A new energy cluster power regulation optimization decision-making method

Abstract

This invention discloses a power regulation optimization decision-making method for new energy clusters, relating to the field of power regulation technology. It addresses the problem of power regulation response lagging behind the actual disturbance evolution process due to the inability to predict the affected areas of power plants in advance. The method collects active power data from each grid-connected point of a new energy base by setting a sliding time window, identifies the transit state of the fluctuation front using zero-lag cross-analysis, and filters covered power plants. It calculates the duration of the fluctuation by combining the power generation capacity, reserve capacity ratio, and disturbance absorption capacity of each power plant, and calculates the residual energy index. Based on the power regulation target value, the method completes task decomposition. Simultaneously, it corrects the regulation results by combining the negative sequence component amplitude of each grid-connected point, generates differentiated regulation commands, and collects voltage harmonic distortion data after execution. It assesses the direction of the power impact and supplements and corrects the regulation commands, achieving forward-looking power redistribution of new energy base clusters under local micro-meteorological disturbances and improving dispatch response speed.

Description

Technical Field

[0001] This invention relates to the field of power regulation technology, and more specifically, to a power regulation optimization decision-making method for a new energy group. Background Technology

[0002] As the installed capacity of new energy continues to expand, new energy bases are usually composed of multiple new energy power stations such as wind farms and photovoltaic power stations. Each power station outputs power to the grid through a unified grid connection node. During the operation of new energy bases, affected by factors such as local weather changes, cloud movement, and sudden changes in wind speed, the output status of new energy power stations in different regions will exhibit rapid fluctuations with spatial propagation characteristics, making the overall power output of new energy bases show obvious time-varying and asynchronous characteristics.

[0003] The existing technology has the following shortcomings: Currently, existing power regulation methods for new energy clusters typically rely on passive adjustments based on the overall power deviation of the new energy base or the current output changes of each station. This lacks the ability to dynamically identify the propagation process of power fluctuations at different stations and the range of disturbance impacts. Consequently, it is impossible to determine the station areas affected by fluctuations in advance, causing the power regulation response to lag behind the actual disturbance evolution process. This reduces the speed and coordination of the overall power regulation of the new energy cluster. Therefore, an optimized decision-making method for power regulation of new energy clusters is proposed.

[0004] The information disclosed in the background section is only intended to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0005] To overcome the aforementioned deficiencies in the prior art, embodiments of the present invention provide a new energy cluster power regulation optimization decision-making method. This method addresses the problems mentioned in the background art by employing a new energy cluster power fluctuation front identification method based on a sliding time window, a power regulation task dynamic decomposition method combining disturbance absorption capacity and residual energy state, and a regulation command closed-loop correction method based on power impact feedback.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a new energy cluster power regulation optimization decision-making method, comprising the following steps: Step S1: Set a sliding time window, read the active power data of each grid-connected point in the new energy base within the sliding time window, perform zero-lag cross-analysis based on the active power data, and determine the wave front transit status of each station based on the results of the zero-lag cross-analysis. Step S2: Based on the transit status of the wave front, screen and identify the stations covered by the wave front, collect the adjustable capacity of the stations covered by the wave front and analyze the disturbance absorption capacity, and use the disturbance absorption capacity to calculate the duration of the wave. Step S3: Calculate the residual energy index based on the duration of the fluctuation, read the power regulation target value of the new energy base, decompose the power regulation target value based on the residual energy index, detect the negative sequence component amplitude of the grid connection point of each fluctuation front covered by the power station, and generate the power regulation command of each fluctuation front covered by the power station based on the decomposition results. Step S4: After issuing and executing the power regulation command, collect the voltage harmonic distortion data of each power station grid connection point covered by the wave front and assess the direction of the power impact. Based on the direction of the power impact, determine whether to supplement and correct the power regulation command.

[0007] In a preferred embodiment, in step S1, a sliding time window is set. The sliding time window refers to a data analysis interval constructed according to a fixed time length. Whenever a sampling cycle is completed, the sliding time window slides forward by one sampling interval. Within the sliding time window, the active power data corresponding to each grid connection point is collected by the synchronous phasor measurement device configured at each grid connection point. The active power data refers to the instantaneous active power measurement value actually output by each grid connection point to the public power grid. Calculate the rate of change of active power between adjacent sampling times at each station; When the absolute value of the active power change rate corresponding to the sampling time is greater than or equal to the power change rate trigger threshold, the corresponding sampling time will be recorded as the disturbance trigger time of the corresponding station. The station with the earliest disturbance trigger time is selected as the reference station, and the active power data corresponding to the reference station is extracted as the reference sequence. All other stations are used as target stations.

[0008] In a preferred embodiment, in step S1, the average active power data of the reference sequence and the target station are calculated within the current sliding time window to obtain the average active power. The power offset of the reference station and the target station is obtained by removing the mean from the average active power at each sampling time. Based on the power offset, the Pearson correlation coefficient between the active power data of the target station and the reference sequence under zero time shift condition is calculated one by one to obtain the zero-hysteresis cross coefficient. When the zero-hysteresis cross coefficient corresponding to the target power station is higher than the preset relevant judgment threshold, and the direction of the active power change rate corresponding to the target power station is consistent with the direction of the active power change rate corresponding to the benchmark power station, it is determined that the target power station has entered the state of wave front transit. Otherwise, it is determined that the target station has not yet entered the state of the transit of the fluctuating front.

[0009] In a preferred embodiment, in step S2, the stations that have entered the state of wave front passage are identified as wave front covered stations, the current upward reserve capacity and the current downward reserve capacity of each wave front covered station are read, and the smaller value between the current upward reserve capacity and the current downward reserve capacity is taken as the current adjustable capacity. Divide the current adjustable capacity by the average active power, and then multiply by the length of the sliding time window to calculate the disturbance absorption capacity of each station covered by the wave front. Read the active power change rate corresponding to the end of the current sliding time window of each wave front-covered station, and calculate the wave duration corresponding to each wave front-covered station in combination with the disturbance absorption capacity.

[0010] In a preferred embodiment, in step S3, the average duration of fluctuations across all stations covered by the fluctuation front is calculated; The residual energy index is calculated by combining the average duration of fluctuations and the duration of fluctuations corresponding to the stations covered by each fluctuation front. Read the power adjustment target value of the new energy base within the current scheduling cycle. The power adjustment target value represents the amount of active power adjustment that the new energy base as a whole needs to perform. The dynamic rapid adjustment ratio is calculated based on the residual energy index, and the basic slow adjustment ratio is calculated based on the dynamic rapid adjustment ratio. The dynamic fast-change regulation ratio and the basic slow-change regulation ratio are calculated by multiplying them by the power regulation target value.

[0011] In a preferred embodiment, in step S3, the negative sequence component amplitude of each power station grid connection point covered by the wave front is detected. The negative sequence component amplitude is obtained by the synchronous phasor measurement device set at each power station grid connection point, which collects the three-phase voltage phasors and then calculates them through symmetrical component transformation. The current negative sequence component amplitude is compared with the average value of the negative sequence components under historical stable operating conditions to calculate the negative sequence offset rate. Generate negative order correction coefficients based on negative order offset rate; The negative sequence correction coefficient is introduced into the current adjustable capacity to obtain the corrected adjustable carrying capacity. The dynamic fast-change adjustment allocation ratio is then calculated based on the corrected adjustable carrying capacity.

[0012] In a preferred embodiment, in step S3, the dynamic rapid change adjustment amount is allocated according to the dynamic rapid change adjustment amount allocation ratio to obtain the actual dynamic rapid change adjustment amount undertaken. The base slow-varying regulation amount is allocated using the current adjustable capacity to obtain the actual base slow-varying regulation amount undertaken. The actual dynamic fast-change regulation amount undertaken is superimposed with the actual basic slow-change regulation amount undertaken to generate the power regulation command for the power station covered by the fluctuation front.

[0013] In a preferred embodiment, in step S4, the power adjustment command of each wave front covering the station is sent to the station-side converter control unit to perform the power adjustment action; After the power regulation command is issued, the three-phase voltage waveform at the grid connection point is acquired according to the preset sampling period and a fast Fourier transform is performed to obtain the amplitude of each harmonic voltage. The voltage harmonic distortion rate of each wave front-covered power station grid connection point is calculated based on the voltage components of each harmonic. At the same time, the current harmonic data corresponding to each power station grid connection point is collected and the current harmonic distortion rate is calculated. The voltage harmonic distortion rate is divided by the current harmonic distortion rate to obtain the power impact evaluation quantity. Read the power impact evaluation quantity within the preset time window before the power adjustment command is executed, and calculate the baseline value before execution.

[0014] In a preferred embodiment, in step S4, after the adjustment command is executed, the energy impact evaluation quantity after execution is read, and the adjustment impact change rate is calculated in combination with the baseline value before execution. When the rate of change of the regulation impact is greater than 0, it is determined that the direction of the enhanced power impact generated by the current regulation action of the wave front covering the station is determined, and the corresponding regulation command is supplemented and corrected at this time. When the rate of change of the regulating impact is less than or equal to 0, the direction of the suppressive electrical energy impact generated by the current regulating action of the wave front covering the station is determined, and the current regulating command is kept in execution. When supplementing and correcting the power regulation command of the power station covered by the wave front that generates the enhanced power impact direction, the supplementary and corrected power command is generated according to the rate of change of the impact. The power adjustment command is superimposed with the supplementary power correction command to obtain the final compensated power adjustment command.

[0015] The technical effects and advantages of this invention are as follows: This invention continuously collects active power data from each grid-connected station in a new energy base by setting a sliding time window. It then identifies the transit status of a wave front based on zero-lag cross-analysis, selects stations covered by the wave front, and calculates the duration of the wave based on the station's current generating capacity, reserve capacity ratio, and disturbance absorption capacity. Further, it calculates the residual energy index based on the wave duration and decomposes the regulation task according to the power regulation target value of the new energy base. Simultaneously, it introduces the negative sequence component amplitude of each grid-connected station to correct the regulation results, generating differentiated regulation commands. Finally, after the regulation commands are executed, it collects voltage harmonic distortion data from each station, assesses the direction of the electrical energy impact generated during the regulation process, and supplements and corrects the regulation commands based on the assessment results, forming a closed-loop regulation decision-making system. This enables proactive power redistribution of the new energy base cluster under local micro-meteorological disturbance conditions, improving dispatch response speed. Attached Figure Description

[0016] Figure 1 This is a flowchart illustrating the implementation of a new energy cluster power regulation optimization decision-making method according to the present invention.

[0017] Figure 2 This is a schematic diagram illustrating the steps of a new energy cluster power regulation optimization decision-making method according to the present invention. Detailed Implementation

[0018] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0019] This invention continuously collects active power data from each grid-connected station in a new energy base by setting a sliding time window. It then identifies the transit status of a wave front based on zero-lag cross-analysis, selects stations covered by the wave front, and calculates the duration of the wave based on the station's current generating capacity, reserve capacity ratio, and disturbance absorption capacity. Further, it calculates the residual energy index based on the wave duration and decomposes the regulation task according to the power regulation target value of the new energy base. Simultaneously, it introduces the negative sequence component amplitude of each grid-connected station to correct the regulation results, generating differentiated regulation commands. Finally, after the regulation commands are executed, it collects voltage harmonic distortion data from each station, assesses the direction of the electrical energy impact generated during the regulation process, and supplements and corrects the regulation commands based on the assessment results, forming a closed-loop regulation decision-making system. This enables forward-looking power redistribution of the new energy base cluster under local micro-meteorological disturbance conditions.

[0020] Example 1, such as Figures 1 to 2 As shown, a new energy cluster power regulation optimization decision-making method includes the following steps: Step S1: Set a sliding time window, read the active power data of each grid-connected point in the new energy base within the sliding time window, perform zero-lag cross-analysis based on the active power data, and determine the wave front transit status of each station based on the results of the zero-lag cross-analysis. Step S2: Based on the transit status of the wave front, screen and identify the stations covered by the wave front, collect the adjustable capacity of the stations covered by the wave front and analyze the disturbance absorption capacity, and use the disturbance absorption capacity to calculate the duration of the wave. Step S3: Calculate the residual energy index based on the duration of the fluctuation, read the power regulation target value of the new energy base, decompose the power regulation target value based on the residual energy index, detect the negative sequence component amplitude of the grid connection point of each fluctuation front covered by the power station, and generate the power regulation command of each fluctuation front covered by the power station based on the decomposition results. Step S4: After issuing and executing the power regulation command, collect the voltage harmonic distortion data of each power station grid connection point covered by the wave front and assess the direction of the power impact. Based on the direction of the power impact, determine whether to supplement and correct the power regulation command.

[0021] The specific implementation is as follows: In step S1, a sliding time window is first set, and the active power data of each grid-connected station in the new energy base are continuously read according to a preset sampling period. The sliding time window refers to a data analysis interval constructed according to a fixed time length. After each sampling period is completed, the sliding time window slides forward by one sampling interval to ensure that the data involved in the analysis is continuously updated. The length of the sliding time window is configured based on the scheduling cycle of the new energy base and the duration of power fluctuations, ensuring that it can fully cover the development process of a local micro-meteorological disturbance and promptly reflect the changing trend of power output at the new energy stations.

[0022] Subsequently, within the sliding time window, the active power data corresponding to each grid connection point is collected by the synchronous phasor measurement device configured at each grid connection point. The active power data refers to the instantaneous active power measurement value actually output by each grid connection point to the public power grid, which characterizes the magnitude of the active power actually output by each grid connection point to the power grid. The larger the active power value, the higher the actual active power output of the current grid connection point to the power grid, and the smaller the active power value, the lower the actual output of the current grid connection point.

[0023] It should be noted that the synchronous phasor measurement device refers to the measurement equipment installed at the grid connection point of the new energy power station for synchronously collecting and calculating the electrical quantities of the power grid.

[0024] Active power data reflects the current actual power generation capacity of the power station and the impact of micro-meteorological disturbances on the output power. The greater the fluctuation of active power data, the more obvious the impact of local micro-meteorological disturbances such as wind speed changes, solar irradiance changes, or cloud cover on the corresponding power station. The more stable the change of active power data, the more stable the output status of the power station.

[0025] After obtaining the active power data within the sliding time window of each power station, the rate of change of active power between adjacent sampling times of each power station is first calculated. The expression for calculating the rate of change of active power at the k-th sampling time is as follows: ; in, Let be the rate of change of active power at the k-th sampling time. This represents the instantaneous active power measurement value corresponding to the k-th sampling time. This represents the instantaneous active power measurement value corresponding to the (k-1)th sampling time. The time interval between adjacent sampling times. This is the index for the sampling time.

[0026] The rate of change of active power is used to reflect the speed of change of the power output of a power station. The larger its absolute value, the more obvious the impact of external disturbances on the power station.

[0027] Subsequently, a power change rate trigger threshold is set. When the absolute value of the active power change rate corresponding to the sampling time is greater than or equal to the power change rate trigger threshold, the corresponding sampling time is recorded as the disturbance trigger time of the corresponding station.

[0028] Among them, the disturbance trigger time indicates the time node when the power station first shows obvious power fluctuations. The earlier the time, the earlier the power station is affected by local disturbances.

[0029] It should be noted that the power change rate trigger threshold is a judgment parameter used to determine whether the change in active power of a new energy power station exceeds the normal fluctuation range. It is determined based on the statistical results of the active power change rate during the historical stable operation phase of the new energy base.

[0030] After completing the statistics of disturbance trigger times for all stations, the disturbance trigger times for all stations are sorted in chronological order. The station with the earliest disturbance trigger time is selected as the benchmark station, and the active power data corresponding to the benchmark station is extracted as the benchmark sequence. The remaining stations are used as target stations to participate in the subsequent zero-lag cross-analysis.

[0031] To eliminate the dimensional influence caused by the different rated capacities of various power stations, the average active power data of the baseline sequence and the target power station are first calculated within the current sliding time window to obtain the average active power. The average active power is used to represent the average output level of the corresponding power station within the current analysis time window. The larger the value, the higher the overall output of the power station; the smaller the value, the lower the overall output of the power station.

[0032] After obtaining the average active power, the mean was removed at each sampling time to obtain the power offset of the reference station and the target station, respectively. The calculation expressions are as follows: ; in, This represents the power offset at the k-th sampling time of the reference station. This represents the power offset at the k-th sampling time of the target power station. The instantaneous active power measurement value corresponding to the k-th sampling time of the reference station. The average active power of the benchmark station. The instantaneous active power measurement value corresponding to the k-th sampling time of the target power station. The average active power of the target power station. This is the index value for the sampling time.

[0033] The power offset is used to reflect the instantaneous deviation of each sampling time from the average output level. The larger the absolute value, the more obvious the influence of local micro-meteorological disturbances at the current moment. The smaller the absolute value, the more stable the current power change.

[0034] Subsequently, zero-hysteresis crossover analysis is performed under zero-time-delay conditions. This involves calculating the Pearson correlation coefficient between the active power data of each target station and the reference sequence under zero-time-delay conditions based on the power offset, thereby obtaining the zero-hysteresis crossover coefficient between the reference station and each target station. The expression for this coefficient is as follows: ; in, is the zero-hysteresis crossover coefficient between the reference station and the target station, with a value range of [-1, 1]; This represents the power offset at the k-th sampling time of the reference station; This represents the power offset at the k-th sampling time of the target power station; This is the index value of the sampling time. This represents the total number of sampling moments within the sliding time window.

[0035] The zero-hysteresis crossover coefficient is used to characterize the consistency of the power change trends of two stations at the same sampling time. When its value is closer to 1, it indicates that the consistency of the power change direction and magnitude of the two stations is higher, indicating that they are still under the control of the same micro-meteorological disturbance. When its value is closer to 0, it indicates that the correlation between the power changes of the two stations is weak, indicating that the target station has gradually moved away from the disturbance state of the reference station. When its value is closer to -1, it indicates that the power change trends of the two stations are opposite, indicating that they are in different disturbance stages or are affected by opposite regulation effects.

[0036] Finally, the zero-hysteresis crossover coefficient and active power change rate corresponding to each target station are jointly analyzed: When the zero-hysteresis cross coefficient corresponding to the target power station is higher than the preset relevant judgment threshold, and the direction of the active power change rate corresponding to the target power station is consistent with the direction of the active power change rate corresponding to the benchmark power station, it is determined that the target power station has entered the state of wave front transit. Otherwise, it is determined that the target station has not yet entered the state of the wave front passing through, and the next round of zero-lag cross-analysis will continue to be performed according to the active power data updated by the sliding time window.

[0037] It should be noted that the preset relevant judgment threshold is used to determine whether the correlation between the power change of the target station and the benchmark station has decreased significantly. It is determined based on the statistical results of the zero-hysteresis cross coefficient in the historical micro-meteorological disturbance propagation process of the new energy base.

[0038] The transit status of the wave front is used to characterize whether local micro-meteorological disturbances have spread to the corresponding stations. The determination result serves as the basis for subsequent identification of stations covered by the wave front and estimation of the disturbance's persistence.

[0039] In step S2, the transit status of each station's wave front is read, all stations are screened one by one, and stations that have entered the wave front transit status are identified as wave front covered stations.

[0040] After identifying the power stations covered by the fluctuation front, the current upward reserve capacity and the current downward reserve capacity of each power station covered by the fluctuation front are read. The current upward reserve capacity represents the maximum power margin that the power station can continue to increase from its current output power, and the current downward reserve capacity represents the maximum power margin that the power station can continue to decrease from its current output power. The smaller value between the current upward reserve capacity and the current downward reserve capacity is taken as the current adjustable capacity. The current adjustable capacity reflects the power margin that the power station can currently participate in power regulation.

[0041] Simultaneously, the average active power of each power station covered by the convective wave front is read within the current sliding time window. The current adjustable capacity is divided by the average active power, and then multiplied by the length of the sliding time window to calculate the disturbance absorption capacity of each power station covered by the convective wave front. The disturbance absorption capacity is used to characterize the equivalent energy reserve of the power station in the current operating state to continue to absorb local micro-meteorological disturbances and maintain power regulation capability. The larger the value, the stronger the continuous regulation capability of the power station, and the longer it can absorb external disturbances without the decay of regulation capability. The smaller the value, the lower the remaining regulation margin of the power station and the weaker its ability to continuously undertake disturbance compensation tasks.

[0042] After completing the calculation of the disturbance absorption capacity of all stations covered by the wave front, the active power change rate corresponding to the end of the current sliding time window of each station covered by the wave front is read simultaneously to reflect the speed at which the actual output power of the station changes due to local micro-meteorological disturbances. The larger the absolute value, the more intense the current wave development and the faster the disturbance consumes the station's adjustable capacity; the smaller the absolute value, the more gradual the power change and the longer the station can maintain the current regulation state.

[0043] Subsequently, the duration of fluctuations corresponding to each station covered by the fluctuation front is calculated using the disturbance absorption capacity and the active power change rate corresponding to the end of the current sliding time window. The calculation expression is as follows: ; in, Let be the duration of the fluctuations covered by the i-th fluctuation front. Let be the disturbance absorption capacity of the station covered by the i-th fluctuation front. Let be the rate of change of active power at the end of the sliding time window of the station covered by the i-th fluctuation front. The duration of the current sliding time window. The index value of the field covered by the fluctuation front.

[0044] The duration of fluctuations reflects the estimated duration for which the current power station can continuously resist the impact of local micro-meteorological disturbances based on its existing disturbance absorption capacity. The larger the value, the more sufficient the remaining regulation capacity of the power station is, and the longer it can continuously undertake power regulation tasks. The smaller the value, the faster the remaining disturbance absorption capacity of the power station will be exhausted, and it is necessary to prioritize reducing the allocation ratio of subsequent regulation tasks.

[0045] In step S3, the residual disturbance impact of the current wave front coverage area is quantified based on the wave duration corresponding to each wave front coverage station, and a residual energy index is generated.

[0046] Calculate the average duration of fluctuations across all stations covered by the undulating front. The average duration of fluctuations reflects the overall resilience of the area covered by the undulating front to local micro-meteorological disturbances. A larger value indicates that most stations within the undulating front coverage area have a greater disturbance absorption margin and can maintain power regulation for a longer period of time. A smaller value indicates that the regulation capacity of stations within the undulating front coverage area is depleted more quickly, requiring earlier adjustment of power regulation strategies.

[0047] Subsequently, the residual energy index is calculated by combining the average duration of fluctuations and the duration of fluctuations corresponding to the stations covered by each fluctuation front. The calculation expression is as follows: ; in, The residual energy index. The duration of fluctuations at the site covered by the i-th fluctuation front. The average duration of fluctuation, The total number of venues covered by the fluctuating forward. To cover the field index value for the fluctuating forward, It is a natural constant.

[0048] The residual energy index reflects the remaining duration of disturbance impact within the coverage area of ​​the current oscillation front. It is a dimensionless parameter. The larger the value, the shorter the residual duration of the disturbance impact on the overall site covered by the current oscillation front. The disturbance impact is in its later stage, and the local micro-meteorological disturbance is about to decay completely. It is necessary to reduce the proportion of fast power regulation resources and shift the regulation focus to slow-varying tracking. The smaller the value, the stronger the residual duration of the disturbance impact. It is necessary to increase the proportion of fast power regulation resources to cope with the continuous disturbance.

[0049] After calculating the residual energy index, the power regulation target value for the current dispatch cycle of the renewable energy base is read. The power regulation target value represents the amount of active power adjustment that the renewable energy base needs to perform as a whole. When the power regulation target value is greater than 0, it means that the renewable energy base needs to increase the grid-connected active power; when the power regulation target value is less than 0, it means that the renewable energy base needs to reduce the grid-connected active power; the larger its absolute value, the greater the power adjustment range corresponding to the current grid dispatch demand.

[0050] Subsequently, the power regulation target value is decomposed based on the residual energy index, and the power regulation target value of the new energy base is decomposed into basic slow-changing regulation quantity and dynamic fast-changing regulation quantity.

[0051] First, calculate the dynamic rapid adjustment ratio based on the residual energy index: ; in, The residual energy index. This represents the dynamic fast-change regulation ratio, used to determine the proportion of the current power regulation target value that needs to be used for rapid response to disturbances; the larger the value, the higher the degree of residual disturbance, and the more regulation capacity needs to be allocated to quickly compensate for the power offset caused by the fluctuation front.

[0052] Calculate the basic slow-change adjustment ratio based on the dynamic fast-change adjustment ratio: ; in, It represents the basic slow-change regulation ratio, which is used to undertake the task of smoothing the overall power of the new energy base.

[0053] The dynamic fast-change regulation ratio and the basic slow-change regulation ratio are multiplied by the power regulation target value to calculate the dynamic fast-change regulation amount and the basic slow-change regulation amount. The dynamic fast-change regulation amount is used to quickly respond to short-term power changes caused by the wave front, while the basic slow-change regulation amount is used to maintain the overall power output trend of the new energy base.

[0054] The negative sequence component amplitudes of the power plants connected to the grid at each power plant covered by the ripple front were detected. The negative sequence component amplitudes were obtained by collecting the three-phase voltage phasors from the synchronous phasor measurement devices installed at each power plant's grid connection point, and then calculating them through symmetrical component transformation. The calculation expression is as follows: ; in, The magnitude of the negative-order component; , , These represent the three-phase voltage phasors respectively; Indicates the rotation factor: , It is a natural constant. The imaginary unit, The index value of the field covered by the fluctuation front.

[0055] The magnitude of the negative sequence component is used to reflect the degree of three-phase electrical imbalance at each substation's grid connection point. The larger the value, the more obvious the deviation of the current substation's three-phase voltage from the symmetrical state, and the lower its ability to withstand rapid power regulation. The smaller the value, the more stable the current substation's electrical operation, and the more capable it is of undertaking higher frequency power regulation tasks.

[0056] The current negative sequence component amplitude is compared with the average negative sequence component value under historical stable operating conditions to calculate the negative sequence offset rate: ; in, Negative order offset rate; This represents the average value of the negative-order components obtained statistically within a historical stable operating time window. The magnitude of the negative-order component. The index value of the field covered by the fluctuation front.

[0057] The negative sequence offset rate is used to reflect the degree of change of the current electrical imbalance state of the station relative to the normal operating state. The larger the value, the more obvious the increase of the current negative sequence disturbance and the more obvious the decrease in the station's ability to withstand rapid power regulation.

[0058] A negative order correction coefficient is generated based on the negative order offset rate to characterize the degree of capacity attenuation when each power station undertakes rapid power regulation tasks. Its calculation expression is as follows: ; in, This is a negative order correction coefficient. This is the negative order offset rate.

[0059] The negative sequence correction coefficient is used to reflect the degree of influence of the current electrical state of the power station on the rapid power regulation capability. The closer its value is to 1, the more stable the current electrical state of the power station is, and the higher the proportion of dynamic rapid regulation tasks it can undertake. The smaller its value is, the more obvious the negative sequence disturbance of the current power station is, and the proportion of rapid power regulation tasks it undertakes needs to be reduced.

[0060] It should be noted that when a power station covered by a disturbance front simultaneously meets the following two conditions, the attenuation effect of the negative sequence correction coefficient will not be applied to it: the duration of the disturbance at that power station is less than a preset proportion of the average duration of the disturbances at all power stations covered by the disturbance front; and the amplitude of the current negative sequence component at that power station does not exceed the limit specified in the grid connection standard. In this case, it indicates that the power station is in a rapidly changing phase of disturbance impact, and priority should be given to ensuring the full utilization of its rapid adjustment capability to maintain the power balance response speed during the propagation of local disturbances.

[0061] When the negative sequence offset rate is less than or equal to 0, it indicates that the current negative sequence component has not exceeded the historical stable level. It is considered that the station has normal rapid adjustment capability. The negative sequence correction coefficient is set to 1 to keep the dynamic rapid adjustment amount from decaying. When the negative sequence offset rate is greater than 0, it indicates that the electrical imbalance of the current station has increased, the amplitude of the negative sequence component of the current station has increased, the three-phase electrical symmetry has decreased, and the negative sequence correction coefficient decreases as the negative sequence offset rate increases. This is used to limit the impact of rapid adjustment tasks on stations with unstable electrical conditions.

[0062] Subsequently, the negative order correction factor is introduced into the current adjustable capacity to obtain the corrected adjustable carrying capacity: ; in, This indicates the adjusted load-bearing capacity. Indicates the current adjustable capacity. Indicates the negative order correction coefficient. The index value of the field covered by the fluctuation front.

[0063] The regulation capacity reflects the actual ability of the power station covered by the fluctuation front to undertake rapid regulation tasks. The larger the value, the more the power station has both a large remaining regulation space and good grid-connected electrical stability; the smaller the value, the more the rapid regulation capability of the power station is limited by the current negative sequence disturbance.

[0064] Subsequently, the dynamic rapid adjustment allocation ratio is calculated based on the revised adjustment capacity: ; in, This indicates the proportion of dynamic rapid adjustment. This indicates the adjusted load-bearing capacity. The total number of venues covered by the fluctuating forward. The index value of the field covered by the fluctuation front.

[0065] Based on the dynamic rapid change adjustment allocation ratio, the dynamic rapid change adjustment is allocated to obtain the actual dynamic rapid change adjustment undertaken: ; in, This refers to the actual dynamic and rapid adjustment amount undertaken. This indicates the proportion of dynamic rapid adjustment. For dynamic and rapidly changing adjustment, The index value of the field covered by the fluctuation front.

[0066] For basic slow-varying regulation tasks, due to their low rate of change, their impact on the three-phase imbalance at the grid connection point is relatively small. Therefore, the basic slow-varying regulation amount is allocated using the adjustable capacity ratio of the power station to obtain the actual basic slow-varying regulation amount undertaken: ; in, The allocation ratio of the basic slow-varying adjustment quantity. Indicates the current adjustable capacity. The total number of venues covered by the fluctuating forward. To cover the field index value for the fluctuating forward, This refers to the actual, slowly varying adjustment amount that is undertaken. It is a basic slow-varying adjustment quantity.

[0067] Finally, the actual dynamic fast-change regulation amount undertaken is superimposed with the actual basic slow-change regulation amount undertaken to generate the power regulation command covering the power station of the fluctuation front.

[0068] The power regulation command consists of a basic slow-change regulation demand and a dynamic fast-change regulation demand after negative sequence state correction. It is used to control the corresponding power station to perform differentiated power regulation, so that the new energy base can dynamically adjust the power distribution according to the duration of the disturbance, the regulation capability of the power station and the grid-connected electrical status under the influence of local micro-meteorological disturbances.

[0069] In step S4, power regulation commands for each power station covered by the ripple front are sent to the power station-side converter control unit to execute power adjustment actions. After the power regulation commands are sent, voltage harmonic distortion data at each power station's grid connection point are collected in real time to assess the impact of the current power regulation action on the grid-connected electrical status.

[0070] Among them, voltage harmonic distortion data are collected by power quality monitoring devices installed at the grid connection points of each power station covered by the wave front. The power quality monitoring devices acquire the three-phase voltage waveforms at the grid connection points according to the preset sampling period, and perform fast Fourier transform on the three-phase voltage waveforms at the grid connection points to obtain the fundamental voltage amplitude and the amplitudes of each harmonic voltage.

[0071] It should be noted that the power station-side converter control unit refers to the real-time control equipment deployed inside the new energy power station, used to receive power regulation commands and control the output power of the new energy power generation unit; the power quality monitoring device refers to the monitoring equipment installed at the grid connection point of the new energy power station, used to continuously collect and analyze the voltage and current waveform quality of the power grid.

[0072] The voltage harmonic distortion rate of each power station grid connection point covered by the wave front is calculated based on the voltage components of each harmonic. The calculation expression is as follows: ; in, Indicates voltage harmonic distortion rate; This represents the amplitude of the h-th harmonic voltage; Indicates the amplitude of the fundamental voltage. Indicates the maximum harmonic order. Indicates the harmonic order index value. The index value of the field covered by the fluctuation front.

[0073] Voltage harmonic distortion rate is used to reflect the degree of influence of the current power regulation action on the voltage waveform quality at the grid connection point. The larger the value, the higher the degree of voltage waveform distortion generated during the power regulation process, indicating that the current regulation action causes more obvious disturbance to the electrical state of the power grid; the smaller the value, the weaker the impact of the regulation action on the voltage waveform, and the more stable the grid connection operation.

[0074] Furthermore, to avoid evaluation bias caused by differences in voltage levels and load scales at different substations, current harmonic data corresponding to the grid connection points of each substation were collected, and the current harmonic distortion rate was calculated: ; in, Indicates the harmonic distortion rate of the current; This represents the amplitude of the h-th harmonic current. Indicates the reference load current value. Indicates the maximum harmonic order. Indicates the harmonic order index value. The index value of the field covered by the fluctuation front.

[0075] The current harmonic distortion rate reflects the degree of harmonic variation on the current side during the current power regulation process. The larger the value, the more obvious the current distortion caused by the regulation action, and the stronger the impact on the power quality on the load side.

[0076] Dividing the voltage harmonic distortion rate by the current harmonic distortion rate yields the power impact assessment quantity, which characterizes the relative relationship between voltage-side and current-side harmonic changes caused by the current power regulation action. A larger power impact assessment quantity indicates a more pronounced voltage distortion response per unit current harmonic change, suggesting a reduced match between the current power regulation action and the grid connection impedance characteristics, potentially leading to deterioration of voltage-side power quality. Conversely, a smaller power impact assessment quantity indicates a relatively weaker voltage harmonic response, suggesting a smaller impact of the current power regulation action on the grid-connected system.

[0077] It should be noted that when the current harmonic distortion rate is less than the preset minimum distortion rate threshold, the current harmonic level is determined to be extremely low, and the power impact evaluation quantity is not sensitive to the adjustment action. At this time, the power impact evaluation quantity is directly set to 0, and the subsequent power impact direction judgment and supplementary correction steps are not executed to avoid mathematical calculation abnormalities.

[0078] Subsequently, to identify the direction of the electrical energy surge generated by the current adjustment action, the electrical energy surge evaluation quantity within the preset time window before the power adjustment command is executed is read, and the baseline value before execution is calculated: ; in, Indicates the baseline value before execution; This represents the energy impact assessment value corresponding to the k-th sampling time before execution; Indicates the number of sampling times before execution. This is the index value at the pre-sampling time.

[0079] The electrical energy impact benchmark value is used to represent the electrical state of the current station when no regulation action is performed.

[0080] After the adjustment command is executed, the post-execution power impact assessment value is read, and the adjustment impact change rate is calculated by combining it with the baseline value before execution: ; in, Indicates the rate of change of the adjustment shock; This indicates the energy impact assessment quantity after execution; This represents the baseline value before execution.

[0081] The rate of change of the regulation impact is used to reflect the direction of change of the grid-connected electrical state caused by the current power regulation action. The larger the value, the more significant the increase in voltage harmonic response after the execution of the regulation command compared to before the regulation, indicating that the current regulation strategy produces a positive power impact, that is, aggravates power quality disturbances; the smaller the value, the more significant the power quality deterioration caused by the regulation action.

[0082] The direction of the electrical energy impact is determined based on the rate of change of the adjustment impact. When the rate of change of the adjustment impact is greater than 0, it is determined that the direction of the enhanced electrical energy impact generated by the current adjustment action of the power station covered by the wave front is insufficient, indicating that the executed power adjustment amount is not well matched with the current grid impedance state, and the corresponding adjustment command needs to be supplemented and corrected. When the rate of change of the regulation impact is less than or equal to 0, the direction of the suppressed power impact generated by the current regulation action of the wave front covering the station is determined, indicating that the current regulation command has not increased the power quality disturbance, and the current regulation command continues to be executed.

[0083] The power regulation command for the power station covered by the wave front that generates the enhanced electrical energy impact direction is supplemented and corrected. The supplemented and corrected power command is generated based on the rate of change of the impact, and its calculation expression is as follows: ; in, This indicates a supplementary power correction command; Indicates a power adjustment command. Indicates the rate of change of the adjustment shock; For a sign function, when When the value is greater than 0, the value is 1. When the value is less than 0, it takes the value of -1; The preset correction attenuation coefficient, whose value range is less than 1, is used to control the supplementary correction amplitude, so that the final adjustment command is consistent with the original adjustment command. Under the premise of ensuring that the power adjustment target is basically achieved, the power quality disturbance is effectively suppressed, and the over-correction is avoided so that the adjustment target cannot be achieved.

[0084] The supplementary power correction command is used to fine-tune the amplitude of the current regulation action while keeping the overall direction of power regulation unchanged, so as to reduce the adverse effects on the grid-connected electrical state. Its correction amplitude increases with the rate of change of regulation impact. When the rate of change of regulation impact is larger, it means that the power quality disturbance caused by the current regulation action is more obvious, and stronger amplitude fine-tuning correction is required.

[0085] Finally, the power adjustment command and the supplementary power correction command are superimposed to obtain the final compensated power adjustment command to be executed: ; in, This indicates the final power adjustment command after compensation and correction; This indicates a supplementary power correction command; This indicates a power adjustment command.

[0086] By collecting voltage harmonic distortion data after regulation is executed and performing closed-loop correction of power regulation commands according to the direction of power surge, the power regulation process of the new energy base cluster can be dynamically adjusted according to the real-time grid-connected electrical status, reducing power quality fluctuations caused by regulation actions.

[0087] Finally, it should be noted that in this paper, relational terms such as first and second are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations.

[0088] Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0089] In this document, the singular forms “a,” “an,” and “the” may also include the plural forms unless the context clearly indicates otherwise. It should also be understood that terms such as “comprising / including” or “having” specify the presence of the stated features, integrals, steps, operations, components, parts, or combinations thereof, but do not preclude the possibility of the presence or addition of one or more other features, integrals, steps, operations, components, parts, or combinations thereof. Meanwhile, the term “and / or” as used in this specification includes any and all combinations of the associated listed items.

[0090] The various embodiments in this specification are described in a progressive manner. Each embodiment focuses on the differences from other embodiments. The various embodiments can be combined as needed, and the same or similar parts can be referred to each other.

[0091] The above description of the disclosed embodiments will enable those skilled in the art to make or use various modifications to these embodiments. It will be readily apparent to those skilled in the art that the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of this application. Therefore, this application is not to be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A new energy cluster power regulation optimization decision-making method, characterized in that: Includes the following steps: Step S1: Set a sliding time window, read the active power data of each grid-connected point in the new energy base within the sliding time window, perform zero-lag cross-analysis based on the active power data, and determine the wave front transit status of each station based on the results of the zero-lag cross-analysis. Step S2: Based on the transit status of the wave front, screen and identify the stations covered by the wave front, collect the adjustable capacity of the stations covered by the wave front and analyze the disturbance absorption capacity, and use the disturbance absorption capacity to calculate the duration of the wave. Step S3: Calculate the residual energy index based on the duration of the fluctuation, read the power regulation target value of the new energy base, decompose the power regulation target value based on the residual energy index, detect the negative sequence component amplitude of the grid connection point of each fluctuation front covered by the power station, and generate the power regulation command of each fluctuation front covered by the power station based on the decomposition results. Step S4: After issuing and executing the power regulation command, collect the voltage harmonic distortion data of each power station grid connection point covered by the wave front and assess the direction of the power impact. Based on the direction of the power impact, determine whether to supplement and correct the power regulation command.

2. The new energy cluster power regulation optimization decision-making method according to claim 1, characterized in that: In step S1, a sliding time window is set. The sliding time window refers to a data analysis interval constructed according to a fixed time length. Whenever a sampling period is completed, the sliding time window slides forward by one sampling interval. Within the sliding time window, the active power data corresponding to each grid connection point is collected by the synchronous phasor measurement device configured at each grid connection point. The active power data refers to the instantaneous active power measurement value actually output by each grid connection point to the public power grid. Calculate the rate of change of active power between adjacent sampling times at each station; When the absolute value of the active power change rate corresponding to the sampling time is greater than or equal to the power change rate trigger threshold, the corresponding sampling time will be recorded as the disturbance trigger time of the corresponding station. The station with the earliest disturbance trigger time is selected as the reference station, and the active power data corresponding to the reference station is extracted as the reference sequence. All other stations are used as target stations.

3. The new energy cluster power regulation optimization decision-making method according to claim 2, characterized in that: In step S1, the average active power data of the reference sequence and the target station are calculated within the current sliding time window to obtain the average active power. The power offset of the reference station and the target station is obtained by removing the mean from the average active power at each sampling time. Based on the power offset, the Pearson correlation coefficient between the active power data of the target station and the reference sequence under zero time shift condition is calculated one by one to obtain the zero-hysteresis cross coefficient. When the zero-hysteresis cross coefficient corresponding to the target power station is higher than the preset relevant judgment threshold, and the direction of the active power change rate corresponding to the target power station is consistent with the direction of the active power change rate corresponding to the benchmark power station, it is determined that the target power station has entered the state of wave front transit. Otherwise, it is determined that the target station has not yet entered the state of the transit of the fluctuating front.

4. The new energy cluster power regulation optimization decision-making method according to claim 3, characterized in that: In step S2, the stations that have entered the state of wave front passage are identified as wave front covered stations. The current increase and decrease of reserve capacity of each wave front covered station are read, and the smaller value between the current increase and decrease of reserve capacity is taken as the current adjustable capacity. Divide the current adjustable capacity by the average active power, and then multiply by the length of the sliding time window to calculate the disturbance absorption capacity of each station covered by the wave front. Read the active power change rate corresponding to the end of the current sliding time window of each wave front-covered station, and calculate the wave duration corresponding to each wave front-covered station in combination with the disturbance absorption capacity.

5. The new energy cluster power regulation optimization decision-making method according to claim 4, characterized in that: In step S3, the average duration of fluctuations is calculated for all stations covered by the fluctuation front; The residual energy index is calculated by combining the average duration of fluctuations and the duration of fluctuations corresponding to the stations covered by each fluctuation front. Read the power adjustment target value of the new energy base within the current scheduling cycle. The power adjustment target value represents the amount of active power adjustment that the new energy base as a whole needs to perform. The dynamic rapid adjustment ratio is calculated based on the residual energy index, and the basic slow adjustment ratio is calculated based on the dynamic rapid adjustment ratio. The dynamic fast-change regulation ratio and the basic slow-change regulation ratio are calculated by multiplying them by the power regulation target value.

6. The new energy cluster power regulation optimization decision-making method according to claim 1, characterized in that: In step S3, the negative sequence component amplitude of each wave front-covered power station grid connection point is detected. The negative sequence component amplitude is obtained by the synchronous phasor measurement device set at each power station grid connection point, which collects the three-phase voltage phasors and then calculates them through symmetrical component transformation. The current negative sequence component amplitude is compared with the average value of the negative sequence components under historical stable operating conditions to calculate the negative sequence offset rate. Generate negative order correction coefficients based on negative order offset rate; The negative sequence correction coefficient is introduced into the current adjustable capacity to obtain the corrected adjustable carrying capacity. The dynamic fast-change adjustment allocation ratio is then calculated based on the corrected adjustable carrying capacity.

7. The new energy cluster power regulation optimization decision-making method according to claim 5, characterized in that: In step S3, the dynamic rapid change adjustment amount is allocated according to the dynamic rapid change adjustment amount allocation ratio to obtain the actual dynamic rapid change adjustment amount undertaken. The base slow-varying regulation amount is allocated using the current adjustable capacity to obtain the actual base slow-varying regulation amount undertaken. The actual dynamic fast-change regulation amount undertaken is superimposed with the actual basic slow-change regulation amount undertaken to generate the power regulation command for the power station covered by the fluctuation front.

8. The new energy cluster power regulation optimization decision-making method according to claim 1, characterized in that: In step S4, the power adjustment command for each wave front covering the station is sent to the station-side converter control unit to perform the power adjustment action; After the power regulation command is issued, the three-phase voltage waveform at the grid connection point is acquired according to the preset sampling period and a fast Fourier transform is performed to obtain the amplitude of each harmonic voltage. The voltage harmonic distortion rate of each wave front-covered power station grid connection point is calculated based on the voltage components of each harmonic. At the same time, the current harmonic data corresponding to each power station grid connection point is collected and the current harmonic distortion rate is calculated. The voltage harmonic distortion rate is divided by the current harmonic distortion rate to obtain the power impact evaluation quantity. Read the power impact evaluation quantity within the preset time window before the power adjustment command is executed, and calculate the baseline value before execution.

9. The new energy cluster power regulation optimization decision-making method according to claim 8, characterized in that: In step S4, after the adjustment command is executed, the power impact evaluation value after execution is read, and the adjustment impact change rate is calculated in combination with the baseline value before execution. When the rate of change of the regulation impact is greater than 0, it is determined that the direction of the enhanced power impact generated by the current regulation action of the wave front covering the station is determined, and the corresponding regulation command is supplemented and corrected at this time. When the rate of change of the regulating impact is less than or equal to 0, the direction of the suppressive electrical energy impact generated by the current regulating action of the wave front covering the station is determined, and the current regulating command is kept in execution. When supplementing and correcting the power regulation command of the power station covered by the wave front that generates the enhanced power impact direction, the supplementary and corrected power command is generated according to the rate of change of the impact. The power adjustment command is superimposed with the supplementary power correction command to obtain the final compensated power adjustment command.

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