Distributed photovoltaic power output control methods, devices, equipment, media and program products

Abstract

This application relates to a method, apparatus, equipment, medium, and program product for controlling distributed photovoltaic (PV) output. It includes: collecting operational status data of the distribution area and distributed PV access points within the current time window; calculating the safety budget value of the distribution area within the next time window; applying consistency constraints to the safety budget value to obtain the final safety budget value; obtaining a final predicted safety margin for a preset future time range based on historical operational status data sequences; determining safety control parameters based on the relationship between the final predicted safety margin and a preset safety margin threshold; and generating control commands based on preset safety budget allocation rules, the final safety budget value, the safety control parameters, and the final predicted safety margin, instructing the distribution area-side terminal to control the output of the distributed PV units within the distribution area based on the control commands. This method enables timely control of distributed PV output.

Description

Technical Field

[0001] This application relates to the field of power system distribution network operation control technology, and in particular to a distributed photovoltaic power output control method, device, computer equipment, computer-readable storage medium and computer program product. Background Technology

[0002] With the large-scale integration of distributed photovoltaic (PV) systems into low-voltage distribution networks and transformer substations, problems such as reverse power transmission from substations, reverse overload of transformers, voltage exceeding limits, and decreased operational stability are prone to occur during low-load periods. These issues have become one of the important factors affecting the safe operation of distribution networks.

[0003] In existing technologies, common practices for addressing the risks of voltage exceeding limits and reverse overload in transformer substations include fixed threshold power limiting, inverter local protection activation, selection of fixed control quantities based on voltage ranges (such as fixed active power reduction or fixed reactive power support / absorption), and manual intervention.

[0004] However, current methods or traditional approaches rely solely on current measurements for triggering, which can easily lead to lag and oscillations in the control of distributed photovoltaic power output. Summary of the Invention

[0005] Therefore, it is necessary to provide a distributed photovoltaic power output control method, device, computer equipment, computer-readable storage medium, and computer program product that can control the distributed photovoltaic power output in a timely manner, in response to the above-mentioned technical problems.

[0006] Firstly, this application provides a distributed photovoltaic power output control method, applied to a master station control unit, comprising:

[0007] Collect the current time window's operating status data for the transformer substation and distributed photovoltaic access points;

[0008] Based on the operating status data and preset thresholds, the safety budget value of the transformer area in the next time window is calculated. The safety budget value is used to limit the operating status data of the transformer area in the next time window.

[0009] Based on the maximum rate of change between adjacent windows, the safety budget value of the transformer area in the next time window is subjected to consistency constraint processing to obtain the final safety budget value of the next time window.

[0010] Based on the historical operating status data sequence, an initial predicted safety margin for a preset future time range is obtained, and based on the initial predicted safety margin, a final predicted safety margin is obtained; wherein, the final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value.

[0011] Based on the relationship between the final predicted safety margin and the preset safety margin threshold, the operation control mode is obtained, and the safety control parameters are determined based on the operation control mode.

[0012] Based on the preset safety budget allocation rules, the final safety budget value, safety control parameters, and the final predicted safety margin, control commands are generated and sent to the distribution area terminal to instruct the distribution area terminal to control the output of the distributed photovoltaic units in the distribution area based on the control commands.

[0013] Secondly, this application also provides a distributed photovoltaic power output control method, applied to a distributed photovoltaic terminal, including:

[0014] The system acquires control commands sent by the distribution area terminal. These commands include safety budget allocation rules, final safety budget values, safety control parameters, final predicted safety margin, and reference output limits for each distributed photovoltaic unit.

[0015] Based on the estimated available output of each distributed photovoltaic unit at the current moment and the upper limit of the reference output of each distributed photovoltaic unit, the reference output command of each distributed photovoltaic unit is obtained.

[0016] Based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin, the actual output of each distributed photovoltaic unit is generated.

[0017] Thirdly, this application also provides a distributed photovoltaic power output control system, including a master station control unit, a transformer substation side terminal, and a distributed photovoltaic terminal; the master station control unit, the transformer substation side terminal, and the distributed photovoltaic terminal are connected through a communication network; the transformer substation side terminal is used to receive control commands sent by the master station control unit and send the control commands to the distributed photovoltaic terminal;

[0018] The main station control unit is used to implement the steps of the method in the first aspect;

[0019] The transformer substation terminal is used to receive control commands sent by the main station control unit and send the control commands to the distributed photovoltaic terminal.

[0020] Distributed photovoltaic terminal, used to implement the steps of the second aspect of the method.

[0021] Fourthly, this application also provides a distributed photovoltaic power output control device, applied to the main station control unit, comprising:

[0022] The data acquisition module is used to collect the operating status data of the transformer substation and distributed photovoltaic access points within the current time window;

[0023] The calculation module is used to calculate the safety budget value of the transformer area in the next time window based on the operating status data and the preset threshold. The safety budget value is used to limit the operating status data of the transformer area in the next time window.

[0024] The first obtaining module is used to perform consistency constraint processing on the safety budget value of the transformer area in the next time window based on the maximum change rate between preset adjacent windows, so as to obtain the final safety budget value of the next time window.

[0025] The second obtaining module is used to obtain an initial predicted safety margin for a preset future time range based on the historical operating status data sequence, and to obtain a final predicted safety margin based on the initial predicted safety margin; wherein, the final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value.

[0026] The third module is used to obtain the operation control mode based on the relationship between the final predicted safety margin and the preset safety margin threshold, and to determine the safety control parameters based on the operation control mode.

[0027] The first generation module is used to generate control commands based on the preset safety budget allocation rules, the final safety budget value, safety control parameters, and the final predicted safety margin, and send the control commands to the distribution terminal in the distribution area to instruct the distribution terminal to control the output of the distributed photovoltaic units in the distribution area based on the control commands.

[0028] Fifthly, this application also provides a distributed photovoltaic power output control device, applied to a distributed photovoltaic terminal, comprising:

[0029] The acquisition module is used to acquire control commands sent by the transformer substation side terminal. The control commands include safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit of each distributed photovoltaic unit.

[0030] The fourth module is used to obtain the reference output command of each distributed photovoltaic unit based on the estimated available output of each distributed photovoltaic unit at the current moment and the reference output limit of each distributed photovoltaic unit.

[0031] The second generation module is used to generate the actual output of each distributed photovoltaic unit based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin.

[0032] Sixthly, this application also provides a computer device, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to perform the above steps.

[0033] In a seventh aspect, this application also provides a computer-readable storage medium having a computer program stored thereon, which, when executed by a processor, performs the steps described above.

[0034] Eighthly, this application also provides a computer program product, including a computer program that, when executed by a processor, performs the above steps.

[0035] The aforementioned distributed photovoltaic (PV) output control method, device, computer equipment, computer-readable storage medium, and computer program product collect operating status data of the transformer substation and distributed PV access points within the current time window; calculate the substation safety budget value for the next time window based on the operating status data and a preset threshold, wherein the safety budget value is used to limit the operating status data of the substation within the next time window; perform consistency constraint processing on the substation safety budget value for the next time window according to the maximum rate of change between preset adjacent windows to obtain the final safety budget value for the next time window; obtain an initial predicted safety margin for a preset future time range based on the historical operating status data sequence, and obtain a final predicted safety margin based on the initial predicted safety margin; wherein the final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value; and based on the maximum rate of change between preset adjacent windows, perform consistency constraint processing on the substation safety budget value for the next time window to obtain the final safety budget value for the next time window; obtain an initial predicted safety margin for a preset future time range based on the historical operating status data sequence, and obtain a final predicted safety margin based on the initial predicted safety margin; and obtain a final predicted safety margin based on the maximum rate of change between preset adjacent windows. The relationship between the final predicted safety margin and the preset safety margin threshold is used to obtain the operation control mode, and safety control parameters are determined based on the operation control mode. Control commands are generated based on the preset safety budget allocation rules, the final safety budget value, safety control parameters, and the final predicted safety margin, and sent to the distribution area terminal to instruct the terminal to control the output of distributed photovoltaic units in the distribution area. Based on the current time window's operating status data and the preset threshold, the safety budget value for the next time window is calculated continuously, defining a clear safety boundary for the distribution area's operation and limiting the fluctuation range of operating status data from the source. Consistency constraints based on the maximum rate of change of adjacent windows are used to avoid sudden changes in the safety budget, ensuring the rationality and stability of the budget value, preventing control misjudgments caused by budget fluctuations, and reducing instantaneous risks. By extrapolating the safety margin for future time ranges based on historical operating status data sequences, forward contraction or release operations are performed on the final safety budget value using the final predicted safety margin, achieving early risk prediction and proactive control. This technical solution constructs a full-process, refined, and adaptive distributed photovoltaic safety control system for power distribution areas through rolling calculation and allocation of safety budgets at the power distribution area level, forward-looking regulation based on margin trend prediction, and online correction at the terminal side. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application or related technologies, the drawings used in the description of the embodiments of this application or related technologies will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this application. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 This is an application environment diagram of a distributed photovoltaic power output control method in one embodiment;

[0038] Figure 2 This is a flowchart illustrating a distributed photovoltaic power output control method applied to the master station control unit in one embodiment;

[0039] Figure 3 This is a flowchart illustrating a distributed photovoltaic output control method applied to a distributed photovoltaic terminal in one embodiment.

[0040] Figure 4 This is a schematic diagram of a distributed photovoltaic power output control system in one embodiment;

[0041] Figure 5 This is a structural block diagram of a distributed photovoltaic power output control device applied to the master station control unit in one embodiment;

[0042] Figure 6 This is a structural block diagram of a distributed photovoltaic power output control device applied to a distributed photovoltaic terminal in one embodiment;

[0043] Figure 7 This is an internal structural diagram of a computer device in one embodiment. Detailed Implementation

[0044] To make the objectives, technical solutions, and advantages of this application clearer, the following detailed description is provided in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this application.

[0045] As described in the background section, the methods of related technologies have the following problems: The control strategy is crude and the response is lagging: relying on threshold triggering or fixed strategy switching easily leads to "frequent triggering / exit" or "excessive power rationing," resulting in severe photovoltaic power curtailment; centralized optimization is difficult to implement without an accurate model; if there is communication delay or measurement error, commands may become infeasible and exceed limits; there is a lack of a runtime constraint maintenance mechanism that can verify the feasibility of control commands and make online corrections under uncertain conditions, making it difficult to guarantee that key indicators do not exceed limits under any operating state; under the combined effect of multiple photovoltaic households, single-point / single-machine strategies cannot balance fairness and overall operational constraints, easily leading to unbalanced control; the inventors' research found that the reason for these problems lies in the over-reliance on grid topology and line parameters, and the centralized optimization control method based on the computational model is difficult to deploy in engineering or has high maintenance costs.

[0046] For the reasons mentioned above, this application provides a distributed photovoltaic power output control method, which aims to address the above problems.

[0047] The main station control unit is used to receive the operating status data of the distribution area, calculate the safety budget value of the distribution area, perform multi-time scale margin trend prediction, configure the operation control mode and safety control parameters, issue safety budget, allocation rules, parameters and rollback strategies, and perform consistency verification and convergence correction based on feedback from the distribution area side terminals.

[0048] Distribution area terminal: Used to collect / aggregate operating status data such as voltage, current, and power of the distribution area and send it to the main station control unit; receive safety budgets and allocation rules issued by the main station control unit; perform local coordination and allocation of connected distributed photovoltaic units, generate reference output limits for each distributed photovoltaic unit and issue them to each distributed photovoltaic unit. A distribution area is a dedicated power supply area centered on a distribution transformer, starting from the low-voltage side outgoing line of the transformer and extending to all electrical loads, distributed photovoltaic access points, distribution lines, metering devices, etc. within the power supply range of the transformer. The distribution area terminal is a smart sensing and execution device specifically deployed for its respective distribution area. The two have a one-to-one subordinate relationship. The distribution area terminal exists dependent on the distribution area, and all its functions revolve around the operation and management of the distribution area.

[0049] The distributed photovoltaic terminal includes an inverter and its control module, which are used to: receive the reference output limit sent by the terminal on the distribution area side; generate the reference output command; perform runtime safety filtering based on real-time measurement and predicted risk in each control cycle, output the actual output; and send the actual output and the limit control status.

[0050] Time window: The period during which the main station control unit calculates and issues the update of the security budget value, denoted as . For example, it can be 30s, 60s or 300s.

[0051] Control cycle: The cycle in which the distributed photovoltaic terminal executes safety filtering during operation. Safety filtering is equivalent to obtaining the actual output power based on the filtering intensity coefficient. The control cycle can be denoted as: It can be 100ms, 200ms, or 1s, usually. .

[0052] The distributed photovoltaic power output control method provided in this application embodiment can be applied to, for example... Figure 1 The application environment shown includes a master station control unit 101, a transformer substation terminal 102, and a distributed photovoltaic terminal 103. The master station control unit 101 collects the operating status data of the transformer substation and distributed photovoltaic access points within the current time window. Based on the operating status data and a preset threshold, the master station control unit 101 calculates the safety budget value for the transformer substation within the next time window, where the safety budget value is used to limit the operating status data of the transformer substation within the next time window. The master station control unit 101 performs consistency constraint processing on the safety budget value of the transformer substation within the next time window according to the maximum rate of change between preset adjacent windows, obtaining the final safety budget value for the next time window. Based on the historical operating status data sequence, the master station control unit 101 obtains the initial predicted safety margin for a preset future time range, and based on the initial predicted safety margin... The safety margin is measured to obtain the final predicted safety margin; the final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value; the master station control unit 101 obtains the operation control mode based on the relationship between the final predicted safety margin and the preset safety margin threshold, and determines the safety control parameters based on the operation control mode; the master station control unit 101 generates control commands based on the preset safety budget allocation rules, the final safety budget value, the safety control parameters, and the final predicted safety margin, and sends the control commands to the transformer substation side terminal 102 to instruct the transformer substation side terminal 102 to perform output control on the distributed photovoltaic units in the transformer substation based on the control commands. The distributed photovoltaic terminal 103 acquires control commands sent by the transformer substation side terminal 102. The control commands include safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit for each distributed photovoltaic unit. The distributed photovoltaic terminal 103 obtains the reference output command for each distributed photovoltaic unit based on the estimated available output value of each distributed photovoltaic unit at the current moment and the reference output limit for each distributed photovoltaic unit. The distributed photovoltaic terminal 103 generates the actual output of each distributed photovoltaic unit based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control commands, and the final predicted safety margin.

[0053] In one exemplary embodiment, such as Figure 2 As shown, a distributed photovoltaic power output control method is provided, which is applied to... Figure 1The following explanation uses the main station control unit 101 as an example, including steps 201 to 206. Wherein:

[0054] Step 201: Collect the current time window operation status data of the transformer substation and distributed photovoltaic access points.

[0055] The operating status data of the current time window may include phase voltage U, phase current I, and reverse power. It may also include transformer area power P / Q, power factor, photovoltaic output, historical operating sequence, etc.; and may include inverter rated capacity, estimated available output, communication status, etc. In some embodiments, the transformer area can use one distribution transformer as its core. The distributed photovoltaic access point is the physical point where the AC side of the distributed photovoltaic unit is electrically connected to the low-voltage distribution line of the transformer area; simply put, it is the interface through which the electricity generated by the distributed photovoltaic unit is sent to the transformer area. The current time window refers to a continuous time interval with a fixed standardized duration, ending at the current time of data acquisition. Optionally, the current time is t, and the time window is... ,So This is the current time window.

[0056] For example, the main station control unit collects the voltage, current, and reverse power of the distribution area and distributed photovoltaic access points within the current time window. Voltage may include the low-voltage bus phase voltage. The current can include the winding current of the transformer substation. The reverse power can be the reverse power of the transformer area.

[0057] Step 202: Based on the operating status data and preset thresholds, calculate the safety budget value of the transformer area in the next time window, wherein the safety budget value is used to limit the operating status data of the transformer area in the next time window.

[0058] Among them, the preset thresholds can be the maximum reverse power threshold, the maximum current threshold, and the maximum voltage threshold allowed for the transformer area.

[0059] The safety budget value can be generated based on the distance between the operating status and the corresponding safety boundary. It is used to limit the fluctuation range of the operating status data of the transformer area within the next time window, and avoid the instantaneous risks of voltage over-limit and reverse overload from the source.

[0060] For example, the master station control unit calculates the safety budget value for the transformer area within the next time window based on the reverse power in the operating status data and the maximum allowed reverse power threshold for the transformer area. In one example, the safety budget value for the transformer area within the next time window is calculated using the following formula:

[0061]

[0062] in, This is the safety budget value for the transformer area within the next time window. This represents the maximum allowable reverse power threshold for the transformer area. The power transmitted back from the operating status data within the current time window. Power safety margin is used to characterize the safety redundancy space reserved to cope with measurement errors, communication delays, output fluctuations and load uncertainties in the back-feeding power in the operating status data.

[0063] In one embodiment, when the preset threshold is the maximum current threshold, the main station control unit determines the current safety margin based on the difference between the current in the operating status data and the maximum current threshold, and maps the current safety margin to an equivalent power safety margin through a preset power-current conversion relationship. Based on the power safety margin, the safe budget value of the transformer area in the next time window is obtained.

[0064] In one embodiment, when the preset threshold is the maximum voltage threshold, the master station control unit establishes a local influence relationship model based on historical metering sequences and operating status data without needing to obtain the complete distribution network topology or line parameters. This model characterizes the impact trend of photovoltaic power output changes on grid connection voltage changes. The master station control unit maps the voltage margin between the voltage in the operating status data and the maximum voltage threshold, combined with the local influence relationship model, to the allowable maximum power output increment. Based on this maximum power output increment, it generates the corresponding area safety budget.

[0065] Step 203: Based on the maximum rate of change between adjacent windows, perform consistency constraint processing on the safety budget value of the transformer area in the next time window to obtain the final safety budget value of the next time window.

[0066] The maximum rate of change between adjacent windows is preset to avoid frequent budget fluctuations caused by measurement noise, short-term fluctuations, or communication delays.

[0067] For example, the master station control unit performs consistency constraint processing on the safety budget value of the transformer area in the next time window based on the maximum rate of change between preset adjacent windows, and obtains the final safety budget value of the next time window, which satisfies the following formula:

[0068]

[0069] In another embodiment, the following formula is satisfied:

[0070]

[0071] Where k represents the k-th time window, k-1 represents the (k-1)-th time window, and k and k-1 represent the discrete control time steps, respectively. This represents the final safety budget value within the k-th time window; This represents the final safety budget value within the (k-1)th time window. The maximum rate of change of the final safety threshold between preset adjacent windows. The current measurement data is the safety budget value of the transformer area in the next time window, which is directly calculated based on the current measurement data and the safety threshold. The current measurement data is equivalent to the safety budget value of the transformer area in the next time window, and the safety threshold is equivalent to the maximum rate of change between adjacent windows. This value has not been processed by smoothing and consistency constraints. This represents a saturation / limiting function used to restrict the input value within a preset upper and lower limit range; in this embodiment, the saturation function is used to limit the safe budget value of the transformer area within the next time window. Limited to the range This allows us to obtain the final security budget value for the next time window. .

[0072] Step 204: Based on the historical operating status data sequence, obtain the initial predicted safety margin for a preset future time range, and based on the initial predicted safety margin, obtain the final predicted safety margin; wherein, the final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value.

[0073] For example, the master station control unit uses a time-scale modeling method to predict the trend of safety margins within a preset future time range based on historical operational status data sequences, obtaining an initial predicted safety margin, and then obtaining a final predicted safety margin based on the initial predicted safety margin. When the final predicted safety margin shows a downward trend, it indicates that the operational risk within the preset future time range is increasing, and the master station control unit performs a forward contraction operation on the final safety budget value. When the final predicted safety margin shows an upward trend, it indicates that the operational risk within the preset future time range is decreasing and the safety space is increasing, and then a release operation is performed on the final safety budget value.

[0074] Step 205: Based on the relationship between the final predicted safety margin and the preset safety margin threshold, obtain the operation control mode, and determine the safety control parameters based on the operation control mode.

[0075] The operation control modes include normal mode, early warning mode, and emergency mode.

[0076] For example, the master station control unit determines different operating control modes based on the relationship between the final predicted safety margin and the preset safety margin threshold, and determines different safety control parameters according to different operating control modes. In one embodiment, as the operating control mode changes from normal mode to early warning mode and from early warning mode to emergency mode, the upper limit of voltage, upper limit of current, and upper limit of reverse power in the corresponding safety control parameters gradually decrease, and the overall distributed photovoltaic power output control system should respond more conservatively and robustly to risks.

[0077] Step 206: Based on the preset safety budget allocation rules, the final safety budget value, the safety control parameters, and the final predicted safety margin, generate control commands and send the control commands to the distribution area terminal to instruct the distribution area terminal to control the output of the distributed photovoltaic units in the distribution area based on the control commands.

[0078] The preset security budget allocation rules may include allocation based on the proportion of photovoltaic installed capacity, allocation based on the historical output contribution of each distributed photovoltaic unit, and allocation based on the preset weight of each distributed photovoltaic unit.

[0079] A distributed photovoltaic (PV) unit is the smallest power generation and output unit in a distributed PV system. It is the core entity that actually generates electricity. Simply put, it is an independent power generation and output unit consisting of a PV inverter as its core, along with connected PV module arrays, combiner boxes, etc. A distributed PV terminal is a dedicated intelligent control and communication device for a distributed PV unit. The distributed PV unit is the control object and command execution carrier of the distributed PV terminal.

[0080] For example, the master station control unit generates control commands based on the preset safety budget allocation rules, the final safety budget value, safety control parameters, and the final predicted safety margin, and sends the control commands to the distribution area terminal in the distribution area. The control commands instruct the distribution area terminal to generate the output reference upper limit of each distributed photovoltaic unit in the distribution area based on the control commands, and send the output reference upper limit of each distributed photovoltaic unit to the distributed photovoltaic terminal, so that the distributed photovoltaic terminal can confirm the actual output of each distributed photovoltaic unit based on the output reference upper limit of each distributed photovoltaic unit and the control commands.

[0081] In some embodiments, the master station control unit sets a minimum available output ratio for each distributed photovoltaic unit or sets an upper limit for the amount of power curtailed, and integrates the historical power curtailment within multiple time windows; when some distributed photovoltaic units are subject to power curtailment for a long period of time, their allocation weight is appropriately increased in subsequent time windows to form rolling compensation.

[0082] In the aforementioned distributed photovoltaic (PV) output control method, the following steps are taken: First, the operating status data of the transformer substation and distributed PV access points within the current time window is collected. Second, based on the operating status data and a preset threshold, the safety budget value for the transformer substation within the next time window is calculated. This safety budget value is used to limit the operating status data of the transformer substation within the next time window. Third, according to the maximum rate of change between preset adjacent windows, consistency constraints are applied to the safety budget value of the transformer substation within the next time window to obtain the final safety budget value for the next time window. Fourth, based on the historical operating status data sequence, an initial predicted safety margin for a preset future time range is obtained. Finally, based on the initial predicted safety margin, a final predicted safety margin is obtained. This final predicted safety margin is used to perform forward contraction or release operations on the final safety budget value. Finally, based on the final predicted safety margin relative to the preset safety margin... The relationship between the full margin threshold is used to obtain the operation control mode, and based on the operation control mode, safety control parameters are determined. Control commands are generated based on the preset safety budget allocation rules, the final safety budget value, safety control parameters, and the final predicted safety margin, and sent to the distribution area terminal to instruct the terminal to control the output of distributed photovoltaic units in the distribution area. Based on the current time window's operation status data and preset thresholds, the safety budget value for the next time window is calculated continuously, defining a clear safety boundary for the distribution area's operation and limiting the fluctuation range of operation status data from the source. Furthermore, consistency constraints based on the maximum rate of change of adjacent windows are used to avoid sudden changes in the safety budget, ensuring the rationality and stability of the budget value, preventing control misjudgments caused by budget fluctuations, and reducing instantaneous risks. By extrapolating the safety margin for future time ranges based on historical operation status data sequences, forward contraction or release operations are performed on the final predicted safety margin to achieve early risk prediction and proactive control. This technical solution constructs a full-process, refined, and adaptive distributed photovoltaic safety control system for power distribution areas through rolling calculation and allocation of safety budgets at the power distribution area level, forward-looking regulation based on margin trend prediction, and online correction at the terminal side.

[0083] In an exemplary embodiment, an initial predicted safety margin for a preset future time range is obtained based on a historical operating status data sequence, and a final predicted safety margin is obtained based on the initial predicted safety margin, including:

[0084] The historical operating status data sequence is input into a timescale model that corresponds to a preset future time range to obtain the initial prediction safety margin and the uncertainty measure of the initial prediction safety margin for the preset future time range.

[0085] The final predicted safety margin is obtained based on the initial predicted safety margin and uncertainty measure within a preset future time range.

[0086] The time-scale models include short-time-scale models, medium-time-scale models, and long-time-scale models. Short-time-scale models are used to characterize the random fluctuation characteristics of operational status data from the second to the minute level, medium-time-scale models are used to characterize the operational trends of operational status data from the minute to the hour level, and long-time-scale models are used to characterize the periodic changes in intraday operational status data.

[0087] For example, the main station control unit determines the corresponding time scale model based on the preset future time range, and then inputs the historical operating status data sequence into the time scale model that corresponds to the preset future time range to obtain the initial prediction safety margin and the uncertainty measure of the initial prediction safety margin for the preset future time range. The initial prediction safety margin and the uncertainty measure of the preset future time range are then input into the formula to obtain the final prediction safety margin.

[0088] In some embodiments, the master station control unit predicts the future trends of the transformer area's operating status data (including reverse power, transformer current, and low-voltage bus voltage) within minute-level (e.g., 1–5 min) and hour-level (e.g., 15–60 min) time windows, respectively, to obtain the corresponding initial predicted safety margin sequence. Based on the initial predicted safety margin sequence, the master station control unit determines the predicted risk level and applies a predicted margin reduction factor to the transformer area's safety budget accordingly, forming the final predicted safety margin. The transformer area terminal generates a reference output limit for each distributed photovoltaic unit based on the final predicted safety margin, combined with the installed capacity of each distributed photovoltaic unit, the historical contribution of each distributed photovoltaic unit, and the preset weight of each distributed photovoltaic unit. In this way, power generation can be moderately limited in advance before future risks rise, reducing the abandonment and fluctuations caused by subsequent forced power generation limitations.

[0089] In one embodiment, the final preset safety margin can be obtained in the following manner. :

[0090]

[0091] in, The average of the predicted safety margins is equivalent to the initial predicted safety margin. To measure the uncertainty of the corresponding prediction results, is the confidence coefficient, used to adjust the conservatism of the prediction results; t is the current control time or the start time of the current time window; H is the preset future time range, used to represent the time span looking forward; To predict continuous or discrete time variables within a given interval, satisfying .

[0092] Based on historical operational data sequences, it eliminates the need for additional acquisition of complete distribution network topology or line parameters, making it suitable for practical engineering scenarios involving localized control at the distribution substation level. This reduces data acquisition and modeling costs and facilitates large-scale deployment. Furthermore, by dynamically mining operational patterns from historical data and quantifying prediction uncertainties, it can adapt to complex scenarios involving fluctuations in photovoltaic output and dynamic load changes, continuously optimizing prediction accuracy as operational data accumulates.

[0093] In an exemplary embodiment, the preset safety margin threshold includes a first threshold and a second threshold, wherein the first threshold is less than the second threshold; the safety control parameters include a voltage upper limit, a current upper limit, and an output change rate upper limit. Based on the relationship between the final predicted safety margin and the preset safety margin threshold, an operating control mode is obtained, and based on the operating control mode, safety control parameters are determined, including:

[0094] Obtain the current safety margin for the current control cycle;

[0095] When the current safety margin is greater than the first threshold and the final predicted safety margin is greater than the first threshold, the operation control mode is confirmed to be normal mode, and the safety control parameter is confirmed to be the first safety control parameter.

[0096] When the difference between either the current safety margin or the final predicted safety margin and the first threshold is less than a preset difference threshold, and both the safety margin and the final predicted safety margin show a downward trend, the operation control mode is determined to be the early warning mode, and the safety control parameter is determined to be the second safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the first safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter;

[0097] If either the current safety margin or the final predicted safety margin is less than the second threshold, the operation control mode is confirmed as the emergency mode, and the safety control parameter is confirmed as the third safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the third safety control parameter.

[0098] Different operating control modes correspond to different safety control parameters. As the operating control mode changes from normal mode to early warning mode and emergency mode, the corresponding upper limit of voltage, upper limit of current, and upper limit of output change rate gradually decrease, the corresponding confidence coefficient gradually increases, and the maximum change rate between preset adjacent windows gradually decreases.

[0099] For example, the main station control unit obtains the current safety margin of the current control cycle. When the current safety margin is greater than the first threshold and the final predicted safety margin is greater than the first threshold, the operation control mode is confirmed as normal mode, and the safety control parameter is confirmed as the first safety control parameter. When the difference between either the current safety margin or the final predicted safety margin and the first threshold is less than a preset difference threshold, which is equivalent to either the current safety margin or the final predicted safety margin being close to the first threshold, and the safety margin and the final predicted safety margin showing a downward trend, the operation control mode is determined as early warning mode, and the safety control parameter is determined as the second safety control parameter. When either the current safety margin or the final predicted safety margin is less than the second threshold, the operation control mode is confirmed as emergency mode, and the safety control parameter is confirmed as the third safety control parameter. The upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the third safety control parameter.

[0100] The automated nature of the three-level operation control mode and the dynamic switching of three-level safety control parameters can reduce the cost of manual intervention, improve the speed of management and control response, adapt to complex dynamic scenarios of photovoltaic output fluctuations and load changes, and quickly adjust the management and control strategy with the real-time changes of safety margin, ensuring that the operation of the distribution area is always within a safe and reasonable range, and supporting the large-scale and efficient consumption of distributed photovoltaic power in the long term.

[0101] In one exemplary embodiment, such as Figure 3 As shown, a distributed photovoltaic power output control method is provided, which is applied to... Figure 1 The following explanation uses a distributed photovoltaic terminal 103 as an example, including steps 301 to 303. Wherein:

[0102] Step 301: Obtain the control instructions sent by the transformer substation side terminal. The control instructions include the safety budget allocation rules, the final safety budget value, the safety control parameters, the final predicted safety margin, and the reference output limit of each distributed photovoltaic unit.

[0103] The safety budget allocation rules may include allocation based on installed capacity ratio, allocation based on the historical output contribution of each distributed photovoltaic unit, allocation based on the preset weight of each distributed photovoltaic unit, and fairness constraints on each distributed photovoltaic unit. Fairness constraints may include minimum guaranteed output, upper / lower limits of control ratio, and penalties for the number of control cycles.

[0104] The distribution terminal in the transformer area allocates the final safety budget value locally based on the set of connected distributed photovoltaic (PV) units and the safety budget allocation rules, thus obtaining the reference output limit for each distributed PV unit. Here, the set of distributed PV units represents all distributed PV units.

[0105] In one embodiment, the sum of the reference output limits of each distributed photovoltaic unit satisfy:

[0106]

[0107] in, This represents the upper limit of the reference output allowed for the i-th distributed photovoltaic unit within the current time window. This represents the final security budget value.

[0108] In one embodiment, the distribution area terminal can combine the maximum reference output limit of each distributed photovoltaic unit with the final safety budget value to make a secondary correction to the maximum reference output limit of each distributed photovoltaic unit, so as to avoid over-allocation of units that will inevitably be subject to power rationing in the future, thereby improving the overall grid integration efficiency and fairness.

[0109] For example, the distribution terminal in the distribution area allocates the final safety budget value locally based on the set of connected distributed photovoltaic units and the safety budget allocation rules, obtains the reference output limit of each distributed photovoltaic unit, and then sends control commands to the distributed photovoltaic terminal. The control commands include the safety budget allocation rules, the final safety budget value, safety control parameters, the final predicted safety margin, and the reference output limit of each distributed photovoltaic unit.

[0110] Step 302: Based on the estimated available output of each distributed photovoltaic unit at the current moment and the upper limit of the reference output of each distributed photovoltaic unit, obtain the reference output command of each distributed photovoltaic unit.

[0111] The available output estimate of each distributed photovoltaic unit at the current moment can be obtained based on MPPT (Maximum Power Point Tracking) output, irradiance estimation, or short-term prediction, and the output change rate of each distributed photovoltaic unit at the current moment is less than the upper limit of the output change rate in the safety control parameters.

[0112] For example, the distributed photovoltaic terminal obtains the reference output command for each distributed photovoltaic unit based on the estimated available output of each distributed photovoltaic unit at the current moment and the reference output limit of each distributed photovoltaic unit:

[0113]

[0114] in, Let be the estimated available power output of the i-th distributed photovoltaic unit at the current moment. Let be the reference upper limit of the output of the i-th distributed photovoltaic unit. This is the reference output command for the i-th distributed photovoltaic unit.

[0115] In some embodiments, when communication between the master control unit and the distribution area terminal or distributed photovoltaic terminal is abnormal, the distributed photovoltaic terminal operates independently according to the most recently received safety control parameters and continues to perform runtime safety filtering. If the control command validity period expires and no updated safety control parameters are received, the available output estimate is reduced according to a preset backoff strategy or a conservative mode is entered to ensure that voltage / current overruns do not occur. The conservative mode can reduce the upper limit of voltage, the upper limit of current, or increase the confidence coefficient.

[0116] Step 303: Based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin, generate the actual output of each distributed photovoltaic unit.

[0117] For example, the distributed photovoltaic (PV) terminal obtains a safe operating set based on the safety control parameters in the control instructions of each distributed PV unit and the operating status data of the current control cycle. The current time window includes the current control cycle. The distributed PV terminal obtains the current safety margin for the current control cycle based on the safety control parameters in the control instructions and the operating status data of the current control cycle. The distributed PV terminal determines the filtering strength coefficient based on the current safety margin and the final predicted safety margin. Based on the safe operating set, the distributed PV terminal obtains the safe feasible output of each distributed PV terminal, and then generates the actual executed output of each distributed PV unit based on the filtering strength coefficient, the safe feasible output of each distributed PV unit, and the reference output instruction.

[0118] In some embodiments, after each control cycle, the distributed photovoltaic (PV) terminal feeds back its actual output, limiting status information, local influence model parameters, and communication status information to the substation-side terminal and / or the master station control unit. The limiting status information includes at least: whether a power limiting occurred, the extent of the limiting, and the reason for the limiting. The local influence model parameters describe the local response relationship between changes in PV output and changes in grid connection voltage or current. Based on the feedback and through substation measurements, the master station control unit performs consistency verification: comparing the final safety budget value with the actual execution result to obtain the budget deviation, and accordingly performing convergent correction on the weighted or predictive model parameters for the next time window, gradually reducing the safety budget execution deviation and forming a closed-loop control.

[0119] In this embodiment, the distributed photovoltaic (PV) output control method combines the estimated available output of each distributed PV unit with its reference output limit. This allows for dynamic adjustment of the output commands of each unit based on the real-time grid conditions, thereby maximizing the power generation potential of distributed PV while meeting safety constraints. Furthermore, the control commands include safety control parameters, enabling the system to flexibly adjust the actual output of each distributed PV unit according to different grid operating conditions, enhancing its adaptability to complex grid environments.

[0120] In an exemplary embodiment, the safety control parameters include a voltage upper limit, a current upper limit, and a power output change rate upper limit. Based on the reference power output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin, the actual executed power output of each distributed photovoltaic unit is generated, including:

[0121] The current margin is obtained based on the upper limit of current in the safety control parameters and the current in the current control cycle;

[0122] The voltage margin is obtained based on the upper voltage limit in the safety control parameters and the voltage of the current control cycle;

[0123] The output change rate margin is obtained based on the upper limit of the output change rate in the safety control parameters and the output change rate in the current control cycle.

[0124] The minimum value among the current margin, voltage margin, and output change rate margin is taken as the current safety margin for the current control cycle.

[0125] The filtering intensity coefficient is obtained by comparing the current safety margin and the final predicted safety margin with respect to the first threshold and the second threshold, respectively.

[0126] Obtain the safe and feasible output of each distributed photovoltaic unit; wherein the safe and feasible output of each distributed photovoltaic unit satisfies the safe operation set constraint conditions; the safe operation set constraint conditions are obtained based on the safety control parameters;

[0127] Based on the filtration intensity coefficient and the reference output command and safe and feasible output of each distributed photovoltaic unit, the actual executed output of each distributed photovoltaic unit is generated.

[0128] The current margin of distributed photovoltaic terminals can be obtained using the following formula:

[0129]

[0130] in, The current for the current control cycle. This refers to the upper limit of current in the safety control parameters. This represents the current margin.

[0131] The voltage margin of a distributed photovoltaic terminal can be obtained using the following formula:

[0132]

[0133] in, The voltage for the current control cycle. This refers to the upper voltage limit in the safety control parameters. This represents the voltage margin.

[0134] The output change margin of distributed photovoltaic terminals can be obtained using the following formula:

[0135]

[0136] in, The rate of change of output during the current control cycle. This represents the absolute value of the rate of change of output during the current control cycle. This refers to the upper limit of the rate of change of output in the safety control parameters. This represents the margin of the rate of change of output.

[0137] The distributed terminal uses the minimum value among the current margin, voltage margin, and output change rate margin as the current safety margin for the current control cycle.

[0138]

[0139] in, This represents the current safety margin for the current control cycle.

[0140] The safe and feasible output of each distributed photovoltaic unit can satisfy one or more of the safe operation set constraints. The safe operation set constraints can be:

[0141]

[0142]

[0143]

[0144] in, For the first Each distributed photovoltaic unit is in the current control cycle Actual execution output For the first The distributed photovoltaic units in the previous control cycle Actual execution output This represents the absolute value of the rate of change of output within the current control cycle.

[0145] The safe and feasible output of each distributed photovoltaic unit can be obtained through monotonic search / iterative verification, or quickly solved using local influence relationships obtained through online learning. These local influence relationships can be updated using recursive least squares, sliding window regression, or incremental learning with a forgetting factor. The local influence relationships can be:

[0146] ,

[0147] in, The local sensitivity coefficient representing the rate of change of output to voltage change can be simply referred to as the voltage sensitivity coefficient. The local sensitivity coefficient representing the rate of change of output to changes in current can be simply referred to as the current sensitivity coefficient. The rate of change of current, This represents the rate of change of voltage.

[0148] In one embodiment, a model adapted to real-time scenarios, employing incremental learning and reinforcement learning, is constructed. Historical output data and corresponding voltage / current fluctuation data are used as the initial training set to explore the correlation between sensitivity coefficients and operating conditions (load, illumination). When the distributed photovoltaic terminal collects operating data for the current time window, there is no need to retrain the entire model; only the sensitivity coefficients are incrementally updated to ensure that the coefficients accurately match the current operating conditions. For example, when a sudden change in illumination causes a sharp increase in photovoltaic output, the model quickly updates the voltage / current sensitivity coefficients to reflect the impact of output fluctuations on grid parameters in real time. Subsequently, by combining the updated sensitivity coefficients, safety control parameters (voltage / current thresholds), and the final predicted safety margin, the safe and feasible output is dynamically calculated.

[0149] In some embodiments, distributed photovoltaic terminals or substation-side terminals can identify the local impact relationship of "output change - voltage / current change" online to assist in quickly determining safe and feasible output. For example, the following definition is provided: , Where t represents the current time and t-1 represents the previous time, Indicates the actual output at the current moment. Indicates the actual output at the previous moment. The output change rate from t-1 to t can be represented by the recursive least squares online estimation of the local sensitivity coefficient of the output change rate to voltage change. ,make Similarly, the local sensitivity coefficient of the rate of change of output force to the change of current can be estimated. Voltage sensitivity coefficients and current sensitivity coefficients are used to convert safety margins into permissible output adjustments, thereby quickly providing a safe and feasible output without exceeding limits within each control cycle.

[0150] Online learning can be combined with forgetting factors and outlier removal strategies to resist measurement noise and occasional disturbances; when communication is abnormal or the model drift is significant, it can fall back to the monotonic search method to ensure safety.

[0151] In some embodiments, the comparison between the current safety margin and the final predicted safety margin confirmed by the distributed photovoltaic terminal relative to the first threshold and the second threshold respectively indicates that the smaller the current safety margin and the final predicted safety margin, the closer the operating state of the distributed photovoltaic terminal is to the safety boundary, the higher the risk level, and therefore the greater the control intensity triggered, resulting in a smaller filtering intensity coefficient but a greater filtering intensity.

[0152] The actual output of each distributed photovoltaic (PV) unit can be generated by the following formula, based on the filtration intensity coefficient, the reference output command, and the safe and feasible output of each distributed PV unit:

[0153]

[0154] in, For the actual output of the i-th distributed photovoltaic unit, This is the reference output command for the i-th distributed photovoltaic unit. Contribute to the safe and feasible operation of the i-th distributed photovoltaic unit. This is the filtration intensity coefficient.

[0155] By calculating margins across three dimensions—current, voltage, and rate of change of output—a comprehensive assessment of the operating status of distributed photovoltaic (PV) units is achieved, avoiding the limitations of single-dimensional assessments and ensuring the safety of output control. Based on the comparison between the current control cycle's safety margin, the final predicted safety margin, the first threshold, and the second threshold, the filtering intensity is adaptively adjusted, ensuring both the flexibility of output control and avoiding safety risks caused by over-adjustment. Constraints established based on safety control parameters ensure that the actual output meets safe operating requirements, preventing grid shocks caused by sudden output changes.

[0156] In an exemplary embodiment, the filtering strength coefficient is obtained based on the comparison relationship between the current safety margin and the final predicted safety margin relative to a first threshold and a second threshold, respectively, including:

[0157] If the current safety margin is less than the first threshold or the final predicted safety margin is less than the first threshold, then the filtering intensity coefficient is determined to be the first preset value.

[0158] If the current safety margin is greater than the second threshold and the final predicted safety margin is greater than the second threshold, then the filtering intensity coefficient is determined to be the second preset value.

[0159] If the current safety margin is greater than the first threshold and less than the second threshold, or the final predicted safety margin is greater than the first threshold and less than the second threshold, then the filtering intensity coefficient is determined to be the third preset value; wherein, as the target value increases, the third preset value increases monotonically; the target value is the minimum value between the current safety margin and the final predicted safety margin; the first preset value is less than the third preset value; the third preset value is less than the second preset value.

[0160] For example, a piecewise function is used to determine the filter strength coefficient:

[0161] when or At that time, ,

[0162] Where 0 is the first preset value, The first threshold, For the current safety margin, This is for the final prediction of safety margin.

[0163] when and At that time, ,

[0164] Where 1 is the second preset value. This is the second threshold.

[0165] when or At that time, along with It increases and monotonically intensifies, among which, This is the target value.

[0166] In some embodiments, in each control cycle, the distributed photovoltaic terminal calculates the current voltage margin and current margin, and also receives short-term forecast margin or forecast risk level issued by the main station control unit or the transformer substation terminal. When the short-term forecast margin indicates that the voltage margin may approach the safety boundary in the future, the distributed photovoltaic terminal lowers the upper limit of the filtering intensity coefficient or moves the threshold or the overall filter forward, so that the system can enter the medium filtering state in advance while it is still safe, thus achieving early tightening. When the short-term forecast margin indicates that the future risk is reduced, the distributed photovoltaic terminal relaxes the filtering intensity, so that the actual output can recover to near the reference output command more quickly.

[0167] By employing dual-threshold grading and OR / AND logic judgment, a solid safety baseline for grid operation is established; monotonically increasing adjustment in the intermediate range eliminates sudden command changes and adapts to grid-connected power quality requirements; and by integrating current safety margins with final predicted safety margins, photovoltaic absorption and dispatch adaptability are maximized while ensuring safety.

[0168] It should be understood that although the steps in the flowcharts of the above embodiments are shown sequentially according to the arrows, these steps are not necessarily executed in the order indicated by the arrows. Unless explicitly stated herein, there is no strict order restriction on the execution of these steps, and they can be executed in other orders. Moreover, at least some steps in the flowcharts of the above embodiments may include multiple steps or multiple stages. These steps or stages are not necessarily completed at the same time, but can be executed at different times. The execution order of these steps or stages is not necessarily sequential, but can be performed alternately or in turn with other steps or at least some of the steps or stages of other steps.

[0169] In one exemplary embodiment, such as Figure 4 As shown, a distributed photovoltaic (PV) power output control system is provided. The system includes a master station control unit 401, a transformer substation side terminal 402, and a distributed PV terminal 403. The master station control unit 401, the transformer substation side terminal 402, and the distributed PV terminal 403 are connected via a communication network.

[0170] The main station control unit 401 is used to collect the operating status data of the transformer substation and distributed photovoltaic access points in the current time window; based on the operating status data and preset thresholds, it calculates the safety budget value of the transformer substation in the next time window, where the safety budget value is used to limit the operating status data of the transformer substation in the next time window; according to the maximum rate of change between preset adjacent windows, it performs consistency constraint processing on the safety budget value of the transformer substation in the next time window to obtain the final safety budget value of the next time window; based on the historical operating status data sequence, it obtains the initial predicted safety margin for a preset future time range, and based on the initial predicted safety margin, it obtains the final predicted safety margin; where the final predicted safety margin is used to perform look-ahead contraction or release operations on the final safety budget value; based on the relationship between the final predicted safety margin and the preset safety margin threshold, it obtains the operation control mode, and based on the operation control mode, it determines the safety control parameters; based on the preset safety budget allocation rules, the final safety budget value, the safety control parameters, and the final predicted safety margin, it generates control commands and sends the control commands to the transformer substation side terminal to instruct the transformer substation side terminal to perform output control on the distributed photovoltaic units in the transformer substation based on the control commands;

[0171] The transformer substation terminal 402 is used to receive control commands sent by the main station control unit and send the control commands to the distributed photovoltaic terminal.

[0172] The distributed photovoltaic terminal 403 is used to acquire control commands sent by the transformer substation side terminal. The control commands include safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit of each distributed photovoltaic unit. Based on the current available output estimate of each distributed photovoltaic unit and the reference output limit of each distributed photovoltaic unit, the reference output command of each distributed photovoltaic unit is obtained. Based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control commands, and the final predicted safety margin, the actual output of each distributed photovoltaic unit is generated.

[0173] Based on the same inventive concept, this application also provides a distributed photovoltaic power output control device for implementing the distributed photovoltaic power output control method described above. The solution provided by this device is similar to the solution described in the above method; therefore, the specific limitations in one or more embodiments of the distributed photovoltaic power output control device provided below can be found in the limitations of the distributed photovoltaic power output control method described above, and will not be repeated here.

[0174] In one exemplary embodiment, such as Figure 5 As shown, a distributed photovoltaic power output control device applied to a master station control unit is provided, comprising: a data acquisition module 501, a calculation module 502, a first acquisition module 503, a second acquisition module 504, a third acquisition module 505, and a first generation module 506, wherein:

[0175] The data acquisition module 501 is used to collect the operating status data of the transformer substation and distributed photovoltaic access points within the current time window;

[0176] The calculation module 502 is used to calculate the safety budget value of the transformer area in the next time window based on the operating status data and the preset threshold. The safety budget value is used to limit the operating status data of the transformer area in the next time window.

[0177] The first obtaining module 503 is used to perform consistency constraint processing on the safety budget value of the transformer area in the next time window according to the maximum change rate between preset adjacent windows, so as to obtain the final safety budget value of the next time window.

[0178] The second module 504 is used to obtain an initial predicted safety margin for a preset future time range based on the historical operating status data sequence, and to obtain a final predicted safety margin based on the initial predicted safety margin; wherein, the final predicted safety margin is used to perform a forward contraction operation or a release operation on the final safety budget value.

[0179] The third module 505 is used to obtain the operation control mode based on the relationship between the final predicted safety margin and the preset safety margin threshold, and to determine the safety control parameters based on the operation control mode.

[0180] The first generation module 506 is used to generate control commands based on the preset safety budget allocation rules, the final safety budget value, the safety control parameters and the final predicted safety margin, and send the control commands to the transformer substation side terminal to instruct the transformer substation side terminal to control the output of the distributed photovoltaic units in the transformer substation based on the control commands.

[0181] In an optional embodiment, the first obtaining module 503 is further configured to input the historical operating status data sequence into a time scale model that corresponds to a preset future time range, to obtain the initial prediction safety margin and the uncertainty measure of the initial prediction safety margin for the preset future time range; and to obtain the final prediction safety margin based on the initial prediction safety margin and the uncertainty measure of the preset future time range.

[0182] In an optional embodiment, the third obtaining module 505 is further configured to obtain the current safety margin of the current control cycle; when the current safety margin is greater than the first threshold and the final predicted safety margin is greater than the first threshold, the operating control mode is confirmed as normal mode, and the safety control parameter is confirmed as the first safety control parameter; when the difference between either the current safety margin or the final predicted safety margin and the first threshold is less than a preset difference threshold, and the safety margin and the final predicted safety margin show a downward trend, the operating control mode is determined as an early warning mode, and the safety control parameter is determined as the second safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the first safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter; when either the current safety margin or the final predicted safety margin is less than the second threshold, the operating control mode is confirmed as emergency mode, and the safety control parameter is confirmed as the third safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the third safety control parameter.

[0183] In one exemplary embodiment, such as Figure 6 As shown, a distributed photovoltaic output control device for distributed photovoltaic terminals is provided, comprising: an acquisition module 601, a fourth obtaining module 602, and a second generating module 603, wherein:

[0184] The acquisition module 601 is used to acquire control commands sent by the transformer substation side terminal. The control commands include safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit of each distributed photovoltaic unit.

[0185] The fourth module 602 is used to obtain the reference output command of each distributed photovoltaic unit based on the estimated available output value of each distributed photovoltaic unit at the current moment and the reference output limit of each distributed photovoltaic unit.

[0186] The second generation module 603 is used to generate the actual output of each distributed photovoltaic unit based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin.

[0187] In an optional embodiment, the second generation module 603 is further configured to: obtain a current margin based on the upper limit of current in the safety control parameters and the current in the current control cycle; obtain a voltage margin based on the upper limit of voltage in the safety control parameters and the voltage in the current control cycle; obtain an output change rate margin based on the upper limit of output change rate in the safety control parameters and the output change rate in the current control cycle; take the minimum value among the current margin, voltage margin, and output change rate margin as the current safety margin for the current control cycle; obtain a filtering intensity coefficient based on the comparison relationship between the current safety margin and the final predicted safety margin relative to the first threshold and the second threshold, respectively; obtain the safe feasible output of each distributed photovoltaic unit; wherein the safe feasible output of each distributed photovoltaic unit satisfies the safe operation set constraint conditions; the safe operation set constraint conditions are obtained based on the safety control parameters; and generate the actual executed output of each distributed photovoltaic unit based on the filtering intensity coefficient and the reference output command and safe feasible output of each distributed photovoltaic unit.

[0188] In an optional embodiment, the second generation module 603 is further configured to: determine a first preset value for the filtering intensity coefficient when the current safety margin is less than a first threshold or the final predicted safety margin is less than the first threshold; determine a second preset value for the filtering intensity coefficient when the current safety margin is greater than a second threshold and the final predicted safety margin is greater than the second threshold; and determine a third preset value for the filtering intensity coefficient when the current safety margin is greater than the first threshold and less than the second threshold, or the final predicted safety margin is greater than the first threshold and less than the second threshold. The third preset value increases monotonically as the target value increases. The target value is the minimum of the current safety margin and the final predicted safety margin. The first preset value is less than the third preset value. The third preset value is less than the second preset value.

[0189] Each module in the aforementioned distributed photovoltaic power output control device can be implemented entirely or partially through software, hardware, or a combination thereof. These modules can be embedded in or independent of the processor in a computer device in hardware form, or stored in the memory of a computer device in software form, so that the processor can call and execute the operations corresponding to each module.

[0190] In one exemplary embodiment, a computer device is provided, which may be a server or a terminal, and its internal structure diagram may be as follows. Figure 7 As shown, this computer device includes a processor, memory, input / output (I / O) interfaces, and a communication interface. The processor, memory, and I / O interfaces are connected via a system bus, and the communication interface is also connected to the system bus via the I / O interfaces. The processor provides computational and control capabilities. The memory includes non-volatile storage media and internal memory. The non-volatile storage media stores the operating system, computer programs, and a database. The internal memory provides the environment for the operation of the operating system and computer programs stored in the non-volatile storage media. The database stores operational status data. The I / O interfaces are used for exchanging information between the processor and external devices. The communication interface is used for communication with external terminals via a network connection. When the computer program is executed by the processor, it implements a distributed photovoltaic power output control method.

[0191] Those skilled in the art will understand that Figure 7 The structure shown is merely a block diagram of a portion of the structure related to the present application and does not constitute a limitation on the computer device to which the present application is applied. Specific computer devices may include more or fewer components than those shown in the figure, or combine certain components, or have different component arrangements.

[0192] In one embodiment, a computer device is also provided, including a memory and a processor, wherein the memory stores a computer program, and the processor executes the computer program to implement the steps in the above method embodiments.

[0193] In one embodiment, a computer-readable storage medium is provided having a computer program stored thereon that, when executed by a processor, implements the steps in the above method embodiments.

[0194] In one embodiment, a computer program product is provided, including a computer program that, when executed by a processor, implements the steps in the above method embodiments.

[0195] It should be noted that the user information (including but not limited to user device information, user personal information, etc.) and data (including but not limited to data used for analysis, data stored, data displayed, etc.) involved in this application are all information and data authorized by the user or fully authorized by all parties, and the collection, use and processing of the relevant data must comply with relevant regulations.

[0196] Those skilled in the art will understand that all or part of the processes in the methods of the above embodiments can be implemented by a computer program instructing related hardware. The computer program can be stored in a non-volatile computer-readable storage medium. When executed, the computer program can include the processes of the embodiments of the above methods. Any references to memory, databases, or other media used in the embodiments provided in this application can include at least one of non-volatile memory and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can take many forms, such as Static Random Access Memory (SRAM) or Dynamic Random Access Memory (DRAM). The databases involved in the embodiments provided in this application may include at least one type of relational database and non-relational database. Non-relational databases may include, but are not limited to, blockchain-based distributed databases. The processors involved in the embodiments provided in this application may be general-purpose processors, central processing units, graphics processing units, digital signal processors, programmable logic devices, quantum computing-based data processing logic devices, artificial intelligence (AI) processors, etc., and are not limited to these.

[0197] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this application.

[0198] The above embodiments are merely illustrative of several implementation methods of this application, and their descriptions are relatively specific and detailed. However, they should not be construed as limiting the scope of this application. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this application should be determined by the appended claims.

Claims

1. A method for controlling distributed photovoltaic power output, characterized in that, Applied to the master station control unit, the method includes: Collect the current time window's operating status data for the transformer substation and distributed photovoltaic access points; Based on the back-transmission power, preset threshold, and power safety margin included in the operating status data, the safety budget value of the transformer area in the next time window is calculated. The preset threshold includes the maximum back-transmission power threshold allowed for the transformer area. The power safety margin is used to characterize the safety redundancy space reserved to cope with the measurement error, communication delay, output fluctuation and load uncertainty of the back-transmission power in the operating status data. The safety budget value is used to limit the operating status data of the transformer area in the next time window. Based on the maximum rate of change between adjacent windows, the safety budget value of the transformer area in the next time window is subjected to consistency constraint processing to obtain the final safety budget value of the next time window. The historical operating status data sequence is input into a timescale model that corresponds to a preset future time range to obtain the initial prediction safety margin of the preset future time range and the uncertainty measure of the initial prediction safety margin. Based on the initial predicted safety margin within the preset future time range and the uncertainty measure, a final predicted safety margin is obtained; wherein, when the final predicted safety margin shows a downward trend, the final predicted safety margin is used to perform a forward contraction operation on the final safety budget value; when the final predicted safety margin shows an upward trend, the final predicted safety margin is used to perform a release operation on the final safety budget value. Based on the relationship between the final predicted safety margin and the preset safety margin threshold, the operation control mode is obtained, and the safety control parameters are determined based on the operation control mode. Based on the preset safety budget allocation rules, the final safety budget value, the safety control parameters, and the final predicted safety margin, a control command is generated and sent to the transformer substation side terminal to instruct the transformer substation side terminal to control the output of the distributed photovoltaic units in the transformer substation based on the control command.

2. The method according to claim 1, characterized in that, The preset safety margin threshold includes a first threshold and a second threshold, wherein the first threshold is less than the second threshold; the safety control parameters include an upper limit for voltage, an upper limit for current, and an upper limit for output change rate; the operation control mode is obtained based on the relationship between the final predicted safety margin and the preset safety margin threshold, and the safety control parameters are determined based on the operation control mode, including: Obtain the current safety margin for the current control cycle; When the current safety margin is greater than the first threshold and the final predicted safety margin is greater than the first threshold, the operation control mode is confirmed to be the normal mode, and the safety control parameter is confirmed to be the first safety control parameter. When the difference between either the current safety margin or the final predicted safety margin and the first threshold is less than a preset difference threshold, and both the safety margin and the final predicted safety margin show a downward trend, the operation control mode is determined to be an early warning mode, and the safety control parameter is determined to be a second safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the first safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter; If either the current safety margin or the final predicted safety margin is less than the second threshold, the operation control mode is confirmed as the emergency mode, and the safety control parameter is confirmed as the third safety control parameter; the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the second safety control parameter are respectively greater than the upper limit of voltage, the upper limit of current, and the upper limit of output change rate in the third safety control parameter.

3. A method for controlling distributed photovoltaic power output, characterized in that, Applied to distributed photovoltaic terminals, the method includes: The system acquires control commands sent by the distribution area terminal, the control commands including safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit for each distributed photovoltaic unit; the control commands are determined by the master station control unit based on the distributed photovoltaic output control method as described in claim 1 or 2. Based on the estimated available output of each distributed photovoltaic unit at the current moment and the upper limit of the reference output of each distributed photovoltaic unit, the reference output command of each distributed photovoltaic unit is obtained. The actual output of each distributed photovoltaic unit is generated based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin.

4. The method according to claim 3, characterized in that, The safety control parameters include a voltage upper limit, a current upper limit, and a power output change rate upper limit. Generating the actual output of each distributed photovoltaic unit based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin includes: The current margin is obtained based on the upper limit of current in the safety control parameters and the current in the current control cycle; The voltage margin is obtained based on the upper voltage limit in the safety control parameters and the voltage of the current control cycle; The output change rate margin is obtained based on the upper limit of the output change rate in the safety control parameters and the output change rate in the current control cycle. The minimum value among the current margin, the voltage margin, and the output change rate margin is taken as the current safety margin for the current control cycle. The filtering intensity coefficient is obtained based on the comparison relationship between the current safety margin and the final predicted safety margin relative to the first threshold and the second threshold, respectively. Obtain the safe and feasible output of each of the distributed photovoltaic units; wherein the safe and feasible output of each of the distributed photovoltaic units satisfies the safe operation set constraint conditions; the safe operation set constraint conditions are obtained based on the safety control parameters; The actual output of each distributed photovoltaic unit is generated based on the filter intensity coefficient, the reference output command, and the safe and feasible output of each distributed photovoltaic unit.

5. The method according to claim 4, characterized in that, The step of obtaining the filtering strength coefficient based on the comparison relationship between the current safety margin and the final predicted safety margin relative to the first threshold and the second threshold, respectively, includes: If the current safety margin is less than the first threshold or the final predicted safety margin is less than the first threshold, then the filtering intensity coefficient is determined to be a first preset value. If the current safety margin is greater than the second threshold and the final predicted safety margin is greater than the second threshold, then the filtering intensity coefficient is determined to be the second preset value. If the current safety margin is greater than the first threshold and less than the second threshold, or the final predicted safety margin is greater than the first threshold and less than the second threshold, then the filtering intensity coefficient is determined to be a third preset value; wherein, as the target value increases, the third preset value increases monotonically; the target value is the minimum of the current safety margin and the final predicted safety margin; the first preset value is less than the third preset value; and the third preset value is less than the second preset value.

6. A distributed photovoltaic power output control system, characterized in that, It includes a main station control unit, a transformer area-side terminal, and distributed photovoltaic terminals; the main station control unit, the transformer area-side terminal, and the distributed photovoltaic terminals are connected through a communication network. The main station control unit is used to implement the steps of the method according to any one of claims 1 to 2; The transformer substation terminal is used to receive control commands sent by the main station control unit and send the control commands to the distributed photovoltaic terminal. The distributed photovoltaic terminal is used to implement the steps of the method according to any one of claims 3 to 5.

7. A distributed photovoltaic power output control device, characterized in that, The device, applied to the main station control unit, includes: The data acquisition module is used to collect the operating status data of the transformer substation and distributed photovoltaic access points within the current time window; The calculation module is used to calculate the safety budget value of the transformer area in the next time window based on the back-transmission power, preset threshold and power safety margin included in the operating status data. The preset threshold includes the maximum allowed back-transmission power threshold of the transformer area. The power safety margin is used to characterize the safety redundancy space reserved to cope with the measurement error, communication delay, output fluctuation and load uncertainty of the back-transmission power in the operating status data. The safety budget value is used to limit the operating status data of the transformer area in the next time window. The first obtaining module is used to perform consistency constraint processing on the safety budget value of the transformer area in the next time window according to the maximum change rate between preset adjacent windows, so as to obtain the final safety budget value of the next time window. The second obtaining module is used to input historical operating status data sequences into a timescale model that corresponds to a preset future time range, to obtain an initial predicted safety margin and an uncertainty measure of the initial predicted safety margin for the preset future time range; and to obtain a final predicted safety margin based on the initial predicted safety margin and the uncertainty measure for the preset future time range; wherein, when the final predicted safety margin shows a downward trend, the final predicted safety margin is used to perform a forward contraction operation on the final safety budget value; and when the final predicted safety margin shows an upward trend, the final predicted safety margin is used to perform a release operation on the final safety budget value. The third obtaining module is used to obtain the operation control mode based on the relationship between the final predicted safety margin and the preset safety margin threshold, and to determine the safety control parameters based on the operation control mode. The first generation module is used to generate control instructions based on the preset security budget allocation rules, the final security budget value, the security control parameters, and the final predicted security margin, and send the control instructions to the transformer substation side terminal to instruct the transformer substation side terminal to perform power output control on the distributed photovoltaic units in the transformer substation based on the control instructions.

8. A distributed photovoltaic power output control device, characterized in that, The device, applied to distributed photovoltaic terminals, includes: The acquisition module is used to acquire control commands sent by the transformer substation side terminal. The control commands include safety budget allocation rules, final safety budget value, safety control parameters, final predicted safety margin, and reference output limit of each distributed photovoltaic unit. The control commands are determined by the master station control unit based on the distributed photovoltaic output control method as described in claim 1 or 2. The fourth module is used to obtain the reference output command of each distributed photovoltaic unit based on the estimated available output value of each distributed photovoltaic unit at the current moment and the reference output upper limit of each distributed photovoltaic unit. The second generation module is used to generate the actual output of each distributed photovoltaic unit based on the reference output command of each distributed photovoltaic unit, the safety control parameters in the control command, and the final predicted safety margin.

9. A computer device comprising a memory and a processor, wherein the memory stores a computer program, characterized in that, When the processor executes the computer program, it implements the steps of the method according to any one of claims 1 to 2 or 3 to 5.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method according to any one of claims 1 to 2 or 3 to 5.

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