Energy storage system model construction method, device and fault simulation method

Abstract

The present application relates to a model construction method, device and fault simulation method for an energy storage system. An equivalent circuit model of a single cell is constructed based on the operating experimental data of the single cell, a heat generation model and a heat dissipation model of the energy storage system are obtained, and an energy storage system model is constructed based on the heat generation model, the heat dissipation model, the equivalent circuit model and the preset assembly circuit. Because the model construction method of the energy storage system in the present application not only constructs the structural model of the energy storage system based on the equivalent circuit model of the single cell, but also takes into account the heat generation model and the heat dissipation model of the energy storage system, it can accurately simulate the energy storage system, predict and analyze the heat dissipation effect before physical testing, reduce the number and cost of experiments, and improve the safety of fault experiments.

Description

Technical Field

[0001] The present application relates to the technical field of model construction of energy storage systems, and in particular to a model construction method, device and fault simulation method for energy storage systems. Background Art

[0002] Due to the limited availability and pollution of non-renewable energy, clean energy has begun to be widely developed and utilized. However, its instability and intermittent nature make it difficult to integrate effectively into the power grid. Energy storage systems have emerged as a crucial component in absorbing this power. As a steady-state balanced system, energy storage provides a buffer between various power demands, acting as a "reservoir" to smooth power fluctuations, shift peaks and fill valleys, and improve power quality. However, the complex structure of energy storage systems makes extensive testing to predict failure risks prohibitive and costly. Summary of the Invention

[0003] Based on this, it is necessary to provide a model construction method, device and fault simulation method for an energy storage system that can construct a model of the energy storage system to reduce the cost of predicting energy storage system faults in order to address the above technical problems.

[0004] In a first aspect, the present application provides a method for constructing an energy storage system model, wherein the energy storage system includes a plurality of connected single cells; the method includes:

[0005] Constructing an equivalent circuit model of the single cell according to the operating experimental data of the single cell;

[0006] Obtaining a heat generation model and a heat dissipation model of the energy storage system;

[0007] The energy storage system model is constructed based on the heat generation model, the heat dissipation model, the equivalent circuit model and the preset assembly circuit.

[0008] In one embodiment, obtaining the heat dissipation model of the energy storage system includes:

[0009] Obtaining a heat transfer model between the battery cells in the single battery and the external environment;

[0010] Obtaining a heat conduction model between the cells in the single battery;

[0011] Obtaining a heat exchange model between the battery cells in the single battery and the water cooling plate;

[0012] The heat dissipation model is acquired based on the heat transfer model, the heat conduction model, and the heat exchange model.

[0013] In one embodiment, obtaining a heat generation model of the energy storage system includes:

[0014] Obtaining the heating power of each cell in the single battery;

[0015] The heat generation model is constructed based on the heat generation power and the positional relationship between the single cells.

[0016] In one embodiment, the operating experimental data includes state of charge-open circuit voltage curves under different temperature conditions and open circuit voltage-time curves at each state of charge point; constructing an equivalent circuit model of a single single cell based on the operating experimental data of the single cell includes:

[0017] Establishing an equivalent circuit of the single battery, wherein the equivalent circuit has a plurality of circuit parameters to be identified;

[0018] Acquire an experimental data set of the single battery, the experimental data set comprising the state of charge-open circuit voltage curve under different temperature conditions and the open circuit voltage-time curve at each state of charge point;

[0019] The circuit parameters are obtained according to the experimental data set to generate the equivalent circuit model.

[0020] In one embodiment, obtaining each of the circuit parameters according to the experimental data set includes:

[0021] Obtaining a voltage rebound characteristic curve of the single battery based on the state of charge-open circuit voltage curve under the different temperature conditions, the open circuit voltage-time curve at each state of charge point, and the equivalent circuit;

[0022] The circuit parameters at each state of charge point and each temperature condition are respectively obtained based on the voltage rebound characteristic curve.

[0023] In one embodiment, the equivalent circuit includes a second-order equivalent circuit or a third-order equivalent circuit.

[0024] In a second aspect, the present application further provides a fault simulation method, comprising:

[0025] Constructing an energy storage system model using the above-mentioned energy storage system model construction method;

[0026] At least one of a short circuit fault test, an over-temperature fault test, and an electrical fault test is performed on the energy storage system model.

[0027] In a third aspect, the present application further provides a device for constructing an energy storage system model, wherein the energy storage system includes a plurality of connected single cells; the device includes:

[0028] A first model building module is used to build an equivalent circuit model of the single cell according to the operating experimental data of the single cell;

[0029] A model acquisition module, configured to acquire a heat generation model and a heat dissipation model of the energy storage system;

[0030] The second model building module is used to build the energy storage system model based on the heat generation model, the heat dissipation model, the equivalent circuit model and the preset assembly circuit.

[0031] In a fourth aspect, the present application further provides a computer device comprising a memory and a processor, wherein the memory stores a computer program, and the processor implements the steps of the above method when executing the computer program.

[0032] In a fifth aspect, the present application also provides a computer-readable storage medium having a computer program stored thereon, which implements the steps of the above method when executed by a processor.

[0033] The above-mentioned energy storage system model construction method, device and fault simulation method construct an equivalent circuit model of the single cell based on the operating experimental data of the single cell, obtain the heat generation model and heat dissipation model of the energy storage system, and construct the energy storage system model based on the heat generation model, heat dissipation model, equivalent circuit model and preset assembly circuit. Because the energy storage system model construction method in this application not only constructs the structural model of the energy storage system based on the equivalent circuit model of the single cell, but also takes into account the heat generation model and heat dissipation model of the energy storage system, it can accurately simulate the energy storage system and predict and analyze the heat dissipation effect before physical testing. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] Figure 1 A schematic flow chart of a method for building a model of an energy storage system in one embodiment;

[0035] Figure 2 is a second-order RC equivalent circuit diagram of a single battery in one embodiment;

[0036] Figure 3 A schematic diagram of a process for obtaining a heat dissipation model of an energy storage system in one embodiment;

[0037] Figure 4 A schematic diagram of a process for obtaining a heat generation model of an energy storage system in one embodiment;

[0038] Figure 5 is a state of charge-open circuit voltage curve in one embodiment;

[0039] Figure 6 An open circuit voltage-time curve at a state of charge point in one embodiment;

[0040] Figure 7 A schematic diagram of a process for constructing an equivalent circuit model of a single battery cell based on operating experimental data of the battery cell in one embodiment;

[0041] Figure 8 A schematic diagram of a process for obtaining circuit parameters according to an experimental data set in one embodiment;

[0042] Figure 9 is a rebound characteristic curve of a single battery in one embodiment;

[0043] Figure 10(a) to Figure 10(e) Graphs of the first polarized capacitor C1, the second polarized capacitor C2, the ohmic resistor R0, the first polarized resistor R1, and the second polarized resistor R2 corresponding to different SOC points under various temperature conditions in one embodiment;

[0044] Figure 11 A schematic block diagram of a device for constructing an energy storage system model in one embodiment;

[0045] Figure 12 FIG. 1 is a diagram showing the internal structure of a computer device in one embodiment. DETAILED DESCRIPTION

[0046] In order to make the purpose, technical solutions and advantages of this application more clear, the following further describes this application in detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only used to explain this application and are not intended to limit this application.

[0047] In one embodiment, Figure 1 The flow chart of the model construction method of the energy storage system shown provides a model construction method of the energy storage system. This embodiment uses the application of this method to the terminal as an example. It can be understood that this method can also be applied to the server, and can also be applied to the system including the terminal and the server, and is implemented through the interaction between the terminal and the server.

[0048] The energy storage system includes a plurality of connected single cells. Specifically, the plurality of single cells may be connected via series circuits and / or parallel circuits, such as an energy storage system consisting of 52 single cells connected in series or a containerized energy storage system consisting of 8 battery packs connected in series in a cluster and 10 clusters connected in parallel. It is understandable that, depending on the type of energy storage system, a plurality of single cells may also be connected to a battery management system. This embodiment does not limit the specific type and structure of the energy storage system. As long as the energy storage system includes a plurality of single cells, it may be applicable to the solution of this application, such as a large battery model, a PACK model, etc. In order to simplify system-level calculations and reduce the simulation calculation time of the constructed energy storage system model, this application uses the energy storage system model as an example of a large battery model.

[0049] The energy storage system model building method in this embodiment includes the following steps 102 to 106.

[0050] Step 102: construct an equivalent circuit model of the single cell according to the operating experimental data of the single cell.

[0051] Specifically, multiple experiments are conducted on the single battery cells to obtain the aforementioned operational test data, including high and low temperature charge and discharge rate experiments, HPPC (Hybrid Pulse Power Characterization) testing experiments, and energy storage performance experiments. It will be appreciated that the operational test data can be obtained based on a single experiment or on two or more experiments. The operational test data in this embodiment includes performance parameters or performance characterization curves related to the single battery cells.

[0052] The equivalent circuit model of a single cell includes the equivalent circuit of the single cell and various property parameters of the single cell. The equivalent circuit of a single cell can be a second-order RC (resistance-capacitance) equivalent circuit or a multi-order RC equivalent circuit (such as a third-order RC equivalent circuit). In order to facilitate data analysis and calculation accuracy, this application adopts the following Figure 2 The equivalent circuit model of the second-order RC equivalent circuit of the single cell shown is constructed, which includes an ohmic resistor R0 connected in series with two RC network structures (R1, R2, C1, C2). It is understood that in other embodiments, a simulation model of the single cell can also be constructed based on the electrochemical model of the single cell and the experimental data of the single cell operation, without limitation thereto.

[0053] Step 104: Obtain a heat generation model and a heat dissipation model of the energy storage system.

[0054] The heat generation model of an energy storage system accurately simulates and analyzes the thermal behavior of each cell in the system during the charge and discharge process. This model integrates multiple factors, including the electrochemical and thermophysical properties of the cell and the operating environment, to accurately simulate the thermal behavior of the energy storage system. Specifically, since cells are included in a cell, when deriving the heat dissipation model for the energy storage system, each cell can be treated as a point mass model to accumulate the heat generated by its internal resistance, thereby aggregating the power losses of each internal resistance into the thermal model.

[0055] The heat dissipation model of an energy storage system typically involves multiple thermal management methods to ensure that the battery operates within an appropriate temperature range to guarantee its performance and safety. These methods typically include heat conduction between cells, heat transfer between cells and the external environment, and heat exchange between cells and the cooling plate. Heat transfer between cells and the external environment is particularly important.

[0056] For example, Figure 3 The flowchart of obtaining the heat dissipation model of the energy storage system shown in FIG. 3 includes the following steps 302 to 308 .

[0057] Step 302: Obtain a heat transfer model between the battery cells in the single battery and the external environment.

[0058] Optionally, the above heat transfer model can be constructed using a convection module, where the heat transfer formula is: Q1 = k1A1 (T A -T B ), Q1 is the transferred heat, k1 is the convection heat transfer coefficient, A1 is the contact area, (T A -T B ) is the temperature difference between the battery cells within the single cell and the external environment. It will be appreciated that this formula assumes an ideal situation, where the heat transfer coefficient k1 is constant throughout the heat transfer process. In reality, k1 may vary with factors such as temperature and pressure. Furthermore, the formula assumes steady-state heat transfer, i.e., there is no heat loss or accumulation. In other embodiments, more complex models may be used to accurately describe the heat transfer process, particularly in situations involving unsteady-state or multidimensional heat transfer, which are not specifically limited here.

[0059] Step 304: Obtain a heat conduction model between the cells in the single battery.

[0060] Optionally, the above heat conduction model can be constructed by a conductive heat conduction module, wherein the heat transfer formula is: Q2 = k2A2 (T C -T D ) / D, Q2 is the heat transferred between battery cells, k2 is the thermal conductivity of the battery material, A2 is the surface area through which heat is transferred, and D is the distance through which heat is transferred or the thickness of the battery material. In the energy storage system, the establishment of the thermal conduction model needs to take into account the actual structure and working state of the battery cell. The battery cell generates heat during the charging and discharging process. This part of the heat needs to be transferred to the outside through the structure of the battery pack, and the role of the thermal management system may also be involved. The electrical conductivity of the battery material can accurately describe the thermal management effect of the battery. Therefore, the accurate thermal conductivity can be obtained according to the electrochemical and thermochemical processes of the battery under different boundary conditions, so that the constructed thermal conduction model is more accurate.

[0061] Step 306: Obtain a heat exchange model between the battery cells in the single battery and the water cooling plate.

[0062] The heat exchange model between the battery cell and the water-cooled plate in a single battery usually involves a complex heat transfer process, which includes multiple heat-conducting interfaces and fluid dynamics factors. For example, the heat exchange model can be obtained by the following steps: 1. Analyze the heat conduction path; such as clarifying the heat conduction path from the battery cell to the water-cooled plate, including the thermal resistance and thermal capacity characteristics of each link such as the battery cell, thermal conductive glue, module shell, and PACK lower box. 2. Establish a corresponding geometric model based on the actual geometric size and arrangement of the battery pack. 3. Build a simulation model of the liquid cooling system through simulation software such as AMESim, and explore the heat dissipation effect by simulating different working conditions. 4. Use experimental methods to monitor the temperature changes of the battery cell and the battery pack as a whole to verify the accuracy of the simulation model. Experiments can include temperature monitoring and thermal imaging under different working conditions.

[0063] Step 308: Acquire a heat dissipation model based on the heat transfer model, the heat conduction model, and the heat exchange model.

[0064] Obtaining a heat dissipation model for an energy storage system based on heat transfer models, heat conduction models, and heat exchange models can not only quickly predict the temperature response of the energy storage system under different operating conditions, thereby enabling evaluation and optimization of the heat dissipation solution during the design phase, but also optimize the performance of the energy storage system and enhance its reliability.

[0065] Alternatively, as Figure 4 The schematic diagram of the process of obtaining the heat generation model of the energy storage system is shown. Obtaining the heat generation model of the energy storage system includes the following steps 402 to 404.

[0066] Step 402: Obtain the heating power of each cell in the single battery.

[0067] Step 404 : constructing a heat generation model based on the heat generation power and the positional relationship between the single cells.

[0068] The heat generated by a battery cell directly affects the battery's temperature, while the positional relationship between cells affects the spread and distribution of heat. Therefore, building a heat generation model based on the heat generated and the positional relationship between individual cells can more accurately simulate the thermal behavior of individual cells under actual operating conditions.

[0069] Step 106 : constructing an energy storage system model based on the heat generation model, the heat dissipation model, the equivalent circuit model, and the preset assembly circuit.

[0070] In this embodiment, an equivalent circuit model of a single cell is constructed based on the operating experimental data of the single cell, a heat generation model and a heat dissipation model of the energy storage system are obtained, and an energy storage system model is constructed based on the heat generation model, the heat dissipation model, the equivalent circuit model, and the preset assembly circuit. Because the model construction method of the energy storage system in this application not only constructs the structural model of the energy storage system based on the equivalent circuit model of the single cell, but also takes into account the heat generation model and the heat dissipation model of the energy storage system, it can accurately simulate the energy storage system, predict and analyze the heat dissipation effect before physical testing, reduce the number and cost of experiments, and improve the safety of fault experiments.

[0071] In one embodiment, the operating experimental data includes state of charge-open circuit voltage curves under different temperature conditions, and open circuit voltage-time curves at each state of charge point. The different temperature conditions can be multiple 20°C to 50°C, such as 20°C, 25°C, 30°C, 35°C, 45°C, 50°C, etc. For example, the attached Figure 5 The figure shows the state of charge-open circuit voltage curve of a single cell with a nominal capacity of 280Ah. At 25℃, 35℃ and 45℃, the single cell is discharged with a 2C pulse current, then charge-adjusted, and then left to stand. The experiment is repeated until the battery is discharged. The terminal voltage is measured at the end of each charge adjustment and standing stage to obtain the state of charge-open circuit voltage curve. Figure 6 An open circuit voltage-time curve for a state of charge point is shown.

[0072] like Figure 7 The flowchart shown is for constructing an equivalent circuit model of a single battery cell according to the operating experimental data of the single battery cell. The process of constructing an equivalent circuit model of a single battery cell according to the operating experimental data of the single battery cell includes the following steps 702 to 706 .

[0073] Step 702: Establish an equivalent circuit of a single battery. The equivalent circuit has a plurality of circuit parameters to be identified. Figure 2 The structural diagram of the second-order RC equivalent circuit shown in the figure is as follows. If the equivalent circuit is a second-order RC equivalent circuit, its mathematical model is: V o =U oc -U1-U2-IR0;I=U1 / R1+C1dU1 / d t I = U2 / R2+C2dU2 / dt, the corresponding circuit parameters to be identified include the ohmic resistance R0, the first polarized resistance R1, the second polarized resistance R2, the first polarized capacitor C1 and the second polarized capacitor C2. oc It is a constant voltage source. When it discharges at a constant current, The voltage drop across the ohmic resistor R0 causes V o The change of Based on the nonlinear characteristics of the circuit, the problem of solving the five parameters is transformed into a nonlinear optimization problem. For any parameters X = R1, R2, C1, C2, there is a unique Vo(t) corresponding to any time t: Vo(t) is the actual output voltage, and a nonlinear least squares optimization model can be constructed: minFX=Uo(t)-Vo(t).stX(1)>0,X(2)>0,X(3)>0,X(4)>0,t>0.

[0074] Step 704 : Acquire an experimental data set of a single battery. The experimental data set includes state of charge-open circuit voltage curves under different temperature conditions and open circuit voltage-time curves at each state of charge point.

[0075] Step 706 : Obtain various circuit parameters according to the experimental data set to generate an equivalent circuit model.

[0076] For example, Figure 8 The flowchart of obtaining various circuit parameters according to the experimental data set shown in FIG. 8 includes the following steps 802 to 804 .

[0077] Step 802 : Obtain a voltage rebound characteristic curve of a single battery based on the state of charge-open circuit voltage curves under different temperature conditions, the open circuit voltage-time curves at each state of charge point, and the equivalent circuit.

[0078] like Figure 9 The rebound characteristic curve of the single battery shown in the figure, where point A is the battery discharge moment and point C is the discharge end moment. In the AB segment, the terminal voltage drops rapidly due to the ohmic voltage R0 at the beginning of discharge. In the BC segment, the terminal voltage drops slowly due to the influence of the internal polarization characteristics of the battery, and is approximately a zero-state response: The CD segment is the reverse process of the AB segment; the DE segment is the rebound characteristic of the single cell. Point E represents the single cell reaching a stable state. The process is approximately the zero-input response of the circuit: Therefore, R0 can be solved based on the AB and CD segments:

[0079] Step 804 : Obtain circuit parameters at each state of charge point and each temperature condition based on the voltage rebound characteristic curve.

[0080] A nonlinear least squares optimization model is established based on the voltage rebound characteristic curve to identify the R1, R2, C1, and C2 parameters corresponding to each SOC point. The relationship between R and C can be obtained according to the above formula: According to the experimental data, the relationship between R and C is used to determine the parameter values ​​at different SOC points. Through offline identification, the following can be obtained: Figure 10(a) to Figure 10(e) The graphs of the first polarized capacitor C1, the second polarized capacitor C2, the ohmic resistor R0, the first polarized resistor R1, and the second polarized resistor R2 corresponding to different SOC points under various temperature conditions are shown. Furthermore, the identified parameter values, including the model parameters corresponding to each temperature point and SOC point, can be summarized into a table of R0(SOC, T), R1(SOC, T), R2(SOC, T), C1(SOC, T), and C2(SOC, T) to complete the final parameter identification.

[0081] In one embodiment, the present application also provides a fault simulation method, which includes the following steps: constructing an energy storage system model using the energy storage system model construction method in any of the above embodiments; performing at least one of a short circuit fault test, an overtemperature fault test, and an electrical fault test on the energy storage system model.

[0082] It can be understood that since the fault simulation method in this embodiment includes constructing an energy storage system model using the energy storage system model construction method in any of the above embodiments, performing at least one of a short-circuit fault test, an overtemperature fault test, and an electrical fault test on the energy storage system model based on the model can effectively reduce the high cost of system experiments and ensure safety.

[0083] It should be understood that, although the various steps in the flowcharts involved in the various embodiments described above are displayed in sequence according to the instructions of the arrows, these steps are not necessarily executed in sequence in the order indicated by the arrows. Unless otherwise specified herein, there is no strict order restriction on the execution of these steps, and these steps can be executed in other orders. Moreover, at least a portion of the steps in the flowcharts involved in the various embodiments described above can include multiple steps or multiple stages, and these steps or stages are not necessarily executed and completed at the same time, but can be executed at different times, and the execution order of these steps or stages is not necessarily to be carried out in sequence, but can be executed in turn or alternately with other steps or at least a portion of steps or stages in other steps.

[0084] Based on the same inventive concept, embodiments of the present application also provide a device for constructing an energy storage system model for implementing the aforementioned method for constructing an energy storage system model. The solution provided by this device is similar to the solution described in the aforementioned method. Therefore, the specific limitations of one or more embodiments of the device for constructing an energy storage system model provided below can be found in the limitations of the method for constructing an energy storage system model described above and will not be further elaborated here.

[0085] In one embodiment, this embodiment further provides a device 1100 for constructing an energy storage system model, wherein the energy storage system includes a plurality of connected single cells. Figure 11 The schematic block diagram of the energy storage system model construction apparatus 1100 is shown. In this embodiment, the energy storage system model construction apparatus 1100 includes a first model construction module 1110, a model acquisition module 1120, and a second model construction module 1130. The first model construction module 1110 is configured to construct an equivalent circuit model of a single cell based on experimental operating data of the single cell. The model acquisition module 1120 is configured to obtain a heat generation model and a heat dissipation model of the energy storage system. The second model construction module 1130 is configured to construct an energy storage system model based on the heat generation model, the heat dissipation model, the equivalent circuit model, and a preset assembly circuit.

[0086] In one embodiment, the model acquisition module is also used to obtain a heat transfer model between the battery cells in a single battery and the external environment; obtain a heat conduction model between the battery cells in a single battery; obtain a heat exchange model between the battery cells in a single battery and a water cooling plate; and obtain a heat dissipation model based on the heat transfer model, the heat conduction model, and the heat exchange model.

[0087] In one embodiment, the model acquisition module is further used to acquire the heat generation power of each cell in the single battery; and to construct a heat generation model based on the heat generation power and the positional relationship between each single battery.

[0088] In one embodiment, the operational experimental data includes state-of-charge (SOC)-open-circuit voltage (OCV) curves under different temperature conditions and open-circuit voltage-time curves at each SOC point. The first model building module is further configured to establish an equivalent circuit for the single cell battery, the equivalent circuit having multiple circuit parameters to be identified; obtain an experimental data set for the single cell battery, the experimental data set including the SOC-open-circuit voltage (OCV) curves under different temperature conditions and open-circuit voltage-time curves at each SOC point; and obtain the circuit parameters based on the experimental data set to generate an equivalent circuit model.

[0089] The equivalent circuit includes a second-order equivalent circuit or a third-order equivalent circuit.

[0090] In one embodiment, the first model building module is further used to obtain the voltage rebound characteristic curve of the single cell based on the state of charge-open circuit voltage curve under different temperature conditions, the open circuit voltage-time curve at each state of charge point and the equivalent circuit; and obtain the circuit parameters at each state of charge point and each temperature condition based on the voltage rebound characteristic curve.

[0091] Each module in the above-mentioned energy storage system model construction device can be implemented in whole or in part through software, hardware, or a combination thereof. Each of the above modules can be embedded in or independent of a processor in a computer device in hardware form, or can be stored in a computer device memory in software form, so that the processor can call and execute the corresponding operations of each module.

[0092] In one embodiment, a computer device is provided. The computer device may be a terminal, and its internal structure diagram may be as follows: Figure 12 As shown. The computer device includes a processor, a memory, a communication interface, a display screen and an input device connected via a system bus. The processor of the computer device is used to provide computing and control capabilities. The memory of the computer device includes a non-volatile storage medium and an internal memory. The non-volatile storage medium stores an operating system and a computer program. The internal memory provides an environment for the operation of the operating system and the computer program in the non-volatile storage medium. The communication interface of the computer device is used to communicate with an external terminal in a wired or wireless manner, and the wireless manner can be achieved through WIFI, a mobile cellular network, NFC (near field communication) or other technologies. When the computer program is executed by the processor, a method for constructing an energy storage system model is implemented. The display screen of the computer device can be a liquid crystal display screen or an electronic ink display screen, and the input device of the computer device can be a touch layer covering the display screen, or a button, trackball or touchpad provided on the computer device housing, or an external keyboard, touchpad or mouse.

[0093] Those skilled in the art will understand that Figure 12 The structure shown in the figure is only a block diagram of a part of the structure related to the solution of the present application, and does not constitute a limitation on the computer device to which the solution of the present application is applied. The specific computer device may include more or fewer components than shown in the figure, or combine certain components, or have a different component arrangement.

[0094] In one embodiment, a computer device is provided, including a memory and a processor. The memory stores a computer program, and the processor implements the steps in the above method embodiments when executing the computer program.

[0095] In one embodiment, a computer program product is provided, including a computer program, which implements the steps in the above method embodiments when executed by a processor.

[0096] Those skilled in the art will appreciate that all or part of the processes in the above-mentioned embodiment methods can be implemented by instructing the relevant hardware through a computer program, and the computer program can be stored in a non-volatile computer-readable storage medium. When the computer program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, any reference to memory, database or other media used in the embodiments provided in this application may include at least one of non-volatile and volatile memory. Non-volatile memory may include read-only memory (ROM), magnetic tape, floppy disk, flash memory, optical memory, high-density embedded non-volatile memory, resistive random access memory (ReRAM), magnetic random access memory (MRAM), ferroelectric random access memory (FRAM), phase change memory (PCM), graphene memory, etc. Volatile memory may include random access memory (RAM) or external cache memory, etc. By way of illustration and not limitation, RAM can be in various forms, such as static random access memory (SRAM) or dynamic random access memory (DRAM). The database involved in the various embodiments provided herein may include at least one of a relational database and a non-relational database. Non-relational databases may include, but are not limited to, distributed databases based on blockchains. The processor involved in the various embodiments provided herein may be, but are not limited to, a general-purpose processor, a central processing unit, a graphics processing unit, a digital signal processor, a programmable logic unit, a data processing logic unit based on quantum computing, and the like.

[0097] The technical features of the above embodiments can be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0098] The above-described embodiments merely represent several implementation methods of the present application. While the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the present application. It should be noted that a person of ordinary skill in the art may make various modifications and improvements without departing from the spirit of the present application, and these modifications and improvements fall within the scope of protection of the present application. Therefore, the scope of protection of the present application shall be determined by the appended claims.

Claims

1. A method for constructing an energy storage system model, characterized in that: The energy storage system includes a plurality of connected single batteries; the method includes: constructing an equivalent circuit model of the single cell based on operating experimental data of the single cell; the operating experimental data including state-of-charge-open-circuit voltage (SOC-OCV) curves under different temperature conditions, open-circuit voltage-time curves at each state-of-charge point, and circuit parameters identified based on a voltage rebound characteristic curve; Obtaining a heat generation model and a heat dissipation model of the energy storage system; Constructing the energy storage system model based on the heat generation model, the heat dissipation model, the equivalent circuit model and the preset assembly circuit; Wherein, obtaining the heat dissipation model of the energy storage system includes: Obtaining a heat transfer model between the battery cells in the single battery and the external environment; Obtain a heat conduction model between the cells in the single battery; the heat transfer formula in the heat conduction model between the cells is: Q2 = k2A2 (T C -T D ) / D, Q2 is the heat transferred between the battery cells, k2 is the thermal conductivity of the battery material, A2 is the surface area through which the heat is transferred, and D is the distance of heat transfer or the thickness of the battery material; obtaining a heat exchange model between the battery cells in the single battery and the water cooling plate; The heat dissipation model is acquired based on the heat transfer model, the heat conduction model, and the heat exchange model.

2. The method for constructing an energy storage system model according to claim 1, wherein: Obtaining a heat generation model of the energy storage system includes: Obtaining the heating power of each cell in the single battery; The heat generation model is constructed based on the heat generation power and the positional relationship between the single cells.

3. The method for constructing an energy storage system model according to claim 1, wherein: Constructing an equivalent circuit model of a single single cell according to the operating experimental data of the single cell, including: Establishing an equivalent circuit of the single battery, wherein the equivalent circuit has a plurality of circuit parameters to be identified; Acquire an experimental data set of the single battery, the experimental data set comprising the state of charge-open circuit voltage curve under different temperature conditions and the open circuit voltage-time curve at each state of charge point; The circuit parameters are obtained according to the experimental data set to generate the equivalent circuit model.

4. The method for constructing an energy storage system model according to claim 3, wherein: Acquiring each of the circuit parameters according to the experimental data set includes: Obtaining a voltage rebound characteristic curve of the single battery based on the state of charge-open circuit voltage curve under the different temperature conditions, the open circuit voltage-time curve at each state of charge point, and the equivalent circuit; The circuit parameters at each state of charge point and each temperature condition are respectively obtained based on the voltage rebound characteristic curve.

5. The method for constructing an energy storage system model according to claim 3 or 4, characterized in that: The equivalent circuit includes a second-order equivalent circuit or a third-order equivalent circuit.

6. A fault simulation method, characterized in that: include: Constructing an energy storage system model using the energy storage system model construction method according to any one of claims 1 to 5; At least one of a short circuit fault test, an over-temperature fault test, and an electrical fault test is performed on the energy storage system model.

7. A device for constructing an energy storage system model, characterized in that: The energy storage system includes a plurality of connected single batteries; the device includes: a first model building module for building an equivalent circuit model of the single cell based on operating experimental data of the single cell; the operating experimental data including state-of-charge-open-circuit voltage (SOC-OCV) curves under different temperature conditions, open-circuit voltage-time curves at each state-of-charge point, and circuit parameters identified based on a voltage rebound characteristic curve; A model acquisition module, configured to acquire a heat generation model and a heat dissipation model of the energy storage system; A second model construction module is used to construct the energy storage system model based on the heat generation model, the heat dissipation model, the equivalent circuit model and the preset assembly circuit; Wherein, obtaining the heat dissipation model of the energy storage system includes: Obtaining a heat transfer model between the battery cells in the single battery and the external environment; Obtain a heat conduction model between the cells in the single battery; the heat transfer formula in the heat conduction model between the cells is: Q2 = k2A2 (T C -T D ) / D, Q2 is the heat transferred between the cells, k2 is the thermal conductivity of the battery material, A2 is the surface area through which the heat is transferred, and D is the distance the heat is transferred or the thickness of the battery material; Obtaining a heat exchange model between the battery cells in the single battery and the water cooling plate; The heat dissipation model is acquired based on the heat transfer model, the heat conduction model, and the heat exchange model.

8. A computer device comprising a memory and a processor, wherein the memory stores a computer program, wherein: When the processor executes the computer program, the steps of the method according to any one of claims 1 to 5 are implemented.

9. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the steps of the method according to any one of claims 1 to 5 are implemented.

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