Capacity configuration method and system for cooperative grid connection of gravity energy storage and electrochemical energy storage

Abstract

The invention discloses a capacity configuration method and system for cooperative grid connection of gravity energy storage and electrochemical energy storage, and the method comprises the steps: obtaining a power generation signal of a power grid, and carrying out the variational mode decomposition and reconstruction, and obtaining the power generation signals of gravity energy storage and electrochemical energy storage; based on the power generation signal and the power response characteristic of the gravity energy storage, determining a power range output by the gravity energy storage; based on the power generation signals of the gravity energy storage and the electrochemical energy storage and in combination with the power range of the gravity energy storage output, determining the power range of the electrochemical energy storage output; based on the output power ranges of the gravity energy storage and the electrochemical energy storage, the capacity configured by the gravity energy storage and the electrochemical energy storage is given respectively. And capacity configuration of collaborative grid connection of gravity energy storage and electrochemical energy storage can be realized.

Description

Technical Field

[0001] The present invention belongs to the technical field of electric energy storage configuration, and specifically relates to a capacity configuration method and system for coordinated grid connection of gravity energy storage and electrochemical energy storage. Background Art

[0002] The large-scale centralized grid connection of renewable energy power systems such as wind power and photovoltaic power has brought challenges to the safe and stable operation of the power grid system. Since the output of renewable energy power systems is random, intermittent and volatile, the power grid system needs to have rapid adjustment capabilities.

[0003] The large-scale application of energy storage systems is conducive to improving the flexibility, economy and safety of power grid systems. Gravity energy storage systems have the advantages of high safety, clean and environmental protection, flexible site selection, and low comprehensive cost. The existing vertical matrix gravity energy storage system converts the potential energy generated by the lifting of heavy blocks into electrical energy. The mechanical structure of gravity energy storage itself determines that its output power has a fixed climbing rate. Gravity energy storage alone cannot quickly meet the power time requirements of the grid side. It is necessary to design a hybrid energy storage system that connects gravity energy storage and electrochemical energy storage in parallel to better meet the power requirements of the grid side.

[0004] The capacity configuration of hybrid energy storage consisting of gravity energy storage and electrochemical energy storage in parallel is the main factor in the system configuration cost. Based on this, how to design a capacity configuration method and system for vertical matrix gravity energy storage and electrochemical energy storage to achieve the optimal capacity configuration of the hybrid energy storage system consisting of gravity energy storage and electrochemical energy storage is an urgent problem to be solved by technical personnel in this field. Summary of the invention

[0005] In view of the defects in the above-mentioned prior art, the present invention provides a capacity configuration method and system for the coordinated grid connection of gravity energy storage and electrochemical energy storage, which can quickly realize the capacity configuration of the coordinated grid connection of gravity energy storage and electrochemical energy storage.

[0006] In a first aspect, the present invention provides a capacity configuration method for coordinated grid connection of gravity energy storage and electrochemical energy storage, comprising:

[0007] Obtain the power generation signal of the power grid and perform variational mode decomposition and reconstruction to obtain the power generation signals of gravity energy storage and electrochemical energy storage;

[0008] Based on the power generation signal and power response characteristics of the gravity energy storage, determine the power range of the gravity energy storage output;

[0009] Based on the power generation signals of gravity energy storage and electrochemical energy storage, and in combination with the power range of gravity energy storage output, the power range of electrochemical energy storage output is determined;

[0010] Based on the power range of gravity energy storage and electrochemical energy storage output, the capacities of gravity energy storage and electrochemical energy storage configurations are given respectively.

[0011] Furthermore, variational mode decomposition and reconstruction are performed to obtain power generation signals of gravity energy storage and electrochemical energy storage, including:

[0012] Perform variational mode decomposition on the power generation signal to obtain multiple intrinsic mode function components arranged from low to high frequency;

[0013] Determine the cutoff point of the intrinsic mode function component based on the power generation signal of the power grid;

[0014] Based on the cutoff point of the eigenmode function components, all the eigenmode function components are divided into a first group of eigenmode function components and a second group of eigenmode function components in order of arrangement, and the frequency of the first group of eigenmode function components is less than the frequency of the second group of eigenmode function components;

[0015] The first group of intrinsic mode function components are superimposed to obtain the power generation signal of gravity energy storage, and the second group of intrinsic mode function components are superimposed to obtain the power generation signal of electrochemical energy storage.

[0016] Furthermore, the demarcation point of the intrinsic mode function component is determined based on the power generation signal of the power grid, including:

[0017] Initialize the boundary scale parameter of the variational mode decomposition, and perform variational mode decomposition on the power generation signal of the power grid to obtain multiple intrinsic mode function components;

[0018] Determining whether the center frequencies of all the intrinsic mode function components overlap according to the multiple intrinsic mode function components;

[0019] When it is judged that there is no overlap, the decomposition scale parameter is increased by one and the variational mode decomposition and judgment process is repeated until it is judged to be overlapping; when it is judged to be overlapping, the decomposition scale parameter is reduced by one and output as the final decomposition scale parameter of variational mode decomposition;

[0020] Based on the final decomposition scale parameter of variational modal decomposition, the power generation signal of the power grid is subjected to variational modal decomposition, and the central frequency distribution of all its intrinsic mode function components is determined, and the demarcation point is given.

[0021] Furthermore, the power generation signals of gravity energy storage and electrochemical energy storage satisfy the following relationship:

[0022]

[0023]

[0024] In the formula, is the power generation signal of gravity energy storage, is the power generation signal of electrochemical energy storage, m is the serial number of the demarcation point, n is the total number of intrinsic mode function components, u i (t) is the i-th intrinsic mode function component at time t.

[0025] Furthermore, based on the power generation signal and power response characteristics of the gravity energy storage, the power range of the gravity energy storage output is determined, including:

[0026] Based on the power generation signal of the gravity energy storage, determining whether the power of the gravity energy storage meets the conditions;

[0027] Based on the power response characteristics of gravity energy storage, determine the interval time between adjacent weight blocks in the gravity energy storage and the output power of the gravity energy storage at different input times;

[0028] The power range of the gravity energy storage output is determined according to the power conditions of the gravity energy storage, the interval time between the input of adjacent weight blocks in the gravity energy storage, and the output power of the gravity energy storage at different input times.

[0029] Furthermore, the power range of gravity energy storage output satisfies the following relationship:

[0030]

[0031]

[0032]

[0033] In the formula, and are the maximum power and minimum power of gravity energy storage at time t, μ is the climbing rate of gravity energy storage, Δt is the interval time between the input of adjacent weight blocks in gravity energy storage, P Gra (t-1) is the output power of gravity energy storage at time t-1, The power of gravity energy storage meets the conditions, It is the power generation signal of gravity energy storage.

[0034] Furthermore, the power range of electrochemical energy storage output satisfies the following relationship:

[0035]

[0036]

[0037] In the formula, is the maximum power of electrochemical energy storage at time t, is the minimum power of electrochemical energy storage at time t, It is the power generation signal of electrochemical energy storage.

[0038] Furthermore, the power constraint of electrochemical energy storage satisfies the following relationship:

[0039]

[0040] In the formula, The power of electrochemical energy storage meets the conditions, that is, the maximum absolute value of the power generation signal of electrochemical energy storage at time t.

[0041] Furthermore, based on the power range of gravity energy storage and electrochemical energy storage output, the capacities of gravity energy storage and electrochemical energy storage configurations are given respectively, including:

[0042] Determine the capacity of the gravity energy storage configuration based on the maximum power and minimum power of the gravity energy storage;

[0043] The capacity of the electrochemical energy storage configuration is determined based on the maximum power and minimum power of the electrochemical energy storage and combined with the charge state of the electrochemical energy storage.

[0044] Furthermore, the capacity of the gravity energy storage configuration satisfies the following relationship:

[0045]

[0046] In the formula, is the rated capacity of the gravity energy storage configuration, and T is the power generation signal acquisition period of the power grid.

[0047] Furthermore, the capacity of the electrochemical energy storage configuration satisfies the following relationship:

[0048]

[0049] In the formula, The capacity configured for electrochemical energy storage, SOC max It is the state of charge of electrochemical energy storage from the initial state of charge to the state of full charge; SOC(0) is the initial state of charge of electrochemical energy storage.

[0050] In a second aspect, the present invention further provides a capacity configuration device for the coordinated grid connection of gravity energy storage and electrochemical energy storage, and adopts the capacity configuration method for the coordinated grid connection of gravity energy storage and electrochemical energy storage, and the capacity configuration device comprises:

[0051] A decomposition and reconstruction module is used to obtain the power generation signal of the power grid and perform variational mode decomposition and reconstruction to obtain the power generation signal of gravity energy storage and electrochemical energy storage;

[0052] A gravity energy storage determination module, which is used to determine the power range of the gravity energy storage output based on the power generation signal and power response characteristics of the gravity energy storage;

[0053] An electrochemical energy storage determination module, which is used to determine the power range of the electrochemical energy storage output based on the power generation signals of the gravity energy storage and the electrochemical energy storage, and in combination with the power range of the gravity energy storage output;

[0054] The capacity configuration module is used to provide the capacity of the gravity energy storage and electrochemical energy storage configurations respectively based on the power ranges output by the gravity energy storage and the electrochemical energy storage.

[0055] Furthermore, the decomposition and reconstruction module includes:

[0056] Perform variational mode decomposition on the power generation signal to obtain multiple intrinsic mode function components arranged from low to high frequency;

[0057] Determine the cutoff point of the intrinsic mode function component based on the power generation signal of the power grid;

[0058] Based on the cutoff point of the eigenmode function components, all the eigenmode function components are divided into a first group of eigenmode function components and a second group of eigenmode function components in order of arrangement, and the frequency of the first group of eigenmode function components is less than the frequency of the second group of eigenmode function components;

[0059] The first group of intrinsic mode function components are superimposed to obtain the power generation signal of gravity energy storage, and the second group of intrinsic mode function components are superimposed to obtain the power generation signal of electrochemical energy storage.

[0060] Furthermore, the decomposition and reconstruction module also includes:

[0061] Initialize the boundary scale parameter of the variational mode decomposition, and perform variational mode decomposition on the power generation signal of the power grid to obtain multiple intrinsic mode function components;

[0062] Determining whether the center frequencies of all the intrinsic mode function components overlap according to the multiple intrinsic mode function components;

[0063] When it is judged that there is no overlap, the decomposition scale parameter is increased by one and the variational mode decomposition and judgment process is repeated until it is judged to be overlapping; when it is judged to be overlapping, the decomposition scale parameter is reduced by one and output as the final decomposition scale parameter of variational mode decomposition;

[0064] Based on the final decomposition scale parameter of variational modal decomposition, the power generation signal of the power grid is subjected to variational modal decomposition, and the central frequency distribution of all its intrinsic mode function components is determined, and the demarcation point is given.

[0065] Furthermore, the gravity energy storage determination module includes:

[0066] Based on the power generation signal of the gravity energy storage, determining whether the power of the gravity energy storage meets the conditions;

[0067] Based on the power response characteristics of gravity energy storage, determine the interval time between adjacent weight blocks in the gravity energy storage and the output power of the gravity energy storage at different input times;

[0068] The power range of the gravity energy storage output is determined according to the power conditions of the gravity energy storage, the interval time between the input of adjacent weight blocks in the gravity energy storage, and the output power of the gravity energy storage at different input times.

[0069] Furthermore, the capacity configuration module includes:

[0070] Determine the capacity of the gravity energy storage configuration based on the maximum power and minimum power of the gravity energy storage;

[0071] The capacity of the electrochemical energy storage configuration is determined based on the maximum power and minimum power of the electrochemical energy storage and combined with the charge state of the electrochemical energy storage.

[0072] The present invention provides a capacity configuration method and system for coordinated grid connection of gravity energy storage and electrochemical energy storage, which at least includes the following beneficial effects:

[0073] By determining the power range of the power response characteristics of gravity energy storage and realizing the capacity configuration of gravity energy storage, gravity energy storage can be connected to the power grid. The topological structure of directly connecting to the power grid through gravity energy storage can provide inertia for the power grid. At the same time, based on the consideration of the coordinated grid connection of gravity energy storage and electrochemical energy storage, the power range and capacity configuration of electrochemical energy storage are determined by determining the power range of gravity energy storage, and finally the coordinated grid connection of gravity energy storage and electrochemical energy storage is completed, realizing the coordinated control of power demand on the grid side. BRIEF DESCRIPTION OF THE DRAWINGS

[0074] Figure 1 A flow chart of a capacity configuration method for coordinated grid connection of gravity energy storage and electrochemical energy storage provided by the present invention;

[0075] Figure 2 A flow chart of obtaining power generation signals for gravity energy storage and electrochemical energy storage provided in one embodiment of the present invention;

[0076] Figure 3 A flow chart for determining a demarcation point provided for an embodiment of the present invention;

[0077] Figure 4 A flow chart for determining the power range of gravity energy storage output provided by an embodiment of the present invention;

[0078] Figure 5 A flow chart showing the configuration capacity of gravity energy storage and electrochemical energy storage provided for an embodiment of the present invention;

[0079] Figure 6A schematic diagram of a capacity configuration device for coordinated grid connection of gravity energy storage and electrochemical energy storage provided by the present invention. DETAILED DESCRIPTION

[0080] In order to better understand the above technical solution, the above technical solution will be described in detail below in conjunction with the accompanying drawings and specific implementation methods. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0081] The terms used in the embodiments of 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", "said" and "the" used in the embodiments of the present invention and the appended claims are also intended to include plural forms, unless the context clearly indicates other meanings, and "multiple" generally includes at least two.

[0082] It should also be noted that the term "includes", "comprising" or any other variation thereof is intended to cover non-exclusive inclusion, so that a commodity or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such commodity or device. In the absence of more restrictions, the elements defined by the sentence "comprising a ..." do not exclude the existence of other identical elements in the commodity or device including the elements.

[0083] Due to its own mechanical structure limitation, the output power characteristics of gravity energy storage present a step-type output characteristic. Gravity energy storage has a fixed interval time for the input of heavy blocks. A single gravity energy storage device is difficult to meet the real-time power demand of the grid side. The power of electrochemical energy storage can achieve smooth and continuous output. The hybrid energy storage system composed of the two can provide inertia for the grid on the one hand, and can coordinate control to achieve the power demand of the grid side on the other hand. However, there is no capacity configuration principle for the capacity configuration of the two.

[0084] Based on the above situation, if Figure 1 As shown, the present invention provides a capacity configuration method for the coordinated grid connection of gravity energy storage and electrochemical energy storage, which may include:

[0085] The power generation signal of the power grid is obtained and reconstructed by variational mode decomposition to obtain the power generation signals of gravity energy storage and electrochemical energy storage; wherein the power generation signal of the power grid is the power required by the power grid;

[0086] Based on the power generation signal and power response characteristics of the gravity energy storage, determine the power range of the gravity energy storage output;

[0087] Based on the power generation signals of gravity energy storage and electrochemical energy storage, and in combination with the power range of gravity energy storage output, the power range of electrochemical energy storage output is determined;

[0088] Based on the power range of gravity energy storage and electrochemical energy storage output, the capacities of gravity energy storage and electrochemical energy storage configurations are given respectively.

[0089] The present invention decomposes the power generation signal of the power grid into n intrinsic mode function components with frequencies from low to high through variational mode, wherein the high-frequency component is reconstructed as the automatic power generation control instruction of the electrochemical energy storage system. Low-frequency component reconstruction as automatic power generation control instructions for gravity energy storage units

[0090] Specifically, Figure 2 As shown, variational mode decomposition and reconstruction are performed to obtain power generation signals of gravity energy storage and electrochemical energy storage, which may include:

[0091] Perform variational mode decomposition on the power generation signal to obtain multiple intrinsic mode function components arranged from low to high frequency;

[0092] Determine the cutoff point of the intrinsic mode function component based on the power generation signal of the power grid;

[0093] Based on the cutoff point of the eigenmode function components, all the eigenmode function components are divided into a first group of eigenmode function components and a second group of eigenmode function components in order of arrangement, and the frequency of the first group of eigenmode function components is less than the frequency of the second group of eigenmode function components;

[0094] The first group of intrinsic mode function components are superimposed to obtain the power generation signal of gravity energy storage, and the second group of intrinsic mode function components are superimposed to obtain the power generation signal of electrochemical energy storage.

[0095] like Figure 3 As shown, the demarcation point of the intrinsic mode function component is determined based on the power generation signal of the power grid, including:

[0096] Initialize the demarcation scale parameter k of the variational modal decomposition to 2, and perform variational modal decomposition on the power generation signal of the power grid to obtain multiple intrinsic mode function components;

[0097] Determining whether the center frequencies of all the intrinsic mode function components overlap according to the multiple intrinsic mode function components;

[0098] When it is judged that there is no overlap, the decomposition scale parameter is increased by one and the variational mode decomposition and judgment process is repeated until it is judged to be overlapping; when it is judged to be overlapping, the decomposition scale parameter is reduced by one and output as the final decomposition scale parameter of variational mode decomposition;

[0099] Based on the final decomposition scale parameter of variational modal decomposition, the power generation signal of the power grid is subjected to variational modal decomposition, and the central frequency distribution of all its intrinsic mode function components is determined, and the demarcation point is given.

[0100] Among them, the power generation signals of gravity energy storage and electrochemical energy storage satisfy the following relationship:

[0101]

[0102]

[0103] In the formula, is the power generation signal of gravity energy storage, is the power generation signal of electrochemical energy storage, m is the serial number of the demarcation point, n is the total number of intrinsic mode function components, u i (t) is the i-th intrinsic mode function component at time t.

[0104] Vertical matrix gravity energy storage adopts a topological structure that is directly connected to the power grid through a synchronous machine, which can provide inertia support for the power grid. The output power of the gravity energy storage presents step and discrete characteristics. The input torque of the gravity energy storage unit is changed by the rise or fall of the weight block, thereby realizing the adjustment of the output power of the gravity energy storage.

[0105] The vertical matrix gravity energy storage system uses a transmission device to drag the elevator car, and lifts or lowers the weights through the elevator car. Its working principle is mainly to achieve electromechanical energy conversion by driving the synchronous machine through discrete weights. Due to the physical characteristics of the mechanical part of the gravity energy storage unit, there is a fixed time interval between the input / exit of each weight block, which directly affects the climbing rate of the gravity energy storage unit. The time interval between the input of each weight block in the mechanical device of the gravity energy storage is constrained as follows:

[0106] t on_i =t on_1 +(i-1)Δt

[0107] In the formula, i is the number of the weight block, t on_1 is the time for the first weight block to be put into operation, t on_i is the operation time of the i-th weight block, and Δt is the interval time of the weight blocks in the gravity energy storage.

[0108] Based on the above analysis, the power response characteristics of gravity energy storage can be clarified; at the same time, according to the power generation signal of gravity energy storage, the power constraint conditions of gravity energy storage can be satisfied:

[0109]

[0110] Specifically, Figure 4As shown, based on the power generation signal and power response characteristics of the gravity energy storage, determining the power range of the gravity energy storage output may include:

[0111] Based on the power generation signal of the gravity energy storage, determining whether the power of the gravity energy storage meets the conditions;

[0112] Based on the power response characteristics of gravity energy storage, determine the interval time between adjacent weight blocks in the gravity energy storage and the output power of the gravity energy storage at different input times;

[0113] The power range of the gravity energy storage output is determined according to the power conditions of the gravity energy storage, the interval time between the input of adjacent weight blocks in the gravity energy storage, and the output power of the gravity energy storage at different input times.

[0114] Among them, the power range of gravity energy storage output satisfies the following relationship:

[0115]

[0116]

[0117]

[0118] In the formula, and are the maximum power and minimum power output of gravity energy storage at time t, μ is the climbing rate of gravity energy storage, Δt is the interval time between the input of adjacent weight blocks in gravity energy storage, P Gra (t-1) is the output power of gravity energy storage at time t-1, The power of gravity energy storage meets the conditions, that is, the maximum absolute value of the power generation signal of gravity energy storage at time t, It is the power generation signal of gravity energy storage.

[0119] Since there are certain losses in both the energy storage equipment and the converter equipment in the process of storing and releasing electric energy in electrochemical energy storage, and considering the rapid response characteristics of electrochemical energy storage, and since the response time of the electrochemical energy storage system is much shorter than that of the gravity energy storage unit, the electrochemical energy storage system first quickly responds to the automatic power generation control command to ensure the frequency modulation effect. As the output of the gravity energy storage unit gradually increases, the electrochemical energy storage system begins to reduce power to ensure that the total power of the hybrid energy storage system of the gravity energy storage unit-electrochemical energy storage is consistent with the target power.

[0120] When the power generated by gravity energy storage Gravity energy storage power generation signal reconstructed from low-frequency components When the power generation signals of electrochemical energy storage and gravity energy storage are adjusted, the maximum power of electrochemical energy storage can be determined. When the power generated by gravity energy storage Gravity energy storage power generation signal reconstructed from low-frequency components When the power generation signals of electrochemical energy storage and gravity energy storage are adjusted, the minimum power of electrochemical energy storage can be determined.

[0121]

[0122] Based on the power generation signals of gravity energy storage and electrochemical energy storage, and combined with the power range of gravity energy storage output, the power range of electrochemical energy storage output is determined, including:

[0123] The power generation signals of gravity energy storage and electrochemical energy storage are reconstructed according to variational mode decomposition, and the maximum power and minimum power of the gravity energy storage are combined to give the maximum power and minimum power of the electrochemical energy storage output.

[0124] Among them, the power range of electrochemical energy storage output satisfies the following relationship:

[0125]

[0126]

[0127] In the formula, is the maximum power of electrochemical energy storage at time t, is the minimum power of electrochemical energy storage at time t, It is the power generation signal of electrochemical energy storage.

[0128] In addition, when determining the power range of electrochemical energy storage output, the power constraint of electrochemical energy storage also needs to be considered. According to the power allocation, the maximum power allocation (power constraint) is calculated as the output power range of electrochemical energy storage. Among them, the power constraint of electrochemical energy storage satisfies the following relationship:

[0129]

[0130] In the formula, The power of electrochemical energy storage meets the conditions, that is, the maximum absolute value of the power generation signal of electrochemical energy storage at time t.

[0131] The capacity configuration principle of gravity energy storage and electrochemical energy storage is to configure the minimum capacity under the system operating conditions. Figure 5 As shown, based on the power range of gravity energy storage and electrochemical energy storage output, the capacity of gravity energy storage and electrochemical energy storage configurations are given respectively, which may include:

[0132] Based on the maximum power and minimum power of gravity energy storage, the capacity of the gravity energy storage configuration is determined to satisfy the following relationship:

[0133]

[0134] In the formula, is the rated capacity of the gravity energy storage configuration, T is the power generation signal acquisition period of the power grid;

[0135] According to the maximum power and minimum power of electrochemical energy storage, combined with the state of charge of electrochemical energy storage, the capacity of electrochemical energy storage configuration is determined to meet the following relationship:

[0136]

[0137] In the formula, The capacity configured for electrochemical energy storage, SOC max It is the state of charge of electrochemical energy storage from the initial state of charge to the state of full charge; SOC(0) is the initial state of charge of electrochemical energy storage.

[0138] The present invention determines the power range through the power response characteristics of gravity energy storage, realizes the capacity configuration of gravity energy storage, and can connect gravity energy storage to the power grid. The topological structure of directly connecting to the power grid through gravity energy storage can provide inertia for the power grid. At the same time, based on the consideration of the coordinated grid connection of gravity energy storage and electrochemical energy storage, the power range and capacity configuration of electrochemical energy storage are quickly determined through the determined power range of gravity energy storage, and finally the coordinated grid connection of gravity energy storage and electrochemical energy storage is completed, which can quickly realize the coordinated control of power demand on the grid side.

[0139] like Figure 6 As shown, the present invention also provides a capacity configuration device for the coordinated grid connection of gravity energy storage and electrochemical energy storage, and adopts the capacity configuration method for the coordinated grid connection of gravity energy storage and electrochemical energy storage, and the capacity configuration device includes:

[0140] A decomposition and reconstruction module is used to obtain the power generation signal of the power grid and perform variational mode decomposition and reconstruction to obtain the power generation signal of gravity energy storage and electrochemical energy storage;

[0141] A gravity energy storage determination module, which is used to determine the power range of the gravity energy storage output based on the power generation signal and power response characteristics of the gravity energy storage;

[0142] An electrochemical energy storage determination module, which is used to determine the power range of the electrochemical energy storage output based on the power generation signals of the gravity energy storage and the electrochemical energy storage, and in combination with the power range of the gravity energy storage output;

[0143] The capacity configuration module is used to provide the capacity of the gravity energy storage and electrochemical energy storage configurations respectively based on the power ranges output by the gravity energy storage and the electrochemical energy storage.

[0144] Furthermore, the decomposition and reconstruction module includes:

[0145] Perform variational mode decomposition on the power generation signal to obtain multiple intrinsic mode function components arranged from low to high frequency;

[0146] Determine the cutoff point of the intrinsic mode function component based on the power generation signal of the power grid;

[0147] Based on the cutoff point of the eigenmode function components, all the eigenmode function components are divided into a first group of eigenmode function components and a second group of eigenmode function components in order of arrangement, and the frequency of the first group of eigenmode function components is less than the frequency of the second group of eigenmode function components;

[0148] The first group of intrinsic mode function components are superimposed to obtain the power generation signal of gravity energy storage, and the second group of intrinsic mode function components are superimposed to obtain the power generation signal of electrochemical energy storage.

[0149] Furthermore, the decomposition and reconstruction module also includes:

[0150] Initialize the boundary scale parameter of the variational mode decomposition, and perform variational mode decomposition on the power generation signal of the power grid to obtain multiple intrinsic mode function components;

[0151] Determining whether the center frequencies of all the intrinsic mode function components overlap according to the multiple intrinsic mode function components;

[0152] When it is judged that there is no overlap, the decomposition scale parameter is increased by one and the variational mode decomposition and judgment process is repeated until it is judged to be overlapping; when it is judged to be overlapping, the decomposition scale parameter is reduced by one and output as the final decomposition scale parameter of variational mode decomposition;

[0153] Based on the final decomposition scale parameter of variational modal decomposition, the power generation signal of the power grid is subjected to variational modal decomposition, and the central frequency distribution of all its intrinsic mode function components is determined, and the demarcation point is given.

[0154] Furthermore, the gravity energy storage determination module includes:

[0155] Based on the power generation signal of the gravity energy storage, determining whether the power of the gravity energy storage meets the conditions;

[0156] Based on the power response characteristics of gravity energy storage, determine the interval time between adjacent weight blocks in the gravity energy storage and the output power of the gravity energy storage at different input times;

[0157] The power range of the gravity energy storage output is determined according to the power conditions of the gravity energy storage, the interval time between the input of adjacent weight blocks in the gravity energy storage, and the output power of the gravity energy storage at different input times.

[0158] Furthermore, the capacity configuration module includes:

[0159] Determine the capacity of the gravity energy storage configuration based on the maximum power and minimum power of the gravity energy storage;

[0160] The capacity of the electrochemical energy storage configuration is determined based on the maximum power and minimum power of the electrochemical energy storage and combined with the charge state of the electrochemical energy storage.

[0161] Although preferred embodiments of the present invention have been described, additional changes and modifications may be made to these embodiments by those skilled in the art once the basic inventive concepts are known. Therefore, the appended claims are intended to be interpreted as including the preferred embodiments and all changes and modifications that fall within the scope of the present invention. Obviously, those skilled in the art may make various changes and modifications to the present invention without departing from the spirit and scope of the present invention. Thus, if these modifications and variations of the present invention fall within the scope of the claims of the present invention and their equivalents, the present invention is also intended to include these modifications and variations.

Claims

1. A capacity configuration method for the coordinated grid connection of gravity energy storage and electrochemical energy storage, characterized in that: include: Obtain the power generation signal of the power grid and perform variational mode decomposition and reconstruction to obtain the power generation signals of gravity energy storage and electrochemical energy storage; Based on the power generation signal and power response characteristics of the gravity energy storage, determine the power range of the gravity energy storage output; Based on the power generation signals of gravity energy storage and electrochemical energy storage, and in combination with the power range of gravity energy storage output, the power range of electrochemical energy storage output is determined; Based on the power range of gravity energy storage and electrochemical energy storage output, the capacities of gravity energy storage and electrochemical energy storage configurations are given respectively.

2. The capacity configuration method according to claim 1, characterized in that: Perform variational mode decomposition and reconstruction to obtain the power generation signals of gravity energy storage and electrochemical energy storage, including: Perform variational mode decomposition on the power generation signal to obtain multiple intrinsic mode function components arranged from low to high frequency; Determine the cutoff point of the intrinsic mode function component based on the power generation signal of the power grid; Based on the cutoff point of the eigenmode function components, all the eigenmode function components are divided into a first group of eigenmode function components and a second group of eigenmode function components in order of arrangement, and the frequency of the first group of eigenmode function components is less than the frequency of the second group of eigenmode function components; The first group of intrinsic mode function components are superimposed to obtain the power generation signal of gravity energy storage, and the second group of intrinsic mode function components are superimposed to obtain the power generation signal of electrochemical energy storage.

3. The capacity configuration method according to claim 2, characterized in that: The power generation signals of gravity energy storage and electrochemical energy storage satisfy the following relationship: In the formula, is the power generation signal of gravity energy storage, is the power generation signal of electrochemical energy storage, m is the serial number of the demarcation point, n is the total number of intrinsic mode function components, u i (t) is the i-th intrinsic mode function component at time t.

4. The capacity configuration method according to claim 1, characterized in that: Based on the power generation signal and power response characteristics of gravity energy storage, the power range of gravity energy storage output is determined, including: Based on the power generation signal of the gravity energy storage, determining whether the power of the gravity energy storage meets the conditions; Based on the power response characteristics of gravity energy storage, determine the interval time between adjacent weight blocks in the gravity energy storage and the output power of the gravity energy storage at different input times; The power range of the gravity energy storage output is determined according to the power conditions of the gravity energy storage, the interval time between the input of adjacent weight blocks in the gravity energy storage, and the output power of the gravity energy storage at different input times.

5. The capacity configuration method according to claim 4, characterized in that: The power range of gravity energy storage output satisfies the following relationship: In the formula, and are the maximum power and minimum power of gravity energy storage at time t, μ is the climbing rate of gravity energy storage, Δt is the interval time between the input of adjacent weight blocks in gravity energy storage, P Gra (t-1) is the output power of gravity energy storage at time t-1, The power of gravity energy storage meets the conditions, It is the power generation signal of gravity energy storage.

6. The capacity configuration method according to claim 5, characterized in that: The power range of electrochemical energy storage output satisfies the following relationship: In the formula, is the maximum power of electrochemical energy storage at time t, is the minimum power of electrochemical energy storage at time t; It is the power generation signal of electrochemical energy storage.

7. The capacity configuration method according to claim 1 or 6, characterized in that: Based on the power range of gravity energy storage and electrochemical energy storage output, the capacity of gravity energy storage and electrochemical energy storage configurations are given respectively, including: Determine the capacity of the gravity energy storage configuration based on the maximum power and minimum power of the gravity energy storage; The capacity of the electrochemical energy storage configuration is determined based on the maximum power and minimum power of the electrochemical energy storage and combined with the charge state of the electrochemical energy storage.

8. The capacity configuration method according to claim 7, characterized in that: The capacity of the gravity energy storage configuration satisfies the following relationship: In the formula, Rated capacity configured for gravity energy storage.

9. The capacity configuration method according to claim 7, characterized in that: The capacity of the electrochemical energy storage configuration satisfies the following relationship: In the formula, The capacity configured for electrochemical energy storage, SOC max It is the state of charge of electrochemical energy storage from the initial state of charge to the state of full charge; SOC(0) is the initial state of charge of electrochemical energy storage.

10. A capacity configuration device for the coordinated grid connection of gravity energy storage and electrochemical energy storage, characterized in that: The capacity configuration method for the coordinated grid connection of gravity energy storage and electrochemical energy storage as claimed in any one of claims 1 to 9 is adopted, and the capacity configuration device comprises: A decomposition and reconstruction module is used to obtain the power generation signal of the power grid and perform variational mode decomposition and reconstruction to obtain the power generation signal of gravity energy storage and electrochemical energy storage; A gravity energy storage determination module, which is used to determine the power range of the gravity energy storage output based on the power generation signal and power response characteristics of the gravity energy storage; An electrochemical energy storage determination module, which is used to determine the power range of the electrochemical energy storage output based on the power generation signals of the gravity energy storage and the electrochemical energy storage, and in combination with the power range of the gravity energy storage output; The capacity configuration module is used to provide the capacity of the gravity energy storage and electrochemical energy storage configurations respectively based on the power ranges output by the gravity energy storage and the electrochemical energy storage.

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