Estimation Method, Device and Related Equipment for State of Energy (SOE) of Energy Storage System

Abstract

The present application relates to a method, device and related equipment for estimating the State of Energy (SOE) of an energy storage system. The method includes: obtaining the current capacity and rated capacity of the energy storage system; determining the state of the energy storage system and setting the full charge voltage in the state where the energy storage system is located; obtaining the current average cell voltage of the energy storage system, comparing the current average cell voltage with the voltage threshold in the state where the energy storage system is located to obtain the final average cell voltage; estimating the SOE based on the current capacity, rated capacity, full charge voltage and the final average cell voltage to obtain the SOE in the state where the energy storage system is located, solving the technical problem of calculation deviation caused by relying on big data models and complex algorithms in the prior art, achieving the technical effect of high-precision and low-computation-burden SOE estimation, and improving the reliability and energy management efficiency of the energy storage system.

Description

Technical Field

[0001] The present application relates to the technical field of energy storage, and in particular, to a method and device for estimating the state of energy (SOE) of an energy storage system, and related equipment. Background Art

[0002] With the development of the energy storage industry, energy storage systems need to operate more efficiently and stably. The concept of SOE (state of energy of energy storage batteries) has been introduced in the field of energy storage. SOE can reflect the operating state of the energy storage system from another perspective. Currently, methods for estimating SOE include neural networks, OCV open circuit voltage method, Kalman filter algorithm, etc. However, these algorithms based on big data require a large amount of data as support. When the big data model is not accurate enough, the obtained results will also deviate.

[0003] For current energy storage systems, multi-cell series or parallel connection is the basic framework of the energy storage system. Therefore, for the entire system, it is impossible to control the capacities of dozens or hundreds of cells at the same level. Most of them are balanced and grouped during factory production. Such a processing method cannot ensure that each cell maintains a high degree of consistency in voltage and capacity during operation, which brings great difficulties to the SOE calculation of the big data type. With the charge and discharge of the energy storage system, chemical crystallization will occur inside the cells, and the capacity of the cells will decay with the number of charge and discharge cycles. It takes a lot of time to control the decay degree, and it is difficult to use as the original data of the big data model when the data is inaccurate. During the charge and discharge process, the voltage and current data are both changing, and the above algorithms will cause greater calculation errors.

[0004] Therefore, when estimating the SOE of an energy storage system in the prior art, due to relying on big data models and complex algorithms, a large amount of data support is required, and it is difficult to ensure the consistency of voltage and capacity of each cell in the case of multi-cell series or parallel connection, resulting in calculation deviations. Especially when the voltage and current data change greatly during the charge and discharge process, the error further increases.

[0005] In response to the above problems, no effective solution has been proposed yet. Summary of the Invention

[0006] Embodiments of the present application provide a method and device for estimating the SOE of an energy storage system, and related equipment, so as to at least solve the technical problem of calculation deviation caused by relying on big data models and complex algorithms in the prior art.

[0007] According to one aspect of the embodiments of the present application, a method for estimating the state of charge (SOC) of an energy storage system is provided, including: obtaining the current capacity and the rated capacity of the energy storage system; determining the state in which the energy storage system is located, and setting the full charge voltage in the state in which the energy storage system is located; wherein, the state in which the energy storage system is located includes at least one of the following: charging state, discharging state, and static state; obtaining the current average cell voltage of the energy storage system, comparing the current average cell voltage with the voltage threshold in the state in which the energy storage system is located, to obtain the final average cell voltage; performing SOC estimation according to the current capacity, the rated capacity, the full charge voltage, and the final average cell voltage, to obtain the SOC in the state in which the energy storage system is located.

[0008] Optionally, setting the full charge voltage in the state in which the energy storage system is located includes: when the state in which the energy storage system is located is the charging state, setting a first preset voltage as the full charge voltage; wherein, the first preset voltage is the voltage when the cells in the energy storage system are fully charged; when the state in which the energy storage system is located is the discharging state or the static state, setting a second preset voltage as the full charge voltage; wherein, the second preset voltage is the voltage after the cells in the energy storage system are fully charged and left static for a period of time.

[0009] Optionally, when the state in which the energy storage system is located is the charging state, the voltage threshold includes the first preset voltage, the first preset voltage is the voltage when the cells in the energy storage system are fully charged, comparing the current average cell voltage with the voltage threshold in the state in which the energy storage system is located, to obtain the final average cell voltage, includes: determining whether the current average cell voltage is greater than or equal to the first preset voltage; if the current average cell voltage is greater than or equal to the first preset voltage, then setting the first preset voltage as the final average cell voltage; if the current average cell voltage is less than the first preset voltage, then setting the current average cell voltage as the final average cell voltage.

[0010] Optionally, when the state of the energy storage system is the discharging state, the voltage threshold includes a third preset voltage, which is the voltage of the battery cells in the energy storage system after being discharged and left standing for a period of time. Comparing the current average battery cell voltage with the voltage threshold in the state of the energy storage system to obtain the final average battery cell voltage includes: determining whether the current average battery cell voltage is less than or equal to the third preset voltage; if the current average battery cell voltage is less than or equal to the third preset voltage, setting the third preset voltage as the final average battery cell voltage; if the current average battery cell voltage is greater than the third preset voltage, setting the current average battery cell voltage as the final average battery cell voltage.

[0011] Optionally, when the state of the energy storage system is the standing state, the voltage threshold includes a second preset voltage and a third preset voltage. The second preset voltage is the voltage of the battery cells in the energy storage system after being fully charged and left standing for a period of time, and the third preset voltage is the voltage of the battery cells in the energy storage system after being discharged and left standing for a period of time. Comparing the current average battery cell voltage with the voltage threshold in the state of the energy storage system to obtain the final average battery cell voltage includes: determining whether the current average battery cell voltage is less than or equal to the third preset voltage; if the current average battery cell voltage is less than or equal to the third preset voltage, setting the third preset voltage as the final average battery cell voltage; if the current average battery cell voltage is greater than the third preset voltage, determining whether the current average battery cell voltage is greater than or equal to the second preset voltage; if the current average battery cell voltage is greater than or equal to the second preset voltage, setting the second preset voltage as the final average battery cell voltage; if the current average battery cell voltage is less than the second preset voltage, setting the current average battery cell voltage as the final average battery cell voltage.

[0012] Optionally, SOE estimation is performed based on the current capacity, the rated capacity, the full charge voltage, and the final average battery cell voltage to obtain the SOE in the state of the energy storage system, including: multiplying the current capacity by the final average battery cell voltage to obtain the current remaining energy of the energy storage system; multiplying the rated capacity by the full charge voltage to obtain the maximum storage energy of the energy storage system; dividing the current remaining energy of the energy storage system by the maximum storage energy of the energy storage system to obtain the SOE in the state of the energy storage system.

[0013] According to another aspect of the embodiments of the present application, there is provided an estimation device for the state of charge (SOC) of an energy storage system, including: a capacity acquisition module configured to acquire the current capacity and the rated capacity of the energy storage system; a voltage setting module configured to determine the state of the energy storage system and set the full charge voltage in the state of the energy storage system; wherein, the state of the energy storage system includes at least one of the following: a charging state, a discharging state, and a static state; a voltage comparison module configured to acquire the current average cell voltage of the energy storage system, compare the current average cell voltage with a voltage threshold in the state of the energy storage system, and obtain the final average cell voltage; an SOC estimation module configured to perform SOC estimation based on the current capacity, the rated capacity, the full charge voltage, and the final average cell voltage, and obtain the SOC in the state of the energy storage system.

[0014] According to another aspect of the embodiments of the present application, there is provided an electronic device, including: a processor, and a memory storing a program, the program including instructions that, when executed by the processor, cause the processor to execute the method for estimating the state of charge (SOC) of the energy storage system according to any one of the above.

[0015] According to another aspect of the embodiments of the present application, there is provided a non-transitory machine-readable medium storing computer instructions for causing a computer to execute the method for estimating the state of charge (SOC) of the energy storage system according to the above.

[0016] According to another aspect of the embodiments of the present application, there is provided a computer program product, including a computer program, optionally, the computer program, when executed by a processor of a computer, is configured to cause the computer to execute the method for estimating the state of charge (SOC) of the energy storage system according to the above.

[0017] In the embodiments of the present application, the method includes: acquiring the current capacity and the rated capacity of the energy storage system; determining the state of the energy storage system and setting the full charge voltage in the state of the energy storage system; wherein, the state of the energy storage system includes at least one of the following: a charging state, a discharging state, and a static state; acquiring the current average cell voltage of the energy storage system, comparing the current average cell voltage with a voltage threshold in the state of the energy storage system, and obtaining the final average cell voltage; performing SOC estimation based on the current capacity, the rated capacity, the full charge voltage, and the final average cell voltage, and obtaining the SOC in the state of the energy storage system. That is, in the embodiments of the present application, by dynamically setting the full charge voltage, introducing a voltage threshold comparison mechanism, and combining the ampere-hour accumulation method and voltage processing, the technical problem of calculation deviation caused by relying on big data models and complex algorithms in the prior art is solved, and the technical effects of achieving high-precision and low-computation-burden SOC estimation and improving the reliability and energy management efficiency of the energy storage system are achieved. Description of the Drawings

[0018] To more clearly illustrate the technical solutions in the embodiments of the present application or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present application. For those of ordinary skill in the art, without creative efforts, other embodiments can also be obtained based on these drawings.

[0019] Figure 1 It is a flowchart of the estimation method for the state of energy (SOE) of the energy storage system provided in the embodiment of the present application;

[0020] Figure 2 It is a flowchart of the estimation method for the state of energy (SOE) of the energy storage system provided in the alternative embodiment of the present application;

[0021] Figure 3 It is a schematic diagram of the estimation device for the state of energy (SOE) of the energy storage system provided in the embodiment of the present application;

[0022] Figure 4 It is a schematic diagram of the structure of the electronic device provided in the embodiment of the present application. Detailed implementation manners

[0023] The following will describe the embodiments of the present application in more detail with reference to the drawings. Although some embodiments of the present application are shown in the drawings, it should be understood that the embodiments of the present application can be implemented in various forms and should not be construed as limited to the embodiments described herein. Instead, these embodiments are provided to more thoroughly and completely understand the embodiments of the present application. It should be understood that the drawings and embodiments of the present application are only for exemplary purposes and are not used to limit the protection scope of the present application.

[0024] According to one aspect of the embodiments of the present application, a method for estimating the state of energy (SOE) of an energy storage system is provided. Figure 1 It is a flowchart of the estimation method for the state of energy (SOE) of the energy storage system provided in the embodiment of the present application. As Figure 1 shown, the method includes the following steps:

[0025] Step S102, obtaining the current capacity and the rated capacity of the energy storage system.

[0026] For example, by using the battery management system (BMS) to monitor and calculate the current capacity of the energy storage system in real time and using the calibrated rated capacity as a reference, the accuracy of capacity calculation can be improved, and the influence of capacity attenuation caused by cell aging or increased charge and discharge times on the estimation result can be avoided.

[0027] Step S104, determine the state of the energy storage system and set the full charge voltage in the state of the energy storage system; wherein, the state of the energy storage system includes at least one of the following: charging state, discharging state, and static state.

[0028] According to the state of the energy storage system (charging, discharging, or static), the corresponding full charge voltage is dynamically set. This way of dynamically setting the full charge voltage can better adapt to the voltage change characteristics of the battery cells in different states and reduce the error caused by state changes. For example, in the charging state: the full charge voltage is set to 3600 mV (the voltage when the battery cell is fully charged). In the discharging state: the full charge voltage is set to 3350 mV (the static full charge voltage after the battery cell is fully charged and left standing for a period of time). In the static state: according to the comparison between the average voltage of the battery cell and the threshold, 3350 mV (static full charge voltage) or 3000 mV (static discharge voltage) is selected as the full charge voltage.

[0029] Step S106, obtain the current average voltage of the battery cells in the energy storage system, compare the current average voltage with the voltage threshold in the state of the energy storage system, and obtain the final average voltage of the battery cells.

[0030] In each state, through the voltage threshold comparison mechanism, the final average voltage of the battery cells is determined. This voltage threshold comparison mechanism can use a fixed voltage value for SOE estimation when the battery cells are close to full charge or fully discharged, avoiding the influence of voltage fluctuations on the result. For example, in the charging state: if the current average voltage of the battery cells is greater than or equal to 3600 mV, then 3600 mV is used as the final average voltage of the battery cells; otherwise, the current average voltage is used. In the discharging state or static state: if the current average voltage of the battery cells is less than or equal to 3000 mV, then 3000 mV is used as the final average voltage of the battery cells; otherwise, continue to judge whether it is greater than or equal to 3350 mV and then decide which voltage value to use.

[0031] Step S108, perform SOE estimation based on the current capacity, rated capacity, full charge voltage, and the final average voltage of the battery cells to obtain the SOE in the state of the energy storage system.

[0032] By multiplying the current capacity by the final average voltage of the battery cells, the current remaining energy is obtained; by multiplying the rated capacity by the full charge voltage, the maximum stored energy is obtained; then, by dividing the current remaining energy by the maximum stored energy, the SOE in the state of the energy storage system is obtained. This SOE estimation method based on the ampere-hour accumulation method and voltage processing can achieve relatively accurate energy state estimation without relying on complex big data models.

[0033] In the embodiment of the present application, the current capacity and rated capacity of the energy storage system are acquired; the state of the energy storage system is determined, and the full charge voltage in the state of the energy storage system is set; wherein, the state of the energy storage system includes at least one of the following: charging state, discharging state, and static state; the current average cell voltage of the energy storage system is acquired, and the current average cell voltage is compared with the voltage threshold in the state of the energy storage system to obtain the final average cell voltage; the state of charge (SOC) of the energy storage system is estimated according to the current capacity, rated capacity, full charge voltage, and the final average cell voltage, that is, in the embodiment of the present application, by dynamically setting the full charge voltage, introducing a voltage threshold comparison mechanism, and combining the ampere-hour integration method and voltage processing, the technical problem of calculation deviation caused by relying on big data models and complex algorithms in the prior art is solved, and the technical effect of achieving high-precision and low-computation-burden SOC estimation and improving the reliability and energy management efficiency of the energy storage system is achieved.

[0034] It should be noted that the voltage threshold in the embodiment of the present application can be flexibly set according to the needs of the application scenario.

[0035] As an optional embodiment, setting the full charge voltage in the state of the energy storage system includes: when the state of the energy storage system is the charging state, setting the first preset voltage as the full charge voltage; wherein, the first preset voltage is the voltage when the cells in the energy storage system are fully charged; when the state of the energy storage system is the discharging state or the static state, setting the second preset voltage as the full charge voltage; wherein, the second preset voltage is the voltage after the cells in the energy storage system are fully charged and left standing for a period of time.

[0036] Optionally, when the energy storage system is in the charging state, the first preset voltage (3600 mV) is set as the full charge voltage. At this time, the first preset voltage represents the voltage when the cells reach the fully charged state during charging. This voltage value is determined based on the characteristics of lithium iron phosphate batteries to ensure that the actual charging state of the cells can be accurately reflected during charging.

[0037] Optionally, when the energy storage system is in the discharging state or the static state, the second preset voltage (3350 mV) is set as the full charge voltage. The second preset voltage is called the static full charge voltage, which refers to the stable voltage after the cells are fully charged and left standing for a period of time. For the discharging state, using the static full charge voltage as a reference can more accurately estimate the remaining energy state of the cells during discharging. For the static state, using the static full charge voltage can avoid voltage fluctuations caused by self-discharge or other factors, thereby providing a more stable SOC estimation.

[0038] In the embodiments of the present application, by distinguishing different system states and setting corresponding full charge voltages, the errors caused by state changes can be reduced, and the estimation accuracy of SOE can be improved. Setting different full charge voltages in different states fully considers the voltage change characteristics of the battery cells during the charge and discharge processes, making the SOE estimation more in line with the actual working conditions.

[0039] As an optional embodiment, when the state of the energy storage system is the charging state, the voltage threshold includes a first preset voltage, and the first preset voltage is the voltage when the battery cells in the energy storage system are fully charged. Comparing the current average battery cell voltage with the voltage threshold in the state of the energy storage system to obtain the final average battery cell voltage includes: determining whether the current average battery cell voltage is greater than or equal to the first preset voltage; if the current average battery cell voltage is greater than or equal to the first preset voltage, then setting the first preset voltage as the final average battery cell voltage; if the current average battery cell voltage is less than the first preset voltage, then setting the current average battery cell voltage as the final average battery cell voltage.

[0040] Optionally, when the energy storage system is in the charging state, set the first preset voltage to 3600 mV, which is the voltage when the battery cells are fully charged. Real-time collect the voltages of each battery cell in the energy storage system and calculate the average voltage of the battery cells in a single cluster of the energy storage system. Compare the current average battery cell voltage with the first preset voltage (3600 mV) to determine whether the current average battery cell voltage is greater than or equal to the first preset voltage. If the current average battery cell voltage is greater than or equal to the first preset voltage (3600 mV), then set the first preset voltage (3600 mV) as the final average battery cell voltage. This indicates that the battery cells are close to or have reached the fully charged state. If the current average battery cell voltage is less than the first preset voltage (3600 mV), then set the current average battery cell voltage as the final average battery cell voltage. This indicates that the battery cells are not fully charged and need to continue charging.

[0041] Furthermore, according to the finally determined average battery cell voltage, combined with the current capacity and the rated capacity calculated by the ampere-hour accumulation method, further calculate the SOE of the energy storage system. In the charging state, the full energy voltage of the battery cells is set to 3600 mV for SOE calculation.

[0042] In the embodiments of the present application, by introducing a voltage threshold comparison mechanism, it is ensured that the cell voltage will not exceed its full charge voltage during the charging process, avoiding overcharging. At the same time, when the cell is approaching the full charge voltage, the voltage parameter in the SOE calculation can be adjusted in a timely manner, improving the accuracy of SOE estimation. This method can use the actually measured average voltage for SOE calculation when the cell is not fully charged, and use a fixed full charge voltage for calculation when the cell is approaching full charge, thereby reducing the error caused by voltage fluctuations. This method fully considers the voltage change characteristics of lithium iron phosphate batteries during the charging process, ensuring the accuracy of SOE estimation. Especially when the cell is approaching full charge, using a fixed full charge voltage can effectively cope with the small fluctuations in the cell voltage, providing a more stable SOE estimation result.

[0043] As an alternative embodiment, when the energy storage system is in a discharging state, the voltage threshold includes a third preset voltage, and the third preset voltage is the voltage of the cell in the energy storage system after it has been discharged and left standing for a period of time. Comparing the current average cell voltage with the voltage threshold in the state of the energy storage system to obtain the final average cell voltage includes: determining whether the current average cell voltage is less than or equal to the third preset voltage; if the current average cell voltage is less than or equal to the third preset voltage, then setting the third preset voltage as the final average cell voltage; if the current average cell voltage is greater than the third preset voltage, then setting the current average cell voltage as the final average cell voltage.

[0044] Optionally, when the energy storage system is in a discharging state, the third preset voltage is set to 3000 mV, which is the static discharge voltage of the cell after it has been discharged and left standing for a period of time. This voltage value reflects the stable voltage reached by the cell after being fully discharged and left standing for a period of time. The voltage of each cell in the energy storage system is collected in real time, and the average voltage of the cells in a single cluster of the energy storage system is calculated.

[0045] Compare the current average cell voltage with the third preset voltage (3000 mV) to determine whether the current average cell voltage is less than or equal to the third preset voltage. If the current average cell voltage is less than or equal to the third preset voltage (3000 mV), then set the third preset voltage (3000 mV) as the final average cell voltage. This indicates that the cell has approached or reached the fully discharged state. If the current average cell voltage is greater than the third preset voltage (3000 mV), then set the current average cell voltage as the final average cell voltage. This indicates that the cell has not been fully discharged and still has a certain amount of remaining energy.

[0046] Further, according to the finally determined average voltage of the battery cell, combined with the current capacity and the rated capacity calculated by the ampere-hour accumulation method, the State of Energy (SOE) of the energy storage system is further calculated. In the discharge state, the full energy voltage of the battery cell is set as the static full charge voltage of 3350 mV for SOE calculation.

[0047] In the embodiment of the present application, by introducing a voltage threshold comparison mechanism, it is ensured that the battery cell voltage will not be lower than its discharge cut-off voltage during the discharge process, avoiding the occurrence of over-discharge phenomenon. At the same time, when the battery cell is close to the discharge cut-off voltage, the voltage parameters in the SOE calculation can be adjusted in a timely manner, improving the accuracy of SOE estimation. This method can use the actually measured average voltage for SOE calculation when the battery cell is not fully discharged, and use a fixed discharge cut-off voltage for calculation when the battery cell is close to full discharge, thereby reducing the error caused by voltage fluctuations. This method fully considers the voltage change characteristics of the lithium iron phosphate battery during the discharge process, ensuring the accuracy of SOE estimation. Especially when the battery cell is close to full discharge, using a fixed discharge cut-off voltage can effectively cope with the small fluctuations of the battery cell voltage, providing a more stable SOE estimation result. During the discharge process, the battery cell voltage may fluctuate due to self-discharge or other factors. By setting the third preset voltage as the static discharge cut-off voltage, the system can provide a stable reference voltage when the battery cell is close to full discharge, avoiding the influence of voltage fluctuations on SOE estimation and improving the overall stability of the system.

[0048] As an optional embodiment, when the energy storage system is in a static state, the voltage threshold includes a second preset voltage and a third preset voltage. The second preset voltage is the voltage of the battery cell in the energy storage system after being fully charged and left standing for a period of time, and the third preset voltage is the voltage of the battery cell in the energy storage system after being fully discharged and left standing for a period of time. Comparing the current average voltage of the battery cell with the voltage threshold in the state of the energy storage system to obtain the final average voltage of the battery cell includes: determining whether the current average voltage of the battery cell is less than or equal to the third preset voltage; if the current average voltage of the battery cell is less than or equal to the third preset voltage, then setting the third preset voltage as the final average voltage of the battery cell; if the current average voltage of the battery cell is greater than the third preset voltage, then determining whether the current average voltage of the battery cell is greater than or equal to the second preset voltage; if the current average voltage of the battery cell is greater than or equal to the second preset voltage, then setting the second preset voltage as the final average voltage of the battery cell; if the current average voltage of the battery cell is less than the second preset voltage, then setting the current average voltage of the battery cell as the final average voltage of the battery cell.

[0049] Optionally, the second preset voltage is set to 3350 mV, which is the static full charge voltage after the battery cell has been charged and left standing for a period of time. The third preset voltage is set to 3000 mV, which is the static discharge voltage after the battery cell has been discharged and left standing for a period of time. The voltage of each battery cell in the energy storage system is collected in real time, and the average voltage of the battery cells in a single cluster of the energy storage system is calculated. The current average battery cell voltage is compared with the third preset voltage (3000 mV) to determine whether the current average battery cell voltage is less than or equal to the third preset voltage. If the current average battery cell voltage is less than or equal to the third preset voltage (3000 mV), then the third preset voltage (3000 mV) is set as the final average battery cell voltage. This indicates that the battery cell has approached or reached a fully discharged state. If the current average battery cell voltage is greater than the third preset voltage (3000 mV), then the next comparison is continued: determining whether the current average battery cell voltage is greater than or equal to the second preset voltage (3350 mV). If the current average battery cell voltage is greater than or equal to the second preset voltage (3350 mV), then the second preset voltage (3350 mV) is set as the final average battery cell voltage. This indicates that the battery cell has approached or reached a fully charged state. If the current average battery cell voltage is less than the second preset voltage (3350 mV), then the current average battery cell voltage is set as the final average battery cell voltage. This indicates that the battery cell is neither fully discharged nor fully charged and is in an intermediate state.

[0050] Furthermore, based on the finally determined average battery cell voltage, combined with the current capacity and the rated capacity calculated by the ampere-hour accumulation method, the state of energy (SOE) of the energy storage system is further calculated. In the static state, the static full charge voltage (3350 mV) and the static discharge voltage (3000 mV) are used as references to ensure more accurate SOE estimation.

[0051] In the embodiment of the present application, by introducing two voltage thresholds (the second preset voltage and the third preset voltage), the actual state of the battery cell can be more accurately reflected in the static state. Whether it is approaching full charge or approaching full discharge, the SOE can be estimated using fixed voltage values, reducing the error caused by voltage fluctuations. This method can use the actually measured average voltage for SOE calculation when the battery cell is in an intermediate state, and use fixed voltage values for calculation when the battery cell is approaching full charge or full discharge, thereby improving the accuracy of SOE estimation. This method fully considers the voltage change characteristics of the lithium iron phosphate battery in the static state, ensuring the accuracy of SOE estimation. Especially when the battery cell is approaching full charge or full discharge, using fixed voltage values can effectively cope with the small fluctuations in the battery cell voltage and provide a more stable SOE estimation result.

[0052] As an alternative embodiment, the State of Energy (SOE) is estimated based on the current capacity, rated capacity, full charge voltage, and the final average cell voltage to obtain the SOE of the energy storage system in its current state, including: multiplying the current capacity by the final average cell voltage to obtain the current remaining energy of the energy storage system; multiplying the rated capacity by the full charge voltage to obtain the maximum storage energy of the energy storage system; and dividing the current remaining energy of the energy storage system by the maximum storage energy of the energy storage system to obtain the SOE of the energy storage system in its current state.

[0053] The above-mentioned current capacity is the energy currently stored in the energy storage system, with the unit of Ah (ampere-hour), which is monitored and calculated by the BMS in real time. The above-mentioned rated capacity is the nominal capacity of the energy storage system, i.e., the maximum energy that can be stored under ideal conditions, with the unit of Ah. The above-mentioned full charge voltage is the voltage when the cell is fully charged, and the specific value depends on the cell type. For example, the full charge voltage of a lithium iron phosphate battery is usually 3600 mV. The above-mentioned final average cell voltage is the final average cell voltage determined by comparing voltage thresholds according to the state of the energy storage system (charging, discharging, or idle).

[0054] Optionally, the calculated SOE value is output to the user or the control system for monitoring the energy state of the energy storage system, and based on this, operations such as charge and discharge management and load distribution are carried out.

[0055] In the embodiment of the present application, by introducing the final average cell voltage as a key parameter for calculating the current remaining energy, this method can more accurately reflect the actual working state of the cell. Especially when the cell is close to full charge or completely discharged, using a fixed voltage value for calculation reduces the error caused by voltage fluctuations and improves the accuracy of SOE estimation. This method combines the current integration method (ampere-hour accumulation method) and voltage processing, and can achieve relatively accurate SOE estimation without relying on complex models, and is applicable to various working conditions. Through accurate SOE estimation, users can better understand the energy state of the energy storage system, thereby optimizing the energy management strategy. For example, charging in time when the power is insufficient, or reasonably distributing the load when the power is sufficient to avoid unnecessary energy waste. This method can also be used to predict the remaining available time of the energy storage system, helping users make advance plans to ensure the stable operation of the system.

[0056] The following will elaborate on the alternative embodiment of the present application in combination with lithium iron phosphate batteries in the field of energy storage.

[0057] An alternative embodiment of the present application provides a method for estimating the state of charge (SOC) of a lithium iron phosphate battery applicable to the energy storage field. Based on the macroscopic concept of energy conservation, it bypasses relatively complex calculation methods such as big data models. At the same time, it obtains the true effective capacity of the energy storage system through capacity calibration, without calculating heat loss and power loss of other external devices, thus ensuring the accuracy of capacity calculation and SOC to the greatest extent. The specific steps are as follows:

[0058] 1. System capacity calculation:

[0059] First, the battery management system (BMS) collects the charge and discharge current (the sampling resolution is preferably ensured to be higher than one-thousandth). If the current changes during the non-constant current charging process of the energy storage system, the hysteresis of current sampling should be kept within 100 ms (i.e., update the current data within 100 ms). The accuracy deviation of current sampling and the sampling hysteresis of current will cause continuous deviation in ampere-hour accumulation, and the calculated capacity deviation will gradually increase with the change of current.

[0060] To calculate the remaining capacity by ampere-hour accumulation, if the capacity accuracy of ampere-hour accumulation is to be high, it needs to be optimized from two aspects. The first is to meet the above-mentioned current sampling accuracy and hysteresis, and the second is that the timer or operating cycle of the battery management system of the energy storage system needs to be of high precision. Currently, most of the BMSs used in energy storage systems are single-chip microcomputers or ARM processors, and the integration method also uses discrete calculation, so the requirement for the timing cycle is very high.

[0061] Introduce the capacity attenuation of the energy storage system to further improve the calculation accuracy of the system capacity (i.e., rated capacity calibration). When the energy storage system undergoes a full charge and full discharge (i.e., from full charge to full discharge), the true capacity can be calculated, and then the calculated capacity is used as the current rated capacity of the energy storage system to participate in the SOC calculation.

[0062] The above ampere-hour accumulation method can calculate the true capacity of the current system. The product of the capacity and the cell voltage is the current remaining energy of the system. When the charge and discharge state of the system changes, the full charge voltage of the system also has different performances.

[0063] 2. Voltage processing:

[0064] The cell voltage data of the energy storage system is the second parameter for calculating the SOC. For a single-cluster energy storage system, the average value of the single-cell voltage is used to calculate the SOC of the energy storage system.

[0065] Meanwhile, the full energy voltage of the battery cells in the energy storage system also varies in different charge and discharge states. Take lithium iron phosphate batteries as an example. During charging, the full charge voltage is 3600 mV, during discharging, the emptying voltage is 2800 mV, the static full charge voltage when the system is at rest is 3350 mV (static full charge voltage: the voltage that stabilizes after the battery cells are fully charged and left standing for a period of time), the static emptying voltage when the system is at rest is 3000 mV (static emptying voltage: the voltage that stabilizes after the battery cells are fully discharged and left standing for a period of time), and the rated voltage is 3200 mV.

[0066] 3. Calculate SOE according to the system state:

[0067] During system charging: During charging, the current capacity of the energy storage system is the value calculated by ampere-hour integration, the rated capacity is the capacity of the system after calibration, and the full energy voltage of the battery cells needs to be set to 3600 mV during the charging process. The SOE calculation formula during charging is as follows:

[0068]

[0069] During system discharging: During discharging, the full energy voltage of the battery cells is the static full charge voltage of 3350 mV. The calculation formula is as follows:

[0070]

[0071] When the system is at rest: When at rest, the full energy voltage of the battery cells is the static full charge voltage of 3350 mV. The calculation formula is as follows:

[0072]

[0073] 4. SOE filtering and debouncing:

[0074] When the energy storage system is not discharging, the SOE cannot decay. When the energy storage system is not charging, the SOE cannot increase. When the battery cell voltage is lower than the static emptying voltage of 3000 mV and the energy storage system is not charging or discharging, it can represent that the current system has emptied its power, and the current calculated average voltage is taken as the static emptying voltage.

[0075] When the system is at rest, if the average voltage is higher than the static full charge voltage of 3350 mV, it represents that the system is fully charged, and the current average voltage is the static full charge voltage.

[0076] Figure 2 The flowchart of the method for estimating the SOE of the energy storage system provided by the optional embodiment of the present application is as Figure 2As shown, first, obtain the current capacity of the energy storage system. Determine whether the energy storage system is in a charge / discharge state. If it is in a charge / discharge state, determine whether it is charging or discharging. If it is in a charging state: set the full charge voltage to 3600 mV; determine whether the current voltage (corresponding to the above-mentioned current average cell voltage) is less than 3600 mV; if so, maintain the current voltage at 3600 mV, if not, obtain the current voltage. If it is in a discharging state: set the full charge voltage to 3350 mV; determine whether the current voltage is less than 3000 mV; if so, maintain the current voltage at 3000 mV; if not, obtain the current voltage. If it is not in a charge / discharge state: set the full charge voltage to 3350 mV; determine whether the current voltage is less than 3000 mV; if so, maintain the current voltage at 3000 mV; if not, determine whether the current voltage is greater than 3350 mV; if so, save the current voltage at 3350 mV; if not, obtain the current voltage. Perform SOE estimation based on the current capacity, rated capacity, full charge voltage, and the final average cell voltage.

[0077] Through the above steps, it is possible to dynamically adjust the full charge voltage according to the state of the energy storage system, and determine the final average cell voltage through a voltage threshold comparison mechanism, thereby achieving high-precision SOE estimation.

[0078] Compared with the prior art, the optional embodiments of the present application have the following advantages:

[0079] (1) The optional embodiments of the present application propose a method for estimating the SOE of lithium iron phosphate in the energy storage field, which calculates the SOE with less data volume and computing power, improving the overall stability and reliability of the system.

[0080] (2) By means of ampere-hour accumulation, the upfront large data investment is reduced, saving the R & D cost and the complexity of R & D.

[0081] (3) It is more accurate with small errors. Ampere-hour accumulation and voltage acquisition can currently achieve relatively accurate values in the energy storage industry. This solution only introduces these two variables for SOE calculation, enabling more accurate SOE calculation.

[0082] According to another aspect of the embodiments of the present application, an apparatus for estimating the SOE of an energy storage system is provided. Figure 3 The schematic diagram of the apparatus for estimating the SOE of the energy storage system provided by the embodiments of the present application is as Figure 3 shown. The apparatus for estimating the SOE of the energy storage system includes: a capacity acquisition module 302, a voltage setting module 304, a voltage comparison module 306, and an SOE estimation module 308. The apparatus for estimating the SOE of the energy storage system will be described in detail below.

[0083] The capacity acquisition module 302 is configured to obtain the current capacity and the rated capacity of the energy storage system;

[0084] A voltage setting module 304, connected to the above-mentioned capacity acquisition module 302, is configured to determine the state of the energy storage system and set the full charge voltage in the state of the energy storage system; wherein, the state of the energy storage system includes at least one of the following: charging state, discharging state, and static state;

[0085] A voltage comparison module 306, connected to the above-mentioned voltage setting module 304, is configured to obtain the current average cell voltage of the energy storage system, compare the current average cell voltage with the voltage threshold in the state of the energy storage system, and obtain the final average cell voltage;

[0086] An SOE estimation module 308, connected to the above-mentioned voltage comparison module 306, is configured to perform SOE estimation based on the current capacity, rated capacity, full charge voltage, and the final average cell voltage to obtain the SOE in the state of the energy storage system.

[0087] In the embodiment of the present application, the device adopts obtaining the current capacity and rated capacity of the energy storage system; determining the state of the energy storage system and setting the full charge voltage in the state of the energy storage system; wherein, the state of the energy storage system includes at least one of the following: charging state, discharging state, and static state; obtaining the current average cell voltage of the energy storage system, comparing the current average cell voltage with the voltage threshold in the state of the energy storage system, and obtaining the final average cell voltage; performing SOE estimation based on the current capacity, rated capacity, full charge voltage, and the final average cell voltage to obtain the SOE in the state of the energy storage system. That is, in the embodiment of the present application, by dynamically setting the full charge voltage, introducing a voltage threshold comparison mechanism, and combining the ampere-hour accumulation method and voltage processing, the technical problem of calculation deviation caused by relying on big data models and complex algorithms in the prior art is solved, and the technical effect of achieving high-precision and low-computation-burden SOE estimation and improving the reliability and energy management efficiency of the energy storage system is achieved.

[0088] It should be noted here that the above-mentioned capacity acquisition module 302, voltage setting module 304, voltage comparison module 306, and SOE estimation module 308 correspond to steps S102 to S108 in the method embodiment. The examples and application scenarios implemented by the above modules and the corresponding steps are the same, but are not limited to the content disclosed in the above method embodiment.

[0089] Optionally, the above voltage setting module 304 includes: a first voltage setting unit configured to set a first preset voltage as the full charge voltage when the energy storage system is in a charging state; wherein the first preset voltage is the voltage when the battery cells in the energy storage system are fully charged; a second voltage setting unit configured to set a second preset voltage as the full charge voltage when the energy storage system is in a discharging state or a static state; wherein the second preset voltage is the voltage after the battery cells in the energy storage system are fully charged and left static for a period of time.

[0090] Optionally, when the energy storage system is in a charging state, the voltage threshold includes a first preset voltage, which is the voltage when the battery cells in the energy storage system are fully charged. The above voltage comparison module 306 includes: a first determination unit configured to determine whether the current average battery cell voltage is greater than or equal to the first preset voltage; a third voltage setting unit configured to, if the current average battery cell voltage is greater than or equal to the first preset voltage, set the first preset voltage as the final average battery cell voltage; a fourth voltage setting unit configured to, if the current average battery cell voltage is less than the first preset voltage, set the current average battery cell voltage as the final average battery cell voltage.

[0091] Optionally, when the energy storage system is in a discharging state, the voltage threshold includes a third preset voltage, which is the voltage after the battery cells in the energy storage system are discharged and left static for a period of time. The above voltage comparison module 306 includes: a second determination unit configured to determine whether the current average battery cell voltage is less than or equal to the third preset voltage; a fifth voltage setting unit configured to, if the current average battery cell voltage is less than or equal to the third preset voltage, set the third preset voltage as the final average battery cell voltage; a sixth voltage setting unit configured to, if the current average battery cell voltage is greater than the third preset voltage, set the current average battery cell voltage as the final average battery cell voltage.

[0092] Optionally, when the energy storage system is in a stationary state, the voltage threshold includes a second preset voltage and a third preset voltage. The second preset voltage is the voltage after the battery cells in the energy storage system are fully charged and left stationary for a period of time, and the third preset voltage is the voltage after the battery cells in the energy storage system are fully discharged and left stationary for a period of time. The voltage comparison module 306 includes: a third determination unit for determining whether the current average battery cell voltage is less than or equal to the third preset voltage; a seventh voltage setting unit for setting the third preset voltage as the final average battery cell voltage if the current average battery cell voltage is less than or equal to the third preset voltage; a fourth determination unit for determining whether the current average battery cell voltage is greater than or equal to the second preset voltage if the current average battery cell voltage is greater than the third preset voltage; an eighth voltage setting unit for setting the second preset voltage as the final average battery cell voltage if the current average battery cell voltage is greater than or equal to the second preset voltage; a ninth voltage setting unit for setting the current average battery cell voltage as the final average battery cell voltage if the current average battery cell voltage is less than the second preset voltage.

[0093] Optionally, the above SOE estimation module 308 includes: a first calculation unit for multiplying the current capacity by the final average battery cell voltage to obtain the current remaining energy of the energy storage system; a second calculation unit for multiplying the rated capacity by the full charge voltage to obtain the maximum storage energy of the energy storage system; a third calculation unit for dividing the current remaining energy of the energy storage system by the maximum storage energy of the energy storage system to obtain the SOE in the state of the energy storage system.

[0094] According to another aspect of the embodiments of the present application, an electronic device is provided, including: a processor, and a memory storing a program, the program including instructions that, when executed by the processor, cause the processor to execute the method for estimating the SOE of the energy storage system according to the embodiments of the present application.

[0095] According to another aspect of the embodiments of the present application, a non-transitory machine-readable medium storing computer instructions is provided, the computer instructions being used to cause a computer to execute the method for estimating the SOE of the energy storage system according to the embodiments of the present application.

[0096] According to another aspect of the embodiments of the present application, a computer program product is provided, including a computer program which, optionally, when executed by a processor of a computer, is used to cause the computer to execute the method for estimating the SOE of the energy storage system according to the embodiments of the present application.

[0097] Reference Figure 4, a block diagram of an electronic device that can be a server or a client as an embodiment of the present application will now be described. It is an example of a hardware device that can be applied to various aspects of the present application. The electronic device is intended to represent various forms of digital electronic computer devices, such as, laptop computers, desktop computers, workstations, personal digital assistants, servers, blade servers, mainframe computers, and other suitable computers. The electronic device can also represent various forms of mobile devices, such as, personal digital processors, cellular phones, smart phones, wearable devices, and other similar computing devices. The components shown herein, their connections and relationships, and their functions are merely examples and are not intended to limit the implementation of the present application described and / or claimed herein.

[0098] As Figure 4 shown, the electronic device includes a computing unit 401, which can perform various appropriate actions and processes according to a computer program stored in a read-only memory (ROM) 402 or a computer program loaded from a storage unit 408 into a random access memory (RAM) 403. In the RAM 403, various programs and data required for the operation of the electronic device can also be stored. The computing unit 401, the ROM 402, and the RAM 403 are connected to each other through a bus 404. An input / output (I / O) interface 405 is also connected to the bus 404.

[0099] Multiple components in the electronic device are connected to the I / O interface 405, including: an input unit 406, an output unit 407, a storage unit 408, and a communication unit 409. The input unit 406 can be any type of device that can input information into the electronic device. The input unit 406 can receive input digital or character information, and generate key signal inputs related to the user settings and / or function controls of the electronic device. The output unit 407 can be any type of device that can present information, and can include but is not limited to a display, a speaker, a video / audio output terminal, a vibrator, and / or a printer. The storage unit 408 can include but is not limited to magnetic disks and optical discs. The communication unit 409 allows the electronic device to exchange information / data with other devices through a computer network such as the Internet and / or various telecommunication networks, and can include but is not limited to a modem, a network card, an infrared communication device, and a wireless communication transceiver, such as a Bluetooth device, a WiFi device, a WiMax device, a cellular communication device, and / or the like.

[0100] The computing unit 401 can be various general-purpose and / or special-purpose processing components with processing and computing capabilities. Some examples of the computing unit 401 include, but are not limited to, a CPU, a graphics processing unit (GPU), various dedicated artificial intelligence (AI) computing units, various computing units running machine learning model algorithms, a digital signal processor (DSP), and any suitable processor, controller, microcontroller, etc. The computing unit 401 executes the various methods and processes described above. For example, in some embodiments, the method embodiments of the present application can be implemented as a computer program that is tangibly incorporated in a machine-readable medium, such as the storage unit 408. In some embodiments, part or all of the computer program can be loaded and / or installed onto the electronic device via the ROM 402 and / or the communication unit 409. In some embodiments, the computing unit 401 can be configured to execute the above-described method in any other suitable manner (e.g., by means of firmware).

[0101] The computer program for implementing the method of the embodiments of the present application can be written in any combination of one or more programming languages. These computer programs can be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, such that when the computer program is executed by the processor or controller, the functions / operations specified in the flowchart and / or block diagram are implemented. The computer program can be executed entirely on the machine, partially on the machine, as an independent software package partially on the machine and partially on a remote machine, or entirely on a remote machine or server.

[0102] In the context of the embodiments of the present application, the machine-readable medium can be a tangible medium that can contain or store a program for use by or in connection with an instruction execution system, apparatus, or device. The machine-readable medium can be a machine-readable signal medium or a machine-readable storage medium. The machine-readable signal medium can include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared system, apparatus, or device, or any suitable combination of the foregoing. More specific examples of the machine-readable storage medium would include an electrical connection based on one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disc read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0103] It should be noted that the term "including" and its variants used in the embodiments of this application are open-ended, that is, "including but not limited to". The term "based on" means "at least partially based on". The term "one embodiment" means "at least one embodiment"; the term "another embodiment" means "at least one additional embodiment"; the term "some embodiments" means "at least some embodiments". The modifications of "one" and "plural" mentioned in the embodiments of this application are illustrative rather than restrictive. Those skilled in the art should understand that unless clearly specified otherwise in the context, it should be understood as "one or more".

[0104] In the method embodiments provided by the embodiments of this application, the steps recorded can be executed in different orders and / or executed in parallel. In addition, the method embodiments may include additional steps and / or omit the steps shown. The protection scope of this application is not limited in this regard.

[0105] The term "embodiment" in this specification means that the specific features, structures or characteristics described in combination with the embodiment may be included in at least one embodiment of this application. The phrase appears in various positions in the specification does not necessarily mean the same embodiment, nor does it mean being independent or alternative to other embodiments and mutually exclusive. The various embodiments in this specification are described in a related manner, and the same or similar parts between the various embodiments are referred to each other. In particular, for device, equipment, and system embodiments, since they are basically similar to method embodiments, the description is relatively simple, and the relevant parts refer to the partial description of the method embodiments.

[0106] The above-described embodiments only represent several implementation manners of this application, and the description is relatively specific and detailed, but it should not be construed as a limitation on the scope of patent protection. It should be noted that for those of ordinary skill in the art, without departing from the concept of this application, several modifications and improvements can still be made, and these all belong to the protection scope of this application. Therefore, the protection scope of this application should be subject to the appended claims.

Claims

1. A method for estimating SOE of an energy storage system, characterized in that: include: Obtain the current capacity and rated capacity of the energy storage system; Determine the state of the energy storage system and set the full charge voltage of the energy storage system in the state; wherein the state of the energy storage system includes at least one of the following: charging state, discharging state and static state; Obtaining a current average cell voltage of the energy storage system, comparing the current average cell voltage with a voltage threshold value under a state of the energy storage system, and obtaining a final average cell voltage; Estimating the state of energy (SOE) according to the current capacity, the rated capacity, the full charge voltage, and the final average voltage of the battery cells to obtain the SOE of the energy storage system; Wherein, setting the full charge voltage of the energy storage system in the state includes: When the energy storage system is in the charging state, the first preset voltage is set to the full charge voltage; wherein the first preset voltage is the voltage when the battery cell in the energy storage system is fully charged; When the energy storage system is in the discharge state or the static state, the second preset voltage is set to the full charge voltage; wherein the second preset voltage is the voltage of the battery cell in the energy storage system after it is fully charged and static for a period of time; The SOE is estimated according to the current capacity, the rated capacity, the full charge voltage and the final average voltage of the battery cells to obtain the SOE of the energy storage system in the state, including: Multiplying the current capacity by the final average voltage of the battery cells to obtain the current remaining energy of the energy storage system; Multiplying the rated capacity by the full charge voltage to obtain the maximum storage energy of the energy storage system; The current remaining energy of the energy storage system is divided by the maximum storage energy of the energy storage system to obtain the SOE of the energy storage system in the state.

2. The method for estimating SOE of an energy storage system according to claim 1, characterized in that: When the state of the energy storage system is the charging state, the voltage threshold includes a first preset voltage, which is the voltage of a cell in the energy storage system when it is fully charged, and the current cell average voltage is compared with the voltage threshold in the state of the energy storage system to obtain a final cell average voltage, including: Determine whether the current average voltage of the battery cell is greater than or equal to the first preset voltage; If the current average cell voltage is greater than or equal to the first preset voltage, setting the first preset voltage as the final average cell voltage; If the current battery cell average voltage is less than the first preset voltage, the current battery cell average voltage is set as the final battery cell average voltage.

3. The method for estimating SOE of an energy storage system according to claim 1, characterized in that: When the energy storage system is in the discharge state, the voltage threshold includes a third preset voltage, and the third preset voltage is the voltage of the battery cells in the energy storage system after being discharged and standing for a period of time. The current battery cell average voltage is compared with the voltage threshold in the state of the energy storage system to obtain the final battery cell average voltage, including: Determine whether the current average voltage of the battery cell is less than or equal to the third preset voltage; If the current battery cell average voltage is less than or equal to the third preset voltage, setting the third preset voltage as the final battery cell average voltage; If the current battery cell average voltage is greater than the third preset voltage, the current battery cell average voltage is set as the final battery cell average voltage.

4. The method for estimating SOE of an energy storage system according to claim 1, characterized in that: When the state of the energy storage system is the static state, the voltage threshold includes a second preset voltage and a third preset voltage, the second preset voltage is the voltage of the battery cell in the energy storage system after being fully charged and standing for a period of time, and the third preset voltage is the voltage of the battery cell in the energy storage system after being fully discharged and standing for a period of time, and the current battery cell average voltage is compared with the voltage threshold in the state of the energy storage system to obtain the final battery cell average voltage, including: Determine whether the current average voltage of the battery cell is less than or equal to the third preset voltage; If the current battery cell average voltage is less than or equal to the third preset voltage, setting the third preset voltage as the final battery cell average voltage; If the current average voltage of the battery cells is greater than the third preset voltage, determining whether the current average voltage of the battery cells is greater than or equal to the second preset voltage; If the current battery cell average voltage is greater than or equal to the second preset voltage, setting the second preset voltage as the final battery cell average voltage; If the current battery cell average voltage is less than the second preset voltage, the current battery cell average voltage is set as the final battery cell average voltage.

5. A device for estimating SOE of an energy storage system, characterized in that: include: A capacity acquisition module is used to obtain the current capacity and rated capacity of the energy storage system; A voltage setting module, used to determine the state of the energy storage system and set the full charge voltage of the energy storage system in the state; wherein the state of the energy storage system includes at least one of the following: a charging state, a discharging state, and a static state; A voltage comparison module is used to obtain the current average voltage of the battery cells of the energy storage system, compare the current average voltage of the battery cells with the voltage threshold value under the state of the energy storage system, and obtain the final average voltage of the battery cells; An SOE estimation module is used to estimate the energy state SOE according to the current capacity, the rated capacity, the full charge voltage and the final average voltage of the battery cells to obtain the SOE of the energy storage system in the state; Wherein, the voltage setting module includes: A first voltage setting unit, used to set a first preset voltage to the full charge voltage when the energy storage system is in the charging state; wherein the first preset voltage is the voltage when the battery cell in the energy storage system is fully charged; A second voltage setting unit, used to set a second preset voltage to the full charge voltage when the energy storage system is in the discharge state or the static state; wherein the second preset voltage is the voltage of the battery cell in the energy storage system after it is fully charged and static for a period of time; The SOE estimation module comprises: A first calculation unit, configured to multiply the current capacity by the final average voltage of the battery cells to obtain the current remaining energy of the energy storage system; a second calculation unit, configured to multiply the rated capacity by the full charge voltage to obtain a maximum storage energy of the energy storage system; The third calculation unit is used to divide the current remaining energy of the energy storage system by the maximum storage energy of the energy storage system to obtain the SOE of the energy storage system in the state.

6. An electronic device comprising: A processor, and a memory storing a program, wherein the program includes instructions, and when the instructions are executed by the processor, the processor executes the method for estimating the SOE of an energy storage system according to any one of claims 1 to 4.

7. A non-transitory machine-readable medium storing computer instructions, characterized in that: The computer instructions are used to enable the computer to execute the method for estimating the SOE of an energy storage system according to any one of claims 1 to 4.

8. A computer program product, comprising a computer program, characterized in that When the computer program is executed by a processor of a computer, it is used to make the computer execute the method for estimating SOE of an energy storage system according to any one of claims 1 to 4.

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