Method and device for determining battery performance of energy storage system, computer equipment and medium

Abstract

The invention relates to an energy storage system battery performance determination method and device, computer equipment, a storage medium and a computer program product. The method comprises the steps of obtaining a parameter value of a first performance index collected by an energy storage system at a current moment; the parameter values of the first performance indexes are processed according to a preset performance index fitting processing relation, parameter values of second performance indexes are obtained, and the preset performance index fitting processing relation is obtained based on fitting of the at least one first performance index; and determining a battery performance parameter value of the energy storage system based on the parameter range of the preset performance index and the parameter value of the second performance index. According to the whole scheme, the parameter value of the first performance index of the battery of the energy storage system is collected in real time, the parameter value of the second performance index is calculated in real time, and then the accurate battery performance parameter value of the energy storage system is obtained according to the parameter range of the preset performance index and the parameter value of the second performance index. And the real-time calculation requirement of the energy storage system battery can be met.

Description

Technical Field

[0001] The present application relates to the field of battery technology, and in particular to a method, device, computer equipment, storage medium and computer program product for determining battery performance of an energy storage system. Background Art

[0002] Lithium batteries have a wide range of application prospects in the field of energy storage devices due to their excellent operating performance. For example, they can be well applied to high-voltage and large-capacity energy storage systems. High-voltage and large-capacity energy storage systems are composed of multiple energy storage submodules containing batteries in cascade, and the battery instability increases. Therefore, it is very necessary to establish a battery performance evaluation method for energy storage systems from the perspective of short-term and long-term performance.

[0003] At present, the evaluation of submodule batteries in high-voltage and large-capacity energy storage systems is mainly based on SOC (State of Charge) estimation, which cannot accurately evaluate the performance of batteries. Therefore, there is an urgent need for a method that can accurately evaluate the performance of batteries in energy storage systems. Summary of the invention

[0004] Based on this, it is necessary to provide an accurate method, device, computer equipment, computer-readable storage medium and computer program product for determining battery performance of an energy storage system in response to the above technical problems.

[0005] In a first aspect, the present application provides a method for determining battery performance of an energy storage system. The method comprises:

[0006] Obtaining a parameter value of a first performance indicator collected by the energy storage system at the current moment;

[0007] Processing the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators;

[0008] Based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, a battery performance parameter value of the energy storage system is determined.

[0009] In the above embodiment, the parameter value of the first performance indicator of the battery of the energy storage system is collected in real time, and then the parameter value of the first performance indicator is processed according to the preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator that can accurately characterize the performance of the battery of the energy storage system, and then the accurate battery performance parameter value of the energy storage system is obtained according to the parameter range of the preset performance indicator and the parameter value of the second performance indicator, and the real-time calculation requirements of the battery of the energy storage system can be met.

[0010] In one embodiment, the first performance indicator includes current, voltage, and temperature; the second performance indicator includes battery state of charge, battery health status, battery power capability, and current inconsistency;

[0011] The step of processing the parameter value of the first performance indicator according to the preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator includes at least one of the following:

[0012] Based on the fitting processing relationship between the voltage and the battery state of charge, the voltage in the parameter value of the first performance indicator is processed to obtain the parameter value of the battery state of charge;

[0013] Based on the fitting processing relationship between the current, the temperature and the battery power capability, the current and the temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery power capability;

[0014] Based on the fitting processing relationship between voltage, temperature and battery health state, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery health state;

[0015] Based on the fitting processing relationship between the current and the current inconsistency, the current in the parameter value of the first performance indicator is processed to obtain the parameter value of the current inconsistency.

[0016] In the above embodiments, in the application scenario of high-voltage and large-capacity energy storage systems, not only the inconsistency problem caused by multiple batteries and multiple parallel energy storage units is considered, but also the high-frequency real-time control method of high-voltage and large-capacity energy storage systems can be coordinated, thereby improving the reliability and energy utilization efficiency of the energy storage system and extending the service life of the energy storage system. It is no longer necessary to perform offline charge and discharge tests to obtain the second performance index of the operating battery. The parameter value of the first performance index can be obtained through real-time sampling, and the parameter value of the second performance index can be obtained through calculation through the pre-established fitting processing relationship of each second performance index. After being fused with the second performance index, the battery performance parameter value of the energy storage system is obtained, thereby achieving rapid dynamic evaluation of battery performance and meeting the requirements of real-time response of system control.

[0017] In one embodiment, determining the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes:

[0018] Determining the operating condition type of the energy storage system;

[0019] Determining a calculated value of a second performance indicator under the current operating condition according to the operating condition type;

[0020] Based on the parameter range of the preset performance indicator and the calculated value of the second performance indicator under the current working condition, the battery performance parameter value of the energy storage system is determined.

[0021] In the above embodiment, the calculated value of the second performance indicator under the current operating condition is determined based on the operating condition of the energy storage system. The battery performance parameter value of the energy storage system determined in combination with the operating condition can more accurately reflect the battery performance of multiple sub-modules of the energy storage system, and thus can accurately determine the sub-module that is suitable for use at the current moment.

[0022] In one embodiment, determining the calculated value of the second performance indicator under the current operating condition according to the operating condition type includes:

[0023] When the operating condition type is a discharging operating condition, determining the parameter value of the battery state of charge as the parameter value of the battery state of charge under the current operating condition;

[0024] When the operating condition type is a charging operating condition, the difference between a preset battery state of charge maximum value and a parameter value of the battery state of charge is determined as the parameter value of the battery state of charge under the current operating condition.

[0025] In the above embodiment, the parameter value of the battery state of charge under the current working condition is determined based on the charging and discharging working condition of the energy storage system, and then the battery performance parameter value of the energy storage system obtained by fusion calculation can more accurately reflect the battery performance of multiple sub-modules of the energy storage system under different working conditions, and the sub-module suitable for use at the current moment can be accurately determined for different working conditions.

[0026] In one of the embodiments, the parameter range of the preset performance indicator includes the parameter range of the second performance indicator;

[0027] The determining of the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes:

[0028] Determining a discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator;

[0029] A weighted calculation is performed based on the parameter value of the discretized second performance indicator to obtain a battery performance parameter value of the energy storage system.

[0030] In the above embodiment, by discretizing the parameter value of the second performance indicator, the scoring result of each performance indicator of the battery can be more intuitively reflected, and then the battery performance parameter value of each submodule of the energy storage system obtained by weighted calculation based on the discretized parameter value of the second performance indicator can more intuitively reflect the state of the battery, and then the submodule suitable for use at the current moment can be quickly determined.

[0031] In one embodiment, the parameter range of the second performance indicator includes a safe operating range of the second performance indicator and an optimal operating range of the second performance indicator;

[0032] Determining the discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator includes:

[0033] Determining an intermediate parameter value of the second performance indicator according to a relationship between the parameter value of the second performance indicator and the safe operating range of the second performance indicator;

[0034] A discretized parameter value of the second performance indicator is determined according to the optimal operating range of the second performance indicator and an intermediate parameter value of the second performance indicator.

[0035] In the above embodiment, the parameter value of the second performance indicator of the submodule within the safe operating range is screened by considering the safe operating range of the second performance indicator, and then the discretized parameter value of the second performance indicator is determined in combination with the optimal operating range of the second performance indicator. Then, the battery performance parameter value of each submodule of the energy storage system obtained by weighted calculation based on the parameter value of the discretized second performance indicator can more intuitively reflect the state of the battery, and thus the submodule suitable for use at the current moment can be quickly and safely determined.

[0036] In one embodiment, the weighted calculation based on the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of the energy storage system includes:

[0037] A weighted calculation is performed based on a preset weight coefficient of the second performance indicator and the parameter value of the discretized second performance indicator to obtain a battery performance parameter value of the energy storage system.

[0038] In the above embodiment, the battery performance parameter value of each submodule of the energy storage system is calculated based on the weight coefficient of the preset second performance indicator, so that a more accurate battery performance parameter value of the energy storage system can be obtained.

[0039] In one embodiment, the method for determining the weight coefficient of the preset second performance indicator includes:

[0040] Acquire initial weight coefficients of a plurality of second performance indicators, wherein the initial weight coefficients are obtained based on a weight allocation rule;

[0041] A discreteness check is performed on the plurality of the initial weight coefficients, and when the initial weight coefficients pass the discreteness check, a plurality of weight coefficients of the second performance indicators are obtained.

[0042] In the above embodiment, by performing a discreteness check on the initial weight coefficient, a more accurate and reasonable weight coefficient of the second performance indicator can be obtained, and then the battery performance parameter value calculated based on the accurate weight coefficient can more accurately reflect the battery status, and thus the sub-module suitable for use at the current moment can be accurately determined.

[0043] In one embodiment, the parameter range of the preset performance indicator includes the parameter range of the first performance indicator and the parameter range of the second performance indicator;

[0044] The determining of the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes:

[0045] Determining an intermediate parameter value of the second performance indicator according to a relationship between the first performance indicator and the parameter range of the first performance indicator, and a relationship between the second performance indicator and the parameter range of the second performance indicator;

[0046] A parameter value of the battery state of charge is extracted from the intermediate parameter value for determining the second performance indicator, and a battery performance parameter value of the energy storage system is determined according to the parameter value of the battery state of charge.

[0047] In the above embodiment, since the battery state of charge has a great influence on the battery performance, in the scenario where the battery performance calculation accuracy is not high but the efficiency is high, the performance indicator parameter values ​​within the safe range are first screened according to the safe operating range of the first performance indicator and the second performance indicator. Then, when the parameter values ​​of all performance indicators of each submodule are within the safe operating range, the parameter value of the battery state of charge is directly used as the battery performance parameter value of the submodule. The battery performance of each submodule of the energy storage system can be quickly and safely determined, and the submodule that is suitable for use at the current moment can be quickly determined.

[0048] In one embodiment, before determining the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the method further includes:

[0049] Obtaining a parameter value of a battery health state of each battery in a submodule of an energy storage system, and determining a parameter value of a minimum battery health state in a submodule of the energy storage system;

[0050] The parameter value of the minimum battery health state is determined as the parameter value of the battery health state of the submodule in the energy storage system.

[0051] In the above embodiment, the battery health status parameter values ​​of multiple batteries in the sub-module of the comprehensive energy storage system are used to determine the battery health status of the sub-module, which can more accurately reflect the battery performance of each sub-module of the energy storage system, and further accurately determine the sub-module that is suitable for use at the current moment.

[0052] In one embodiment, the method further comprises:

[0053] Obtaining the parameter value of the battery state of charge of each battery in the submodule of the energy storage system;

[0054] When the operating condition type is a discharge operating condition, determining the parameter value of the lowest battery state of charge in the submodule of the energy storage system as the parameter value of the battery state of charge of the submodule of the energy storage system;

[0055] When the operating condition type is a charging operating condition, the parameter value of the highest battery state of charge in the submodules in the energy storage system is determined as the parameter value of the battery state of charge of the submodules in the energy storage system.

[0056] In the above embodiment, the battery state of charge of the submodule is determined by integrating the battery state of charge parameter values ​​of multiple batteries in the submodule of the comprehensive energy storage system and the charging and discharging conditions, which can more accurately reflect the battery performance of each submodule of the energy storage system. The submodule that is suitable for use at the current moment can be accurately determined for different working conditions.

[0057] In one embodiment, the method further comprises:

[0058] Determine the battery performance parameter value of each submodule of the energy storage system;

[0059] Based on the battery performance parameter value of each submodule, the submodule with the highest battery performance parameter value is determined, and the submodule with the highest battery performance parameter value is determined as the target submodule.

[0060] In the above embodiment, the battery performance parameter value of each submodule of the energy storage system is integrated to determine the submodule that is most suitable for use at the current moment, so that an accurate target submodule can be obtained.

[0061] In a second aspect, the present application also provides a device for determining battery performance of an energy storage system. The device comprises:

[0062] An acquisition module, used to acquire a parameter value of a first performance indicator collected by the energy storage system at a current moment;

[0063] a processing module, configured to process the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators;

[0064] A determination module is used to determine the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator.

[0065] In a third aspect, the present application further provides a computer device. The computer device includes a memory and a processor, the memory stores a computer program, and the processor implements the following steps when executing the computer program:

[0066] Obtaining a parameter value of a first performance indicator collected by the energy storage system at the current moment;

[0067] Processing the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators;

[0068] Based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, a battery performance parameter value of the energy storage system is determined.

[0069] In a fourth aspect, the present application further provides a computer-readable storage medium. The computer-readable storage medium stores a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0070] Obtaining a parameter value of a first performance indicator collected by the energy storage system at the current moment;

[0071] Processing the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators;

[0072] Based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, a battery performance parameter value of the energy storage system is determined.

[0073] In a fifth aspect, the present application further provides a computer program product. The computer program product includes a computer program, and when the computer program is executed by a processor, the following steps are implemented:

[0074] Obtaining a parameter value of a first performance indicator collected by the energy storage system at the current moment;

[0075] Processing the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators;

[0076] Based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, a battery performance parameter value of the energy storage system is determined.

[0077] The above-mentioned energy storage system battery performance determination method, device, computer equipment, storage medium and computer program product obtain the parameter value of the first performance indicator collected by the energy storage system at the current moment; process the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator, and the preset performance indicator fitting processing relationship is obtained based on at least one of the first performance indicators; determine the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator. The entire scheme collects the parameter value of the first performance indicator of the energy storage system battery in real time, and then processes the parameter value of the first performance indicator according to the preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator that can accurately characterize the performance of the energy storage system battery, and then obtains the accurate battery performance parameter value of the energy storage system according to the parameter range of the preset performance indicator and the parameter value of the second performance indicator, and can meet the real-time calculation requirements of the energy storage system battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0078] In order to more clearly illustrate the technical solutions in the embodiments of the present application or the conventional technology, the drawings required for use in the embodiments or the conventional technology descriptions are briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative work.

[0079] Figure 1 An application environment diagram of a method for determining battery performance of an energy storage system in one embodiment;

[0080] Figure 2 A schematic diagram of a flow chart of a method for determining battery performance of an energy storage system in one embodiment;

[0081] Figure 3 A schematic flow chart of a method for determining battery performance of an energy storage system in another embodiment;

[0082] Figure 4 A schematic flow chart of a method for determining battery performance of an energy storage system in yet another embodiment;

[0083] Figure 5 A schematic diagram of a flow chart of a method for determining battery performance of an energy storage system in an application embodiment;

[0084] Figure 6 A schematic diagram of a flow chart of a method for determining battery performance of an energy storage system in another embodiment;

[0085] Figure 7 It is a structural block diagram of a method and device for determining battery performance of an energy storage system in one embodiment;

[0086] Figure 8 FIG. 4 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0087] In order to make the purpose, technical solution and advantages of the present application more clearly understood, the present application is further described in detail below in conjunction with the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain the present application and are not used to limit the present application.

[0088] Due to their excellent operating performance, lithium batteries have broad application prospects in the field of energy storage devices. For example, they can be well applied to high-voltage and large-capacity energy storage systems. High-voltage and large-capacity energy storage systems are composed of multiple cascaded energy storage submodules containing batteries. Compared with the scenario of traditional automotive power batteries, the number of batteries in series and parallel has increased significantly, and the impact of inconsistency between batteries on battery pack performance and energy storage system operation has also increased. In addition, battery performance is also affected by factors such as temperature, port voltage, and degree of aging. Therefore, it is very necessary to establish a multi-angle battery performance evaluation method from the perspective of short-term and long-term performance, so that the energy storage system can select suitable energy storage submodules for use, thereby improving the energy utilization and reliability of the energy storage system and extending the system's operating life.

[0089] At present, the evaluation of submodule batteries in high-voltage and large-capacity energy storage systems is mainly based on SOC estimation. When the energy storage system is discharging, submodules with high battery SOC are prioritized, and when charging, submodules with low battery SOC are prioritized. This method only considers a single aspect of the battery's characteristics, is one-sided, and cannot comprehensively evaluate the battery's performance. Other battery comprehensive performance evaluation methods are targeted at traditional automotive power batteries, and their selection of indicators and real-time calculations cannot meet the control requirements of high-voltage and large-capacity energy storage systems.

[0090] In order to solve the problem that the real-time performance of the current battery evaluation method cannot meet the control requirements of the high-voltage and large-capacity energy storage system, and the current analysis method cannot accurately and comprehensively evaluate the battery performance of the energy storage system, this application comprehensively considers the short-term and long-term performance factors of the energy storage system to comprehensively evaluate the operating performance of the sub-module batteries of the energy storage system in real time. This application obtains the parameter value of the first performance indicator collected by the energy storage system at the current moment; processes the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator, and the preset performance indicator fitting processing relationship is obtained based on the fitting of at least one first performance indicator; based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the battery performance parameter value of the energy storage system is determined.

[0091] The method for determining the battery performance of an energy storage system provided in the embodiment of the present application can be applied to Figure 1 In the application environment shown, the terminal 102 communicates with the server 104 through a network. The data storage system can store data that the server 104 needs to process. The data storage system can be integrated on the server 104, or placed on the cloud or other network servers.

[0092] In one possible implementation, the terminal 102 obtains the parameter value of the first performance indicator collected by the energy storage system at the current moment; processes the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator, the preset performance indicator fitting processing relationship is obtained based on at least one first performance indicator fitting, and the preset performance indicator fitting processing relationship is stored in the server 104; based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the battery performance parameter value of the energy storage system is determined.

[0093] In another possible implementation, the server 104 obtains the parameter value of the first performance indicator collected by the energy storage system at the current moment; processes the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on the fitting of at least one first performance indicator; and determines the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator.

[0094] The terminal 104 may be, but is not limited to, various personal computers, laptops, smart phones, tablet computers, IoT devices, and IoT devices may be smart TVs, smart car devices, etc. The server 106 may be implemented as an independent server or a server cluster consisting of multiple servers.

[0095] The method for determining the battery performance of an energy storage system provided in the present application can be applied to the application scenario of a high-voltage and large-capacity energy storage system, and is applicable to any energy storage system composed of cascaded energy storage submodules, including but not limited to MMC (modular multilevel converter) type energy storage valves, DC direct-mounted energy storage valves, and AC direct-mounted energy storage valves.

[0096] In some embodiments, Figure 2 As shown, a method for determining battery performance of an energy storage system is provided, and the method is applied to Figure 1 The terminal 102 in the example is used as an example to illustrate, and the following steps are included:

[0097] Step 200: Obtain the parameter value of the first performance indicator collected by the energy storage system at the current moment.

[0098] The energy storage system includes but is not limited to MMC energy storage converter valves, DC direct-mounted energy storage valves, and AC direct-mounted energy storage valves, etc. The first performance indicator is a performance description parameter of the battery in the energy storage system submodule, which can be collected online in real time.

[0099] In some embodiments, the terminal obtains an energy storage system battery performance determination instruction, and obtains a parameter value of a first performance indicator collected by the energy storage system at the current moment according to the energy storage system battery performance determination instruction. The terminal can also obtain the parameter value of the first performance indicator collected by the energy storage system at the current moment according to a preset sampling frequency. The preset sampling frequency can be stored locally in the terminal or in a remote server, and the preset sampling frequency is set by the staff according to the real-time control requirements of the specific application scenario, including but not limited to 50us (microseconds).

[0100] Step 400: Process the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator.

[0101] The preset performance indicator fitting processing relationship is a fitting function of the second performance indicator, and the preset performance indicator fitting processing relationship is obtained based on the fitting of at least one first performance indicator. The second performance indicator is a real-time online calculation parameter of the battery performance of the energy storage system submodule.

[0102] In some embodiments, the terminal obtains a preset performance indicator fitting processing relationship from a local or remote server, determines the preset performance indicator fitting processing relationship corresponding to each second performance indicator, and the parameter value of the first performance indicator corresponding to the preset performance indicator fitting processing relationship, processes the parameter value of the corresponding first performance indicator based on the preset performance indicator fitting processing relationship corresponding to each second performance indicator, and obtains the parameter value of each second performance indicator.

[0103] Step 600, determining a battery performance parameter value of the energy storage system based on a parameter range of a preset performance indicator and a parameter value of a second performance indicator.

[0104] In some embodiments, the terminal corrects the parameter value of the second performance indicator based on the parameter range of the preset performance indicator to obtain the corrected parameter value of the second performance indicator, and then fuses the corrected parameter value of the second performance indicator to obtain the battery performance parameter value of the energy storage system. Optionally, the parameter value of the corrected second performance indicator of each submodule of the energy storage system is fused to obtain the battery performance parameter value of each submodule of the energy storage system.

[0105] The above-mentioned method for determining the battery performance of the energy storage system obtains the parameter value of the first performance indicator collected by the energy storage system at the current moment; processes the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator, and the preset performance indicator fitting processing relationship is obtained based on the fitting of at least one first performance indicator; and determines the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator. The entire scheme collects the parameter value of the first performance indicator of the battery of the energy storage system in real time, and then processes the parameter value of the first performance indicator according to the preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator that can accurately characterize the battery performance of the energy storage system, and then obtains the accurate battery performance parameter value of the energy storage system according to the parameter range of the preset performance indicator and the parameter value of the second performance indicator, and can meet the real-time calculation requirements of the battery of the energy storage system.

[0106] In some optional embodiments, the first performance indicator includes current, voltage, and temperature; the second performance indicator includes battery state of charge, battery health state, battery power capability, and current inconsistency;

[0107] Processing the parameter value of the first performance indicator according to the performance indicator fitting model to obtain the parameter value of the second performance indicator includes at least one of the following:

[0108] Based on the fitting processing relationship between the voltage and the battery state of charge, the voltage in the parameter value of the first performance indicator is processed to obtain the parameter value of the battery state of charge;

[0109] Based on the fitting processing relationship between the current, the temperature and the battery power capability, the current and the temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery power capability;

[0110] Based on the fitting processing relationship between voltage, temperature and battery health state, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery health state;

[0111] Based on the fitting processing relationship between the current and the current inconsistency, the current in the parameter value of the first performance indicator is processed to obtain the parameter value of the current inconsistency.

[0112] In some embodiments, a plurality of performance indicators of long-term factors and short-term factors that affect battery performance are comprehensively considered to comprehensively evaluate the battery performance of the energy storage system. The first performance indicator is an indicator that can be collected in real time and directly reflects the battery status. The first performance indicator may include current, voltage, and temperature, and can be collected in real time based on a sensor corresponding to the first performance indicator to obtain a parameter value of the first performance indicator.

[0113] The second performance indicator is an indicator that can be calculated in real time based on the parameter value of the first performance indicator. The second performance indicator may include the battery state of charge (SOC), battery state of health (SOH), battery power capability, and current inconsistency. The preset performance indicator fitting processing relationship is obtained based on the electrical test of the sample battery pack. The sample battery pack is a battery pack for testing. The electrical test includes but is not limited to battery capacity test, hybrid pulse capability test, small rate charge and discharge test, high and low temperature charge and discharge test, etc. First, based on the electrical test, the basic characteristic parameters of each battery in the sample battery pack are obtained. The basic characteristic parameters include but are not limited to charge and discharge voltage, battery capacity, battery power, battery internal resistance, remaining number of cycles, battery temperature, current rate, parallel battery branch circulation, etc., and at least one first performance indicator is determined based on the basic characteristic parameters as a performance indicator that has a greater impact on the second performance indicator. The second performance indicator is modeled based on the determined first performance indicator to obtain the preset performance indicator fitting processing relationship.

[0114] After electrical testing, it was found that since there is a corresponding relationship between the battery SOC and the voltage, the fitting processing relationship of the battery state of charge is established based on the voltage. The battery power capacity is affected by the battery temperature and the battery current, and there is a corresponding relationship, so the fitting processing relationship between the battery power capacity and the battery temperature and the battery current can be established through testing. The battery health state is affected by the battery temperature and the battery current, and there is a corresponding relationship, so the fitting processing relationship between the battery health state and the battery temperature and the battery current can be established through testing. Current inconsistency is affected by the current of each battery in the submodule, and a fitting processing relationship of current inconsistency is established based on the current. Fitting methods include but are not limited to linear fitting, exponential fitting, logarithmic fitting, etc.

[0115] Based on the current, voltage and battery temperature collected in real time, the voltage in the parameter value of the first performance indicator can be processed based on the fitting processing relationship between the voltage and the battery state of charge to obtain the parameter value of the battery state of charge; based on the fitting processing relationship between the current, temperature and the battery power capability, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery power capability; based on the fitting processing relationship between the voltage, temperature and the battery health state, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery health state; based on the fitting processing relationship between the current and the current inconsistency, the current in the parameter value of the first performance indicator is processed to obtain the parameter value of the current inconsistency.

[0116] Furthermore, the first performance indicator corresponding to the preset performance indicator fitting processing relationship is not limited to the examples provided in the above embodiments. For example, in an application embodiment, the preset performance indicator fitting processing relationship between the battery state of charge and the current can be obtained based on the traditional ampere-hour integration method. The preset performance indicator fitting processing relationship can be:

[0117]

[0118] Among them, S SOC (t) is the estimated SOC value of the battery at time t, γ is the battery self-discharge coefficient, Δt is the sampling time scale, η is the battery charge and discharge efficiency, I(t) is the current flowing through the battery at time t, and Q0 is the nominal capacity of the battery.

[0119] When establishing the fitting processing relationship of battery power capability, the battery power is taken as the dependent variable, the battery temperature and the battery SOC are taken as the independent variables, and the multivariate nonlinear regression fitting model of battery power capability is established:

[0120] y(P)=k1+k2×x r +k3×x SOC +k4×x T 2 +k5×x SOC 2 +k6×x T × SOC

[0121] Among them, k1....k6 are constant coefficients, x T is the battery temperature, x SOC is the battery SOC, and y(P) is the battery power capability.

[0122] The battery power value was obtained by performing multiple tests under the following conditions.

[0123] Table 1 Battery power capability test conditions

[0124] SOC(%) 20 20 20 20 50 50 50 50 Temperature(℃) -10 10 25 40 -10 10 25 40 SOC(%) 80 80 80 80 5 5 5 5 Temperature(℃) -10 10 25 40 -10 10 25 40

[0125] The coefficients of the model are fitted according to the experimental data, and the credibility is tested. If the credibility does not meet the requirements, the battery is tested again until the fitting processing relationship of the battery power capacity obtained by fitting meets the credibility.

[0126] When establishing the fitting processing relationship of battery power capability, taking the method of characterizing SOH by cycle number as an example, multiple batteries with cycle numbers of 0, 200, 400, 600, 800, and 1000 are selected for charge and discharge experiments. (Assuming that the battery cycle life is 1000 times, that is, batteries with SOH of 100%, 80%, 60%, 40%, 20%, and 0% participate in the experiment).

[0127] Multiple constant current full charge and full discharge experiments were performed on batteries with different SOHs to obtain multiple sets of data on the battery port voltage, battery SOC, and battery temperature under different SOHs. The battery SOH was used as the dependent variable, and the battery temperature, battery port voltage, and battery SOC were used as independent variables to establish a multivariate nonlinear regression fitting model:

[0128] y(SOH)=k1+k2×xV+k3×x SOC +k4×x T +k4×x V 2 +k5×x SOC 2 +k4×x T 2 +k6×xV×x SOC × T

[0129] Among them, k1...k6 are constant coefficients, x V is the battery terminal voltage, x SOC is the battery SOC, x T is the battery temperature, and y(SOH) is the battery SOH.

[0130] When establishing the fitting processing relationship of current inconsistency, in the series-parallel battery pack, sampling is implemented to obtain the current of each battery, and the current is sorted according to the size. ΔI represents the difference between the maximum current and the minimum current. Indicates the average current of the battery pack, Characterizes the current inconsistency of the battery pack.

[0131] In the above embodiments, in the application scenario of high-voltage and large-capacity energy storage systems, not only the inconsistency problem caused by multiple batteries and multiple parallel energy storage units is considered, but also the high-frequency real-time control method of high-voltage and large-capacity energy storage systems can be coordinated, thereby improving the reliability and energy utilization efficiency of the energy storage system and extending the service life of the energy storage system. It is no longer necessary to perform offline charge and discharge tests to obtain the second performance index of the operating battery. The parameter value of the first performance index can be obtained through real-time sampling, and the parameter value of the second performance index can be obtained through calculation through the pre-established fitting processing relationship of each second performance index. After being fused with the second performance index, the battery performance parameter value of the energy storage system is obtained, thereby achieving rapid dynamic evaluation of battery performance and meeting the requirements of real-time response of system control.

[0132] In some optional embodiments, such as Figure 3 As shown, based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the battery performance parameter value of the energy storage system is determined, including:

[0133] Step 620, determining the operating condition type of the energy storage system.

[0134] Step 640: Determine the calculated value of the second performance indicator under the current operating condition according to the operating condition type.

[0135] Step 660, determining a battery performance parameter value of the energy storage system based on a parameter range of a preset performance indicator and a calculated value of a second performance indicator under current operating conditions.

[0136] The operating condition types of the energy storage system include charging conditions and discharging conditions. The calculated value of the second performance indicator under the current operating condition is the calculated value of the second performance indicator involved in the subsequent weighted calculation.

[0137] In some embodiments, the terminal corrects the parameter value of the second performance indicator of the submodule of the energy storage system based on the parameter range of the preset performance indicator to obtain the corrected parameter value of the second performance indicator of the submodule of the energy storage system. Then, the terminal determines the operating condition type of the energy storage system, and determines the calculated value of the second performance indicator of the submodule of the energy storage system under the current operating condition according to the operating condition type and the corrected parameter value of the second performance indicator of the submodule of the energy storage system. Then, the calculated values ​​of the second performance indicators of the submodule of the energy storage system under the current operating condition are merged to obtain the battery performance parameter value of the energy storage system.

[0138] In the above embodiment, the calculated value of the second performance indicator under the current operating condition is determined based on the operating condition of the energy storage system. The battery performance parameter value of the energy storage system determined in combination with the operating condition can more accurately reflect the battery performance of multiple sub-modules of the energy storage system, and thus can accurately determine the sub-module that is suitable for use at the current moment.

[0139] In some optional embodiments, such as Figure 4 As shown, according to the operating condition type, determining the calculated value of the second performance indicator under the current operating condition includes:

[0140] Step 642, when the operating condition type is a discharging operating condition, determining the parameter value of the battery state of charge as a calculated value of the battery state of charge under the current operating condition;

[0141] Step 644, when the operating condition type is a charging operating condition, the difference between the preset battery state of charge maximum value and the parameter value of the battery state of charge is determined as the calculated value of the battery state of charge under the current operating condition.

[0142] In some embodiments, since the charge and discharge state of the battery will affect the calculation of the battery state of charge, and thus affect the calculation of the battery performance of the energy storage system, the operating condition type of the battery is comprehensively considered to determine the calculated value of the battery state of charge under the current operating condition. When the operating condition type is a discharge condition, the parameter value of the battery state of charge is determined as the calculated value of the battery state of charge under the current operating condition; when the operating condition type is a charging condition, the calculated value of the battery state of charge under the current operating condition is obtained based on the difference between the preset maximum value of the battery state of charge and the parameter value of the battery state of charge. The preset maximum value of the battery state of charge is the score corresponding to the maximum value of the battery state of charge. For example, the preset maximum value of the battery state of charge can be 100, which can be set according to the actual parameters of the battery of the energy storage system submodule.

[0143] In the above embodiment, the calculated value of the battery state of charge under the current working condition is determined based on the charging and discharging working condition of the energy storage system, and then the battery performance calculated value of the energy storage system obtained by fusion calculation can more accurately reflect the battery performance of multiple sub-modules of the energy storage system under different working conditions, and thus can accurately determine the sub-module suitable for use at the current moment.

[0144] In some optional embodiments, determining a battery performance parameter value of the energy storage system based on a parameter range of a preset performance indicator and a parameter value of a second performance indicator includes:

[0145] Determining a discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator;

[0146] A weighted calculation is performed based on the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of the energy storage system.

[0147] The parameter range of the preset performance indicator includes the parameter range of the second performance indicator. The parameter range of the second performance indicator includes the upper and lower limits of the second performance indicator. The parameter range of the preset performance indicator is also obtained through electrical testing.

[0148] In some embodiments, based on the parameter range of the second performance indicator, the parameter values ​​within the parameter range are discretized to obtain a score value for each parameter value. Then, based on the parameter value of the second performance indicator obtained by fitting, the discretized score value corresponding to the parameter value is determined. Then, a weighted calculation is performed based on the discretized parameter value of the second performance indicator to obtain the battery performance parameter value of the energy storage system. Discretization methods include but are not limited to linear methods, logarithmic methods, and fitting approximation methods, which can be selected according to actual engineering requirements.

[0149] Furthermore, based on the parameter range of the second performance indicator, the parameter values ​​within the parameter range are converted into percentages to obtain a score value for each parameter value. For example, the lower limit value Amin of the second performance indicator A is 0, the upper limit value Amax of the second performance indicator is 100, and the parameter value of A is discretized according to the linear method. When A=2, the score of the discretized A is 2.

[0150] In the above embodiment, by discretizing the parameter value of the second performance indicator, the scoring result of each performance indicator of the battery can be more intuitively reflected, and then the battery performance parameter value of each submodule of the energy storage system obtained by weighted calculation based on the discretized parameter value of the second performance indicator can more intuitively reflect the state of the battery, and the submodule suitable for use at the current moment can be quickly determined for different working conditions.

[0151] In some optional embodiments, determining the discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator includes:

[0152] Determining an intermediate parameter value of the second performance indicator according to a relationship between the parameter value of the second performance indicator and the safe operating range of the second performance indicator;

[0153] The discretized parameter value of the second performance indicator is determined according to the optimal operating range of the second performance indicator and the intermediate parameter value of the second performance indicator.

[0154] The parameter range of the second performance indicator includes the safe operating range of the second performance indicator and the optimal operating range of the second performance indicator. The optimal operating range of the second performance indicator is a subset of the safe operating range. The safe operating range is the upper and lower limits of the second performance indicator parameter. If it exceeds the safe operating range, there will be safety hazards. For safety reasons, a certain margin is reserved, and a part of the continuous range is selected from the safe operating range as the optimal operating range.

[0155] In some embodiments, if the parameter value of the second performance indicator exceeds the safe operating range of the second performance indicator, the intermediate value of the second performance indicator is zero, and the battery performance parameter value of the submodule in the energy storage system is directly set to zero. If the parameter value of the second performance indicator is within the safe operating range of the second performance indicator, the parameter value of the second performance indicator obtained by the fitting process is determined as the intermediate parameter value of the second performance indicator. In other embodiments, the intermediate value of the second performance indicator can also be determined based on the safe operating range of the first performance indicator and the safe operating range of the second performance indicator. If the parameter value of any of the first performance indicator or the second performance indicator exceeds its corresponding safe operating range, the intermediate values ​​of all second performance indicators are zero, and then the battery performance parameter value of the submodule in the energy storage system is zero. If the parameter value of the first performance indicator and the parameter value of the second performance indicator are both within their corresponding safe operating ranges, the parameter value of the second performance indicator obtained by the fitting process is determined as the intermediate parameter value of the second performance indicator.

[0156] Then, based on the optimal operating range of the second performance indicator, the parameter values ​​within the optimal operating range are discretized to obtain a score value for each parameter value, and then the discretized score value corresponding to the parameter value is determined based on the parameter value of the second performance indicator obtained by the fitting process. Finally, a weighted calculation is performed based on the discretized parameter value of the second performance indicator to obtain the battery performance parameter value of the energy storage system.

[0157] In the above embodiment, the parameter value of the second performance indicator of the submodule within the safe operating range is screened by considering the safe operating range of the second performance indicator, and then the discretized parameter value of the second performance indicator is determined in combination with the optimal operating range of the second performance indicator. Then, the battery performance parameter value of each submodule of the energy storage system obtained by weighted calculation based on the parameter value of the discretized second performance indicator can more intuitively reflect the state of the battery, and thus the submodule suitable for use at the current moment can be quickly and safely determined.

[0158] In some optional embodiments, weighted calculation is performed based on the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of the energy storage system, including:

[0159] A weighted calculation is performed based on a preset weight coefficient of the second performance indicator and a parameter value of the discretized second performance indicator to obtain a battery performance parameter value of the energy storage system.

[0160] The weight coefficient of the preset second performance indicator represents the importance of each second performance indicator, and the weight coefficient of the preset second performance indicator is determined based on the Delphi method.

[0161] In some embodiments, the terminal calculates the product of the weight coefficient of each second performance indicator and the parameter value of the discretized second performance indicator, and accumulates the product of the weight coefficient of each second performance indicator and the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of each submodule of the energy storage system.

[0162] In the above embodiment, the battery performance parameter value of each submodule of the energy storage system is calculated based on the weight coefficient of the preset second performance indicator, so that a more accurate battery performance parameter value of the energy storage system can be obtained.

[0163] In some optional embodiments, the method for determining the weight coefficient of the preset second performance indicator includes:

[0164] Obtaining initial weight coefficients of multiple second performance indicators;

[0165] A discreteness check is performed on the plurality of initial weight coefficients, and when the initial weight coefficients pass the discreteness check, weight coefficients of the plurality of second performance indicators are obtained.

[0166] Among them, the initial weight coefficient is obtained by scoring multiple second performance indicators based on experience by multiple professionals, and the initial weight coefficient is obtained based on the weight allocation rule. For the application scenario of high-voltage and large-capacity energy storage system, the SOC difference between energy storage submodules is required to be less than 5%. The weight allocation rule includes that the sum of the initial weight coefficients of multiple second performance indicators is 1, and when the SOC difference is greater than 5%, the SOX (State OfX, SOX, battery performance parameter value) scoring order is consistent with the SOC high and low order. Professionals allocate weights to each second performance indicator based on the weight allocation rule. Since each second performance indicator is set from different angles, it can complement and verify each other. Multiple second performance indicators are not completely independent, and there are certain couplings and overlaps. Professionals will fully consider this when scoring, and take measures including but not limited to appropriately reducing the weight values ​​of certain indicators according to the correlation between the indicators to set the initial weight coefficient. After a preset number of scoring, the professional determines the initial weight coefficient, and the preset number includes but is not limited to three times.

[0167] In some embodiments, multiple professionals are obtained by scoring multiple second performance indicators based on the Delphi method and weight allocation rules to obtain initial weight coefficients, and multiple groups of initial weight coefficients are obtained, each group of initial weight coefficients includes the initial weight coefficient of each second performance indicator. In order to avoid excessive deviations in the scoring of a certain weight between experts, resulting in the evaluation being too subjective, after the professional scores, it is necessary to perform a discreteness check on the initial weight coefficients. The discreteness check method that can be used in this embodiment includes but is not limited to calculating the standard deviation of each initial weight coefficient. If the standard deviation of each initial weight coefficient is less than the preset standard deviation, the preset standard deviation includes but is not limited to 0.5, then the mean of the initial weight coefficient is used as the weight coefficient of the final second performance indicator; if the standard deviation of the initial weight coefficient is greater than 0.5, then the questionnaire is redesigned for the weight of the second performance indicator, and the expert group is scored again. After passing the discreteness check, the weight coefficient of the second performance indicator is obtained, and the weight coefficient of each second performance indicator is Ki, i = 1, 2 ... n, n is the number of second performance indicators, and this embodiment is described by taking 4 as an example.

[0168] In the above embodiment, by performing a discreteness check on the initial weight coefficient, a more accurate and reasonable weight coefficient of the second performance indicator can be obtained, and then the battery performance parameter value calculated based on the accurate weight coefficient can more accurately reflect the battery status, and thus the sub-module suitable for use at the current moment can be accurately determined.

[0169] In some optional embodiments, determining a battery performance parameter value of the energy storage system based on a parameter range of a preset performance indicator and a parameter value of a second performance indicator includes:

[0170] Determining an intermediate parameter value of the second performance indicator according to a relationship between the first performance indicator and the parameter range of the first performance indicator, and a relationship between the second performance indicator and the parameter range of the second performance indicator;

[0171] A parameter value of the battery state of charge is extracted from the intermediate parameter value for determining the second performance indicator, and a battery performance parameter value of the energy storage system is determined according to the parameter value of the battery state of charge.

[0172] The parameter range of the preset performance indicator includes the parameter range of the first performance indicator and the parameter range of the second performance indicator.

[0173] In some embodiments, in the scenario of rapid calculation of battery performance, the parameter range of the first performance indicator and the parameter range of the second performance indicator are combined to determine the battery performance parameters of each submodule of the energy storage system. In this embodiment, the parameter ranges of the first performance indicator and the second performance indicator are both safe operating ranges.

[0174] After the terminal obtains the parameter value of the first performance indicator and calculates the parameter value of the second performance indicator based on the preset performance indicator fitting processing relationship, it determines whether the parameter value of the first performance indicator is within the safe range based on the safe operating range of the first performance indicator, and determines whether the parameter value of the second performance indicator is within the safe range based on the safe operating range of the second performance indicator. If any parameter value of the first performance indicator or the parameter value of the second performance indicator exceeds the safe operating range, the battery performance parameter value of the energy storage system submodule corresponding to the parameter value is set to zero. Then, when neither the parameter value of the first performance indicator nor the parameter value of the second performance indicator exceeds the safe operating range, the parameter value of the battery state of charge is extracted from the parameter value of the second performance indicator, and the battery performance parameter value of the energy storage system is determined according to the parameter value of the battery state of charge.

[0175] In the above embodiment, since the battery state of charge has a great influence on the battery performance, in the scenario where the battery performance calculation accuracy is not high but the efficiency is high, the performance indicator parameter values ​​within the safe range are first screened according to the safe operating range of the first performance indicator and the second performance indicator. Then, when the parameter values ​​of all performance indicators of each submodule are within the safe operating range, the parameter value of the battery state of charge is directly used as the battery performance parameter value of the submodule. The battery performance of each submodule of the energy storage system can be quickly and safely determined, and the submodule that is suitable for use at the current moment can be quickly determined.

[0176] In some optional embodiments, determining a battery performance parameter value of an energy storage system according to a parameter value of a battery state of charge includes:

[0177] Determine the operating condition type of the energy storage system;

[0178] When the operating condition type is a charging operating condition, the parameter value of the battery state of charge is determined as the battery performance parameter value of the energy storage system;

[0179] When the operating condition type is a discharge operating condition, the difference between the preset battery state of charge maximum value and the battery state of charge parameter value is determined as the battery performance parameter value of the energy storage system.

[0180] Among them, the operating conditions of the energy storage system include charging conditions and discharging conditions.

[0181] In some embodiments, the terminal determines the operating condition type of the energy storage system. When the operating condition type is a charging condition, the parameter value of the battery state of charge is determined as the battery performance parameter value of the energy storage system; when the operating condition type is a discharging condition, the difference between a preset maximum value of the battery state of charge and the parameter value of the battery state of charge is determined as the battery performance parameter value of the energy storage system.

[0182] In the above embodiment, the parameter value of the battery state of charge under the current working condition is determined based on the charging and discharging working condition of the energy storage system, and then the battery performance parameter value corresponding to the sub-module of the energy storage system is determined according to the parameter value of the battery state of charge under the current working condition. For different working conditions, the sub-module suitable for use at the current moment can be quickly determined.

[0183] In some optional embodiments, before determining the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the method further includes:

[0184] Obtaining a parameter value of the battery health state of each battery in the submodule of the energy storage system, and determining a parameter value of the minimum battery health state in the submodule of the energy storage system;

[0185] The parameter value of the minimum battery health state is determined as the parameter value of the battery health state of the submodule in the energy storage system.

[0186] In some embodiments, in the process of determining the parameter value of the battery health state, since each submodule of the energy storage system contains multiple batteries connected in series or in parallel, the parameter value of the battery health state of each submodule is determined based on the barrel effect. For each submodule of the energy storage system, the parameter value of the battery health state of each battery in the submodule is obtained, the size of the parameter value of the battery health state of each battery in the submodule is compared, and the parameter value of the minimum battery health state in the submodule of the energy storage system is determined; the parameter value of the minimum battery health state is determined as the parameter value of the battery health state of the submodule in the energy storage system.

[0187] In the above embodiment, the battery health status parameter values ​​of multiple batteries in the sub-module of the comprehensive energy storage system are used to determine the battery health status of the sub-module, which can more accurately reflect the battery performance of each sub-module of the energy storage system, and further accurately determine the sub-module that is suitable for use at the current moment.

[0188] In some optional embodiments, the above method further includes:

[0189] Obtaining the parameter value of the battery state of charge of each battery in the submodule of the energy storage system;

[0190] When the operating condition type is a discharge operating condition, the parameter value of the lowest battery state of charge in the submodule in the energy storage system is determined as the calculated value of the battery state of charge of the submodule in the energy storage system;

[0191] When the operating condition type is a charging operating condition, the parameter value of the highest battery state of charge in the submodule in the energy storage system is determined as the calculated value of the battery state of charge of the submodule in the energy storage system.

[0192] In some embodiments, in the process of determining the parameter value of the battery state of charge, since each submodule of the energy storage system contains multiple batteries connected in series or in parallel, the parameter value of the battery state of charge of each submodule is determined based on the barrel effect. First, the parameter value of the battery state of charge of each battery in the submodule of the energy storage system obtained based on the fitting process is obtained, and then the operating condition type of the energy storage system is determined. When the operating condition type is a discharge condition, the parameter value of the lowest battery state of charge in the submodule of the energy storage system is determined, and the parameter value of the lowest battery state of charge in the submodule of the energy storage system is determined as the calculated value of the battery state of charge of the submodule in the energy storage system; when the operating condition type is a charging condition, the parameter value of the highest battery state of charge in the submodule of the energy storage system is determined, and the parameter value of the highest battery state of charge in the submodule of the energy storage system is determined as the calculated value of the battery state of charge of the submodule in the energy storage system. In the subsequent calculation process of the submodule battery performance parameter value, for the battery state of charge parameter value, the calculated value of the battery state of charge is selected for weighted calculation. Since the battery performance calculation is processed differently under charging and discharging conditions, the higher the weighted score of the sub-module battery performance parameter value, the more suitable it is for use, and it is uniformly applicable under charging and discharging conditions.

[0193] In the above embodiment, the battery state of charge of the submodule is determined by integrating the battery state of charge parameter values ​​of multiple batteries in the submodule of the comprehensive energy storage system and the charging and discharging conditions, which can more accurately reflect the battery performance of each submodule of the energy storage system. The submodule that is suitable for use at the current moment can be accurately determined for different working conditions.

[0194] In some optional embodiments, the above method further includes:

[0195] Determine the battery performance parameter value of each submodule of the energy storage system;

[0196] Based on the battery performance parameter value of each submodule, the submodule with the highest battery performance parameter value is determined, and the submodule with the highest battery performance parameter value is determined as the target submodule.

[0197] In some embodiments, after obtaining the battery performance parameter value of each submodule of the energy storage system, the submodule with the highest battery performance parameter value among multiple submodules of the energy storage system can be determined, and the submodule with the highest battery performance parameter value can be determined as the target submodule, which is the submodule that is most suitable for use at the current moment.

[0198] In the above embodiment, the battery performance parameter value of each submodule of the energy storage system is integrated to determine the submodule that is most suitable for use at the current moment, so that an accurate target submodule can be obtained.

[0199] In an application embodiment, if Figure 5As shown, according to the real-time control requirements of the high-voltage and large-capacity energy storage system (taking the battery performance determination every 50us as an example), the method for determining the battery performance of the energy storage system provided in the embodiment of the present application is described:

[0200] The battery voltage U, battery current I and battery temperature T are obtained by real-time sampling of each submodule of the energy storage system.

[0201] According to the predetermined preset performance index fitting processing relationship, the real-time sampling battery voltage U, battery current I, and battery temperature T are fitted to obtain the battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH. Considering the barrel effect, when discharging, the lowest SOC among the series-parallel batteries in the submodule is selected as the submodule SOC, and when charging, the highest SOC among the series-parallel batteries in the submodule is selected as the submodule SOC; the lowest SOH among the series-parallel batteries in the submodule is selected as the submodule SOH.

[0202] It is determined whether the index parameter values ​​of the battery voltage U, battery current I, battery temperature T, battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH exceed the corresponding safe operating range. If there is an index exceeding the safe operating range in a certain submodule, the battery performance parameter value SOX of the submodule is zero. If each index (the first performance index and the second performance index) in the submodule is within the safe operating range, the battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH parameter values ​​of each submodule are converted into percentages based on the optimal operating range of the index.

[0203] Then, for each submodule, the battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH parameter value converted from the percentage system are weighted and calculated based on the preset weight coefficient of the second performance indicator to obtain the SOX of the submodule. In particular, when charging, 100-SOC is multiplied by the weight coefficient of the corresponding SOC.

[0204] After the above calculations, the final SOX score of each submodule is obtained. The higher the SOX score, the more suitable the submodule is for use in this control cycle. This embodiment realizes a real-time comprehensive evaluation of the battery performance of the energy storage system, and further provides a selection basis for the priority of the energy storage submodule investment, thereby improving energy utilization and reliability and extending the service life of the system. In addition, since the SOX calculation is treated differently under charging and discharging conditions, the characteristic that the higher the SOX score, the more suitable it is for investment is uniformly applicable under charging and discharging conditions.

[0205] In an application embodiment, if Figure 6As shown, in the scenario where the real-time control demand of the high-voltage and large-capacity energy storage system (taking battery performance determination once every 50us as an example) has low requirements on calculation accuracy and high requirements on efficiency, the method for determining battery performance of the energy storage system provided in the embodiment of the present application is described:

[0206] The battery voltage U, battery current I and battery temperature T are obtained by real-time sampling of each submodule of the energy storage system.

[0207] According to the predetermined preset performance index fitting processing relationship, the real-time sampling battery voltage U, battery current I, and battery temperature T are fitted to obtain the battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH. Considering the barrel effect, when discharging, the lowest SOC among the series-parallel batteries in the submodule is selected as the submodule SOC, and when charging, the highest SOC among the series-parallel batteries in the submodule is selected as the submodule SOC; the lowest SOH among the series-parallel batteries in the submodule is selected as the submodule SOH.

[0208] Determine whether the index parameter values ​​of battery voltage U, battery current I, battery temperature T, battery SOC, battery power capability P, battery current inconsistency ξ, and battery SOH exceed the corresponding safe operating range. If there is an index exceeding the safe operating range in a submodule, the battery performance parameter value (State OfX, SOX) of the submodule is zero. If each index (the first performance index and the second performance index) in the submodule is within the safe operating range, the operating condition type of the energy storage system is considered. Under the discharge condition, the battery SOC is directly used as the SOX of the submodule, and under the charging condition, 100-SOC is used as the SOX of the submodule.

[0209] In a specific application example, taking a lithium iron phosphate battery with a rated capacity of 280Ah as an example, 10 cells are randomly selected for electrical testing to obtain test data. A fitting model is established based on the test data, and the upper and lower limits of each indicator are established. The scoring range of each performance indicator of a 280Ah battery is as follows:

[0210] Table 2 Upper and lower limits of battery performance indicators

[0211] Indicator name Upper limit Lower limit Battery SOC 100％ 0％ Battery voltage U 3.5V 2.5V Battery current I 250A 33.6A Battery temperature T 50℃ -20℃ Battery current inconsistency 5％ 0％ Battery SOH 100％ 60％ Battery power capability P 1p.u. 0.12pu

[0212] The second performance indicator is assigned a weight based on the Delphi method. For the application scenario of high-voltage and large-capacity energy storage system, the SOC difference between energy storage submodules is required to be less than 5%, so the considerations for weight allocation are as follows:

[0213] (a) The sum of the weights of each indicator is 1;

[0214] (b) When the SOC difference is greater than 5%, the order of SOX scores is consistent with the order of SOC.

[0215] Seven experts in the battery field were selected, numbered ABCDEFG. After fully understanding the requirements of high-voltage and large-capacity energy storage systems ((a) and (b)), the experts conducted three rounds of weighted scoring until the experts stopped modifying their opinions. The resulting weighted scoring table is as follows:

[0216] Table 3 Weight score table

[0217]

[0218] Calculate the standard deviation of the weighted scores of each second performance indicator, and the results are as follows:

[0219] Table 4 Standard deviation of weighted scores of each second performance indicator

[0220]

[0221]

[0222] The standard deviation of the weight scores of each indicator is less than 0.5, so the mean of each weight is taken as the final weight.

[0223] Select 4 energy storage submodules, and according to the real-time control requirements of the high-voltage and large-capacity energy storage system (taking 50us commonly used in engineering as an example), sample the energy storage submodules in real time to obtain the first performance indicators of battery voltage U, battery current I, and battery temperature T. The indicators after collection or calculation are shown in the following table:

[0224] Table 5 Index parameter table

[0225] Indicator name Submodule 1 Submodule 2 Submodule 3 Submodule 4 Battery SOC 50.02％ 48.98％ 51.32％ 53.26％ Battery voltage U 3.35V 3.33V 3.33V 3.36V Battery current I 200.4A 198.9A 201.16A 200.7A Battery temperature T 20.61℃ 19.71℃ 21.03℃ 20.76℃ Battery current inconsistency 1.4％ 0.8％ 0.9％ 1.2％ Battery SOH 98％ 88％ 95％ 92％ Battery power capability P 0.95pu 1p.u. 0.9pu 0.85pu

[0226] Each second performance index parameter value is converted into a percentage system, for example, Amin=0, Amax=100, A is any secondary index. The basis for the percentage conversion is shown in the following table:

[0227] Table 6 Reference table for conversion of each indicator into percentage system

[0228]

[0229] Here, a linear method is used for percentage conversion, and then a weighted calculation is performed with the corresponding weights, namely: SOX = SOC*K1+P*K2+SOH*K3+ξ*K4.

[0230] After calculation, the SOX scores of the four sub-modules are as follows (taking discharge as an example):

[0231] Table 7 Sub-module SOX score table

[0232] Submodule name Submodule 1 Submodule 2 Submodule 3 Submodule 4 SOX 51.67 50.28 52.84 54.48

[0233] From the above data, we can see that SOX4>SOX3>SOX1>SOX2. Therefore, at this moment of the discharge condition (based on the sampling moment), submodule 4 is most suitable for input, followed by submodule 3 and submodule 1. Submodule 2 has the lowest priority among the four submodules.

[0234] It can be seen from the above examples that the technical solution provided by the present application provides a comprehensive evaluation scheme for the evaluation of battery performance in the use scenario of high-voltage and large-capacity energy storage system. It not only overcomes the one-sidedness brought about by using a single indicator as the basis for evaluation, but also achieves real-time calculation and update, which provides a reliable theoretical basis for the evaluation of comprehensive battery performance and the further investment selection of energy storage sub-modules.

[0235] It should be understood that, although the steps in the flowcharts involved in the above embodiments are displayed in sequence according to the indication of the arrows, these steps are not necessarily executed in sequence according to the order indicated by the arrows. Unless there is a clear explanation in this article, the execution of these steps is not strictly limited in order, and these steps can be executed in other orders. Moreover, at least a part of the steps in the flowcharts involved in the above embodiments may include multiple steps or multiple stages, and these steps or stages are not necessarily executed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily carried out in sequence, but can be executed in turn or alternately with other steps or at least a part of the steps or stages in other steps.

[0236] Based on the same inventive concept, the embodiment of the present application also provides an energy storage system battery performance determination device for implementing the energy storage system battery performance determination method involved above. The implementation scheme for solving the problem provided by the device is similar to the implementation scheme recorded in the above method, so the specific limitations in one or more energy storage system battery performance determination device embodiments provided below can refer to the limitations of the energy storage system battery performance determination method above, and will not be repeated here.

[0237] In one embodiment, Figure 7 As shown, a device for determining battery performance of an energy storage system is provided, comprising: an acquisition module 702, a processing module 704 and a determination module 706, wherein:

[0238] An acquisition module 702 is used to acquire a parameter value of a first performance indicator collected by the energy storage system at a current moment;

[0239] A processing module 704 is used to process the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of the second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one first performance indicator;

[0240] The determination module 706 is used to determine the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator.

[0241] In one embodiment, the first performance indicator includes current, voltage, and temperature; the second performance indicator includes battery state of charge, battery state of health, battery power capability, and current inconsistency; the processing module 704 is also used to process the voltage in the parameter value of the first performance indicator based on the fitting processing relationship between the voltage and the battery state of charge to obtain the parameter value of the battery state of charge; based on the fitting processing relationship between the current, temperature and the battery power capability, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery power capability; based on the fitting processing relationship between the voltage, temperature and the battery state of health, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery state of health; based on the fitting processing relationship between the current and the current inconsistency, the current in the parameter value of the first performance indicator is processed to obtain the parameter value of the current inconsistency.

[0242] In one embodiment, the determination module 706 is also used to determine the operating condition type of the energy storage system; determine the calculated value of the second performance indicator under the current operating condition according to the operating condition type; and determine the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the calculated value of the second performance indicator under the current operating condition.

[0243] In one of the embodiments, the determination module 706 is also used to determine the parameter value of the battery state of charge as the calculated value of the battery state of charge under the current operating condition when the operating condition type is a discharging condition; and to determine the difference between a preset maximum value of the battery state of charge and the parameter value of the battery state of charge as the calculated value of the battery state of charge under the current operating condition when the operating condition type is a charging condition.

[0244] In one embodiment, the parameter range of the preset performance indicator includes the parameter range of the second performance indicator; the determination module 706 is also used to determine the parameter value of the discretized second performance indicator based on the parameter range of the second performance indicator; and a weighted calculation is performed based on the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of the energy storage system.

[0245] In one embodiment, the parameter range of the second performance indicator includes a safe operating range of the second performance indicator and an optimal operating range of the second performance indicator; the determination module 706 is further used to determine an intermediate parameter value of the second performance indicator based on a relationship between the parameter value of the second performance indicator and the safe operating range of the second performance indicator; and to determine a discretized parameter value of the second performance indicator based on the optimal operating range of the second performance indicator and the intermediate parameter value of the second performance indicator.

[0246] In one embodiment, the determination module 706 is further configured to perform weighted calculation based on a preset weight coefficient of the second performance indicator and a discretized parameter value of the second performance indicator to obtain a battery performance parameter value of the energy storage system.

[0247] In one embodiment, the determination module 706 is also used to obtain initial weight coefficients of multiple second performance indicators, and the initial weight coefficients are obtained based on a weight allocation rule; a discreteness check is performed on the multiple initial weight coefficients, and when the initial weight coefficients pass the discreteness check, the weight coefficients of the multiple second performance indicators are obtained.

[0248] In one embodiment, the parameter range of the preset performance indicator includes the parameter range of the first performance indicator and the parameter range of the second performance indicator; the determination module 706 is also used to determine the intermediate parameter value of the second performance indicator based on the relationship between the first performance indicator and the parameter range of the first performance indicator, and the relationship between the second performance indicator and the parameter range of the second performance indicator; extract the parameter value of the battery state of charge from the intermediate parameter value of the second performance indicator, and determine the battery performance parameter value of the energy storage system based on the parameter value of the battery state of charge.

[0249] In one embodiment, the processing module 704 is also used to obtain the parameter value of the battery health status of each battery in the submodule of the energy storage system, determine the parameter value of the minimum battery health status in the submodule of the energy storage system; and determine the parameter value of the minimum battery health status as the parameter value of the battery health status of the submodule in the energy storage system.

[0250] In one of the embodiments, the processing module 704 is also used to obtain the parameter value of the battery state of charge of each battery in the submodule of the energy storage system; when the operating condition type is a discharge condition, the parameter value of the lowest battery state of charge in the submodule of the energy storage system is determined as the parameter value of the battery state of charge of the submodule in the energy storage system; when the operating condition type is a charging condition, the parameter value of the highest battery state of charge in the submodule of the energy storage system is determined as the parameter value of the battery state of charge of the submodule in the energy storage system.

[0251] In one embodiment, the determination module 706 is also used to determine the battery performance parameter value of each submodule of the energy storage system; based on the battery performance parameter value of each submodule, determine the submodule with the highest battery performance parameter value, and determine the submodule with the highest battery performance parameter value as the target submodule.

[0252] Each module in the above-mentioned energy storage system battery performance determination device can be implemented in whole or in part by software, hardware and a combination thereof. Each of the above-mentioned modules can be embedded in or independent of the processor in the computer device in the form of hardware, or can be stored in the memory of the computer device in the form of software, so that the processor can call and execute the operations corresponding to each of the above modules.

[0253] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 8 As shown. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected through a system bus. Among them, the processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for determining the battery performance of an energy storage system is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covered on the display screen, or a button, trackball or touchpad set on the computer device housing, or an external keyboard, touchpad or mouse, etc.

[0254] Those skilled in the art will understand that Figure 8 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than those shown in the figure, or combine certain components, or have a different arrangement of components.

[0255] In one embodiment, a computer device is further provided, including a memory and a processor, wherein a computer program is stored in the memory, and the processor implements the steps in the above method embodiments when executing the computer program.

[0256] In one embodiment, a computer-readable storage medium is provided, on which a computer program is stored. When the computer program is executed by a processor, the steps in the above-mentioned method embodiments are implemented.

[0257] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0258] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiment methods can be completed by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to the memory, database or other medium used in the embodiments provided in the present application can include at least one of non-volatile and volatile memory. Non-volatile memory can include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetoresistive random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory can include random access memory (RAM) or external cache memory, etc. As an illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in each embodiment provided in this application may include at least one of a relational database and a non-relational database. Non-relational databases may include distributed databases based on blockchains, etc., but are not limited to this. The processor involved in each embodiment provided in this application may be a general-purpose processor, a central processing unit, a graphics processor, a digital signal processor, a programmable logic device, a data processing logic device based on quantum computing, etc., but are not limited to this.

[0259] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0260] The above-described embodiments only express several implementation methods of the present application, and the descriptions thereof are relatively specific and detailed, but they cannot be understood as limiting the scope of the present application. It should be pointed out that, for a person of ordinary skill in the art, several variations and improvements can be made without departing from the concept of the present application, and these all belong to the protection scope of the present application. Therefore, the protection scope of the present application shall be subject to the attached claims.

Claims

1. A method for determining battery performance of an energy storage system, characterized in that: The method comprises: Obtaining a parameter value of a first performance indicator collected by the energy storage system at the current moment; Processing the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators; Based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, a battery performance parameter value of the energy storage system is determined.

2. The method according to claim 1, characterized in that The first performance indicator includes current, voltage, and temperature; the second performance indicator includes battery state of charge, battery health status, battery power capability, and current inconsistency; The step of processing the parameter value of the first performance indicator according to the preset performance indicator fitting processing relationship to obtain the parameter value of the second performance indicator includes at least one of the following: Based on the fitting processing relationship between the voltage and the battery state of charge, the voltage in the parameter value of the first performance indicator is processed to obtain the parameter value of the battery state of charge; Based on the fitting processing relationship between the current, the temperature and the battery power capability, the current and the temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery power capability; Based on the fitting processing relationship between voltage, temperature and battery health state, the current and temperature in the parameter value of the first performance indicator are processed to obtain the parameter value of the battery health state; Based on the fitting processing relationship between the current and the current inconsistency, the current in the parameter value of the first performance indicator is processed to obtain the parameter value of the current inconsistency.

3. The method according to claim 1 or 2, characterized in that: The determining of the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes: Determining the operating condition type of the energy storage system; Determining a calculated value of a second performance indicator under the current operating condition according to the operating condition type; Based on the parameter range of the preset performance indicator and the calculated value of the second performance indicator under the current working condition, the battery performance parameter value of the energy storage system is determined.

4. The method according to claim 3, characterized in that Determining the calculated value of the second performance indicator under the current operating condition according to the operating condition type includes: When the operating condition type is a discharging operating condition, determining the parameter value of the battery state of charge as a calculated value of the battery state of charge under the current operating condition; When the operating condition type is a charging operating condition, the difference between a preset maximum value of the battery state of charge and a parameter value of the battery state of charge is determined as a calculated value of the battery state of charge under the current operating condition.

5. The method according to any one of claims 1 to 4, characterized in that: The parameter range of the preset performance indicator includes the parameter range of the second performance indicator; The determining of the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes: Determining a discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator; A weighted calculation is performed based on the parameter value of the discretized second performance indicator to obtain a battery performance parameter value of the energy storage system.

6. The method according to claim 5, characterized in that The parameter range of the second performance indicator includes a safe operating range of the second performance indicator and an optimal operating range of the second performance indicator; Determining the discretized parameter value of the second performance indicator according to the parameter range of the second performance indicator includes: Determining an intermediate parameter value of the second performance indicator according to a relationship between the parameter value of the second performance indicator and the safe operating range of the second performance indicator; A discretized parameter value of the second performance indicator is determined according to the optimal operating range of the second performance indicator and an intermediate parameter value of the second performance indicator.

7. The method according to claim 5 or 6, characterized in that: The weighted calculation based on the parameter value of the discretized second performance indicator to obtain the battery performance parameter value of the energy storage system includes: A weighted calculation is performed based on a preset weight coefficient of the second performance indicator and the parameter value of the discretized second performance indicator to obtain a battery performance parameter value of the energy storage system.

8. The method according to claim 7, characterized in that The method for determining the weight coefficient of the preset second performance indicator includes: Acquire initial weight coefficients of a plurality of second performance indicators, wherein the initial weight coefficients are obtained based on a weight allocation rule; A discreteness check is performed on the plurality of the initial weight coefficients, and when the initial weight coefficients pass the discreteness check, a plurality of weight coefficients of the second performance indicators are obtained.

9. The method according to any one of claims 1 to 4, characterized in that: The parameter range of the preset performance indicator includes the parameter range of the first performance indicator and the parameter range of the second performance indicator; The determining of the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator includes: Determining an intermediate parameter value of the second performance indicator according to a relationship between the first performance indicator and the parameter range of the first performance indicator, and a relationship between the second performance indicator and the parameter range of the second performance indicator; A parameter value of the battery state of charge is extracted from the intermediate parameter value for determining the second performance indicator, and a battery performance parameter value of the energy storage system is determined according to the parameter value of the battery state of charge.

10. The method according to any one of claims 1 to 9, characterized in that: Before determining the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator, the method further includes: Obtaining a parameter value of a battery health state of each battery in a submodule of an energy storage system, and determining a parameter value of a minimum battery health state in a submodule of the energy storage system; The parameter value of the minimum battery health state is determined as the parameter value of the battery health state of the submodule in the energy storage system.

11. The method according to claim 10, characterized in that Also includes: Obtaining the parameter value of the battery state of charge of each battery in the submodule of the energy storage system; When the operating condition type is a discharge operating condition, the parameter value of the lowest battery state of charge in the submodule of the energy storage system is determined as the parameter value of the battery state of charge of the submodule of the energy storage system; When the operating condition type is a charging operating condition, the parameter value of the highest battery state of charge in the submodule in the energy storage system is determined as the parameter value of the battery state of charge of the submodule in the energy storage system.

12. The method according to any one of claims 1 to 11, characterized in that: Also includes: Determine the battery performance parameter value of each submodule of the energy storage system; Based on the battery performance parameter value of each submodule, the submodule with the highest battery performance parameter value is determined, and the submodule with the highest battery performance parameter value is determined as the target submodule.

13. A device for determining battery performance of an energy storage system, characterized in that: The device comprises: An acquisition module, used to acquire a parameter value of a first performance indicator collected by the energy storage system at a current moment; a processing module, configured to process the parameter value of the first performance indicator according to a preset performance indicator fitting processing relationship to obtain a parameter value of a second performance indicator, wherein the preset performance indicator fitting processing relationship is obtained based on fitting of at least one of the first performance indicators; A determination module is used to determine the battery performance parameter value of the energy storage system based on the parameter range of the preset performance indicator and the parameter value of the second performance indicator.

14. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 12 are implemented.

15. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

16. A computer program product comprising a computer program, characterized in that When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 12 are implemented.

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