cluster.

[0028] Network control modeling is implemented as follows: The grid-synchronized control process with additional frequency control achieves grid synchronization through a phase-locked loop (PLL), enabling precise control of active and reactive power by controlling the current component. The dynamic relationship of the PLL can be described as follows: the PLL's output frequency is determined by the grid frequency deviation adjusted by a PI controller, combined with the q-axis component of the voltage at the PCC. This frequency deviation is defined as the difference between the actual grid frequency and the PLL's output frequency. The proportional and integral terms of the PI controller are handled by controller coefficients. The output phase is updated synchronously with the dynamic adjustment of the frequency.

[0029] In grid-based control, the phase angle of the voltage at the PCC is used as a reference. The phase at the POC in the renewable energy cluster is related to the output phase of the phase-locked loop. The active and reactive power transmitted from the renewable energy cluster to the POC can be derived from the voltage at the PCC, the d-axis and q-axis components of the converter output current, and the circuit power calculation principle.

[0030] Network-based control modeling is achieved through the following: Unlike grid-based control, which relies on a phase-locked loop (PLL) to track the grid phase, grid-based control abandons this external synchronization mechanism. Instead, it constructs its internal active power control loop based on the rotor swing equation of the synchronous generator, thus directly simulating the inertial response and damping characteristics of the synchronous rotor under varying power angles. The dynamic relationship of the active power control loop in grid-based control can be described as follows: the product of the inertia coefficient and the rate of change of the virtual synchronous generator (VSG) control output frequency equals the difference between the product of the active power reference value and the droop coefficient, minus the product of the damping coefficient and the difference between the frequency reference value and the VSG control output frequency.

[0031] The system impedance is set to be purely inductive, with the PCC voltage phase as a reference. The active and reactive power delivered by the grid-connected converter to the POC are determined by the output voltage amplitude of the grid-connected converter, the connection reactance between the grid-connected converter and the POC, and the phase difference between the voltages at both ends.

[0032] As can be seen from the above modeling process, the renewable energy cluster is connected to the main grid through the Point of Conversion (POC). Therefore, from the perspective of the main grid, the grid connection characteristics of the renewable energy cluster are characterized by the equivalent external characteristics of the POC, rather than the operational characteristics of the various flexible resources within the renewable energy cluster. When a transient event occurs in the power system, the control process of the renewable energy cluster can be expressed as follows: When a transient frequency disturbance occurs in the power system, the total active power support required by the renewable energy cluster is the sum of the active power deficits that all grid-connected and grid-building equipment within the renewable energy cluster need to make up; the active power increment of each grid-connected equipment is generated by the frequency deviation of the POC through its corresponding control transfer function; the active power increment of each grid-building equipment is generated by the same frequency deviation through its own control transfer function.

[0033] Furthermore, based on the external equivalent characteristics of the renewable energy cluster to the transmission network and the internal frequency distribution characteristics of the renewable energy cluster, the frequency deviation between the renewable energy cluster and the transmission network's point of common coupling is obtained, thereby obtaining the frequency deviation signal and the active power injection at the point of common coupling; specifically: During steady-state operation, the active power injection is set by the transmission system operator based on the electricity market demand, and at this time the system frequency deviation at the point of common coupling is zero, the local frequency deviation is also zero, and the feedback control of the new energy cluster and the local frequency controller of the flexibility resources are not activated. During non-steady-state operation, the active power injection will switch to the real-time measurement value of the power exchanged between the new energy cluster and the main grid. The system frequency deviation at the common connection point is not zero, which activates the feedback control mechanism. The coordinated feedback signal and the local frequency deviation are introduced to work together on the flexible resource frequency controller of the new energy cluster.

[0034] like Figure 2As shown, the frequency deviation signal and the active power injection together form a coordination feedback signal, which is input to the local frequency controller to form a complete cooperative control; the formula is as follows: In the formula, To coordinate feedback signals, For feedback control, the transfer function is... This refers to the frequency variation signal at the common connection point between the new energy cluster and the power transmission network. Injecting active power; This is the gain coefficient. and These are the lead and lag time constants, respectively. The operators are those after the Laplace transform. The transfer function of the additional damping controller based on the phase compensation principle is given to account for communication delay. This represents the gain coefficient of the damping controller; is the time constant of the filtering stage; n is the number of compensation stages, which is 2 in this invention.

[0035] Furthermore, the additional damping controller based on the phase compensation principle mainly consists of a gain stage, a filtering stage, a phase compensation stage, and a limiting stage, which takes the frequency deviation signal as input and acts on the coordination feedback signal.

[0036] Furthermore, based on the different dynamic response characteristics and frequency regulation capabilities of various types of resources within the new energy cluster, the coordinated feedback signals allocated to the frequency controllers of different flexible resources within the new energy cluster are as follows: In the formula, For the coordination feedback signal allocated to the k-th flexibility resource frequency controller; Let be the coordination feedback signal allocation coefficient in the k-th flexibility resource frequency controller.

[0037] Among them, when the types of flexibility resources are different, the definition is as follows: Define the coordination feedback signal allocated to the GFL control. For the coordination feedback signal allocated to the GFM control; The coordination feedback signal allocation coefficient in the frequency controller of the k-th flexibility resource is defined as follows: [Definition missing - likely a typo]. Define the coordination feedback signal allocation coefficients assigned to GFL control. The allocation coefficients are used for the coordination feedback signals assigned to the GFM control.

[0038] Furthermore, the coordination feedback signal allocation coefficients are obtained through optimization using the Grey Wolf algorithm; specifically: The objective function is constructed after normalization, using the maximum frequency deviation and frequency change rate as safety indicators. The formula is as follows: In the formula, , These represent the proportions of the maximum frequency deviation and the rate of frequency change, respectively. This represents the maximum frequency deviation. The frequency change rate is taken as the value 0.5s after the transient frequency event. and These are the safety threshold values ​​for the maximum frequency deviation and the rate of frequency change, respectively. The constraints of the objective function are as follows: In the formula, This is the minimum value of the maximum frequency deviation. The maximum value of the maximum frequency deviation. This is the minimum value of the rate of change of frequency. This represents the maximum value of the rate of change of frequency. For the first The change in output power of a flexible resource; , The first The upper and lower limits of the adjustment capacity of a flexible resource; Let k be the adjustment rate of the k-th flexibility resource; , These are the upper and lower limits of the adjustment rate for the k-th flexibility resource, respectively. Let be the transfer function for the k-th flexibility resource; The input signal for the frequency controller of the flexible resource of the new energy cluster; The total active power deficit that needs to be supplemented for the new energy cluster; m is the total number of flexible resources; and These are the maximum and minimum values ​​of the allocation coefficients for the coordinated feedback signal, respectively.

[0039] Furthermore, the input signal of the flexibility resource frequency controller of the new energy cluster is given by the following formula: In the formula, For the frequency deviation measured on the local bus, This is a frequency reference value. The frequency of the k-th flexibility resource on the local bus is determined by the different control types of GFL and GFM, and is set to a value accordingly. or .

[0040] like Figure 3 As shown, the additional damping controller mainly consists of a gain stage, a filtering stage, a phase compensation stage, and a limiting stage. The gain stage adjusts the amplitude of the input signal, directly determining the strength of the damping effect. The filtering stage extracts oscillation signals within a specific frequency band, ensuring the controller only responds to dynamic processes within the target frequency range. The lead-lag stage (phase compensation stage) provides precise phase compensation, adjusting the phase characteristics of the control signal to ensure it ultimately provides positive damping to the power system. The limiting stage constrains the amplitude of the output signal, preventing over-adjustment or overshoot and ensuring stable equipment operation. When the power system detects oscillations, the controller generates a corresponding damping control signal and superimposes this signal onto the converter's active power injection control loop. Ultimately, this drives the generator set to output damping power with a phase opposite to the oscillation, thereby offsetting power oscillations in the power system and improving the overall damping level and transient stability of the power system.

[0041] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A dynamic frequency control method for new energy clusters considering communication delay, characterized in that, include: A dynamic model of the new energy cluster is constructed, and the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster are obtained based on the dynamic model of the new energy cluster. Based on the external equivalent characteristics of the new energy cluster to the power transmission network and the internal frequency distribution characteristics of the new energy cluster, the frequency deviation between the new energy cluster and the power transmission network common connection point is obtained, and then the frequency deviation signal and the active power injection at the common connection point are obtained; the frequency deviation signal and the active power injection together form a coordination feedback signal, which is input into the local frequency controller to form a complete cooperative control.

2. The dynamic frequency control method for new energy clusters considering communication delay according to claim 1, characterized in that, Constructing a dynamic model for new energy clusters, specifically: Each resource unit within the new energy cluster is modeled using either a follow-network or a structure-network control method according to its characteristics. Each resource unit within the new energy cluster is connected to the internal network of the new energy cluster through a common coupling point. The entire new energy cluster achieves bidirectional power flow with the main power grid through a common connection point.

3. The dynamic frequency control method for new energy clusters considering communication delay according to claim 1, characterized in that, Based on the dynamic model of the new energy cluster, the external equivalent characteristics of the new energy cluster to the power transmission network are obtained, specifically: The amount of active power deficit that needs to be compensated by network-connected and network-building equipment is equivalent to the product of the transfer function of each network-connected and network-building equipment and the frequency change of the common connection point. When a transient frequency event occurs in the power system, the total active power deficit that the entire new energy cluster needs to make up is the sum of the active power deficits that the grid-connected equipment and the grid-building equipment need to make up.

4. The dynamic frequency control method for new energy clusters considering communication delay according to claim 1, characterized in that, The internal frequency distribution characteristics of the new energy cluster are as follows: The frequency distribution of each node in the power system of the new energy cluster exhibits a significant linear correlation, and the distribution pattern is mainly determined by the electrical distance between each node in the power system. Under a simplified network model that ignores line resistance, there is a clear correlation between frequency distribution and the self-susceptance of the bus node, as well as the transferred reactance of the connected new energy node and generator node.

5. The dynamic frequency control method for new energy clusters considering communication delay according to claim 1, characterized in that, Based on the external equivalent characteristics of the renewable energy cluster to the transmission network and the internal frequency distribution characteristics of the renewable energy cluster, the frequency deviation between the renewable energy cluster and the transmission network at the point of common coupling (PCC) is obtained, and thus the frequency deviation signal and the active power injection at the PCC are obtained; specifically: During steady-state operation, the active power injection is set by the transmission system operator based on the electricity market demand, and at this time the system frequency deviation at the point of common coupling is zero, the local frequency deviation is also zero, and the feedback control of the new energy cluster and the local frequency controller of the flexibility resources are not activated. During non-steady-state operation, the active power injection will switch to the real-time measurement value of the power exchanged between the new energy cluster and the main grid. The system frequency deviation at the common connection point is not zero, which activates the feedback control mechanism. The coordinated feedback signal and the local frequency deviation are introduced to work together on the flexible resource frequency controller of the new energy cluster.

6. The dynamic frequency control method for new energy clusters considering communication delay according to claim 1, characterized in that, The frequency deviation signal and the active power injection together form a coordination feedback signal, which is input to the local frequency controller to form a complete cooperative control; the formula is as follows: In the formula, To coordinate feedback signals, For feedback control, the transfer function is... This refers to the frequency variation signal at the common connection point between the new energy cluster and the power transmission network. Injecting active power; This is the gain coefficient. and These are the lead and lag time constants, respectively. The operators are those after the Laplace transform. The transfer function of the additional damping controller based on the phase compensation principle is given to account for communication delay. This represents the gain coefficient of the damping controller; is the time constant of the filtering stage; n is the number of compensation stages, which is 2 in this invention.

7. The dynamic frequency control method for new energy clusters considering communication delay according to claim 6, characterized in that, The additional damping controller based on the phase compensation principle mainly consists of a gain stage, a filtering stage, a phase compensation stage, and a limiting stage. It takes the frequency deviation signal as input and acts on the coordination feedback signal.

8. A dynamic frequency control method for new energy clusters considering communication delay according to claim 6, characterized in that, Based on the different dynamic response characteristics and frequency regulation capabilities of various types of resources within the new energy cluster, the coordinated feedback signal allocated to the frequency controllers of different flexible resources in the new energy cluster is as follows: In the formula, For the coordination feedback signal allocated to the k-th flexibility resource frequency controller; Let be the coordination feedback signal allocation coefficient in the k-th flexibility resource frequency controller.

9. A dynamic frequency control method for new energy clusters considering communication delay according to claim 8, characterized in that, The coordination feedback signal allocation coefficients are obtained through optimization using the Grey Wolf algorithm; specifically: The objective function is constructed after normalization, using the maximum frequency deviation and frequency change rate as safety indicators. The formula is as follows: In the formula, , These represent the proportions of the maximum frequency deviation and the rate of frequency change, respectively. This represents the maximum frequency deviation. The frequency change rate is taken as the value 0.5s after the transient frequency event. and These are the safety threshold values ​​for the maximum frequency deviation and the rate of frequency change, respectively. The constraints of the objective function are as follows: In the formula, This is the minimum value of the maximum frequency deviation. The maximum value of the maximum frequency deviation. This is the minimum value of the rate of change of frequency. This represents the maximum value of the rate of change of frequency. For the first The change in output power of a flexible resource; , The first The upper and lower limits of the adjustment capacity of a flexible resource; Let k be the adjustment rate of the k-th flexibility resource; , These are the upper and lower limits of the adjustment rate for the k-th flexibility resource, respectively. Let be the transfer function for the k-th flexibility resource; The input signal for the frequency controller of the flexible resource of the new energy cluster; To make up for the total active power deficit required by the new energy cluster; m represents the total number of flexible resources; and These are the maximum and minimum values ​​of the allocation coefficients for the coordinated feedback signal, respectively.

10. A dynamic frequency control method for new energy clusters considering communication delay according to claim 9, characterized in that, The input signal of the frequency controller for the flexibility resources of the new energy cluster is given by the following formula: In the formula, For the frequency deviation measured on the local bus, This is a frequency reference value. Let be the frequency of the k-th flexibility resource on the local bus.

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