Energy storage regulation method for ultra-high voltage direct current sending end under differentiated wind and light power fluctuation

Abstract

The specification belongs to the technical field of direct current power transmission and energy storage control, and provides a method for regulating and controlling energy storage at an ultra-high voltage direct current sending end under differentiated wind and light power fluctuation, which comprises the following steps: obtaining power time sequence data of each new energy base at the ultra-high voltage direct current sending end of wind, light, fire and storage; calculating power change parameters and fluctuation characteristic indexes of each new energy base, and determining the power fluctuation type of each new energy base; performing power mutation detection, and determining the energy storage response mode of each new energy base according to the power mutation detection result, the power change parameter and the fluctuation characteristic index; determining the power fluctuation phase difference of each new energy base, performing cross-region energy storage coordinated mutual aid control according to the preset regulation and control strategy corresponding to each energy storage response mode according to the power fluctuation phase difference, and performing differentiated time sequence control of wind, light, fire and storage. The scheme can balance the operation safety of the ultra-high voltage direct current sending end power grid, the new energy consumption capacity, the service life of the energy storage device and the economic efficiency of the thermal power operation.

Description

Technical Field

[0001] The embodiments in this specification relate to the field of DC power transmission and energy storage control technology, and in particular to a method for regulating energy storage at the UHVDC sending end under differentiated wind and solar power fluctuations. Background Technology

[0002] Currently, large-scale ultra-high voltage direct current (UHVDC) transmission bases integrating wind, solar, thermal, and energy storage, centered in deserts, Gobi, and wastelands, have been put into operation. The mainstream power transmission mode is the joint packaging of multiple new energy bases and transmission via LCC-HVDC (Line Commutated Converter-High Voltage Direct Current). Due to geographical and meteorological constraints, different new energy bases in different regions exhibit significant differences in wind and solar resource endowments, resulting in two completely different power fluctuation characteristics: second-level sudden changes and hour-level gradual changes. However, existing energy storage control schemes mostly adopt uniform fixed detection thresholds and uniform charge / discharge response logic, failing to distinguish the inherent characteristics of regional fluctuations. Under sudden operating conditions, energy storage response lags and cannot quickly compensate for power gaps. In scenarios with smooth, long-term fluctuations, frequent charging and discharging of energy storage exacerbates battery cycle losses, making it difficult to adapt to the differentiated output disturbance requirements of multiple bases.

[0003] Existing control methods rely solely on fixed windows for power surge detection, lacking a quantitative mechanism for identifying fluctuation characteristics, making it difficult to accurately distinguish between sudden, gradual, and transitional disturbances. Furthermore, traditional control logic relies on a single criterion to trigger energy storage actions, which can easily lead to missed detections of high-power disturbances and false triggering of small random fluctuations. This not only affects the voltage stability of the UHV converter bus but also easily results in the ineffective waste of energy storage capacity.

[0004] Furthermore, current wind, solar, thermal, and energy storage coordinated control generally suffers from regional decoupling and fixed timing defects. It ignores regional differences in wind and solar resources, and the unified control logic leads to delayed response in sudden change scenarios and increased losses in gradual change scenarios. Moreover, the coordination timing of energy storage, thermal power, and DC is fixed and lacks differentiated timing coordination mechanisms for different types of disturbances, making it difficult to simultaneously ensure stable DC transmission, energy storage lifespan, and the economic efficiency of thermal power operation. Summary of the Invention

[0005] In view of this, embodiments of this specification provide a method for regulating energy storage at the transmitting end of an ultra-high voltage direct current (UHVDC) transmission line under differentiated wind and solar power fluctuations. One or more embodiments of this specification also relate to an energy storage regulation device at the transmitting end of an UHVDC transmission line under differentiated wind and solar power fluctuations, a computing device, and a computer-readable storage medium, to address the technical deficiencies existing in the prior art.

[0006] According to a first aspect of the embodiments of this specification, a method for regulating energy storage at the sending end of an ultra-high voltage direct current (UHVDC) transmission line under differentiated wind and solar power fluctuations is provided, comprising: Acquire power timing data of each new energy base at the UHVDC transmission end, including wind, solar, thermal, and energy storage systems. Based on the power time series data, the power change parameters and fluctuation characteristic indicators of each new energy base are calculated, and the power fluctuation type of each new energy base is determined. Power mutation detection is performed according to the preset detection criteria corresponding to each power fluctuation type. Based on the power mutation detection results, the power change parameters, and the fluctuation characteristic indicators, the energy storage response mode of each new energy base is determined for the two types of fluctuations, namely sudden change and gradual change, so as to realize differentiated SOC zoning management. The phase difference of power fluctuation in each new energy base is determined. Based on the phase difference of power fluctuation, cross-regional energy storage coordination and mutual assistance control is performed according to the preset control strategy corresponding to each energy storage response mode, and wind, solar, thermal and energy storage differentiated timing control is performed.

[0007] In one possible implementation, based on the power time-series data, the power change parameters of each new energy base are calculated, including: A sliding window of preset length is used to perform a moving average filtering process on the power time series data to obtain filtered power time series data; The net power change rate of each new energy base is obtained by performing time-by-time differentiation on the filtered power time-series data. Based on the filtered power time-series data, the power difference between the current moment and the previous moment of the set time interval is calculated to obtain the net power change of each new energy base. The net power change rate and the net power change amount are used as power change parameters for each new energy base.

[0008] In one possible implementation, the fluctuation characteristic indicators of each new energy base are calculated, including: Retrieve pre-stored historical operation correlation data of each new energy base, and extract time series samples of net power change rate within a continuous set time period from the historical operation correlation data; Based on the aforementioned net power change rate time series sample, the sample standard deviation of the power change rate and the sample mean of the absolute value of the power change rate for each new energy base are determined respectively. The fluctuation characteristic index of each new energy base is obtained by dividing the standard deviation of the power change rate sample by the mean of the absolute value of the power change rate sample.

[0009] In one possible implementation, the power fluctuation type of each new energy base is determined, including: Based on the historical operational data, the fluctuation characteristic thresholds of each new energy base are determined through a combination of offline training and online updates. The fluctuation characteristic index of each new energy base is compared with the corresponding fluctuation characteristic threshold. If the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the power fluctuation type of the current new energy base is determined to be a sudden change fluctuation. If the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the power fluctuation type of the current sending-end new energy base is determined to be a gradual change fluctuation.

[0010] In one possible implementation, power surge detection is performed according to a preset detection criterion corresponding to each of the power fluctuation types, including: If the power fluctuation type is a sudden change fluctuation, then determine whether the absolute value of the net power change exceeds a preset sudden change power change threshold to obtain a first judgment result, and determine whether the absolute value of the net power change rate exceeds a preset sudden change power change rate threshold to obtain a second judgment result. If the first judgment result and / or the second judgment result are yes, then the power change detection result is that a valid sudden change disturbance has occurred. If the power fluctuation type is a gradual fluctuation, the average power change of each new energy base is determined by the sliding window integral detection method, and it is determined whether the absolute value of the average power change exceeds the preset gradual power change threshold to obtain a third judgment result. If the third judgment result is yes, the power change detection result is that a valid gradual disturbance has occurred.

[0011] In one possible implementation, based on the power surge detection results, the power change parameters, and the fluctuation characteristic indicators, the energy storage response mode of each new energy base is determined for both sudden and gradual fluctuations, achieving differentiated SOC zoning management, including: If the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is greater than the sudden change power change rate threshold, and the power change detection result is that an effective sudden change disturbance has occurred, then the energy storage response mode is determined to be a fast response type. If the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is less than or equal to the preset gradual power change rate threshold, and the power mutation detection result is that an effective gradual disturbance has occurred, then the energy storage response mode is determined to be continuous support type. Verify the consistency between the power fluctuation type and the corresponding preset detection criterion and the energy storage response mode; otherwise, determine that the energy storage response mode is transitional.

[0012] In one possible implementation, based on the power fluctuation phase difference, cross-regional energy storage coordination and mutual assistance control is performed according to a preset control strategy corresponding to each of the energy storage response modes, including: If the phase difference of the power fluctuations of any two new energy bases is in phase or zero phase, the preset mutual assistance participation coefficient will be set to zero, and local mitigation strategies will be executed according to the energy storage response modes of the two new energy bases respectively. If the phase difference of the power fluctuations of any two new energy bases is out of phase, then the mutual assistance power, the additional power of reverse charging and discharging, and the tiered mutual assistance participation coefficient of the two new energy bases are determined respectively, and the local power command of energy storage is generated and issued to execute cross-regional energy storage coordination and mutual assistance control. Among these, cross-regional mutual assistance should be prioritized lower than local fluctuation response. The degree of local fluctuation should be assessed, and cross-regional mutual assistance should not be participated in when there is a local emergency, but should be fully utilized for mutual assistance when local resources are sufficient.

[0013] According to a second aspect of the embodiments of this specification, an ultra-high voltage direct current (UHVDC) sending-end energy storage regulation device under differentiated wind and solar power fluctuations is provided, comprising: The acquisition module is used to acquire power timing data of various new energy bases at the UHVDC transmission end, including wind, solar, thermal, and energy storage systems. The calculation module is used to calculate the power change parameters and fluctuation characteristic indicators of each new energy base based on the power time series data, and to determine the power fluctuation type of each new energy base. The detection module is used to perform power mutation detection according to the preset detection criteria corresponding to each power fluctuation type, and to determine the energy storage response mode of each new energy base for the two types of fluctuations, namely sudden change and gradual change, based on the power mutation detection results, the power change parameters and the fluctuation characteristic indicators, so as to realize differentiated SOC zoning management. The control module is used to determine the power fluctuation phase difference of each new energy base, and based on the power fluctuation phase difference, execute cross-regional energy storage coordination and mutual assistance control according to the preset regulation strategy corresponding to each energy storage response mode, and execute wind, solar, thermal and energy storage differentiated timing control.

[0014] In one possible implementation, the calculation module is specifically used to: perform a moving average filtering process on the power time series data using a sliding window of a preset length to obtain filtered power time series data; perform time-by-time differentiation operations on the filtered power time series data to obtain the net power change rate of each new energy base; calculate the power difference between the current time and the previous time of a set time interval based on the filtered power time series data to obtain the net power change of each new energy base; and use the net power change rate and the net power change as power change parameters for each new energy base.

[0015] In one possible implementation, the calculation module is specifically used to: retrieve pre-stored historical operation correlation data of each new energy base, and extract time-series samples of net power change rate within a continuously set time period from the historical operation correlation data; determine the sample standard deviation of power change rate and the sample mean of absolute power change rate for each new energy base based on the time-series samples of net power change rate; and calculate the fluctuation characteristic index of each new energy base by dividing the sample standard deviation of power change rate by the sample mean of absolute power change rate.

[0016] In one possible implementation, the calculation module is specifically used to: determine the fluctuation characteristic threshold of each new energy base based on the historical operation correlation data through a combination of offline training and online updating; compare the fluctuation characteristic index of each new energy base with the corresponding fluctuation characteristic threshold; if the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, then determine that the power fluctuation type of the current new energy base is a sudden change fluctuation; if the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, then determine that the power fluctuation type of the current sending-end new energy base is a gradual change fluctuation.

[0017] In one possible implementation, the detection module is specifically used to: if the power fluctuation type is a sudden change fluctuation, determine whether the absolute value of the net power change exceeds a preset sudden change power change threshold to obtain a first determination result, and determine whether the absolute value of the net power change rate exceeds a preset sudden change power change rate threshold to obtain a second determination result; if the first determination result and / or the second determination result are yes, then the power change detection result is that a valid sudden change disturbance has occurred; if the power fluctuation type is a gradual change fluctuation, use a sliding window integral detection method to determine the average power change of each new energy base, and determine whether the absolute value of the average power change exceeds a preset gradual change power change threshold to obtain a third determination result; if the third determination result is yes, then the power change detection result is that a valid gradual change disturbance has occurred.

[0018] In one possible implementation, the detection module is specifically used to: determine the energy storage response mode as a rapid response mode if the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is greater than the sudden change power change rate threshold, and the power change detection result is a valid sudden change disturbance; determine the energy storage response mode as a continuous support mode if the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is less than or equal to a preset gradual change power change rate threshold, and the power change detection result is a valid gradual change disturbance; verify the consistency between the power fluctuation type and the corresponding preset detection criterion and the energy storage response mode, and determine the energy storage response mode as a transition mode in other cases.

[0019] In one possible implementation, the control module is specifically used to: if the phase difference of the power fluctuations of any two new energy bases is in phase or zero phase, then set the preset mutual assistance participation coefficient to zero, and execute the local mitigation strategy according to the energy storage response mode of each of the two new energy bases; if the phase difference of the power fluctuations of any two new energy bases is out of phase, then determine the mutual assistance power, reverse charging and discharging additional power, and tiered mutual assistance participation coefficient of the two new energy bases respectively, generate and issue local energy storage power commands to execute cross-regional energy storage coordinated mutual assistance control; wherein, the priority of cross-regional mutual assistance should be lower than that of local fluctuation response, judge the degree of local fluctuation, and not participate in cross-regional mutual assistance when local emergency occurs, and fully assist when local resources are sufficient.

[0020] According to a third aspect of the embodiments of this specification, a computing device is provided, comprising: Memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, the steps of the above-mentioned method for regulating the energy storage at the UHVDC sending end under differentiated wind and solar power fluctuations are implemented.

[0021] According to a fourth aspect of the embodiments of this specification, a computer-readable storage medium is provided that stores computer-executable instructions, which, when executed by a processor, implement the steps of the above-described method for regulating energy storage at the transmission end of ultra-high voltage direct current under differentiated wind and solar power fluctuations.

[0022] The solution provided in this manual collects power time-series data from new energy bases and quantifies and calculates power change parameters and fluctuation characteristic indicators to accurately distinguish power fluctuation types. It is then equipped with differentiated abrupt change detection criteria adapted to different fluctuation characteristics. Combining the detection results, power change parameters, and fluctuation characteristic indicators, it adaptively matches different energy storage response modes. Simultaneously, it leverages the phase difference of power fluctuations between two regions to implement cross-regional energy storage power mutual assistance. Furthermore, it matches the energy storage response mode to perform differentiated time-series coordinated control of energy storage, thermal power, and UHVDC. On the one hand, it can accurately smooth out different disturbances, effectively suppressing large drops in DC power transmission, stabilizing converter bus voltage, and avoiding the risk of commutation failure. On the other hand, by leveraging cross-regional mutual assistance, it fully utilizes the spatiotemporal complementarity of regional wind and solar power, reducing the overall energy storage configuration capacity requirement. It can simultaneously take into account the operational safety of the UHVDC sending-end grid, the new energy absorption capacity, the lifespan of energy storage equipment, and the economic efficiency of thermal power operation. Attached Figure Description

[0023] Figure 1 This is a flowchart illustrating an embodiment of an ultra-high voltage direct current (UHVDC) transmission-end energy storage regulation method under differentiated wind and solar power fluctuations provided in this specification. Figure 2This is a schematic diagram illustrating the principle of an ultra-high voltage direct current (UHVDC) sending-end energy storage regulation method under differentiated wind and solar power fluctuations, provided in one embodiment of this specification. Figure 3 This is a schematic diagram illustrating the coordinated control effect under a sudden drop in photovoltaic power. Figure 4 This is a schematic diagram illustrating the coordinated control effect under a sudden surge in wind power. Figure 5 This is a schematic diagram of the structure of an ultra-high voltage direct current sending-end energy storage and control device under differentiated wind and solar power fluctuations, provided in one embodiment of this specification. Figure 6 This is a structural block diagram of a computing device provided in one embodiment of this specification. Detailed Implementation

[0024] Many specific details are set forth in the following description to provide a full understanding of this specification. However, this specification can be implemented in many other ways than those described herein, and those skilled in the art can make similar extensions without departing from the spirit of this specification. Therefore, this specification is not limited to the specific implementations disclosed below.

[0025] The terminology used in one or more embodiments of this specification is for the purpose of describing particular embodiments only and is not intended to be limiting of the one or more embodiments of this specification. The singular forms “a” and “the” as used in one or more embodiments of this specification and the appended claims are also intended to include the plural forms, unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used in one or more embodiments of this specification refers to and includes any or all possible combinations of one or more associated listed items.

[0026] It should be understood that although the terms first, second, etc., may be used to describe various information in one or more embodiments of this specification, such information should not be limited to these terms. These terms are only used to distinguish information of the same type from one another. For example, first may also be referred to as second without departing from the scope of one or more embodiments of this specification, and similarly, second may also be referred to as first. Depending on the context, the word "if" as used herein may be interpreted as "when," "when," or "in response to a determination."

[0027] This specification provides a method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations. This specification also relates to an energy storage regulation device at the UHVDC transmission end under differentiated wind and solar power fluctuations, a computing device, and a computer-readable storage medium, which will be described in detail in the following embodiments.

[0028] Combination Figure 1 and Figure 2 As shown, Figure 1 and Figure 2 A flowchart illustrating a method for regulating energy storage at the sending end of an ultra-high voltage direct current (UHVDC) transmission line under differentiated wind and solar power fluctuations, according to an embodiment of this specification, is shown, specifically including the following steps: Step 110: Obtain the power timing data of each new energy base at the UHVDC transmission end, including wind, solar, thermal, and energy storage.

[0029] In this step, the wind-solar-thermal-storage UHVDC sending end refers to the sending end collection power system that is equipped with a combined power source of wind power, photovoltaic, thermal power and energy storage, and sends out power through LCC-HVDC; the power time series data refers to the continuous time series of power related to wind power, photovoltaic and energy storage of each new energy base collected at high frequency by PMU (Phasor Measurement Unit).

[0030] Step 120: Based on the power time series data, calculate the power change parameters and fluctuation characteristic indicators of each new energy base, and determine the power fluctuation type of each new energy base.

[0031] In this step, the power change parameters include the net power change rate and the net power change amount, which mainly characterize the speed and amplitude of power fluctuations. The fluctuation characteristic index is obtained by dividing the standard deviation of the change rate by the mean of the absolute value of the change rate, which is used to quantify the inherent fluctuation attributes of regional wind and solar power. The higher the value, the more likely the region is to experience sudden changes and disturbances. The power fluctuation types are divided into sudden change type (large fluctuations at the second level) and gradual change type (smooth fluctuations at the minute / hour level).

[0032] Step 130: Perform power mutation detection according to the preset detection criteria corresponding to each power fluctuation type, and determine the energy storage response mode of each new energy base for the two types of fluctuations, namely sudden change and gradual change, based on the power mutation detection results, power change parameters and fluctuation characteristic indicators, so as to realize differentiated SOC (State of Charge) zoning management.

[0033] In this step, the power surge detection index uses a dedicated threshold to identify effective high-power disturbances and filter out small random fluctuations; the energy storage response mode is divided into three types of energy storage control logic: fast response, continuous support, and transition.

[0034] Step 140: Determine the power fluctuation phase difference of each new energy base, and based on the power fluctuation phase difference, execute cross-regional energy storage coordination and mutual assistance control according to the preset control strategy corresponding to each energy storage response mode, and execute wind, solar, thermal and energy storage differentiated timing control.

[0035] In this step, the power fluctuation phase difference refers to the comparison result of the power rise and fall trends of the two bases, specifically divided into out-of-phase, in-phase, and zero-phase; cross-regional energy storage coordination and mutual assistance refers to the charging and discharging of one region and the complementary absorption of power deviation when the fluctuations of the two bases are out of phase; wind, solar, thermal and energy storage differentiated timing control refers to matching the dedicated energy storage, thermal power and DC collaborative adjustment timing for different energy storage modes.

[0036] This embodiment, by establishing a complete hierarchical adaptive control link, can solve the shortcomings of traditional unified control in adapting to the differences in wind and solar resources in two regions, from raw power acquisition, fluctuation quantification and identification, disturbance detection, adaptive switching of energy storage mode, to cross-regional energy storage mutual assistance and multi-power source time-series coordinated integrated control. It can simultaneously achieve multiple goals such as grid stability, reliable energy storage, and economical operation of thermal power.

[0037] Taking a ±800kV ultra-high voltage direct current (UHVDC) transmission project as an example, the wind-solar-thermal-storage UHVDC transmission end includes the first new energy base (4500MW wind power and 1500MW photovoltaic) and the second new energy base (2200MW wind power and 2300MW photovoltaic), with energy storage of 1000MW / 4000MWh and thermal power of 4000MW. The proportion of new energy transmission is about 53%~54%.

[0038] In this system, the energy storage control system plays a crucial role in smoothing out power fluctuations from new energy sources and providing emergency power support. In practical applications, there are significant differences in wind and solar resources between the first and second new energy bases: Regarding wind energy resources, the First New Energy Base is located in the heart of the Loess Plateau, with abundant wind resources. The average annual wind speed at a height of 100m is approximately 5.4~7.3m / s, and the wind power density is 119.9~307.6W / m³. 2 The second new energy base is located in an area with a low average annual wind speed of about 1.76 m / s. The duration of wind speeds ≥3 m / s accounts for only 61.3%, while the low wind speed range of 4~6 m / s accounts for as much as 44.7%.

[0039] Regarding solar energy resources, the annual total solar radiation at the first new energy base ranges from 5280 to 5710 megajoules per square meter, with 190 to 250 days of usable solar energy per year. The peak sunshine duration at the second new energy base is 5.31 hours per day, with a total horizontal radiation of approximately 1601.6 kWh / m². 2 The annual equivalent utilization hours are approximately 1716 hours.

[0040] The differences in wind and solar resources between the two locations result in drastically different power fluctuation characteristics: In the first new energy base, due to sudden changes in wind speed and rapid cloud cover, power fluctuations are mainly characterized by sudden drops / rises, with a time scale of seconds and a large rate of change; In the second new energy base, due to continuous low wind speeds and dust accumulation, power fluctuations are mainly characterized by gradual decay, with a time scale of minutes to hours and a small rate of change.

[0041] In practical applications, a synchronous phasor measurement unit can be deployed at the sending-end AC bus to independently monitor the two new energy collection areas, the first and second new energy bases, and collect the following electrical quantities in real time: Active power of wind power in the First New Energy Base The rated capacity is 4500MW; Photovoltaic active power of the First New Energy Base The rated capacity is 1500MW; Wind power active power of the second new energy base The rated capacity is 2200MW; Photovoltaic active power of the second new energy base The rated capacity is 2300MW; Active power at the thermal power unit collection point The total rated capacity is 4000MW; Energy storage active power of the First New Energy Base The rated power is 600MW and the rated capacity is 2400MWh; Energy storage active power of the second new energy base The rated power is 400MW and the rated capacity is 1600MWh; DC transmission power of LCC rectifier station ; In addition to the power timing data mentioned above, it is also necessary to collect the voltage of the sending-end converter bus. .

[0042] Furthermore, with the sampling period By collecting the above electrical quantities, a real-time state vector of the system can be constructed. The details are as follows: (1) In practical applications, sampling period The value can be 1~10ms.

[0043] In one embodiment, based on power time-series data, the power variation parameters of each new energy base are calculated, specifically including: First, a sliding window of preset length is used to perform a moving average filter on the power time series data to obtain the filtered power time series data.

[0044] In this step, the moving average filtering refers to using a fixed window to smooth the original power time series, which can filter out acquisition noise and small random spikes.

[0045] Then, the time-by-time derivative operation is performed on the filtered power time-series data to obtain the net power change rate of each new energy base.

[0046] In this step, the derivative is calculated time-series with respect to the time-series differential of the filtered continuous power to obtain the instantaneous net power change rate, which can reflect the speed of power fluctuation.

[0047] Specifically, a sliding window average filter can be applied to the real-time power of various power sources, thereby enabling the calculation of the net power and its rate of change in the two regions of the first and second new energy bases.

[0048] In this embodiment, the total net power of the first new energy base can be expressed as: (2) in, The total net power of the first new energy base at time t. Let t be the active power of wind power in the first new energy base. The active power of the photovoltaic power generation at the first new energy base at time t.

[0049] The total net power of the second new energy base can be expressed as: (3) in, The total net power of the second new energy base at time t. Let t be the active power of wind power at the second new energy base. Let t be the photovoltaic active power of the second new energy base.

[0050] The net power change rates of the first and second new energy bases can be expressed as follows: (4) (5) in, Let be the net power change rate of the first new energy base at time t. Let t be the net power change rate of the second new energy base.

[0051] Next, based on the filtered power time series data, the power difference between the current moment and the previous moment of the set time interval is calculated to obtain the net power change of each new energy base.

[0052] In this embodiment, the net power changes of the first new energy base and the second new energy base can be expressed as follows: (6) (7) in, Let t be the net power change of the first new energy base. Let t be the net power change of the second new energy base. To set the interval duration, it is used to calculate the power difference between adjacent time points, i.e., the net power change, which characterizes the amplitude of a single fluctuation. In practical applications, The time can be 0.1 to 1 second.

[0053] Ultimately, the net power change rate and net power change amount will be used as the power change parameters for each new energy base.

[0054] This embodiment eliminates noise interference in the power acquisition stage and synchronously quantifies two core parameters: fluctuation rate and fluctuation amplitude. This provides quantitative data support for distinguishing between sudden and gradual disturbances, avoids the problem of misjudgment of disturbances caused by noise, and improves the effectiveness and accuracy of subsequent control stages.

[0055] In one embodiment, calculating the fluctuation characteristic indicators of each new energy base specifically includes: First, retrieve the historical operation data of each new energy base that has been stored in advance, and extract the time series sample of net power change rate within a continuous set time period from the historical operation data.

[0056] In this step, historical operational data refers to relevant data such as long-term wind and solar power output, meteorology, disturbance events, and energy storage operation records of the base; net power change rate time series sample refers to the numerical sequence of all net power change rates over a long time scale.

[0057] Then, based on the time series samples of net power change rate, the sample standard deviation of power change rate and the sample mean of absolute power change rate of each new energy base are determined respectively.

[0058] In this step, the standard deviation of the power change rate sample is used to characterize the dispersion of the power change rate; the larger the value, the more drastic the fluctuation. The absolute value of the power change rate sample mean is used to characterize the average fluctuation amplitude of the power.

[0059] Finally, the fluctuation characteristic index of each new energy base is obtained by dividing the standard deviation of the power change rate sample by the mean of the absolute value of the power change rate sample.

[0060] Specifically, based on the historical operational correlation data of the first and second new energy bases, a benchmark database of fluctuation characteristics for the two locations can be established, and the fluctuation characteristic indicators can be defined as follows: (8) in, This is a collection of time-series samples of the net power change rate of each new energy base, serving as a volatility characteristic indicator. The standard deviation of the power change rate is the sample standard deviation. This represents the sample mean of the absolute value of the power change rate.

[0061] Therefore, The larger the value, the more abrupt the power fluctuations of the new energy base become. The smaller the value, the more gradual the power fluctuation of the new energy base is.

[0062] This embodiment quantifies the inherent wind and light fluctuation attributes of a region through long-term historical data, thereby generating quantifiable fluctuation characteristic indicators, achieving an objective distinction between the two types of fluctuation base characteristics, and overcoming the limitations of manually classifying regional fluctuation types based on experience.

[0063] In one embodiment, determining the power fluctuation type of each new energy base specifically includes: First, based on historical operational data, the fluctuation characteristic thresholds of each new energy base are determined through a combination of offline training and online updates.

[0064] Understandably, in the combined offline training and online update approach, the offline method relies on massive historical data to initially determine the fluctuation threshold, while the online method uses real-time perturbation samples to continuously iterate and correct the threshold; the fluctuation characteristic threshold refers to the critical value that distinguishes between sudden and gradual fluctuations.

[0065] Then, the fluctuation characteristic indicators of each new energy base are compared with the corresponding fluctuation characteristic thresholds. If the fluctuation characteristic indicator is greater than the corresponding fluctuation characteristic threshold, the power fluctuation type of the current new energy base is determined to be a sudden change fluctuation; if the fluctuation characteristic indicator is less than or equal to the corresponding fluctuation characteristic threshold, the power fluctuation type of the current sending-end new energy base is determined to be a gradual change fluctuation.

[0066] It is understandable that sudden fluctuations correspond to large increases or decreases in power on a second-by-second basis, with a relatively large rate of change; while gradual fluctuations correspond to a slow decay in power on a minute-by-hour basis, with a relatively small rate of change.

[0067] This embodiment sets a threshold for fluctuation characteristics, enabling the threshold to have adaptive optimization capabilities and adapt to changes in wind and solar fluctuation characteristics caused by seasonal and meteorological changes. By comparing indicators with thresholds, fluctuation types are automatically classified, providing a classification basis for regionally differentiated detection criteria.

[0068] In one embodiment, power fluctuation detection is performed according to preset detection criteria corresponding to each power fluctuation type, specifically including: If the power fluctuation type is a sudden change fluctuation, then determine whether the absolute value of the net power change exceeds the preset sudden change power change threshold to obtain the first judgment result, and determine whether the absolute value of the net power change rate exceeds the preset sudden change power change rate threshold to obtain the second judgment result. If the first judgment result and / or the second judgment result are yes, then the power change detection result is that a valid sudden change disturbance has occurred.

[0069] In this scenario, the threshold for sudden power change can be set to 480MW, which is the minimum amplitude threshold for sudden disturbances; the threshold for sudden power change rate can be set to 50MW / s, which is the minimum fluctuation rate threshold for sudden disturbances.

[0070] If the power fluctuation type is a gradual fluctuation, the average power change of each new energy base is determined by the sliding window integral detection method, and it is determined whether the absolute value of the average power change exceeds the preset gradual power change threshold to obtain the third judgment result. If the third judgment result is yes, the power change detection result is that a valid gradual disturbance has occurred.

[0071] In this scenario, sliding window integral detection refers to calculating the average power change through integration over a 30-second long window, which is suitable for smooth and gradual fluctuations. The threshold for gradual power change can be set to 225MW, which is the effective amplitude threshold for gradual disturbances. Effective disturbances refer to large power fluctuations that exceed the threshold and require energy storage intervention to smooth them out. Small random fluctuations are not considered effective disturbances.

[0072] This embodiment configures differentiated detection logic for two types of fluctuations. It achieves millisecond-level fast identification in sudden change scenarios and suppresses short-term spikes that trigger false alarms in gradual change scenarios. This greatly reduces the problems of missed detection of sudden change disturbances and frequent false actions in gradual change scenarios, and reduces the ineffective charging and discharging losses of energy storage.

[0073] In this embodiment, considering the abrupt fluctuation characteristics of the first new energy base, a short window and a high rate of change threshold can be used, specifically satisfying the following: (9) in, Let be the absolute value of the net power change at time t of the first new energy base. This is the threshold for sudden power change. Let be the absolute value of the net power change rate of the first new energy base at time t. The threshold for the sudden change in power rate can be taken as 8% of the rated power of the first new energy base, which is 6000MW, i.e., 480MW, in MW / s.

[0074] To address the gradual fluctuation characteristics of the second new energy base, a long window and low-change threshold can be used, specifically satisfying the following: (10) in, Let be the absolute value of the net power change of the second new energy base at time t. The threshold for gradual power change. Let be the absolute value of the net power change rate of the second new energy base at time t. The threshold for the gradual power change rate can be taken as 5% of the regional rated power of the second new energy base, which is 4500MW, i.e., 225MW, in MW / s.

[0075] Furthermore, since the power fluctuations at the First New Energy Base are mainly characterized by sudden drops / rises on a timescale of seconds and a high rate of change, the energy storage system requires fast detection, rapid response, high power, and short response time. The rated power of the energy storage at the First New Energy Base is 600MW, and the rated capacity is 2400MWh. Therefore, the energy storage at the First New Energy Base can adopt a dual-channel detection method, as follows: For the rate of change channel, when the following conditions are met Triggered immediately upon arrival; For the change channel, when the following conditions are met Triggered immediately upon arrival; If either of the two channels meets the triggering condition, the energy storage rapid response of the first new energy base will be activated.

[0076] Because the power fluctuations at the second new energy base are primarily characterized by gradual decay, with a timescale ranging from minutes to hours and a small rate of change, energy storage is required to provide smooth response, long-term support, and gradual decommissioning. The rated power of the energy storage at the second new energy base is 400MW, and the rated capacity is 1600MWh. Therefore, the energy storage at the second new energy base can adopt a sliding window integral detection method, as detailed below: (11) in, This represents the average power change. The duration of the sliding integral window. s, For any time within the integration period The instantaneous power change.

[0077] When satisfied At that time, the energy storage response of the second new energy base was triggered.

[0078] In practical applications, a 5-second sliding integral window can be used to smooth and average the instantaneous power changes in the region, filtering out transient noise such as short-term cloud cover and small power output fluctuations from wind turbines. This allows for the identification of only continuous, gradual power offsets, preventing malfunctions of energy storage under gradual change conditions. The time from determining the gradual disturbance to issuing the energy storage output control command does not exceed 500 milliseconds. This approach balances the smoothness of gradual fluctuations with timely compensation for long-term power offsets, stabilizing the overall power transmitted from the sending end and the converter bus voltage. This ensures a response to slow but continuous power changes while preventing false triggering due to normal fluctuations.

[0079] In one embodiment, based on power surge detection results, power change parameters, and fluctuation characteristic indicators, the energy storage response mode of each new energy base is determined for both sudden and gradual fluctuations, achieving differentiated SOC zoning management, specifically including: If the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is greater than the sudden change power change rate threshold, and the power change detection result is an effective sudden change disturbance, then the energy storage response mode is determined to be fast response type.

[0080] If the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is less than or equal to the preset gradual power change rate threshold, and the power change detection result is an effective gradual disturbance, then the energy storage response mode is determined to be continuous support type.

[0081] Verify the consistency between the power fluctuation type and the corresponding preset detection criteria and the energy storage response mode; otherwise, determine that the energy storage response mode is transitional.

[0082] Understandably, the rapid response type adapts to sudden disturbances, corresponding to a short detection window, millisecond-level instantaneous full-power support, and rapid exit after a short period of maintenance. The continuous support type adapts to gradual disturbances, corresponding to a long detection window, power ramp-up limiting, and long-term support of up to 4 hours. The matching consistency verification mainly checks whether the logic of the fluctuation type, detection criteria, and energy storage mode corresponds. The transition type refers to the fallback hybrid control mode when the fluctuation characteristics and disturbance conditions do not match.

[0083] Specifically, based on volatility characteristic indicators and the absolute value of the net power change rate The selection criteria for energy storage response modes can be defined as follows: (12) in, This serves as an identifier for the energy storage response mode of the new energy base. The threshold for fluctuation characteristics, This is the universal power change rate threshold under sudden disturbances. This is the universal power change rate threshold under gradual perturbation.

[0084] This embodiment achieves adaptive switching of energy storage strategies by jointly determining the energy storage control mode by integrating the inherent fluctuation attributes of the region and the real-time disturbance characteristics; by setting a transitional fallback mechanism, the risk of control failure caused by parameter mismatch can be avoided, thereby improving the robustness of system operation.

[0085] Furthermore, for the First New Energy Base, in the power command generation stage, the energy storage power command of the First New Energy Base can adopt an instantaneous full-power response mode, as follows: (13) in, The energy storage power command for the first new energy base at time t; The rated maximum charging and discharging power of the first energy storage control system can be taken as a value. MW; The state of charge (SOC) correction coefficient is based on the first energy storage control system. The closer the SOC is to the upper and lower limits, the smaller the value of this coefficient becomes. This refers to the triggering time of a sudden change disturbance; To determine the duration of continuous operation at full energy storage capacity, a value can be set to... s; The exit time constant can take the value of s; e are natural constants.

[0086] For the power direction, when the following conditions are met Under this power drop condition, the discharge at this time satisfies... When satisfied Under this power surge condition, charging at this time satisfies... .

[0087] In the differentiated SOC zoning management phase, the SOC operating range of the first-end new energy base meets the following requirements: (14) in, This is the real-time state of charge of the energy storage batteries at the First New Energy Base. This is the minimum charge limit allowed by the first energy storage control system. This is the maximum allowable charge limit for the first energy storage control system.

[0088] The aforementioned narrower range allows for sufficient charging and discharging space to accommodate sudden disturbances. The state of charge correction factor is: (15) when When needed, it can perform a lockout discharge and automatically switch to charging standby (energy storage standby) mode.

[0089] Meanwhile, for the second new energy base, a ramp-up limiting and long-term hold mode can be adopted in the power command generation stage, as follows: (16) in, The output power command for the continuous support energy storage at time t of the second new energy base; The rated maximum charging and discharging power of the second energy storage control system can be taken as a value. MW; This is the state-of-charge correction factor for the second energy storage control system; The energy storage output rise time constant is used to prevent sudden power surges from impacting the energy storage control system; it can be set to a value of [value missing]. s; This is a sign function used to determine the power direction; discharge occurs when power decreases and charging occurs when power increases.

[0090] In practical applications, the maximum continuous support time of the second new energy base h, which can fully utilize the 1600MWh capacity to cope with the gradual decay over a long period of time.

[0091] In the SOC zoning management and trend prediction phase, the energy storage SOC operating range of the second new energy base meets the following requirements: (17) in, This is the real-time state of charge of the energy storage batteries at the second new energy base. This is the minimum allowable charge level for the second energy storage control system. This is the maximum allowable charge limit for the second energy storage control system.

[0092] The aforementioned wider range allows for deep charge and discharge to cope with gradual decay over long periods. The specific state-of-charge correction factor is as follows: (18) Furthermore, future trends can be predicted based on power variation trends. The net power change within one hour is as follows: (19) in, This represents the predicted power change for the second new energy base. for The net power change rate of the second new energy base at any given time. To predict the time step.

[0093] If power is predicted to continue to decrease in the next hour and If the power is predicted to continue to rise, the discharge slope should be reduced in advance to avoid premature depletion of the state of charge (SOC). If so, reduce the charging slope in advance to avoid overcharging.

[0094] In one embodiment, based on the phase difference of power fluctuations, cross-regional energy storage coordination and mutual assistance control is executed according to a preset control strategy corresponding to each energy storage response mode, specifically including: If the power fluctuation phase difference between any two new energy bases is in phase or zero phase, the preset mutual assistance participation coefficient will be set to zero, and local mitigation strategies will be executed according to the energy storage response modes of the two new energy bases.

[0095] If the phase difference of the power fluctuations of any two new energy bases is out of phase, then the mutual assistance power, the additional power of reverse charging and discharging, and the tiered mutual assistance participation coefficient of the two new energy bases are determined respectively, and the local power command of energy storage is generated and issued to execute cross-regional energy storage coordination and mutual assistance control.

[0096] Among these, cross-regional mutual assistance should be prioritized lower than local fluctuation response. The degree of local fluctuation should be assessed, and cross-regional mutual assistance should not be participated in when there is a local emergency, but should be fully utilized for mutual assistance when local resources are sufficient.

[0097] It is understandable that the mutual assistance participation coefficient can be set to any value within the range of 0 to 1, which is used to control the output ratio of local energy storage participating in cross-regional mutual assistance; in-phase / zero-phase means that the power of the two bases rises or falls synchronously, and there is no fluctuation in a single region, with no complementary space; out-of-phase means that the power of one region rises and the power of another region falls, and there are conditions for power complementarity; local stabilization strategy means that energy storage is only used to offset the wind and solar power deficit or surplus in the local area and does not participate in cross-regional power allocation.

[0098] In practical applications, since the rated power of the energy storage at the first new energy base is different from that at the second new energy base, the mutual control needs to take into account the capacity difference between the two bases.

[0099] Specifically, in the fluctuation phase difference detection stage, it is necessary to define the direction of net power change between the two bases, as follows: (20) (twenty one) in, Let t be the power fluctuation direction indicator of the first new energy base at time t. The net power change rate of the first new energy base. Let be the power fluctuation direction indicator of the second new energy base at time t. The net power change rate of the second new energy base. For a symbolic function, satisfying: (twenty two) Furthermore, the wave phase difference satisfy: (twenty three) In the mutual assistance triggering and power distribution stage, when When the phase is reversed, cross-regional energy storage mutual assistance is triggered. At this time, the energy storage in the rising region is charged and the energy storage in the falling region is discharged, and the power complementarity is achieved by utilizing the regional fluctuation phase difference.

[0100] The calculation of mutual power needs to take into account the difference in rated power between the two parties, as detailed below: (twenty four) in, Let t be the cross-regional mutual assistance power limit between the two bases. Let be the available charging and discharging power of the first energy storage control system at time t. Let be the available charging and discharging power of the second energy storage control system at time t. The absolute value of the power fluctuation difference between the two bases represents the theoretically complementary power scale. This is the rated maximum discharge power of the first energy storage control system. This is the rated maximum discharge power of the second energy storage control system. Possible values MW is the upper limit of cross-regional power transfer to prevent excessive cross-regional power transfer from affecting local support.

[0101] The available charging and discharging power of the two bases can be specifically expressed as follows: (25) (26) in, This is the rated maximum charging power of the first energy storage control system. This is the state-of-charge correction factor for the first energy storage control system during the charging phase. This is the rated maximum charging power of the second energy storage control system. This is the state-of-charge correction coefficient for the second energy storage control system during the charging phase.

[0102] Furthermore, the power allocation for mutual assistance is as follows: (27) (28) in, The cross-regional mutual assistance power undertaken by the energy storage of the first new energy base at time t. The cross-regional mutual assistance power undertaken by the energy storage of the second new energy base at time t.

[0103] This means that while one zone is charging, the other zone is discharging, thus achieving power mutual assistance.

[0104] when When they are in phase, the fluctuations of the two bases are in the same direction, the mutual assistance coefficient is equal to 0, and each responds according to its local strategy.

[0105] In the mutual assistance priority and constraint setting stage, the priority of cross-regional mutual assistance is lower than that of local fluctuation response, specifically satisfying the following: (29) in, The total power command actually issued to the regional energy storage at time t. This provides the basic compensation power needed for local wind and solar energy fluctuations in the region. The power allocated to the region for cross-regional mutual assistance and compensation means that the energy storage output consists of two types of regulating power superimposed: first, to compensate for the wind and solar power gap of the base itself, and then to superimpose the weighted cross-regional complementary power to achieve integrated regulation of local voltage stabilization and regional coordinated mutual assistance. The mutual assistance participation coefficient can be specifically represented as follows: (30) Therefore, In the emergency condition of =0, the local power fluctuation exceeds 80% of the threshold, and the disturbance is strong. The entire energy storage capacity is used first to smooth the local gap, and the cross-regional mutual assistance component is directly set to zero to prevent the local voltage and external power transmission from running out of control due to sharing external mutual assistance.

[0106] Under the moderate disturbance condition of 0.5, local fluctuations range from 40% to 80% of the threshold. Half of the energy storage capacity is allocated to maintain local stability, while the other half participates in cross-regional complementarity, thus balancing local security and regional coordinated regulation.

[0107] Under the smooth operating condition of =1, local fluctuations are less than or equal to the threshold of 40%, local regulation pressure is small, and all surplus energy storage capacity is invested in cross-regional mutual assistance to maximize the utilization of the complementary characteristics of the opposite fluctuations between the two regions and reduce the overall energy storage charging and discharging losses.

[0108] In practical applications, the execution cycle of cross-regional mutual assistance control is... ms, synchronized with the PMU sampling period.

[0109] The different rated power of the energy storage at the first and second sending-end new energy bases determines the differences in their coordination with thermal power and DC systems.

[0110] Under sudden disturbances at the First New Energy Base, 600MW of energy storage can provide short-term high-power support. The specific rapid response sequence can be found in Table 1. In summary, thermal power starts up quickly, and energy storage provides power quickly in a short time.

[0111] Table 1. Rapid Response Sequence of the First New Energy Base

[0112] The start-up command for thermal power plants is: (31) in, The active power command for the thermal power units supporting the first new energy base at time t. The initial active power of the thermal power unit at the disturbance trigger time t0 is given. For the rapid ramping rate of thermal power units, MW / min, For indicator functions, satisfying When the condition is met, the function value is 1; when the condition is not met, the value is 0.

[0113] The DC current regulation circuit can be represented as: (32) in, This is the reference value for the DC current of the modulated LCC converter station. To adjust the gain coefficient, The voltage feedback term represents the deviation of the voltage at the sending-end converter bus. This is only used for fine-tuning current commands. Due to the drastic power fluctuations in the First New Energy Base, voltage deviations can reach 0.02~0.03 pu within 20ms, requiring a rapid response. Therefore, [the following is used:] It is 1.8. This is the original DC current command output by the upper-level power control system. It should follow the total power generation of the sending end. Change, satisfying: (33) in, This represents the actual total power generation capacity of wind, solar, thermal, and energy storage systems. This is the rated reference voltage on the DC side.

[0114] Under gradual disturbances, the 400MW energy storage at the second new energy base mainly provides long-term continuous support. The corresponding smooth response timing can be seen in Table 2 below, which can be summarized as delayed start-up of thermal power and slow deceleration of energy storage over a long period.

[0115] Table 2 Smooth Response Time Sequence of the Second New Energy Base

[0116] The conditions for starting up thermal power plants are met: (34) in, The signal indicating the start-up and commissioning of the thermal power units in the second new energy base is a Boolean identifier. This marks the initial identification moment of the gradual disturbance at the second new energy base; ΔP R2 (t) represents the power change after smoothing at the second new energy base; in this case, 30s is the threshold for the duration of the disturbance, and 100MW is the threshold for the continuous power imbalance.

[0117] Thermal power output command can be expressed as: (35) in, This refers to the active power command for the thermal power units supporting the second new energy base at time t. The initial active power of the thermal power unit at the disturbance trigger time t0 is given. The slow ramp-up rate of thermal power units. , The indicator function is the thermal power plant commissioning start-up indicator for the second new energy base. When the time is right, the function value is 1. When the time is right, the function value is 0.

[0118] The DC current regulation stage can still be represented by the above equations (32) and (33). Since the regional power change in the second new energy base is slow, the voltage deviation slowly forms to about 0.01 pu within a few seconds, which does not need to be too large, so it is taken as 0.01 pu. It is 0.4.

[0119] In the energy storage phase-out coordination phase, the rapid phase-out of energy storage (600MW) at the First New Energy Base was met: (36) in, This refers to the power command for the energy storage shutdown phase of the first new energy base at time t. This represents the energy storage output power at the moment the full-power maintenance phase of the first new energy base ends. To ensure the energy storage at full capacity can be maintained for an extended period of time at the first new energy base. For the exit time constant, s, ensuring that the energy storage is completely deactivated within approximately 120 seconds.

[0120] The gradual phase-out of energy storage (400MW) at the second-end renewable energy base is sufficient: (37) in, This refers to the power command for the energy storage shutdown phase of the second new energy base at time t. This serves as the baseline value for stable energy storage output at the moment of gradual disturbance triggering. The linear withdrawal rate of energy storage for the second new energy base. MW / s, The exit start time is when the actual output of thermal power reaches 90% of the current supporting power of energy storage.

[0121] Timing coordination constraints are satisfied: Power balance constraints: ; Energy storage SOC constraints: ; Energy storage power constraints: MW, MW; Thermal power plant ramping constraints: ; DC regulation rate constraint: .

[0122] To verify the effectiveness of the proposed differentiated energy storage control strategy, the following two typical operating conditions were set up for simulation verification.

[0123] Under the typical operating condition of a sudden drop in photovoltaic output, at t=5.0s, due to a sudden and rapid cloud cover, the photovoltaic output of the First New Energy Base plummeted from 1200MW to 400MW within 0.3s, a decrease of 800MW. The net power change at the First New Energy Base is shown in the figure. MW> MW, rate of change MW / s> MW / s, triggering sudden change detection.

[0124] The control process is as follows: The first step was that the PMU detected the first new energy base. The power fluctuation type is determined to be a sudden change type fluctuation.

[0125] The second step is to select the rapid response mode for energy storage and activate the 600MW rapid response energy storage system at the first new energy base.

[0126] Thirdly, the energy storage system at the first new energy base implements fast-response control with a response delay of ≤20ms; full-power discharge. MW, meaning MW; s, s; The fourth step was the detection of the second new energy base. The wind power output of the second new energy base decreased from 1000MW to 900MW, declining in the same direction as the first new energy base. , This will not trigger cross-regional mutual assistance.

[0127] Fifth, the thermal power unit receives the start-up preparation signal within 20ms and proceeds according to the instructions. Start climbing at MW / min.

[0128] Figure 3 The coordinated control effect was demonstrated in the first region under a sudden change in photovoltaic power generation scenario. Figure 3 In (a), the photovoltaic power exhibits a typical sharp drop, with a decrease of 800MW, far exceeding the detection threshold of 480MW. Figure 3In (b), the first energy storage area responds instantaneously within 20ms, discharging at full power of 600MW (accounting for 75% of the deficit), releasing 150MW (18.75%) of wind power reserve, and the thermal power unit starts up and ramps up synchronously at 15MW / min, gradually taking over during the 90s full power maintenance period of the energy storage. Figure 3 (c) The DC transmission power drop is controlled within 30MW. Figure 3 (d) The minimum value of the converter bus voltage is not lower than 0.97 pu, and it recovers to the rated value within 0.8 s. This result shows that the fast-response energy storage control strategy proposed in this invention can achieve millisecond-level full-power support under sudden disturbances, effectively suppressing DC power drop and converter bus voltage instability.

[0129] Under the typical operating condition of a sudden increase in wind power output, at t=6.0s, the wind speed suddenly increases, and the wind power output of the second new energy base rapidly rises from 1000MW to 1550MW. The rated power is 2200MW, the increase is 550MW, which exceeds the threshold of 220MW.

[0130] The control process is as follows: The first step was that the PMU detected the second new energy base. ,and The power fluctuation type is determined to be gradual fluctuation (MW / s).

[0131] The second step, MW> MW triggers power surge detection, satisfying the gradual triggering condition.

[0132] The third step, and Energy storage response mode selection criterion output =Continuous support type, and the mode identifier will be issued to the energy storage controller of the second new energy base.

[0133] Fourth, the detection window duration is set to 5 seconds, and the response delay is ≤500ms; MW, =5s (power ramp-up) = 4h.

[0134] Fifth step, the first new energy base was detected. The wind power output of the first new energy base increased from 3,000 MW to 3,200 MW, with the two regions showing opposite trends (the second region decreased while the first region increased). This triggers cross-regional mutual assistance: MW, MW; ; The maximum power capacity for mutual assistance is 80MW. ); The first new energy base has 80MW of energy storage and charging capacity to absorb the surplus of the first new energy base, and the energy storage of the second new energy base will receive an additional 80MW of mutual discharge power. The total energy storage capacity of the second new energy base is 400MW (local) + 80MW (mutual aid) = 480MW.

[0135] Step 6: The thermal power plant will start after a 30-second delay. ,by MW / min climbing.

[0136] Figure 4 The demonstration showcased the coordinated control effect of cross-regional mutual assistance under a gradual wind power attenuation scenario at the Second New Energy Base. During the period from t=8 to 13s, the wind turbines at the Second New Energy Base slowly attenuated by 500MW (1200MW→700MW) within 5s. After the system identified this as a gradual disturbance, it triggered the continuous energy storage support mode of the Second New Energy Base. Figure 4 (a) The output of wind power in China exhibits a typical gradual decay characteristic. Figure 4 (b) In this case, the energy storage at the second new energy base will be τ after the 5-second detection window. rise The discharge power was slowly increased to 400MW (80% of the deficit) with a slope of 5s, avoiding stress damage to the energy storage control system caused by the power surge; at the same time, it was detected that the wind power of the first new energy base was in the rising period, and 80MW (16%) was transferred to the second new energy base through inter-regional mutual assistance, so that the total supporting power reached 480MW; the thermal power unit started with a delay of 30s (at 38s), and slowly climbed up at 12MW / min to take over the remaining power. Figure 4 (c) The DC transmission power drop is controlled within 20MW. Figure 4 (d) The minimum converter bus voltage is not lower than 0.99 pu. This result shows that the continuous support energy storage control strategy proposed in this invention, combined with the inter-regional mutual assistance mechanism, can achieve smooth power support under gradual disturbances, while avoiding frequent adjustments by delaying the start-up of thermal power plants, effectively improving the system's operating economy and equipment lifespan.

[0137] Corresponding to the above method embodiments, this specification also provides an embodiment of an ultra-high voltage direct current sending-end energy storage regulation device under differentiated wind and solar power fluctuations. Figure 5 This specification illustrates a schematic diagram of an ultra-high voltage direct current (UHVDC) transmission-end energy storage and control device under differentiated wind and solar power fluctuations, according to one embodiment of this specification. Figure 5 As shown, the device includes: The acquisition module 210 is used to acquire power timing data of each new energy base at the UHVDC transmission end, including wind, solar, thermal, and energy storage. The calculation module 220 is used to calculate the power change parameters and fluctuation characteristic indicators of each new energy base based on the power time series data, and to determine the power fluctuation type of each new energy base. The detection module 230 is used to perform power mutation detection according to the preset detection criteria corresponding to each power fluctuation type, and to determine the energy storage response mode of each new energy base based on the power mutation detection results, power change parameters and fluctuation characteristic indicators, so as to realize differentiated SOC zoning management for the two types of fluctuations: sudden change and gradual change. The control module 240 is used to determine the power fluctuation phase difference of each new energy base, and based on the power fluctuation phase difference, execute cross-regional energy storage coordination and mutual assistance control according to the preset control strategy corresponding to each energy storage response mode, and execute wind, solar, thermal and energy storage differentiated timing control.

[0138] In one possible implementation, the calculation module 220 is specifically used to: perform moving average filtering on the power time series data using a sliding window of a preset length to obtain filtered power time series data; perform time-by-time differentiation on the filtered power time series data to obtain the net power change rate of each new energy base; calculate the power difference between the current time and the previous time of the set time interval based on the filtered power time series data to obtain the net power change of each new energy base; and use the net power change rate and net power change as power change parameters of each new energy base.

[0139] In one possible implementation, the calculation module 220 is specifically used to: retrieve pre-stored historical operation correlation data of each new energy base, and extract time series samples of net power change rate within a continuously set time period from the historical operation correlation data; determine the sample standard deviation of power change rate and the sample mean of absolute value of power change rate for each new energy base based on the time series samples of net power change rate; and calculate the fluctuation characteristic index of each new energy base by dividing the sample standard deviation of power change rate by the sample mean of absolute value of power change rate.

[0140] In one possible implementation, the calculation module 220 is specifically used to: determine the fluctuation characteristic threshold of each new energy base based on historical operational correlation data through a combination of offline training and online updating; compare the fluctuation characteristic index of each new energy base with the corresponding fluctuation characteristic threshold; if the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, then the power fluctuation type of the current new energy base is determined to be a sudden change fluctuation; if the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, then the power fluctuation type of the current sending-end new energy base is determined to be a gradual change fluctuation.

[0141] In one possible implementation, the detection module 230 is specifically used to: if the power fluctuation type is a sudden change fluctuation, determine whether the absolute value of the net power change exceeds a preset sudden change power change threshold to obtain a first judgment result, and determine whether the absolute value of the net power change rate exceeds a preset sudden change power change rate threshold to obtain a second judgment result; if the first judgment result and / or the second judgment result are yes, the power change detection result is that a valid sudden change disturbance has occurred; if the power fluctuation type is a gradual change fluctuation, determine the average power change of each new energy base using a sliding window integral detection method, and determine whether the absolute value of the average power change exceeds a preset gradual change power change threshold to obtain a third judgment result; if the third judgment result is yes, the power change detection result is that a valid gradual change disturbance has occurred.

[0142] In one possible implementation, the detection module 230 is specifically used to: determine the energy storage response mode as a rapid response mode if the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is greater than the sudden change power change rate threshold, and the power change detection result is an effective sudden change disturbance; if the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is less than or equal to the preset gradual change power change rate threshold, and the power change detection result is an effective gradual change disturbance; and verify the consistency between the power fluctuation type and the corresponding preset detection criteria and the energy storage response mode. Otherwise, the energy storage response mode is determined to be a transition mode.

[0143] In one possible implementation, the control module 240 is specifically used to: if the phase difference of the power fluctuations of any two new energy bases is in phase or zero phase, then set the preset mutual assistance participation coefficient to zero, and execute the local mitigation strategy according to the energy storage response mode of each of the two new energy bases; if the phase difference of the power fluctuations of any two new energy bases is out of phase, then determine the mutual assistance power, reverse charging and discharging additional power, and tiered mutual assistance participation coefficient of the two new energy bases respectively, generate and issue local energy storage power commands to execute cross-regional energy storage coordination and mutual assistance control; wherein, the priority of cross-regional mutual assistance should be lower than that of local fluctuation response, judge the degree of local fluctuation, and not participate in cross-regional mutual assistance when local is in emergency, and fully assist when local is sufficient.

[0144] The above is a schematic scheme of an ultra-high voltage direct current (UHVDC) transmission-end energy storage regulation device under differentiated wind and solar power fluctuations according to this embodiment. It should be noted that the technical solution of this UHVDC transmission-end energy storage regulation device under differentiated wind and solar power fluctuations belongs to the same concept as the technical solution of the aforementioned UHVDC transmission-end energy storage regulation method under differentiated wind and solar power fluctuations. Details not described in detail in the technical solution of the UHVDC transmission-end energy storage regulation device under differentiated wind and solar power fluctuations can be found in the description of the technical solution of the aforementioned UHVDC transmission-end energy storage regulation method under differentiated wind and solar power fluctuations.

[0145] Figure 6 A structural block diagram of a computing device 300 according to one embodiment of this specification is shown. The components of the computing device 300 include, but are not limited to, a memory 310 and a processor 320. The processor 320 is connected to the memory 310 via a bus 330, and a database 350 is used to store data.

[0146] The computing device 300 also includes an access device 340, which enables the computing device 300 to communicate via one or more networks 360. Examples of these networks include Public Switched Telephone Network (PSTN), Local Area Network (LAN), Wide Area Network (WAN), Personal Area Network (PAN), or combinations of communication networks such as the Internet. The access device 340 may include one or more of any type of wired or wireless network interface (e.g., a network interface card (NIC)), such as an IEEE 802.11 Wireless Local Area Network (WLAN) wireless interface, a Wi-MAX (Worldwide Interoperability for Microwave Access) interface, an Ethernet interface, a Universal Serial Bus (USB) interface, a cellular network interface, a Bluetooth interface, or a Near Field Communication (NFC) interface.

[0147] In one embodiment of this specification, the aforementioned components of the computing device 300 and Figure 6 Other components, not shown, can also be connected to each other, for example, via a bus. It should be understood that... Figure 6The block diagram of the computing device shown is for illustrative purposes only and is not intended to limit the scope of this specification. Those skilled in the art can add or replace other components as needed.

[0148] The computing device 300 can be any type of stationary or mobile computing device, including mobile computers or mobile computing devices (e.g., tablet computers, personal digital assistants, laptop computers, notebook computers, netbooks, etc.), mobile phones (e.g., smartphones), wearable computing devices (e.g., smartwatches, smart glasses, etc.) or other types of mobile devices, or stationary computing devices such as desktop computers or personal computers (PCs). The computing device 300 can also be a mobile or stationary server.

[0149] The processor 320 executes the following computer-executable instructions, which, when executed by the processor, implement the steps of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations. The above is a schematic representation of a computing device according to this embodiment. It should be noted that the technical solution of this computing device and the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations belong to the same concept. Details not described in detail in the technical solution of the computing device can be found in the description of the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations.

[0150] An embodiment of this specification also provides a computer-readable storage medium storing computer-executable instructions that, when executed by a processor, implement the steps of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations.

[0151] The above is an illustrative scheme of a computer-readable storage medium according to this embodiment. It should be noted that the technical solution of this storage medium belongs to the same concept as the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations. For details not described in detail in the technical solution of the storage medium, please refer to the description of the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations.

[0152] An embodiment of this specification also provides a computer program, wherein when the computer program is executed in a computer, the computer is instructed to perform the steps of the above-described method for regulating the energy storage at the transmission end of ultra-high voltage direct current under differentiated wind and solar power fluctuations.

[0153] The above is an illustrative scheme of a computer program according to this embodiment. It should be noted that the technical solution of this computer program and the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations belong to the same concept. For details not described in detail in the technical solution of the computer program, please refer to the description of the technical solution of the above-described method for regulating energy storage at the UHVDC transmission end under differentiated wind and solar power fluctuations.

[0154] The foregoing has described specific embodiments of this specification. Other embodiments are within the scope of the appended claims. In some cases, the actions or steps recited in the claims may be performed in a different order than that shown in the embodiments and may still achieve the desired result. Furthermore, the processes depicted in the drawings do not necessarily require the specific or sequential order shown to achieve the desired result. In some embodiments, multitasking and parallel processing are possible or may be advantageous.

[0155] The computer instructions include computer program code, which may be in the form of source code, object code, executable file, or certain intermediate forms. The computer-readable medium may include any entity or device capable of carrying the computer program code, recording media, USB flash drives, portable hard drives, magnetic disks, optical disks, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signals, telecommunication signals, and software distribution media, etc. It should be noted that the content included in the computer-readable medium may be appropriately added to or subtracted according to the requirements of legislation and patent practice in the jurisdiction. For example, in some jurisdictions, according to legislation and patent practice, computer-readable media may not include electrical carrier signals and telecommunication signals.

[0156] It should be noted that, for the sake of simplicity, the foregoing method embodiments are all described as a series of actions. However, those skilled in the art should understand that the embodiments in this specification are not limited to the described order of actions, because according to the embodiments in this specification, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in this specification are all preferred embodiments, and the actions and modules involved are not necessarily essential to the embodiments in this specification.

[0157] In the above embodiments, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0158] The preferred embodiments disclosed above are merely illustrative of this specification. The optional embodiments do not exhaustively describe all details, nor do they limit the invention to the specific implementations described. Clearly, many modifications and variations can be made based on the embodiments described herein. These embodiments are selected and specifically described in this specification to better explain the principles and practical applications of the embodiments, thereby enabling those skilled in the art to better understand and utilize this specification. This specification is limited only by the claims and their full scope and equivalents.

Claims

1. A method for regulating energy storage at the sending end of an ultra-high voltage direct current (UHVDC) transmission line under differentiated wind and solar power fluctuations, characterized in that, include: Acquire power timing data of each new energy base at the UHVDC transmission end, including wind, solar, thermal, and energy storage systems. Based on the power time series data, the power change parameters and fluctuation characteristic indicators of each new energy base are calculated, and the power fluctuation type of each new energy base is determined. Power mutation detection is performed according to the preset detection criteria corresponding to each power fluctuation type. Based on the power mutation detection results, the power change parameters, and the fluctuation characteristic indicators, the energy storage response mode of each new energy base is determined for the two types of fluctuations, namely sudden change and gradual change, so as to realize differentiated SOC zoning management. The phase difference of power fluctuation in each new energy base is determined. Based on the phase difference of power fluctuation, cross-regional energy storage coordination and mutual assistance control is performed according to the preset control strategy corresponding to each energy storage response mode, and wind, solar, thermal and energy storage differentiated timing control is performed.

2. The method according to claim 1, characterized in that, Based on the aforementioned power time-series data, the power variation parameters of each new energy base are calculated, including: A sliding window of preset length is used to perform a moving average filtering process on the power time series data to obtain filtered power time series data; The net power change rate of each new energy base is obtained by performing time-by-time differentiation on the filtered power time-series data. Based on the filtered power time-series data, the power difference between the current moment and the previous moment of the set time interval is calculated to obtain the net power change of each new energy base. The net power change rate and the net power change amount are used as power change parameters for each new energy base.

3. The method according to claim 2, characterized in that, Calculate the fluctuation characteristic indicators of each new energy base, including: Retrieve pre-stored historical operation correlation data of each new energy base, and extract time series samples of net power change rate within a continuous set time period from the historical operation correlation data; Based on the aforementioned net power change rate time series sample, the sample standard deviation of the power change rate and the sample mean of the absolute value of the power change rate for each new energy base are determined respectively. The fluctuation characteristic index of each new energy base is obtained by dividing the standard deviation of the power change rate sample by the mean of the absolute value of the power change rate sample.

4. The method according to claim 3, characterized in that, Determine the power fluctuation types of each new energy base, including: Based on the historical operational data, the fluctuation characteristic thresholds of each new energy base are determined through a combination of offline training and online updates. The fluctuation characteristic index of each new energy base is compared with the corresponding fluctuation characteristic threshold. If the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the power fluctuation type of the current new energy base is determined to be a sudden change fluctuation. If the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the power fluctuation type of the current sending-end new energy base is determined to be a gradual change fluctuation.

5. The method according to claim 4, characterized in that, Power fluctuation detection is performed according to the preset detection criteria corresponding to each of the power fluctuation types, including: If the power fluctuation type is a sudden change fluctuation, then determine whether the absolute value of the net power change exceeds a preset sudden change power change threshold to obtain a first judgment result, and determine whether the absolute value of the net power change rate exceeds a preset sudden change power change rate threshold to obtain a second judgment result. If the first judgment result and / or the second judgment result are yes, then the power change detection result is that a valid sudden change disturbance has occurred. If the power fluctuation type is a gradual fluctuation, the average power change of each new energy base is determined by the sliding window integral detection method, and it is determined whether the absolute value of the average power change exceeds the preset gradual power change threshold to obtain a third judgment result. If the third judgment result is yes, the power change detection result is that a valid gradual disturbance has occurred.

6. The method according to claim 5, characterized in that, Based on the power surge detection results, the power change parameters, and the fluctuation characteristic indicators, the energy storage response mode for each new energy base is determined for both sudden and gradual fluctuations, achieving differentiated SOC zoning management, including: If the fluctuation characteristic index is greater than the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is greater than the sudden change power change rate threshold, and the power change detection result is that an effective sudden change disturbance has occurred, then the energy storage response mode is determined to be a fast response type. If the fluctuation characteristic index is less than or equal to the corresponding fluctuation characteristic threshold, the absolute value of the net power change rate is less than or equal to the preset gradual power change rate threshold, and the power mutation detection result is that an effective gradual disturbance has occurred, then the energy storage response mode is determined to be continuous support type. Verify the consistency between the power fluctuation type and the corresponding preset detection criterion and the energy storage response mode; otherwise, determine that the energy storage response mode is transitional.

7. The method according to claim 1, characterized in that, Based on the power fluctuation phase difference, cross-regional energy storage coordination and mutual assistance control is executed according to the preset control strategy corresponding to each of the energy storage response modes, including: If the phase difference of the power fluctuations of any two new energy bases is in phase or zero phase, the preset mutual assistance participation coefficient will be set to zero, and local mitigation strategies will be executed according to the energy storage response modes of the two new energy bases respectively. If the phase difference of the power fluctuations of any two new energy bases is out of phase, then the mutual assistance power, the additional power of reverse charging and discharging, and the tiered mutual assistance participation coefficient of the two new energy bases are determined respectively, and the local power command of energy storage is generated and issued to execute cross-regional energy storage coordination and mutual assistance control. Among these, cross-regional mutual assistance should be prioritized lower than local fluctuation response. The degree of local fluctuation should be assessed, and cross-regional mutual assistance should not be participated in when there is a local emergency, but should be fully utilized for mutual assistance when local resources are sufficient.

8. A UHVDC transmitting-end energy storage and regulation device under differentiated wind and solar power fluctuations, characterized in that, include: The acquisition module is used to acquire power timing data of various new energy bases at the UHVDC transmission end, including wind, solar, thermal, and energy storage systems. The calculation module is used to calculate the power change parameters and fluctuation characteristic indicators of each new energy base based on the power time series data, and to determine the power fluctuation type of each new energy base. The detection module is used to perform power mutation detection according to the preset detection criteria corresponding to each power fluctuation type, and to determine the energy storage response mode of each new energy base for the two types of fluctuations, namely sudden change and gradual change, based on the power mutation detection results, the power change parameters and the fluctuation characteristic indicators, so as to realize differentiated SOC zoning management. The control module is used to determine the power fluctuation phase difference of each new energy base, and based on the power fluctuation phase difference, execute cross-regional energy storage coordination and mutual assistance control according to the preset regulation strategy corresponding to each energy storage response mode, and execute wind, solar, thermal and energy storage differentiated timing control.

9. A computing device, characterized in that, include: Memory and processor; The memory is used to store computer-executable instructions, and the processor is used to execute the computer-executable instructions. When the computer-executable instructions are executed by the processor, they implement the steps of the UHVDC transmission-end energy storage regulation method under differentiated wind and solar power fluctuations as described in any one of claims 1 to 7.

10. A computer-readable storage medium storing computer-executable instructions, characterized in that, When the computer-executable instructions are executed by the processor, they implement the steps of the UHVDC transmission-end energy storage regulation method under differentiated wind and solar power fluctuations as described in any one of claims 1 to 7.

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