Flywheel energy storage participates in power grid primary frequency modulation coordination control method and system

Abstract

The application discloses a flywheel energy storage participates in power grid primary frequency modulation coordination control method and system, the method comprises the following steps: establishing a flywheel energy storage auxiliary thermal power unit participating in power grid primary frequency modulation model of equal frequency modulation capacity; determining the power grid frequency deviation, the frequency change rate and the primary frequency modulation instruction according to the power grid frequency value and the thermal power unit modulation difference coefficient; determining the filter time constant according to the power grid frequency change rate and the flywheel SOC and using the fuzzy controller; determining the low-frequency component and the high-frequency component according to the filter time constant, the primary frequency modulation instruction and the low-pass filter; determining the flywheel energy storage system actual output power and the thermal power unit supplementary power according to the high-frequency component, the virtual droop power signal and the first controller and the second controller; determining the thermal power unit actual frequency modulation instruction according to the thermal power unit supplementary power and the low-frequency component. The application can improve the power grid frequency stability and smooth the thermal power unit output.

Description

Technical Field

[0001] This invention relates to the field of power grid frequency regulation, and in particular to a method and system for coordinated control of flywheel energy storage participating in primary frequency regulation of the power grid. Background Technology

[0002] As China accelerates its energy structure transformation, the proportion of renewable energy will further increase, and the power system will gradually transform into a new type of power system. One of the most significant characteristics of this new power system is that the large-scale integration of renewable energy sources such as wind and solar power has rendered previously fully or largely controllable power systems uncontrollable, resulting in significant changes to the attributes and characteristics of the power system. This uncontrollability on the power generation side poses a major challenge to grid frequency security, thus necessitating the introduction of new frequency regulation methods to alleviate the frequency regulation pressure on thermal power units.

[0003] Flywheel energy storage, as a type of energy storage system, possesses advantages such as fast ramp rate, short response time, and frequent charging and discharging capabilities. Using flywheels to assist thermal power units in grid frequency regulation not only improves response speed and regulation accuracy but also ensures that the output power of the thermal power unit does not fluctuate significantly within a short period, saving coal consumption and extending the unit's service life. Therefore, in the current context of emphasizing the flexibility of thermal power units, researching flywheel energy storage systems to assist in the frequency regulation of thermal power units has significant practical and guiding implications.

[0004] Domestic and international scholars have conducted extensive research on energy storage participation in primary frequency regulation control strategies for power grids. Existing research on energy storage control strategies mainly focuses on droop control or virtual inertial control. The frequency regulation commands for energy storage come directly from the grid frequency, meaning there is no coupling between the frequency regulation commands of thermal power units and energy storage. Therefore, the energy storage system cannot handle the high-frequency components in the unit's frequency regulation commands. The increasing proportion of new energy sources and their uncertain output lead to frequent fluctuations in grid frequency, resulting in a corresponding increase in the high-frequency components in thermal power unit frequency regulation commands. The large inertia and delay characteristics of thermal power units make their response speed to loads slow, making it difficult to track the high-frequency components in frequency regulation commands, causing deviations in unit output. Furthermore, responding to high-frequency components in thermal power units leads to frequent unit operations, accelerating the aging of unit equipment. Summary of the Invention

[0005] The purpose of this invention is to provide a method and system for coordinating and controlling the primary frequency regulation of the power grid by flywheel energy storage, which can improve the frequency stability of the power grid and smooth the output of thermal power units.

[0006] To achieve the above objectives, the present invention provides the following solution:

[0007] A method for flywheel energy storage to participate in the primary frequency regulation coordination control of the power grid includes:

[0008] A model for flywheel energy storage with equal frequency regulation capacity to assist thermal power units in participating in the primary frequency regulation of the power grid is established. The model is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the model to characterize the frequency regulation capacity of energy storage replacing thermal power units.

[0009] Obtain the power grid frequency value and the thermal power unit droop coefficient;

[0010] The grid frequency deviation, frequency change rate, and primary frequency regulation command are determined based on the grid frequency value and the thermal power unit droop coefficient.

[0011] Based on the grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and using a fuzzy controller, the filtering time constant is determined.

[0012] The low-frequency and high-frequency components are determined based on the filter time constant, the primary frequency regulation command, and the low-pass filter; the low-frequency component serves as the primary frequency regulation reference command for the thermal power unit; and the high-frequency component serves as an input to the flywheel energy storage system.

[0013] Based on the high-frequency components, the virtual droop power signal, and the first and second controllers that limit the flywheel output using a Logistic regression function with flywheel SOC as the independent variable, the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit are determined.

[0014] The actual frequency regulation command of the thermal power unit is determined based on the supplementary power and low-frequency components of the thermal power unit.

[0015] Frequency regulation is performed based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity participating in the primary frequency regulation model of the power grid.

[0016] Optionally, the determination of the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit based on the first and second controllers that limit the flywheel output power according to the high-frequency components, the virtual droop power signal, and the Logistic regression function with the flywheel SOC as the independent variable, specifically includes:

[0017] The first controller uses a Logistic regression function with flywheel SOC as the independent variable to limit high-frequency components, and determines the supplementary power of the thermal power unit based on the output of the first controller and the high-frequency components.

[0018] The second controller uses the output of the first controller and the virtual droop power signal to determine the theoretical expected power of the flywheel and the flywheel SOC to determine the actual output power of the flywheel energy storage system.

[0019] Optionally, the output of the first controller specifically includes the following formula:

[0020] ;

[0021] Among them, P af1 P is the output of the first controller. d P is the discharge power. c For charging power, P rf1 The input is determined based on the high-frequency components.

[0022] Optionally, when the high-frequency component exceeds the flywheel output margin, the first controller uses a logistic regression function with the flywheel SOC as the independent variable to limit the high-frequency component, and determines the supplementary power of the thermal power unit based on the output of the first controller and the high-frequency component, specifically including:

[0023] Using formula Determine the supplementary power of thermal power units;

[0024] Among them, P b To supplement the power of thermal power units, P H For high-frequency components, P af1 This is the output of the first controller.

[0025] Optionally, determining the actual frequency regulation command of the thermal power unit based on the supplementary power and primary frequency regulation command specifically includes:

[0026] Using formula Determine the actual frequency regulation command for the thermal power unit;

[0027] Among them, P G ’ P is the actual frequency regulation command for thermal power units. L For low-frequency components, P b To supplement the power of thermal power units.

[0028] A flywheel energy storage system participating in primary frequency regulation coordination control of the power grid includes:

[0029] The model building module is used to build a model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid; the model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the model to characterize the frequency regulation capacity of energy storage replacing thermal power units.

[0030] The parameter acquisition module is used to acquire the grid frequency value and the thermal power unit droop coefficient;

[0031] The parameter calculation module is used to determine the grid frequency deviation, frequency change rate, and primary frequency regulation command based on the grid frequency value and the thermal power unit droop coefficient.

[0032] The filter time constant determination module is used to determine the filter time constant based on the grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and by using a fuzzy controller.

[0033] The low-frequency component and high-frequency component determination module is used to determine the low-frequency component and high-frequency component based on the filter time constant, the primary frequency modulation command, and the low-pass filter; the low-frequency component serves as the primary frequency modulation reference command for the thermal power unit; and the high-frequency component serves as an input quantity for the flywheel energy storage system.

[0034] The module for determining the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit is used to determine the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit based on the high-frequency component, the virtual droop power signal, and the first and second controllers that limit the flywheel output power using a Logistic regression function with the flywheel SOC as the independent variable.

[0035] The actual frequency regulation command determination module for thermal power units is used to determine the actual frequency regulation command for thermal power units based on the supplementary power and low-frequency components of the thermal power units.

[0036] The frequency regulation module is used to regulate the frequency of the thermal power unit based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with the same frequency regulation capacity participating in the primary frequency regulation model of the power grid.

[0037] A flywheel energy storage system for coordinating primary frequency regulation in a power grid includes: at least one processor, at least one memory, and computer program instructions stored in the memory, wherein the method is implemented when the computer program instructions are executed by the processor.

[0038] According to specific embodiments provided by the present invention, the present invention discloses the following technical effects:

[0039] This invention provides a method and system for coordinated control of flywheel energy storage participating in primary frequency regulation of the power grid. It establishes a model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity in participating in primary frequency regulation of the power grid, providing a basis for quantitative analysis of the complementary potential of flywheel energy storage for thermal power unit frequency regulation. Based on the power grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and using a fuzzy controller, the filtering time constant is determined. Low-frequency and high-frequency components are determined based on the filtering time constant, primary frequency regulation commands, and a low-pass filter. The primary frequency regulation commands of the thermal power units are decomposed using a low-pass filter with a variable time constant; the high-frequency command signal is transmitted to the flywheel, and the low-frequency signal is transmitted to the thermal power unit. The time constant of the low-pass filter is dynamically adjusted by fuzzy control according to the system frequency change rate and the flywheel SOC based on set fuzzy rules. By adjusting the filtering constant in real time using the flywheel SOC and the system frequency change rate, the output of the thermal power units is effectively smoothed while balancing primary frequency regulation effects and flywheel SOC self-recovery. Attached Figure Description

[0040] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0041] Figure 1 This is a schematic diagram of a method for coordinating and controlling the primary frequency regulation of a power grid using flywheel energy storage, provided by the present invention.

[0042] Figure 2 A schematic diagram of the structure of a flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity participating in the primary frequency regulation of the power grid;

[0043] Figure 3 This is a schematic diagram illustrating the principle of a flywheel energy storage method for participating in primary frequency regulation coordination control of the power grid, provided by the present invention.

[0044] Figure 4 A schematic diagram of the membership function for input and output quantities;

[0045] Figure 5 This is a schematic diagram showing the breakdown of the thermal power command.

[0046] Figure 6 This is a schematic diagram of a flywheel energy storage system. Detailed Implementation

[0047] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0048] The purpose of this invention is to provide a method and system for coordinating and controlling the primary frequency regulation of the power grid by flywheel energy storage, which can improve the frequency stability of the power grid and smooth the output of thermal power units.

[0049] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0050] Figure 1 This is a schematic flowchart of a method for coordinating flywheel energy storage to participate in primary frequency regulation control of a power grid, provided by the present invention. Figure 3 This is a schematic diagram illustrating the principle of a flywheel energy storage method for participating in primary frequency regulation coordination control of the power grid, as provided by the present invention. Figure 1 and Figure 3As shown, the present invention provides a method for coordinating flywheel energy storage to participate in primary frequency regulation control of the power grid, comprising:

[0051] S101, Establish a model for flywheel energy storage to assist thermal power units with equal frequency regulation capacity to participate in the primary frequency regulation of the power grid; the model for flywheel energy storage to assist thermal power units with equal frequency regulation capacity to participate in the primary frequency regulation of the power grid is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the model to characterize the frequency regulation capacity of energy storage replacing thermal power units.

[0052] like Figure 2 As shown, the power generation coefficient of the energy storage equivalent thermal power unit is... K As a variable characterizing the frequency regulation capacity of energy storage replacing thermal power units.

[0053] ;

[0054] S102, obtain the power grid frequency value and the thermal power unit droop coefficient;

[0055] S103, determine the grid frequency deviation Δf, the frequency change rate d(Δf) / dt, and the primary frequency regulation command P based on the grid frequency value and the thermal power unit droop coefficient. G ;

[0056] S104. Based on the grid frequency change rate d(Δf) / dt and the flywheel SOC of the flywheel energy storage system, and using a fuzzy controller, determine the filtering time constant T.

[0057] The specific working process of the fuzzy controller is as follows:

[0058] Input and output quantities are fuzzified. The universe of discourse for the rate of change of frequency is set to [-2×10]. -3 2×10 -3 The fuzzy subset is {NB, NS, NE, PE, PS, PB}; the universe of discourse of the flywheel SOC is set to [0, 1], and the fuzzy subset is {NB, NS, ZE, PS, PB}; the universe of discourse of the filter time constant T is set to [0, 10], and the fuzzy subset is {NV, NB, NS, NE, PE, PS, PB, PV}.

[0059] Determine the membership functions. The frequency change rate uses a triangular membership function, while the flywheel SOC and filter time constant use triangular and trapezoidal membership functions, respectively. The input and output membership functions are as follows: Figure 4 Show.

[0060] Fuzzy reasoning. From the perspective of frequency change, when |d(Δf) / dt| increases, it indicates an increase in frequency regulation demand fluctuations. In this case, the filter time constant should be increased to smooth the output of the thermal power unit. When |d(Δf) / dt| is small, the filter time constant should be appropriately decreased to reduce flywheel output and save resources. From the perspective of flywheel state of charge, when the flywheel's state of charge is high, if d(Δf) / dt is greater than 0 and its absolute value is large, although the frequency regulation command has a rapid decreasing trend and requires a large amount of charging of the flywheel, the filter time constant should be decreased to avoid overcharging. If d(Δf) / dt is less than 0 and its absolute value is large, the flywheel needs a large amount of discharging, so the filter time constant should be increased. The opposite is true when the flywheel's state of charge is low. The fuzzy control rules designed according to the above principles are shown in Table 1:

[0061] Table 1 Fuzzy Control Rules

[0062]

[0063] Defuzzification. This invention uses the centroid method to take the centroid of the area enclosed by the membership function curve and the horizontal axis as the final output value of fuzzy inference.

[0064] S105, determine the low-frequency component and high-frequency component based on the filter time constant, the primary frequency regulation command, and the low-pass filter; the low-frequency component serves as the primary frequency regulation reference command for the thermal power unit; the high-frequency component serves as an input quantity for the flywheel energy storage system;

[0065] like Figure 5 As shown, the primary frequency regulation command P of the thermal power plant G The low-frequency component P obtained after passing through a low-pass filter with a variable time constant L As the primary frequency regulation reference command for thermal power units, the high-frequency component P H As an input to the flywheel energy storage system.

[0066] S106, based on the high-frequency components, the virtual droop power signal, and the first controller 1 and the second controller 2 that limit the flywheel output power using the Logistic regression function with the flywheel SOC as the independent variable, determine the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit.

[0067] Flywheel energy storage system such as Figure 6 As shown, the effective cooperation of the first controller 1 and the second controller 2 enables the system to prioritize the response to the high-frequency component of the thermal power frequency regulation command. When the high-frequency component exceeds the flywheel output margin, the flywheel cannot provide additional active power due to its output power limitation. At this time, the first controller 1 limits the high-frequency component, and the thermal power unit compensates for the power output that the flywheel cannot handle.

[0068] S106 specifically includes:

[0069] The first controller uses a Logistic regression function with flywheel SOC as the independent variable to limit high-frequency components, and determines the supplementary power of the thermal power unit based on the output of the first controller and the high-frequency components.

[0070] The second controller uses the output of the first controller and the virtual droop power signal to determine the theoretical expected power of the flywheel and the flywheel SOC to determine the actual output power of the flywheel energy storage system.

[0071] The output of the first controller specifically includes the following formula:

[0072] ;

[0073] Among them, P af1 P is the output of the first controller. d P is the discharge power. c For charging power, P rf1 The input is determined based on the high-frequency components.

[0074] Using formula Determine the supplementary power of thermal power units;

[0075] Among them, P b To supplement the power of thermal power units, P H For high-frequency components, P af1 This is the output of the first controller.

[0076] S107, determine the actual frequency regulation command of the thermal power unit based on the supplementary power of the thermal power unit and the low-frequency component;

[0077] S107 specifically includes:

[0078] Using formula Determine the actual frequency regulation command for the thermal power unit;

[0079] Among them, P G ’ P is the actual frequency regulation command for thermal power units. L It is a low-frequency component.

[0080] S108, frequency regulation is performed based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity participating in the primary frequency regulation model of the power grid.

[0081] Based on the traditional primary frequency regulation model of thermal power units, this invention establishes a model for thermal power units with equal frequency regulation capacity to participate in the primary frequency regulation of the power grid using flywheel energy storage. It also proposes a coordinated control strategy based on fuzzy control and a control strategy for the flywheel energy storage system that prioritizes response to high-frequency commands from thermal power plants, thereby improving the frequency stability of the power grid and the smoothness of the output of thermal power units.

[0082] By comparing the frequency regulation of thermal power units with the same frequency regulation capacity, the thermal-storage synergistic strategy proposed in this patent has the following advantages:

[0083] Compared to frequency regulation of thermal power units, the maximum frequency deviation of the system decreased by 35.92% and the steady-state frequency deviation decreased by 12.67% under the coordinated control strategy, which greatly improved the frequency regulation quality.

[0084] Compared to frequency regulation of thermal power units, the coordinated control strategy increased the unit's ramp-up rate by 74%, and reduced the system output lag time, rise time, and settling time by 42%, 43%, and 28%, respectively, significantly improving the unit's ramp-up rate and accelerating the system's response speed.

[0085] Under the coordinated control strategy, the short-term power contribution of the flywheel energy storage system is 7.8 times that of the thermal power with equal frequency regulation capacity, and the long-term power contribution is 3 times that of the thermal power. The more power the flywheel contributes in the short term, the smoother the output of the thermal power unit, and the better it can give full play to the short-term output characteristics of the flywheel and the long-term output characteristics of the thermal power.

[0086] Under continuous disturbance conditions, the maximum frequency deviation of the system under the control strategy proposed in this paper is reduced by 28%, the peak value of the output power change of the thermal power unit is reduced by 35.8%, and the number of fluctuations is reduced by 46.4%, which effectively reduces the output fluctuation of the thermal power unit, ensures the safe operation of the thermal power unit, and improves the service life of the unit.

[0087] As another specific embodiment, the present invention also provides a flywheel energy storage participating in grid primary frequency regulation coordination control system, comprising:

[0088] The model building module is used to build a model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid; the model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the model to characterize the frequency regulation capacity of energy storage replacing thermal power units.

[0089] The parameter acquisition module is used to acquire the power grid frequency value and the thermal power unit droop coefficient;

[0090] The parameter calculation module is used to determine the grid frequency deviation, frequency change rate, and primary frequency regulation command based on the grid frequency value and the thermal power unit droop coefficient.

[0091] The filter time constant determination module is used to determine the filter time constant based on the grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and by using a fuzzy controller.

[0092] The low-frequency component and high-frequency component determination module is used to determine the low-frequency component and high-frequency component based on the filter time constant, the primary frequency modulation command, and the low-pass filter; the low-frequency component serves as the primary frequency modulation reference command for the thermal power unit; and the high-frequency component serves as an input quantity for the flywheel energy storage system.

[0093] The module for determining the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit is used to determine the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit based on the high-frequency component, the virtual droop power signal, and the first and second controllers that limit the flywheel output power using a Logistic regression function with the flywheel SOC as the independent variable.

[0094] The actual frequency regulation command determination module for thermal power units is used to determine the actual frequency regulation command for thermal power units based on the supplementary power and low-frequency components of the thermal power units.

[0095] The frequency regulation module is used to regulate the frequency of the thermal power unit based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with the same frequency regulation capacity participating in the primary frequency regulation model of the power grid.

[0096] In order to execute the method corresponding to Embodiment 1 above and achieve the corresponding functions and technical effects, the present invention provides a flywheel energy storage participating in the primary frequency regulation coordination control system of the power grid, including: at least one processor, at least one memory, and computer program instructions stored in the memory, wherein the method is implemented when the computer program instructions are executed by the processor.

[0097] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0098] This document uses specific examples to illustrate the principles and implementation methods of the present invention. The descriptions of the above embodiments are only for the purpose of helping to understand the method and core ideas of the present invention. Furthermore, those skilled in the art will recognize that, based on the ideas of the present invention, there will be changes in the specific implementation methods and application scope. Therefore, the content of this specification should not be construed as a limitation of the present invention.

Claims

1. A method for coordinating flywheel energy storage to participate in primary frequency regulation control of a power grid, characterized in that, include: A flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity is established to participate in the primary frequency regulation of the power grid. The flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the thermal power unit to characterize the frequency regulation capacity of the thermal power unit replaced by energy storage. Obtain the power grid frequency value and the thermal power unit droop coefficient; The grid frequency deviation, frequency change rate, and primary frequency regulation command are determined based on the grid frequency value and the thermal power unit droop coefficient. Based on the grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and using a fuzzy controller, the filtering time constant is determined. The low-frequency and high-frequency components are determined based on the filter time constant, the primary frequency modulation command, and the low-pass filter. The low-frequency component serves as a primary frequency regulation reference command for the thermal power unit; the high-frequency component serves as an input to the flywheel energy storage system. Based on the high-frequency components, the virtual droop power signal, and the first and second controllers that limit the flywheel output using a Logistic regression function with flywheel SOC as the independent variable, the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit are determined. The actual frequency regulation command of the thermal power unit is determined based on the supplementary power and low-frequency components of the thermal power unit. Frequency regulation is carried out based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with equal frequency regulation capacity participating in the primary frequency regulation model of the power grid. The first and second controllers, which limit the flywheel output based on high-frequency components, virtual droop power signals, and a Logistic regression function with flywheel SOC as the independent variable, determine the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit. Specifically, this includes: The first controller uses a Logistic regression function with flywheel SOC as the independent variable to limit high-frequency components, and determines the supplementary power of the thermal power unit based on the output of the first controller and the high-frequency components. The second controller uses the output of the first controller and the virtual droop power signal to determine the theoretical expected power of the flywheel and the flywheel SOC to determine the actual output power of the flywheel energy storage system. The output of the first controller specifically includes the following formula: ； Among them, P af1 P is the output of the first controller. d P is the discharge power. c For charging power, P rf1 The input is determined based on the high-frequency components; When the high-frequency component exceeds the flywheel output margin, the first controller uses a logistic regression function with the flywheel SOC as the independent variable to limit the high-frequency component, and determines the supplementary power of the thermal power unit based on the output of the first controller and the high-frequency component, specifically including: Using formula Determine the supplementary power of thermal power units; Among them, P b To supplement the power of thermal power units, P H For high-frequency components, P af1 This is the output of the first controller; The process of determining the actual frequency regulation command of the thermal power unit based on the supplementary power and low-frequency components specifically includes: Using formula Determine the actual frequency regulation command for the thermal power unit; Among them, P G ’ P is the actual frequency regulation command for thermal power units. L It is a low-frequency component.

2. A flywheel energy storage system for coordinating primary frequency regulation in a power grid, used to implement the flywheel energy storage system for coordinating primary frequency regulation in a power grid as described in claim 1, characterized in that, include: The model building module is used to establish a model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid; the model of flywheel energy storage assisting thermal power units with equal frequency regulation capacity participating in the primary frequency regulation of the power grid is used to quantitatively analyze the dynamic complementary coupling relationship between energy storage and thermal power, and variables are set in the thermal power units to characterize the frequency regulation capacity of energy storage replacing thermal power units. The parameter acquisition module is used to acquire the power grid frequency value and the thermal power unit droop coefficient; The parameter calculation module is used to determine the grid frequency deviation, frequency change rate, and primary frequency regulation command based on the grid frequency value and the thermal power unit droop coefficient. The filter time constant determination module is used to determine the filter time constant based on the grid frequency change rate and the flywheel SOC of the flywheel energy storage system, and by using a fuzzy controller. The low-frequency component and high-frequency component determination module is used to determine the low-frequency component and high-frequency component based on the filter time constant, the primary frequency modulation command, and the low-pass filter; the low-frequency component serves as the primary frequency modulation reference command for the thermal power unit; and the high-frequency component serves as an input quantity for the flywheel energy storage system. The module for determining the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit is used to determine the actual output power of the flywheel energy storage system and the supplementary power of the thermal power unit based on the high-frequency component, the virtual droop power signal, and the first and second controllers that limit the flywheel output power using a Logistic regression function with the flywheel SOC as the independent variable. The actual frequency regulation command determination module for thermal power units is used to determine the actual frequency regulation command for thermal power units based on the supplementary power and low-frequency components of the thermal power units. The frequency regulation module is used to regulate the frequency of the thermal power unit based on the actual frequency regulation command of the thermal power unit, the actual output power of the flywheel energy storage system, and the flywheel energy storage auxiliary thermal power unit with the same frequency regulation capacity participating in the primary frequency regulation model of the power grid.

3. A flywheel energy storage system participating in primary frequency regulation coordination control of the power grid, characterized in that, include: The system comprises at least one processor, at least one memory, and computer program instructions stored in the memory, which, when executed by the processor, implement a flywheel energy storage participation in primary frequency regulation coordination control of the power grid as described in claim 1.

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