Energy storage cluster secondary frequency modulation power distribution method considering response time and soc balance

Abstract

The application discloses a kind of energy storage cluster secondary frequency modulation power distribution method and device giving consideration to response time and SOC balance, comprising: S1: according to the response time and rated capacity of energy storage unit, energy storage unit is divided into power type energy storage unit and energy type energy storage unit, according to power grid frequency deviation determines the output demand of energy storage unit;S2: according to the interval where the power grid frequency at initial time is located, the power instruction of energy storage cluster is determined to constrain the output power of energy storage cluster, and the interval objective function is solved to realize power optimization distribution.The application distinguishes the response time, rated capacity and output demand of different energy storage units, solves the corresponding objective function according to different frequency intervals to realize power optimization distribution, overcomes the technical problem that traditional power distribution method does not consider the difference in response speed between different types of energy storage units, and thus achieves the power distribution effect of giving consideration to response time and SOC balance.

Description

Technical Field

[0001] This application relates to the field of frequency regulation control technology for energy storage power stations, and in particular to a secondary frequency regulation power allocation method for energy storage clusters that takes into account both response time and SOC balance. Background Technology

[0002] Electrochemical energy storage technology boasts advantages such as flexible power throughput and high response accuracy, enabling the decoupling of power generation and consumption, transforming the power system from "rigid" to "flexible," and thus attracting significant attention in the frequency regulation field. Energy storage applications in frequency regulation can address the insufficient damping and inertial support capabilities of new energy generation. By leveraging the charging and discharging characteristics of energy storage systems, and through the large-scale, decentralized deployment and operational control of large-scale energy storage power stations, the absorption and transmission capacity of new energy sources can be effectively enhanced.

[0003] The paper by Li Junhui et al. [“Two-layer optimization of frequency regulation power for multi-energy storage systems considering frequency regulation cost and state of charge recovery” [J]. Proceedings of the CSEE, 2021, 41(23): 8020-8033] proposes a two-layer optimization strategy for frequency regulation power of multi-energy storage systems that considers frequency regulation cost and state of charge (SOC) recovery. In the frequency regulation power optimization layer, an immunity coefficient reflecting the frequency regulation capability of the energy storage power station is introduced, which, together with the frequency regulation cost, constitutes the objective function. In the SOC optimization layer, SOC weights are introduced to redistribute the frequency regulation power optimization results with the goal of restoring the SOC of the energy storage units. However, this strategy only optimizes the frequency regulation cost and SOC recovery, without considering the differences in response speed among different devices. When the regional power grid has high requirements for the transient characteristics of the frequency, this strategy cannot effectively meet the frequency regulation needs of the regional power grid.

[0004] The paper by Chen Xuemei et al. [“A Joint Frequency Regulation Control Strategy for Energy Storage-Power Unit Considering Frequency Regulation Performance Assessment” [J]. Proceedings of the CSEE, 2021, 41(10): 3383-3391] proposes a time-based control strategy for energy storage-power unit, which rationally controls the timing and depth of action of the energy storage cluster during different assessment periods, such as the initial response phase, ramp-up phase, stable phase, and non-assessment phase, thereby improving the power plant's profitability. However, this strategy only considers energy storage clusters and thermal power units as research objects and does not take into account the differences in response speed between different types of energy storage units. Summary of the Invention

[0005] To address the issue of the aforementioned strategies failing to consider the differences in response speed among different energy storage units, this invention provides a secondary frequency regulation power allocation method for energy storage clusters that balances response time and SOC equilibrium. This method selects different algorithms to complete power allocation based on the different intervals of the grid frequency at the initial moment.

[0006] According to a first aspect of the embodiments of this application, a secondary frequency regulation power allocation method for energy storage clusters that balances response time and SOC is provided, comprising:

[0007] S1: Based on the response time and rated capacity of the energy storage unit, the energy storage unit is divided into power-type energy storage unit and energy-type energy storage unit. The output demand of the energy storage unit is determined based on the grid frequency deviation.

[0008] S2: Based on the initial grid frequency range, determine the power command of the energy storage cluster to constrain its output power. Solve the objective function for the range to achieve optimal power allocation, specifically including:

[0009] 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low.

[0010] 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0011] 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0012] 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0013] Optionally, the output demand of the energy storage unit can be determined based on the grid frequency deviation, including:

[0014] The output demand of all energy storage units is determined by the sign of the regional power grid frequency deviation. When the deviation is negative, the output demand of the energy storage unit is directly proportional to the SOC (State of Charge). When the deviation is positive, the output demand of the energy storage unit is inversely proportional to the SOC.

[0015] Optionally, the power command of the energy storage cluster is determined based on the initial frequency range of the power grid, specifically including:

[0016] Set the critical values ​​x1, x2, and x3 for the dead zone and normal adjustment zone, the normal adjustment zone and the secondary emergency zone, and the secondary emergency zone and the emergency zone, respectively. Calculate the frequency deviation Δf at the current moment, and determine the interval in which the frequency deviation at the current moment falls according to the following formula:

[0017]

[0018] Where: f f For interval identification;

[0019] The power command of the energy storage cluster is determined according to the following formula:

[0020]

[0021] Where: P L P represents the total output power of the energy storage cluster at the previous moment. AGC This is an instruction from the regional power grid, where k is the proportional coefficient of the regional power grid's frequency deviation and active power deficit, and ΔP t Power commands for energy storage clusters.

[0022] Optionally, when optimizing the output power of the energy storage unit according to the power command, the output power undertaken by the power-type energy storage unit is determined according to the following formula:

[0023]

[0024] Where: ΔP t For the total output of energy storage, ΔP p This is the output of the power-type energy storage unit.

[0025] Optionally, in 2-a), the objective function for power optimization is determined according to the following equation:

[0026]

[0027] Wherein: T n Let S be the response time of the nth energy storage unit. nL S represents the state of charge of the nth energy storage unit at the previous moment. n Let ΔP be the state of charge of the nth energy storage unit at the next moment. n Let be the output power of the nth energy storage unit, and a and b be proportionality coefficients.

[0028] Optionally, in 2-b), 2-c), and 2-d), the objective function for power optimization is determined according to the following equation:

[0029]

[0030] Where: ε is a local minimum value greater than 0, t s This refers to the response time of the energy storage cluster.

[0031] According to a second aspect of the embodiments of this application, a secondary frequency regulation power distribution device for an energy storage cluster that balances response time and SOC is provided, comprising:

[0032] The preprocessing module is used to classify energy storage units into power-type energy storage units and energy-type energy storage units according to their response time and rated capacity, and to determine the output demand of the energy storage units based on the grid frequency deviation.

[0033] The power allocation module is used to determine the power command of the energy storage cluster based on the initial grid frequency range, thereby constraining the output power of the energy storage cluster. It solves the objective function for the range to achieve optimized power allocation, specifically including:

[0034] 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low.

[0035] 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0036] 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0037] 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0038] According to a third aspect of the embodiments of this application, an electronic device is provided, comprising:

[0039] One or more processors;

[0040] Memory, used to store one or more programs;

[0041] When the one or more programs are executed by the one or more processors, the one or more processors perform the method as described in the first aspect.

[0042] According to a fourth aspect of the embodiments of this application, a computer-readable storage medium is provided that stores computer instructions thereon, which, when executed by a processor, implement the steps of the method as described in the first aspect.

[0043] The technical solutions provided by the embodiments of this application may include the following beneficial effects:

[0044] As can be seen from the above embodiments, this application distinguishes the response time, rated capacity and output requirements of different energy storage units, and solves the corresponding objective function according to different frequency ranges to achieve optimized power allocation. This overcomes the technical problem that traditional power allocation methods do not consider the differences in response speed between different types of energy storage units, and thus achieves a power allocation effect that balances response time and SOC.

[0045] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and do not limit this application. Attached Figure Description

[0046] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this application and, together with the description, serve to explain the principles of this application.

[0047] Figure 1 This is a flowchart illustrating a secondary frequency regulation power allocation method for an energy storage cluster that balances response time and SOC balance, according to an exemplary embodiment.

[0048] Figure 2 This is a schematic diagram of a frequency range according to an exemplary embodiment.

[0049] Figure 3 The diagram shows simulation results under different frequency modulation commands according to an exemplary embodiment.

[0050] Figure 4 This is a simulation result diagram illustrating the discharge command following according to an exemplary embodiment.

[0051] Figure 5 This is a simulation result diagram illustrating charging command following according to an exemplary embodiment.

[0052] Figure 6This is a block diagram illustrating a secondary frequency regulation power distribution device for an energy storage cluster that balances response time and SOC, according to an exemplary embodiment. Detailed Implementation

[0053] Exemplary embodiments will now be described in detail, examples of which are illustrated in the accompanying drawings. When the following description relates to the drawings, unless otherwise indicated, the same numbers in different drawings denote the same or similar elements. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with this application. Rather, they are merely examples of apparatuses and methods consistent with some aspects of this application as detailed in the appended claims.

[0054] The terminology used in this application is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The singular forms “a,” “the,” and “the” used in this application and the appended claims are also intended to include the plural forms unless the context clearly indicates otherwise. It should also be understood that the term “and / or” as used herein refers to and includes any or all possible combinations of one or more of the associated listed items.

[0055] Figure 1 This is a flowchart illustrating a secondary frequency regulation power allocation method for an energy storage cluster that balances response time and SOC, according to an exemplary embodiment. Figure 1 As shown, the method may include the following steps:

[0056] S1: Based on the response time and rated capacity of the energy storage unit, the energy storage unit is divided into power-type energy storage unit and energy-type energy storage unit. The output demand of the energy storage unit is determined based on the grid frequency deviation.

[0057] Specifically, determining the output demand of energy storage units based on grid frequency deviation includes:

[0058] The output demand of all energy storage units is determined by the sign of the regional power grid frequency deviation. When the deviation is negative, the output demand of the energy storage unit is directly proportional to its State of Charge (SOC); when the deviation is positive, the output demand is inversely proportional to its SOC. This approach clarifies the output characteristics and output demand of the energy storage units, helping them improve their SOC during power allocation while ensuring grid frequency stability.

[0059] The power output process of the energy storage unit is simulated using the following formula:

[0060]

[0061] Wherein: T n Let C be the response time of the nth energy storage unit. n(t) represents the output power at the current moment, and the excitation is a unit step signal.

[0062] The transfer function of the energy storage unit is as follows:

[0063]

[0064] Among them: G n (s) represents the value of the nth energy storage unit in the frequency domain. The advantage of this approach is that the first-order inertial element is relatively simple, while also being able to better simulate the transient process of a real energy storage unit participating in frequency regulation.

[0065] S2: Determine the power command of the energy storage cluster based on the frequency range of the power grid at the initial moment, thereby constraining the output power of the energy storage cluster;

[0066] Specifically, the frequency deviation at the current moment is calculated according to the following formula:

[0067] Δf=f-50

[0068] Where f is the current grid frequency, and Δf is the current frequency deviation.

[0069] Define the charge / discharge identifier as follows:

[0070]

[0071] Where: α f For charging and discharging indication, α f When α is 1, the energy storage cluster needs to participate in frequency regulation through discharge. f When the value is -1, the energy storage cluster needs to participate in frequency regulation through charging.

[0072] Calculate the current active power deficit using the following formula:

[0073] ΔP=kΔf

[0074] Where: k is the proportional coefficient, and ΔP is the current active power deficit, which needs to be compensated by the charging and discharging of the energy storage cluster.

[0075] refer to Figure 2 Set the critical values ​​x1, x2, and x3 for the dead zone and normal adjustment zone, the normal adjustment zone and the secondary emergency zone, and the secondary emergency zone and the emergency zone, respectively. Calculate the frequency deviation Δf at the current moment, and determine the interval in which the frequency deviation at the current moment falls according to the following formula:

[0076]

[0077] Where: f fThis serves as a range identifier; the advantage of doing so is that it clarifies the frequency regulation needs of the power grid at the current moment, enabling the energy storage cluster to determine the power allocation scheme based on the frequency regulation needs.

[0078] The power command of the energy storage cluster is determined according to the following formula:

[0079]

[0080] Where: P L P represents the total output power of the energy storage cluster at the previous moment. AGC This is an instruction from the regional power grid, where k is the proportional coefficient of the regional power grid's frequency deviation and active power deficit, and ΔP t This is the power command for the energy storage cluster. The advantage of this is that when the grid frequency is initially in the emergency regulation zone, the energy storage unit can quickly output power to restore the frequency.

[0081] The additional frequency regulation power required for an energy storage cluster consists of two parts: the additional frequency regulation power from power-type energy storage units and the additional frequency regulation power from energy-type energy storage units, as shown below:

[0082]

[0083] Where: ΔP p The additional frequency regulation power required for power-type energy storage, ΔP e The additional frequency regulation power required for energy storage, ΔP n The frequency regulation power required to add for the nth energy storage unit.

[0084] For a single energy storage unit, the output power at the current moment is calculated according to the following formula:

[0085]

[0086] Where: P nL P represents the output power of the nth energy storage unit at the previous moment. n (t) represents the output power of the nth energy storage unit at the current time.

[0087] The transient process is considered complete when the output power of the energy storage cluster reaches 95% of its steady-state value. The response time of the energy storage cluster is determined using the following formula:

[0088]

[0089] The advantage of doing this is that it determines the response time of the energy storage cluster in a relatively simple way, which is beneficial for subsequent power adjustments.

[0090] The power allocation is optimized by solving the objective function for the interval, specifically including:

[0091] 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low.

[0092] Specifically, the objective function for power optimization is determined according to the following formula:

[0093]

[0094] Wherein: S nL S represents the state of charge of the nth energy storage unit at the previous moment. n Let ΔP be the state of charge of the nth energy storage unit at the next moment. n Let be the output power of the nth energy storage unit, and a and b be proportionality coefficients.

[0095] The above objective function is essentially a synthesis of two basic objective functions. These two basic objective functions reflect the response time and SOC balance of the energy storage cluster, but they differ in magnitude. To ensure that the synthesized objective function can take into account both response time and SOC balance, the scaling factor needs to satisfy the following constraints:

[0096]

[0097] The advantage of doing this is that it normalizes the two basic objective functions, resulting in a synthetic objective function that balances response time and SOC.

[0098] 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0099] Specifically, the proportion of power output of the power-type energy storage unit in the total energy storage output is determined according to the following formula:

[0100]

[0101] It should be noted that this formula describes not only the proportion of power-type energy storage unit output in the total energy storage output in the normal regulation zone, but also the proportion of power-type energy storage unit output in the total energy storage output in the secondary emergency zone and the emergency zone.

[0102] The objective function for power optimization is determined based on the following formula:

[0103]

[0104] Wherein: S nL S represents the state of charge of the nth energy storage unit at the previous moment. n Let t be the state of charge of the nth energy storage unit at the next time step, where ε is a local minimum value greater than 0. s Let represent the response time of the energy storage cluster. It should be noted that the objective functions for the secondary emergency zone and the emergency zone are the same as in the above equation. The advantage of this approach is that it ensures the energy storage cluster completes secondary frequency regulation in the shortest possible time, while also considering the impact of SOC on power allocation.

[0105] The mathematical relationship between the states of charge at the previous and next time steps is determined by the following formula:

[0106]

[0107] Where: E n η is the rated capacity of the nth energy storage unit. n Let ΔP be the efficiency of the nth energy storage unit, T be the update cycle of the automatic generation control command, and ΔP be the value of ΔP. n (t) represents the output power of the nth energy storage unit.

[0108] Considering the practical physical significance of energy storage units, it is necessary to protect their state of charge and prevent overcharging or over-discharging. Therefore, the following constraints must be met:

[0109] S min ≤S n ≤S max

[0110] Wherein: S max S is the maximum safe value for the state of charge. min This is the minimum safe value for the state of charge.

[0111] The output power of an energy storage unit is limited by its rated power, therefore the following constraints must be met:

[0112] 0≤P n ≤P N,n

[0113] Where: P N,n This represents the rated power of the nth energy storage unit.

[0114] It should be noted that the power constraints and SOC constraints mentioned above apply to the entire secondary frequency regulation process. Therefore, secondary frequency regulation in different intervals is subject to the same power constraints and SOC constraints. The advantage of this approach is that it ensures the safety and stability of the power grid while solving the optimization problem.

[0115] 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0116] Specifically, this step can be referred to in 2-b), and will not be elaborated here.

[0117] 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0118] Specifically, this step can be referred to in 2-b), and will not be elaborated here.

[0119] The feasibility of a secondary frequency regulation power allocation method for energy storage clusters that balances response time and SOC was tested on the experimental platform. The basic parameters of the energy storage cluster are shown in Table 1.

[0120] Table 1 Basic Parameters of Energy Storage Cluster

[0121] SOC 0.6 0.47 0.75 0.52 0.33 T(s) 0.05 0.05 0.1 0.2 0.4 P(MW) / E(MWh) 3 / 1 3 / 1 2.5 / 2 2 / 2 1.5 / 4 Unit 6 Unit 7 Unit 8 Unit 9 Unit 10 SOC 0.39 0.56 0.65 0.8 0.65 T(s) 0.4 0.4 0.8 1 1 P(MW) / E(MWh) 1.2 / 5 0.8 / 6 1.4 / 8 1.2 / 10 1 / 10

[0122] Figure 3 The simulation results are shown below for different frequency modulation commands. It can be seen that designing different frequency modulation commands affects the response time of the energy storage cluster. During discharge, the higher frequency modulation command can effectively shorten the response time. Therefore, when the initial frequency is in the emergency adjustment zone, the corresponding frequency modulation command can be designed according to the upper boundary of the dead zone.

[0123] Figure 4 The figure shows the simulation results of discharge command following according to an example of the present invention. It can be seen that the frequency is in the emergency adjustment zone at the initial moment. At this time, the power storage unit undertakes all the output. After basically entering the steady state, the output composition is adjusted according to the dead zone control strategy. Some power storage units reduce their output to maintain discharge mobility, while some energy storage units increase their output to improve the state of charge.

[0124] Figure 5 The figure shows the simulation results of charging command following according to an example of the present invention. It can be seen that the frequency is in the secondary emergency adjustment zone at the initial moment. At this time, the power storage takes on most of the output to shorten the response time. After basically entering steady state, the output composition is adjusted according to the dead zone control strategy to take into account the response time and SOC balance of the energy storage cluster.

[0125] As can be seen from the above embodiments, this application distinguishes the response time, rated capacity and output requirements of different energy storage units, and solves the corresponding objective function according to different frequency ranges to achieve optimized power allocation. This overcomes the technical problem that traditional power allocation methods do not consider the differences in response speed between different types of energy storage units, and thus achieves a power allocation effect that balances response time and SOC.

[0126] Corresponding to the aforementioned embodiments of the energy storage cluster secondary frequency regulation power allocation method that takes into account both response time and SOC balance, this application also provides embodiments of the energy storage cluster secondary frequency regulation power allocation device that takes into account both response time and SOC balance.

[0127] Figure 6 This is a block diagram illustrating a secondary frequency regulation power distribution device for an energy storage cluster that balances response time and SOC (State of Charge) according to an exemplary embodiment. (Refer to...) Figure 6 The device includes:

[0128] Preprocessing module 1 is used to classify energy storage units into power-type energy storage units and energy-type energy storage units according to the response time and rated capacity of the energy storage units, and to determine the output demand of the energy storage units according to the grid frequency deviation.

[0129] Power allocation module 2 is used to determine the power command of the energy storage cluster based on the grid frequency interval at the initial moment, thereby constraining the output power of the energy storage cluster. It solves the objective function for the interval to achieve optimized power allocation, specifically including:

[0130] 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low.

[0131] 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0132] 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0133] 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a).

[0134] Regarding the apparatus in the above embodiments, the specific manner in which each module performs its operation has been described in detail in the embodiments related to the method, and will not be elaborated upon here.

[0135] For the device embodiments, since they basically correspond to the method embodiments, the relevant parts can be referred to in the description of the method embodiments. The device embodiments described above are merely illustrative. The units described as separate components may or may not be physically separate, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed across multiple network units. Some or all of the modules can be selected to achieve the purpose of this application according to actual needs. Those skilled in the art can understand and implement this without creative effort.

[0136] Accordingly, this application also provides an electronic device, comprising: one or more processors; a memory for storing one or more programs; and when the one or more programs are executed by the one or more processors, the one or more processors implement the above-described energy storage cluster secondary frequency regulation power allocation method that balances response time and SOC balance.

[0137] Accordingly, this application also provides a computer-readable storage medium storing computer instructions that, when executed by a processor, implement the above-described energy storage cluster secondary frequency modulation power allocation method that balances response time and SOC balance.

[0138] Other embodiments of this application will readily occur to those skilled in the art upon consideration of the specification and practice of the disclosure herein. This application is intended to cover any variations, uses, or adaptations of this application that follow the general principles of this application and include common knowledge or customary techniques in the art not disclosed herein. The specification and embodiments are to be considered exemplary only, and the true scope and spirit of this application are indicated by the claims.

[0139] It should be understood that this application is not limited to the precise structure described above and shown in the accompanying drawings, and various modifications and changes can be made without departing from its scope. The scope of this application is limited only by the appended claims.

Claims

1. A method for secondary frequency modulation power distribution of energy storage clusters that balances response time and SOC, characterized in that, include: S1: Based on the response time and rated capacity of the energy storage unit, the energy storage unit is divided into power-type energy storage unit and energy-type energy storage unit. The output demand of the energy storage unit is determined based on the grid frequency deviation. S2: Based on the initial grid frequency range, determine the power command of the energy storage cluster to constrain its output power. Solve the objective function for the range to achieve optimal power allocation, specifically including: 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low. 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). In 2-a), the objective function for power optimization is determined according to the following equation: ； in: T n For the first n The response time of each energy storage unit S nL For the previous moment n The state of charge of each energy storage unit S n For the next moment n The state of charge of each energy storage unit, Δ P n For the first n The output power of each energy storage unit a and b This is the proportionality coefficient; In 2-b), 2-c), and 2-d), the objective function for power optimization is determined according to the following formula: ； in: ε It is a local minimum value greater than 0. t s This refers to the response time of the energy storage cluster.

2. The method according to claim 1, characterized in that, Determining the output demand of energy storage units based on grid frequency deviation includes: The output demand of all energy storage units is determined by the sign of the regional power grid frequency deviation. When the deviation is negative, the output demand of the energy storage unit is directly proportional to the SOC (State of Charge). When the deviation is positive, the output demand of the energy storage unit is inversely proportional to the SOC.

3. The method according to claim 1, characterized in that, Based on the initial frequency range of the power grid, the power command for the energy storage cluster is determined, specifically including: Set the critical values ​​for the dead zone and normal adjustment zone, the normal adjustment zone and the secondary emergency zone, and the secondary emergency zone and the emergency zone respectively. x 1. x 2. x 3. Calculate the frequency deviation Δ at the current moment. f Determine the frequency deviation interval at the current moment using the following formula: ； in: f f For interval identification; The power command of the energy storage cluster is determined according to the following formula: ； in: P L This represents the total output power of the energy storage cluster at the previous moment. P AGC Instructions for the regional power grid, k Δ is the proportionality coefficient between the regional power grid frequency deviation and the active power deficit. P t Power commands for energy storage clusters.

4. The method according to claim 1, characterized in that, When optimizing the output power of the energy storage unit according to the power command, the output power undertaken by the power-type energy storage unit is determined according to the following formula: ； Where: Δ P t For the total output of energy storage, Δ P p This is the output of the power-type energy storage unit.

5. A secondary frequency regulation power distribution device for an energy storage cluster that balances response time and SOC, characterized in that, include: The preprocessing module is used to classify energy storage units into power-type energy storage units and energy-type energy storage units according to their response time and rated capacity, and to determine the output demand of the energy storage units based on the grid frequency deviation. The power allocation module is used to determine the power command of the energy storage cluster based on the initial grid frequency range, thereby constraining the output power of the energy storage cluster. It solves the objective function for the range to achieve optimized power allocation, specifically including: 2-a) If the grid frequency is within the dead zone, design a power command so that the grid frequency remains within the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit reduces its output power to 0, and the energy-type energy storage unit makes up for this part of the output power in order of output demand from high to low. 2-b) If the grid frequency is within the normal regulation range, design a power command so that the grid frequency reaches 50Hz in steady state; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit and the energy-type energy storage unit can bear the same amount of output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). 2-c) If the grid frequency is located in the sub-emergency zone, design a power command so that the grid frequency approaches the boundary of the dead zone in steady state; optimize the output power of the energy storage unit according to the power command so that the output power of the power-type energy storage unit is greater than the output power of the energy-type energy storage unit; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). 2-d) If the grid frequency is in the emergency zone, design a power command so that the grid frequency reaches the boundary of the dead zone; optimize the output power of the energy storage unit according to the power command so that the power-type energy storage unit can bear all the output power; after entering steady state, adjust the output power according to the power command and power optimization method in 2-a). In 2-a), the objective function for power optimization is determined according to the following equation: ； in: T n For the first n The response time of each energy storage unit S nL For the previous moment n The state of charge of each energy storage unit S n For the next moment n The state of charge of each energy storage unit, Δ P n For the first n The output power of each energy storage unit a and b This is the proportionality coefficient; In 2-b), 2-c), and 2-d), the objective function for power optimization is determined according to the following formula: ； in: ε It is a local minimum value greater than 0. t s This refers to the response time of the energy storage cluster.

6. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1-4.

7. A computer-readable storage medium storing computer instructions thereon, characterized in that, When executed by the processor, this instruction implements the steps of the method as described in any one of claims 1-4.

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