Battery cluster SOC estimation method

Abstract

The invention relates to the technical field of battery SOC estimation, and discloses a battery cluster SOC estimation method, which comprises the following steps: calibrating the rated capacity of a battery cluster through capacity calibration to ensure that a BMS (Battery Management System) can obtain the actual capacity of the battery cluster and optimize the precision error of the SOC caused by battery aging, and then calibrating the SOC through standing OCV-SOC of the battery cluster. The condition that the specific self-power consumption cannot be predicted under the condition that the battery cluster is not used for a long time is avoided, the standing calibration SOC is obtained according to the open-circuit voltage state of the battery cell, the consumed electric quantity is calibrated back in the charging and discharging process, it is guaranteed that the SOC does not change under the standing condition, and therefore estimation of the SOC of the battery cluster is accurately achieved, and the battery cluster SOC estimation efficiency is improved. And influence on customer use is avoided.

Description

Technical Field

[0001] The present invention relates to the technical field of battery SOC estimation, and in particular to a battery cluster SOC estimation method. Background Art

[0002] SOC (State of Charge) refers to the ratio between the current remaining capacity of the battery and its rated capacity. As a core component of the BMS (Battery Monitoring and Management System), SOC is not only a key element of the energy storage system, but also a decisive indicator to ensure the stable operation of the energy storage power station. It plays a vital role in improving the battery life and ensuring the safety of use.

[0003] However, as a key parameter inside the battery, SOC is difficult to measure directly and accurately, and can only be approximated by various estimation methods.

[0004] At present, the industry generally adopts a method that combines the ampere-hour integration method and the open circuit voltage method to estimate SOC. Among them, the ampere-hour integration method is prone to introduce errors in the current measurement link due to the limitations of sampling accuracy and sampling interval. These errors will continue to accumulate over time, resulting in inaccurate SOC estimation results. In addition, as the battery is used for a longer time, the aging of the battery will cause its capacity to gradually decay and the internal resistance to continue to increase, making the SOC estimation process more complicated and challenging.

[0005] Therefore, it is necessary to conduct in-depth research and improvement on these problems existing in the prior art.

[0006] The above information is presented as background information only to assist with understanding the present disclosure and no determination or admission is made as to whether any of the above may be used as prior art with respect to the present disclosure. Summary of the invention

[0007] The present invention provides a battery cluster SOC estimation method to solve the problems existing in the prior art.

[0008] To achieve the above object, the present invention provides the following technical solutions:

[0009] In a first aspect, the present invention provides a battery cluster SOC estimation method, the method comprising:

[0010] S1. Calibrate the rated capacity of the battery cluster;

[0011] S2, determining whether the battery cluster is in a static state; if so, executing S3, if not, executing S4;

[0012] S3, obtaining the average cell voltage and static display SOC of the battery cluster, and searching for a calibration SOC corresponding to the average cell voltage of the battery cluster from a set OCV-SOC data table, and correcting the static display SOC of the battery cluster to the found calibration SOC;

[0013] S4, determining whether the battery cluster is in a charging state; if so, executing S5, if not, executing S12;

[0014] S5, when the battery cluster is in a charging state, determining whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in an OCV-SOC data table when the battery cluster is in a static state; if so, executing S6, if not, executing S9;

[0015] S6, determining whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference=calibrated SOC of the battery cluster-static display SOC of the battery cluster; if yes, executing S7, if no, executing S8;

[0016] S7. Calculate the SOC of the battery cluster after calibration according to the following formula:

[0017] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2);

[0018] S8. Calculate the SOC of the battery cluster after calibration according to the following formula:

[0019] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster;

[0020] S9, determining whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the static display SOC of the battery cluster - the calibrated SOC of the battery cluster; if so, executing S10, if not, executing S11;

[0021] S10, calculating the SOC of the battery cluster after calibration according to the following formula:

[0022] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5);

[0023] S11, calculating the SOC of the battery cluster after calibration according to the following formula:

[0024] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster;

[0025] S12, determining that the battery cluster is in a discharging state, and when the battery cluster is in the discharging state, determining whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in an OCV-SOC data table when the battery cluster is in a static state; if so, executing S13, if not, executing S16;

[0026] S13, determining whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the calibrated SOC of the battery cluster - the static display SOC of the battery cluster; if yes, executing S14, if no, executing S15;

[0027] S14, calculating the SOC of the battery cluster after calibration according to the following formula:

[0028] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5);

[0029] S15, calculating the SOC of the battery cluster after calibration according to the following formula:

[0030] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster;

[0031] S16, determining whether the difference between the static displayed SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference=static displayed SOC of the battery cluster-calibrated SOC of the battery cluster; if yes, executing S17, if no, executing S18;

[0032] S17, calculating the SOC of the battery cluster after calibration according to the following formula:

[0033] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2);

[0034] S18, calculating the SOC of the battery cluster after calibration according to the following formula:

[0035] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0036] Furthermore, in the battery cluster SOC estimation method, S1 includes:

[0037] S101, after fully charging the battery cluster, recording the cumulative charging capacity and the cumulative discharging capacity of the battery cluster when charging stops;

[0038] S102, after the battery cluster is fully discharged within a second set time, recording the cumulative charging capacity of the battery cluster when discharge stops and the cumulative discharging capacity of the battery cluster when discharge stops;

[0039] S103, calculating the actual capacity of the battery cluster according to the cumulative charging capacity when charging stops, the cumulative discharging capacity when charging stops, the cumulative charging capacity when discharging stops, and the cumulative discharging capacity when discharging stops, and correcting the rated capacity of the battery cluster to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0040] Furthermore, in the battery cluster SOC estimation method, the calculation formula for the actual capacity of the battery cluster is:

[0041] The actual capacity of the battery cluster=(cumulative discharge capacity when discharge stops−cumulative discharge capacity when charge stops)−(cumulative charge capacity when discharge stops−cumulative charge capacity when charge stops).

[0042] Furthermore, in the battery cluster SOC estimation method, before S3, the method further includes:

[0043] S2.5 determines whether the static time of the battery cluster is greater than the first set time; if so, execute S3, if not, continue to execute S2.5.

[0044] Furthermore, in the battery cluster SOC estimation method, S3 is specifically:

[0045] The average cell voltage and static display SOC of the battery cluster are obtained, and a calibration SOC corresponding to the average cell voltage of the battery cluster is searched through a binary search from a set OCV-SOC data table, and the static display SOC of the battery cluster is corrected to the searched calibration SOC.

[0046] Furthermore, in the battery cluster SOC estimation method, the calculation formula of the real-time SOC of the battery cluster is:

[0047] The real-time SOC of the battery cluster=(the remaining capacity of the battery cluster÷the actual capacity of the battery cluster)*100%.

[0048] Furthermore, in the battery cluster SOC estimation method, the method further includes:

[0049] S21, during the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, obtaining the maximum single cell voltage of the battery cluster and the real-time SOC of the battery cluster;

[0050] S22, searching a set OCV-SOC data table for a dynamic calibration SOC of the battery cluster corresponding to the maximum cell voltage of the battery cluster;

[0051] S23, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S24, if not, executing S27;

[0052] S24, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S25, if not, executing S26;

[0053] S25, calculating the SOC of the battery cluster after calibration according to the following formula:

[0054] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2);

[0055] S26, calculating the SOC of the battery cluster after calibration according to the following formula:

[0056] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4);

[0057] S27, determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S28, if not, executing S211;

[0058] S28, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S29, if not, executing S210;

[0059] S29, calculating the SOC of the battery cluster after calibration according to the following formula:

[0060] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5);

[0061] S210, calculating the SOC of the battery cluster after calibration according to the following formula:

[0062] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25);

[0063] S211, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula:

[0064] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0065] Furthermore, in the battery cluster SOC estimation method, the method further includes:

[0066] S31, during the discharge process of the battery cluster, when the real-time SOC of the battery cluster is less than 25%, obtaining the minimum cell voltage of the battery cluster and the real-time SOC of the battery cluster;

[0067] S32, searching a set OCV-SOC data table for a dynamic calibration SOC of the battery cluster corresponding to a minimum cell voltage of the battery cluster;

[0068] S33, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S34, if not, executing S37;

[0069] S34, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S35, if not, executing S36;

[0070] S35, calculating the SOC of the battery cluster after calibration according to the following formula:

[0071] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5);

[0072] S36, calculating the SOC of the battery cluster after calibration according to the following formula:

[0073] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25);

[0074] S37, determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S38, if not, executing S311;

[0075] S38, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S39, if not, executing S310;

[0076] S39, calculating the SOC of the battery cluster after calibration according to the following formula:

[0077] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2);

[0078] S310, calculating the SOC of the battery cluster after calibration according to the following formula:

[0079] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4);

[0080] S311, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula:

[0081] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0082] In a second aspect, the present invention provides a computer device, comprising a memory and a processor, wherein the memory stores a computer program, and when the processor executes the computer program, the battery cluster SOC estimation method provided in the first aspect is implemented.

[0083] In a third aspect, the present invention provides a computer-readable storage medium having computer-executable instructions stored thereon, wherein the computer-executable instructions are executed by a computer processor to implement the battery cluster SOC estimation method provided in the first aspect above.

[0084] Compared with the prior art, the present invention has the following beneficial effects:

[0085] The present invention provides a battery cluster SOC estimation method, which first calibrates the rated capacity of the battery cluster through capacity calibration to ensure that the BMS system can obtain the actual capacity of the battery cluster and optimize the accuracy error of the SOC due to battery aging, and then calibrates the SOC through the static OCV-SOC of the battery cluster to avoid the inability to predict the specific size of the self-consumption power of the battery cluster when it is not used for a long time. The static calibration SOC is obtained according to the open circuit voltage state of the battery cell, and the lost power is calibrated back during the charging and discharging process to ensure that the SOC does not change when it is static, thereby accurately realizing the estimation of the SOC of the battery cluster and avoiding affecting the use of customers.

[0086] The present invention has other features and advantages, which will be apparent from or will be described in detail in the accompanying drawings and the following detailed description incorporated herein, which together serve to explain the specific principles of the invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0087] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0088] Figure 1 It is a flowchart of a battery cluster SOC estimation method provided in the first embodiment of the present invention;

[0089] Figure 2 It is a flowchart of a battery cluster SOC estimation method provided in the first embodiment of the present invention;

[0090] Figure 3 It is a detailed flow chart of S1 mentioned in the first embodiment of the present invention;

[0091] Figure 4 It is a structural diagram of a computer device provided in Embodiment 2 of the present invention. DETAILED DESCRIPTION

[0092] In order to explain in detail the possible application scenarios, technical principles, specific schemes that can be implemented, and the purposes and effects that can be achieved, the following is a detailed description of the specific embodiments listed in conjunction with the accompanying drawings. The embodiments described herein are only used to more clearly illustrate the technical solutions of the present application, and are therefore only used as examples, and cannot be used to limit the scope of protection of the present application.

[0093] Reference to "embodiment" herein means that the specific features, structures or characteristics described in conjunction with the embodiment may be included in at least one embodiment of the present application. The term "embodiment" appearing in various places in the specification does not necessarily refer to the same embodiment, nor does it particularly limit its independence or association with other embodiments. In principle, in the present application, as long as there is no technical contradiction or conflict, the various technical features mentioned in the embodiments can be combined in any way to form a corresponding implementable technical solution.

[0094] Unless otherwise defined, the technical terms used in this document have the same meanings as those generally understood by those skilled in the art to which this application belongs; the use of relevant terms in this document is only for describing specific embodiments and is not intended to limit this application.

[0095] In the description of this application, the term "and / or" is an expression used to describe the logical relationship between objects, indicating that three relationships may exist, for example, A and / or B, which means: A exists, B exists, and A and B exist at the same time. In addition, the character " / " in this article generally indicates that the objects before and after are in an "or" logical relationship.

[0096] In the present application, terms such as “first” and “second” are merely used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship of quantity, priority or sequence between these entities or operations.

[0097] Without further limitations, in this application, the words "include", "comprises", "has" or other similar expressions used in the sentences are intended to cover non-exclusive inclusion. These expressions do not exclude the presence of additional elements in the process, method or product including the elements, so that the process, method or product including a series of elements may include not only those limited elements, but also other elements not explicitly listed, or also include elements inherent to such process, method or product.

[0098] In this application, expressions such as "greater than", "less than", "exceed" and the like are understood to exclude the number itself; expressions such as "above", "below", "within" and the like are understood to include the number itself. In addition, in the description of the embodiments of this application, "multiple" means more than two (including two), and similar expressions related to "multiple" are also understood in this way, such as "multiple groups", "multiple times", etc., unless otherwise clearly and specifically limited.

[0099] In the description of the embodiments of the present application, space-related expressions used, such as "center", "longitudinal", "lateral", "length", "width", "thickness", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "vertical", "top", "bottom", "inside", "outside", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc., indicate the orientation or position relationship based on the orientation or position relationship shown in the specific embodiments or drawings, and are only for the convenience of describing the specific embodiments of the present application or facilitating the reader's understanding, and do not indicate or imply that the referred device or component must have a specific position, a specific orientation, or be constructed or operated in a specific orientation, and therefore cannot be understood as a limitation on the embodiments of the present application.

[0100] Unless otherwise expressly specified or limited, in the description of the embodiments of the present application, the terms such as "install", "connect", "connect", "fix", "set", etc. used should be understood in a broad sense. For example, the "connection" can be a fixed connection, a detachable connection, or an integrated setting; it can be a mechanical connection, an electrical connection, or a communication connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium; it can be the internal connection of two elements or the interaction relationship between two elements. For technicians in the technical field to which the present application belongs, the specific meanings of the above terms in the embodiments of the present application can be understood according to the specific circumstances.

[0101] Embodiment 1

[0102] In view of the defects of the above-mentioned prior art, the applicant, based on many years of rich practical experience and professional knowledge in this field, and in conjunction with the application of theory, actively conducts research and innovation in the hope of creating a technology that can solve the defects of the prior art. After continuous research and design, and after repeated trial production and improvement, the present invention with real practical value was finally created.

[0103] Please refer to Figure 1-2 , a flow chart of a battery cluster SOC estimation method provided in the first embodiment of the present invention, the method is applicable to the scenario of estimating the SOC of a battery cluster. The method specifically comprises the following steps:

[0104] S1. Calibrate the rated capacity of the battery cluster.

[0105] It should be noted that this step is to ensure that the rated capacity data of the battery cluster is accurate, because the actual capacity of the battery will change during use due to factors such as aging and temperature changes. Through calibration, the rated capacity data in the BMS (battery management system) can be updated to provide a basis for subsequent SOC estimation.

[0106] S2, determining whether the battery cluster is in a static state; if so, executing S3, if not, executing S4.

[0107] It should be noted that the static state refers to the battery cluster not being charged or discharged and being in a static state. This step is to determine whether the OCV (open circuit voltage) method can be used for SOC estimation, because the OCV method is most accurate after the battery has been static for a period of time.

[0108] S3, obtaining the average cell voltage and static display SOC of the battery cluster, searching for a calibration SOC corresponding to the average cell voltage of the battery cluster from a set OCV-SOC data table, and correcting the static display SOC of the battery cluster to the found calibration SOC.

[0109] It should be noted that when the battery cluster is in a static state, the average cell voltage is calculated by measuring the voltage of each battery cell in the battery cluster. Then, the corresponding calibration SOC is found in the pre-set OCV-SOC data table according to the voltage value. This calibration SOC will be used to correct the static display SOC of the battery cluster to improve accuracy.

[0110] S4, determining whether the battery cluster is in a charging state; if so, executing S5, if not, executing S12.

[0111] It should be noted that if the battery cluster is not in a static state, it means that it is in a charging and discharging state. This step is to distinguish whether the battery cluster is in a charging or discharging state so as to adopt different SOC estimation strategies.

[0112] S5. When the battery cluster is in a charging state, determine whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in the OCV-SOC data table when the battery cluster is in a static state; if so, execute S6, if not, execute S9.

[0113] It should be noted that this step is to determine the relationship between the calibration SOC and the static display SOC to determine whether further calibration is required.

[0114] S6, determine whether the difference between the real-time SOC of the battery cluster and the static displayed SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference=calibrated SOC of the battery cluster-static displayed SOC of the battery cluster; if yes, execute S7, if not, execute S8.

[0115] S7. Calculate the SOC of the battery cluster after calibration according to the following formula:

[0116] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the ampere-hour integrated amount of the battery cluster*2).

[0117] S8. Calculate the SOC of the battery cluster after calibration according to the following formula:

[0118] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0119] It should be noted that in S6-S8, when the battery cluster is in a charging state, if the calibrated SOC is greater than or equal to the static display SOC, and the difference between the real-time SOC and the static display SOC is within a certain range (∆SOC difference * 2), the enhanced ampere-hour integration method (multiplied by 2) is used for SOC calibration to more quickly reflect the SOC changes during the charging process.

[0120] S9, determine whether the difference between the real-time SOC of the battery cluster and the static displayed SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the static displayed SOC of the battery cluster - the calibrated SOC of the battery cluster; if so, execute S10, if not, execute S11.

[0121] S10, calculating the SOC of the battery cluster after calibration according to the following formula:

[0122] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the integrated ampere-hour amount of the battery cluster*0.5).

[0123] S11, calculating the SOC of the battery cluster after calibration according to the following formula:

[0124] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0125] It should be noted that in S9-S11, when the battery cluster is in a charging state, if the calibration SOC is less than the static display SOC, or the difference between the real-time SOC and the static display SOC exceeds a certain range, the standard ampere-hour integration method is used to calibrate the SOC.

[0126] S12, determining that the battery cluster is in a discharging state, and when the battery cluster is in the discharging state, determining whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in an OCV-SOC data table when the battery cluster is in a static state; if so, executing S13, if not, executing S16.

[0127] S13, determining whether the difference between the static displayed SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the calibrated SOC of the battery cluster - the static displayed SOC of the battery cluster; if so, executing S14, if not, executing S15.

[0128] S14, calculating the SOC of the battery cluster after calibration according to the following formula:

[0129] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the integrated ampere-hour amount of the battery cluster*0.5).

[0130] S15, calculating the SOC of the battery cluster after calibration according to the following formula:

[0131] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0132] S16, determine whether the difference between the static displayed SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference = static displayed SOC of the battery cluster - calibrated SOC of the battery cluster; if yes, execute S17, if not, execute S18.

[0133] S17, calculating the SOC of the battery cluster after calibration according to the following formula:

[0134] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the ampere-hour integrated amount of the battery cluster*2).

[0135] S18, calculating the SOC of the battery cluster after calibration according to the following formula:

[0136] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0137] It should be noted that in S12-S18, this part of the logic is similar to the charging state, but it deals with the discharge situation. It also includes judging the relationship between the calibrated SOC and the static display SOC, the difference between the real-time SOC and the static display SOC, and using the enhanced or standard ampere-hour integration method to calibrate the SOC.

[0138] Specifically, S12: Determine whether the battery cluster is in a discharging state.

[0139] S13-S15: If the calibrated SOC is greater than or equal to the static display SOC, and the difference between the static display SOC and the real-time SOC is within a certain range (∆SOC difference), the weakened ampere-hour integration method (multiplied by 0.5) is used to calibrate the SOC to reflect the SOC change during the discharge process, but the calibration speed is slowed down to avoid over-calibration.

[0140] S16-S18: If the calibrated SOC is less than the static display SOC, or the difference between the static display SOC and the real-time SOC exceeds a certain range (∆SOC difference * 2), the standard ampere-hour integration method is used to calibrate the SOC.

[0141] The battery cluster SOC estimation method of the embodiment of the present invention combines the OCV method and the ampere-hour integration method, and takes into account the static, charging and discharging states of the battery cluster, as well as the relationship between the calibration SOC and the static display SOC, to achieve accurate estimation of the battery cluster SOC. This method not only improves the accuracy of SOC estimation, but also enhances the reliability and stability of the battery management system.

[0142] Please refer to Figure 3 In one implementation of this embodiment, S1 is further refined into the following three specific steps to achieve more accurate capacity calibration:

[0143] S101 . After fully charging a battery cluster, record the cumulative charging capacity and the cumulative discharging capacity of the battery cluster when charging stops.

[0144] It should be noted that, first, the battery cluster is fully charged, that is, charged to its maximum capacity. When charging stops, the cumulative charge capacity at this time (that is, the total amount of electricity charged from the first charge to this charge) and the cumulative discharge capacity when charging stops (the total amount of electricity discharged by the battery cluster before this charge, which is used to consider the historical use of the battery) are recorded.

[0145] S102 , after the battery cluster is fully discharged within a second set time, the cumulative charging capacity when discharge stops and the cumulative discharging capacity when discharge stops of the battery cluster are recorded.

[0146] It should be noted that, next, the battery cluster is fully discharged within a second set time, which is to ensure that the battery cluster has enough time to be fully discharged and to avoid damage to the battery due to excessive discharge, for example, eight hours.

[0147] When the discharge stops, the cumulative charge capacity at this time (the total amount of electricity that has been charged into the battery cluster before this discharge, taking into account the possible charging history) and the cumulative discharge capacity when the discharge stops (that is, the total amount of electricity discharged from the first discharge to this discharge) are also recorded.

[0148] S103, calculating the actual capacity of the battery cluster according to the cumulative charging capacity when charging stops, the cumulative discharging capacity when charging stops, the cumulative charging capacity when discharging stops, and the cumulative discharging capacity when discharging stops, and correcting the rated capacity of the battery cluster to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0149] It should be noted that the actual capacity of the battery cluster is calculated by a specific calculation method using the cumulative charge capacity and the cumulative discharge capacity recorded in steps S101 and S102.

[0150] This actual capacity reflects the real energy storage capability of the battery cluster in its current state.

[0151] Finally, the rated capacity of the battery cluster is corrected to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

[0152] In one implementation of this embodiment, the calculation formula for the actual capacity of the battery cluster is:

[0153] The actual capacity of the battery cluster=(cumulative discharge capacity when discharge stops−cumulative discharge capacity when charge stops)−(cumulative charge capacity when discharge stops−cumulative charge capacity when charge stops).

[0154] It should be noted that this formula is derived based on the battery's energy conservation principle and the change in charge during the charging and discharging process.

[0155] Substituting the four values ​​recorded above into the formula, we can get the actual capacity of the battery cluster. This value reflects the actual energy storage capacity of the battery cluster in its current state and is an important basis for subsequent SOC estimation.

[0156] It should be noted that this formula assumes that there is no other energy loss during the charging and discharging process (such as battery self-discharge, heat loss, etc.), or that these losses have been taken into account. In practical applications, the formula may need to be corrected or adjusted according to specific circumstances.

[0157] In addition, this formula also emphasizes that when performing capacity calibration, the charge and discharge history of the battery cluster needs to be accurately recorded to ensure the accuracy of the calculation. This is usually achieved through a BMS (battery management system), which can monitor and record the charge and discharge status of the battery cluster in real time.

[0158] In one implementation of this embodiment, before S3, the method further includes:

[0159] S2.5 determines whether the static time of the battery cluster is greater than the first set time; if so, execute S3, if not, continue to execute S2.5.

[0160] It should be noted that the first set time is a threshold value used to ensure that the battery cluster has been in a static state for a sufficiently long time so that its open circuit voltage can stably and accurately reflect the SOC of the battery.

[0161] The OCV method relies on the open circuit voltage of the battery cluster at rest to estimate the SOC. If the rest time of the battery cluster is not long enough, the open circuit voltage may not be stable, resulting in inaccurate SOC estimation. By adding step S2.5, it can be ensured that the battery cluster is in a stable state before executing the OCV method.

[0162] By ensuring the stability of the battery cluster at rest, the accuracy and reliability of SOC estimation can be improved, which is very important for the performance of the battery management system and the long-term use of the battery cluster.

[0163] In summary, the S2.5 step is added to ensure that the battery cluster is in a stable static state before executing the OCV method, thereby improving the accuracy and reliability of SOC estimation.

[0164] In one implementation of this embodiment, S3 is specifically:

[0165] The average cell voltage and static display SOC of the battery cluster are obtained, and a calibration SOC corresponding to the average cell voltage of the battery cluster is searched through a binary search from a set OCV-SOC data table, and the static display SOC of the battery cluster is corrected to the searched calibration SOC.

[0166] It should be noted that the binary search algorithm is an efficient search algorithm that can quickly find the position of the target value in an ordered array.

[0167] The specific process of binary search:

[0168] First, determine the minimum and maximum OCV values ​​in the OCV-SOC data table, as well as the corresponding minimum and maximum SOC values.

[0169] Then, the intermediate OCV value and the corresponding intermediate SOC value are calculated.

[0170] Compare the average cell voltage of the battery cluster with the median OCV value:

[0171] If the average cell voltage is less than the middle OCV value, continue searching in the left half of the data table;

[0172] If the average cell voltage is greater than the middle OCV value, continue searching in the right half of the data table;

[0173] If the average cell voltage is equal to the middle OCV value (or very close), then the corresponding SOC value is found.

[0174] The above process is repeated until the OCV value closest to the average cell voltage of the battery cluster and its corresponding SOC value are found.

[0175] In one implementation of this embodiment, the real-time SOC of the battery cluster is calculated by ampere-hour integration, and current integration is performed every 100 ms. The specific calculation formula is:

[0176] The real-time SOC of the battery cluster=(the remaining capacity of the battery cluster÷the actual capacity of the battery cluster)*100%.

[0177] It should be noted that in this embodiment, the real-time SOC of the battery cluster is calculated by ampere-hour integration. The ampere-hour integration method is a commonly used battery SOC estimation method. It estimates the remaining capacity of the battery based on the current integration during the battery charging and discharging process, thereby obtaining the SOC value, providing reliable data support for the decision-making of the battery management system. At the same time, combined with regular capacity calibration and SOC correction steps, the accuracy and reliability of SOC estimation can be further improved.

[0178] In order to further improve the accuracy of SOC estimation, the embodiment of the present invention also considers the calibration of the SOC terminal during the charging and discharging process, that is, when the real-time SOC of the battery cluster is greater than 75% or less than 25%, the battery cluster dynamic calibration SOC is confirmed by the maximum or minimum single cell voltage and SOC and the preset dynamic SOC-OCV data table, so that the real-time SOC of the battery cluster is accelerated or decelerated to catch up with the dynamic calibration SOC of the battery cluster, thereby reducing the SOC error.

[0179] Specifically, in one implementation of this embodiment, with respect to the charging of the battery cluster, the method further includes:

[0180] S21 . During the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, obtaining the maximum single cell voltage of the battery cluster and the real-time SOC of the battery cluster.

[0181] S22 . Searching for a dynamic calibration SOC of the battery cluster corresponding to the maximum cell voltage of the battery cluster from a set OCV-SOC data table.

[0182] S23, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S24, if not, executing S27.

[0183] S24, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S25, if not, executing S26.

[0184] S25, calculating the SOC of the battery cluster after calibration according to the following formula:

[0185] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the ampere-hour integrated amount of the battery cluster*2).

[0186] S26, calculating the SOC of the battery cluster after calibration according to the following formula:

[0187] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the ampere-hour integrated amount of the battery cluster*4).

[0188] S27 , determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S28 , if not, executing S211 .

[0189] S28, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S29, if not, executing S210.

[0190] S29, calculating the SOC of the battery cluster after calibration according to the following formula:

[0191] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the integrated ampere-hour amount of the battery cluster*0.5).

[0192] S210, calculating the SOC of the battery cluster after calibration according to the following formula:

[0193] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+(the integrated ampere-hour amount of the battery cluster*0.25).

[0194] S211, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula:

[0195] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0196] It should be noted that this method achieves dynamic calibration of the battery cluster SOC by comparing the real-time SOC with the dynamically calibrated SOC obtained based on the maximum cell voltage, and adjusting the calculation coefficient of the ampere-hour integral according to the difference. This method helps to further improve the accuracy of SOC estimation, especially in the terminal area of ​​the charging process, helps to reduce SOC errors, improve the performance of the battery management system and the long-term reliability of the battery cluster.

[0197] In one implementation of this embodiment, in view of the discharge of the battery cluster, the method further includes:

[0198] S31, during the discharge process of the battery cluster, when the real-time SOC of the battery cluster is less than 25%, obtaining the minimum cell voltage of the battery cluster and the real-time SOC of the battery cluster;

[0199] S32, searching a set OCV-SOC data table for a dynamic calibration SOC of the battery cluster corresponding to a minimum cell voltage of the battery cluster;

[0200] S33, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S34, if not, executing S37;

[0201] S34, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S35, if not, executing S36;

[0202] S35, calculating the SOC of the battery cluster after calibration according to the following formula:

[0203] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5);

[0204] S36, calculating the SOC of the battery cluster after calibration according to the following formula:

[0205] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25);

[0206] S37, determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S38, if not, executing S311;

[0207] S38, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S39, if not, executing S310;

[0208] S39, calculating the SOC of the battery cluster after calibration according to the following formula:

[0209] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2);

[0210] S310, calculating the SOC of the battery cluster after calibration according to the following formula:

[0211] The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4);

[0212] S311, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula:

[0213] The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

[0214] It should be noted that this method achieves dynamic calibration of the battery cluster SOC by comparing the real-time SOC with the dynamically calibrated SOC obtained based on the minimum cell voltage, and adjusting the calculation coefficient of the ampere-hour integral according to the difference. This method helps to further improve the accuracy of SOC estimation, especially in the terminal area of ​​the discharge process, helps to reduce SOC errors, improve the performance of the battery management system and the long-term reliability of the battery cluster.

[0215] Although the terms such as battery cluster, rated capacity, calibration, etc. are used more frequently in this application, the possibility of using other terms is not excluded. These terms are used only to more conveniently describe and explain the essence of the present invention; interpreting them as any additional restrictions is contrary to the spirit of the present invention.

[0216] The embodiment of the present invention provides a battery cluster SOC estimation method, the first step of which is to implement a capacity calibration process to ensure that the rated capacity of the battery pack is accurately adjusted. This process is crucial for the battery management system (BMS) because it enables the BMS system to accurately obtain the actual capacity of the battery pack and further optimize the SOC estimation accuracy error caused by battery aging.

[0217] Next, this method uses the relationship between the open circuit voltage OCV and SOC of the battery pack under static conditions to calibrate the SOC. This step is particularly critical, as it can effectively address the problem of difficult-to-predict self-consumption of power that may occur after a long period of idleness. Specifically, this method accurately obtains the calibrated SOC value under static conditions based on the open circuit voltage state of the battery cell. In addition, during the battery's charge and discharge cycle, this method also takes into account the loss of power and performs corresponding calibration compensation to ensure that the SOC value remains stable even under static conditions.

[0218] Finally, by performing SOC-OCV dynamic calibration at the end of the battery cluster charge and discharge, the preset dynamic SOC-OCV table is looked up according to the maximum or minimum single cell voltage and the battery cluster power to obtain the dynamic calibration SOC, and the SOC of the battery cluster is calibrated. This can avoid the battery cluster SOC from jumping at the end of charge and discharge, and further improve the accuracy of the battery cluster SOC estimation.

[0219] This series of sophisticated operations together ensures the high accuracy of the battery pack SOC estimation, thereby minimizing the inconvenience and impact that may be caused to customers due to SOC estimation deviation. In summary, the battery pack SOC estimation method provided by the present invention not only improves the estimation accuracy, but also enhances the overall efficiency and reliability of the battery management system.

[0220] Embodiment 2

[0221] Figure 4 A schematic diagram of the structure of a computer device provided in Embodiment 2 of the present invention. Figure 4 A block diagram of an exemplary computer device 12 suitable for use in implementing embodiments of the present invention is shown. Figure 4 The computer device 12 shown is only an example and should not bring any limitation to the functions and scope of use of the embodiments of the present invention.

[0222] like Figure 4 As shown, the computer device 12 is in the form of a general-purpose computing device. The components of the computer device 12 may include, but are not limited to: one or more processors or processing units 16, a system memory 28, and a bus 18 that connects various system components (including the system memory 28 and the processing unit 16).

[0223] Bus 18 represents one or more of several types of bus structures, including a memory bus or memory controller, a peripheral bus, an accelerated graphics port, a processor or a local bus using any of a variety of bus architectures. By way of example, these architectures include, but are not limited to, an Industry Standard Architecture (ISA) bus, a Micro Channel Architecture (MAC) bus, an Enhanced ISA bus, a Video Electronics Standards Association (VESA) local bus, and a Peripheral Component Interconnect (PCI) bus.

[0224] The computer device 12 typically includes a variety of computer system readable media. These media can be any available media that can be accessed by the computer device 12, including volatile and non-volatile media, removable and non-removable media.

[0225] The system memory 28 may include computer system readable media in the form of volatile memory, such as random access memory (RAM) 30 and / or cache memory 32. The computer device 12 may further include other removable / non-removable, volatile / non-volatile computer system storage media. By way of example only, the storage system 34 may be used to read and write non-removable, non-volatile magnetic media ( Figure 4 not shown, usually called a "hard drive"). Although Figure 4 Not shown in the figure, a disk drive for reading and writing to a removable non-volatile disk (e.g., a "floppy disk"), and an optical disk drive for reading and writing to a removable non-volatile optical disk (e.g., a CD-ROM, a DVD-ROM, or other optical media) may be provided. In these cases, each drive may be connected to the bus 18 via one or more data medium interfaces. The memory 28 may include at least one program product having a set (e.g., at least one) of program modules that are configured to perform the functions of the various embodiments of the present invention.

[0226] A program / utility 40 having a set (at least one) of program modules 42 may be stored, for example, in the memory 28, such program modules 42 including but not limited to an operating system, one or more application programs, other program modules, and program data, each of which or some combination may include an implementation of a network environment. The program modules 42 generally perform the functions and / or methods of the embodiments described herein.

[0227] The computer device 12 may also communicate with one or more external devices 14 (e.g., keyboards, pointing devices, displays 24, etc.), one or more devices that enable a user to interact with the computer device 12, and / or any device that enables the computer device 12 to communicate with one or more other computing devices (e.g., a network card, a modem, etc.). Such communication may be performed via an input / output (I / O) interface 22. In addition, the computer device 12 may also communicate with one or more networks (e.g., a local area network (LAN), a wide area network (WAN), and / or a public network, such as the Internet) via a network adapter 20. As shown, the network adapter 20 communicates with the other modules of the computer device 12 via a bus 18. It should be understood that although Figure 4 Not shown, other hardware and / or software modules may be used in conjunction with computer device 12, including but not limited to microcode, device drivers, redundant processing units, external disk drive arrays, RAID systems, tape drives, and data backup storage systems.

[0228] The processing unit 16 executes various functional applications and data processing by running the programs stored in the system memory 28 , such as implementing the battery cluster SOC estimation method provided in the embodiment of the present invention.

[0229] Embodiment 3

[0230] Embodiment 3 of the present invention provides a computer-readable storage medium on which computer-executable instructions are stored. When the instructions are executed by a processor, the battery cluster SOC estimation method provided in all the embodiments of the present application is implemented.

[0231] Any combination of one or more computer-readable media may be used. A computer-readable medium may be a computer-readable signal medium or a computer-readable storage medium. A computer-readable storage medium may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any combination thereof. More specific examples (a non-exhaustive list) of computer-readable storage media include: an electrical connection with 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 disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination thereof. In this document, a computer-readable storage medium may be any tangible medium containing or storing a program that may be used by or in conjunction with an instruction execution system, device, or device.

[0232] Computer-readable signal media may include data signals propagated in baseband or as part of a carrier wave, which carry computer-readable program code. Such propagated data signals may take a variety of forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination of the above. Computer-readable signal media may also be any computer-readable medium other than a computer-readable storage medium, which may send, propagate, or transmit a program for use by or in conjunction with an instruction execution system, apparatus, or device.

[0233] Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to wireless, wireline, optical fiber cable, RF, etc., or any suitable combination of the foregoing.

[0234] Computer program code for performing the operations of the present invention may be written in one or more programming languages ​​or a combination thereof, including object-oriented programming languages ​​such as Java, Smalltalk, C++, and conventional procedural programming languages ​​such as "C" or similar programming languages. The program code may be executed entirely on the user's computer, partially on the user's computer, as a separate software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In the case of a remote computer, the remote computer may be connected to the user's computer through any type of network, including a local area network (LAN) or a wide area network (WAN), or may be connected to an external computer (e.g., through the Internet using an Internet service provider).

[0235] Finally, it should be noted that although the above embodiments have been described in the specification and drawings of this application, this does not limit the scope of patent protection of this application. All technical solutions generated by replacing or modifying equivalent structures or equivalent processes based on the essential concept of this application using the contents recorded in the specification and drawings of this application, as well as directly or indirectly implementing the technical solutions of the above embodiments in other related technical fields, are included in the scope of patent protection of this application.

Claims

1. A battery cluster SOC estimation method, characterized in that: The method comprises: S1. Calibrate the rated capacity of the battery cluster; S2, determining whether the battery cluster is in a static state; if so, executing S3, if not, executing S4; S3, obtaining the average cell voltage and static display SOC of the battery cluster, and searching for a calibration SOC corresponding to the average cell voltage of the battery cluster from a set OCV-SOC data table, and correcting the static display SOC of the battery cluster to the found calibration SOC; S4, determining whether the battery cluster is in a charging state; if so, executing S5, if not, executing S12; S5, when the battery cluster is in a charging state, determining whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in an OCV-SOC data table when the battery cluster is in a static state; if so, executing S6, if not, executing S9; S6, determining whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference=calibrated SOC of the battery cluster-static display SOC of the battery cluster; if yes, executing S7, if no, executing S8; S7. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2); S8. Calculate the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster; S9, determining whether the difference between the real-time SOC of the battery cluster and the static display SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the static display SOC of the battery cluster - the calibrated SOC of the battery cluster; if so, executing S10, if not, executing S11; S10, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5); S11, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster; S12, determining that the battery cluster is in a discharging state, and when the battery cluster is in the discharging state, determining whether the calibrated SOC of the battery cluster is greater than or equal to the static displayed SOC of the battery cluster; the calibrated SOC of the battery cluster is determined by searching in an OCV-SOC data table when the battery cluster is in a static state; if so, executing S13, if not, executing S16; S13, determining whether the difference between the static display SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to the ∆SOC difference; at this time, the ∆SOC difference = the calibrated SOC of the battery cluster - the static display SOC of the battery cluster; if yes, executing S14, if no, executing S15; S14, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5); S15, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + the ampere-hour integrated amount of the battery cluster; S16, determining whether the difference between the static displayed SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to ∆SOC difference*2; at this time, ∆SOC difference=static displayed SOC of the battery cluster-calibrated SOC of the battery cluster; if yes, executing S17, if no, executing S18; S17, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2); S18, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

2. The battery cluster SOC estimation method according to claim 1, characterized in that: The S1 includes: S101, after fully charging the battery cluster, recording the cumulative charging capacity and the cumulative discharging capacity of the battery cluster when charging stops; S102, after the battery cluster is fully discharged within a second set time, recording the cumulative charging capacity of the battery cluster when discharge stops and the cumulative discharging capacity of the battery cluster when discharge stops; S103, calculating the actual capacity of the battery cluster according to the cumulative charging capacity when charging stops, the cumulative discharging capacity when charging stops, the cumulative charging capacity when discharging stops, and the cumulative discharging capacity when discharging stops, and correcting the rated capacity of the battery cluster to the calculated actual capacity, thereby completing the calibration of the rated capacity of the battery cluster.

3. The battery cluster SOC estimation method according to claim 2, characterized in that: The calculation formula for the actual capacity of the battery cluster is: The actual capacity of the battery cluster=(cumulative discharge capacity when discharge stops−cumulative discharge capacity when charge stops)−(cumulative charge capacity when discharge stops−cumulative charge capacity when charge stops).

4. The battery cluster SOC estimation method according to claim 1, characterized in that: Before S3, the method further includes: S2.5 determines whether the static time of the battery cluster is greater than the first set time; if so, execute S3, if not, continue to execute S2.

5.

5. The battery cluster SOC estimation method according to claim 1, characterized in that: The S3 is specifically: The average cell voltage and static display SOC of the battery cluster are obtained, and a calibration SOC corresponding to the average cell voltage of the battery cluster is searched through a binary search from a set OCV-SOC data table, and the static display SOC of the battery cluster is corrected to the searched calibration SOC.

6. The battery cluster SOC estimation method according to claim 1, characterized in that: The calculation formula of the real-time SOC of the battery cluster is: The real-time SOC of the battery cluster=(the remaining capacity of the battery cluster÷the actual capacity of the battery cluster)*100%.

7. The battery cluster SOC estimation method according to claim 1, characterized in that: The method further comprises: S21, during the charging process of the battery cluster, when the real-time SOC of the battery cluster is greater than 75%, obtaining the maximum single cell voltage of the battery cluster and the real-time SOC of the battery cluster; S22, searching a set OCV-SOC data table for a dynamic calibration SOC of the battery cluster corresponding to the maximum cell voltage of the battery cluster; S23, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S24, if not, executing S27; S24, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S25, if not, executing S26; S25, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2); S26, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4); S27, determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S28, if not, executing S211; S28, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S29, if not, executing S210; S29, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5); S210, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25); S211, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

8. The battery cluster SOC estimation method according to claim 1, characterized in that: The method further comprises: S31, during the discharge process of the battery cluster, when the real-time SOC of the battery cluster is less than 25%, obtaining the minimum cell voltage of the battery cluster and the real-time SOC of the battery cluster; S32, searching a set OCV-SOC data table for a dynamic calibration SOC of the battery cluster corresponding to a minimum cell voltage of the battery cluster; S33, determining whether the dynamic calibration SOC of the battery cluster is greater than the real-time SOC of the battery cluster; if so, executing S34, if not, executing S37; S34, determining whether the difference between the dynamic calibration SOC of the battery cluster and the real-time SOC of the battery cluster is less than or equal to 5; if so, executing S35, if not, executing S36; S35, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.5); S36, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 0.25); S37, determining whether the dynamic calibration SOC of the battery cluster is less than the real-time SOC of the battery cluster; if so, executing S38, if not, executing S311; S38, determining whether the difference between the real-time SOC of the battery cluster and the dynamic calibration SOC of the battery cluster is less than or equal to 5; if so, executing S39, if not, executing S310; S39, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 2); S310, calculating the SOC of the battery cluster after calibration according to the following formula: The SOC of the battery cluster after calibration = the remaining capacity of the battery cluster + (the ampere-hour integral of the battery cluster * 4); S311, determining that the dynamic calibration SOC of the battery cluster is equal to the real-time SOC of the battery cluster, and calculating the calibrated SOC of the battery cluster according to the following formula: The SOC of the battery cluster after calibration=the remaining capacity of the battery cluster+the ampere-hour integrated amount of the battery cluster.

9. 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 battery cluster SOC estimation method according to any one of claims 1 to 8 is implemented.

10. A computer-readable storage medium having computer-executable instructions stored thereon, characterized in that: The computer executable instructions are executed by a computer processor to implement the battery cluster SOC estimation method according to any one of claims 1 to 8.

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