A power allocation strategy for energy consumption optimization in energy storage power plants

Abstract

The present invention discloses a power allocation strategy for optimizing energy consumption of energy storage power stations, including: according to the acquired command power P target The output battery group is determined by the health status SOH and state of charge SOC of each battery group in the current target energy storage power station; the state of charge SOC of each output battery group is input into the pre-established objective function containing constraints and capable of optimizing multiple objectives at the same time, and the output power P of each output battery group is obtained, and the output power P of each output battery group is allocated to the corresponding output battery group; wherein, the multiple objectives include minimum energy consumption of the power station, best economic efficiency of the power station and longest life of the power station; the constraints include the command power P target Constraints, output power P constraints for each output battery group, and state of charge (SOC) constraints for each output battery group. This invention takes power station energy consumption, economy, and lifespan as optimization goals, effectively ensuring that the energy efficiency of the energy storage power station reaches or approaches the rated energy efficiency under various operating conditions.

Description

Technical Field

[0001] The present invention belongs to the technical field of energy consumption optimization of energy storage power stations, and more specifically, relates to a power allocation strategy for energy consumption optimization of energy storage power stations. Background Art

[0002] As my country's energy structure transforms, its power system is exhibiting new characteristics such as a high proportion of renewable energy and a high degree of power electronics. The proportion of thermal power units in these new power systems is decreasing, resulting in insufficient system inertia and the need for a large number of flexible and fast-adjustable resources. Energy storage is an effective means of addressing the stability challenges of these new power systems. Its scale is continuously increasing, and its application scenarios are becoming increasingly complex. For example, when energy storage power stations are used for peak load regulation, they generally operate under rated conditions and have an efficiency of approximately 85%. However, when energy storage power stations are used to respond to system frequency regulation needs, they track system demand and maintain system frequency stability through rapid charging and discharging. In this case, the energy storage power stations operate under non-rated conditions, and their efficiency drops significantly, to approximately 60-80%. Therefore, there is an urgent need to improve the energy efficiency of large-scale energy storage power stations, especially those operating under non-rated conditions.

[0003] Currently, power allocation strategies for energy storage power plants primarily consider constraints such as battery state of charge and health, often prioritizing optimal economic performance with relatively little attention paid to plant efficiency. The energy efficiency levels of various components of an energy storage power plant are directly related to its operating state, resulting in significant variations in efficiency levels under different operating conditions. Plant efficiency is closely linked to plant economics and also impacts its operational lifespan. Summary of the Invention

[0004] In response to the shortcomings of the existing technology, the purpose of the present invention is to provide a power allocation strategy and system for optimizing the energy consumption of energy storage power stations, taking the energy consumption, economy and life of the power station as optimization goals, which can effectively ensure that the energy efficiency of the energy storage power station under various operating conditions reaches or is close to the rated energy efficiency.

[0005] To achieve the above objectives, the present invention provides a power allocation strategy for optimizing energy consumption of energy storage power stations, comprising the following steps:

[0006] (1) According to the obtained command power P targe t and the health status SOH and charge status SOC of each battery pack in the current target energy storage power station, determine the output battery pack; the command power P target This is the dispatching command power issued by the power grid or the power that the target energy storage power station needs to provide under active support;

[0007] (2) Inputting the state of charge (SOC) of each output battery group into a pre-established objective function that includes constraints and can simultaneously optimize multiple objectives, obtaining the output power P of each output battery group, and allocating the output power P of each output battery group to the corresponding output battery group; wherein the multiple objectives include minimizing power station energy consumption, optimizing power station economy, and maximizing power station life; the constraints include the command power P target Constraints, output power P constraints of each output battery group and state of charge SOC constraints of each output battery group.

[0008] The power allocation strategy for energy storage power station energy consumption optimization provided by the present invention takes energy storage power station energy consumption as the primary optimization target, while taking into account the power station economy and power station life, in order to meet the command power P target The output power P limit of each output battery group and the state of charge SOC limit of each output battery group are used as basic operating constraints. A multi-objective optimization function considering energy consumption, economy and power station life is established, which can effectively ensure that the energy efficiency of the energy storage power station under various working conditions reaches or is close to the rated energy efficiency.

[0009] In one embodiment, step (1) specifically includes:

[0010] (1) According to the command power P target The rated power P of the target energy storage station N , determine the number n of battery packs required to operate in the target energy storage power station;

[0011] (2) judging the abnormal battery groups and their number in the target energy storage power station according to the health status SOH of each battery group, and determining the workable battery groups and their number m in the target energy storage power station according to the abnormal battery groups and their number;

[0012] (3) When the number m of the workable battery packs is greater than or equal to the required number n of battery packs, a battery pack is selected from the workable battery packs at the current command power P. target The top n battery packs in the charge / discharge efficiency ranking are the output battery packs; otherwise, all the workable battery packs are the output battery packs.

[0013] In one embodiment, the expression for the required number of battery packs to be operated n=f(N) in step (1) is:

[0014]

[0015] Wherein, N is the total number of battery packs in the target energy storage power station; [·] represents a rounding function, the value of which is the largest integer not greater than “·”; when N is the integer part of 4, a is 0, otherwise a is 1.

[0016] In one embodiment, in step (3), when the number m of operable battery packs is greater than or equal to the required number n of battery packs, the step of determining the output battery pack is specifically as follows:

[0017] When the current command power P target When the value is negative, the battery packs with a state of charge (SOC) between 20% and 60% among the workable battery packs are preferentially selected as the output battery packs. If the number of battery packs with a state of charge (SOC) between 20% and 60% is less than the required number of battery packs n, the battery packs with a state of charge (SOC) lower than 20% are preferentially selected from the workable battery packs as the output battery packs.

[0018] When the current command power P target When it is a positive value, the battery packs with a state of charge SOC between 40% and 80% in the workable battery packs are preferentially selected as the output battery packs. If the number of battery packs with a state of charge SOC between 40% and 80% is less than the required number of battery packs n, the battery packs with a state of charge SOC higher than 80% are preferentially selected from the workable battery packs as the output battery packs.

[0019] In one embodiment, the expression for selecting the output battery pack from the workable battery packs is:

[0020]

[0021] Where, SOC k is the state of charge SOC of the kth battery pack in the working battery pack. When the command power P target When the command power is positive, the output battery group is selected in the order of partition number 4, 5, 3, 6, and 2; when the command power is negative, the output battery group is selected in the order of partition number 3, 2, 4, 1, and 5, and the battery groups in the same partition number are selected in the order of |SOC k |Select the value from small to large.

[0022] In one embodiment, the objective function is expressed as:

[0023] minF=w1f loss +w2f cost +w3f life

[0024] Wherein, w1 / w2 / w3 represent weight coefficients, and the weight coefficients are assigned by the hierarchical analysis method;

[0025] f loss Indicates the energy consumption of the power station, according to the energy consumption of the battery pack C B 、PCS energy consumption C PCS , Energy consumption of electrical equipment in the station C airThe energy efficiency level under different operating conditions is established based on the overall output power P of the power station. total , a function related to the output power P of each battery pack in the output battery pack;

[0026] f cost The economic efficiency of the power station is established based on the initial construction cost, operation cost and external service income of the power station, which is related to the overall output power P of the power station. total , a function related to service mileage S and the number of days used t;

[0027] f life The life of the power station is established based on the natural life loss and action life loss of the power station, and is related to the overall output power P of the power station. total And functions related to the number of days t used.

[0028] In one embodiment, the power station energy consumption f loss The expression is:

[0029] f loss (P i )=C B +C PCS +C air =α i P i +β i P i +γP total

[0030] α i The expression is:

[0031]

[0032] β i The expression is:

[0033]

[0034] The expression of γ is:

[0035]

[0036] Where, α i represents the energy efficiency correction value of the i-th battery group in the output battery group; represents the energy efficiency level of the i-th battery pack; represents the correction amount of the energy efficiency of the i-th battery pack affected by the SOC, and its segmented values ​​are obtained based on the actual characteristics and measurement values ​​of the battery pack; represents the operating voltage / open circuit voltage across the i-th battery pack; P i represents the output power of the i-th battery pack; SOC irepresents the state of charge SOC of the i-th battery pack;

[0037] β i represents the energy efficiency correction of the j-th PCS; It represents the correction amount of the j-th PCS affected by the output power; represents the energy efficiency level of the j-th PCS; Indicates the DC side / AC side power value of the j-th PCS;

[0038] γ represents the energy efficiency correction of electrical equipment in the station.

[0039] In one embodiment, the power station economic efficiency f cost The expression is:

[0040]

[0041] Where C O represents the total investment in power plant construction; Y represents the expected life of the power plant; C run is the power station operation cost function; R represents the external service revenue function.

[0042] In one embodiment, the power station life f life The expression is:

[0043] f life =L BESS (t)+L run P total

[0044] Where, L BESS (t) represents the function of battery natural aging over time; L run Indicates running the depreciated life function.

[0045] In one embodiment, the constraint condition is expressed as:

[0046]

[0047] Where, P max-c，i / P min-c，i Indicates the maximum / minimum charging power of the i-th battery pack in the output battery pack; P max-d，i / P min-c，i Indicates the maximum / minimum discharge power of the i-th battery pack; represents the minimum / maximum constraint value of the state of charge (SOC) of the i-th battery pack; D represents the number of output battery packs. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] Figure 1This is a flow chart of a power allocation strategy for optimizing energy consumption in an energy storage power station according to an embodiment;

[0049] Figure 2 This is a schematic structural diagram of an energy storage power station in one embodiment;

[0050] Figure 3 This is a schematic diagram of a relationship matrix used to calculate weight coefficients using the hierarchical analysis method in one embodiment. DETAILED DESCRIPTION

[0051] In order to make the purpose, technical solutions and advantages of the present invention more clearly understood, the present invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not intended to limit the present invention.

[0052] Figure 1 FIG. 1 is a flow chart of a power allocation strategy for optimizing energy consumption in an energy storage power station according to an embodiment of the present invention. Figure 1 As shown, the power allocation strategy includes steps S10 to S40, which are described in detail as follows:

[0053] S10, according to the obtained command power P target And the health status SOH and charge status SOC of each battery group in the current target energy storage power station, determine the output battery group. Among them, the command power P target It is the dispatching command power issued by the power grid or the power that the target energy storage power station needs to provide under active support.

[0054] In this embodiment, the command power P target Determine the required number n of operating battery packs in the power station; then, identify abnormal battery packs in the power station based on the health status SOH of each battery pack, and subtract the number of abnormal battery packs from the total number N of battery packs in the power station to obtain the number m of workable battery packs in the power station; when the number m of workable battery packs is greater than or equal to the required operating number n, n battery packs can be selected from the workable battery packs as output battery packs for output response based on the state of charge SOC of each battery pack in the workable battery packs; when the number m of workable battery packs is less than the required operating number n, all battery packs in the workable battery packs are used as output battery packs for output response.

[0055] Compared with the traditional command power P targetThe output battery group is determined by the state of charge (SOC) of each battery group. This embodiment incorporates the state of health (SOH) of each battery group. Obtaining the SOH of each battery group is primarily used to analyze the health of each battery group and promptly replace aging battery groups (abnormal battery groups), which can reduce energy consumption and improve the energy efficiency of energy storage power stations. Specifically, the SOH of each battery group can be determined based on the internal resistance of each battery group. When the internal resistance of a battery group exceeds a set threshold, the battery group is prohibited from performing the current output response. After the current output response ends, the battery group is promptly replaced.

[0056] S20, input the determined state of charge (SOC) of the output battery group into a pre-established objective function that includes constraints and can simultaneously optimize multiple objectives, obtain the output power P of each output battery group, and allocate the output power P of each output battery group to the corresponding output battery group. Among them, the multiple objectives include minimum power station energy consumption, best power station economy and longest power station life; the constraints include the command power P target Constraints, output power P constraints of each output battery group and state of charge SOC constraints of each output battery group.

[0057] It should be noted that traditional energy storage power stations are all aimed at economy, without considering the energy consumption and life of the power station, which leads to large differences in the energy efficiency levels of the power station under different operating conditions.

[0058] The power allocation strategy for energy storage power station energy consumption optimization provided in this embodiment takes energy storage power station energy consumption as the primary optimization target, while taking into account the power station economy and power station life to meet the command power P target The output power P limit of each output battery group and the state of charge SOC limit of each output battery group are used as basic operating constraints. A multi-objective optimization function considering energy consumption, economy and power station life is established, which can effectively ensure that the energy efficiency of the energy storage power station under various working conditions reaches or is close to the rated energy efficiency.

[0059] In a specific embodiment, the detailed steps of the power allocation strategy for optimizing energy consumption of energy storage power stations provided by the present invention are as follows:

[0060] (1) Obtaining command power P target Among them, the command power P target It is the dispatching command power issued by the power grid or the power that the target energy storage power station needs to provide under active support.

[0061] (2) Obtain the health status (SOH) and state of charge (SOC) of each battery pack in the current target energy storage power station.

[0062] The state of health (SOH) of each battery pack helps understand its health and facilitates timely replacement of aging batteries. The energy storage system's battery management system monitors the internal resistance of each battery pack. If a battery pack's internal resistance is too high, it is considered abnormal and prohibited from responding to the current output. After the current output response is complete, it is promptly replaced, minimizing energy consumption in the energy storage power station.

[0063] (3) Determine the output battery pack

[0064] (1) According to the command power P target The rated power P of the power station N , determine the number n of battery packs required to operate in the power station.

[0065] Specifically, if the structure of the target energy storage power station is as follows Figure 2 As shown, there are N battery packs, and the PCSs of the workstations are operated in parallel. The required number of battery packs n = f(N) is expressed as:

[0066]

[0067] Where N is the total number of battery packs in the target energy storage power station; P N is the rated power of the target energy storage power station; when N is the integer part of 4, a is 0, otherwise a is 1; [·] represents the rounding function, which takes the maximum integer not greater than “·”. The value selection idea is that the proportion of the required number of battery packs n (relative to the total number of battery packs N) is equal to the command power Pt arget Ratio (relative to rated power P N ), when [·]+a is taken, the two are equal, which can make each battery pack in the energy storage power station work at the rated state as much as possible to avoid overcharge and overdischarge. For example, when the command power P target =0.2P N According to the above expression, there should be (total number of battery packs N / 4)+1 battery packs receiving instructions to output power.

[0068] (2) Determine the abnormal battery groups and their number in the power station based on the health status SOH of each battery group, and determine the workable battery groups and their number m in the power station based on the abnormal battery groups and their number.

[0069] (3) Determine whether the number of working battery packs meets the output requirements.

[0070] Subtract the number of abnormal battery groups from the total number of battery groups N in the power station and calculate the difference between the number of required battery groups n. If the value is negative, all working battery groups will be used as output battery groups for output response; if the value is positive or zero, the working battery groups will be selected from the current command power P. targetThe top n battery packs in terms of charge / discharge efficiency are the output battery packs. Their purpose is to ensure that the battery packs with response advantages have priority in output, to ensure that the battery packs operate in the SOC segment with a higher energy efficiency level (40%-60%), and to balance the SOC status of each battery pack to a certain extent.

[0071] Furthermore, when the number m of operable battery packs is greater than or equal to the required number n of operating battery packs, the step of determining the output battery pack may be:

[0072] When the current command power P target When it is a negative value, the battery packs with a state of charge SOC between 20% and 60% among the workable battery packs are preferentially selected as the output battery packs. If the number of battery packs with a state of charge SOC between 20% and 60% is less than the required number of battery packs n, the battery packs with a state of charge SOC lower than 20% are preferentially selected from the workable battery packs as the output battery packs.

[0073] When the current command power P target When it is a positive value, the battery packs with a state of charge SOC between 40% and 80% among the workable battery packs are preferentially selected as the output battery packs. If the number of battery packs with a state of charge SOC between 40% and 80% is less than the required number of battery packs n, the battery packs with a state of charge SOC higher than 80% are preferentially selected from the workable battery packs as the output battery packs.

[0074] It should be noted that the command power P target A positive value indicates that the current grid active power is insufficient and the energy storage needs to be discharged; otherwise, the command power P target A negative value indicates that the active power of the grid is too large and the energy storage needs to be charged.

[0075] The charge and discharge capabilities of the battery pack are as follows: when charging, the state of charge SOC of 0-20% is the best, 20-40% is good, 40-60% is average, 60-80% is poor, and 80-100% is poor; when discharging, the state of charge SOC of 0-20% is poor, 20-40% is poor, 40-60% is average, 60-80% is good, and 80-100% is the best.

[0076] The energy efficiency level of the battery pack is as follows: the state of charge SOC of 0-20% and 80-100% is poor, 20-40% and 60-80% is average, and 40-60% is the best.

[0077] Considering the energy efficiency level, charge and discharge capacity and battery SOC balance, the battery pack output order is as follows: the highest priority, the second priority, the general, the second least priority, the no priority five partitions, the determination rules are as follows: the command power P targetIf it is a positive value, the state of charge SOC is 50-60% with the best energy efficiency and average discharge capacity, which is the highest priority output area; the state of charge SOC is 60-80% with average energy efficiency and good discharge capacity, which is the second priority output area; the state of charge SOC is 40-50% with the best energy efficiency and average discharge capacity, which is the general output area; the state of charge SOC is 80-100% with poor energy efficiency and the best discharge capacity, which is the second non-priority output area; the state of charge SOC is 0-20% with poor energy efficiency and poor discharge capacity, which is the non-priority output area. On the contrary, the command power P target When the value is negative, the sorting is similar as follows.

[0078] Then the expression for selecting the output battery group from the working battery group can be:

[0079]

[0080] Where, SOC k is the state of charge SOC of the kth battery pack in the working battery pack. When the command power P target When the command power is positive, the output battery group is selected in the order of partition number 4, 5, 3, 6, and 2; when the command power is negative, the output battery group is selected in the order of partition number 3, 2, 4, 1, and 5, and the battery groups in the same partition number are selected in the order of |SOC k |Select the value from small to large.

[0081] For example: A power station has 8 battery packs connected in parallel, and its power instruction P target is a positive value, and according to the power instruction P target It has been determined that the number of battery packs required for operation is 5. The battery pack numbers and SOC status are as follows:

[0082] battery pack 1 2 3 4 5 6 7 8 SOC status 65％ 45％ 60％ 55％ 85％ 62％ 64％ 70％ Differential partition number 5 3 5 4 6 5 5 5

[0083] After feedback on the health status SOH parameters of each battery group, there is no abnormal battery group, so it can be determined that the five battery groups with power output are battery groups 4, 3, 6, 7, and 1.

[0084] (IV) Calculate the output power P of each output battery group

[0085] (1) Objective function: (Multi-objective) Minimum energy consumption, best economy, and longest life. Its expression is as follows:

[0086] minF=w1f loss +w2f cost +w3f life

[0087]

[0088] In the formula, w1 / w2 / w3 represent weight coefficients, which can be assigned by the hierarchical analysis method, that is, it is necessary to establish Figure 3 The relationship matrix of the form is solved step by step, where c1 / c2 / c3 represent the quantities whose weight values ​​need to be judged, namely, minimum energy consumption, best economy, and longest life. uv Indicates the importance of u compared to v, which needs to be assigned based on subjective experience or needs, and b uv with b vu They are reciprocals of each other. b uv The value of can be between 1 and 9. The more important u is relative to v, the larger the value. The weight coefficient can be obtained by solving the eigenvalue and corresponding eigenroot of the matrix, normalizing the eigenvector and performing corresponding tests.

[0089] f loss Indicates the energy consumption of the power station, based on the energy consumption of the battery pack C B 、PCS energy consumption C PCS , Energy consumption of electrical equipment in the station C air The energy efficiency level under different operating conditions is established based on the overall output power P of the power station. total , a function related to the output power P of each battery pack in the output battery pack.

[0090] f cost It represents the economic efficiency of the power station, which is established based on the initial construction cost, operation cost and external service income of the power station. It is related to the overall output power P of the power station. total , a function related to service mileage S and the number of days used t.

[0091] f life Indicates the life of the power station, which is established based on the natural life loss and action life loss of the power station, and is related to the overall output power P of the power station. total And functions related to the number of days t used.

[0092] Specifically, the power station energy consumption f loss The expression is:

[0093] f loss (P i )=C B +C PCS +C air =α i P i +β i P i +γP total

[0094] α i The expression is:

[0095]

[0096] βi The expression is:

[0097]

[0098] The expression of γ is:

[0099]

[0100] Where, α i Indicates the energy efficiency correction value of the i-th battery group in the output battery group; represents the energy efficiency level of the i-th battery pack; It represents the correction amount of the energy efficiency of the i-th battery pack affected by the SOC, and its segmented value is obtained from the actual characteristics and measurement values ​​of the battery pack; represents the operating voltage / open circuit voltage across the i-th battery pack; P i Indicates the output power of the i-th battery pack; SOC i represents the state of charge (SOC) of the i-th battery pack.

[0101] β i represents the energy efficiency correction of the j-th PCS; It represents the correction amount of the j-th PCS affected by the output power; It represents the energy efficiency level of the jth PCS. Its value can be directly obtained from the technical specification or calculated according to the above formula; Respectively represent the DC side / AC side power values ​​of the j-th PCS.

[0102] γ represents the energy efficiency correction of electrical equipment in the station.

[0103] (2) Constraints: satisfy the power instruction P target , the output power P of each output battery group and the state of charge SOC of each output battery group. The expressions are as follows:

[0104]

[0105] Where, P max-c，i / P min-c，i Indicates the maximum / minimum charging power of the i-th battery pack in the output battery pack; P max-d，i / P min-c，i Indicates the maximum / minimum discharge power of the i-th battery pack; represents the minimum / maximum constraint value of the state of charge (SOC) of the i-th battery pack; D represents the number of output battery packs.

[0106] It will be easily understood by those skilled in the art that the above description is merely a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A power allocation strategy for optimizing energy consumption in energy storage power stations, characterized in that: The steps include: (1) According to the command power obtained and the health status of each battery pack in the current target energy storage power station and state of charge , determine the output battery pack; the command power This is the dispatching command power issued by the power grid or the power that the target energy storage power station needs to provide under active support; (2) The state of charge of each output battery pack Input into the pre-established objective function that includes constraints and can optimize multiple objectives at the same time to obtain the output power of each output battery group And the output power of each output battery pack Assigned to the corresponding output battery group; wherein, the multiple objectives include minimum power station energy consumption, best power station economy and longest power station life; the constraint conditions include the command power Constraints, output power of each output battery group Constraints and state of charge of each output battery pack Constraints; the expression of the objective function is: Where, / / represents a weight coefficient, and the weight coefficient is assigned by the hierarchical analysis method; Indicates the energy consumption of the power station, based on the energy consumption of the battery pack , PCS energy consumption , Energy consumption of electrical equipment in the station The energy efficiency level under different operating conditions is established in relation to the overall output power of the power station. , the output power of each battery pack in the output battery pack Related functions; The economic efficiency of the power station is established based on the initial construction cost, operation cost and external service income of the power station, which is related to the overall output power of the power station. , service mileage and number of days used Related functions; Indicates the life of the power station, which is established based on the natural life loss and action life loss of the power station, and is related to the overall output power of the power station. and number of days used Related functions.

2. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 1, characterized in that: Step (1) specifically includes: (1) According to the command power The rated power of the target energy storage power station , determine the number n of battery packs required to operate in the target energy storage power station; (2) According to the health status of each battery pack Determine the abnormal battery groups and their number in the target energy storage power station, and determine the number m of workable battery groups in the target energy storage power station based on the abnormal battery groups and their number; (3) When the number m of the workable battery packs is greater than or equal to the required number n of battery packs, select the battery packs that are under the current command power. The top n battery packs in the charge / discharge efficiency ranking are the output battery packs; otherwise, all the workable battery packs are the output battery packs.

3. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 2, characterized in that: The expression for the number of battery packs required to run in step (1) n=f(N) is: Where, is the total number of battery packs in the target energy storage power station; [·] represents a rounding function, the value is the largest integer not greater than "·"; when When is an integer multiple of 4, is 0, otherwise is 1.

4. The power allocation strategy for optimizing energy consumption of an energy storage power station according to claim 2 or 3, characterized in that: In step (3), when the number m of operable battery packs is greater than or equal to the required number n of battery packs, the steps for determining the output battery pack are specifically as follows: When the command power When the value is negative, the state of charge of the working battery pack is prioritized. The battery pack with a charge level between 20% and 60% is used as the output battery pack. When the number of battery packs between 20% and 60% is less than the required number of battery packs n, the state of charge is preferentially selected from the working battery packs. The battery pack with less than 20% capacity is used as the output battery pack; When the command power When the value is positive, the state of charge of the working battery pack is prioritized. The battery pack with a charge level between 40% and 80% is used as the output battery pack. When the number of battery packs between 40% and 80% is less than the required number of battery packs n, the state of charge is preferentially selected from the working battery packs. Battery packs with a capacity above 80% are used as output battery packs.

5. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 4 is characterized in that: The expression for selecting the output battery group from the workable battery groups is: Where, is the state of charge SOC of the kth battery pack in the working battery pack, when the command power When it is a positive value, the output battery group is selected in the order of partition number 4, 5, 3, 6, and 2; when the command power is a negative value, the output battery group is selected in the order of partition number 3, 2, 4, 1, and 5, and the battery groups in the same partition number are selected in the order of | |Select the value from small to large.

6. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 1, characterized in that: The power station energy consumption The expression is: The expression is: The expression is: The expression is: Where, represents the energy efficiency correction value of the i-th battery group in the output battery group; represents the energy efficiency level of the i-th battery pack; represents the correction amount of the energy efficiency of the i-th battery pack affected by the SOC, and its segmented values ​​are obtained based on the actual characteristics and measurement values ​​of the battery pack; / represents the operating voltage / open circuit voltage across the i-th battery pack; is the ratio of the operating voltage to the open circuit voltage across the i-th battery pack; is the ratio of the open circuit voltage and the operating voltage across the i-th battery pack; represents the output power of the i-th battery pack; Indicates the state of charge of the i-th battery pack ; represents the energy efficiency correction of the i-th PCS; It represents the correction amount of the i-th PCS affected by the output power; represents the energy efficiency level of the i-th PCS; / Indicates the DC side / AC side power value of the i-th PCS; is the ratio of the DC side power value to the AC side power value of the i-th PCS; is the ratio of the AC side power value to the DC side power value of the i-th PCS; Indicates the energy efficiency correction value of electrical equipment in the station.

7. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 1, characterized in that: The economic performance of the power station The expression is: Where, Indicates the total investment in power station construction; Indicates the expected life of the power station; is the power plant action cost function; represents the external service revenue function.

8. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 1, characterized in that: The life of the power station The expression is: Where, A function that represents the natural aging of the battery over time; Indicates running the depreciated life function.

9. The power allocation strategy for optimizing energy consumption of energy storage power stations according to claim 1, characterized in that: The constraint condition is expressed as: Where, / Indicates the maximum / minimum charging power of the i-th battery pack in the output battery pack; / Indicates the maximum / minimum discharge power of the i-th battery pack; / represents the minimum / maximum constraint value of the state of charge (SOC) of the i-th battery pack; and D represents the number of output battery packs.

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