A flywheel energy storage virtual synchronous capacitor phase lead compensation control method, system, device and medium

Abstract

The application discloses a flywheel energy storage virtual synchronous capacitor phase lead compensation control method, system, device and medium, and belongs to the technical field of energy storage control of a power system, and comprises the following steps: constructing a disturbance severity index based on a voltage variation trend signal and a voltage deviation of a common connection point; adaptively adjusting a virtual capacitor parameter to obtain an adaptive virtual capacitor parameter; generating a reactive power instruction through phase lead compensation processing based on the adaptive virtual capacitor parameter and the voltage variation trend signal; and driving a flywheel energy storage converter to output reactive power based on the reactive power instruction. The application extracts a voltage variation trend signal and combines phase lead compensation processing to predict a change direction at the initial stage of voltage drop and generate a reactive power instruction in advance, thereby shortening a reactive response time delay. According to segmented smooth limiting of a state of charge of a flywheel energy storage system, current impact caused by instruction step truncation is avoided, and the operation safety of a flywheel mechanical system is ensured.

Description

Technical Field

[0001] This invention relates to the field of power system energy storage control technology, specifically to a method, system, equipment, and medium for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor. Background Technology

[0002] With the high proportion of new energy sources being integrated into the grid, traditional synchronous generators are gradually being phased out, leading to a significant decrease in the short-circuit capacity and voltage support capability of the power system. Flywheel energy storage systems, due to their fast response speed, long cycle life, and high power density, are suitable for short-term, high-frequency frequency and voltage regulation of the power grid.

[0003] In existing technologies, virtual synchronous generator control mainly focuses on active power-frequency regulation. Its reactive power-voltage loop often employs a fixed droop coefficient or a simple virtual capacitor strategy, typically generating reactive power commands based solely on voltage deviation or the first-order rate of change of voltage. This approach is essentially a passive following control: it only activates when the voltage has already changed significantly or deviated, failing to predict the trend of voltage drop and inject reactive power in advance.

[0004] Furthermore, existing virtual capacitor parameters are mostly fixed values, making it difficult to adaptively match support requirements under minor disturbances and severe faults. This can easily lead to overcompensation during minor disturbances or insufficient support during severe faults. Therefore, there is an urgent need for a flywheel energy storage voltage support control method that can sense voltage change trends, generate reactive power commands in advance, adaptively adjust parameters, and has noise immunity. Summary of the Invention

[0005] In view of the above-mentioned problems, the present invention provides a method, system, device and medium for phase lead compensation control of flywheel energy storage virtual synchronous capacitor.

[0006] Therefore, the technical problem solved by this invention is: how to use voltage change trend signals to realize the early generation of reactive power commands for flywheel energy storage, shorten the reactive power response delay under voltage drop disturbances, and improve the dynamic support capability of weak grid voltage.

[0007] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor, comprising, The voltage amplitude at the point of common coupling is processed to obtain voltage deviation and voltage change trend signals; Based on voltage change trend signals and voltage deviation, a disturbance severity index is constructed. The disturbance severity index is used to adaptively adjust the virtual capacitance parameter to obtain the adaptive virtual capacitance parameter. Based on adaptive virtual capacitor parameters and voltage change trend signals, reactive power commands are generated after phase lead compensation processing. The flywheel energy storage converter is driven by reactive power command to output reactive power.

[0008] As a preferred embodiment of the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage according to the present invention, wherein: the processing of the voltage amplitude at the point of common coupling to obtain voltage deviation and voltage change trend signals includes: The voltage amplitude is low-pass filtered to obtain the filtered voltage. The voltage deviation is obtained by comparing the filtered voltage with the rated voltage; The first-order rate of change and the second-order rate of change of voltage are obtained by differential calculation based on the values ​​of the filtered voltage at continuous sampling times. The second-order rate of change of voltage is averaged over a preset time window to output a voltage change trend signal.

[0009] As a preferred embodiment of the method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor according to the present invention, wherein obtaining the adaptive virtual capacitor parameters includes: Weights are assigned to the voltage change trend signal and the voltage deviation, and the weighted trend component is combined with the deviation component to obtain the disturbance severity index. The adjustment amount is determined based on the nonlinear mapping relationship between the disturbance severity index, the virtual capacitance boundary parameters, and the disturbance threshold. The adjustment amount is combined with the reference virtual capacitance parameter to obtain the adaptive virtual capacitance parameter.

[0010] As a preferred embodiment of the method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor according to the present invention, the step of generating reactive power commands based on adaptive virtual capacitor parameters and voltage change trend signals through phase lead compensation processing includes: The capacitance response term is obtained based on the adaptive virtual capacitance parameters and the first-order rate of change of voltage. The voltage change trend signal is subjected to phase lead compensation processing, and the trend compensation term is obtained based on the result of the compensation processing and the adaptive virtual capacitance parameter. The voltage deviation is proportionally processed to obtain a steady-state adjustment term; The reactive power command is obtained by superimposing the capacitor response term, trend compensation term, and steady-state adjustment term.

[0011] As a preferred embodiment of the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage according to the present invention, wherein: the reactive power output of the flywheel energy storage converter driven by the reactive power command includes: In response to the reactive power command, the reactive power command is segmented, smoothed, and limited according to the state of charge of the flywheel energy storage system to obtain the reactive power execution command. Based on the magnitude of the grid voltage, the reactive power execution command is converted into a reactive current command; The reactive current command is controlled by the inner current loop to drive the flywheel energy storage converter to output reactive power.

[0012] As a preferred embodiment of the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage according to the present invention, wherein: the segmented smoothing limiting includes: When the state of charge is less than the preset lower threshold of charge, the reactive power command is reduced by the first linear coefficient. When the state of charge is greater than the preset upper threshold of charge, the reactive power command is reduced by the second linear coefficient. When the state of charge is between the preset lower charge threshold and the preset upper charge threshold, the reactive power command does not decrease.

[0013] As a preferred embodiment of the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage according to the present invention, the low-pass filter includes a first-order low-pass filter. The cutoff frequency of the first-order low-pass filter is set according to the harmonic content of the power grid.

[0014] This invention provides a system for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage.

[0015] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a system for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, comprising: a voltage processing module, an index construction module, a parameter adaptive module, an instruction generation module, and a drive execution module; The voltage processing module is used to process the voltage amplitude at the common connection point to obtain voltage deviation and voltage change trend signals; The index construction module is used to construct a disturbance severity index based on the voltage change trend signal and the voltage deviation; The parameter adaptive module is used to adaptively adjust the virtual capacitor parameters in response to the disturbance severity index to obtain adaptive virtual capacitor parameters. The instruction generation module is used to generate reactive power instructions based on the adaptive virtual capacitor parameters and the voltage change trend signal, after phase lead compensation processing. The drive execution module is used to drive the flywheel energy storage converter to output reactive power based on reactive power commands.

[0016] The present invention provides a computer device, including a memory and a processor. The memory stores a computer program, and the processor executes the computer program to implement the steps of the method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor.

[0017] The present invention provides a computer-readable storage medium having a computer program stored thereon, wherein the computer program, when executed by a processor, implements the steps of the method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor.

[0018] The beneficial effects of this invention are as follows: By extracting the voltage change trend signal and combining it with phase lead compensation processing, this invention predicts the direction of change in the early stage of voltage drop and generates reactive power commands in advance, thus shortening the reactive power response delay. The low-pass filtering of the voltage amplitude and the moving average processing of the second-order rate of change of voltage suppress the high-frequency noise amplified by differential operations, ensuring the stability of control commands in noisy environments. The segmented smoothing and limiting based on the state of charge of the flywheel energy storage system avoids current surges caused by command step cutoff, ensuring the safe operation of the flywheel mechanical system. Attached Figure Description

[0019] To more clearly illustrate the technical solutions of the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying 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.

[0020] Figure 1 The above is a flowchart of a method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, provided as an embodiment of the present invention.

[0021] Figure 2 The diagram below illustrates the principle of reactive power command superposition generation for a method of phase advance compensation control of a virtual synchronous capacitor for flywheel energy storage, provided in one embodiment of the present invention.

[0022] Figure 3 The flowchart illustrates the reactive power execution command generation and judgment process of a method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, provided in one embodiment of the present invention. Detailed Implementation

[0023] To make the present invention more apparent and understandable, the specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the protection scope of the present invention.

[0024] Example 1, referring to Figure 1 This is one embodiment of the present invention, which provides a method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor, comprising: To overcome the shortcomings of existing virtual synchronous control, such as reactive power response lagging behind voltage changes and inability to predict voltage dip trends, this embodiment dynamically adjusts virtual capacitor parameters based on voltage change trend signals and voltage deviations, and introduces phase lead compensation to generate reactive power commands in advance, thereby achieving active support of grid voltage by flywheel energy storage. Specifically, it includes the following steps: S1. Process the voltage amplitude at the common coupling point to obtain the voltage deviation and voltage change trend signals; S2. Based on the voltage change trend signal and voltage deviation, a disturbance severity index is constructed; the disturbance severity index is used to adaptively adjust the virtual capacitance parameter to obtain the adaptive virtual capacitance parameter; S3. Based on the adaptive virtual capacitor parameters and voltage change trend signal, a reactive power command is generated after phase lead compensation processing. S4. Drive the flywheel energy storage converter to output reactive power based on reactive power command.

[0025] Example 2, an embodiment of the present invention, provides a method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor based on the previous embodiment, comprising: Step S1: Process the voltage amplitude at the point of common coupling to obtain the voltage deviation and voltage change trend signal, including the following steps S11~S13: S11. Perform low-pass filtering on the voltage amplitude to obtain the filtered voltage; obtain the voltage deviation by comparing the filtered voltage with the rated voltage.

[0026] Specifically, the three-phase voltage at the point of common coupling (PCC) is collected. The voltage amplitude V is extracted through a phase-locked loop (PLL).

[0027] A first-order low-pass filter is applied to the voltage amplitude V, and the transfer function is: s is the Laplace operator. The cutoff angular frequency of the filter. Set the frequency to 1.0kHz (range 0.5~2.0kHz) to obtain the filter voltage. .

[0028] Calculate the rated voltage deviation: ,in The rated voltage (per unit value is 1.0 pu) is used to obtain the voltage deviation. .

[0029] S12. Based on the values ​​of the filtered voltage at continuous sampling times, differential calculation is performed to obtain the first-order rate of change and the second-order rate of change of the voltage.

[0030] Specifically, the current rate of voltage change is obtained by calculating the first-order rate of change of voltage, and the second-order rate of change of voltage is used to obtain the current rate of change of voltage. Determine the acceleration trend of voltage changes to identify whether the voltage is in a state of accelerated decline, accelerated recovery, or stability.

[0031] The first-order rate of change of voltage is discretized using the backward difference method: Second rate of change of voltage: in, To control the period, the value ranges from 5 to 20 ms, with 10 ms being preferred; k is the index of the current sampling time.

[0032] First-order rate of change of voltage This will be used in subsequent steps to generate the capacitor response term in the reactive power command; second-order rate of change of voltage. Then proceed to step S13 to obtain the voltage change trend signal.

[0033] S13. Perform a moving average on the values ​​of the second-order rate of change of voltage within a preset time window, and output a voltage change trend signal.

[0034] Specific to Apply a moving average filter with a window width of N = 3 to 5, that is, take the arithmetic mean of the second-order voltage change rate over the current time and the previous N sampling times, to obtain the smoothed second-order voltage change rate at time k after the moving average filter. : Where i = 0, 1, ..., N-1, The second-order rate of change of the filtered voltage after N-point moving average processing is represented at the k-th sampling time, serving as the voltage change trend signal; N is the moving average window length; and i is the summation index.

[0035] To suppress high-frequency measurement noise amplification and improve control robustness, This signal is output as a voltage change trend signal. This voltage change trend signal provides a basis for subsequent disturbance identification and phase advance compensation, enabling proactive sensing of grid voltage fluctuations.

[0036] Step S2: Based on the voltage change trend signal and voltage deviation, a disturbance severity index is constructed. The disturbance severity index adaptively adjusts the virtual capacitance parameters to obtain adaptive virtual capacitance parameters, including the following steps S21~S22: S21. Assign weights to the voltage change trend signal and the voltage deviation respectively, and combine the weighted trend component with the deviation component to obtain the disturbance severity index.

[0037] Voltage change trend signal Assign first weight A second weight w2 is assigned to the voltage deviation ΔV. The voltage change trend signal after weighting is summed with the voltage deviation after weighting to obtain the disturbance severity index α. in, In the preferred embodiment =0.6、 =0.4.

[0038] Weighting coefficient The selection of the flywheel energy storage system is based on the matching relationship between the electromechanical time constant and the short-circuit impedance of the power grid. It was determined through multi-condition simulation calibration, achieving an optimal balance in terms of voltage sag suppression, response speed, and noise robustness. In practical engineering, the weights can be fine-tuned through offline simulation or online identification methods according to the specific grid strength and flywheel parameters.

[0039] In this embodiment, assigning weights is specifically manifested as follows: first, the voltage change trend signal is... The trend component is obtained by normalizing the voltage deviation ΔV by dividing it by the rated voltage VN. With deviation component Then multiply by the first weight respectively With the second weight The summation yields the disturbance severity index α.

[0040] S22. Determine the adjustment amount according to the nonlinear mapping relationship between the disturbance severity index, the virtual capacitance boundary parameters, and the disturbance threshold; combine the adjustment amount with the baseline virtual capacitance parameters to obtain the adaptive virtual capacitance parameters.

[0041] Based on the voltage disturbance severity index α, the virtual capacitance parameters are adaptively adjusted according to the following formula to obtain the adaptive virtual capacitance parameters. : in, =0.2pu is the baseline virtual capacitance parameter; =0.8pu is the maximum virtual capacitance to ensure support capability under large disturbances; The disturbance trigger threshold, calibrated through simulation, This represents the minimum allowable value for the virtual capacitance parameter, ensuring system stability under small disturbances. Together they constitute the preset boundary range of the virtual capacitance parameters, and the adaptive virtual capacitance parameters... The value of is limited by this boundary range.

[0042] Step S3: Based on the adaptive virtual capacitor parameters and voltage change trend signal, a reactive power command is generated after phase lead compensation processing, referring to... Figure 2 Includes the following steps S31~S34: S31. Based on the adaptive virtual capacitor parameters and the first-order rate of change of voltage, the capacitor response term is obtained.

[0043] Specifically, the expression for the capacitance response term is: Capacitor response term = This method generates a model based on the product of the first-order rate of change of voltage and the adaptive virtual capacitor parameters, simulating the capacitance characteristics of a synchronous motor and providing basic dynamic reactive power support.

[0044] S32. Perform phase lead compensation processing on the voltage change trend signal, and obtain the trend compensation term based on the result of the compensation processing and the adaptive virtual capacitor parameters.

[0045] The voltage change trend signal is processed by the phase lead transfer function. After processing, the results are compared with the adaptive virtual capacitance parameters. Multiplying these together yields the trend compensation term: Trend compensation term = Phase lead transfer function: Wherein, θ is the phase lead angle, ranging from 15° to 30°, preferably 25°; τ is the lead time constant, ranging from 15 to 30 ms, preferably 20 ms; β is the attenuation coefficient, calculated by β=(1-sinθ) / (1+sinθ), used to limit high-frequency gain and ensure system stability.

[0046] This approach introduces information characterizing the acceleration trend of voltage changes. After processing by the phase lead transfer function, reactive power commands are generated in advance at the initial stage of voltage changes, realizing the control transformation from passive following to active prediction.

[0047] It should be noted that the original second-order rate of change of voltage, after being processed by the S13 moving average filter, outputs a voltage change trend signal. In this embodiment, the phase lead compensation processing uniformly adopts... (i.e., the trend signal after noise reduction processing), rather than the unfiltered signal. Due to the lead-lag transfer function It has gain amplification characteristics in the high-frequency band, and is filtered by moving average. As input, it can prevent high-frequency measurement noise from being further amplified, thus improving the overall noise immunity.

[0048] Discretization implementation: using the bilinear transform method ,get z-domain expression: It facilitates real-time calculations by digital signal processors (DSPs).

[0049] It should be further noted that the phase lead compensation process, in addition to employing the lead-lag transfer function, also utilizes other technologies. Alternatively, a differential lead network processing method based on a preset gain coefficient can be used: the voltage change trend signal is differentiated to obtain its rate of change, this rate of change is multiplied by the preset gain coefficient and then summed with itself to form a processing result with phase lead effect, which is then multiplied by the adaptive virtual capacitor parameter to obtain the trend compensation term. This method has a simpler structure and is suitable for application scenarios with lower requirements for phase lead accuracy.

[0050] S33. The voltage deviation is proportionally processed to obtain a steady-state adjustment term.

[0051] Steady-state adjustment term = in, This is the voltage droop factor, ranging from 100 to 300 kvar / kV, preferably 200 kvar / kV. This factor is proportionally adjusted based on the voltage deviation ΔV to eliminate steady-state errors and ensure that the voltage accurately recovers to the rated value after disturbance elimination.

[0052] S34. The capacitor response term, trend compensation term, and steady-state adjustment term are superimposed to obtain the reactive power command.

[0053] Reactive power command It consists of the above three items superimposed: = + · · + The reactive power command obtained in step S34 It will be used as the input for step S4 (driving the flywheel energy storage converter to output reactive power based on the reactive power command).

[0054] Step S4: Drive the flywheel energy storage converter to output reactive power based on the reactive power command, including the following steps S41~S43: S41 responds to the reactive power command by performing segmented smoothing and limiting of the reactive power command according to the state of charge of the flywheel energy storage system, thereby obtaining the reactive power execution command.

[0055] Specifically, refer to Figure 3 Based on the State of Charge (SOC) of the flywheel energy storage system, a three-stage linear smooth transition strategy is used to limit the reactive power command Qref, resulting in the reactive power execution command. : in, (Refer to the state of charge, center of the working area); (Minimum permissible state of charge to prevent over-discharge). This limiting logic avoids current surges caused by step cutoff, ensuring the safety of the flywheel mechanical system.

[0056] When SOC < When the charge level is below the preset threshold, the first linear coefficient is applied. Adjusting Qref yields .

[0057] When SOC > 1 - SOCref (i.e., higher than the preset charge threshold), the second linear coefficient is applied. right Adjustments were made to obtain .

[0058] when When the charge level is between the preset lower charge threshold and the preset upper charge threshold, directly apply the following: As Output.

[0059] S42 converts the reactive power execution command into a reactive current command based on the magnitude of the grid voltage.

[0060] Based on the magnitude of the grid voltage, the reactive power execution command is executed. Convert to reactive current command in dq coordinate system : Where, assuming , .

[0061] The voltage amplitude V of the grid voltage here corresponds to the voltage amplitude V extracted by the phase-locked loop (PLL) in S11 (without subsequent low-pass filtering in S11). It is a different quantity from the filtered voltage in S11 and should not be used interchangeably.

[0062] S43 controls the reactive current command through the inner current loop, driving the flywheel energy storage converter to output reactive power.

[0063] The inner current loop employs feedforward decoupled PI control for reactive current commands. Perform tracking and control: Among them, the proportionality coefficient =1.2 (range 0.5~2.0); integral coefficient =50 (value range 20-100); control bandwidth is set to 800Hz (value range 500-1000Hz).

[0064] ω is the actual measured value of the q-axis current; L is the grid angular frequency; L is the filter inductance on the converter side. This is the actual measured value of the d-axis current; This is the d-axis voltage feedforward term (Vd≈V, i.e., the amplitude of the grid voltage).

[0065] Using Space Vector Pulse Width Modulation (SVPWM) It is converted into a drive signal to control the flywheel energy storage converter to output reactive power, thereby achieving dynamic voltage support.

[0066] Example 3 is an embodiment of the present invention. This embodiment provides a system for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, including a voltage processing module, an index construction module, a parameter adaptive module, an instruction generation module, and a drive execution module. The voltage processing module is used to process the voltage amplitude at the common connection point to obtain voltage deviation and voltage change trend signals; The index construction module is used to construct a disturbance severity index based on the voltage change trend signal and the voltage deviation; The parameter adaptive module is used to adaptively adjust the virtual capacitor parameters in response to the disturbance severity index to obtain adaptive virtual capacitor parameters. The instruction generation module is used to generate reactive power instructions based on the adaptive virtual capacitor parameters and the voltage change trend signal, after phase lead compensation processing. The drive execution module is used to drive the flywheel energy storage converter to output reactive power based on reactive power commands.

[0067] This embodiment also provides an electronic device applicable to a method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, comprising: a memory and a processor; the memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions to implement the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage as proposed in the above embodiment.

[0068] This embodiment also provides a storage medium storing a computer program that, when executed by a processor, implements a method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as proposed in the above embodiments.

[0069] The storage medium proposed in this embodiment and the method for implementing a virtual synchronous capacitor phase advance compensation control for flywheel energy storage proposed in the above embodiments belong to the same inventive concept. Technical details not described in detail in this embodiment can be found in the above embodiments, and this embodiment has the same beneficial effects as the above embodiments.

[0070] Based on the above description of the implementation methods, those skilled in the art can clearly understand that the present invention can be implemented using software and necessary general-purpose hardware, and of course, it can also be implemented using hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of the present invention, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a computer-readable storage medium, such as a computer floppy disk, read-only memory (ROM), random access memory (RAM), flash memory, hard disk, or optical disk, etc., including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods of the various embodiments of the present invention.

[0071] It should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor, characterized in that, include: The voltage amplitude at the point of common coupling is processed to obtain voltage deviation and voltage change trend signals; Based on voltage change trend signals and voltage deviation, a disturbance severity index is constructed. The disturbance severity index is used to adaptively adjust the virtual capacitance parameter to obtain the adaptive virtual capacitance parameter. Based on adaptive virtual capacitor parameters and voltage change trend signals, reactive power commands are generated after phase lead compensation processing. The flywheel energy storage converter is driven by reactive power command to output reactive power.

2. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 1, characterized in that, The process of processing the voltage amplitude at the common coupling point to obtain voltage deviation and voltage change trend signals includes: The voltage amplitude is low-pass filtered to obtain the filtered voltage. The voltage deviation is obtained by comparing the filtered voltage with the rated voltage; The first-order rate of change and the second-order rate of change of voltage are obtained by differential calculation based on the values ​​of the filtered voltage at continuous sampling times. The second-order rate of change of voltage is averaged over a preset time window to output a voltage change trend signal.

3. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 2, characterized in that, The obtained adaptive virtual capacitance parameters include: Weights are assigned to the voltage change trend signal and the voltage deviation, and the weighted trend component is combined with the deviation component to obtain the disturbance severity index. The adjustment amount is determined based on the nonlinear mapping relationship between the disturbance severity index, the virtual capacitance boundary parameters, and the disturbance threshold. The adjustment amount is combined with the reference virtual capacitance parameter to obtain the adaptive virtual capacitance parameter.

4. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 3, characterized in that, The process of generating reactive power commands based on adaptive virtual capacitor parameters and voltage change trend signals, after phase lead compensation processing, includes: The capacitance response term is obtained based on the adaptive virtual capacitance parameters and the first-order rate of change of voltage. The voltage change trend signal is subjected to phase lead compensation processing, and the trend compensation term is obtained based on the result of the compensation processing and the adaptive virtual capacitance parameter. The voltage deviation is proportionally processed to obtain a steady-state adjustment term; The reactive power command is obtained by superimposing the capacitor response term, trend compensation term, and steady-state adjustment term.

5. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 4, characterized in that, The reactive power output of the flywheel energy storage converter driven by the reactive power command includes: In response to the reactive power command, the reactive power command is segmented, smoothed, and limited according to the state of charge of the flywheel energy storage system to obtain the reactive power execution command. Based on the magnitude of the grid voltage, the reactive power execution command is converted into a reactive current command; The reactive current command is controlled by the inner current loop to drive the flywheel energy storage converter to output reactive power.

6. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 5, characterized in that, The segmented smoothing limiting includes: When the state of charge is less than the preset lower threshold of charge, the reactive power command is reduced by the first linear coefficient. When the state of charge is greater than the preset upper threshold of charge, the reactive power command is reduced by the second linear coefficient. When the state of charge is between the preset lower charge threshold and the preset upper charge threshold, the reactive power command does not decrease.

7. The method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor as described in claim 6, characterized in that, The low-pass filter includes a first-order low-pass filter; The cutoff frequency of the first-order low-pass filter is set according to the harmonic content of the power grid.

8. A system for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage, employing the phase lead compensation control method for a virtual synchronous capacitor for flywheel energy storage as described in any one of claims 1 to 7, characterized in that, include: Voltage processing module, index construction module, parameter adaptive module, instruction generation module, and driver execution module; The voltage processing module is used to process the voltage amplitude at the common connection point to obtain voltage deviation and voltage change trend signals; The index construction module is used to construct a disturbance severity index based on the voltage change trend signal and the voltage deviation; The parameter adaptive module is used to adaptively adjust the virtual capacitor parameters in response to the disturbance severity index to obtain adaptive virtual capacitor parameters. The instruction generation module is used to generate reactive power instructions based on the adaptive virtual capacitor parameters and the voltage change trend signal, after phase lead compensation processing. The drive execution module is used to drive the flywheel energy storage converter to output reactive power based on reactive power commands.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method for phase lead compensation control of a flywheel energy storage virtual synchronous capacitor according to any one of claims 1 to 7.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by the processor, it implements the steps of the method for phase lead compensation control of a virtual synchronous capacitor for flywheel energy storage as described in any one of claims 1 to 7.

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