Network construction type wind storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization

Abstract

The invention provides a network construction type wind storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization, and the method comprises the steps: controlling a wind turbine to operate in a load shedding power standby frequency modulation PRFC mode during wind storage combined frequency modulation; the actual system angular frequency and disturbance quantity of the fan unit are obtained, and the output power of a wind turbine is obtained according to the actual system angular frequency and disturbance quantity; according to the actual system angular frequency and the net construction fan rated angular frequency, the system angular frequency variable quantity is obtained; according to the system angular frequency variable quantity and a frequency modulation coefficient, the frequency modulation output power variable quantity of the wind turbine is obtained, and the frequency modulation coefficient is used for dynamically adjusting the frequency modulation capacity of the net construction draught fan; and obtaining output reference power according to the wind turbine output power and the wind turbine frequency modulation output power variation, and performing frequency modulation according to the output reference power. And the wind turbine can dynamically adjust the system stability according to the dynamic characteristics of the wind turbine in the frequency modulation process.

Description

Technical Field

[0001] The present application relates to the field of wind power generation control technology, and in particular to a grid-type wind-storage frequency regulation control method based on optimization of rotor kinetic energy and energy storage SOC. Background Art

[0002] Grid-connected wind turbines are a new type of wind power technology. Compared with traditional grid-following wind turbines, they can actively sense grid disturbances, have controllable damping capabilities, and can provide active frequency and voltage support for high-proportion wind power grid systems.

[0003] Grid-connected wind power systems primarily employ two control strategies: rotor kinetic frequency regulation and load-shedding power reserve frequency regulation (PRFC). The former relies on adjusting wind turbine speed to release or absorb kinetic energy for rapid frequency response; the latter operates off the maximum power point to reserve some power, which serves as a frequency margin during frequency fluctuations. However, relying solely on the frequency response of the wind turbine itself still has limitations in terms of power regulation speed and stability, making it difficult to achieve efficient support under large disturbances and highly variable grid conditions.

[0004] Therefore, wind-storage combined frequency regulation control has become a key approach to improving the frequency regulation capabilities of grid-connected wind power systems. However, existing wind-storage combined frequency regulation control techniques fail to fully consider the impact of changes in wind power system operating conditions and energy storage status on frequency regulation, thus affecting the stability of wind-storage combined frequency regulation. Summary of the Invention

[0005] The present application provides a grid-type wind storage frequency regulation control method based on rotor kinetic energy and energy storage SOC optimization to solve the technical problems mentioned in the background technology.

[0006] In a first aspect, the present application provides a grid-type wind-storage frequency regulation control method based on rotor kinetic energy and energy storage SOC optimization, comprising: When the grid frequency difference is greater than or equal to the frequency difference in the frequency regulation dead zone, the grid-connected wind turbine is controlled to perform wind-storage combined frequency regulation. When the wind-storage combined frequency regulation is performed, the wind turbine is controlled to operate in the load-shedding power standby frequency regulation PRFC mode. Obtaining an actual system angular frequency and a disturbance value of the wind turbine group, and obtaining a wind turbine output power according to the actual system angular frequency and the disturbance value; Obtaining a system angular frequency change according to the actual system angular frequency and the rated angular frequency of the grid-forming wind turbine; Obtaining a wind turbine frequency modulation output power change according to the system angular frequency change and the frequency modulation coefficient, wherein the frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the grid-forming wind turbine; An output reference power is obtained according to the wind turbine output power and the change in the wind turbine frequency modulation output power, so as to perform frequency modulation according to the output reference power.

[0007] Optionally, before obtaining the wind turbine frequency modulation output power change according to the system angular frequency change and the frequency modulation coefficient, the method further includes: Obtain the maximum speed change, minimum speed change, rotor speed deviation of the network wind turbine during the current frequency modulation process, as well as the minimum and maximum limit frequency modulation power; Obtaining a proportion of the wind turbine's current adjustable kinetic energy relative to its maximum adjustable kinetic energy based on the maximum speed change, the minimum speed change, the rotor speed deviation of the grid-connected wind turbine during the current frequency modulation process, and the grid frequency difference; Obtaining a ratio of the wind turbine's current variable output power to its maximum variable output power according to the minimum limit frequency modulation power, the maximum limit frequency modulation power, and the grid frequency difference; The frequency modulation coefficient is obtained according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0008] Optionally, obtaining the frequency modulation coefficient according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power includes: Determining the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power; The frequency modulation coefficient is obtained based on a Sigmoid function according to the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0009] Optionally, obtaining the wind turbine output power according to the actual system angular frequency and the disturbance amount includes: Obtaining an initial wind turbine output power according to the actual system angular frequency and the disturbance amount; The wind turbine output power is obtained according to the initial wind turbine output power and the limit frequency modulation power.

[0010] Optionally, also include: Obtain the current charge and discharge power of the energy storage system corresponding to the grid-forming wind turbine, the currently available charge and discharge capacity of the energy storage, the energy storage system power, and the initial value of the energy storage SOC; Obtaining a current energy storage SOC value corresponding to the current moment according to the currently available charge and discharge capacity of the energy storage and the power of the energy storage system; Obtaining a predicted energy storage SOC value corresponding to the next moment according to the charge and discharge power corresponding to the current moment, the current energy storage SOC value, and the initial energy storage SOC value; Obtaining the energy storage output compensation power corresponding to the current moment according to the energy storage SOC prediction value and the currently available charge and discharge capacity of the energy storage; Based on the characteristics of the inverse tangent function, according to the current value of the energy storage SOC, a compensation coefficient corresponding to the current moment is obtained; Obtaining a target energy storage output compensation power corresponding to the current moment according to the energy storage output compensation power, the compensation coefficient corresponding to the current moment, and the maximum available capacity of the energy storage; The charge and discharge power at the current moment is corrected according to the target energy storage output compensation power corresponding to the current moment to obtain the corrected charge and discharge power.

[0011] Optionally, obtaining the charge and discharge power corresponding to the current moment includes: Obtaining a droop coefficient corresponding to the current moment according to the current energy storage SOC value, the initial energy storage SOC value, and the grid frequency difference; Obtaining a storage energy output reference power corresponding to the current moment according to the droop coefficient corresponding to the current moment and the grid frequency difference; The charge and discharge power corresponding to the current moment is obtained according to the energy storage output reference power corresponding to the current moment.

[0012] In a second aspect, the present application provides a grid-type wind-storage frequency regulation control device based on optimization of rotor kinetic energy and energy storage SOC, comprising: A mode switching module is used to control the grid-connected wind turbine to perform wind-storage combined frequency modulation when the grid frequency difference is greater than or equal to the frequency modulation dead zone frequency difference, and to control the wind turbine to operate in the load-shedding power standby frequency modulation PRFC mode during wind-storage combined frequency modulation; an acquisition module, configured to acquire an actual system angular frequency and a disturbance value of the wind turbine group, and obtain an output power of the wind turbine according to the actual system angular frequency and the disturbance value; a rotor primary frequency modulation module, configured to obtain a system angular frequency change based on the actual system angular frequency and the rated angular frequency of the grid-forming wind turbine; and to obtain a wind turbine frequency modulation output power change based on the system angular frequency change and a frequency modulation coefficient, wherein the frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the grid-forming wind turbine; The frequency modulation output module is used to obtain an output reference power according to the wind turbine output power and the change in the wind turbine frequency modulation output power, so as to perform frequency modulation according to the output reference power.

[0013] Optionally, the acquisition module obtains the wind turbine output power according to the actual system angular frequency and the disturbance amount, specifically for: Obtaining an initial wind turbine output power according to the actual system angular frequency and the disturbance amount; The wind turbine output power is obtained according to the initial wind turbine output power and the limit frequency modulation power.

[0014] Optionally, before obtaining the wind turbine frequency modulation output power variation according to the system angular frequency variation and the frequency modulation coefficient, the rotor primary frequency modulation module is further configured to: Obtain the maximum speed change, minimum speed change, rotor speed deviation of the network wind turbine during the current frequency modulation process, as well as the minimum and maximum limit frequency modulation power; Obtaining a proportion of the wind turbine's current adjustable kinetic energy relative to its maximum adjustable kinetic energy based on the maximum speed change, the minimum speed change, the rotor speed deviation of the grid-connected wind turbine during the current frequency modulation process, and the grid frequency difference; Obtaining a ratio of the wind turbine's current variable output power to its maximum variable output power according to the minimum limit frequency modulation power, the maximum limit frequency modulation power, and the grid frequency difference; The frequency modulation coefficient is obtained according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0015] Optionally, the rotor primary frequency modulation module obtains the frequency modulation coefficient according to a ratio of the current adjustable kinetic energy of the fan to its maximum adjustable kinetic energy and a ratio of the current variable output power of the fan to its maximum variable output power, specifically for: Determining the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power; The frequency modulation coefficient is obtained based on a Sigmoid function according to the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0016] Optional energy storage frequency modulation module for: Obtain the current charge and discharge power of the energy storage system corresponding to the grid-forming wind turbine, the currently available charge and discharge capacity of the energy storage, the energy storage system power, and the initial value of the energy storage SOC; Obtaining a current energy storage SOC value corresponding to the current moment according to the currently available charge and discharge capacity of the energy storage and the power of the energy storage system; Obtaining a predicted energy storage SOC value corresponding to the next moment according to the charge and discharge power corresponding to the current moment, the current energy storage SOC value, and the initial energy storage SOC value; Obtaining the energy storage output compensation power corresponding to the current moment according to the energy storage SOC prediction value and the currently available charge and discharge capacity of the energy storage; Based on the characteristics of the inverse tangent function, according to the current value of the energy storage SOC, a compensation coefficient corresponding to the current moment is obtained; Obtaining a target energy storage output compensation power corresponding to the current moment according to the energy storage output compensation power, the compensation coefficient corresponding to the current moment, and the maximum available capacity of the energy storage; The charge and discharge power at the current moment is corrected according to the target energy storage output compensation power corresponding to the current moment to obtain the corrected charge and discharge power.

[0017] Optionally, the energy storage frequency modulation module obtains the charge and discharge power corresponding to the current moment, specifically for: Obtaining a droop coefficient corresponding to the current moment according to the current energy storage SOC value, the initial energy storage SOC value, and the grid frequency difference; Obtaining a storage energy output reference power corresponding to the current moment according to the droop coefficient corresponding to the current moment and the grid frequency difference; The charge and discharge power corresponding to the current moment is obtained according to the energy storage output reference power corresponding to the current moment.

[0018] In a third aspect, the present application provides an electronic device, comprising: a processor and a memory; Memory stores computer-executable instructions; The processor executes the computer-executable instructions stored in the memory, so that the processor performs the method as described in any one of the first aspects.

[0019] In a fourth aspect, an embodiment of the present application provides a readable storage medium, including a program or instruction. When the program or instruction runs on a computer, the method described in any one of the above-mentioned first aspects is executed.

[0020] In a fifth aspect, an embodiment of the present application provides a computer program product, comprising a computer program, which, when executed by a processor, implements the method as described in any one of the first aspects.

[0021] The grid-type wind-storage frequency regulation control method based on rotor kinetic energy and energy storage SOC optimization provided in this application obtains the grid frequency difference and determines whether the grid frequency difference is greater than or equal to the frequency difference in the frequency regulation dead zone; when the grid frequency difference is greater than or equal to the frequency difference in the frequency regulation dead zone, controls the wind turbine unit to operate in the load-reduced power standby frequency regulation PRFC mode; obtains the actual system angular frequency and disturbance of the wind turbine unit, and obtains the wind turbine output power based on the actual system angular frequency and disturbance; obtains the speed difference based on the actual system angular frequency and the rated speed of the wind turbine unit; obtains the additional electromagnetic power increment based on the speed difference and the frequency regulation coefficient, and the frequency regulation coefficient is used to adjust the frequency regulation capability of the wind turbine unit; obtains the output reference power based on the wind turbine output power and the electromagnetic power increment, and performs frequency regulation based on the output reference power. In this embodiment, when the grid-type wind-storage combined frequency regulation control is used, the frequency regulation coefficient is introduced during the rotor kinetic energy frequency regulation, thereby achieving the purpose of adjusting the wind turbine frequency regulation capability through the frequency regulation coefficient, thereby minimizing the secondary frequency fluctuation when the speed recovers. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, a brief introduction will be given below to the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0023] Figure 1 A flow chart of a grid-type wind-storage frequency regulation control method based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application; Figure 2 A schematic diagram of the structure of a fan unit speed regulation control block diagram provided in one embodiment of the present application; Figure 3 A diagram showing the relationship between virtual inertia, frequency deviation, and voltage fluctuation provided in one embodiment of the present application; Figure 4 A flow chart of a frequency modulation control method for energy storage SOC charge and discharge limits and recovery provided in one embodiment of the present application; Figure 5 A block diagram of a frequency modulation control method for energy storage SOC charge and discharge limits and recovery provided in one embodiment of the present application; Figure 6 Provided for an embodiment of this application k add Root loci when changing; Figure 7 A simulation diagram of a grid-type wind-storage frequency modulation control method based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application; Figure 8A comparison chart of the frequency responses of a grid-type wind-storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization provided in one embodiment of the present application and an existing method; Figure 9 A comparison chart of wind power output power between a grid-connected wind-storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization provided in one embodiment of the present application and an existing method; Figure 10 A comparison chart of the energy storage output power of a grid-type wind-storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization provided in one embodiment of the present application and an existing method; Figure 11 A comparison chart of wind turbine speeds between a grid-type wind-storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization provided in one embodiment of the present application and an existing method; Figure 12 A comparison chart of the energy storage SOC of a grid-type wind-storage frequency modulation control method based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application and an existing method; Figure 13 A schematic structural diagram of a grid-type wind-storage frequency regulation control device based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application; Figure 14 A schematic diagram of the structure of an electronic device provided in one embodiment of the present application. DETAILED DESCRIPTION

[0024] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application are clearly and completely described below. Obviously, the described embodiments are part of the embodiments of this application, not all of them. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts also fall within the scope of protection of this application.

[0025] For the grid-type wind-storage combined frequency regulation, the transfer function corresponding to the system frequency regulation is: (1) Among them, Δ P W is the wind power increment, Δ P E is the power increment of the energy storage system, Δ P L is the load change, Δ P G is the active power increment of other energy units outside the wind storage system participating in the primary frequency regulation, H and D are the system inertia constant and damping constant respectively, Δ f is the grid frequency difference, Δ P is the power change, prepresents the system order, s 1 represents the Laplace operator.

[0026] Among them, the output power change Δ P W The expression is as follows: (2) Among them, Δ P * ref =Δ P del +Δ P add , that is, the active power reference value controlled by VSG is determined by the wind turbine output power P del and FM output power P add composition, K vsg is the primary frequency modulation coefficient, D vsg is the virtual damping of VSG, J vsg is the virtual inertia of VSG, and Δω is the change of system angular frequency.

[0027] Among them, the power increment of the energy storage system Δ P E The expression is as follows: (3) in, J bess is the equivalent moment of inertia of the supercapacitor, w N is the rated angular frequency of the grid fan, represents the rate of change of frequency, D f Indicates the primary frequency modulation damping coefficient of the supercapacitor (simulated power-frequency response).

[0028] Next, the technical solution of this embodiment is described based on the grid-type wind-storage combined frequency regulation control.

[0029] Figure 1 This is a flow chart of a grid-type wind-storage frequency regulation control method based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application. Figure 1 As shown, the grid-type wind-storage combined frequency regulation control method provided in this embodiment includes: S101. Obtain the grid frequency difference, and when the grid frequency difference is greater than or equal to the frequency difference in the frequency regulation dead zone, control the grid-connected wind turbines to perform wind-storage combined frequency regulation. When performing wind-storage combined frequency regulation, control the wind turbine units to operate in a load-reduced power standby frequency regulation PRFC mode.

[0030] In this step, when the grid frequency difference is within the frequency dead zone, frequency modulation is not required. This can avoid frequent parameter adjustments of the wind turbine unit and reduce frequent movements of mechanical components due to small frequency differences, thereby extending equipment life and improving grid stability.

[0031] When a change in the grid frequency is detected, the grid frequency difference Δ is obtained f , in Δ f When the frequency difference is greater than or equal to the frequency regulation dead zone, wind-storage joint frequency regulation is performed; otherwise, no frequency regulation is performed.

[0032] Among them, for the wind-storage combined frequency regulation, the frequency regulation of the wind turbine itself is as follows: Figure 2 As shown, if the fan unit is running in MPPT mode at this time, the fan unit is first controlled to switch to run in PRFC mode. Figure 2 The d% in the formula is the load reduction rate of the grid fan.

[0033] S102: Acquire the actual system angular frequency and disturbance of the wind turbine group, and obtain the wind turbine output power according to the actual system angular frequency and disturbance.

[0034] In this step, when the wind turbine unit is operating in PRFC mode, the actual system angular frequency ω and disturbance of the wind turbine unit are obtained, so as to obtain the wind turbine output power according to the actual system angular frequency and disturbance. P del .

[0035] Optionally, a specific implementation of S102 is: S1021. Obtain the initial wind turbine output power according to the actual system angular frequency and disturbance amount.

[0036] S1022: Obtain wind turbine output power according to the initial wind turbine output power and the limit frequency modulation power.

[0037] Specifically, the wind turbine output power cannot exceed the limit frequency modulation power. Therefore, the initial wind turbine output power is compared with the limit frequency modulation power. When the initial wind turbine output power is less than the limit frequency modulation power, the initial wind turbine output power is determined as the wind turbine output power; when the initial wind turbine output power is greater than or equal to the limit frequency modulation power, the limit frequency modulation power is determined as the wind turbine output power.

[0038] S103: Obtain a system angular frequency variation according to the actual system angular frequency and the rated angular frequency of the grid-connected wind turbines.

[0039] In this step, according to the actual system angular frequency ω and the rated angular frequency ω of the network fan N , and obtain the system angular frequency change Δω.

[0040] S104. Obtain a change in the frequency modulation output power of the wind turbine according to the change in the system angular frequency and the frequency modulation coefficient. The frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the network wind turbines.

[0041] In this step, the frequency modulation coefficient k rp The rotor kinetic energy control is introduced to evaluate the primary frequency regulation capability of the grid-type wind turbine in PRFC mode. k rp It is related to the speed and the grid frequency difference, so the frequency modulation coefficient k rp It changes dynamically.

[0042] Among them, the system angular frequency change Δω and the frequency modulation coefficient k rp , obtain the wind turbine frequency modulation output power change Δ P add .

[0043] S105 : Obtain an output reference power according to the wind turbine output power and the change in the wind turbine frequency modulation output power, so as to perform frequency modulation according to the output reference power.

[0044] In this step, according to the wind turbine output power P del and wind turbine frequency modulation output power change Δ P add Get the output reference power of the virtual synchronous generator VSG , which is shown in formula (4): (4) Wind turbine output reference power P*ref Perform frequency modulation.

[0045] In this embodiment, when the grid frequency difference is greater than or equal to the frequency difference in the frequency modulation dead zone, the grid-connected wind turbine is controlled to perform wind-storage combined frequency modulation. During the wind-storage combined frequency modulation, the wind turbine is controlled to operate in the load-reduced power standby frequency modulation PRFC mode; the actual system angular frequency and disturbance amount of the wind turbine unit are obtained, and the wind turbine output power is obtained based on the actual system angular frequency and disturbance amount; the system angular frequency change is obtained based on the actual system angular frequency and the rated angular frequency of the grid-connected wind turbine; the wind turbine frequency modulation output power change is obtained based on the system angular frequency change and the frequency modulation coefficient, and the frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the grid-connected wind turbine; the output reference power is obtained based on the wind turbine output power and the wind turbine frequency modulation output power change, so as to perform frequency modulation based on the output reference power. In this embodiment, a frequency modulation coefficient is introduced into the rotor kinetic energy frequency modulation during the grid-type wind-storage combined frequency modulation control. Since the frequency modulation coefficient is related to the rotational speed and the grid frequency difference, the frequency modulation parameters change dynamically. Thus, the frequency modulation coefficient enables the wind turbine to dynamically adjust the system stability according to its own dynamic characteristics during the frequency modulation process, thereby minimizing the secondary frequency fluctuation when the rotational speed recovers.

[0046] Optionally, before S104, the method further includes: S1041. Obtain the maximum speed change, the minimum speed change, the rotor speed deviation of the network wind turbine during the current frequency modulation process, and the minimum and maximum limit frequency modulation power.

[0047] In this step, the maximum speed change, the minimum speed change, the minimum limit frequency modulation power, and the maximum limit frequency modulation power can be obtained by referring to the existing technology. Among them, the rotor speed deviation of the network wind turbine currently participating in the frequency modulation process can be obtained by the following method: Among them, the additional electromagnetic power increment of the grid-type wind turbine based on VSG control during the frequency regulation control process is as follows; (5) The electromagnetic power correction value output by the additional frequency modulation control module of the grid-type wind turbine is: (6) in, H WTG is the fan inertia time constant, ω r0 is the initial value of the rotor speed, k del is the load reduction rate. According to formula (5) and formula (6), the rotor speed deviation expression of the fan during the current frequency modulation process is: (7) S1042. Obtain a proportion of the current adjustable kinetic energy of the wind turbine unit relative to its maximum adjustable kinetic energy based on the maximum speed change, the minimum speed change, the rotor speed deviation of the wind turbine currently participating in frequency modulation, and the grid frequency difference.

[0048] In this step, the proportion of the wind turbine unit's current adjustable kinetic energy relative to its maximum adjustable kinetic energy is obtained according to formula (8): k r : (8) Among them, Δ ω rmin , Δ ω rmax are the per-unit values of the maximum and minimum speed changes, Δ ω r It is the rotor speed deviation of the network fan during the current frequency regulation process.

[0049] S1043. Obtain a ratio of the wind turbine's current variable output power to its maximum variable output power based on the minimum limit frequency modulation power, the maximum limit frequency modulation power, and the grid frequency difference.

[0050] In this step, the ratio of the wind turbine’s current variable output power to its maximum variable output power is obtained according to formula (9): k p : (9) Among them, Δ P max , Δ P min They are the per-unit values of the minimum and maximum extreme FM powers respectively.

[0051] S1044. Obtain a frequency modulation coefficient according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0052] In this step, you can select the ratio of the fan unit's current adjustable kinetic energy to its maximum adjustable kinetic energy. k r The ratio of the wind turbine's current variable output power to its maximum variable output power k p Use any one of them to calculate the frequency modulation coefficient.

[0053] Specifically, S1044 includes the following steps: Step 1: Determine the smaller value of the ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and the ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0054] Specifically, according to k r and k p When the grid frequency decreases, k r Increases with the increase of wind speed, k p When the grid frequency increases, the two trends are opposite. Therefore, the frequency regulation capability of the grid-type wind turbine should depend on the smaller value of the two, that is, f =min[ kr , k p ].

[0055] Step 2: Obtain a frequency modulation coefficient based on a Sigmoid function according to the smaller value of the ratio of the wind turbine's current adjustable kinetic energy to its maximum adjustable kinetic energy and the ratio of the wind turbine's current variable output power to its maximum variable output power.

[0056] Specifically, according to f =min[ kr , k p ], determine the frequency modulation coefficient based on the Sigmoid function k rp , that is, according to formula (10) k rp : (10) in, k rp Should follow the grid frequency deviation Δ f Gradually from 0 to 1, in order to give full play to the fan frequency regulation capability. a Control the rate of change. Too small or too large is not conducive to system stability. Parameter b determines the initial degree of fan participation in frequency modulation. Too large or too small will limit the frequency modulation effect. It is necessary to comprehensively consider the impact of the two on the frequency modulation coefficient. k rp , select a=0.217, b=2.536.

[0057] In this embodiment, by setting the frequency modulation coefficient, the frequency modulation coefficient changes dynamically according to the grid frequency deviation, so that the rotor kinetic energy state can be adaptively adjusted for power, the kinetic energy release process is optimized, and the secondary frequency drop caused by the rapid decrease in speed is suppressed, thereby improving the sustainability of frequency modulation and the efficiency of wind energy utilization.

[0058] In addition, in the grid-type wind-storage joint frequency regulation control, based on the rotor kinetic energy optimization strategy to improve the system frequency support capability of the grid-type wind turbine, in response to the dual needs of the system's high dynamic frequency fluctuation response and sustainable operation of the energy storage SOC, this application introduces supercapacitors as fast power support units to construct a multi-time scale frequency regulation system with wind and storage synergy and complementarity. By establishing a variable coefficient feedback control strategy that considers the energy storage SOC charging and discharging limits and SOC recovery characteristics, dynamic adaptive adjustment of the energy storage power is achieved, thereby further optimizing the frequency regulation performance and improving the stability and reliability of the power grid.

[0059] The relationship between the energy storage power command and the actual output can be described by a first-order inertia link, and its transfer function model is: (11) in, T bess is the response time constant of energy storage, s is the integration constant.

[0060] In the constant current charge and discharge mode, the terminal voltage of the supercapacitor changes continuously, and its charge and discharge power can be expressed as the first-order differential form of the voltage Uc:

[0061] (12) Where, U c is the voltage, P cha and P dis are charging power and discharging power respectively.

[0062] Based on the swing equation of the traditional synchronous generator, the virtual inertia control of the supercapacitor is expressed as: (13) in, S N is the rated capacity of the synchronous generator, Δ P is the power change. P With Δ f It is a positive correlation.

[0063] The synchronous generator regulates active power through rotor kinetic energy, and the supercapacitor regulates active power through charging and discharging. The power equations of the two are similar. The supercapacitor can be regarded as an energy storage element with virtual inertia. The right part of formula (13) is equivalent to Δ P , combining formula (12) and formula (13) to obtain formula (14): (14) According to formula (14), the equivalent moment of inertia constant of the supercapacitor is Jbess It is determined by a variety of factors, including system frequency, capacitance value, and voltage across the capacitor. These factors interact with each other and significantly affect the energy storage and release characteristics of supercapacitors under different operating conditions.

[0064] Among them, Figure 3 As shown, the equivalent moment of inertia constant of the supercapacitor when the capacitance value is 10F is shown. J bess Three-dimensional curve of the equivalent moment of inertia of supercapacitor as frequency deviation and voltage deviation change J bess It can be set by adjusting the capacitance value.

[0065] Figure 4 This is a flow chart of a frequency modulation control method for energy storage SOC charge and discharge limits and recovery provided in one embodiment of the present application. Figure 5 This is a block diagram of a frequency modulation control method for energy storage SOC charge and discharge limit and recovery provided in one embodiment of the present application. Figure 4 As shown, the method includes: S401. Obtain the current charge and discharge power of the energy storage system corresponding to the grid-connected wind turbine, the currently available charge and discharge capacity of the energy storage, the energy storage system power, and the initial energy storage SOC value.

[0066] In this step, when implementing grid-connected wind and energy storage combined frequency regulation, the energy storage system participates in frequency regulation. The energy storage system's SOC charge / discharge limits and SOC recovery characteristics play a significant role in grid frequency regulation. Therefore, in this embodiment, a power feedback control link for the SOC charge / discharge limits is added to optimize power distribution, improve frequency regulation stability and sustainability, and enhance the safety of energy storage operations.

[0067] Therefore, the charging and discharging power of the energy storage system at the current moment is obtained , as well as the currently available charging and discharging capacity of the energy storage, the energy storage system power and the initial value of the energy storage SOC.

[0068] Among them, the charging and discharging power of the energy storage system at the current moment It can be obtained through the following methods: S4011. Obtain a droop coefficient corresponding to the current moment according to the current energy storage SOC value, the initial energy storage SOC value, and the grid frequency difference.

[0069] Specifically, according to formula (15), the droop coefficient corresponding to the current moment is obtained: : (15) in, ξ is the power exponential constant.

[0070] S4012. Obtain the energy storage output reference power corresponding to the current moment according to the droop coefficient and the grid frequency difference corresponding to the current moment.

[0071] Specifically, according to formula (16), the energy storage output reference power corresponding to the current moment is obtained: : (16) S4013. Obtain the charge and discharge power corresponding to the current moment according to the energy storage output reference power corresponding to the current moment.

[0072] Specifically, according to formula (11) and the energy storage output reference power corresponding to the current moment , obtain the charge and discharge power corresponding to the current moment : (17) Therefore, in this embodiment, the energy storage is dynamically regulated based on the SOC state, and the variable droop coefficient adjustment and charge and discharge limit feedback control are integrated to optimize the frequency modulation response. An SOC adaptive adjustment mechanism is constructed to dynamically adjust the energy storage droop coefficient with the SOC. When the SOC is high, the discharge frequency modulation capability is enhanced, and when the SOC is low, the discharge is suppressed to prevent over-discharge from affecting the life.

[0073] S402: Obtain the current energy storage SOC value corresponding to the current moment according to the currently available charge and discharge capacity of the energy storage and the energy storage system power.

[0074] In this step, the current energy storage SOC value corresponding to the current moment is obtained according to formula (18): (18) in, E bess is the currently available charge and discharge capacity of the energy storage, P bess is the power of the energy storage system, s is the integration constant, t Indicates the current time S403 : Obtain a predicted energy storage SOC value corresponding to the next moment according to the charge and discharge power, the current energy storage SOC value, and the initial energy storage SOC value corresponding to the current moment.

[0075] In this step, according to formula (19), the next moment ( t +1) The corresponding energy storage SOC prediction value: (19) S404: Obtain the energy storage output compensation power corresponding to the current moment according to the energy storage SOC prediction value and the currently available charge and discharge capacity of the energy storage.

[0076] In this step, after obtaining the energy storage SOC prediction value, it is multiplied by the currently available charge and discharge capacity of the energy storage and then integrated to obtain the energy storage output compensation power corresponding to the current moment.

[0077] S405 : Based on the characteristics of the inverse tangent function and the current value of the energy storage SOC, a compensation coefficient corresponding to the current moment is obtained.

[0078] In this step, considering the characteristic of the inverse tangent function approaching the extreme value, the inverse tangent function is used to construct the compensation coefficient corresponding to the spring energy storage SOC and the current moment k add The functional relationship between them is used to obtain the compensation coefficient corresponding to the current moment according to formula 20. k add : (20) in, α and β is the adjustment coefficient, α The value range is (0, 1.5); β The value range is (1, 3).

[0079] Among them, such as Figure 6 As shown in Figure 1, the frequency regulation control strategy considering the SOC charge and discharge limit and SOC recovery of the energy storage system dynamically adjusts the energy storage power to respond to system state changes, thereby optimizing the frequency regulation effect and improving the stability of the power grid. Based on the characteristics of the inverse tangent function, the battery SOC and k add The relationship between k add As the root locus approaches the imaginary axis, and a positive characteristic root appears in the real part, the system loses stability, such as Figure 6 As shown, therefore, by adjusting k add The value can avoid system instability and ensure stable operation of energy storage.

[0080] S406 , obtaining a target energy storage output compensation power corresponding to the current moment according to the energy storage output compensation power, the compensation coefficient corresponding to the current moment, and the maximum available capacity of the energy storage.

[0081] In this step, according to formula (21), the target energy storage output compensation power corresponding to the current moment is obtained: : (twenty one) in, SOC ( t +1)* E bess / s represents the energy storage output compensation power, in, Indicates the maximum capacity of energy storage available.

[0082] S407 , correcting the charge and discharge power at the current moment according to the target energy storage output compensation power corresponding to the current moment to obtain the corrected charge and discharge power.

[0083] In this step, if Figure 5 As shown, the target energy storage output compensation power corresponding to the current moment is Correct the current charge and discharge power obtained through S4011-S4013 to obtain the corrected charge and discharge power, thereby achieving dynamic power regulation of the energy storage SOC. Figure 5 Where d represents the number of hours of energy storage utilization, c represents the energy storage life, and Cn represents the energy storage capacitance constant.

[0084] In this embodiment, SOC feedback control is incorporated into the energy storage SOC recovery process to achieve dynamic, adaptive regulation of energy storage power. Furthermore, during wind-storage combined frequency regulation, the frequency support process of the wind-storage system at multiple time scales is coordinated based on rotor kinetic energy constraints and the dynamic regulation mechanism of the energy storage SOC. The proposed frequency response strategy fully considers the charge-discharge boundaries and dynamic recovery characteristics of the energy storage system, dynamically regulates the energy storage power based on the SOC state, and integrates variable droop coefficient regulation with charge-discharge limit feedback control to optimize the frequency regulation response. An adaptive regulation mechanism for energy storage SOC is constructed to dynamically adjust the energy storage droop coefficient with the energy storage SOC. This enhances discharge frequency regulation capabilities when the energy storage SOC is high and suppresses discharge when the energy storage SOC is low, preventing over-discharge from affecting its lifespan. Simultaneously, combining energy storage power constraints with energy storage SOC feedback control optimizes power distribution, improves frequency regulation stability, sustainability, and energy storage operational safety, and enables adaptive regulation of energy storage power in response to grid frequency deviations and load changes, significantly enhancing the system's rapid frequency response capabilities and operational adaptability.

[0085] Simulation example of the technical solution of this application: To verify the effectiveness of the proposed grid-connected wind-storage system joint frequency regulation control strategy based on rotor kinetic energy and energy storage SOC optimization, a simulation test system including grid-connected wind turbines, energy storage systems, synchronous generators and typical AC loads was built. Its structure is as follows: Figure 7 The wind farm consists of 15 doubly-fed induction wind turbines with a rated capacity of 5 MW, and the supporting energy storage system has a rated power of 3 MW and an energy storage capacity of 6 MWh.

[0086] To verify the effectiveness of the proposed strategy under variable wind speed conditions, a comparative analysis of the following three collaborative control strategies for grid-type wind-storage systems is conducted for step load disturbance conditions: ① improved droop control; ② traditional MPC control; ③ the grid-type wind-storage frequency regulation control based on rotor kinetic energy and energy storage SOC optimization mentioned in this application, denoted as EMPC control.

[0087] To verify the effectiveness of the proposed strategy under low wind speed of 7m / s, the initial SOC is set to 50%, and a step load disturbance with an amplitude of 30MW is added at 5s. In order to evaluate the control effect of the frequency regulation control strategy and the maintenance effect of the energy storage SOC, in addition to the maximum frequency deviation Δfmax and the steady-state frequency deviation Δ f s In addition to being an evaluation indicator, the absolute value of the SOC change rate is added to measure the effectiveness of the control strategy.

[0088] Absolute value of SOC change rate | vSOC The expression for | is: (twenty two) Where, t o 、 t s are the simulation start and end time, SOC o 、 SOC s are the charge states at the initial and end moments of energy storage frequency modulation, respectively.

[0089] Depend on Figures 8-12 It can be seen that the proposed EMPC control can dynamically adjust the wind-storage output ratio as the system frequency changes, give full play to the advantages of wind-storage coordinated frequency regulation, and improve system stability and economy. Combined with the frequency regulation indicators in Table 1, it can be seen that its maximum frequency deviation Δ f max Compared with droop control and traditional MPC control, the steady-state frequency deviation Δ f s It also reaches the minimum, which is 7.04% lower than the traditional MPC control.

[0090] Table 1 Frequency regulation index results at low wind speed

[0091] Under low wind speed conditions, the kinetic energy of the grid-connected wind turbines is insufficient, and the continuous frequency modulation of the wind turbines at the lowest speed is likely to cause machine shutdown and system instability. The grid-connected DFIG based on EMPC control prolongs the duration of the speed being maintained at the lowest point (0.733pu), which is 0.012pu higher than the other two methods, and the speed change is more stable; at the same time, the final v SOC The maximum output depth is 0.81, and the maximum output depth is reduced by about 22.64%. Therefore, by effectively ensuring the stable operation of the grid-connected wind turbines and improving energy utilization efficiency, the reliability and sustainability of the wind-storage system during the frequency regulation process can be enhanced.

[0092] Figure 13 This is a schematic diagram of the structure of a grid-type wind-storage frequency regulation control device based on optimization of rotor kinetic energy and energy storage SOC provided in one embodiment of the present application. Figure 13 As shown, the grid-type wind-storage combined frequency regulation control device includes: a mode switching module 901, an acquisition module 902, a primary frequency regulation module 903 and a frequency regulation output module 904. Optionally, as Figure 13 As shown, the grid-type wind-storage combined frequency regulation control device also includes: an energy storage frequency regulation module 905.

[0093] The mode switching module 901 is configured to control the grid-connected wind turbine to perform wind-storage combined frequency modulation when the grid frequency difference is greater than or equal to the frequency modulation dead zone frequency difference, and to control the wind turbine to operate in the load-shedding power standby frequency modulation PRFC mode during wind-storage combined frequency modulation. An acquisition module 902 is configured to acquire an actual system angular frequency and a disturbance value of the wind turbine group, and obtain a wind turbine output power based on the actual system angular frequency and the disturbance value; The rotor primary frequency modulation module 903 is configured to obtain a system angular frequency change based on the actual system angular frequency and the rated angular frequency of the grid-connected wind turbine; and to obtain a wind turbine frequency modulation output power change based on the system angular frequency change and a frequency modulation coefficient, wherein the frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the grid-connected wind turbine. The frequency modulation output module 904 is configured to obtain an output reference power according to the wind turbine output power and the change in the wind turbine frequency modulation output power, so as to perform frequency modulation according to the output reference power.

[0094] Optionally, the acquisition module 902 obtains the wind turbine output power according to the actual system angular frequency and the disturbance amount, specifically for: Obtaining an initial wind turbine output power according to the actual system angular frequency and the disturbance amount; The wind turbine output power is obtained according to the initial wind turbine output power and the limit frequency modulation power.

[0095] Optionally, before obtaining the wind turbine frequency modulation output power variation according to the system angular frequency variation and the frequency modulation coefficient, the rotor primary frequency modulation module 903 is further configured to: Obtain the maximum speed change, minimum speed change, rotor speed deviation of the network wind turbine during the current frequency modulation process, as well as the minimum and maximum limit frequency modulation power; Obtaining a proportion of the wind turbine's current adjustable kinetic energy relative to its maximum adjustable kinetic energy based on the maximum speed change, the minimum speed change, the rotor speed deviation of the grid-connected wind turbine during the current frequency modulation process, and the grid frequency difference; Obtaining a ratio of the wind turbine's current variable output power to its maximum variable output power according to the minimum limit frequency modulation power, the maximum limit frequency modulation power, and the grid frequency difference; The frequency modulation coefficient is obtained according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0096] Optionally, the rotor primary frequency modulation module 903 obtains the frequency modulation coefficient according to the ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and the ratio of the current variable output power of the wind turbine to its maximum variable output power, specifically for: Determining the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power; The frequency modulation coefficient is obtained based on a Sigmoid function according to the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

[0097] Optionally, the energy storage frequency modulation module 905 is used to: Obtain the current charge and discharge power of the energy storage system corresponding to the grid-forming wind turbine, the currently available charge and discharge capacity of the energy storage, the energy storage system power, and the initial value of the energy storage SOC; Obtaining a current energy storage SOC value corresponding to the current moment according to the currently available charge and discharge capacity of the energy storage and the power of the energy storage system; Obtaining a predicted energy storage SOC value corresponding to the next moment according to the charge and discharge power corresponding to the current moment, the current energy storage SOC value, and the initial energy storage SOC value; Obtaining the energy storage output compensation power corresponding to the current moment according to the energy storage SOC prediction value and the currently available charge and discharge capacity of the energy storage; Based on the characteristics of the inverse tangent function, according to the current value of the energy storage SOC, a compensation coefficient corresponding to the current moment is obtained; Obtaining a target energy storage output compensation power corresponding to the current moment according to the energy storage output compensation power, the compensation coefficient corresponding to the current moment, and the maximum available capacity of the energy storage; The charge and discharge power at the current moment is corrected according to the target energy storage output compensation power corresponding to the current moment to obtain the corrected charge and discharge power.

[0098] Optionally, the energy storage frequency modulation module 905 obtains the charge and discharge power corresponding to the current moment, specifically for: Obtaining a droop coefficient corresponding to the current moment according to the current energy storage SOC value, the initial energy storage SOC value, and the grid frequency difference; Obtaining a storage energy output reference power corresponding to the current moment according to the droop coefficient corresponding to the current moment and the grid frequency difference; The charge and discharge power corresponding to the current moment is obtained according to the energy storage output reference power corresponding to the current moment.

[0099] The embodiment of the present application provides a grid-type wind-storage frequency regulation control device based on optimization of rotor kinetic energy and energy storage SOC. Its specific implementation process can be found in the above-mentioned method embodiment. Its implementation principle and technical effects are similar, and this embodiment will not be repeated here.

[0100] Figure 14 This is a schematic diagram of the structure of an electronic device provided in one embodiment of the present application. Figure 14 As shown, the electronic device includes: a processor 1010 and a memory 1020.

[0101] The memory 1020 stores computer-executable instructions.

[0102] The processor 1010 executes the computer-executable instructions stored in the memory 1020 , so that the processor 1010 executes the method described in any of the above embodiments.

[0103] The specific implementation process of the electronic device provided in the embodiment of the present application can be found in the above-mentioned method embodiment. Its implementation principle and technical effects are similar, and will not be repeated here in this embodiment.

[0104] In the above Figure 14 In the illustrated embodiment, it should be understood that the processor may be a central processing unit (CPU), other general-purpose processors, digital signal processors (DSP), application-specific integrated circuits (ASIC), etc. The general-purpose processor may be a microprocessor or any conventional processor. The steps of the method disclosed in the present invention may be directly implemented by a hardware processor or implemented by a combination of hardware and software modules in the processor.

[0105] The memory may include a high-speed RAM memory, and may also include a non-volatile storage NVM, such as at least one disk storage.

[0106] The bus can be an Industry Standard Architecture (ISA) bus, a Peripheral Component Interconnect (PCI) bus, or an Extended Industry Standard Architecture (EISA) bus. Buses can be classified into address buses, data buses, and control buses. For ease of illustration, the buses in the drawings of this application are not limited to just one bus or just one type of bus.

[0107] An embodiment of the present application further provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer-executable instructions. When a processor executes the computer-executable instructions, the method shown in the above method embodiment is implemented.

[0108] The computer-readable storage medium mentioned above can be implemented by any type of volatile or non-volatile memory device, or a combination thereof, such as static random access memory (SRAM), electrically erasable programmable read-only memory (EEPROM), erasable programmable read-only memory (EPROM), programmable read-only memory (PROM), read-only memory (ROM), magnetic storage, flash memory, magnetic disk, or optical disk. The computer-readable storage medium can be any available medium that can be accessed by a general-purpose or special-purpose computer.

[0109] An exemplary readable storage medium is coupled to a processor so that the processor can read information from the readable storage medium and write information to the readable storage medium. Of course, the readable storage medium can also be an integral part of the processor. The processor and the readable storage medium can be located in an application specific integrated circuit (ASIC). Of course, the processor and the readable storage medium can also exist in a device as discrete components.

[0110] Those skilled in the art will appreciate that all or part of the steps in the above-described method embodiments can be implemented using hardware associated with program instructions. The aforementioned program can be stored in a computer-readable storage medium. When executed, the program performs the steps of the above-described method embodiments. The aforementioned storage medium includes various media capable of storing program code, such as ROM, RAM, magnetic disks, or optical disks.

[0111] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present application, rather than to limit them. Although the present application has been described in detail with reference to the above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above embodiments, or make equivalent replacements for some or all of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the scope of the technical solutions of the embodiments of the present application.

Claims

1. A grid-type wind-storage frequency modulation control method based on rotor kinetic energy and energy storage SOC optimization, characterized in that: include: When the grid frequency difference is greater than or equal to the frequency difference in the frequency regulation dead zone, the grid-connected wind turbine is controlled to perform wind-storage combined frequency regulation. When the wind-storage combined frequency regulation is performed, the wind turbine is controlled to operate in the load-shedding power standby frequency regulation PRFC mode. Obtaining an actual system angular frequency and a disturbance value of the wind turbine group, and obtaining a wind turbine output power according to the actual system angular frequency and the disturbance value; Obtaining a system angular frequency change according to the actual system angular frequency and the rated angular frequency of the grid-forming wind turbine; Obtaining a wind turbine frequency modulation output power change according to the system angular frequency change and the frequency modulation coefficient, wherein the frequency modulation coefficient is used to dynamically adjust the frequency modulation capability of the grid-forming wind turbine; An output reference power is obtained according to the wind turbine output power and the change in the wind turbine frequency modulation output power, so as to perform frequency modulation according to the output reference power.

2. The method according to claim 1, characterized in that Before obtaining the wind turbine frequency modulation output power variation according to the system angular frequency variation and the frequency modulation coefficient, the method further includes: Obtain the maximum speed change, minimum speed change, rotor speed deviation of the network wind turbine during the current frequency modulation process, as well as the minimum and maximum limit frequency modulation power; Obtaining a proportion of the wind turbine's current adjustable kinetic energy relative to its maximum adjustable kinetic energy based on the maximum speed change, the minimum speed change, the rotor speed deviation of the grid-connected wind turbine during the current frequency modulation process, and the grid frequency difference; Obtaining a ratio of the wind turbine's current variable output power to its maximum variable output power according to the minimum limit frequency modulation power, the maximum limit frequency modulation power, and the grid frequency difference; The frequency modulation coefficient is obtained according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

3. The method according to claim 2, characterized in that Obtaining the frequency modulation coefficient according to a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power includes: Determining the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power; The frequency modulation coefficient is obtained based on a Sigmoid function according to the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power.

4. The method according to claim 3, characterized in that Obtaining the frequency modulation coefficient based on a Sigmoid function according to the smaller value of a ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and a ratio of the current variable output power of the wind turbine to its maximum variable output power includes: The frequency modulation coefficient is obtained according to a target formula based on a Sigmoid function based on the smaller value of the ratio of the current adjustable kinetic energy of the wind turbine to its maximum adjustable kinetic energy and the ratio of the current variable output power of the wind turbine to its maximum variable output power. The target formula is: ； in, f =min[ k r , k p ],parameter a Control the rate of change, parameter b determines the starting degree of fan participation in frequency regulation.

5. The method according to claim 4, characterized in that The parameters a The value is 0.217, the parameter b The value of is 2.

536.

6. The method according to any one of claims 1 to 5, characterized in that Obtaining the wind turbine output power according to the actual system angular frequency and the disturbance amount includes: Obtaining an initial wind turbine output power according to the actual system angular frequency and the disturbance amount; The wind turbine output power is obtained according to the initial wind turbine output power and the limit frequency modulation power.

7. The method according to any one of claims 1 to 5, characterized in that Also includes: Obtain the current charge and discharge power of the energy storage system corresponding to the grid-forming wind turbine, the currently available charge and discharge capacity of the energy storage, the energy storage system power, and the initial value of the energy storage SOC; Obtaining a current energy storage SOC value corresponding to the current moment according to the currently available charge and discharge capacity of the energy storage and the power of the energy storage system; Obtaining a predicted energy storage SOC value corresponding to the next moment according to the charge and discharge power corresponding to the current moment, the current energy storage SOC value, and the initial energy storage SOC value; Obtaining the energy storage output compensation power corresponding to the current moment according to the energy storage SOC prediction value and the currently available charge and discharge capacity of the energy storage; Based on the characteristics of the inverse tangent function, according to the current value of the energy storage SOC, a compensation coefficient corresponding to the current moment is obtained; Obtaining a target energy storage output compensation power corresponding to the current moment according to the energy storage output compensation power, the compensation coefficient corresponding to the current moment, and the maximum available capacity of the energy storage; The charge and discharge power at the current moment is corrected according to the target energy storage output compensation power corresponding to the current moment to obtain the corrected charge and discharge power.

8. The method according to claim 7, characterized in that Obtaining the charge and discharge power corresponding to the current moment includes: Obtaining a droop coefficient corresponding to the current moment according to the current energy storage SOC value, the initial energy storage SOC value, and the grid frequency difference; Obtaining a storage energy output reference power corresponding to the current moment according to the droop coefficient corresponding to the current moment and the grid frequency difference; The charge and discharge power corresponding to the current moment is obtained according to the energy storage output reference power corresponding to the current moment.

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