Microgrid energy storage cost income accounting method and system

Abstract

The invention relates to the technical field of electricity market models, and provides a micro-grid energy storage cost income accounting method and system. The method comprises the following steps: acquiring historical daily operation data of a wind-solar storage power supply and a load in a micro-grid, and data of power purchase and power transmission from a main network by the micro-grid; selecting an adaptive first constraint model or second constraint model according to the self-supply degree of the micro-grid power supply to calculate a cost coefficient and an income coefficient of energy storage and green power allocation; and solving the first constraint model or the second constraint model to obtain a cost coefficient and an income coefficient in the current micro-grid, and optimizing daily charging cost and daily income of energy storage in the current micro-grid. According to the method, the adaptive constraint model is dynamically selected in combination with the self-sufficient degree of the micro-grid power supply, so that the cost coefficient and the income coefficient conforming to the energy storage condition of the current micro-grid are obtained, the daily charging cost and the daily income of the energy storage in the current micro-grid are further calculated, and a high-precision energy storage cost income accounting result is obtained.

Description

Technical Field

[0001] The present invention relates to the technical field of power market models, and more specifically, to a microgrid energy storage cost-benefit accounting method and system. Background Art

[0002] Energy storage cost and benefit accounting is the core of the economic evaluation of microgrid energy storage systems. Through accurate accounting, it can provide investors with a clear cost-benefit analysis, reduce investment risks, and enhance the attractiveness of energy storage projects. In a microgrid environment, the value of the energy storage system is not only reflected in direct economic benefits, but also in the enhancement of grid stability and renewable energy absorption capacity. Therefore, developing an accounting method that can comprehensively consider the power self-sufficiency and the multiple values ​​of energy storage systems in microgrids is of great significance to promoting the development of microgrid energy storage technology, achieving energy transformation and sustainable development.

[0003] At present, traditional energy storage cost accounting is mainly based on the construction and operation of energy storage, and is calculated according to the concept of the entire life cycle, while the benefits are calculated according to the peak-valley difference, selling at peak and buying at valley, but the electricity price is calculated according to the cost of purchasing electricity and the price of electricity sales, ignoring the cost and benefits of green electricity generation in the microgrid. At the same time, some traditional benefit accounting methods assume that energy storage does not require electricity purchase costs, and assume that the power self-sufficiency of the microgrid is 100%. This will result in the cost and benefit accounting results of energy storage still attributing all the costs of purchasing electricity and the benefits of selling electricity to the energy storage system when the power self-sufficiency of the microgrid is insufficient, making it difficult to accurately measure the economic efficiency of the energy storage system. Summary of the invention

[0004] In order to overcome the defect of the above-mentioned prior art that it is difficult to accurately measure the economic efficiency of the energy storage system, the present invention provides a microgrid energy storage cost-benefit accounting method and system.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] A method for calculating the cost and benefit of microgrid energy storage comprises the following steps:

[0007] Obtain the historical daily operation data of wind, solar and storage power sources and loads in the microgrid, as well as the data on power purchase and power transmission from the microgrid to the main grid;

[0008] Selecting an adapted first constraint model or a second constraint model according to the self-sufficiency of the microgrid power supply to calculate the cost coefficient and the benefit coefficient of energy storage and green electricity sharing;

[0009] After solving the first constraint model or the second constraint model, the cost coefficient and the benefit coefficient in the current microgrid are obtained, and the daily charging cost and daily benefit of the energy storage in the current microgrid are optimized.

[0010] Furthermore, the present invention also proposes a microgrid energy storage cost-benefit accounting system, comprising:

[0011] The data acquisition module is used to obtain the historical daily operation data of wind, solar and energy storage sources and loads in the microgrid, as well as the data on the microgrid's purchase and transmission of electricity to the main grid;

[0012] A power self-sufficiency calculation module is used to calculate the current power self-sufficiency of the microgrid;

[0013] A coefficient calculation module, on which a first constraint model and a second constraint model are mounted, for calling the first constraint model or the second constraint model according to the current microgrid power self-sufficiency to calculate the cost coefficient and benefit coefficient of energy storage and green electricity sharing;

[0014] The cost-benefit calculation module is used to optimize the calculation of the daily charging cost and daily income of the energy storage in the current microgrid based on the cost coefficient and income coefficient shared by the current energy storage and green electricity.

[0015] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0016] The present invention combines the microgrid power self-sufficiency to dynamically select an adaptive constraint model to obtain a cost coefficient and a benefit coefficient that conform to the current microgrid energy storage situation, which is further used to calculate the daily charging cost and daily benefit of the energy storage in the current microgrid, and obtain a high-precision energy storage cost-benefit accounting result. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 The present invention is a flowchart of a method for calculating the cost and benefit of microgrid energy storage according to an embodiment of the present invention.

[0018] Figure 2 The present invention is a general flow chart of a method for calculating the cost and benefit of microgrid energy storage according to one embodiment of the present invention.

[0019] Figure 3 The present invention is a schematic diagram of a microgrid energy storage cost-benefit calculation system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0020] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present invention. Instead, they are merely examples of devices and methods consistent with some aspects of the present invention as detailed in the appended claims.

[0021] The terms used in the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention. The singular forms "a", "the" and "the" used in the present invention and the appended claims are also intended to include plural forms unless the context clearly indicates other meanings. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0022] It should be understood that although the terms first, second, third, etc. may be used in the present invention to describe various information, these information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present invention, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0023] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] Example 1

[0025] This embodiment proposes a microgrid energy storage cost-benefit calculation method, such as Figure 1 , which is a flow chart of the microgrid energy storage cost-benefit calculation method of this embodiment.

[0026] The microgrid energy storage cost-benefit calculation method proposed in this embodiment includes the following steps:

[0027] Obtain the historical daily operation data of wind, solar and storage power sources and loads in the microgrid, as well as the data on power purchase and power transmission from the microgrid to the main grid;

[0028] Selecting an adapted first constraint model or a second constraint model according to the self-sufficiency of the microgrid power supply to calculate the cost coefficient and the benefit coefficient of energy storage and green electricity sharing;

[0029] After solving the first constraint model or the second constraint model, the cost coefficient and the benefit coefficient in the current microgrid are obtained, and the daily charging cost and daily benefit of the energy storage in the current microgrid are optimized.

[0030] This embodiment dynamically adjusts the cost-benefit coefficient in combination with the power self-sufficiency of the microgrid to optimize the calculation results of the daily charging cost and daily income of the energy storage in the microgrid, thereby ensuring the accuracy of the energy storage cost-benefit results.

[0031] In an optional embodiment, the collected data includes historical daily operation data of wind power, photovoltaic power and load in the microgrid, specifically, wind power operation output data P wind，t , Photovoltaic operation output data P PV，t , load power Lall，t ; Historical daily operation charging and discharging data of energy storage in the microgrid, specifically, including energy storage charging power and discharge power And, the electricity price of the microgrid when it purchases electricity from the main grid is buy，t , electricity price ρ sell，t , the power P injected into the microgrid by the main grid gird_buy，t and the electric power P sent back from the microgrid to the main grid gird_sell，t .

[0032] Exemplarily, in this embodiment, data collection is performed at a sampling interval of 15 minutes, that is, 96 sampling moments are set in one day, t=1, 2, . . . , 96.

[0033] In an optional embodiment, the microgrid power self-sufficiency includes the ratio of wind, solar, and storage power generation to load power consumption in the microgrid at time t; its expression is:

[0034]

[0035] Among them, K t represents the power self-sufficiency of the microgrid at time t; when K t When K ≥1, it means that the power generation of the power supply in the microgrid meets the power demand of the load; when K t When P < 1, it means that the power generation of the power supply in the microgrid cannot meet the power demand of the load; PV，t , P wind，t Represents the photovoltaic and wind power operating output data at time t; Indicates the energy storage discharge power at time t; L all，t It represents the electrical power consumed by the load at time t.

[0036] Further, in an optional embodiment, selecting the first constraint model or the second constraint model to be adapted according to the power self-sufficiency of the microgrid includes:

[0037] According to the power self-sufficiency K of the microgrid at time t t Is it greater than or equal to 1 to set the first constraint model and the second constraint model; wherein:

[0038] When K t When ≥1, the first constraint model is selected, which considers that the cost is borne by the energy storage and the benefits are evenly shared between the energy storage and the green electricity. The first constraint model is set considering the charging and discharging state of the energy storage, and its expression is:

[0039]

[0040] When K tWhen <1, the second constraint model is selected, which considers the cost sharing between energy storage and load, and the profit is determined by the power purchase price; its expression is:

[0041]

[0042] Among them, U t is the cost coefficient of energy storage and green electricity sharing at time t; W t is the profit coefficient of energy storage and green electricity sharing at time t; ρ sell，t , buy，t They are the electricity selling price and electricity purchasing price of the microgrid from the main grid at time t respectively; represents the energy storage charging power at time t; P gird_buy，t represents the electric power injected into the microgrid by the main grid at time t; P gird_sell，t It represents the electric power fed back from the microgrid to the main grid at time t.

[0043] In addition, in the first constraint model and the second constraint model of this embodiment, the charging power is not considered. When it is 0, for In the case of energy storage, there is no charging demand, so there is no cost sharing task. In this embodiment, it is optional to When the cost factor is set to U t =0.

[0044] For example, Figure 2 As shown, it is the overall flow chart of the microgrid energy storage cost-benefit accounting method of this embodiment.

[0045] It should be noted that the cost coefficient refers to the price coefficient of the energy storage unit charging cost formed by reasonably allocating the electricity purchase cost based on the current situation of the microgrid purchasing electricity from the main grid; the profit coefficient refers to the price coefficient of the energy storage unit electricity sales revenue formed by reasonably allocating the electricity sales revenue based on the current situation of the microgrid selling electricity to the load and the upper-level power grid.

[0046] In this embodiment, the first constraint model corresponds to the self-sufficiency K t The case of ≥1 indicates that the power generation of distributed power sources and energy storage is greater than the power demand of the load, that is, the power demand of the load can be met within the microgrid and no additional power purchase is required.

[0047] In this regard, for the cost coefficient, when there is still external power purchase at this moment, that is, the power purchase cost is incurred, it means that the energy storage in the microgrid is in a charging state, and the energy storage is presented to the outside as a load. Therefore, in the first constraint model, the power purchase cost is set to be borne by the energy storage. For the profit coefficient, when the energy storage is in a discharging state at this moment, the energy storage and green electricity share the system's profits in the first constraint model.

[0048] Among them, the cost coefficient also takes into account the self-sufficiency K t ≥1, the profit that green electricity in the microgrid should have obtained, that is, In addition, the electric power injected from the main grid into the microgrid may be greater than the energy storage charging power, that is, there may be grid loss electricity. Therefore, the calculation of grid loss electricity is also considered in the first constraint model of this embodiment.

[0049] In this embodiment, the second constraint model corresponds to the self-sufficiency K t When the value is less than 1, it means that the power generation of the microgrid cannot meet the power demand of the load at the current moment, and additional power needs to be purchased.

[0050] In this regard, for the cost coefficient, when the energy storage is in a charging state at this moment, the electricity purchased from outside may be for load power consumption or for energy storage charging. Therefore, in the second model, the energy storage and the load share the system cost. For the profit coefficient, considering that the power generation of the power supply in the microgrid cannot meet the power demand of the load at the current moment, only the discharge of the energy storage itself is considered, and the price of the purchased electricity is used instead of the price of the online electricity to calculate the discharge profit.

[0051] The amount of electricity purchased by the microgrid from the outside may be equal to the amount of electricity required to charge the energy storage and the self-sufficiency K. t <1, but the electricity purchased by the microgrid from the outside may also include some network loss electricity, etc. Therefore, the calculation of network loss electricity is considered in the second constraint model of this embodiment.

[0052] For example, without considering the power loss of the grid, the cost coefficient U in the second constraint model is t =ρ buy，t .

[0053] In addition, in the calculation process of the profit coefficient in this embodiment, the situation that the energy storage is in a charging state is not considered. When the energy storage is in a charging state, no profit is generated. When the profit coefficient is set to W t =0.

[0054] Further, in an optional embodiment, after solving the first constraint model or the second constraint model, the cost coefficient and the benefit coefficient in the current microgrid are obtained, and the daily charging cost and the daily benefit of the energy storage in the current microgrid are optimized, including:

[0055] According to the power self-sufficiency K of the microgrid at the current moment t Select the first constraint model or the second constraint model and solve it to obtain the cost coefficient U in the current microgrid. t and the profit coefficient W t ;

[0056] According to the current charging and discharging power of energy storage, the daily charging cost and daily income of energy storage in the current microgrid are optimized; its expression is:

[0057]

[0058]

[0059] Among them, U is the daily charging cost of microgrid energy storage, and W is the daily income of microgrid energy storage.

[0060] In this embodiment, according to the power self-sufficiency K of the microgrid at time t t Whether it is greater than or equal to 1, the adaptive constraint model is dynamically selected to solve the cost coefficient and benefit coefficient that meet the current microgrid energy storage situation, which are further used to calculate the daily charging cost and daily income of the energy storage in the current microgrid, and obtain a high-precision energy storage cost-benefit accounting result.

[0061] Example 2

[0062] This embodiment applies the microgrid energy storage cost-benefit calculation method proposed in Embodiment 1, and proposes a microgrid energy storage cost-benefit calculation system, such as Figure 3 , which is an architecture diagram of the microgrid energy storage cost-benefit accounting system of this embodiment.

[0063] The microgrid energy storage cost-benefit calculation system proposed in this embodiment includes:

[0064] The data acquisition module is used to obtain the historical daily operation data of wind, solar and energy storage sources and loads in the microgrid, as well as the data on the microgrid's purchase and transmission of electricity to the main grid;

[0065] A power self-sufficiency calculation module is used to calculate the current power self-sufficiency of the microgrid;

[0066] A coefficient calculation module, on which a first constraint model and a second constraint model are mounted, for calling the first constraint model or the second constraint model according to the current microgrid power self-sufficiency to calculate the cost coefficient and benefit coefficient of energy storage and green electricity sharing;

[0067] The cost-benefit calculation module is used to optimize the calculation of the daily charging cost and daily income of the energy storage in the current microgrid based on the cost coefficient and income coefficient shared by the current energy storage and green electricity.

[0068] In an optional embodiment, in the data collection module, the collected historical daily operation data includes wind power operation output data P wind，t , Photovoltaic operation output data P PV，t , load power L all，t , Energy storage charging power and discharge power The collected data on power purchase and transmission from the microgrid to the main grid include the power purchase price ρ of the microgrid to the main grid buy，t , electricity price ρ sell，t , and the electric power P injected into the microgrid by the main grid gird_buy，t and the electric power P sent back from the microgrid to the main grid gird_sell，t .

[0069] In an optional embodiment, in the power self-sufficiency calculation module, the microgrid power self-sufficiency includes the ratio of wind, solar, and storage power generation power to load power consumption in the microgrid at time t; its expression is:

[0070]

[0071] Among them, K t represents the power self-sufficiency of the microgrid at time t; when K t When K ≥1, it means that the power generation of the power supply in the microgrid meets the power demand of the load; when K t When P < 1, it means that the power generation of the power supply in the microgrid cannot meet the power demand of the load; PV，t , P wind，t Represents the photovoltaic and wind power operating output data at time t; Indicates the energy storage discharge power at time t; L all，t It represents the electrical power consumed by the load at time t.

[0072] In an optional embodiment, in the coefficient calculation module, according to the power self-sufficiency K of the microgrid at time t t Whether it is greater than or equal to 1, the first constraint model and the second constraint model are selected; wherein:

[0073] When K t When ≥1, the first constraint model is selected, which considers that the cost is borne by the energy storage and the benefits are evenly shared between the energy storage and the green electricity. The first constraint model is set considering the charging and discharging state of the energy storage, and its expression is:

[0074]

[0075] When K t When <1, the second constraint model is selected, which considers the cost sharing between energy storage and load, and the profit is determined by the power purchase price; its expression is:

[0076]

[0077] Among them, U t is the cost coefficient of energy storage and green electricity sharing at time t; W t is the profit coefficient of energy storage and green electricity sharing at time t; ρ sell，t , buy，tThey are the electricity selling price and electricity purchasing price of the microgrid from the main grid at time t respectively; represents the energy storage charging power at time t; P gird_buy，t represents the electric power injected into the microgrid by the main grid at time t; P gird_sell，t It represents the electric power fed back from the microgrid to the main grid at time t.

[0078] In an optional embodiment, in the cost-benefit calculation module, when calculating the daily charging cost and daily income of the energy storage in the current microgrid, the daily charging cost and daily income of the energy storage in the current microgrid are optimized according to the charging and discharging power of the current energy storage; the expression is:

[0079]

[0080]

[0081] Among them, U is the daily charging cost of microgrid energy storage, and W is the daily income of microgrid energy storage.

[0082] It can be understood that the system of this embodiment corresponds to the method of the above-mentioned embodiment 1, and the options in the above-mentioned embodiment 1 are also applicable to this embodiment, so they will not be described repeatedly here.

[0083] Example 3

[0084] This embodiment proposes a computer device, including a memory and a processor, wherein the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the processor executes all or part of the steps of the microgrid energy storage cost-benefit accounting method proposed in Example 1.

[0085] Example 4

[0086] This embodiment proposes a storage medium having computer-readable instructions stored thereon, wherein the computer-readable instructions, when executed by a processor, implement all or part of the steps of the microgrid energy storage cost-benefit accounting method proposed in Embodiment 1.

[0087] Exemplarily, the storage medium includes, but is not limited to, a USB flash drive, a mobile hard disk, a read-only memory (ROM), a random access memory (RAM), a magnetic disk or an optical disk, and other media that can store program codes.

[0088] Exemplarily, the instructions, programs, code sets or instruction sets may be implemented using conventional programming languages.

[0089] Exemplarily, the processor includes but is not limited to a smart phone, a personal computer, a server, a network device, etc., and is used to execute all or part of the steps of the microgrid energy storage cost-benefit accounting method described in Example 1.

[0090] Each embodiment of the present invention is described in a progressive manner, and the same or similar parts between the embodiments can be referred to each other, and each embodiment focuses on the differences from other embodiments. In particular, for the device embodiment, since it is basically similar to the method embodiment, the description is relatively simple, and the relevant parts can be referred to the partial description of the method embodiment. The device embodiment described above is merely exemplary, in which the modules described as separate components may or may not be physically separated, and the functions of each module can be implemented in the same or one or more software and / or hardware when implementing the scheme of the present invention. It is also possible to select some or all of the modules according to actual needs to achieve the purpose of the scheme of this embodiment.

[0091] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. A method for calculating the cost and benefit of microgrid energy storage, characterized in that: The following steps are involved: Obtain the historical daily operation data of wind, solar and storage power sources and loads in the microgrid, as well as the data on power purchase and power transmission from the microgrid to the main grid; Selecting an adapted first constraint model or a second constraint model according to the self-sufficiency of the microgrid power supply to calculate the cost coefficient and the benefit coefficient of energy storage and green electricity sharing; After solving the first constraint model or the second constraint model, the cost coefficient and the benefit coefficient in the current microgrid are obtained, and the daily charging cost and daily benefit of the energy storage in the current microgrid are optimized.

2. The microgrid energy storage cost-benefit calculation method according to claim 1 is characterized in that: The microgrid power self-sufficiency includes the ratio of wind, solar, and storage power generation to load power consumption in the microgrid at time t; its expression is: Among them, K t represents the power self-sufficiency of the microgrid at time t; when K t When K ≥1, it means that the power generation of the power supply in the microgrid meets the power demand of the load; when K t When P < 1, it means that the power generation of the power supply in the microgrid cannot meet the power demand of the load; PV,t , P wind,t Represents the photovoltaic and wind power operating output data at time t; Indicates the energy storage discharge power at time t; L all,y Indicates the electrical power consumed by the load at time t.

3. The microgrid energy storage cost-benefit calculation method according to claim 2 is characterized in that: The method of selecting an adapted first constraint model or a second constraint model according to the microgrid power self-sufficiency degree includes: According to the power self-sufficiency K of the microgrid at time t t Is it greater than or equal to 1 to set the first constraint model and the second constraint model; wherein: When K t When ≥1, the first constraint model is selected, which considers that the cost is borne by the energy storage and the benefits are evenly shared between the energy storage and the green electricity. The first constraint model is set considering the charging and discharging state of the energy storage, and its expression is: When K t <1, the second constraint model is selected, which considers the cost sharing between energy storage and load, and the profit determined by the power purchase price; its expression is: Among them, U t is the cost coefficient of energy storage and green electricity sharing at time t; W t is the profit coefficient of energy storage and green electricity sharing at time t; ρ sell,t , buy,t They are the electricity selling price and electricity purchasing price of the microgrid from the main grid at time t respectively; represents the energy storage charging power at time t; P gird_buy,t represents the electric power injected into the microgrid by the main grid at time t; P gird_sell,t It represents the electric power fed back from the microgrid to the main grid at time t.

4. The microgrid energy storage cost-benefit calculation method according to claim 3 is characterized in that: The step of solving the first constraint model or the second constraint model to obtain the cost coefficient and the benefit coefficient in the current microgrid and optimizing the daily charging cost and the daily benefit of the energy storage in the current microgrid includes: According to the power self-sufficiency K of the microgrid at the current moment t Select the first constraint model or the second constraint model and solve it to obtain the cost coefficient U in the current microgrid. t and the profit coefficient W t ; According to the current charging and discharging power of energy storage, the daily charging cost and daily income of energy storage in the current microgrid are optimized; its expression is: Among them, U is the daily charging cost of microgrid energy storage, and W is the daily income of microgrid energy storage.

5. The microgrid energy storage cost-benefit calculation method according to any one of claims 1 to 4, characterized in that: The historical daily operation data includes wind power operation output data P wind,t , Photovoltaic operation output data P PV,t , load power L all,t , Energy storage charging power and discharge power The data of power purchase and transmission from the microgrid to the main grid includes the power purchase price ρ of the microgrid to the main grid buy,t , electricity price ρ sell,t , and the electric power P injected into the microgrid by the main grid gird_buy,t and the electric power P sent back from the microgrid to the main grid gird_sell,t .

6. A microgrid energy storage cost-benefit accounting system, characterized in that: include: The data acquisition module is used to obtain the historical daily operation data of wind, solar and energy storage sources and loads in the microgrid, as well as the data on the microgrid's purchase and transmission of electricity to the main grid; A power self-sufficiency calculation module is used to calculate the current power self-sufficiency of the microgrid; A coefficient calculation module, on which a first constraint model and a second constraint model are mounted, for calling the first constraint model or the second constraint model according to the current microgrid power self-sufficiency to calculate the cost coefficient and benefit coefficient of energy storage and green electricity sharing; The cost-benefit calculation module is used to optimize the calculation of the daily charging cost and daily income of the energy storage in the current microgrid based on the cost coefficient and income coefficient shared by the current energy storage and green electricity.

7. The microgrid energy storage cost-benefit accounting system according to claim 6, characterized in that: In the power self-sufficiency calculation module, the microgrid power self-sufficiency includes the ratio of wind, solar, and storage power generation to load power consumption in the microgrid at time t; its expression is: Among them, K t represents the power self-sufficiency of the microgrid at time t; when K t When K ≥1, it means that the power generation of the power supply in the microgrid meets the power demand of the load; when K t When P < 1, it means that the power generation of the power supply in the microgrid cannot meet the power demand of the load; PV,t , P wind,t Represents the photovoltaic and wind power operating output data at time t; Indicates the energy storage discharge power at time t; L all,t Indicates the electrical power consumed by the load at time t.

8. The microgrid energy storage cost-benefit accounting system according to claim 7, characterized in that: In the coefficient calculation module, according to the power self-sufficiency K of the microgrid at time t, t whether it is greater than or equal to 1, selecting the first constraint model and the second constraint model; in: When K t When ≥1, the first constraint model is selected, which considers that the cost is borne by the energy storage and the benefits are evenly shared between the energy storage and the green electricity. The first constraint model is set considering the charging and discharging state of the energy storage, and its expression is: When K t <1, the second constraint model is selected, which considers the cost sharing between energy storage and load, and the profit determined by the power purchase price; its expression is: Among them, U t is the cost coefficient of energy storage and green electricity sharing at time t; W t is the profit coefficient of energy storage and green electricity sharing at time t; ρ sell,t , buy,t They are the electricity selling price and electricity purchasing price of the microgrid from the main grid at time t respectively; represents the energy storage charging power at time t; P gird_buy,t represents the electric power injected into the microgrid by the main grid at time t; P gird_sell,t It represents the electric power fed back from the microgrid to the main grid at time t.

9. The microgrid energy storage cost-benefit accounting system according to claim 8, characterized in that: In the cost-benefit calculation module, when calculating the daily charging cost and daily income of the energy storage in the current microgrid, the daily charging cost and daily income of the energy storage in the current microgrid are optimized according to the charging and discharging power of the current energy storage; Its expression is: Among them, U is the daily charging cost of microgrid energy storage, and W is the daily income of microgrid energy storage.

10. The microgrid energy storage cost-benefit calculation system according to any one of claims 6 to 9, characterized in that: In the data collection module, the historical daily operation data collected includes wind power operation output data P wind,t , Photovoltaic operation output data P PV,t , load power L all,t , Energy storage charging power and discharge power The collected data on power purchase and transmission from the microgrid to the main grid include the power purchase price ρ of the microgrid to the main grid buy,t , electricity price ρ sell,t , and the electric power P injected into the microgrid by the main grid gird_buy,t and the electric power P sent back from the microgrid to the main grid gird_sell,t .

Images