Control method and device for improving sub-super synchronous stability performance of follow-network energy storage converter

Abstract

The invention provides a control method and device for improving the sub-super-synchronous stability of a following grid energy storage converter, belongs to the field of power grid equipment control, and aims at solving the problem that an existing control mode is insufficient in the aspect of improving the sub-super-synchronous oscillation suppression capability, and the invention provides the control method and device for improving the sub-super-synchronous stability of the following grid energy storage converter. Comprising the following steps: carrying out Fourier analysis on an obtained alternating current port voltage instantaneous value to obtain a voltage component amplitude of each frequency, carrying out per-unit processing, and judging whether the frequency is an oscillation frequency or not; the suppression voltage is generated by adopting double proportional-integral control, and the generated suppression voltage is superposed with the conventional generation voltage of the grid-following energy storage converter to generate a reference value of the modulation system; and generating trigger pulses of each IGBT in the grid-following energy storage converter by adopting PWM (Pulse-Width Modulation). According to the invention, each oscillation harmonic can be flexibly suppressed only by using the oscillation harmonic voltage, and the sub-super synchronous stability performance of the grid-following energy storage converter is remarkably improved.

Description

Technical Field

[0001] The present invention belongs to the field of power grid equipment control, and in particular relates to a control method and device for improving sub-super synchronous stability performance of a grid-following energy storage converter. Background Art

[0002] As the construction of my country's new power system gradually deepens, the application of large-scale energy storage in the power grid will become more and more extensive. In particular, in order to solve the sub-supersynchronous oscillation problem caused by new energy grid-connected equipment such as wind power and photovoltaic power, the application of energy storage converters will become more necessary.

[0003] At present, in order to suppress the oscillation problems caused by the grid connection of new energy sources such as wind power and photovoltaic power, the suppression control based on the reactive power compensation principle has been widely adopted and applied. Taking the application of chain STATCOM as an example, existing studies often adjust the damping characteristics of the access system containing power electronic equipment by adjusting the reactive power represented by the grid connection point voltage and the active power represented by the active power and frequency as the adjustment target. Existing studies have proposed the concept of active dampers, which limit the error signal to the grid connection point voltage; while another existing study considers the influence of phase shift angle and installation position on the damping effect, and explains the principle of damped oscillation from the perspective of energy. In addition, there are existing studies that use active damping control methods, mainly using the current on the AC side of the converter to form damping control through PI control; however, most of the current research focuses on reactive compensation devices such as STATCOM, and there is relatively little research on active devices such as energy storage converters in improving the ability to suppress sub-supersynchronous oscillations. Summary of the invention

[0004] In response to the problems existing in the prior art, the present application proposes a control method and device for improving the sub-supersynchronous stability performance of a grid-connected energy storage inverter, which can fully utilize the impedance shaping capability of the energy storage inverter, thereby achieving flexible shaping of its internal equivalent impedance on the basis of ensuring the active and reactive output of the energy storage inverter, effectively suppressing the converter oscillation mode under various operating conditions, and further improving the operating safety and system interaction stability of the grid-connected energy storage system.

[0005] The present application proposes a control method for improving the sub-super synchronous stability performance of a grid-connected energy storage converter, comprising: S1, measuring and obtaining the instantaneous value of the AC port voltage of the grid-connected energy storage converter, performing Fourier analysis on the obtained instantaneous value of the AC port voltage, and obtaining the amplitude of the voltage component of each frequency; S2, the voltage component amplitudes of each frequency are normalized to obtain normalized results; S3, judging whether the AC port voltage of the grid-connected energy storage converter is at an oscillation frequency according to the normalization result; When the frequency belongs to the oscillation harmonic, turn on the oscillation suppression switch; When the frequency does not belong to the oscillation frequency, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; The oscillation suppression switch may be a real switch in a physical structure or a software switch signal in control software, and is usually in the form of a software switch.

[0006] S4, for the harmonic voltage driving the oscillation suppression switch, a dual proportional-integral control is used to generate its suppression voltage, and the generated suppression voltage is superimposed on the conventional generation voltage of the grid-following energy storage converter to generate a reference value of the modulation system; wherein the conventional generation voltage is obtained in the following manner: wherein the conventional generation voltage is obtained in the following manner: through the outer loop control and the inner loop control processing, the deviation between the active power reference value set by the grid-following energy storage converter and the actual active power value measured at the AC port and the deviation between the reactive power reference value set by the grid-following energy storage converter and the actual reactive power value measured at the AC port are obtained; S5, based on the reference value of the modulation system, adopts PWM modulation to generate trigger pulses of each IGBT in the grid-following energy storage converter, and realizes sub-super synchronous stability performance improvement control of the grid-following energy storage converter.

[0007] According to the size of the instantaneous value, the working status of the grid-connected energy storage converter at different times can be understood, providing raw data for judging whether it is operating normally and for subsequent optimization control; Fourier analysis can decompose complex periodic voltage signals into the superposition of sinusoidal components of different frequencies. The amplitude of the voltage component of each frequency can be obtained through Fourier analysis, which can accurately understand the size of different frequency components in the AC port voltage; Fourier analysis can also find the size of non-fundamental components. Since non-fundamental components such as harmonics will have adverse effects on the power grid and electrical equipment (such as increasing losses, interfering with communications, etc.), the results after Fourier analysis are very important for evaluating the power quality of the converter output voltage, and help to discover problems such as voltage distortion.

[0008] After normalization, the data obtained is between 0 and 1, which simplifies the data, facilitates calculation, and reduces the requirements for computing performance. Normalized data is usually simpler and more intuitive when calculating and analyzing, which can simplify subsequent calculations and processing processes and is conducive to the formulation of unified standards and specifications to measure power quality.

[0009] The use of dual PI to generate suppression voltage can specifically generate a suppression voltage that is equal to the harmonic voltage in magnitude and opposite in direction. After superimposing it with the conventional generated voltage, it can effectively offset the harmonic voltage, making the output voltage closer to an ideal sine wave and reducing the adverse effects of harmonics on the power grid and connected equipment.

[0010] During operation, the grid-following energy storage inverter needs to be flexibly adjusted according to the conditions of the power grid. By superimposing the suppression voltage and the conventional generated voltage to generate the reference value of the modulation system, the inverter can better adapt to changes in the power grid; control based on the superimposed reference value makes the interaction between the inverter and the power grid more stable, reduces the risk of equipment failure and system power outages caused by harmonic problems, and ensures reliable power supply to the power system.

[0011] Stable and accurate trigger pulses are the key to ensure the stable operation of grid-connected energy storage converters. Accurate parameters of the trigger pulses (such as frequency, phase, amplitude, etc.) can ensure that each IGBT works in coordination and avoid abnormal conditions such as overcurrent and overvoltage.

[0012] Furthermore, the formula for calculating the normalized percentage value is as follows:

[0013] In the formula, The voltage measured at the AC port is decomposed by Fourier transform. i The standardized percentage value of subharmonics; The voltage measured at the AC port is decomposed by Fourier transform. i The amplitude of the subharmonics; V 50 It is the amplitude of the power frequency voltage after Fourier decomposition of the AC port voltage measurement value.

[0014] Furthermore, the standard for judging the resonant frequency is: i The standardized percentage value of the subharmonic determines whether it is an oscillation harmonic. The specific process is as follows: When the AC port voltage measurement value is judged to be Fourier decomposed, the i When the standardized percentage value of the subharmonic is not greater than the oscillation standard threshold, it is judged not to be an oscillation harmonic; when the AC port voltage measurement value is judged to be the first harmonic after Fourier decomposition, i When the normalized percentage value of the subharmonic is greater than the oscillation standard threshold, it is judged to be an oscillation harmonic; the oscillation standard threshold is not higher than 5%.

[0015] The process can also be expressed as: , indicating that it does not belong to oscillation harmonics; if , indicating that it belongs to the oscillation harmonic, among which, The threshold value for the oscillation standard is usually taken as 5% or less.

[0016] Furthermore, the specific control method of the dual proportional-integral control is: For the harmonic voltage driving the oscillation suppression switch, the AC harmonic voltage is first transformed into a DC value under the dq coordinate through abc / dq coordinate transformation, and then compared with 0 respectively to generate the deviation of the dq axis; The generated deviations of the dq axes are respectively used to generate the required suppression voltage additional values ​​of the dq axes through the PI controller; The generated suppression voltage is superimposed on the normal generated voltage of the grid-connected energy storage converter to generate a reference value for the modulation system.

[0017] Furthermore, the specific process of PWM modulation is as follows: the reference value of the modulation system is used as the modulation signal, and the carrier with a frequency of 10k to 20k is used for modulation to obtain the desired PWM waveform, thereby generating the trigger pulse of each IGBT in the grid-connected energy storage converter. When the value of the modulation signal is greater than the value of the saw carrier, the result after pulse modulation is a high level, otherwise, it is a low level.

[0018] PWM modulation stands for pulse width modulation. It modulates the width of a series of pulses to equivalently obtain the required waveform (including shape and amplitude).

[0019] A control device for improving the sub-super synchronous stability performance of a grid-following energy storage converter, comprising: The analysis module measures and obtains the instantaneous value of the AC port voltage of the grid-connected energy storage converter, performs Fourier analysis on the obtained instantaneous value of the AC port voltage, and obtains the amplitude of the voltage component of each frequency; The per-unit standardization module standardizes the voltage component amplitudes of each frequency to obtain a per-unit standardization result; A judgment module determines whether the AC port voltage of the grid-connected energy storage converter is an oscillation frequency according to the normalization result; When the frequency belongs to the oscillation harmonic, turn on the oscillation suppression switch; When the frequency does not belong to the oscillation frequency, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; The suppression module uses dual proportional-integral control to generate the suppression voltage for the harmonic voltage driving the oscillation suppression switch, and superimposes the generated suppression voltage with the conventional generated voltage of the grid-connected energy storage converter to generate a reference value for the modulation system; The improvement module uses PWM modulation based on the reference value of the modulation system to generate trigger pulses for each IGBT in the grid-following energy storage converter, thereby achieving sub-super synchronous stability performance improvement control of the grid-following energy storage converter.

[0020] An electronic device includes a memory and one or more processors, wherein the memory stores executable code, and when the one or more processors execute the executable code, they are used to implement the method for improving the sub-supersynchronous stability performance control of a grid-following energy storage converter.

[0021] Beneficial effects of this application: 1. This application does not require the design of a virtual impedance value, and each oscillation harmonic can be flexibly suppressed by using only the oscillation harmonic voltage; 2. This application can directly suppress the oscillation voltage to 0, significantly improving the sub-super synchronous stability performance of the grid-connected energy storage converter; 3. This application can deeply explore the impedance shaping capability of the grid-connected energy storage converter, not only utilizing its reactive output capability, but also utilizing its active output capability, thus having a wider range of applications. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 Flowchart of the prior art.

[0023] Figure 2 It is a flow chart of this application.

[0024] Figure 3 This is the result diagram of the application example. DETAILED DESCRIPTION

[0025] The technical solutions of the embodiments of the present invention are explained and described below, but the following embodiments are only preferred embodiments of the present invention, not all. Based on the embodiments in the implementation mode, other embodiments obtained by those skilled in the art without creative work are all within the protection scope of the present invention.

[0026] Example 1 like Figure 2 The present application proposes a method for improving the sub-super synchronous stability performance control of a grid-connected energy storage converter, comprising: S1, measure and obtain the instantaneous value of the AC port voltage of the grid-connected energy storage converter v PCC , perform Fourier analysis on the instantaneous value of the AC port voltage to obtain the amplitude of the voltage component at each frequency; The basic principles of Fourier analysis are as follows:

[0027] in, Take the instantaneous value of the AC port voltage ; The frequency is The voltage component amplitude of is the DC component amplitude; , The angular frequencies are The calculation coefficient of the component; T is the industrial frequency period of the AC voltage; t0 is the initial value of the integration; t is the independent variable of the integration.

[0028] S2, the voltage component amplitudes of each frequency are normalized to obtain the normalized results; the normalized percentage value calculation formula is as follows:

[0029] In the formula, The voltage measured at the AC port is decomposed by Fourier transform. i The standardized percentage value of subharmonics; The voltage measured at the AC port is decomposed by Fourier transform. i The amplitude of the subharmonics; V 50 It is the amplitude of the power frequency voltage after Fourier decomposition of the AC port voltage measurement value.

[0030] S3, judging whether the AC port voltage of the grid-connected energy storage converter is at an oscillation frequency according to the normalization result; When it is an oscillation harmonic, turn on the oscillation suppression switch; When it does not belong to oscillation harmonics, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; The standard for judging the resonant frequency is: i The standardized percentage value of the subharmonic determines whether it is an oscillation harmonic. The specific process is as follows: When the AC port voltage measurement value is judged to be Fourier decomposed, the i When the standardized percentage value of the subharmonic is not greater than the oscillation standard threshold, it is judged not to be an oscillation harmonic; when the AC port voltage measurement value is judged to be the first harmonic after Fourier decomposition, i When the normalized percentage value of the subharmonic is greater than the oscillation standard threshold, it is judged to be an oscillation harmonic; the oscillation standard threshold is not higher than 5%.

[0031] The process can also be expressed as: , indicating that it does not belong to oscillation harmonics; if , indicating that it belongs to the oscillation harmonic, among which, The threshold value for the oscillation standard is usually taken as 5% or less.

[0032] S4, for the harmonic voltage driving the oscillation suppression switch, a dual proportional-integral control is used to generate its suppression voltage, and the generated suppression voltage is superimposed on the conventional generated voltage of the grid-following energy storage converter to generate a reference value of the modulation system; the specific control method of the dual proportional-integral control is: For the harmonic voltage driving the oscillation suppression switch, the AC harmonic voltage is first transformed into a DC value under the dq coordinate through abc / dq coordinate transformation, and then compared with 0 to generate the deviation of the dq axis; The generated deviations of the dq axes are respectively used to generate the required suppression voltage additional values ​​of the dq axes through the PI controller; The generated suppression voltage is superimposed on the conventional generated voltage of the grid-following energy storage converter to generate a reference value of the modulation system. The conventional generated voltage is obtained by: through the outer loop control and the inner loop control processing, the deviation between the active power reference value set by the grid-following energy storage converter and the actual active power value measured at the AC port and the deviation between the reactive power reference value set by the grid-following energy storage converter and the actual reactive power value measured at the AC port are obtained.

[0033] S5, based on the reference value of the modulation system, PWM modulation is used to generate trigger pulses for each IGBT in the grid-following energy storage converter, so as to achieve sub-super synchronous stability performance improvement control of the grid-following energy storage converter. The specific process of PWM modulation is as follows: the reference value generated by the modulation system is used as the modulation signal, and a carrier with a frequency of 10k to 20k is used for modulation to obtain the desired PWM waveform. Among them, when the value of the modulation signal is greater than the value of the saw carrier, the result after pulse modulation is a high level, otherwise, it is a low level.

[0034] PWM modulation stands for pulse width modulation. It modulates the width of a series of pulses to equivalently obtain the required waveform (including shape and amplitude).

[0035] According to the size of the instantaneous value, the working status of the grid-connected energy storage converter at different times can be understood, providing raw data for judging whether it is operating normally and for subsequent optimization control; Fourier analysis can decompose complex periodic voltage signals into the superposition of sinusoidal components of different frequencies. The amplitude of the voltage component of each frequency can be obtained through Fourier analysis, which can accurately understand the size of different frequency components in the AC port voltage; Fourier analysis can also find the size of non-fundamental components. Since non-fundamental components such as harmonics will have adverse effects on the power grid and electrical equipment (such as increasing losses, interfering with communications, etc.), the results after Fourier analysis are very important for evaluating the power quality of the converter output voltage, and help to discover problems such as voltage distortion.

[0036] After normalization, the data obtained is between 0 and 1, which simplifies the data, facilitates calculation, and reduces the requirements for computing performance. Normalized data is usually simpler and more intuitive when calculating and analyzing, which can simplify subsequent calculations and processing processes and is conducive to the formulation of unified standards and specifications to measure power quality.

[0037] The use of dual PI to generate suppression voltage can specifically generate a suppression voltage that is equal to the harmonic voltage in magnitude and opposite in direction. After superimposing it with the conventional generated voltage, it can effectively offset the harmonic voltage, making the output voltage closer to an ideal sine wave and reducing the adverse effects of harmonics on the power grid and connected equipment.

[0038] During operation, the grid-following energy storage inverter needs to be flexibly adjusted according to the conditions of the power grid. By superimposing the suppression voltage and the conventional generated voltage to generate the reference value of the modulation system, the inverter can better adapt to changes in the power grid; control based on the superimposed reference value makes the interaction between the inverter and the power grid more stable, reduces the risk of equipment failure and system power outages caused by harmonic problems, and ensures reliable power supply to the power system.

[0039] Stable and accurate trigger pulses are the key to ensure the stable operation of grid-connected energy storage converters. Accurate parameters of the trigger pulses (such as frequency, phase, amplitude, etc.) can ensure that each IGBT works in coordination and avoid abnormal conditions such as overcurrent and overvoltage.

[0040] Combination Figure 1 and Figure 2 From the perspective of current control methods, active damping control principles are mainly used to suppress oscillating harmonics. Usually, only one harmonic frequency can be suppressed, and effective resistance and reactance parameters of active damping need to be designed. This not only results in complex design parameters and lack of universality, but also fails to meet the needs of suppressing wide-band and multi-frequency oscillations in active devices such as energy storage converters when used in power grids.

[0041] Application Examples The effect of the embodiment of the present invention is verified by taking a grid-connected energy storage converter as an example.

[0042] The relevant parameters of the grid-connected energy storage converter are known to be:

[0043] The control method proposed in this application has the following effect on suppressing sub-supersynchronous oscillation: Figure 3 Before the control method of the present application is put into use, the system AC voltage obviously has obvious harmonics; when the control method of the present application is put into use, the harmonic voltage in the system is gradually suppressed and eventually tends to be a sinusoidal quantity; thus, it can be seen that the additional control method for improving the sub-supersynchronous stability performance of the grid-connected energy storage converter proposed in the present application is effective.

[0044] Example 2 A control device for improving the sub-super synchronous stability performance of a grid-following energy storage converter, comprising: The analysis module measures and obtains the instantaneous value of the AC port voltage of the grid-connected energy storage converter, performs Fourier analysis on the obtained instantaneous value of the AC port voltage, and obtains the amplitude of the voltage component of each frequency; The per-unit standardization module standardizes the voltage component amplitudes of each frequency to obtain a per-unit standardization result; A judgment module determines whether the AC port voltage of the grid-connected energy storage converter is an oscillation frequency according to the normalization result; When the frequency belongs to the oscillation harmonic, turn on the oscillation suppression switch; When the frequency does not belong to the oscillation frequency, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; The suppression module uses dual proportional-integral control to generate the suppression voltage for the harmonic voltage driving the oscillation suppression switch, and superimposes the generated suppression voltage with the conventional generated voltage of the grid-connected energy storage converter to generate a reference value for the modulation system; The improvement module uses PWM modulation based on the reference value of the modulation system to generate trigger pulses for each IGBT in the grid-following energy storage converter, thereby achieving sub-super synchronous stability performance improvement control of the grid-following energy storage converter.

[0045] Example 3 An electronic device includes a memory and one or more processors, wherein the memory stores executable code, and when the one or more processors execute the executable code, they are used to implement the method for improving the sub-supersynchronous stability performance control of a grid-following energy storage converter as described in Example 1.

[0046] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the above embodiments, ordinary technicians in the relevant field can still modify or replace the specific implementation methods of the present invention with equivalents. Any modification or equivalent replacement that does not depart from the spirit and scope of the present invention should be included in the scope of protection of the claims of the present invention.

Claims

1. A method for improving the sub-super synchronous stability performance control of a grid-connected energy storage converter, characterized in that: include: S1, measuring and obtaining the instantaneous value of the AC port voltage of the grid-connected energy storage converter, performing Fourier analysis on the obtained instantaneous value of the AC port voltage, and obtaining the amplitude of the voltage component of each frequency; S2, normalizing the voltage component amplitudes of each frequency obtained to obtain normalized results; S3, judging whether each frequency component of the AC port voltage of the grid-connected energy storage converter is an oscillation harmonic according to the normalization result; When it is an oscillation harmonic, turn on the oscillation suppression switch; When it does not belong to oscillation harmonics, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; S4, for the harmonic voltage driving the oscillation suppression switch, a dual proportional-integral control is used to generate its suppression voltage, and the generated suppression voltage is superimposed on the conventional generated voltage of the grid-following energy storage converter to generate a reference value for the modulation system; The conventional generated voltage is obtained by: through the outer loop control and the inner loop control processing, the deviation between the active power reference value set by the grid energy storage converter and the actual active power value measured at the AC port and the deviation between the reactive power reference value set by the grid energy storage converter and the actual reactive power value measured at the AC port are obtained; S5, based on the reference value of the modulation system, adopts PWM modulation to generate trigger pulses of each IGBT in the grid-following energy storage converter, and realizes sub-super synchronous stability performance improvement control of the grid-following energy storage converter.

2. The method for improving the sub-super synchronous stability performance control of the grid-following energy storage converter according to claim 1 is characterized in that: The formula for calculating the standardized percentage value is as follows: In the formula, The voltage measured at the AC port is decomposed by Fourier transform. i The standardized percentage value of subharmonics; The voltage measured at the AC port is decomposed by Fourier transform. i The amplitude of the subharmonics; V 50 It is the amplitude of the power frequency voltage after Fourier decomposition of the AC port voltage measurement value.

3. The method for improving the sub-super synchronous stability performance control of the grid-following energy storage converter according to claim 2 is characterized in that: The standard for judging the resonant frequency is: i The standardized percentage value of the subharmonic determines whether it is an oscillation harmonic. The specific process is as follows: When the AC port voltage measurement value is judged to be Fourier decomposed, the i When the standardized percentage value of the subharmonic is not greater than the oscillation standard threshold, it is judged not to be an oscillation harmonic; when the AC port voltage measurement value is judged to be the first harmonic after Fourier decomposition, i When the normalized percentage value of the subharmonic is greater than the oscillation standard threshold, it is judged to be an oscillation harmonic; the oscillation standard threshold is not higher than 5%.

4. The method for improving the sub-super synchronous stability performance control of the grid-following energy storage converter according to claim 2 is characterized in that: The specific control method of the dual proportional-integral control is: For the harmonic voltage driving the oscillation suppression switch, the AC harmonic voltage is first transformed into a DC value under the dq coordinate through abc / dq coordinate transformation, and then compared with 0 respectively to generate the deviation of the dq axis; The generated deviations of the dq axes are respectively used to generate the required suppression voltage additional values ​​of the dq axes through the PI controller; The generated suppression voltage is superimposed on the normal generated voltage of the grid-connected energy storage converter to generate a reference value for the modulation system.

5. The method for improving the sub-super synchronous stability performance control of the grid-following energy storage converter according to claim 2 is characterized in that: The specific process of the PWM modulation is as follows: the reference value of the modulation system is used as the modulation signal, and a carrier with a frequency of 10k to 20k is used for modulation to obtain the desired PWM waveform, thereby generating a trigger pulse for each IGBT in the grid-connected energy storage converter.

6. A device for improving the sub-super synchronous stability performance of a grid-connected energy storage converter, characterized in that: include: The analysis module measures and obtains the instantaneous value of the AC port voltage of the grid-connected energy storage converter, performs Fourier analysis on the obtained instantaneous value of the AC port voltage, and obtains the amplitude of the voltage component of each frequency; The per-unit standardization module standardizes the voltage component amplitudes of each frequency to obtain a per-unit standardization result; A judgment module determines whether the AC port voltage of the grid-connected energy storage converter is an oscillation frequency according to the normalization result; When the frequency belongs to the oscillation harmonic, turn on the oscillation suppression switch; When the frequency does not belong to the oscillation frequency, turn off the oscillation suppression switch; Among them, the minimum frequency of the oscillation input switch is 1Hz and the maximum frequency is 1000Hz; The suppression module uses dual proportional-integral control to generate the suppression voltage for the harmonic voltage driving the oscillation suppression switch, and superimposes the generated suppression voltage with the conventional generated voltage of the grid-connected energy storage converter to generate a reference value for the modulation system; The improvement module uses PWM modulation based on the reference value of the modulation system to generate trigger pulses for each IGBT in the grid-following energy storage converter, thereby achieving sub-super synchronous stability performance improvement control of the grid-following energy storage converter.

7. An electronic device, characterized in that: It comprises a memory and one or more processors, wherein the memory stores executable codes, and when the one or more processors execute the executable codes, they are used to implement the method for improving the sub-supersynchronous stability performance control of a grid-following energy storage converter as described in any one of claims 1 to 5.

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