Fault processing method, device and equipment
By identifying and replacing the faulty battery cells in the energy storage battery and detecting the status of the new group, the problem that the battery cells in the prior art cannot be fully utilized is solved, improving utilization rate and reducing maintenance costs.
Patent Information
- Application Number
- CN202411639107.0
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-11-15
- Publication Date
- 2025-03-14
AI Technical Summary
The prior art will directly replace the entire energy storage battery after the service life of the energy storage battery expires, resulting in some battery cells being unable to be fully utilized, resulting in waste of resources and high maintenance costs.
By determining the battery parameters of each cell, such as internal resistance, health indicators and voltage outliers, identify the faulty cell and generate a work order for replacement. After the replacement is completed, check whether the status of the new group meets the preset conditions to ensure the normal operation of the battery pack.
Accurate identification and replacement of faulty battery cells is achieved, the utilization rate of battery cells is improved, resource waste is reduced, and maintenance costs of energy storage batteries are reduced.
Smart Images
Figure CN119628139A_ABST
Abstract
Description
Technical Field
[0001] The present application relates to the field of battery technology, and in particular to a fault handling method, device and equipment. Background Art
[0002] The power reserve system is a common safety redundant device in the communication room. At present, most of them use energy storage batteries to realize the power reserve function. Since the service life of energy storage batteries is limited, the entire energy storage battery will be replaced directly after the service life of the energy storage battery expires. However, in fact, some battery cells in the energy storage battery can still maintain good performance. This method of replacing the entire energy storage battery causes some battery cells to not be fully utilized. Summary of the invention
[0003] The present application provides a fault handling method, device and equipment for improving the utilization rate of battery cells.
[0004] In a first aspect, an embodiment of the present application provides a fault handling method, comprising: determining battery parameters of each battery cell in a first battery group, the battery parameters including internal resistance, health index and voltage outlier degree; determining whether a first battery cell in the first battery group has a fault based on preset detection parameters and the battery parameters of each battery cell; if it is determined that the first battery cell has a fault, generating a work order to be processed and sending it to a maintenance system; receiving work order data from the maintenance system, and determining that the first battery cell has been replaced with a second battery cell based on a first battery parameter input by a user, the work order data including the battery parameters of the second battery cell; determining whether the second battery group meets a preset condition, the preset condition being used to indicate that the second battery group is in a normal state, and the second battery group is obtained after replacing the first battery cell in the first battery group.
[0005] In an embodiment of the present application, the internal resistance, health index, voltage outlier and other battery parameters of each battery cell are used to identify whether there is a faulty first battery cell in the first battery pack. When the first battery cell is determined to be faulty, the first battery cell is replaced by interacting with the maintenance system for work order data. When the replacement is completed, whether the second battery pack meets the preset conditions is detected to determine whether the status of the second battery pack is normal. Compared with the method of replacing the entire battery pack in the prior art, the embodiment of the present application can accurately identify and replace the faulty battery cells in the first battery pack, while other battery cells with better performance can continue to be used, thereby improving the utilization rate of the battery cells, reducing resource waste, and reducing the maintenance cost of the energy storage battery.
[0006] In one possible implementation, determining the battery parameters of each battery cell in the first battery group includes: obtaining the voltage value and current value of each battery cell during the charging and discharging process within a preset time period; determining the internal resistance of each battery cell based on the pre-stored initial internal resistance of each battery cell, the voltage value and the current value, combined with a preset least squares method.
[0007] In one possible implementation, determining battery parameters of each battery cell in a first battery group includes: determining an increased capacity of each battery cell after charging of each battery cell is completed, the increased capacity being used to indicate the capacity charged into each battery cell during the charging process; determining a first remaining available power of each battery cell according to a first open circuit voltage of each battery cell after charging is completed; determining a first actual capacity of each battery cell according to the first remaining available power, a second remaining available power and the increased capacity, the second remaining available power being the remaining available power of each battery cell before charging; and determining a health indicator of each battery cell according to the first actual capacity and a pre-stored rated capacity of each battery cell.
[0008] In a possible implementation, the first actual capacity of each battery cell is determined based on the first remaining available power, the second remaining available power and the increased capacity, including: determining the power change value of each battery cell based on the first remaining available power and the second remaining available power; determining the first actual capacity based on a preset filter coefficient, the increased capacity, the power change value and the second actual capacity, the second actual capacity being used to indicate the historical actual capacity of each battery cell.
[0009] In a possible implementation, the detection parameters include a health indicator change boundary value, an internal resistance boundary value and a voltage outlier change value; determining whether a first battery cell in the first battery group has a fault based on preset detection parameters and battery parameters of each battery cell comprises: determining that the first battery cell has a fault when any of the following fault conditions are met based on the detection parameters and battery parameters of each battery cell; wherein the fault conditions include at least: a change value between a health indicator of the first battery cell and a historical health indicator of the first battery cell exceeds a preset health indicator change boundary value; the internal resistance of the first battery cell exceeds the internal resistance boundary value; a change value between a voltage outlier of the first battery cell and an average voltage outlier in the first battery group exceeds the voltage outlier change value.
[0010] In a possible implementation, before determining whether the second battery group meets preset conditions, the method also includes: determining an average available capacity of each battery cell in the second battery group; determining a differential capacity of each battery cell compared to the average available capacity based on the average available capacity and the actual available capacity of each battery cell, the differential capacity being used to indicate the capacity that needs to be replenished or the capacity that needs to be discharged of each battery cell; balancing each battery cell in the second battery group based on the differential capacity of each battery cell until each battery cell meets a balancing condition, and determining that the second battery cell has been balanced with other battery cells in the second battery group, the balancing condition being that the balancing time of each battery cell reaches a preset balancing time or the voltage difference value between the each battery cell is less than a preset threshold.
[0011] In a second aspect, an embodiment of the present application provides a fault handling device, comprising: a determination module, used to determine the battery parameters of each battery cell in a first battery group, the battery parameters including internal resistance, health index and voltage outlier degree; a fault identification module, used to determine whether a first battery cell in the first battery group has a fault based on preset detection parameters and the battery parameters of each battery cell; a transceiver module, used to generate a work order to be processed and send it to a maintenance system if it is determined that the first battery cell has a fault; the transceiver module is also used to receive work order data from the maintenance system; the determination module is also used to determine that the first battery cell has been replaced with a second battery cell based on the first battery parameters input by a user, the work order data including the battery parameters of the second battery cell; a detection module, used to determine whether the second battery group meets a preset condition, the preset condition is used to indicate that the second battery group is in a normal state, and the second battery group is obtained after replacing the first battery cell in the first battery group.
[0012] In a possible implementation, the determination module is specifically used to: obtain the voltage value and current value of each battery cell during the charging and discharging process within a preset time period; determine the internal resistance of each battery cell based on the pre-stored initial internal resistance of each battery cell, the voltage value and the current value, combined with a preset least squares method.
[0013] In a possible implementation, the determination module is specifically used to: determine the increased capacity of each battery cell after charging of each battery cell is completed, and the increased capacity is used to indicate the capacity charged to each battery cell during the charging process; determine the first remaining available power of each battery cell according to the first open circuit voltage of each battery cell after charging is completed; determine the first actual capacity of each battery cell according to the first remaining available power, the second remaining available power and the increased capacity, and the second remaining available power is the remaining available power of each battery cell before charging; determine the health indicator of each battery cell according to the first actual capacity and the pre-stored rated capacity of each battery cell.
[0014] In a possible implementation, the determination module is specifically used to: determine the charge change value of each battery cell based on the first remaining available power and the second remaining available power; determine the first actual capacity based on a preset filter coefficient, the increased capacity, the charge change value and the second actual capacity, and the second actual capacity is used to indicate the historical actual capacity of each battery cell.
[0015] In a possible implementation, the detection parameters include a health indicator change boundary value, an internal resistance boundary value and a voltage outlier change value; the fault identification module is specifically used to: determine, based on the detection parameters and the battery parameters of each battery cell, that the first battery cell has a fault when any of the following fault conditions is met; wherein the fault conditions include at least: a change value between the health indicator of the first battery cell and a historical health indicator of the first battery cell exceeds a preset health indicator change boundary value; the internal resistance of the first battery cell exceeds the internal resistance boundary value; a change value between the voltage outlier of the first battery cell and the average voltage outlier in the first battery group exceeds the voltage outlier change value.
[0016] In a possible implementation, the determination module is further used to determine the average available capacity of each battery cell in the second battery group before determining whether the second battery group meets the preset conditions; determine the differential capacity of each battery cell compared to the average available capacity based on the average available capacity and the actual available capacity of each battery cell, and the differential capacity is used to indicate the capacity that needs to be supplemented or the capacity that needs to be discharged of each battery cell; balance each battery cell in the second battery group based on the differential capacity of each battery cell until each battery cell meets the balancing condition, and determine that the second battery cell and other battery cells in the second battery group have been balanced, and the balancing condition is that the balancing time of each battery cell reaches the preset balancing time or the voltage difference value between the each battery cell is less than a preset threshold.
[0017] In a third aspect, an embodiment of the present application provides a fault handling device, comprising: at least one processor, and a memory communicatively connected to the at least one processor; wherein the memory stores instructions executable by the at least one processor, and the at least one processor implements the method described in the first aspect and any possible implementation manner by executing the instructions stored in the memory.
[0018] In a fourth aspect, an embodiment of the present application provides a computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions. When the computer instructions are executed on a computer, the computer executes the method described in the first aspect and any possible implementation manner.
[0019] In a fifth aspect, an embodiment of the present application provides a computer program product, comprising computer instructions, which, when executed on a computer, enables the method described in the first aspect and any possible implementation method to be implemented.
[0020] The beneficial effects of the second to fifth aspects can be referred to the contents described in the first aspect above, and will not be repeated here. BRIEF DESCRIPTION OF THE DRAWINGS
[0021] Figure 1 A schematic diagram of an application scenario of a fault handling method provided in an embodiment of the present application;
[0022] Figure 2 A schematic diagram of the structure of an energy storage battery provided in an embodiment of the present application;
[0023] Figure 3 A flowchart of a fault handling method provided in an embodiment of the present application;
[0024] Figure 4A schematic flow chart of a method for determining a health indicator of a battery cell provided in an embodiment of the present application;
[0025] Figure 5 A schematic diagram of a flow chart for executing a second battery pack balancing function provided in an embodiment of the present application;
[0026] Figure 6 A schematic diagram of the structure of a fault handling device provided in an embodiment of the present application;
[0027] Figure 7 A schematic diagram of the structure of a fault handling device provided in an embodiment of the present application. DETAILED DESCRIPTION
[0028] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme in the embodiment of the present application will be clearly and completely described below in conjunction with the drawings in the embodiment of the present application. Obviously, the described embodiment is only a part of the embodiment of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by ordinary technicians in the field without making creative work are within the scope of protection of the present application. In the absence of conflict, the embodiments in the present application and the features in the embodiments can be arbitrarily combined with each other. In addition, although the logical order is shown in the flow chart, in some cases, the steps shown or described can be performed in an order different from that here.
[0029] The terms "first" and "second" in the specification and claims of the present application and the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order. In addition, the term "comprising" and any of their variations are intended to cover non-exclusive protection. For example, a process, method, system, product or device comprising a series of steps or units is not limited to the listed steps or units, but optionally also includes steps or units that are not listed, or optionally also includes other steps or units inherent to these processes, methods, products or devices. "Multiple" in the present application can mean at least two, for example, two, three or more, and the embodiments of the present application are not limited.
[0030] The following is a description of exemplary embodiments of the present application in conjunction with the accompanying drawings, including various details of the embodiments of the present application to facilitate understanding, which should be considered as merely exemplary. Therefore, those of ordinary skill in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope of the present application. Similarly, for the sake of clarity and conciseness, the description of well-known functions and structures is omitted in the following description. It should be noted that in the embodiments of the present application, certain software, components, models and other existing solutions in the industry may be mentioned, which should be considered as exemplary, and their purpose is only to illustrate the feasibility of the implementation of the technical solution of the present application, but it does not mean that the applicant has or will necessarily use the solution.
[0031] To facilitate understanding, the terms involved in the embodiments of the present application are explained below.
[0032] 1. State of health (SOH), which indicates the health status of the battery.
[0033] 2. The remaining available power (state of charge, SOC) refers to the available state of the remaining charge in the battery, that is, the remaining available power of the battery, usually in the form of a percentage, or it can also be called the remaining battery power percentage.
[0034] 3. Actual capacity: refers to the amount of electricity that a battery can provide under a certain discharge condition (a certain depth, a certain current density and a termination voltage). In layman's terms, the actual capacity is the capacity of a fully charged battery. The actual capacity of a new battery is usually slightly higher than the rated capacity. As the number of times the battery is charged and discharged increases, the battery will gradually wear out, or be affected by the external environment (such as low temperature), resulting in a decrease in the actual capacity.
[0035] 4. Voltage outliers: refers to the situation where the voltage value deviates significantly from the expected or normal range. In the power system, voltage is one of the important parameters, which maintains the stability and quality of power supply. Under normal circumstances, the voltage will fluctuate within a certain range, but if the voltage suddenly rises or falls sharply and exceeds a certain range, this voltage value can be called an outlier.
[0036] 5. Battery Management System (BMS): also known as battery steward, is a system used to manage batteries. Its main function is to monitor the status of energy storage batteries, such as battery voltage, current, temperature and other parameters.
[0037] 6. Least Squares Method: Also known as the least square method, it is a mathematical optimization technique that finds the best function match for the data by minimizing the sum of squares of errors.
[0038] Please refer to Figure 1 , is a schematic diagram of an application scenario of a fault handling method provided in an embodiment of the present application. Figure 1 As shown, the schematic diagram includes an energy storage battery 110, a battery management system 120, a fault handling device 130 and a maintenance system 140. The fault handling device 130 can perform wired or wireless communication with the battery management system 120 and the maintenance system 140 respectively.
[0039] The energy storage battery 110 is composed of a plurality of battery cells, which can be regarded as a battery pack for storing electric energy. Figure 2 , which is a schematic structural diagram of an energy storage battery 110 provided in an embodiment of the present application. Figure 2 The energy storage battery 110 includes battery cell 1, battery cell 2, ..., battery cell n-1, battery cell n, where n is a positive integer. It should be noted that, Figure 2 It is only an example of the energy storage battery 110, and does not limit the specific structure of the energy storage battery and the number of battery cells included in the energy storage battery. The battery management system 120 is used to monitor the status of the energy storage battery 110. The fault handling device 130 refers to a device or equipment with data processing capability and data transceiving capability, such as a terminal device or a server, etc. The terminal device includes but is not limited to: a personal computer (PC), a tablet computer, a laptop computer, a PDA, a mobile Internet device (MID), a wireless terminal device in industrial control, a wireless terminal device in a smart grid, etc. The maintenance system 140 refers to a device or equipment with data processing capability and data transceiving capability, such as a terminal device or a server, wherein the content of the terminal device can correspond to the content described above. The maintenance system 140 refers to the data processing system on the supplier side corresponding to the energy storage battery 110, that is, the maintenance system 140 is used to provide battery maintenance services for the energy storage battery 110.
[0040] In a possible implementation, the fault handling device 130 and the battery management system 120 are integrated into one device, or are implemented in two devices respectively, which is not limited in the embodiment of the present application.
[0041] Exemplarily, the fault handling device 130 can determine whether a first battery cell in the energy storage battery 110 is faulty based on the battery parameters of each battery cell in the energy storage battery 110 collected by the battery management system 120, based on the pre-stored detection parameters and the battery parameters of each battery cell. And in the case of determining that the first battery cell is faulty, a maintenance work order is sent to the maintenance system 140 so that the maintenance system 140 provides corresponding battery maintenance services based on the maintenance work order. When the fault handling device 130 receives the work order data from the maintenance system 140 and obtains the first battery parameter of the second battery cell input by the user, it is determined that the first battery cell has been replaced with the second battery cell. Further, the fault handling device 130 determines whether the state of the second battery pack after replacing the first battery cell is normal. Among them, the specific manner in which the fault handling device 130 determines the battery parameters of each battery cell, determines whether the first battery cell is faulty, and determines whether the second battery pack can operate normally will be described in detail below.
[0042] Please refer to Figure 3 , is a flowchart of a fault handling method provided in an embodiment of the present application. The following is a flowchart of a fault handling method performed by a fault handling device. Figure 3 The steps shown are explained. Figure 3 The fault handling device involved is, for example, Figure 1 The fault handling device shown, Figure 3 The maintenance systems involved are, for example, Figure 1 Repair system shown.
[0043] S301, determining battery parameters of each battery cell in a first battery group, where the battery parameters include internal resistance, health index, and voltage outlier.
[0044] The specific methods for the fault handling device to determine the internal resistance, health index and voltage outlier of each battery cell are described below.
[0045] 1. The fault handling device determines the internal resistance of each battery cell.
[0046] The fault handling device can obtain the voltage and current values of each battery cell during the charge and discharge process within a preset time period, and determine the internal resistance of each battery cell based on the pre-stored initial internal resistance, voltage and current values of each battery cell in combination with a preset least squares method.
[0047] Specifically, the fault handling device iterates and converges the initial internal resistance based on the collected voltage and current values of each charge and discharge until the calculated internal resistance meets the preset difference. The internal resistance at this time is the internal resistance of each battery cell.
[0048] Exemplarily, the fault handling device can determine the relationship between the terminal voltage, current, and ohmic internal resistance of each battery cell according to the equivalent circuit model of the battery. For example, for a simple ohmic model, it can be shown as the following formula 1:
[0049] U=I×R0+UOCV Formula 2
[0050] Among them, U is the terminal voltage of each battery cell, I is the current, R0 is the ohmic internal resistance, and UOCV is the open circuit voltage of each battery cell.
[0051] The goal of the least squares method is to find a set of parameters (ohmic internal resistance in the embodiment of the present application) so that the sum of squares of the errors between the model prediction value and the actual measurement value is minimized, which can be specifically shown in the following formula 1:
[0052] ∑(Ui-Ii×R0-UOCVi)2→min Formula 1
[0053] Wherein, Ui, Ii and UOCVi are respectively the voltage, current and open circuit voltage of the ith measurement point. In the embodiment of the present application, the current and voltage data within one minute are usually collected.
[0054] By taking the derivative of the above error sum of squares function and setting it equal to 0, we can get an estimate of R0. After getting the estimate of R0, we can use other methods (such as experimental measurement, model verification, etc.) to verify its accuracy. If the estimated value is significantly different from the true value, we may need to recheck the data, model, or solution process.
[0055] 2. The fault handling device determines the health indicators of each battery cell.
[0056] Combine the following Figure 4 The flowchart of a method for determining a health indicator of a battery cell is shown to explain the specific manner in which the fault handling device determines the health indicator of a battery cell.
[0057] S401, determining whether a battery cell meets a first measurement condition.
[0058] Among them, the first measurement condition refers to whether the battery cell has entered the valley power replenishment stage and the battery cell has been stationary for a preset time. Among them, the valley power replenishment stage refers to the stage of charging the battery during the low valley power period. Since the battery cell will be in an unstable state for a period of time after charging and discharging, it is necessary to let the battery stand for a period of time before determining the health indicators of the battery cell. If the battery cell is not stationary for the preset time, the state of the battery cell is unstable, and the health indicators determined are also inaccurate. Therefore, in this case, the measurement of this health indicator is abandoned. Among them, the preset time length can be set according to actual needs, for example, 30 minutes, and the embodiment of the present application is not limited to this.
[0059] It should be understood that each battery cell in the first battery group is discharged externally or charged internally as a whole, and therefore, each battery cell in the first battery group should satisfy or not satisfy the first measurement condition at the same time.
[0060] If it is determined that the battery cell meets the first measurement condition, S402 is executed, that is, the second remaining available power of the battery cell is determined according to the second open circuit voltage of the battery cell. If it is determined that the battery cell does not meet the first measurement condition, the current health indicator determination process is terminated.
[0061] S402 , determining a second remaining available power of the battery cell according to a second open circuit voltage of the battery cell.
[0062] The second remaining available power refers to the remaining available power of the battery cell before charging, or is called the initial SOC value of the battery cell. The second open circuit voltage refers to the terminal voltage of the battery cell in an open circuit state before charging. The second open circuit voltage can be measured by the BMS.
[0063] Specifically, the fault handling device may determine the second remaining available power of the battery cell according to the pre-stored correspondence between the open circuit voltage and the remaining available power, and the second open circuit voltage.
[0064] S403, charging the first battery pack according to a preset charging rate until the charging cut-off voltage is reached, and determining the increased capacity of the battery cell.
[0065] The preset charging rate refers to the current value required when the battery is charged to its rated capacity in a specified time. In layman's terms, charging the first battery pack according to the preset charging rate can be understood as charging the battery cells with a constant current until the cut-off charging voltage is reached, and the cut-off charging voltage is used to indicate that the battery cells are full or charging is finished. The increased capacity refers to the capacity charged into the battery cells during the charging process.
[0066] Specifically, the fault handling device may determine the increased capacity according to the preset charging rate and the charging time. Exemplarily, the fault handling device determines the product of the preset charging rate and the charging time as the increased capacity, or ampere-hour Ah capacity.
[0067] S404, determining whether the battery cell meets a second measurement condition.
[0068] The second measurement condition includes that the battery cell has no discharge demand and the charge and discharge current of the battery cell is less than a preset value.
[0069] The battery cell has no discharge demand, which means that the fault handling device has not received a power supply request from other devices. If the battery cell charge and discharge current is less than a preset value, it means that the battery cell has finished charging, wherein the preset value can be set according to actual needs, and the embodiment of the present application does not limit this.
[0070] If the fault handling device determines that the battery cell meets the second measurement condition, it executes S405, that is, determines whether the battery cell meets the third measurement condition. If the battery cell does not meet the second measurement condition, the current health indicator determination process ends.
[0071] S405 , determining whether the battery cell meets a third measurement condition.
[0072] The third measurement condition indicates that the battery cell has been at rest for a preset time. The battery cell has been at rest for a preset time may refer to the above-mentioned content, which will not be repeated here.
[0073] If the fault handling device determines that the battery cell meets the third measurement condition, it executes S406, that is, determines the first remaining available power of the battery cell according to the first open circuit voltage of the battery cell. If the battery cell does not meet the third measurement condition, it repeats S404 until it is determined that the battery cell meets the third measurement condition.
[0074] S406 , determining a first remaining available power of the battery cell according to a first open circuit voltage of the battery cell after charging is completed.
[0075] The first open circuit voltage is measured by the BMS when the fault handling device determines that the battery cell has met the third measurement condition. The method for determining the first remaining available power by the fault handling device can correspond to the method for determining the second remaining available power by the fault handling device described above, which will not be repeated here.
[0076] S407 , determining a first actual capacity of the battery cell according to the first remaining available power, the second remaining available power, and the increased capacity.
[0077] Specifically, the fault handling device can determine the power change value of the battery cell according to the first remaining available power and the second remaining available power, and determine the calculation result between the power change value and the increased capacity as the first actual capacity of the battery cell. Exemplarily, a calculation method for determining the first actual capacity is as follows:
[0078] Q1=Q charge / (SOC end -SOC int )
[0079] Among them, Q1 represents the first actual capacity, Q charge Indicates increased capacity, SOC endIndicates the first remaining available power, SOC int Indicates the remaining available power.
[0080] In a possible implementation, in order to improve the accuracy of determining the first actual capacity, the first actual capacity may also be determined in combination with a preset filter coefficient and a second actual capacity. The second actual capacity is used to indicate the historical actual capacity of the battery cell, and the historical actual capacity may refer to the first actual capacity determined in the last health indicator measurement of the battery cell, or when the health indicator of the battery cell is determined for the first time, the second actual capacity may refer to the initial actual capacity of the battery cell. Specifically, the charge change value of the battery cell is determined based on the first remaining available power and the second remaining available power; and the result of the operation between the preset filter coefficient, the increased capacity, the charge change value and the second actual capacity is determined as the first actual capacity. Exemplarily, a calculation method for determining the first actual capacity is as follows:
[0081] Q1=Q2*a+b*[Q charge / (SOC end -SOC int )]
[0082] Wherein, Q2 represents the second actual capacity, a and b are preset filter coefficients, for example, a=0.05, b=0.95.
[0083] S408: Determine a health indicator of the battery cell according to the first actual capacity and the pre-stored rated capacity.
[0084] Specifically, the fault handling device may determine the calculation result between the first actual capacity and the rated capacity as the health index of the battery cell. Exemplarily, a calculation formula for determining the health index of the battery cell is as follows:
[0085] SOH=Q1 / Q0
[0086] Among them, SOH represents the health index of the battery cell, and Q0 represents the rated capacity of the battery cell.
[0087] In a possible implementation, in order to improve the accuracy of determining the health index of the battery cell, the fault processing unit may calculate the current health index of the battery cell by combining the historical health index of the battery cell and a preset filter coefficient, wherein the historical health index is calculated in the last health index measurement of the battery cell.
[0088] Exemplarily, a calculation formula for determining the health index of a battery cell is as follows:
[0089] SOH=a*SOH(t)+b*SOH(t-1)
[0090] Wherein, SOH represents the calibrated health index. SOH(t) represents the calculated value based on the aforementioned first actual capacity and rated capacity. SOH(t-1) represents the historical health index. a and b are preset filter coefficients.
[0091] It should be noted that, in actual application, it is sufficient to choose to perform calibration once in the first actual capacity calculation stage or in the health indicator calculation stage.
[0092] Figure 4 The process shown is a process for calculating the health index of a battery cell. The health index of each battery cell in the first battery pack can be referred to accordingly. Figure 4 The process shown is confirmed, and the embodiments of the present application will not be repeated here.
[0093] 3. The fault handling device determines the voltage outlier degree of each battery cell.
[0094] The fault handling device can collect the voltage outlier of each battery cell through the BMS.
[0095] S302 , determining whether a first battery cell in a first battery group fails according to preset detection parameters and battery parameters of each battery cell.
[0096] The detection parameters include a health index change boundary value, an internal resistance boundary value, and a voltage outlier change value. The internal resistance boundary value includes an internal resistance upper boundary value and an internal resistance lower boundary value. The voltage outlier change value is an absolute value. The first battery cell may be any battery cell in the first battery pack.
[0097] Specifically, the fault processing device can determine that the first battery cell has a fault when the first battery cell meets any of the following fault conditions based on the detection parameters and the battery parameters of each battery cell. The fault conditions include at least:
[0098] (1) The change between the health indicator of the first battery cell and the historical health indicator of the first battery cell exceeds a preset health indicator change boundary value. The historical health indicator may refer to the health indicator measured last time, or the health indicator before a preset time interval, for example, one week ago, half a month ago, etc., which is not limited in the present embodiment.
[0099] (2) The internal resistance of the first battery cell exceeds the internal resistance boundary value.
[0100] Since the internal resistance of the first battery cell may increase or decrease, when the internal resistance of the first battery cell is less than the internal resistance lower limit boundary value or greater than the internal resistance upper limit boundary value, it is determined that the first battery cell is abnormal.
[0101] (3) A change value between the voltage outlier degree of the first battery cell and the average voltage outlier degree in the first battery group exceeds the voltage outlier degree change value.
[0102] If it is determined that the first battery cell meets any of the above fault conditions, it is determined that the first battery cell has failed, and S303 is executed, that is, a work order to be processed is generated and sent to the maintenance system. If it is determined that the first battery cell does not meet all of the above fault conditions, it is determined that the first battery cell has not failed, and the fault handling process for the first battery cell is terminated.
[0103] S303: Generate a work order to be processed and send it to the maintenance system.
[0104] The work order to be processed includes battery parameters of the first battery cell.
[0105] The fault handling device generates a work order to be processed based on the battery parameters of the first battery cell, and sends the work order to be processed to the maintenance system. Correspondingly, the maintenance system receives the work order to be processed from the fault handling device.
[0106] After the maintenance system receives the work order to be processed, the corresponding maintenance personnel will determine the second battery cell that matches the first battery cell in the work order to be processed based on the battery parameters of the first battery cell, write the battery parameters of the second battery cell into the work order to be processed, generate the work order data and send it to the fault handling device. The battery parameters of the second battery cell include the initial actual capacity, rated capacity, initial internal resistance, etc. of the second battery cell.
[0107] In a possible implementation, before sending a pending work order to a maintenance system, after the fault handling device determines that the first battery cell has failed, an early warning may be triggered to prompt a worker to inspect the first battery cell to further determine whether the first battery cell has a fault.
[0108] S304, receiving work order data from a maintenance system, and determining that the first battery cell has been replaced with a second battery cell according to the first battery parameter input by the user, wherein the work order data includes the battery parameter of the second battery cell.
[0109] When the user replaces the first battery cell with the second battery cell offline, the user needs to input the first battery parameter of the replaced second battery cell. When the fault handling device obtains the first battery parameter, it determines that the first battery cell has been replaced with the second battery cell.
[0110] In a possible implementation, after the fault handling device obtains the first battery parameters, it can also compare the first battery parameters with the battery parameters of the second battery cell in the work order data to ensure that the replaced second battery cell is the correct second battery cell.
[0111] S305, determining whether the second battery pack meets a preset condition, where the preset condition is used to indicate that the second battery pack is in a normal state, and the second battery pack is obtained by replacing the first battery cell in the first battery pack.
[0112] Among them, the preset conditions are, for example, that the charge and discharge power of the second battery pack exceeds 80% of the preset power of the system, and the capacity of the second battery pack exceeds 80% of the preset capacity of the system. The specific values can be set according to actual needs, and the embodiments of the present application are not limited to this. The normal state of the second battery pack can mean that the battery state of the second battery pack is normal and meets the use requirements of the energy storage battery.
[0113] Specifically, after the second battery pack performs the charge and discharge operation, the charge and discharge power and capacity of the second battery pack can be determined. If the charge and discharge power of the second battery pack exceeds 80% of the system preset power and the capacity of the second battery pack exceeds 80% of the system preset capacity, it is determined that the second battery pack meets the preset conditions. If the charge and discharge power of the second battery pack does not exceed 80% of the system preset power or the capacity of the second battery pack does not exceed 80% of the system preset capacity, it is determined that the second battery pack does not meet the preset conditions, and an early warning prompt information can be generated to prompt the staff to perform further processing on the second battery pack.
[0114] In a possible implementation, before determining whether the second battery pack meets the preset condition, a balancing operation is performed on the second battery pack to balance the second battery cell with other battery cells in the second battery pack. Figure 5 A flow chart of a method for performing a balancing operation on a second battery pack is shown in detail.
[0115] S501, determining an average available capacity of each battery cell in a second battery group.
[0116] Specifically, the fault handling device can determine the actual available capacity of each battery cell in the second battery pack according to the third remaining available capacity and the first actual capacity of each battery cell in the second battery pack. It should be understood that the first actual capacity here refers to the current actual capacity of each battery cell in the second battery pack. In particular, the second battery cell is a newly replaced battery cell, and therefore, the first actual capacity of the second battery cell is the initial actual capacity in the work order data. The method for determining the third remaining available capacity can correspond to the method for determining the second remaining available capacity in the previous text, which will not be repeated here.
[0117] Exemplarily, a calculation formula for determining the actual available capacity of each battery cell is as follows:
[0118] Q3=Q1*SOC
[0119] Wherein, Q3 represents the actual available capacity of each battery cell, Q1 represents the first actual capacity of each battery cell, and SOC represents the current third remaining available capacity.
[0120] The fault processing device can determine the average available capacity of each battery cell in the second battery group based on the actual available capacity of each battery cell in the second battery group.
[0121] S502 , determining a difference capacity of each battery cell compared to the average available capacity according to the average available capacity and the actual available capacity of each battery cell.
[0122] The differential capacity is used to indicate the capacity of each battery cell that needs to be supplemented or discharged;
[0123] The fault processing unit can determine the difference between the average available capacity and the actual available capacity of each battery cell compared to the average available capacity. Specifically, the fault processing unit uses the actual available capacity of each battery cell minus the average available capacity. If it is a positive value, it means that the battery cell needs to replenish discharge capacity, and if it is a negative value, it means that the battery cell needs to replenish capacity.
[0124] For example, if the average available capacity is 80 Ah, and the actual available capacity of the second battery cell is 95 Ah, the second battery cell needs to be replenished with 15 Ah of capacity, and +15 Ah represents the difference in capacity between the second battery cell and the average available capacity.
[0125] S503, balancing the battery cells in the second battery group according to the different capacities of the battery cells, until the battery cells meet the balancing condition, and determining that the second battery cell is balanced with other battery cells in the second battery group.
[0126] The balancing condition is that the balancing time of each battery cell reaches a preset balancing time or the voltage difference between each battery cell is less than a preset threshold.
[0127] The fault handling device can control the differential capacity of each battery cell in the second battery pack to complement or discharge each other through the BMS according to the differential capacity of each battery cell, that is, balance each battery cell in the second battery pack. When it is detected that the balancing time of each battery cell in the second battery pack reaches the preset balancing time or the voltage difference value between each battery cell is less than the preset threshold, it is determined that each battery cell in the second battery pack has met the balancing condition. Among them, the preset balancing time can be calculated based on the differential capacity and charging rate of each battery cell, which will not be described in detail here. The voltage difference value between each battery cell can specifically refer to the voltage difference value between the battery cell with the highest voltage and the battery cell with the lowest voltage in the second battery pack.
[0128] Based on the above-mentioned balancing operation, the charge states of the battery cells in the second battery pack can be kept relatively consistent, so as to extend the battery life and improve the charging efficiency and safety.
[0129] Based on the same inventive concept, an embodiment of the present application provides a fault handling device, which is used to implement any of the above fault handling methods, for example, Figure 3 The fault handling method shown, and the device can also realize the functions of the fault handling device mentioned above.
[0130] Please refer to Figure 6 , is a schematic diagram of the structure of a fault handling device provided in an embodiment of the present application. Figure 6 As shown, the fault processing device 600 may include a determination module 601 , a fault identification module 602 , a transceiver module 603 and a detection module 604 .
[0131] Exemplarily, the determination module 601 is used to determine the battery parameters of each battery cell in the first battery group, and the battery parameters include internal resistance, health index and voltage outlier degree; the fault identification module 602 is used to determine whether the first battery cell in the first battery group has a fault based on preset detection parameters and the battery parameters of each battery cell; the transceiver module 603 is used to generate a work order to be processed and send it to the maintenance system if it is determined that the first battery cell has a fault; the transceiver module 603 is also used to receive work order data from the maintenance system; the determination module 601 is also used to determine that the first battery cell has been replaced with a second battery cell based on the first battery parameters input by the user, and the work order data includes the battery parameters of the second battery cell; the detection module 604 is used to determine whether the second battery group meets the preset conditions, and the preset conditions are used to indicate that the second battery group is in a normal state, and the second battery group is obtained after replacing the first battery cell in the first battery group.
[0132] In a possible implementation, the determination module 601 is specifically used to: obtain the voltage value and current value of each battery cell during the charging and discharging process within a preset time period; determine the internal resistance of each battery cell based on the pre-stored initial internal resistance, voltage value and current value of each battery cell, combined with a preset least squares method.
[0133] In a possible implementation, the determination module 601 is specifically used to: determine the increased capacity of each battery cell after charging of each battery cell is completed, the increased capacity is used to indicate the capacity charged into each battery cell during the charging process; determine the first remaining available power of each battery cell according to the first open circuit voltage of each battery cell after charging is completed; determine the first actual capacity of each battery cell according to the first remaining available power, the second remaining available power and the increased capacity, the second remaining available power being the remaining available power of each battery cell before charging; determine the health indicator of each battery cell according to the first actual capacity and the pre-stored rated capacity of each battery cell.
[0134] In a possible implementation, the determination module 601 is specifically used to: determine the charge change value of each battery cell based on the first remaining available power and the second remaining available power; determine the first actual capacity based on a preset filter coefficient, increased capacity, charge change value and the second actual capacity, and the second actual capacity is used to indicate the historical actual capacity of each battery cell.
[0135] In one possible implementation, the detection parameters include a health indicator change boundary value, an internal resistance boundary value, and a voltage outlier change value; the fault identification module 602 is specifically used to: determine, based on the detection parameters and the battery parameters of each battery cell, that a first battery cell has failed when any of the following fault conditions is met; wherein the fault conditions include at least: a change value between a health indicator of the first battery cell and a historical health indicator of the first battery cell exceeds a preset health indicator change boundary value; the internal resistance of the first battery cell exceeds the internal resistance boundary value; a change value between the voltage outlier of the first battery cell and the average voltage outlier in the first battery group exceeds the voltage outlier change value.
[0136] In a possible implementation, the determination module 601 is further used to determine the average available capacity of each battery cell in the second battery group before determining whether the second battery group meets the preset conditions; determine the differential capacity of each battery cell compared to the average available capacity based on the average available capacity and the actual available capacity of each battery cell, and the differential capacity is used to indicate the capacity that needs to be supplemented or the capacity that needs to be discharged for each battery cell; balance each battery cell in the second battery group based on the differential capacity of each battery cell until each battery cell meets the balancing condition, and determine that the second battery cell and other battery cells in the second battery group have been balanced, and the balancing condition is that the balancing time of each battery cell reaches the preset balancing time or the voltage difference value between each battery cell is less than a preset threshold.
[0137] Based on the same inventive concept, an embodiment of the present application provides a fault handling device, which is used to implement any of the above fault handling methods, for example, Figure 3The fault handling method shown, and the device can also realize the function of the fault handling device mentioned above.
[0138] Please refer to Figure 7 , is a schematic diagram of the structure of a fault handling device provided in an embodiment of the present application. Figure 7 As shown, the fault handling device 700 includes at least one processor 701 and a memory 702 communicatively connected to the at least one processor 701 .
[0139] The processor 701 may be a general-purpose processor or a dedicated processor. The processor 701 may include, for example, a baseband processor or a central processing unit. The baseband processor may be used to process communication protocols and communication data. The central processing unit may be used to control the fault handling device 700, execute software programs and / or process data. Different processors may be independent devices or may be arranged in one or more processing circuits, for example, integrated in one or more dedicated integrated circuits.
[0140] In one embodiment, the memory 702 stores instructions that can be executed by at least one processor 701. The at least one processor 701 implements the functions of the fault handling device described above by executing the instructions stored in the memory 702. Accordingly, the steps performed by the fault handling device described above can also be implemented.
[0141] In this embodiment, the fault handling device 700 can also implement the functions of the aforementioned fault handling device 600, and at least one processor 701 in the fault handling device 700 can also implement the functions of the aforementioned determination module 601, fault identification module 602, transceiver module 603 and detection module 604.
[0142] Based on the same inventive concept, an embodiment of the present application provides a computer-readable storage medium, which stores computer instructions. When the computer instructions are executed on a computer, the computer executes any of the fault handling methods described above, for example, Figure 3 The troubleshooting method shown.
[0143] Based on the same inventive concept, an embodiment of the present application provides a computer program product, which includes computer instructions. When the computer program product is executed on a computer, any of the above-mentioned fault handling methods is performed, for example, Figure 3 The fault handling method shown is implemented.
[0144] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment, or an embodiment in combination with software and hardware. Moreover, the present application may adopt the form of a computer program product implemented in one or more computer-usable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) that include computer-usable program code.
[0145] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the processes in the flowchart and / or block diagram. Figure 1 A process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.
[0146] These computer program instructions may also be stored in a computer-readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer-readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 A process or multiple processes and / or boxes Figure 1 A function specified in one or more boxes.
[0147] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operating steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing instructions for implementing the process. Figure 1 A process or multiple processes and / or boxes Figure 1 The steps for the functions specified in one or more boxes.
[0148] Obviously, those skilled in the art can make various changes and modifications to the present application without departing from the spirit and scope of the present application. Thus, if these modifications and variations of the present application fall within the scope of the claims of the present application and their equivalents, the present application is also intended to include these modifications and variations.
Claims
1. A fault handling method, characterized in that: include: Determining battery parameters of each battery cell in the first battery group, wherein the battery parameters include internal resistance, health index, and voltage outlier; Determining whether a first battery cell in the first battery pack fails according to preset detection parameters and battery parameters of each battery cell; If it is determined that the first battery cell fails, a work order to be processed is generated and sent to a maintenance system; receiving work order data from the maintenance system, and determining that the first battery cell has been replaced with a second battery cell according to a first battery parameter input by a user, wherein the work order data includes the battery parameter of the second battery cell; It is determined whether a second battery pack meets a preset condition, wherein the preset condition is used to indicate that the second battery pack is in a normal state, and the second battery pack is obtained after the first battery cell in the first battery pack is replaced.
2. The method according to claim 1, characterized in that Determining a battery parameter of each battery cell in the first battery group includes: Obtaining the voltage value and current value of each battery cell during the charging and discharging process within a preset time period; The internal resistance of each battery cell is determined according to the pre-stored initial internal resistance of each battery cell, the voltage value and the current value in combination with a preset least square method.
3. The method according to claim 1, characterized in that Determining a battery parameter of each battery cell in the first battery group includes: After each battery cell is charged, determining the increased capacity of each battery cell, wherein the increased capacity is used to indicate the capacity of each battery cell charged during the charging process; Determining a first remaining available power of each battery cell according to a first open circuit voltage of each battery cell after charging is completed; Determining a first actual capacity of each battery cell according to the first remaining available power, the second remaining available power, and the increased capacity, wherein the second remaining available power is the remaining available power of each battery cell before charging; A health indicator of each battery cell is determined according to the first actual capacity and the pre-stored rated capacity of each battery cell.
4. The method according to claim 3, characterized in that Determining a first actual capacity of each battery cell according to the first remaining available power, the second remaining available power, and the increased capacity includes: Determining a power change value of each battery cell according to the first remaining available power and the second remaining available power; The first actual capacity is determined according to a preset filter coefficient, the increased capacity, the power change value and the second actual capacity, and the second actual capacity is used to indicate the historical actual capacity of each battery cell.
5. The method according to any one of claims 1 to 4, characterized in that: The detection parameters include health index change boundary value, internal resistance boundary value and voltage outlier change value; Determining whether a first battery cell in the first battery group fails according to preset detection parameters and battery parameters of each battery cell includes: According to the detection parameters and the battery parameters of each battery cell, it is determined that the first battery cell fails when any of the following fault conditions is met; wherein the fault conditions at least include: A change value between the health indicator of the first battery cell and the historical health indicator of the first battery cell exceeds a preset health indicator change boundary value; The internal resistance of the first battery cell exceeds the internal resistance boundary value; A change value between the voltage outlier degree of the first battery cell and an average voltage outlier degree in the first battery group exceeds the voltage outlier degree change value.
6. The method according to any one of claims 1 to 4, characterized in that: Before determining whether the second battery pack meets the preset condition, the method further includes: Determining an average available capacity of each battery cell in the second battery group; Determine, according to the average available capacity and the actual available capacity of each battery cell, a difference capacity of each battery cell compared with the average available capacity, wherein the difference capacity is used to indicate the capacity of each battery cell that needs to be supplemented or the capacity that needs to be discharged; According to the different capacities of the battery cells, the battery cells in the second battery pack are balanced until the battery cells meet the balancing condition, and it is determined that the second battery cell and other battery cells in the second battery pack are balanced, and the balancing condition is that the balancing time of the battery cells reaches the preset balancing time or the voltage difference value between the battery cells is less than a preset threshold.
7. A fault handling device, characterized in that: include: A determination module, configured to determine battery parameters of each battery cell in the first battery group, wherein the battery parameters include internal resistance, health index, and voltage outlier; a fault identification module, configured to determine whether a first battery cell in the first battery pack fails according to preset detection parameters and battery parameters of each battery cell; A transceiver module, configured to generate a work order to be processed and send it to a maintenance system if it is determined that the first battery cell has failed; The transceiver module is also used to receive work order data from the maintenance system; The determination module is further used to determine, based on the first battery parameter input by the user, that the first battery cell has been replaced with a second battery cell, and the work order data includes the battery parameter of the second battery cell; The detection module is used to determine whether the second battery pack meets a preset condition, wherein the preset condition is used to indicate that the second battery pack is in a normal state, and the second battery pack is obtained after replacing the first battery cell in the first battery pack.
8. A fault handling device, characterized in that: include: at least one processor, and a memory communicatively coupled to the at least one processor; The memory stores instructions that can be executed by the at least one processor, and the at least one processor implements the method according to any one of claims 1 to 6 by executing the instructions stored in the memory.
9. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores computer instructions, and when the computer instructions are executed on a computer, the computer is caused to execute the method according to any one of claims 1 to 6.
10. A computer program product, characterized in that The method comprises computer instructions, which, when executed on a computer, enable the method according to any one of claims 1 to 6 to be implemented.