Micro-grid group user energy storage demand quantification analysis method and system

Abstract

The application discloses a micro-grid group user energy storage demand quantitative analysis method and system, belongs to the technical field of power system user side energy storage planning and demand analysis, solves the problem that the existing micro-grid group user energy storage demand analysis method does not consider quantitative analysis of multiple targets and multiple operation modes, and the method comprises the following steps: obtaining typical daily net load curves of each micro-grid in the micro-grid group, calculating the difference between the load and new energy output at each time, and identifying new energy consumption pressure intervals and reliable power supply pressure intervals; superimposing the net load curves to determine the energy storage complementary window; taking the economy, environmental protection and power supply reliability optimization as the target, respectively constructing energy storage demand analysis models in the independent and shared modes, and quantitatively obtaining the energy storage capacity and power demand values; comparing the demand critical values under different target combinations to obtain the first energy storage comprehensive demand value of the micro-grid user and the second energy storage comprehensive demand value of the micro-grid group user; and the application is applied to the micro-grid.

Description

Technical Field

[0001] This invention relates to the field of power system user-side energy storage planning and demand analysis technology, specifically to a method and system for quantitative analysis of energy storage demand of microgrid users. Background Technology

[0002] With the continuous advancement of new power system construction, microgrids containing distributed photovoltaic power are being widely deployed in industrial parks, park-level distribution networks, and other scenarios. Multiple neighboring microgrids are often interconnected through upper-level distribution networks or dedicated lines to form "microgrid clusters." Against this backdrop, microgrid cluster users face a series of questions, including whether to configure energy storage, how to determine the storage capacity, and which investment and operation model to choose. Currently, there is a lack of directly quantifiable decision-making criteria, which restricts the scientific planning and efficient utilization of energy storage systems in microgrid clusters.

[0003] To meet the flexible electricity demands of microgrid clusters, users' energy storage configurations exhibit multi-objective characteristics: they aim to reduce electricity purchase costs and capacity fees through peak-valley electricity price arbitrage, reduce carbon emissions by increasing the local consumption rate of renewable energy, and ensure the reliability of power supply to critical loads during grid failures or islanded operation. Therefore, how to coordinate economic, environmental, and reliability objectives and develop a quantitative analysis method that can directly output the boundaries of energy storage power and capacity demand has become a critical issue that urgently needs to be addressed in microgrid cluster engineering practice.

[0004] Currently, research in the field of energy storage planning and operation is mostly focused on the system side, primarily revolving around the selection, capacity optimization, and life-cycle economic evaluation of energy storage in a single microgrid or distribution network. For example, optimization models aimed at peak shaving, valley filling, reducing the cost of curtailment of solar and wind power, or improving power supply reliability are used to determine energy storage configuration schemes; or comparisons of the economic characteristics of different energy storage technologies provide a reference for type selection. While these studies have some guiding significance, they are mostly limited to the scope of a single system, failing to fully reflect the characteristics of multi-microgrid collaborative operation and complementary source-load characteristics within a microgrid cluster, and lacking a systematic method for deriving energy storage capacity from the actual needs of users.

[0005] As microgrids evolve towards clustering, some research has begun to focus on issues such as the collaborative operation of multiple microgrids and shared energy storage operation models. For example, it analyzes the revenue differences of energy storage projects under different business models, or explores optimized operation strategies for microgrid clusters primarily aimed at promoting renewable energy consumption. However, existing work focuses more on "how to utilize existing energy storage to improve system efficiency," while research on "how much energy storage is actually needed on the user side" and "demand differences under different investment models" is insufficient. A quantitative energy storage demand analysis method that considers multiple objectives and covers both independent and shared operation models has not yet been developed. Summary of the Invention

[0006] To address the technical problems that existing methods for analyzing the energy storage demand of microgrid users do not take into account multi-dimensional objectives and do not cover both independent and shared operation modes for quantitative analysis of energy storage demand, thus hindering the scientific planning and efficient utilization of microgrid energy storage systems, this invention proposes a method and system for quantitative analysis of energy storage demand of microgrid users.

[0007] To solve the above-mentioned technical problems, the technical solution adopted by the present invention is: a method for quantitative analysis of energy storage demand of microgrid users, comprising the following steps:

[0008] Step S1: Obtain multiple typical days representing different operating characteristics of each microgrid in the microgrid group;

[0009] Step S2: Obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, obtain the difference between the load demand and the output of new energy sources for each microgrid at each time.

[0010] Step S3: Identify the new energy absorption pressure range and reliable power supply pressure range of the microgrid based on the difference between load demand and new energy output at each time.

[0011] Step S4: Overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy absorption pressure and reliable power supply pressure between pairs of microgrids, and identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group.

[0012] Step S5: Based on the pressure range of new energy consumption, the pressure range of reliable power supply, and the energy storage complementarity window range for sharing and utilization by microgrid users, with the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, we construct quantitative analysis models of energy storage demand for microgrid users and energy storage demand for microgrid users respectively, so as to obtain the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid users under the corresponding objectives.

[0013] Step S6: Compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations to obtain the first comprehensive energy storage demand value of microgrid users under the corresponding target combinations; compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection to obtain the second comprehensive energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

[0014] Furthermore, the quantitative analysis model for microgrid user energy storage demand includes a quantitative analysis model for microgrid user energy storage capacity demand and a quantitative analysis model for microgrid user power demand.

[0015] The quantitative analysis model for energy storage demand of microgrid users includes a quantitative analysis model for energy storage capacity demand of microgrid users and a quantitative analysis model for power demand of microgrid users.

[0016] Furthermore, in step S5, the process of constructing a quantitative analysis model of energy storage demand for microgrid users and a quantitative analysis model of energy storage demand for microgrid cluster users, with optimal economic efficiency as the core objective, is as follows:

[0017] Based on the constraint of maximizing peak-valley arbitrage profits for single microgrids and microgrid clusters, and combined with the analysis results of the upper limit of charging power during valley hours and the upper limit of discharging power during peak hours, we construct quantitative analysis models of energy storage demand for microgrid users and microgrid cluster users with the goal of economic optimization, respectively. We obtain the energy storage capacity and energy storage power demand of microgrid users with the goal of economic optimization, as well as the energy storage capacity and energy storage power demand of microgrid cluster users with the goal of economic optimization.

[0018] Furthermore, in step S5, the process of constructing a quantitative analysis model of energy storage demand for microgrid users and a quantitative analysis model of energy storage demand for microgrid cluster users, with optimal environmental protection as the core objective, is as follows:

[0019] Based on the constraint relationship between the local consumption rate of new energy and the required energy storage capacity, we construct quantitative analysis models for energy storage demand of microgrid users with the goal of optimal environmental protection and microgrid group users with the goal of optimal environmental protection, respectively. We obtain the required energy storage capacity and required energy storage power of microgrid users with the goal of optimal environmental protection, as well as the required energy storage capacity and required energy storage power of microgrid group users with the goal of optimal environmental protection.

[0020] Furthermore, in step S5, the process of constructing a quantitative analysis model of energy storage demand for microgrid users and a quantitative analysis model of energy storage demand for microgrid cluster users, with optimal power supply reliability as the core objective, is as follows:

[0021] By identifying the source-load imbalance intervals in the operation of microgrid users and quantifying their key characteristics, including at least area and peak value, a demand-energy storage capacity model and a demand-energy storage power value model with the goal of optimal power supply reliability are constructed. The lower limits of the demand-energy storage capacity and demand-energy storage power value are then derived to ensure that microgrid users do not experience power outages during emergency support phases.

[0022] Furthermore, in step S5, the constraint relationship for maximizing peak-valley arbitrage profits of the microgrid is expressed in terms of demand storage capacity as follows:

[0023] During off-peak electricity pricing periods, microgrid users should charge their energy storage devices as much as possible, but the charging power should be less than the sum of the microgrid's transmission channel power and the microgrid's renewable energy redundancy power.

[0024] During peak electricity price periods, microgrid users should discharge as much as possible, but to avoid power flow back, the discharge power of the microgrid should be less than the net load power of the microgrid.

[0025] At the same time, ensure that the total charging and discharging power of a single microgrid remains constant throughout the day, so as to guarantee the balance of the final state of energy storage for microgrid users;

[0026] The constraint on maximizing peak-valley arbitrage profits in microgrids is expressed in terms of demand storage power as follows:

[0027] The maximum charging rate of energy storage for microgrid users should be greater than the sum of the maximum line transmission power and the surplus power of new energy sources during off-peak electricity price periods, and the maximum discharging power of energy storage for microgrid users should be greater than the maximum net load power during peak electricity price periods, so as to ensure that the charging and discharging rate of energy storage for microgrid users does not lead to a waste of its capacity.

[0028] The constraint on maximizing peak-valley arbitrage profits in microgrid clusters is manifested in terms of demand storage capacity as follows:

[0029] On the user side of a microgrid cluster, the energy storage discharge power must not exceed the sum of the net loads of each microgrid.

[0030] Furthermore, the constraint relationship between the local consumption rate of new energy and the demand for energy storage capacity is as follows:

[0031] On a daily timescale, the maximum charging power of energy storage for microgrid users should be greater than the maximum excess power of photovoltaic power; the energy storage capacity required by microgrid users should not be less than the preset value of daily absorption rate.

[0032] On an annual timescale, the pressure range of renewable energy consumption on typical days is comprehensively considered to ensure that the energy storage capacity required by microgrid users can meet the requirement that the renewable energy consumption rate is not lower than the minimum annual consumption rate limit on an annual timescale.

[0033] Furthermore, the optimal power supply reliability requires that the maximum discharge power of the energy storage of a single microgrid user must be greater than the instantaneous power deficit of the single microgrid user.

[0034] The energy storage capacity required by a single microgrid user is greater than the maximum value of the rolling integral of the power within the reliable power supply pressure range for each time period.

[0035] Furthermore, the pressure range for renewable energy absorption is the range where renewable energy output exceeds load demand, and the pressure range for reliable power supply is the range where load demand exceeds available power supply capacity.

[0036] A microgrid cluster user energy storage demand quantification analysis system, used to implement the steps of the above-described method, including:

[0037] The data acquisition and input unit is used to acquire multiple typical days representing different operating characteristics of each microgrid in the microgrid group;

[0038] The source-load matching analysis unit is connected to the data acquisition and input unit to obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, the difference between the load demand and the output of new energy sources for each microgrid at each moment is obtained.

[0039] The pressure zone identification unit is connected in communication with the source-load matching analysis unit. It is used to identify the new energy consumption pressure zone and the reliable power supply pressure zone of the microgrid based on the difference between the load demand and the new energy output at each time.

[0040] The energy storage complementary window interval identification unit is connected in communication with the source-load matching analysis unit. It is used to overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy consumption pressure and reliable power supply pressure between two microgrids and identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group.

[0041] The energy storage demand quantification unit is communicatively connected to the pressure range identification unit and the energy storage complementarity window range identification unit. The energy storage demand quantification unit is used to construct energy storage demand quantification analysis models for microgrid users and microgrid group users based on the new energy consumption pressure range, reliable power supply pressure range, and energy storage complementarity window range shared by microgrid group users. With the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, the energy storage demand quantification analysis model for microgrid users and microgrid group users is constructed respectively, thereby obtaining the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid group users under the corresponding objectives.

[0042] The integrated demand quantification unit, which communicates with the energy storage demand quantification unit, is used to compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations, so as to obtain the first integrated energy storage demand value of microgrid users under the corresponding target combinations; and to compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection, so as to obtain the second integrated energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

[0043] The advantages of this invention over the prior art are as follows:

[0044] 1. This invention integrates three core objectives: optimal economy, optimal environmental protection, and optimal power supply reliability. It constructs quantitative analysis models for energy storage demand of microgrid users and microgrid cluster users, respectively, to obtain the energy storage capacity and power demand values ​​of microgrid users and microgrid cluster users under the corresponding objectives. It fully considers the differences and complementarities of the source and load characteristics of multiple microgrids in the microgrid cluster, and quantifies the comprehensive energy storage demand of the user side under the shared energy storage mode adopted by the microgrid cluster.

[0045] 2. This invention obtains the first comprehensive energy storage demand value of microgrid users under different target combinations by comparing and analyzing the critical values ​​of the first demand energy storage capacity and the first demand energy storage power value obtained by microgrid users under different target combinations; it also obtains the second comprehensive energy storage demand value of microgrid users under the two target combinations of optimal economy and optimal environmental protection by comparing and analyzing the critical values ​​of the second demand energy storage capacity and the second demand energy storage power value obtained by microgrid users under the two target combinations of optimal economy and optimal environmental protection, thus forming an energy storage demand analysis method that takes into account multiple dimensions and provides critical values ​​for both independent and shared operation modes. Attached Figure Description

[0046] The present invention will be further described below with reference to the accompanying drawings:

[0047] Figure 1 This is a schematic flowchart of the method of the present invention;

[0048] Figure 2 This is a schematic diagram illustrating the quantitative range of new energy absorption pressure and reliable power supply pressure in a microgrid according to an embodiment of the present invention.

[0049] Figure 3 This is a schematic diagram illustrating the quantitative range of new energy absorption pressure and reliable power supply pressure in a microgrid according to an embodiment of the present invention.

[0050] Figure 4 This is a schematic diagram illustrating the quantitative range of the three new energy absorption pressures and reliable power supply pressures of a microgrid according to an embodiment of the present invention;

[0051] Figure 5 This is a schematic diagram illustrating the overall source-load power matching of a microgrid group comprising microgrid 1, microgrid 2, and microgrid 3, according to an embodiment of the present invention.

[0052] Figure 6 This is a schematic diagram of the system of the present invention. Detailed Implementation

[0053] In the description of this invention, it should be understood that the terms "center," "longitudinal," "lateral," "upper," "lower," "front," "rear," "left," "right," "vertical," "horizontal," "top," "bottom," "inner," and "outer," etc., indicate relative orientations or positional relationships and are used only for the convenience of describing the invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of the invention. Furthermore, the terms "first," "second," etc., are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of indicated technical features. Thus, a feature defined with "first," "second," etc., may explicitly or implicitly include one or more of that feature. In the description of this invention, unless otherwise stated, "a plurality of" means two or more.

[0054] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "installation," "connection," and "linking" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art will understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0055] like Figures 1 to 6 As shown, this invention provides a method for quantitative analysis of energy storage demand of microgrid users, including the following steps:

[0056] Step S1: Obtain multiple typical days representing different operating characteristics of each microgrid in the microgrid group.

[0057] Specifically, the following steps are included:

[0058] Step S11: Obtain the microgrid group topology. The microgrid group topology includes at least several microgrids, the upper-level distribution network, and independent energy storage units and shared energy storage units configured as needed. Obtain basic data such as the predicted load of each microgrid, the predicted power generation of distributed new energy sources, the electricity price curve, and the line transmission capacity.

[0059] Step S12: Obtain multiple typical days representing different operating characteristics of each microgrid, such as quarters, weekdays / weekends, and operating conditions; analyze the frequency of occurrence of each typical day based on the pre-stored annual statistical data of different operating characteristics to reflect the annual operating characteristics of the microgrid group users.

[0060] Step S2: Obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, obtain the difference between the load demand and the output of new energy sources for each microgrid at each time.

[0061] Step S3: Identify the renewable energy absorption pressure range and the reliable power supply pressure range of the microgrid based on the difference between load demand and renewable energy output at each time point. The renewable energy absorption pressure range is the range where renewable energy output exceeds load demand, and the reliable power supply pressure range is the range where load demand exceeds available power supply capacity.

[0062] Step S4: Overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy absorption pressure and reliable power supply pressure between pairs of microgrids, and identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group.

[0063] Step S5: Based on the pressure range of new energy consumption, the pressure range of reliable power supply, and the energy storage complementarity window range for microgrid users to share and utilize, with the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, respectively construct a quantitative analysis model of energy storage demand for microgrid users and a quantitative analysis model of energy storage demand for microgrid users, thereby obtaining the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid users under the corresponding objectives.

[0064] The quantitative analysis model for microgrid user energy storage demand includes a quantitative analysis model for microgrid user energy storage capacity demand and a quantitative analysis model for microgrid user power demand.

[0065] The quantitative analysis model for energy storage demand of microgrid users includes a quantitative analysis model for energy storage capacity demand of microgrid users and a quantitative analysis model for power demand of microgrid users.

[0066] In step S5, with optimal economic efficiency as the core objective, the process of constructing quantitative analysis models for energy storage demand of microgrid users and microgrid cluster users is as follows:

[0067] Based on the constraint of maximizing peak-valley arbitrage profits for single microgrids and microgrid clusters, and combined with the analysis results of the upper limit of charging power during valley hours and the upper limit of discharging power during peak hours, we construct quantitative analysis models of energy storage demand for microgrid users and microgrid cluster users with the goal of economic optimization, respectively. We obtain the energy storage capacity and energy storage power demand of microgrid users with the goal of economic optimization, as well as the energy storage capacity and energy storage power demand of microgrid cluster users with the goal of economic optimization.

[0068] The constraint on maximizing peak-valley arbitrage profits in microgrids is manifested in terms of demand storage capacity as follows:

[0069] During off-peak electricity pricing periods, microgrid users should charge their energy storage devices as much as possible, but the charging power should be less than the sum of the power of the microgrid transmission channel and the redundant power of the microgrid's renewable energy sources.

[0070] During peak electricity price periods, microgrid users should discharge as much as possible, but to avoid power flow back, the discharge power of the microgrid should be less than the net load power of the microgrid.

[0071] At the same time, ensure that the overall charging and discharging power of a single microgrid remains constant throughout the day, so as to guarantee the balance of the final state of energy storage for microgrid users.

[0072] The quantitative analysis model for the energy storage capacity demand of microgrid users with the goal of optimal economic efficiency is as follows:

[0073] ;

[0074] In the above formula, This represents the energy storage capacity demand of microgrid users with the goal of optimal economic efficiency. The subscript "dis" indicates that the variable belongs to a single microgrid user, and the same applies below. , These represent the maximum and minimum SOC (State of Charge) capacity values ​​for energy storage of microgrid users, respectively. This represents the ratio between the SOC capacity of a microgrid user's energy storage and its rated capacity, and is determined by factors such as the type of energy storage selected. , , These represent the energy storage SOC capacity, charging power, and discharging power during time period t, respectively. , These represent the charging and discharging efficiencies of energy storage for microgrid users, respectively. , These represent the time sets for peak and off-peak electricity prices, respectively.

[0075] The constraint on maximizing peak-valley arbitrage profits in microgrids is expressed in terms of demand storage power as follows:

[0076] The maximum charging rate of energy storage for microgrid users should be greater than the sum of the maximum line transmission power and the surplus power of new energy sources during off-peak electricity price periods, and the maximum discharging power of energy storage for microgrid users should be greater than the maximum net load power during peak electricity price periods, so as to ensure that the charging and discharging rate of energy storage for microgrid users does not lead to a waste of its capacity.

[0077] The quantitative analysis model for microgrid user power demand with the goal of optimal economic efficiency is as follows:

[0078] ;

[0079] In the above formula, This represents the maximum transmission power of the microgrid user's transmission line; This represents the output power of the new energy source during time period t; Indicates the load power during time period t; "" indicates an upward approximation operation.

[0080] The constraint on maximizing peak-valley arbitrage profits in microgrid clusters is manifested in terms of demand storage capacity as follows:

[0081] For microgrid users connected to the distribution network, the required capacity of shared energy storage for microgrid users is quantified. The operating rules are set as follows: on the distribution network side, due to ample transmission capacity, the charging power of energy storage is less restricted under the peak-valley pricing mechanism; however, on the microgrid user side, the discharging power of energy storage must ensure power supply within the microgrid user group and must not exceed the sum of the net loads of each microgrid. Based on this constraint, the quantitative analysis model for the energy storage capacity requirement of microgrid users, with optimal economic efficiency as the objective, is as follows:

[0082] ;

[0083] In the above formula, This represents the energy storage capacity demanded by microgrid users with the goal of optimal economic efficiency. , These represent the maximum and minimum SOC (State of Charge) capacity values ​​for energy storage users in a microgrid group, respectively. This represents the ratio between the SOC capacity of the energy storage users in a microgrid group and the rated capacity, which is determined by factors such as the type of energy storage selected. , , These represent the energy storage SOC capacity, charging power, and discharging power during time period t, respectively. , These represent the charging and discharging efficiencies of energy storage for users in a microgrid group, respectively. , These represent the time sets for peak and off-peak electricity prices, respectively.

[0084] The quantitative analysis model for the power demand of microgrid users with the goal of optimal economic efficiency is as follows:

[0085] ;

[0086] ;

[0087] In the above formula, This represents the set of all microgrid users; , These represent the load power and renewable energy generation power of a single microgrid user i during time period t, respectively. This indicates the number of time periods during which the stored energy is discharged.

[0088] In step S5, with optimal environmental performance as the core objective, the process of constructing quantitative analysis models for energy storage demand of microgrid users and microgrid cluster users is as follows:

[0089] Based on the constraint relationship between the local consumption rate of new energy and the required energy storage capacity, we construct quantitative analysis models for energy storage demand of microgrid users with the goal of optimal environmental protection and microgrid group users with the goal of optimal environmental protection, respectively. We obtain the required energy storage capacity and required energy storage power of microgrid users with the goal of optimal environmental protection, as well as the required energy storage capacity and required energy storage power of microgrid group users with the goal of optimal environmental protection.

[0090] The constraint relationship between the local consumption rate of new energy and the demand for energy storage capacity is as follows:

[0091] On a daily timescale, the maximum charging power of energy storage for microgrid users should be greater than the maximum excess power of photovoltaic power; the energy storage capacity required by microgrid users should not be less than the preset value of daily absorption rate.

[0092] On an annual timescale, the pressure range of renewable energy consumption on typical days is comprehensively considered to ensure that the energy storage capacity required by microgrid users can meet the requirement that the renewable energy consumption rate is not lower than the minimum annual consumption rate limit on an annual timescale.

[0093] Specifically, this refers to the independent investment model adopted by microgrid users:

[0094] On a daily timescale, the constraint relationship between the local renewable energy consumption rate and the required energy storage capacity for microgrid users is expressed in terms of required energy storage power as follows:

[0095] The maximum charging power of energy storage for microgrid users should be greater than the maximum excess power of photovoltaic power.

[0096] The quantitative analysis model for microgrid user power demand with the goal of optimal environmental protection is as follows:

[0097] ;

[0098] In the above formula, This represents the required charging power for energy storage of microgrid users with the goal of optimal environmental performance. The subscript "dis" indicates that the variable belongs to a single microgrid, and the same applies below. This represents the output power of new energy sources within the microgrid during a typical day t. This represents the load power of a microgrid user during a typical day t period; Represents a typical day set; This represents the time set where typical microgrid users face pressure to absorb renewable energy.

[0099] On a daily timescale, the constraint relationship between the local renewable energy consumption rate and the required energy storage capacity for microgrid users is expressed as follows:

[0100] The energy storage capacity required by microgrid users should not be less than the preset daily consumption rate. The basic idea is as follows: Figure 2 As shown, the area of ​​the renewable energy absorption pressure zone for microgrid users on each typical day represents the excess electricity resulting from the inability of distributed renewable energy to be absorbed locally. This corresponds to the energy storage capacity configuration requirement for microgrid users—the required energy storage capacity for microgrid users should be greater than the area of ​​the renewable energy absorption pressure zone. Based on this idea, a quantitative analysis model for the energy storage capacity requirement of microgrid users, with optimal environmental performance as the objective, is determined on a daily time scale as follows:

[0101] ;

[0102] In the above formula, This represents the energy storage capacity required by microgrid users with the goal of optimal environmental performance on a daily timescale. This represents the initial SOC capacity of microgrid user demand energy storage at the beginning of the absorption pressure range on the d-th typical day, with the goal of optimal environmental performance. This represents the proportion of power absorbed by energy storage for microgrid users with optimal environmental performance on the d-th typical day, relative to the excess power of new energy sources; "Pr" indicates probability confidence calculation. This represents the percentage of the minimum daily absorption rate of new energy sources. This represents the time set of the d-th typical day; This indicates the minimum required confidence level.

[0103] On an annual timescale, the constraint relationship between the local renewable energy consumption rate and the required energy storage capacity for microgrid users is expressed in terms of required energy storage power as follows:

[0104] Taking into account the renewable energy absorption pressure range of each typical day, the energy storage capacity required by microgrid users is ensured to meet the minimum annual absorption rate limit on an annual time scale. Considering the temporal correlation between multiple typical days, the energy storage SOC capacity at the initial moment of the absorption pressure range in each typical day needs to be corrected. The basic idea is: if photovoltaic power is charged during the photovoltaic surplus period of a certain typical day, the minimum energy storage SOC capacity at the initial moment of the photovoltaic surplus period in the next typical day can be determined by assuming that the microgrid user's energy storage will remain in a discharging state for a period of time thereafter and calculating the maximum discharge amount. Based on this idea, the quantitative analysis model for the energy storage capacity demand of microgrid users with optimal environmental protection as the goal is determined on an annual time scale as follows:

[0105] ;

[0106] In the above formula, This represents the energy storage capacity demand of microgrid users with the goal of optimal environmental performance on an annual timescale. This represents the SOC capacity of the energy storage system at the end of each typical daytime pressure absorption period; This represents the renewable energy consumption rate for each typical day; This represents the time set during which there is no pressure to absorb new energy sources between two typical days (e.g., Figure 2 (as shown) This represents the minimum renewable energy absorption rate limit for microgrid users on an annual timescale.

[0107] Based on the above analysis, the energy storage power and capacity requirements for microgrid users, with optimal environmental performance as the goal, can be derived as follows:

[0108] .

[0109] Specifically, this refers to the shared investment model adopted by microgrid users:

[0110] On a daily timescale, this paper analyzes and quantifies the energy storage demand of microgrid users based on low-carbon and environmental protection requirements. The quantitative analysis model for the power demand of microgrid users, with optimal environmental performance as the goal, is as follows:

[0111] ;

[0112] In the above formula, This represents the charging power required for energy storage by users in a microgrid cluster with the goal of optimal environmental performance. This represents the collection of microgrids; , These represent the load power and renewable energy generation power of a single microgrid i during time period t on a typical day d.

[0113] The quantitative analysis model for the energy storage capacity demand of microgrid users with the goal of optimal environmental protection on a daily time scale is as follows:

[0114] ;

[0115] In the above formula, This represents the energy storage capacity demand of microgrid users with the goal of optimal environmental performance on a daily timescale. This represents the initial SOC capacity of energy storage at the beginning of the absorption pressure range on the d-th typical day; This represents the proportion of the power absorbed by user i of a single microgrid with energy storage on the dth typical day to its excess renewable energy power. This represents the proportion of the minimum daily renewable energy consumption rate for users in a microgrid group. This represents the time set of the d-th typical day.

[0116] The quantitative analysis model for the energy storage capacity demand of microgrid users with the goal of optimal environmental protection on an annual timescale is as follows:

[0117]

[0118] In the above formula, This represents the energy storage capacity demand of microgrid users with the goal of optimal environmental performance on an annual timescale. This represents the SOC capacity of energy storage at the end of the pressure absorption period on the d-th typical day; This represents the renewable energy consumption rate for each typical day; This represents the time set during which there is no pressure to absorb new energy sources between two typical days; This indicates the minimum annual consumption ratio of new energy sources in a microgrid cluster.

[0119] Based on the above analysis, the energy storage power and capacity requirements for microgrid users, with optimal environmental performance as the goal, can be derived as follows:

[0120] .

[0121] In step S5, with optimal power supply reliability as the core objective, the process of constructing quantitative analysis models for energy storage demand of microgrid users and microgrid group users is as follows:

[0122] To quantify the energy storage demand of microgrid users with the goal of optimizing power supply reliability, this paper identifies the source-load imbalance intervals in the operation of microgrid users and quantifies their key characteristics, including at least area and peak value. It then constructs a demand energy storage capacity model and a demand energy storage power value model with the goal of optimizing power supply reliability, and derives the lower limit of the demand energy storage capacity and demand energy storage power value to ensure that microgrid users do not experience power outages during emergency support phases.

[0123] To ensure optimal power supply reliability for microgrid users, the maximum discharge power of energy storage for a single microgrid user must be greater than the instantaneous power deficit for that user.

[0124] The energy storage capacity required by a single microgrid user is greater than the maximum value of the rolling integral of the power within the reliable power supply pressure range for each time period.

[0125] Specifically, due to factors such as transmission line faults, when a microgrid needs to disconnect from the distribution network and enter islanded operation, the micro gas turbines within the microgrid experience startup delays. Therefore, during the period from the "grid-to-island transition" to the "time when the gas turbines have sufficient power support capacity," emergency power support must be provided by the energy storage of the microgrid users. This paper defines the duration of this process as... Considering that under the shared investment model, it cannot be guaranteed that the shared energy storage configured in the microgrid cluster can provide power support when any microgrid user enters islanded operation, this step only focuses on the independent investment model and establishes a quantitative analysis model of energy storage demand for a single microgrid user with the goal of optimal power supply reliability.

[0126] Figure 2 The height of the reliable power supply pressure range in each time period corresponds to the power deficit that a single microgrid user may experience when operating off-grid, i.e., the power demand value of the microgrid user's energy storage. The maximum discharge power of the microgrid user's energy storage must be greater than the instantaneous power deficit of the microgrid user. Based on this, Using a time window as a reference, the power within the reliable power supply pressure range of each time period is integrally rolled. The area obtained from the integral corresponds to the energy storage capacity configuration requirement of microgrid users, meaning the energy storage capacity must be greater than the maximum value of the integral area. Based on the above approach, a quantitative analysis of the lower limit of the required energy storage capacity and required energy storage power for microgrid users, with the goal of optimal power supply reliability, is conducted:

[0127] The quantitative analysis model for microgrid user power demand with the goal of optimizing power supply reliability is as follows:

[0128] ;

[0129] In the above formula, This represents the required discharge power of energy storage for a single microgrid user with the goal of optimal power supply reliability. The scaling factor is used to characterize... The ratio between the rate of change of load power on a time scale and the rate of change of load power on an hourly time scale; The time set representing the period of reliable power supply pressure in a microgrid, such as Figure 2 As shown.

[0130] Regarding energy storage capacity, unlike the aforementioned energy storage capacity configuration based on the demand for renewable energy consumption, due to... Because the time frame is relatively short, the configuration is not affected by the time-series characteristics between multiple typical days; that is, there is no need to distinguish between intra-day and annual time-scale demands. Under these circumstances, a quantitative analysis model for the microgrid user energy storage capacity demand, with the goal of optimizing power supply reliability, is constructed as follows:

[0131] ;

[0132] In the above formula, This represents the energy storage capacity required by microgrid users with the goal of optimal power supply reliability. This represents the SOC capacity of the microgrid user's energy storage at time t on the d-th typical day.

[0133] Based on the above analysis, the lower limits of the required energy storage capacity and required energy storage power for a single microgrid user, with the goal of optimal power supply reliability, can be derived as follows:

[0134] .

[0135] Step S6: Compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations to obtain the first comprehensive energy storage demand value of microgrid users under the corresponding target combinations; compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection to obtain the second comprehensive energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

[0136] Specifically, this refers to the independent investment model adopted by microgrid users:

[0137] When a microgrid user aims to achieve both optimal economic efficiency and environmental friendliness, the first comprehensive energy storage demand, which combines these two core objectives, is:

[0138] ;

[0139] In the formula, This is the critical value for the primary energy storage power required when a single microgrid user wants to meet the two core objectives of optimal economy and optimal environmental protection. This is the critical value of the primary energy storage capacity required when a microgrid user wants to meet the two core objectives of optimal economy and optimal environmental protection.

[0140] When a microgrid user aims to achieve both optimal economic efficiency and optimal power supply reliability, the first comprehensive energy storage requirement, which combines these two core objectives, is:

[0141] ;

[0142] In the formula, This is the critical value for the primary energy storage capacity required by a single microgrid user when they want to meet the two core objectives of optimal economy and optimal power supply reliability. This is the critical value of the primary energy storage capacity required when a single microgrid user wants to meet the two core objectives of optimal economy and optimal power supply reliability.

[0143] When a microgrid user aims to meet the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, the first comprehensive energy storage requirement, which couples these three needs, is:

[0144] ;

[0145] In the formula, This is the critical value of the primary energy storage capacity required by single microgrid users when they want to meet the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability.

[0146] A system for quantifying and analyzing the energy storage demand of microgrid users, used to implement the above method steps, includes:

[0147] The data acquisition and input unit is used to acquire multiple typical days representing different operating characteristics of each microgrid in the microgrid group.

[0148] The source-load matching analysis unit is connected in communication with the data acquisition and input unit to obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, the difference between the load demand and the output of new energy sources for each microgrid at each time is obtained.

[0149] The pressure zone identification unit communicates with the source-load matching analysis unit and is used to identify the new energy absorption pressure zone and reliable power supply pressure zone of the microgrid based on the difference between the load demand and the new energy output at each time.

[0150] The energy storage complementary window interval identification unit is connected in communication with the source-load matching analysis unit. It is used to overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy absorption pressure and reliable power supply pressure between two microgrids, and to identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group.

[0151] The energy storage demand quantification unit is communicatively connected to the pressure range identification unit and the energy storage complementarity window range identification unit. The energy storage demand quantification unit is used to construct energy storage demand quantification analysis models for microgrid users and microgrid group users based on the new energy consumption pressure range, reliable power supply pressure range, and energy storage complementarity window range shared by microgrid group users. With the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, the energy storage demand quantification analysis model for microgrid users and microgrid group users is constructed respectively, thereby obtaining the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid group users under the corresponding objectives.

[0152] Specifically, the quantitative analysis model for microgrid user energy storage demand includes a quantitative analysis model for microgrid user energy storage capacity demand and a quantitative analysis model for microgrid user power demand.

[0153] The quantitative analysis model for energy storage demand of microgrid users includes a quantitative analysis model for energy storage capacity demand of microgrid users and a quantitative analysis model for power demand of microgrid users.

[0154] The integrated demand quantification unit, which communicates with the energy storage demand quantification unit, is used to compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations, so as to obtain the first integrated energy storage demand value of microgrid users under the corresponding target combinations; and to compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection, so as to obtain the second integrated energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

[0155] Regarding the specific structure of this invention, it should be noted that the connection relationships between the various component modules used in this invention are definite and achievable. Except as specifically described in the embodiments, their specific connection relationships can bring about corresponding technical effects and solve the technical problems proposed by this invention without relying on the execution of corresponding software programs. The models of the components, modules, and specific components appearing in this invention, the connection methods between them, and the conventional usage methods and expected technical effects brought about by the above technical features, unless specifically described, are all publicly disclosed content in patents, journal articles, technical manuals, technical dictionaries, and textbooks that can be obtained by those skilled in the art before the application date, or belong to conventional technology, common knowledge, and other existing technologies in this field. There is no need to elaborate, which makes the technical solution provided in this case clear, complete, and achievable, and can reproduce or obtain corresponding physical products based on this technical means.

[0156] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for quantitative analysis of energy storage demand of microgrid users, characterized in that, Includes the following steps: Step S1: Obtain multiple typical days representing different operating characteristics of each microgrid in the microgrid group; Step S2: Obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, obtain the difference between the load demand and the output of new energy sources for each microgrid at each time. Step S3: Identify the new energy absorption pressure range and reliable power supply pressure range of the microgrid based on the difference between load demand and new energy output at each time. Step S4: Overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy absorption pressure and reliable power supply pressure between pairs of microgrids, and identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group. Step S5: Based on the pressure range of new energy consumption, the pressure range of reliable power supply, and the energy storage complementarity window range for sharing and utilization by microgrid users, with the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, we construct quantitative analysis models of energy storage demand for microgrid users and energy storage demand for microgrid users respectively, so as to obtain the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid users under the corresponding objectives. Step S6: Compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations to obtain the first comprehensive energy storage demand value of microgrid users under the corresponding target combinations; compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection to obtain the second comprehensive energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

2. The method for quantitative analysis of energy storage demand of microgrid users according to claim 1, characterized in that, The quantitative analysis model for microgrid user energy storage demand includes a quantitative analysis model for microgrid user energy storage capacity demand and a quantitative analysis model for microgrid user power demand. The quantitative analysis model for energy storage demand of microgrid users includes a quantitative analysis model for energy storage capacity demand of microgrid users and a quantitative analysis model for power demand of microgrid users.

3. The method for quantitative analysis of energy storage demand of microgrid users according to claim 2, characterized in that, In step S5, with optimal economic efficiency as the core objective, the process of constructing a quantitative analysis model for the energy storage demand of microgrid users and a quantitative analysis model for the energy storage demand of microgrid cluster users is as follows: Based on the constraint of maximizing peak-valley arbitrage profits for single microgrids and microgrid clusters, and combined with the analysis results of the upper limit of charging power during valley hours and the upper limit of discharging power during peak hours, we construct quantitative analysis models of energy storage demand for microgrid users and microgrid cluster users with the goal of economic optimization, respectively. We obtain the energy storage capacity and energy storage power demand of microgrid users with the goal of economic optimization, as well as the energy storage capacity and energy storage power demand of microgrid cluster users with the goal of economic optimization.

4. The method for quantitative analysis of energy storage demand of microgrid users according to claim 2, characterized in that, In step S5, with optimal environmental performance as the core objective, the process of constructing a quantitative analysis model for the energy storage demand of microgrid users and a quantitative analysis model for the energy storage demand of microgrid cluster users is as follows: Based on the constraint relationship between the local consumption rate of new energy and the required energy storage capacity, we construct quantitative analysis models for energy storage demand of microgrid users with the goal of optimal environmental protection and microgrid group users with the goal of optimal environmental protection, respectively. We obtain the required energy storage capacity and required energy storage power of microgrid users with the goal of optimal environmental protection, as well as the required energy storage capacity and required energy storage power of microgrid group users with the goal of optimal environmental protection.

5. The method for quantitative analysis of energy storage demand of microgrid users according to claim 2, characterized in that, In step S5, with optimal power supply reliability as the core objective, the process of constructing a quantitative analysis model of energy storage demand for microgrid users and a quantitative analysis model of energy storage demand for microgrid cluster users is as follows: By identifying the source-load imbalance intervals in the operation of microgrid users and quantifying their key characteristics, including at least area and peak value, a demand-energy storage capacity model and a demand-energy storage power value model with the goal of optimal power supply reliability are constructed. The lower limits of the demand-energy storage capacity and demand-energy storage power value are then derived to ensure that microgrid users do not experience power outages during emergency support phases.

6. The method for quantitative analysis of energy storage demand of microgrid users according to claim 3, characterized in that, In step S5, the constraint on maximizing peak-valley arbitrage profits of the microgrid is expressed in terms of demand storage capacity as follows: During off-peak electricity pricing periods, microgrid users should charge their energy storage devices as much as possible, but the charging power should be less than the sum of the microgrid's transmission channel power and the microgrid's renewable energy redundancy power. During peak electricity price periods, microgrid users should discharge as much as possible, but to avoid power flow back, the discharge power of the microgrid should be less than the net load power of the microgrid. At the same time, ensure that the total charging and discharging power of a single microgrid remains constant throughout the day, so as to guarantee the balance of the final state of energy storage for microgrid users; The constraint on maximizing peak-valley arbitrage profits in microgrids is expressed in terms of demand storage power as follows: The maximum charging rate of energy storage for microgrid users should be greater than the sum of the maximum line transmission power and the surplus power of new energy sources during off-peak electricity price periods, and the maximum discharging power of energy storage for microgrid users should be greater than the maximum net load power during peak electricity price periods, so as to ensure that the charging and discharging rate of energy storage for microgrid users does not lead to a waste of its capacity. The constraint on maximizing peak-valley arbitrage profits in microgrid clusters is manifested in terms of demand storage capacity as follows: On the user side of a microgrid cluster, the energy storage discharge power must not exceed the sum of the net loads of each microgrid.

7. The method for quantitative analysis of energy storage demand of microgrid users according to claim 4, characterized in that, The constraint relationship between the local consumption rate of new energy and the demand for energy storage capacity is as follows: On a daily timescale, the maximum charging power of energy storage for microgrid users should be greater than the maximum excess power of photovoltaic power; the energy storage capacity required by microgrid users should not be less than the preset value of daily absorption rate. On an annual timescale, the pressure range of renewable energy consumption on typical days is comprehensively considered to ensure that the energy storage capacity required by microgrid users can meet the requirement that the renewable energy consumption rate is not lower than the minimum annual consumption rate limit on an annual timescale.

8. The method for quantitative analysis of energy storage demand of microgrid users according to claim 5, characterized in that, For optimal power supply reliability, the maximum discharge power of energy storage for a single microgrid user must be greater than the instantaneous power deficit of the single microgrid user. The energy storage capacity required by a single microgrid user is greater than the maximum value of the rolling integral of the power within the reliable power supply pressure range for each time period.

9. The method for quantitative analysis of energy storage demand of microgrid users according to claim 1, characterized in that, The pressure range for renewable energy absorption is the range where renewable energy output exceeds load demand, while the pressure range for reliable power supply is the range where load demand exceeds available power supply capacity.

10. A system for quantitatively analyzing the energy storage demand of microgrid users, characterized in that, To implement the steps of the method as described in any one of claims 1-9, the method includes: The data acquisition and input unit is used to acquire multiple typical days representing different operating characteristics of each microgrid in the microgrid group; The source-load matching analysis unit is connected to the data acquisition and input unit to obtain the net load power curve of each microgrid on each typical day. Based on the net load power curve, the difference between the load demand and the output of new energy sources for each microgrid at each moment is obtained. The pressure zone identification unit is connected in communication with the source-load matching analysis unit. It is used to identify the new energy consumption pressure zone and the reliable power supply pressure zone of the microgrid based on the difference between the load demand and the new energy output at each time. The energy storage complementary window interval identification unit is connected in communication with the source-load matching analysis unit. It is used to overlay the net load power curves of each microgrid on each typical day to analyze the time misalignment characteristics of the new energy consumption pressure and reliable power supply pressure between two microgrids and identify the energy storage complementary window interval that can be shared and utilized by users of the microgrid group. The energy storage demand quantification unit is communicatively connected to the pressure range identification unit and the energy storage complementarity window range identification unit. The energy storage demand quantification unit is used to construct energy storage demand quantification analysis models for microgrid users and microgrid group users based on the new energy consumption pressure range, reliable power supply pressure range, and energy storage complementarity window range shared by microgrid group users. With the three core objectives of optimal economy, optimal environmental protection, and optimal power supply reliability, the energy storage demand quantification analysis model for microgrid users and microgrid group users is constructed respectively, thereby obtaining the energy storage capacity and energy storage power demand values ​​of microgrid users and microgrid group users under the corresponding objectives. The integrated demand quantification unit, which communicates with the energy storage demand quantification unit, is used to compare and analyze the critical values ​​of the first demand energy storage capacity and the first demand energy storage power obtained by microgrid users under different target combinations, so as to obtain the first integrated energy storage demand value of microgrid users under the corresponding target combinations; and to compare and analyze the critical values ​​of the second demand energy storage capacity and the second demand energy storage power obtained by microgrid group users under the two target combinations of optimal economy and optimal environmental protection, so as to obtain the second integrated energy storage demand value of microgrid group users under the two target combinations of optimal economy and optimal environmental protection.

Images