Intelligent power supply and distribution management system and method for large-scale power grid

Abstract

The invention provides an intelligent power supply and distribution management system and method for a large-scale power grid, and the method comprises the steps: dividing historical power supply information into an internal power supply load and an external power supply load through an access mode of each power supply in a power microgrid; determining load isolation characteristics of the power microgrid in a grid-connected mode through an external power supply load and an internal power supply load; predicting a recent load and a long-term load of the power micro-grid in the off-grid mode based on the power distribution load information, determining a load margin of the power micro-grid in the off-grid mode according to the long-term load and load isolation characteristics, and determining a load amplitude of the power micro-grid in the off-grid mode through the load margin and the recent load; and when the load amplitude is lower than the load upper limit of the power microgrid, automatically switching the dispatching mode of the power microgrid in the large-scale power grid from a grid-connected mode to an off-grid mode. Based on the scheme, automatic switching of the scheduling modes of the power microgrid in a large-scale power grid can be realized, so that the energy utilization rate in the power microgrid can be improved.

Description

Technical Field

[0001] The present application relates to the technical field of power supply and distribution scheduling of large-scale power grids. More specifically, the present application relates to an intelligent power supply and distribution management system and method for large-scale power grids. Background Art

[0002] With the rapid growth of electricity demand and the widespread access to renewable energy, the power supply and distribution systems of large-scale power grids are becoming increasingly complex. The traditional power grid dispatching method mainly relies on centralized control systems to coordinate the dispatching of power generation, transmission and distribution ends. However, with the widespread application of distributed energy such as wind power and solar energy, the traditional centralized dispatching method faces multiple challenges. There are a large number of power microgrids in large-scale power grids. Power microgrids can operate independently or in parallel with the main power grid to form a highly flexible power supply mode.

[0003] In the existing technology, the switching of dispatching modes of power microgrids in large-scale power grids (from grid-connected to off-grid) mostly relies on manual intervention or simple control logic based on preset conditions. Due to the singleness of manual operation or preset conditions, the power microgrid cannot respond quickly when the external power grid fails or the load fluctuates, which may cause power outages or load instability. The traditional mode cannot be flexibly switched according to the real-time operating status of the power microgrid, the internal power supply capacity and the external load changes, resulting in low utilization of energy resources, and may lead to over-reliance on the main power grid or neglect of the renewable energy potential within the power microgrid. Therefore, how to realize the automatic switching of the dispatching mode of the power microgrid in the large-scale power grid, so as to improve the energy utilization rate in the power microgrid, is a difficult problem faced by the industry. Summary of the invention

[0004] The present application provides an intelligent power supply and distribution management system and method for a large-scale power grid, which can realize the automatic switching of the dispatching mode of a power microgrid in the large-scale power grid, thereby improving the energy utilization rate in the power microgrid.

[0005] In a first aspect, the present application provides a method for switching a dispatching mode of a power microgrid in a large-scale power grid, comprising: Monitor the power microgrid in the grid-connected mode of the large-scale power grid, and collect the historical power supply information and distribution load information of the power microgrid within a specified time period; Dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determining the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; Based on the distribution load information and the grid load prediction model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted; the load margin of the power microgrid in the off-grid mode is determined according to the long-term load and the load isolation characteristic; and the load amplitude of the power microgrid in the off-grid mode is determined according to the load margin and the short-term load; When the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode.

[0006] In some embodiments, dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid specifically includes: For each power supply source in the power microgrid, the power source of the power supply source is determined according to the access mode of the power supply source; If the power source is inside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the internal power supply; If the power source is outside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the external power supply; Then all internal power supplies and all external power supplies are obtained; The internal power supply load is determined based on all internal power supplies, and the external power supply load is determined based on all external power supplies.

[0007] In some embodiments, determining the load isolation characteristics of the power microgrid in the grid-connected mode by using the external power supply load and the internal power supply load specifically includes: determining a temporal correlation between the externally powered load and the internally powered load; Determining the external dependence of the power microgrid in the grid-connected mode according to the external power supply load; The load isolation characteristic of the power microgrid in the grid-connected mode is determined according to the time correlation and the external dependency.

[0008] In some embodiments, predicting the short-term load and long-term load of the power microgrid in the off-grid mode based on the distribution load information combined with the grid load prediction model specifically includes: Determine the dispatching load of the power microgrid in the grid-connected mode according to the distribution load information; Determining a load stability value of the power microgrid by using the dispatching load and the load isolation characteristic; When the load stability value is lower than the load upper limit of the power microgrid, constructing a power grid load prediction model according to the power distribution load information; Based on the grid load prediction model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted.

[0009] In some embodiments, determining the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristic specifically includes: Obtain the internal power supply of the power microgrid in off-grid mode; Determining a power supply capacity of the power microgrid according to the internal power supply amount and the load isolation characteristic; The load margin of the power microgrid in the off-grid mode is determined according to the power supply capacity and the long-term load.

[0010] In some embodiments, determining the load amplitude of the power microgrid in the off-grid mode by using the load margin and the recent load specifically includes: Obtaining load stability of power microgrid in off-grid mode; Determining a limit fluctuation value of a load of the power microgrid in an off-grid mode according to the load stability and the load margin; The load amplitude of the power microgrid in the off-grid mode is determined according to the limit fluctuation value and the recent load.

[0011] In some embodiments, the large-scale power grid is a 750 kV AC power transmission network based on wind power generation.

[0012] In a second aspect, the present application provides an intelligent power supply and distribution management system for a large-scale power grid, including a dispatching mode switching unit, wherein the dispatching mode switching unit includes: A collection module is used to collect historical power supply information and distribution load information of the power microgrid within a specified time period; A processing module, used to divide the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determine the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; The processing module is also used to predict the short-term load and long-term load of the power microgrid in the off-grid mode based on the distribution load information combined with the power grid load prediction model, determine the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristic, and determine the load amplitude of the power microgrid in the off-grid mode according to the load margin and the short-term load; The execution module is used to automatically switch the dispatching mode of the power microgrid in the large-scale power grid from the grid-connected mode to the off-grid mode when the load amplitude is lower than the load upper limit of the power microgrid.

[0013] In a third aspect, the present application provides a computer device, comprising a memory and a processor, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program from the memory, so that the computer device executes the above-mentioned method for switching the dispatching mode of a power microgrid in a large-scale power grid.

[0014] In a fourth aspect, the present application provides a computer-readable storage medium, in which instructions or codes are stored. When the instructions or codes are executed on a computer, the computer implements the above-mentioned method for switching the dispatching mode of a power microgrid in a large-scale power grid when executing the computer.

[0015] The technical solution provided by the embodiments disclosed in this application has the following beneficial effects: In an intelligent power supply and distribution management system and method for a large-scale power grid provided in the present application, a power microgrid in a grid-connected mode of the large-scale power grid is monitored, and historical power supply information and distribution load information of the power microgrid within a specified time period are collected; Dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determining the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; Based on the distribution load information and the grid load prediction model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted; the load margin of the power microgrid in the off-grid mode is determined according to the long-term load and the load isolation characteristic; and the load amplitude of the power microgrid in the off-grid mode is determined according to the load margin and the short-term load; When the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode.

[0016] It can be seen that in this application, when the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode; first, the determination of the load isolation characteristic is based on the analysis of the internal power supply load and the external power supply load. Through the evaluation of time correlation and external dependence, the independence of the power microgrid in the grid-connected mode can be quantified. The load isolation characteristic determines whether the power microgrid can maintain stable operation in the face of external power grid fluctuations and under what conditions it can achieve independent operation (off-grid mode). The stronger the load isolation characteristic, the less dependent the power microgrid is on external power supply, which helps to reduce the impact of external fluctuations on the internal system and improve the independent operation capability and energy utilization efficiency of the power microgrid; then, the determination of the load amplitude depends on the calculation of the load margin and the recent load. The load amplitude reflects the load fluctuation range that the power microgrid can withstand in the off-grid mode. Through reasonable amplitude management, the power microgrid can maintain stable operation when the load fluctuates, which not only avoids excessive energy consumption, but also ensures the optimal configuration of energy. When the load amplitude is lower than the load upper limit of the power microgrid, the power microgrid can be automatically switched to off-grid mode, thereby making full use of the internal resources of the power microgrid and reducing the power microgrid's dependence on the external power grid; in summary, based on the above scheme, the automatic switching of the dispatching mode of the power microgrid in the large-scale power grid can be realized, thereby improving the energy utilization rate in the power microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0018] Figure 1 is an exemplary flow chart of a method for switching a dispatching mode of a power microgrid in a large-scale power grid according to some embodiments of the present application; Figure 2 is a logic diagram of scheduling mode switching according to some embodiments of the present application; Figure 3 It is a schematic diagram of the process of power grid load prediction shown in some embodiments of the present application; Figure 4 is a schematic diagram of an exemplary hardware and / or software structure of a scheduling mode switching unit according to some embodiments of the present application; Figure 5 It is a structural schematic diagram of a computer device for implementing a method for switching a dispatching mode of a power microgrid in a large-scale power grid according to some embodiments of the present application. DETAILED DESCRIPTION

[0019] The following will be combined with the drawings in the embodiments of the present application to clearly and completely describe the technical solutions in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, not all of the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of this application.

[0020] In order to better understand the technical solution of the present application, the technical solution of the present application will be described in detail below in conjunction with the accompanying drawings and specific implementation methods.

[0021] refer to Figure 1 , which is an exemplary flow chart of a method for switching a dispatching mode of a power microgrid in a large-scale power grid according to some embodiments of the present application, and the method for switching a dispatching mode of a power microgrid in a large-scale power grid mainly includes the following steps: In step 101, a power microgrid in a grid-connected mode of a large-scale power grid is monitored, and historical power supply information and distribution load information of the power microgrid within a specified time period are collected.

[0022] It should be noted that, in the present application, historical power supply information refers to a data set of the power supply of the power microgrid within a specified time period; distribution load information refers to a data set of the power distribution of the power microgrid within a specified time period; the power microgrid is a small power system, which can supply power to loads in the region through local power generation equipment, and can operate independently or be connected to the main power grid in a large-scale power grid to flexibly respond to external power fluctuations and demands; the grid-connected mode refers to an operating mode in which the power microgrid is connected to the main power grid and obtains power resources from the main power grid to jointly supply power to the load. In the grid-connected mode, the power microgrid is connected to the large-scale power grid to jointly participate in power supply and load sharing to ensure power supply stability; the off-grid mode refers to a mode in which the power microgrid is disconnected from the main power grid, operates independently and is powered by internal power generation sources and energy storage systems. In the off-grid mode, the power microgrid is disconnected from the large-scale power grid, and the power microgrid independently supplies internal power and loads.

[0023] In specific implementation, the power microgrid in the grid-connected mode of the large-scale power grid is monitored, and the power supply of each power supply source and the distribution of each load device in the power microgrid within a specified time period (the default is the last month) are collected at fixed time intervals (the default is 5 minutes). The collection of all power supplies can be used as historical power supply information, and the collection of all distribution amounts can be used as distribution load information.

[0024] In some embodiments, reference Figure 2, this figure is a logic diagram of the dispatching mode switching shown in some embodiments of the present application. The logic diagram describes the switching logic of the power system between different operating modes. First, the power microgrid operates in the "connected to the distribution network and grid-connected operation" mode. At this time, the power microgrid is connected to the main power grid. If a voltage abnormality is detected, the power microgrid will enter the "energy storage voltage regulation" state and try to stabilize the voltage through energy storage equipment. If the voltage recovers, the system will return to the grid-connected operation state; if a fault causes an artificial power outage, or the power microgrid loses power and the distribution network has no fault, the power microgrid will try to start the grid-connected source and resume grid-connected operation.

[0025] If the power microgrid cannot resume grid-connected operation, or is black-started based on the energy storage main power supply, the power microgrid will switch to the "isolated grid operation based on the energy storage main power supply" mode. In the isolated grid mode, the power microgrid does not rely on the main grid, but uses energy storage equipment as the main power supply. When the main grid returns to normal, the power microgrid will perform logical judgment. If the conditions are met, it will execute the "isolated grid to grid-connected switching", reconnect to the grid and resume grid-connected operation.

[0026] In step 102, the historical power supply information is divided into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and the load isolation characteristics of the power microgrid in the grid-connected mode are determined by the external power supply loads and the internal power supply loads.

[0027] It should be noted that, in the present application, the access mode of the power supply refers to the way in which the power supply is connected to the load, including the device identification and access point data, wherein the access point data includes the access interface, access mode and access source; in specific implementation, the device identification and access point data of each power supply can be obtained in the topological structure diagram of the power microgrid, and the set of device identification and access point data can be used as the access mode of the corresponding power supply, so as to obtain the access mode of each power supply in the power microgrid.

[0028] In some embodiments, dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid can be implemented by the following steps: For each power supply source in the power microgrid, the power source of the power supply source is determined according to the access mode of the power supply source; If the power source is inside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the internal power supply; If the power source is outside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the external power supply; Then all internal power supplies and all external power supplies are obtained; The internal power supply load is determined based on all internal power supplies, and the external power supply load is determined based on all external power supplies.

[0029] It should be noted that in the present application, the external power supply load refers to the power load supplied by the large-scale power grid, that is, the load in the power microgrid is powered by the external power grid, and the internal power supply load refers to the power load supplied by the internal power supply, that is, the load in the power microgrid is powered by the local power generation equipment; in specific implementation, first, for each power supply source in the power microgrid, a network topology analysis algorithm based on graph theory is used to regard the power supply source as a node in the network, and the device identification and access point data of the power supply source are analyzed. The analysis result can be used as the power source of the power supply source, and the power source includes the power microgrid and the power microgrid; secondly, if the power source is inside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the internal power supply; then, if the power source is outside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the external power supply; further, all internal power supplies and all external power supplies can be obtained by the above method; finally, the set of all internal power supplies can be used as the internal power supply load, and the set of all external power supplies can be used as the external power supply load.

[0030] In some embodiments, determining the load isolation characteristics of the power microgrid in the grid-connected mode by using the external power supply load and the internal power supply load can be implemented by the following steps: determining a temporal correlation between the externally powered load and the internally powered load; Determining the external dependence of the power microgrid in the grid-connected mode according to the external power supply load; The load isolation characteristic of the power microgrid in the grid-connected mode is determined according to the time correlation and the external dependency.

[0031] It should be noted that, in the present application, the load isolation characteristic refers to the power supply independence between the internal load and the external load of the power microgrid. The stronger the load isolation characteristic, the smaller the mutual influence between the internal and external power supply loads of the power microgrid; the time correlation indicates the consistency of the changing trends of the external power supply load and the internal power supply load in the time dimension; the external dependence indicates the degree of dependence of the power microgrid on the power supply of the external power grid.

[0032] In the specific implementation, first, a time series model is initialized, and each external power supply amount and the corresponding collection time in the external power supply load are used as the external power supply parameters in the time series model, and each internal power supply amount and the corresponding collection time in the internal power supply load are used as the internal power supply parameters in the time series model. The time series model is used to perform time correlation analysis on the external power supply load and the internal power supply load, and the correlation coefficient obtained by the time correlation analysis can be used as the time correlation between the external power supply load and the internal power supply load; then, the sum of the external power supply in the external power supply load is used as the external load value, the sum of the internal power supply in the internal power supply load is used as the internal load value, and the sum of the external load value and the internal load value is used as the total load value, and the ratio of the external load value to the total load value can be used as the external dependence of the power microgrid in the grid-connected mode; finally, since the higher the time correlation and external dependence are, the lower the load isolation characteristics are, the inverse of the product of the time correlation and the external dependence can be used as the load isolation characteristics of the power microgrid in the grid-connected mode.

[0033] In step 103, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted based on the distribution load information in combination with the power grid load prediction model, the load margin of the power microgrid in the off-grid mode is determined according to the long-term load and the load isolation characteristics, and the load amplitude of the power microgrid in the off-grid mode is determined by the load margin and the short-term load.

[0034] In some embodiments, based on the distribution load information combined with the grid load forecasting model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted, referring to Figure 3 The figure is a schematic diagram of the process of power grid load prediction in some embodiments of the present application. In this embodiment, the power grid load prediction can be implemented by the following steps: In step 1031, the dispatching load of the power microgrid in the grid-connected mode is determined according to the distribution load information; In step 1032, a load stability value of the power microgrid is determined by the dispatching load and the load isolation characteristic; In step 1033, when the load stability value is lower than the load upper limit of the power microgrid, a power grid load prediction model is constructed according to the power distribution load information; In step 1034, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted based on the grid load prediction model.

[0035] It should be noted that, in this application, short-term load refers to the load demand of the power microgrid in a short period of time (within 1 day by default); long-term load refers to the load demand of the power microgrid in a longer period of time (within 1 month by default); the dispatching load reflects the dispatching amount of internal and external power supply sources of the power microgrid to meet the load demand; the load stability value reflects the ability of the power microgrid to maintain stable power supply between different loads; the load upper limit of the power microgrid refers to the maximum load capacity that the power microgrid can withstand, that is, under normal operating conditions, the maximum power output that the power microgrid can provide to its connected loads. The total power capacity of the power generation equipment, energy storage system, and conversion equipment in the power microgrid can be counted as the load upper limit of the power microgrid.

[0036] In the specific implementation, first, the average value of all distribution quantities in the distribution load information can be used as the dispatching load of the power microgrid in the grid-connected mode; secondly, since , the ratio of the dispatching load and the load isolation characteristic can be used as the load stability value of the power microgrid; then, when the load stability value is less than or equal to the load upper limit of the power microgrid, the current grid-connected mode is maintained, and when the load stability value is lower than the load upper limit of the power microgrid, a power grid load prediction model is initialized, and all load quantities in the distribution load information are used as the training basis of the power grid load prediction model; finally, the trained power grid load prediction model is used to predict the load of the power microgrid in the specified time period in the off-grid mode, and the prediction result of the power microgrid in a short time (default is 1 day) can be used as the recent load, and the prediction result of a longer time (default is 1 month) can be used as the recent load, where the prediction result of the power grid load prediction model is the load quantity for each hour.

[0037] In some embodiments, determining the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristic can be implemented by the following steps: Obtain the internal power supply of the power microgrid in off-grid mode; Determining a power supply capacity of the power microgrid according to the internal power supply amount and the load isolation characteristic; The load margin of the power microgrid in the off-grid mode is determined according to the power supply capacity and the long-term load.

[0038] It should be noted that in this application, the load margin refers to the redundant space of the power supply capacity of the power microgrid exceeding the long-term load demand, reflecting the power margin of the power microgrid under load changes or abnormal conditions. The higher the load margin, the stronger the power supply guarantee of the power microgrid; the power supply capacity refers to the overall power supply guarantee capability of the power microgrid in an isolated operation state.

[0039] In specific implementation, first, the power supply demand of the power microgrid per unit time can be obtained in the dispatching console of the large-scale power grid as the internal power supply of the power microgrid in off-grid mode; then, the product of the internal power supply and the load isolation characteristic can be used as the power supply capacity of the power microgrid; finally, the inverse of the difference between the mean of all loads in the future load and the power supply capacity can be used as the load margin of the power microgrid in off-grid mode.

[0040] It should be noted that load margin is a key indicator for evaluating whether the power microgrid can provide continuous and stable power supply when operating in isolation. Through accurate calculation of power supply capacity and load, the power microgrid can achieve safer and more efficient power dispatching, ensuring that the power microgrid can still maintain stable power supply capacity in the event of future load growth or unexpected situations.

[0041] In some embodiments, determining the load amplitude of the power microgrid in the off-grid mode by using the load margin and the recent load can be implemented by the following steps: Determine the load stability of the power microgrid in off-grid mode; Determining a limit fluctuation value of a load of the power microgrid in an off-grid mode according to the load stability and the load margin; The load amplitude of the power microgrid in the off-grid mode is determined according to the limit fluctuation value and the recent load.

[0042] It should be noted that in this application, the load amplitude represents the recent upper limit of the load of the power microgrid in off-grid mode; load stability refers to the stability ability of the power microgrid in the face of load fluctuations in off-grid mode; the extreme fluctuation value reflects the maximum fluctuation range of the load under different conditions, and the extreme fluctuation value is usually a proportional factor.

[0043] In specific implementation, first, the standard deviation of all loads in the long-term load can be used as the load stability of the power microgrid in the off-grid mode; then, a Monte Carlo simulation model is initialized, the load stability is used as the distribution parameter of the Monte Carlo simulation model, and the load margin is used as the limiting parameter of the load (processing variable) in the Monte Carlo simulation model. The Monte Carlo simulation model is used to simulate the load of the power microgrid in the off-grid mode, and the maximum value of the load fluctuation obtained in multiple simulations can be used as the limit fluctuation value of the load of the power microgrid in the off-grid mode; finally, the sum of the recent load and the limit fluctuation value can be used as the load amplitude of the power microgrid in the off-grid mode.

[0044] It should be noted that the Monte Carlo simulation model is a random simulation model based on probability theory, which is used to evaluate the performance of the system under uncertain conditions. This method can simulate the load fluctuation range of the power microgrid under different load scenarios. In the power microgrid, the Monte Carlo simulation model can be used to simulate different load conditions and fluctuations to calculate the load stability and load margin of the power microgrid. The maximum value of the load fluctuation obtained through multiple simulations is the limit fluctuation value.

[0045] In step 104, when the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode.

[0046] It should be noted that in this application, the load upper limit of the power microgrid refers to the maximum load capacity that the power microgrid can withstand, that is, under normal operating conditions, the maximum power output that the power microgrid can provide for its connected load. The total power capacity of the power generation equipment, energy storage system, and conversion equipment in the power microgrid can be counted as the load upper limit of the power microgrid.

[0047] In some embodiments, automatically switching the dispatching mode of a power microgrid in a large-scale power grid from a grid-connected mode to an off-grid mode may be achieved by the following steps: Disconnecting microgrids from the large-scale grid; Start the independent operation mode of the power microgrid and complete the automatic switching from grid-connected mode to off-grid mode.

[0048] In specific implementation, first, circuit breakers or power electronic devices are used to cut off the physical connection between the power microgrid and the large-scale power grid (grid-connected mode) within milliseconds to ensure stable switching of the system; then, the power generation equipment and energy storage system inside the power microgrid begin to independently supply power to the load, switch to independent operation mode, and monitor the internal voltage, frequency and other indicators of the power microgrid in real time to complete the automatic switching from grid-connected mode to off-grid mode.

[0049] In the present application, when the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode; first, the determination of the load isolation characteristic is based on the analysis of the internal power supply load and the external power supply load. Through the evaluation of time correlation and external dependence, the independence of the power microgrid in the grid-connected mode can be quantified. The load isolation characteristic determines whether the power microgrid can maintain stable operation in the face of external power grid fluctuations and under what conditions it can achieve independent operation (off-grid mode). The stronger the load isolation characteristic, the less dependent the power microgrid is on external power supply, which helps to reduce the impact of external fluctuations on the internal system and improve the independent operation capability and energy utilization efficiency of the power microgrid; then, the determination of the load amplitude depends on the calculation of the load margin and the recent load. The load amplitude reflects the load fluctuation range that the power microgrid can withstand in the off-grid mode. Through reasonable amplitude management, the power microgrid can maintain stable operation when the load fluctuates, which not only avoids excessive energy consumption, but also ensures the optimal configuration of energy. When the load amplitude is lower than the load upper limit of the power microgrid, the power microgrid can be automatically switched to off-grid mode, thereby making full use of the internal resources of the power microgrid and reducing the power microgrid's dependence on the external power grid; in summary, based on the above scheme, the automatic switching of the dispatching mode of the power microgrid in the large-scale power grid can be realized, thereby improving the energy utilization rate in the power microgrid.

[0050] In addition, in another aspect of the present application, in some embodiments, the present application provides an intelligent power supply and distribution management system for a large-scale power grid, and the intelligent power supply and distribution management system for a large-scale power grid also includes a scheduling mode switching unit, referring to Figure 4 , which is a schematic diagram of the structure of exemplary hardware and / or software of a scheduling mode switching unit according to some embodiments of the present application, and the scheduling mode switching unit includes: a collection module 201, a processing module 202 and an execution module 203, which are described as follows: The acquisition module 201 in this application is mainly used to collect historical power supply information and distribution load information of the power microgrid within a specified time period; Processing module 202, in the present application, the processing module 202 is used to divide the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determine the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; It should be noted that the processing module 202 is also used to predict the recent load and long-term load of the power microgrid in the off-grid mode based on the distribution load information combined with the grid load prediction model, determine the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristics, and determine the load amplitude of the power microgrid in the off-grid mode according to the load margin and the recent load; Execution module 203, in the present application, execution module 203 is mainly used to automatically switch the dispatching mode of the power microgrid in the large-scale power grid from the grid-connected mode to the off-grid mode when the load amplitude is lower than the load upper limit of the power microgrid.

[0051] The above describes in detail the examples of the intelligent power supply and distribution management system and method for large-scale power grids provided by the embodiments of the present application. It can be understood that in order to realize the above functions, the corresponding device includes hardware structures and / or software modules corresponding to the execution of each function. It should be easily appreciated by those skilled in the art that, in combination with the units and algorithm steps of each example described in the embodiments disclosed herein, the present application can be implemented in the form of hardware or a combination of hardware and computer software. Whether a function is executed in the form of hardware or computer software driving hardware depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of the present application.

[0052] In some embodiments, the present application also provides a computer device, comprising a memory and a processor, wherein the memory is used to store a computer program, and the processor is used to call and run the computer program from the memory, so that the computer device executes the above-mentioned method for switching the dispatching mode of a power microgrid in a large-scale power grid.

[0053] In some embodiments, reference Figure 5 , the dotted line in the figure indicates that the unit or the module is optional, and the figure is a structural diagram of a computer device for implementing a method for switching a dispatching mode of a power microgrid in a large-scale power grid according to an embodiment of the present application. The method for switching a dispatching mode of a power microgrid in a large-scale power grid described in the above embodiment can be Figure 5 The computer device shown in the figure is implemented, and the computer device includes at least one processor 301, a memory 302 and at least one communication unit 305. The computer device can be a terminal device, a server or a chip.

[0054] The processor 301 may be a general-purpose processor or a special-purpose processor. For example, the processor 301 may be a central processing unit (CPU), which may be used to control the computer device, execute software programs, and process data of the software programs. The computer device may also include a communication unit 305 to implement signal input (reception) and output (transmission).

[0055] For example, the computer device may be a chip, the communication unit 305 may be an input and / or output circuit of the chip, or the communication unit 305 may be a communication interface of the chip, and the chip may be a component of a terminal device, a network device, or other devices.

[0056] For another example, the computer device may be a terminal device or a server, and the communication unit 305 may be a transceiver of the terminal device or the server, or the communication unit 305 may be a transceiver circuit of the terminal device or the server.

[0057] The computer device may include one or more memories 302, on which a program 304 is stored. The program 304 can be executed by the processor 301 to generate instructions 303, so that the processor 301 performs the method described in the above method embodiment according to the instructions 303. Optionally, data (such as a target audit model) can also be stored in the memory 302. Optionally, the processor 301 can also read the data stored in the memory 302, and the data can be stored at the same storage address as the program 304, or the data can be stored at a different storage address from the program 304.

[0058] The processor 301 and the memory 302 may be provided separately or integrated together, for example, integrated on a system on chip (SOC) of the terminal device.

[0059] It should be understood that each step of the above method embodiment can be completed by a hardware-based logic circuit or software-based instructions in the processor 301. The processor 301 can be a CPU, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field programmable gate array (FPGA), or other programmable logic devices, such as discrete gates, transistor logic devices, or discrete hardware components.

[0060] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment combining software and hardware. Moreover, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program codes.

[0061] For example, in some embodiments, the present application also provides a computer-readable storage medium, in which instructions or codes are stored. When the instructions or codes are executed on a computer, the computer implements the above-mentioned method for switching the dispatching mode of a power microgrid in a large-scale power grid when executing the computer.

[0062] Although the preferred embodiments of the present application have been described, those skilled in the art may make other changes and modifications to these embodiments once they have learned the basic creative concept. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications falling within the scope of the present application.

[0063] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.

Claims

1. A method for switching the dispatching mode of a power microgrid in a large-scale power grid, used for switching the dispatching mode of an intelligent power supply and distribution management system, characterized in that: The steps include: Monitor the power microgrid in the grid-connected mode of the large-scale power grid, and collect the historical power supply information and distribution load information of the power microgrid within a specified time period; Dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determining the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; Based on the distribution load information and the grid load prediction model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted; the load margin of the power microgrid in the off-grid mode is determined according to the long-term load and the load isolation characteristic; and the load amplitude of the power microgrid in the off-grid mode is determined according to the load margin and the short-term load; When the load amplitude is lower than the load upper limit of the power microgrid, the dispatching mode of the power microgrid in the large-scale power grid is automatically switched from the grid-connected mode to the off-grid mode.

2. The method according to claim 1, characterized in that Dividing the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid specifically includes: For each power supply source in the power microgrid, the power source of the power supply source is determined according to the access mode of the power supply source; If the power source is inside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the internal power supply; If the power source is outside the power microgrid, the power supply of the power supply source in the historical power supply information is used as the external power supply; Then all internal power supplies and all external power supplies are obtained; The internal power supply load is determined based on all internal power supplies, and the external power supply load is determined based on all external power supplies.

3. The method according to claim 1, characterized in that Determining the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply load and the internal power supply load specifically includes: determining a temporal correlation between the externally powered load and the internally powered load; Determining the external dependence of the power microgrid in the grid-connected mode according to the external power supply load; The load isolation characteristic of the power microgrid in the grid-connected mode is determined according to the time correlation and the external dependency.

4. The method according to claim 1, characterized in that Predicting the short-term load and long-term load of the power microgrid in the off-grid mode based on the distribution load information combined with the grid load prediction model specifically includes: Determine the dispatching load of the power microgrid in the grid-connected mode according to the distribution load information; Determining a load stability value of the power microgrid by using the dispatching load and the load isolation characteristic; When the load stability value is lower than the load upper limit of the power microgrid, constructing a power grid load prediction model according to the power distribution load information; Based on the grid load prediction model, the short-term load and long-term load of the power microgrid in the off-grid mode are predicted.

5. The method according to claim 1, characterized in that Determining the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristic specifically includes: Obtain the internal power supply of the power microgrid in off-grid mode; Determining a power supply capacity of the power microgrid according to the internal power supply amount and the load isolation characteristic; The load margin of the power microgrid in the off-grid mode is determined according to the power supply capacity and the long-term load.

6. The method according to claim 1, characterized in that Determining the load amplitude of the power microgrid in the off-grid mode by using the load margin and the recent load specifically includes: Obtaining load stability of power microgrid in off-grid mode; Determining a limit fluctuation value of a load of the power microgrid in an off-grid mode according to the load stability and the load margin; The load amplitude of the power microgrid in the off-grid mode is determined according to the limit fluctuation value and the recent load.

7. The method according to claim 1, characterized in that The large-scale power grid is a 750kV AC power transmission network based on wind power generation.

8. An intelligent power supply and distribution management system for a large-scale power grid, the intelligent power supply and distribution management system for a large-scale power grid comprising a dispatching mode switching unit, characterized in that: The scheduling mode switching unit comprises: A collection module is used to collect historical power supply information and distribution load information of the power microgrid within a specified time period; A processing module, used to divide the historical power supply information into internal power supply loads and external power supply loads according to the access mode of each power supply source in the power microgrid, and determine the load isolation characteristics of the power microgrid in the grid-connected mode through the external power supply loads and the internal power supply loads; The processing module is also used to predict the short-term load and long-term load of the power microgrid in the off-grid mode based on the distribution load information combined with the power grid load prediction model, determine the load margin of the power microgrid in the off-grid mode according to the long-term load and the load isolation characteristic, and determine the load amplitude of the power microgrid in the off-grid mode according to the load margin and the short-term load; The execution module is used to automatically switch the dispatching mode of the power microgrid in the large-scale power grid from the grid-connected mode to the off-grid mode when the load amplitude is lower than the load upper limit of the power microgrid.

9. A computer device, characterized in that: The computer device includes a memory and a processor, the memory is used to store a computer program, and the processor is used to call and run the computer program from the memory, so that the computer device executes the dispatch mode switching method of a power microgrid in a large-scale power grid as described in any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions or codes, and when the instructions or codes are executed on a computer, the computer implements the method for switching the dispatching mode of a power microgrid in a large-scale power grid as described in any one of claims 1 to 7.

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