Micro-grid new energy storage ratio optimization method and system

Abstract

The invention relates to the technical field of power resource configuration, and provides a microgrid new energy storage ratio optimization method and system. The method comprises the following steps: acquiring a current configuration ratio of wind power to photovoltaic power in a target micro-grid, basic equipment data of the wind power and photovoltaic power in the target micro-grid, and current configuration data of an energy storage device; constructing a micro-grid equivalent investment cost model, updating the micro-grid equivalent investment cost model, and judging a current micro-grid benefit state; the method comprises the steps of establishing a new energy storage ratio optimization function according to a current microgrid benefit state, optimizing the new energy storage ratio optimization function by taking cost minimization as a target under the condition of meeting a preset first constraint condition according to the current microgrid benefit state, obtaining a new energy storage ratio, and configuring the energy storage capacity in a target microgrid based on the new energy storage ratio. According to the method, engineering practicability can be met, it is ensured that the energy storage capacity can meet actual requirements, economic rationality can be kept, and therefore the overall economical efficiency and the operation efficiency of the micro-grid are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of power resource allocation, and more specifically, to a method and system for optimizing the ratio of new energy storage in a microgrid. Background Art

[0002] A microgrid is a small power system that consists of distributed power sources, energy storage devices, loads, monitoring and protection devices, etc. It is a small power supply and utilization system that can achieve basic balance of internal power.

[0003] At present, the configuration of microgrid energy storage capacity mostly relies on empirical rules, such as determining the energy storage ratio based on the installed capacity of the new energy power generation system. Although this method is easy to operate, the ratio is set by experts' experience and it is difficult to accurately adapt to the actual needs of the microgrid in practical applications. The overall optimization method attempts to achieve accurate configuration of energy storage capacity by comprehensively considering multiple factors. This method can provide a more comprehensive solution in theory, but in practical applications, it is often difficult to promote and replicate due to the complex calculation process and high technical requirements. Summary of the invention

[0004] In order to overcome the defects of the microgrid energy storage capacity ratio optimization described in the above-mentioned prior art that it is difficult to accurately adapt to the actual needs of the microgrid and the calculation process is complicated, the present invention provides a microgrid new energy storage ratio optimization 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 optimizing the ratio of new energy storage in a microgrid comprises the following steps:

[0007] Collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device;

[0008] Constructing a microgrid equivalent investment cost model, and determining the current microgrid benefit status after updating the microgrid equivalent investment cost model;

[0009] A new energy storage ratio optimization function is constructed. According to the current microgrid benefit status and under the preset first constraint condition, the new energy storage ratio optimization function is optimized with the goal of minimizing cost to obtain the new energy storage ratio, and the energy storage capacity in the target microgrid is configured based on the new energy storage ratio.

[0010] Furthermore, the present invention also proposes a microgrid new energy storage ratio optimization system, which applies the microgrid new energy storage ratio optimization method proposed in the present invention. The system includes:

[0011] The data acquisition module is used to collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device;

[0012] The microgrid benefit evaluation module is equipped with a microgrid equivalent investment cost model, which is used to calculate the equivalent investment cost based on the collected microgrid new energy storage data and evaluate the current microgrid benefit status;

[0013] A new energy storage ratio optimization module is used to optimize the new energy storage ratio optimization function according to the current microgrid benefit state and under the preset first constraint condition with the goal of minimizing cost to obtain the new energy storage ratio;

[0014] A configuration module is used to configure the energy storage capacity in the target microgrid based on the new energy storage ratio.

[0015] Furthermore, the present invention also proposes a device, including a memory and a processor, wherein the memory stores computer-readable instructions, wherein when the computer-readable instructions are executed by the processor, the processor executes all or part of the steps of the microgrid new energy storage ratio optimization method as described in the present invention.

[0016] Furthermore, the present invention also 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 new energy storage ratio optimization method as described in the present invention.

[0017] Compared with the prior art, the technical solution of the present invention has the following beneficial effects:

[0018] The present invention performs comprehensive cost calculation based on wind and solar cost parameters, electricity price parameters, etc. in the microgrid, optimizes the ratio of microgrid energy storage capacity while minimizing costs, accurately adapts to the actual needs of the microgrid, simplifies the calculation process, and reduces the cost of computing resources;

[0019] The present invention can meet engineering practicality and ensure that the energy storage capacity can meet actual needs while maintaining economic rationality, thereby improving the overall economy and operation efficiency of the microgrid. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The present invention is a flowchart of a method for optimizing the ratio of new energy storage in a microgrid according to an embodiment of the present invention.

[0021] Figure 2 The present invention is a schematic diagram of a microgrid new energy storage ratio optimization system according to an embodiment of the present invention. DETAILED DESCRIPTION

[0022] 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.

[0023] 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.

[0024] 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".

[0025] The present invention is described in detail below with reference to the accompanying drawings and specific embodiments.

[0026] Example 1

[0027] This embodiment proposes a microgrid new energy storage ratio optimization method, such as Figure 1 , which is a flow chart of the microgrid new energy storage ratio optimization method of this embodiment.

[0028] The microgrid new energy storage ratio optimization method proposed in this embodiment includes the following steps:

[0029] S1. Collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device;

[0030] S2. construct a microgrid equivalent investment cost model, and determine the current microgrid benefit status after updating the microgrid equivalent investment cost model;

[0031] S3, constructing a new energy storage ratio optimization function, according to the current microgrid benefit status, under the preset first constraint condition, optimizing the new energy storage ratio optimization function with the goal of minimizing cost, and obtaining the new energy storage ratio;

[0032] S4. Configure the energy storage capacity in the target microgrid based on the new energy storage ratio.

[0033] In view of the shortcomings of the current configuration of new energy storage, which is highly subjective and lacks rationality due to human experience, and the complex calculation process and high technical requirements of mathematical optimization methods, this embodiment proposes a practical engineering method for configuring new energy storage in microgrids.

[0034] In this embodiment, a comprehensive cost calculation is performed based on wind and solar cost parameters, electricity price parameters, etc. in the microgrid, and the energy storage capacity of the microgrid is optimized while minimizing the cost, so as to accurately adapt to the actual needs of the microgrid, simplify the calculation process, and reduce the cost of computing resources. This embodiment can meet engineering practicality and ensure that the energy storage capacity can meet actual needs while maintaining economic rationality, thereby improving the overall economy and operation efficiency of the microgrid.

[0035] It should be noted that the power sources in the microgrid are mostly distributed power sources with smaller capacity, such as micro gas turbines, fuel cells, photovoltaic cells, small wind turbines, etc. This embodiment optimizes the energy storage ratio of the microgrid composed of distributed power sources using photovoltaic cells and wind turbines, and is also applicable to the energy storage ratio optimization in microgrids containing other types of distributed power sources.

[0036] In an optional embodiment, the microgrid equivalent investment cost model includes a new energy equivalent investment cost model and an energy storage equivalent investment cost model.

[0037] Among them, the new energy equivalent investment cost model is:

[0038]

[0039] Among them, I PV is the unit installed capacity investment cost of photovoltaics, Y_PV is the equipment life of photovoltaics; Irr is the discount rate; I WP is the unit installed capacity investment cost of the wind turbine, Y_WP is the equipment life of the wind turbine; β is the current configuration ratio of wind power and photovoltaic power in the target microgrid.

[0040] The energy storage equivalent investment cost model is:

[0041]

[0042] Among them, I B is the investment cost per unit installed capacity of energy storage, and Y_BS is the equipment life of energy storage.

[0043] In an optional embodiment, after the microgrid equivalent investment cost model is updated, judging the current microgrid benefit status includes the following steps:

[0044] The collected current configuration ratio of wind power and photovoltaic power and its basic equipment data, as well as the current configuration data of the energy storage device are input into the microgrid equivalent investment cost model to update the model and obtain the current new energy equivalent investment cost I of the target microgrid. green and energy storage equivalent investment cost I BS ;

[0045] Based on the maximum economic benefit of the energy storage system in the peak-valley electricity price difference, combined with the energy storage equivalent investment cost I BS Determine the current microgrid benefit status. If the maximum economic benefit of the current energy storage system in the peak-valley electricity price difference is greater than the equivalent investment cost of energy storage, BS , it means that the current microgrid benefit status is beneficial; otherwise, it means that the current microgrid benefit status is ineffective.

[0046] In this embodiment, the equivalent investment cost of new energy and energy storage in the current microgrid is obtained based on the microgrid equivalent investment cost model, and is further compared with the maximum economic benefit of the energy storage system in the peak-valley electricity price difference to evaluate the current benefit status of the microgrid. In the process of optimizing the energy storage ratio, different optimization operations can be performed according to the current benefit status to adapt to the actual needs of the microgrid.

[0047] Further, in an optional embodiment, the maximum economic benefit of the energy storage system in the peak-valley electricity price difference is combined with the energy storage equivalent investment cost I BS Judging the current microgrid benefit status includes the following steps:

[0048] Select the maximum power charging and discharging time parameter H of the energy storage;

[0049] Get the peak-to-valley price difference ρ of the target microgrid grid_updown,d , where d = 1, 2, ..., 365;

[0050] Calculate the maximum economic benefit of energy storage system in the peak-valley electricity price difference and the equivalent investment cost of energy storage I BS The difference; its expression is:

[0051]

[0052] Among them, when K>0, it means that the current microgrid benefit state is beneficial; when K≤0, it means that the current microgrid benefit state is ineffective.

[0053] In this embodiment, the peak-valley electricity price difference is multiplied by the maximum power charging and discharging time of the energy storage, and the maximum economic benefit that the energy storage system can achieve through the peak-valley electricity price difference under ideal conditions can be obtained. This value can assist in determining the capacity ratio of the microgrid energy storage system to achieve optimal cost. Furthermore, by comparing the maximum economic benefit of the energy storage system in the peak-valley electricity price difference with the energy storage equivalent investment cost IBS , the microgrid benefit status evaluation results can be obtained.

[0054] Further, in an optional embodiment, according to the current microgrid benefit state, the new energy storage ratio optimization function is optimized with the goal of minimizing cost to obtain the new energy storage ratio, including the following steps:

[0055] Evaluate the current microgrid benefit status. If the current microgrid benefit status is ineffective, that is, K≤0, no energy storage will be configured.

[0056] If the current microgrid benefit state is effective, that is, K>0, the new energy storage ratio optimization function is optimized with the goal of minimizing the cost; then the expression of the new energy storage ratio optimization function is:

[0057]

[0058] Among them, λ is the ratio of new energy to energy storage; represents the electricity purchase cost of the microgrid from the main grid, ρ grid_buy,d is the electricity price that the microgrid purchases from the main grid on day d, δ green.d represents the predicted output characteristics of renewable energy in the microgrid system on day d, C green Characterize the economic feasibility of power trading between the microgrid and the main grid in different time periods.

[0059] In this embodiment, first consider whether it is profitable to configure energy storage in the current microgrid system. If it is not profitable, no energy storage will be configured. If it is profitable, further evaluate whether it is profitable to configure new energy in the current microgrid system. Based on the profitability of energy storage configuration and new energy configuration, optimize the new energy storage ratio to ensure that the configuration cost of the microgrid is minimized.

[0060] Furthermore, when the configuration of new energy is profitable, the ratio of new energy to energy storage is set to 1, that is, when the configuration of new energy and energy storage is equal, the maximum benefit can be achieved, ensuring that the energy storage system can fully utilize the electricity generated by new energy power generation and improve energy utilization. When the configuration of new energy is not profitable, consider configuring energy storage to make up for the loss.

[0061] In this embodiment, whether the new energy configuration generates profit is determined based on the electricity purchase cost of the microgrid from the main grid. Specifically, the electricity purchase cost of the microgrid from the main grid is the equivalent income that the microgrid can obtain after constructing the new energy.

[0062] Further, in an optional embodiment, the method further includes: setting an optimization function constraint condition, wherein the constraint condition includes that the maximum value of the new energy-energy storage ratio λ is 1; then, the new energy-energy storage ratio optimization function is set to:

[0063]

[0064] In this embodiment, the maximum value of the configured energy storage is set to 1, that is, the installed capacity of the energy storage is not greater than the installed capacity of the new energy. When the installed capacity of the energy storage is much greater than the installed capacity of the new energy, the energy storage system in the microgrid system may not be able to fully utilize the electricity generated by the new energy generation, resulting in reduced energy utilization efficiency. At the same time, the energy storage system needs to be coordinated with the new energy generation, load demand, etc. If the installed capacity of the energy storage is too large, it will increase the complexity of the scheduling and affect the overall operating efficiency of the system.

[0065] In addition, in the microgrid system of this embodiment, energy storage can make profits by utilizing the maximum economic benefit of the peak-valley electricity price difference within the microgrid, which is greater than the equivalent investment cost of energy storage. When the installed capacity of energy storage is much larger than the installed capacity of new energy, it is impossible to determine whether the current microgrid system has the benefit of the peak-valley electricity price difference, and it is impossible to ensure maximum benefit.

[0066] In an optional embodiment, configuring the energy storage capacity in the target microgrid based on the new energy storage ratio includes the following steps:

[0067] Obtain the current microgrid's installed capacity of renewable energy, including wind power and photovoltaic installed capacity;

[0068] The energy storage capacity is configured based on the new energy storage ratio λ; its expression is:

[0069] P BS =λP green =λ(P wind +P PV )

[0070] Among them, P BS is the energy storage capacity in the microgrid, P wind is the installed capacity of wind turbines in the microgrid, P PV Photovoltaic installed capacity.

[0071] This embodiment can meet engineering practicality and ensure that the energy storage capacity can meet actual needs while maintaining economic rationality, thereby improving the overall economy and operating efficiency of the microgrid.

[0072] Example 2

[0073] This embodiment proposes a microgrid new energy storage ratio optimization system, and applies the microgrid new energy storage ratio optimization method proposed in Embodiment 1. Figure 2 , which is an architecture diagram of the microgrid new energy storage ratio optimization system of this embodiment.

[0074] The microgrid new energy storage ratio optimization system proposed in this embodiment includes:

[0075] The data acquisition module is used to collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device;

[0076] The microgrid benefit evaluation module is equipped with a microgrid equivalent investment cost model, which is used to calculate the equivalent investment cost based on the collected microgrid new energy storage data and evaluate the current microgrid benefit status;

[0077] A new energy storage ratio optimization module is used to optimize the new energy storage ratio optimization function according to the current microgrid benefit state and under the preset first constraint condition with the goal of minimizing cost to obtain the new energy storage ratio;

[0078] A configuration module is used to configure the energy storage capacity in the target microgrid based on the new energy storage ratio.

[0079] 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.

[0080] Example 3

[0081] 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 new energy storage ratio optimization method proposed in Example 1.

[0082] Example 4

[0083] 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 new energy storage ratio optimization method proposed in Embodiment 1.

[0084] 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.

[0085] Exemplarily, the instructions, programs, code sets or instruction sets may be implemented using conventional programming languages.

[0086] 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 new energy storage ratio optimization method described in Example 1.

[0087] 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.

[0088] 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 optimizing the ratio of new energy storage in a microgrid, characterized in that: The following steps are involved: Collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device; Constructing a microgrid equivalent investment cost model, and determining the current microgrid benefit status after updating the microgrid equivalent investment cost model; A new energy storage ratio optimization function is constructed, and according to the current microgrid benefit status, the new energy storage ratio optimization function is optimized with the goal of minimizing cost to obtain the new energy storage ratio, and the energy storage capacity in the target microgrid is configured based on the new energy storage ratio.

2. The microgrid new energy storage ratio optimization method according to claim 1 is characterized in that: The microgrid equivalent investment cost model includes a new energy equivalent investment cost model and an energy storage equivalent investment cost model; wherein the new energy equivalent investment cost model is: Among them, I PV is the unit installed capacity investment cost of photovoltaics, Y_PV is the equipment life of photovoltaics; Irr is the discount rate; I WP is the unit installed capacity investment cost of the wind turbine, Y_WP is the equipment life of the wind turbine; β is the current configuration ratio of wind power and photovoltaic power in the target microgrid; The energy storage equivalent investment cost model is: Among them, I B is the investment cost per unit installed capacity of energy storage, and Y_BS is the equipment life of energy storage.

3. The microgrid new energy storage ratio optimization method according to claim 2 is characterized in that: After the microgrid equivalent investment cost model is updated, judging the current microgrid benefit status includes the following steps: The collected current configuration ratio of wind power and photovoltaic power and its basic equipment data, as well as the current configuration data of the energy storage device are input into the microgrid equivalent investment cost model to update the model and obtain the current new energy equivalent investment cost I of the target microgrid. green and energy storage equivalent investment cost I BS ; Based on the maximum economic benefit of the energy storage system in the peak-valley electricity price difference, combined with the energy storage equivalent investment cost I BS Determine the energy storage investment benefit status when energy storage is configured in the current microgrid system. If the maximum economic benefit of the current energy storage system in the peak-valley electricity price difference is greater than the energy storage equivalent investment cost I BS , it means that the energy storage investment benefit status when the energy storage is configured in the current microgrid system is beneficial; otherwise, it means that the energy storage investment benefit status when the energy storage is configured in the current microgrid system is ineffective.

4. The microgrid new energy storage ratio optimization method according to claim 3 is characterized in that: The maximum economic benefit of the energy storage system in the peak-valley electricity price difference, combined with the energy storage equivalent investment cost I BS Judging the current microgrid benefit status includes the following steps: Select the maximum power charging and discharging time parameter H of the energy storage; Get the peak-to-valley price difference ρ of the target microgrid grid_updown，d , where d = 1, 2, ..., 365; Calculate the maximum economic benefit of energy storage system in the peak-valley electricity price difference and the equivalent investment cost of energy storage I BS The difference; its expression is: Among them, when K>0, it means that the current microgrid benefit state is beneficial; when K≤0, it means that the current microgrid benefit state is ineffective.

5. The microgrid new energy storage ratio optimization method according to claim 4 is characterized in that: The method of optimizing the new energy storage ratio optimization function according to the current microgrid benefit state with the goal of minimizing cost to obtain the new energy storage ratio includes the following steps: Evaluate the current microgrid benefit status. If the current microgrid benefit status is ineffective, that is, K≤0, no energy storage will be configured. If the current microgrid benefit state is effective, that is, K>0, the new energy storage ratio optimization function is optimized with the goal of minimizing the cost; then the expression of the new energy storage ratio optimization function is: Among them, λ is the ratio of new energy to energy storage; C green =∑ d ρ grid_buy,d ·δ green.d represents the electricity purchase cost of the microgrid from the main grid, ρ grid_buy，d is the electricity price that the microgrid purchases from the main grid on day d, δ green.d It represents the predicted output characteristics of renewable energy in the microgrid system on the dth day.

6. The microgrid new energy storage ratio optimization method according to claim 5 is characterized in that: The method further comprises: Set the optimization function constraint condition, the constraint condition includes that the maximum value of the new energy-energy storage ratio λ is 1; then, the new energy storage ratio optimization function is set to:

7. The microgrid new energy storage ratio optimization method according to any one of claims 1 to 6, characterized in that: Configuring the energy storage capacity in the target microgrid based on the new energy storage ratio includes the following steps: Obtain the current microgrid's installed capacity of renewable energy, including wind power and photovoltaic installed capacity; The energy storage capacity is configured based on the new energy storage ratio λ; its expression is: P BS =λP green =λ(P wind +P PV ) Among them, P BS is the energy storage capacity in the microgrid, P wind is the installed capacity of wind turbines in the microgrid, P PV Photovoltaic installed capacity.

8. A microgrid new energy storage ratio optimization system, applying the microgrid new energy storage ratio optimization method according to any one of claims 1 to 7, characterized in that: include: The data acquisition module is used to collect the current configuration ratio of wind power and photovoltaic power in the target microgrid and its basic equipment data, as well as the current configuration data of the energy storage device; The microgrid benefit evaluation module is equipped with a microgrid equivalent investment cost model, which is used to calculate the equivalent investment cost based on the collected microgrid new energy storage data and evaluate the current microgrid benefit status; A new energy storage ratio optimization module is used to optimize the new energy storage ratio optimization function according to the current microgrid benefit status with the goal of minimizing cost to obtain the new energy storage ratio; A configuration module is used to configure the energy storage capacity in the target microgrid based on the new energy storage ratio.

9. A device comprising a memory and a processor, wherein the memory stores computer-readable instructions, characterized in that: When the computer-readable instructions are executed by the processor, the processor executes all or part of the steps of the microgrid new energy storage ratio optimization method according to any one of claims 1 to 7.

10. A storage medium having computer-readable instructions stored thereon, wherein: When the computer-readable instructions are executed by the processor, all or part of the steps of the microgrid new energy storage ratio optimization method according to any one of claims 1 to 7 are implemented.

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