A voltage flicker suppression method and device for a new energy grid-connected system

Abstract

The application relates to the technical field of voltage flicker suppression, in particular to a voltage flicker suppression method and device for a new energy grid-connected system. The device comprises a signal acquisition and preprocessing unit for signal acquisition and processing; a characteristic analysis unit for grid parameter characteristic analysis in the grid-connected system; a response time adjusting unit for response time adjustment of grid parameter data under different frequency bands; and a compensation amount calculation unit for determining the priority order of the matching response time by using the energy of the frequency band components. The application aims to efficiently suppress voltage flicker in the grid-connected system and improve the grid voltage quality.

Description

Technical Field

[0001] This application relates to the field of voltage flicker suppression technology, specifically to a method and apparatus for voltage flicker suppression in new energy grid-connected systems. Background Technology

[0002] In renewable energy grid-connected systems, the volatility of renewable energy generation is a key factor causing voltage flicker. For example, in wind power generation, the random variation in wind speed leads to low-frequency fluctuations in output power, especially under conditions of gusts and turbulence, where output power fluctuates significantly within specific frequency bands. In photovoltaic power generation, the influence of changes in sunlight intensity, such as cloud cover and weather variations, results in high-frequency and non-periodic fluctuations in output power. Therefore, during renewable energy generation, these power fluctuations are further transmitted through grid impedance, causing rapid and periodic changes in grid voltage amplitude, resulting in voltage flicker. Voltage flicker reduces the stability of equipment, such as causing flickering lights in lighting equipment and image distortion in electronic devices, affecting the synchronous stability of the grid. Therefore, suppressing voltage flicker in renewable energy grid-connected systems is a crucial step in ensuring power quality and normal equipment operation.

[0003] However, in addressing voltage flicker suppression in grid-connected renewable energy systems, the power fluctuations of renewable energy sources such as wind and solar power vary significantly. Traditional suppression methods respond slowly to power changes in these systems, failing to track and compensate for rapidly changing power fluctuations, resulting in poor voltage flicker suppression. Consequently, in complex grid environments where multiple renewable energy power plants are connected to the grid, the differences in interference fluctuations between different types of energy sources during actual grid connection are not fully considered. This leads to significant deviations in voltage flicker suppression using traditional dynamic compensation techniques, causing power fluctuations after renewable energy grid connection to overlap, and the impact of grid voltage flicker remains severe. Summary of the Invention

[0004] To address the aforementioned technical problems, this application provides a method and apparatus for suppressing voltage flicker in a new energy grid-connected system. The specific technical solution adopted is as follows:

[0005] In a first aspect, one embodiment of this application provides a voltage flicker suppression device for a new energy grid-connected system, the device comprising:

[0006] The signal acquisition and preprocessing unit is used to acquire and preprocess the voltage, current and power data of the common connection point of the new energy power station and the new energy power generation equipment in real time.

[0007] The feature analysis unit, connected to the signal acquisition and preprocessing unit, is used to divide each type of preprocessed data into several sub-band components according to frequency band, and calculate the short-time flicker value Pst and peak point distribution characteristics of each sub-band component in the frequency domain.

[0008] A response time adjustment unit, connected to the feature analysis unit, is used to generate response time adjustment coefficients for corresponding sub-band components based on the Pst value and the peak point distribution characteristics, so as to adjust the initial response time of different frequency bands.

[0009] The compensation calculation unit is connected to the response time adjustment unit and is used to determine the response time in the dynamic power compensation device based on the adjusted response time, so as to suppress the voltage flicker of the new energy grid-connected system through the dynamic power compensation device.

[0010] The response time adjustment unit includes:

[0011] The first calculation module is used to generate characteristic values ​​of voltage flicker caused by interference fluctuations in the corresponding frequency band of the sub-band component based on the similarity characteristics between the peak point distribution characteristics of the sub-band components in the frequency domain and the differences between the Pst values ​​of multiple data in the same frequency band.

[0012] The second calculation module is used to generate adjustment coefficients for the dominant interference influence in the corresponding frequency band of the sub-band component based on the eigenvalue and Pst value.

[0013] The third calculation module is used to perform weighted correction on the initial response time using the adjustment coefficient to obtain the adjusted response time for different frequency bands.

[0014] The generation relationship of the characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band of the sub-band component is as follows:

[0015]

[0016] in, Indicates the first The first type of power grid parameter data Each sub-band component corresponds to a characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band; m represents the type of power grid parameter; Indicates the first The first type of power grid parameter data Pst values ​​of the spectral data of each sub-band component; Indicates the first The first type of power grid parameter data Pst values ​​of the spectral data of each sub-band component; Indicates the first species and first The first type of power grid parameter data Pearson correlation coefficient between the characteristic curves of each sub-band component This indicates a constant that is intended to avoid a denominator of 0;

[0017] The formula for generating the adjustment coefficient of the dominant interference effect in the corresponding frequency band of the sub-band component is as follows:

[0018]

[0019] in, Indicates the first The first type of power grid parameter data The adjustment coefficient of the dominant interference effect of each sub-band component in the corresponding frequency band; Indicates the first The first type of power grid parameter data The short-time flicker value of each sub-band component in the corresponding frequency band is the proportion of the short-time flicker value and the total short-time flicker value in all frequency bands. and They represent the first The first type of power grid parameter data The and the first The Pst value corresponding to each sub-band component; and They represent the first The first type of power grid parameter data The and the first The characteristic value of voltage flicker caused by interference fluctuations in the frequency band corresponding to each sub-band component.

[0020] Preferably, the feature analysis unit includes:

[0021] A bandpass filter bank is used to divide the preprocessed data into n sub-band components, where n is an integer from 3 to 7;

[0022] The peak point distribution characteristic analysis submodule is used to calculate the peak point distribution characteristics of each sub-band component in the frequency domain;

[0023] The flicker evaluation submodule is used to calculate the Pst value of each subband component in the frequency domain.

[0024] Preferably, the formula for obtaining the response time after adjustment for different frequency bands is:

[0025]

[0026] in For the first Response time after frequency band adjustment; For the first Initial response time of each frequency band; This indicates the preset threshold for adjusting the response time; Indicates the first The normalized result of the adjustment coefficients corresponding to each frequency band.

[0027] Preferably, before the response time adjustment unit, the device further includes a frequency band adjustment sequence determination unit, which is connected to the response time adjustment unit and is used to determine the order of frequency band response time adjustment by utilizing the energy proportion of sub-band components before the initial response time adjustment of different frequency bands.

[0028] Preferably, the device further includes a feedback monitoring unit connected to the compensation calculation unit, used to perform real-time Pst qualification value analysis on the compensated power grid parameters.

[0029] Preferably, the device further includes a control decision unit connected to the feedback monitoring unit, used to feed back the Pst qualified value analysis results to the control decision unit to form a closed-loop regulation mechanism for voltage flicker suppression in the grid-connected system.

[0030] Secondly, another embodiment of this application provides a voltage flicker suppression method for a new energy grid-connected system, wherein the method sequentially implements the execution contents of each unit in the voltage flicker suppression device for a new energy grid-connected system described above.

[0031] This application has at least the following beneficial effects:

[0032] This application employs a dynamic power compensation device to suppress voltage flicker in a new energy grid-connected system. During the processing, grid parameters are collected in real time. By analyzing the frequency synchronization characteristics of the collected grid parameters across different frequency bands and the interference fluctuation characteristics that cause voltage flicker, the response time for different frequency bands in the actual processing is dynamically adjusted and determined. The beneficial effect is that it fully considers the interference fluctuation characteristics of the grid parameters output from the generator end at different time periods, precisely adjusts the response time during the dynamic power compensation process, and thus efficiently suppresses voltage flicker in the grid-connected system, improving grid voltage quality. Attached Figure Description

[0033] Figure 1 This is a unit structure diagram of a voltage flicker suppression device for a new energy grid-connected system, provided as an embodiment of this application. Detailed Implementation

[0034] Example 1

[0035] As attached Figure 1As shown in the unit structure diagram, this application proposes a voltage flicker suppression device for a new energy grid-connected system, which is used to suppress voltage flicker in the power grid through a dynamic power compensation device. The voltage flicker suppression device for a new energy grid-connected system consists of a signal acquisition and preprocessing unit, a feature analysis unit, a response time adjustment unit, a compensation amount calculation unit, a frequency band adjustment sequence determination unit, a feedback monitoring unit, and a control decision unit.

[0036] The specific uses of each unit are detailed below:

[0037] The signal acquisition and preprocessing unit is used to acquire and preprocess the voltage, current and power data of the common connection point of the new energy power station and the new energy power generation equipment in real time.

[0038] The feature analysis unit, connected to the signal acquisition and preprocessing unit, is used to divide each type of preprocessed data into several sub-band components according to frequency band, and calculate the short-time flicker value Pst and peak point distribution characteristics of each sub-band component in the frequency domain.

[0039] A response time adjustment unit, connected to the feature analysis unit, is used to generate response time adjustment coefficients for corresponding sub-band components based on the Pst value and the peak point distribution characteristics, so as to adjust the initial response time of different frequency bands.

[0040] The compensation calculation unit is connected to the response time adjustment unit and is used to determine the response time in the dynamic power compensation device based on the adjusted response time, so as to suppress the voltage flicker of the new energy grid-connected system through the dynamic power compensation device.

[0041] The frequency band adjustment sequence determination unit, connected to the response time adjustment unit, is used to determine the order of frequency band response time adjustment by utilizing the energy proportion of sub-band components before the initial response time adjustment of different frequency bands.

[0042] The feedback monitoring unit is connected to the compensation calculation unit and is used to perform real-time Pst qualification value analysis on the compensated power grid parameters.

[0043] The control decision unit, connected to the feedback monitoring unit, is used to feed back the Pst qualified value analysis results to the control decision unit to form a closed-loop regulation mechanism for voltage flicker suppression in the grid-connected system.

[0044] The feature analysis unit includes:

[0045] A bandpass filter bank is used to divide the preprocessed data into n sub-band components, where n is an integer from 3 to 7;

[0046] The peak point distribution characteristic analysis submodule is used to calculate the peak point distribution characteristics of each sub-band component in the frequency domain;

[0047] The flicker evaluation submodule is used to calculate the Pst value of each subband component in the frequency domain.

[0048] The response time adjustment unit includes:

[0049] The first calculation module is used to generate characteristic values ​​of voltage flicker caused by interference fluctuations in the corresponding frequency band of the sub-band component based on the similarity characteristics between the peak point distribution characteristics of the sub-band components in the frequency domain and the differences between the Pst values ​​of multiple data in the same frequency band.

[0050] The second calculation module is used to generate adjustment coefficients for the dominant interference influence in the corresponding frequency band of the sub-band component based on the eigenvalue and Pst value.

[0051] The third calculation module is used to perform weighted correction on the initial response time using the adjustment coefficient to obtain the adjusted response time for different frequency bands.

[0052] Example 2

[0053] Accordingly, based on the same inventive concept as the voltage flicker suppression device for a new energy grid-connected system described above, this embodiment provides a voltage flicker suppression method for a new energy grid-connected system. This method sequentially implements the execution contents within each unit of the voltage flicker suppression device for a new energy grid-connected system described above. The specific execution contents are detailed below:

[0054] S1 signal acquisition and processing is the execution content of the signal acquisition and preprocessing unit.

[0055] Firstly, in the process of voltage flicker suppression for new energy grid-connected systems, a signal acquisition and preprocessing unit in a voltage flicker suppression device for new energy grid-connected systems is used to collect grid parameters in real time from the common connection point of the new energy power plant and the output port of the new energy power generation equipment. The grid parameters include voltage data, current data, and power data. In order to accurately capture the fluctuation characteristics of the relevant parameters that cause voltage flicker, the grid parameters are sampled at a frequency of 1000 data points per second in this embodiment.

[0056] Because the actual data acquisition process may be affected by equipment and environmental noise interference, resulting in poor data quality, this paper uses the acquired power grid parameter data as input and employs a wavelet denoising algorithm to filter and reduce noise, thereby avoiding the influence of high-frequency noise and other interference signals on the analysis of power grid parameter fluctuation characteristics during new energy grid integration. A normalization method is then used to normalize the filtered and denoised data to avoid the impact of dimensional differences on the analysis of power grid parameter variation characteristics. Further data cleaning methods, such as anomaly detection and missing value imputation, are used to further process the normalized data, improving the quality of the acquired power grid parameter data.

[0057] The characteristic analysis of power grid parameters in the S2 grid-connected system is the content executed in the characteristic analysis unit.

[0058] By collecting grid parameter data during the grid connection process of new energy sources, the relevant parameters during the grid connection process of new energy sources are monitored and analyzed in real time. This allows for precise analysis and feedback of the fluctuation characteristics of grid parameters, and effective suppression of voltage flicker in the new energy grid connection system.

[0059] Normally, when renewable energy is connected to the grid, if the power generation is stable, the voltage, current, and power change synchronously, and the possibility of voltage flicker after connection is small. However, renewable energy generation is mainly based on wind power and photovoltaic power generation. Due to the influence of environmental changes, the grid parameters may fluctuate during the process of renewable energy being connected to the grid. Furthermore, the different types of power generation equipment and the different interference effects at different times result in significant differences in the fluctuation of grid parameters during the process of renewable energy grid connection, which in turn affects the effectiveness of voltage flicker suppression for grid fluctuations.

[0060] Therefore, based on the grid parameters collected in real time at the common connection point of the new energy power plant and the output port of the new energy power generation equipment, the grid fluctuation characteristics during the operation of the new energy grid-connected system are dynamically analyzed. By fully considering the differences in grid parameter changes for different power generation types and at different stages, the parameter fluctuation characteristics causing voltage flicker during the new energy connection process are accurately analyzed, thereby effectively suppressing voltage flicker in the new energy grid-connected system. The specific analysis and processing process is as follows:

[0061] Firstly, when targeting new energy grid-connected systems, dynamic power compensation devices are used to suppress voltage flicker during grid connection. However, in actual use, due to the complexity of the grid environment, the diversity of new energy power generation equipment, and the differences in the environmental changes they need to cope with, the processing effect of grid parameters during the voltage flicker suppression process is poor, affecting the voltage flicker suppression effect.

[0062] Therefore, for each type of power grid parameter collected, all preprocessed data acquired up to the current time are used as input, and a variational mode decomposition algorithm is employed to obtain the frequency band-based data for each type of power grid parameter. The number of sub-band components, specifically in one embodiment of this application, is [number]. .

[0063] Furthermore, due to the intermittent and random interference characteristics in the process of new energy power generation, the grid parameters fluctuate and vary in different frequency bands. In order to accurately analyze the variation characteristics of the grid parameters in different frequency bands under the above interference characteristics, Fourier transform is used to obtain the spectrum data of each sub-band component.

[0064] Furthermore, the obtained spectral data of each sub-band component is used as input, and the findpeaks function in MATLAB is used to detect peaks and obtain the peaks and their corresponding frequencies in the spectral data of the sub-band components.

[0065] Because the grid parameters at the power generation end are affected by environmental interference during the actual processing, the fluctuations of these grid parameters vary significantly across different frequency bands, thus affecting the stability of the grid connection. Therefore, based on the real-time collected grid parameters in the grid connection system, the interference fluctuation response characteristics under different frequency bands are analyzed, and then the parameter changes caused by voltage flicker in the new energy grid connection system are compensated and adjusted to suppress voltage flicker.

[0066] Specifically, considering the characteristic of frequency synchronous response changes in grid parameters across different frequency bands in new energy grid-connected systems, and the small fluctuations and non-periodic variations in grid parameters across different frequency bands under intermittent and random disturbances at the generation end.

[0067] Therefore, for the spectral data of each sub-band component of each type of grid parameter data, all peak values ​​and their corresponding frequencies are mapped to a rectangular coordinate system with frequency as the horizontal axis and peak value as the vertical axis. The corresponding fitting curve is obtained using the least squares method. The fitting curve is a characteristic curve of the amplitude response change of the grid parameters in different frequency bands in the grid-connected system. During operation, if interference fluctuations occur, the correlation between the amplitude responses of the grid parameters in different frequency bands will decrease. Furthermore, the degree of voltage flicker caused by the characteristics of interference fluctuations in different frequency bands in the grid-connected system is different. Therefore, the Pst value (short-time flicker value) of the spectral data of each sub-band component is calculated. The larger the Pst value, the higher the sensitivity of the voltage flicker caused by the data change in the current frequency band.

[0068] The response time adjustment of S3 power grid parameter data under different frequency bands is the execution content of the response time adjustment unit.

[0069] (1) This application combines the characteristics of synchronous response changes between different frequency bands of power grid parameters and the sensitivity characteristics of voltage flicker caused by different frequency bands, and comprehensively analyzes the characteristic values ​​of voltage flicker caused by interference fluctuations of power grid parameters in different frequency bands. The calculation relationship is as follows:

[0070]

[0071] in, Indicates the first The first type of power grid parameter data Each sub-band component corresponds to a characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band; m represents the type of power grid parameter; Indicates the first The first type of power grid parameter data Pst values ​​of the spectral data of each sub-band component; Indicates the first The first type of power grid parameter data The Pst values ​​of the spectral data of each sub-band component, where The larger the calculation result, the more significant the sensitivity of voltage flicker caused by the parameter interference fluctuation characteristics of other grid parameters in the same frequency band compared with the current grid parameters. The higher the accuracy of the correlation characteristics between the corresponding similar frequency bands for voltage flicker characteristic analysis. Indicates the first species and first The first type of power grid parameter data Pearson correlation coefficient between the characteristic curves of each sub-band component The larger the value, the greater the frequency difference in power grid parameters caused by interference in similar frequency bands, which may lead to asynchronous response changes in power grid parameters. This represents a default constant to avoid denominators of 0, with a value of 0.01, to prevent denominators from being zero.

[0072] The above analysis of the correlation characteristics of parameter interference fluctuations among grid parameters in similar frequency bands and the sensitivity characteristics that cause voltage flicker phenomena yielded characteristic values ​​of voltage flicker caused by interference fluctuations among grid parameters in different frequency bands. The larger the characteristic value, the greater the likelihood that interference fluctuations among grid parameters in the current frequency band during grid connection will cause flicker phenomena, as it integrates the frequency band synchronization characteristics and the sensitivity characteristics that cause flicker phenomena among grid parameters in the grid-connected system.

[0073] (2) Based on the above analysis, in the new energy grid connection system, compared with the traditional dynamic power compensation process for the analysis of grid parameter fluctuation characteristics, this application is based on the difference in the actual grid connection type and the difference in the interference influence characteristics of grid parameters under different time periods. According to the frequency synchronization characteristics of grid parameters in different frequency bands and the sensitivity characteristics that cause voltage flicker, the interference fluctuation characteristics of grid parameters under different conditions are accurately analyzed, thereby effectively extracting the grid parameter characteristics in the grid connection system.

[0074] Furthermore, in order to accurately reflect the impact of changes in grid parameters on voltage flicker in the new energy grid-connected system, and thus to more accurately suppress voltage flicker during the dynamic power compensation process, this application analyzes the interference fluctuations caused by short-term flicker phenomena due to real-time grid parameters collected in the grid-connected system, and dynamically adjusts the response time during the dynamic power compensation process based on the analysis results.

[0075] Specifically, for each grid parameter, the adjustment coefficient of the dominant disturbance influence in the dynamic power compensation process of the grid parameter in different frequency bands is calculated by comparing the proportion of short-time flicker characteristics in different frequency bands to the overall short-time flicker characteristics. The calculation formula is as follows:

[0076]

[0077] in, Indicates the first The first type of power grid parameter data The adjustment coefficient of the dominant interference effect of each sub-band component in the corresponding frequency band; Indicates the first The first type of power grid parameter data The short-time flicker value of each sub-band component in the corresponding frequency band is the proportion of the short-time flicker value and the total short-time flicker value in all frequency bands. and They represent the first The first type of power grid parameter data The and the first The Pst value corresponding to each sub-band component; and They represent the first The first type of power grid parameter data The and the first The characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band of each sub-band component; the larger the calculated adjustment coefficient, the more significant the interference influence characteristics of the change of the grid parameters in different frequency bands, and the comprehensive proportion of short-time flicker characteristics compared with the flicker characteristics and interference influence characteristics of all frequency bands. The corresponding frequency band is more significantly affected by the change of the dominant frequency causing voltage flicker. The initial response time needs to be dynamically adjusted accordingly to respond in a timely manner to suppress the voltage flicker phenomenon caused by the fluctuation of grid parameters.

[0078] (3) Furthermore, in this application, the response time is dynamically adjusted by the adjustment coefficient of the dominant interference influence in the dynamic power compensation process of the grid parameters in different frequency bands; specifically, all the adjustment coefficients are used as inputs, and the normalization processing method is used to obtain the normalization processing results of all the adjustment coefficients. In order to accurately judge the degree of interference influence of different frequency bands compared with the overall frequency range, this embodiment uses the mean of all the normalization processing results as the judgment threshold for response time adjustment. Specifically, the response time for adjusting the renewable energy grid-connected system using a dynamic power compensation device is: ;in For the first Response time after frequency band adjustment; For the first The initial response time of each frequency band; where, for the initial response time of each frequency band for each type of power grid parameter, the center frequency is first determined according to the frequency range of the sub-band component corresponding to each frequency band, and the initial response time is determined based on the center frequency, that is, the reciprocal of the center frequency is the magnitude of the initial response time. This indicates the preset threshold for adjusting the response time; Indicates the first The normalized result of the adjustment coefficient corresponding to each frequency band, that is, the more significant the dominant interference influence of the current frequency band compared to the overall frequency band range, the smaller the corresponding response time, and the more the voltage flicker caused by interference fluctuations is suppressed.

[0079] S4 uses the energy of the frequency band components to determine the priority order of the matching response time, and determines the execution content in the frequency band adjustment sequence determination unit.

[0080] Based on the above processing results, the priority of response time matching is further determined by combining the energy proportion of different bands.

[0081] The process involves calculating the energy of each sub-band component in the corresponding frequency band, where the energy is the product of the sum of squares of all amplitudes in the corresponding sub-band component and the bandwidth; calculating the proportion of the energy of each sub-band component in the corresponding frequency band to the total energy in all frequency bands; and determining the order of matching response times based on the proportion from largest to smallest, i.e., the larger the proportion and the higher the energy, the higher the priority for matching response times.

[0082] S5 evaluates the compensated grid parameters, which is the execution content in the feedback monitoring unit.

[0083] The feedback monitoring unit analyzes the compensated power grid parameters in real time, such as whether the Pst value of each frequency band has dropped to the qualified value, where the qualified value is less than 1.0.

[0084] S6 uses the evaluation results to control the dynamic power compensation device, which is the execution content in the control decision unit.

[0085] The evaluation results of the feedback monitoring unit are fed back to the control decision unit to control the dynamic power compensation device, thereby forming a closed-loop regulation mechanism for voltage flicker suppression in the grid-connected system.

[0086] This application sets up a voltage flicker suppression device to achieve precise dynamic suppression of voltage flicker in the new energy grid-connected system through a dynamic power compensation device, thereby ensuring that the grid voltage quality meets the standard requirements.

[0087] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the invention herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not invented in this application.

[0088] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope.

Claims

1. A voltage flicker suppression device for a new energy grid-connected system, characterized in that, The device includes: The signal acquisition and preprocessing unit is used to acquire and preprocess the voltage, current and power data of the common connection point of the new energy power station and the new energy power generation equipment in real time. The feature analysis unit, connected to the signal acquisition and preprocessing unit, is used to divide each type of preprocessed data into several sub-band components according to frequency band, and calculate the short-time flicker value Pst and peak point distribution characteristics of each sub-band component in the frequency domain. A response time adjustment unit, connected to the feature analysis unit, is used to generate response time adjustment coefficients for corresponding sub-band components based on the Pst value and the peak point distribution characteristics, so as to adjust the initial response time of different frequency bands. The compensation calculation unit is connected to the response time adjustment unit and is used to determine the response time in the dynamic power compensation device based on the adjusted response time, so as to suppress the voltage flicker of the new energy grid-connected system through the dynamic power compensation device. The response time adjustment unit includes: The first calculation module is used to generate characteristic values ​​of voltage flicker caused by interference fluctuations in the corresponding frequency band of the sub-band component based on the similarity characteristics between the peak point distribution characteristics of the sub-band components in the frequency domain and the differences between the Pst values ​​of multiple data in the same frequency band. The second calculation module is used to generate adjustment coefficients for the dominant interference influence in the corresponding frequency band of the sub-band component based on the characteristic value and the Pst value. The third calculation module is used to perform weighted correction on the initial response time using the adjustment coefficient to obtain the adjusted response time for different frequency bands. The generation relationship of the characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band of the sub-band component is as follows: ,in, Indicates the first The first type of power grid parameter data Each sub-band component corresponds to a characteristic value of voltage flicker caused by interference fluctuations in the corresponding frequency band; m represents the type of power grid parameter; Indicates the first The first type of power grid parameter data Pst values ​​of the spectral data of each sub-band component; Indicates the first The first type of power grid parameter data Pst values ​​of the spectral data of each sub-band component; Indicates the first species and first The first type of power grid parameter data Pearson correlation coefficient between the characteristic curves of each sub-band component This indicates a constant that is intended to avoid a denominator of 0; The formula for generating the adjustment coefficient of the dominant interference effect in the corresponding frequency band of the sub-band component is as follows: ,in, Indicates the first The first type of power grid parameter data The adjustment coefficient of the dominant interference effect of each sub-band component in the corresponding frequency band; Indicates the first The first type of power grid parameter data The short-time flicker value of each sub-band component in the corresponding frequency band is at the... The short-time flicker values ​​and their proportions in the frequency bands of all sub-band components of the power grid parameter data; and They represent the first The first type of power grid parameter data The and the first The Pst value corresponding to each sub-band component; and They represent the first The first type of power grid parameter data The and the first The characteristic value of voltage flicker caused by interference fluctuations in the frequency band corresponding to each sub-band component.

2. The voltage flicker suppression device for a new energy grid-connected system according to claim 1, characterized in that, The feature analysis unit includes: A bandpass filter bank is used to divide the preprocessed data into n sub-band components, where n is an integer from 3 to 7; The peak point distribution characteristic analysis submodule is used to calculate the peak point distribution characteristics of each sub-band component in the frequency domain; The flicker evaluation submodule is used to calculate the Pst value of each subband component in the frequency domain.

3. The voltage flicker suppression device for a new energy grid-connected system according to claim 1, characterized in that, The formula for obtaining the response time after adjustment for different frequency bands is as follows: ,in For the first Response time after frequency band adjustment; For the first Initial response time of each frequency band; This indicates the preset threshold for adjusting the response time; Indicates the first The normalized result of the adjustment coefficients corresponding to each frequency band.

4. The voltage flicker suppression device for a new energy grid-connected system according to claim 1, characterized in that, Before the response time adjustment unit, the device also includes a frequency band adjustment sequence determination unit, which is connected to the response time adjustment unit and is used to determine the order of frequency band response time adjustment by using the energy proportion of sub-band components before the initial response time adjustment of different frequency bands.

5. A voltage flicker suppression device for a new energy grid-connected system according to claim 1, characterized in that, The device also includes a feedback monitoring unit, which is connected to the compensation calculation unit, for real-time analysis of the Pst qualified value of the compensated power grid parameters.

6. A voltage flicker suppression device for a new energy grid-connected system according to claim 1, characterized in that, The device also includes a control decision unit connected to the feedback monitoring unit, which feeds back the Pst qualified value analysis results to the control decision unit to control the dynamic power compensation device and form a closed-loop regulation mechanism for voltage flicker suppression in the grid-connected system.

7. A method for suppressing voltage flicker in a new energy grid-connected system, characterized in that, The method sequentially executes the functions within each unit of the voltage flicker suppression device for a new energy grid-connected system as described in any one of claims 1-6.

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