Power battery pre-charging fault diagnosis method and system, electronic equipment and storage medium

Abstract

The invention discloses a power battery pre-charging fault diagnosis method and system, electronic equipment and a storage medium, and relates to the field of diagnosis prediction, and the method comprises the steps: obtaining the voltage at the rear end of a pre-charging loop; calculating a rear end voltage change rate of the pre-charging loop; obtaining a pre-charging resistance temperature; predicting theoretical temperature rise data based on preset thermal model parameters; and performing fault diagnosis based on the predicted theoretical temperature rise data and the adopted temperature rise data. According to the scheme, rich fault diagnosis information is obtained, electrical performance related faults such as pre-charging open circuit faults and pre-charging short circuit faults can be diagnosed, and thermal performance related faults such as pre-charging resistor overheating faults can also be diagnosed. Through pre-diagnosis of a pre-charging fault, prediction of a resistor temperature rise by using a thermal model, and comparison with an actual temperature rise, when a pre-charging safety risk occurs, early warning is performed in advance, and the risk is effectively avoided.

Description

Technical Field

[0001] This application relates to the field of diagnostic prediction, and in particular to a method for diagnosing precharge faults in power batteries, a system for diagnosing precharge faults in power batteries, electronic devices, storage media, and a diagnostic prediction platform. Background Technology

[0002] In the integrated high-voltage power distribution scheme of power battery systems, the pre-charge circuit design can prevent inrush current from occurring at the moment the high-voltage circuit closes, which could damage the load and thus pose a safety risk. However, if a short circuit or open circuit fault occurs during pre-charge and is not promptly detected and addressed, the aforementioned risks can also occur. Therefore, fault diagnosis of the pre-charge circuit is particularly important.

[0003] CN120552611A uses a preset mapping relationship between pre-charge voltage and pre-charge time to determine a fault when the absolute value of the pre-charge voltage does not reach the preset value. However, fluctuations in voltage or unreasonable threshold settings can lead to false fault determinations. This application uses the voltage change rate to consider the relative trend of voltage change, which is less affected by the absolute voltage.

[0004] CN111289870B and CN115792448A use multi-segment precharge voltage difference for precharge fault determination, which is cumbersome. This application proposes a new method that uses the differential formula to obtain the maximum voltage change rate, and combines it with the resistance temperature rise and heat accumulation threshold for joint determination, which is simple and reliable. Summary of the Invention

[0005] The purpose of this invention is to provide a method for diagnosing pre-charge faults in power batteries, a system for diagnosing pre-charge faults in power batteries, an electronic device, a storage medium, and a diagnostic prediction platform, thereby solving at least one of a number of technical problems.

[0006] 1. The problem of false fault diagnosis caused by voltage fluctuations or unreasonable threshold settings; 2. The problem of overly complicated pre-charge fault diagnosis based on the voltage difference of multiple pre-charge voltages.

[0007] This invention provides the following solution:

[0008] According to a first aspect of the present invention, a method for diagnosing pre-charge faults in a power battery is provided, comprising:

[0009] Step A1: Obtain the voltage at the back end of the pre-charge circuit;

[0010] Step A2: Calculate the rate of change of voltage at the back end of the pre-charge circuit;

[0011] Step A3: Obtain the pre-charge resistance temperature;

[0012] Step A4: Based on the preset thermal model parameters, predict the theoretical temperature rise data;

[0013] Step A5: Based on the predicted theoretical temperature rise data and using the temperature rise data, perform fault diagnosis.

[0014] Furthermore, it also includes:

[0015] Step S1, obtain the formula for calculating the theoretical precharge voltage as a function of time: A model of the pre-charge voltage changing over time was established.

[0016] Differentiating this formula yields the formula for the rate of change of voltage. ;

[0017] Determine the maximum rate of voltage change at the instant precharge begins. ;

[0018] Among them, the battery voltage is The pre-charge resistance is The bus capacitance is Precharge time is The precharge voltage is The precharge voltage change rate is .

[0019] Furthermore, it also includes:

[0020] Step S2: After pre-charging begins, the voltage at the back end of the pre-charging circuit is sampled in real time.

[0021] Calculate the real-time voltage change rate using the voltage change rate formula;

[0022] Step S3: Perform fault determination based on real-time voltage change rate.

[0023] If the rate of change of voltage or voltage change rate And battery voltage If the condition is not met, it is determined to be a precharge short circuit fault. Custom coefficients;

[0024] If the rate of change of voltage The fault was determined to be a precharge circuit breaker failure.

[0025] Furthermore, it also includes:

[0026] Step S4: If the fault determination in step 3 is not triggered, calculate the cumulative heat of the pre-charge resistor. Simultaneously sample the actual temperature of the pre-charge resistor. ;

[0027] The theoretical temperature rise of the pre-charge resistance is predicted using a thermal model. .

[0028] Furthermore, it also includes:

[0029] Step S5, if, If so, a pre-charge resistor temperature overheat warning will be issued;

[0030] like, Then, further determine whether the conditions are met simultaneously. and ;

[0031] If the conditions are not met, a pre-charge overheating fault will be reported.

[0032] If the conditions are met, then the pre-charging is considered complete.

[0033] Furthermore, it also includes:

[0034] Step S6: After the pre-charging is completed, continuously observe whether the temperature of the pre-charging resistor rises;

[0035] If the temperature of the pre-charge resistor continues to rise beyond the preset range after the pre-charge is completed, the pre-charge relay is determined to be stuck.

[0036] According to a second aspect of the present invention, a power battery precharge fault diagnosis system is provided, comprising:

[0037] Voltage sampling module, used to acquire the voltage at the back end of the precharge circuit;

[0038] The voltage change rate calculation module is used to calculate the voltage change rate at the back end of the precharge circuit.

[0039] Temperature sampling module, used to obtain the temperature of the pre-charge resistor;

[0040] The thermal prediction module is used to predict theoretical temperature rise data based on preset thermal model parameters;

[0041] The fault diagnosis module is used to diagnose faults based on predicted theoretical temperature rise data and actual temperature rise data.

[0042] According to a third aspect of the present invention, an electronic device is provided, comprising: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other via the communication bus;

[0043] The memory stores a computer program, which, when executed by the processor, causes the processor to perform steps such as a method for diagnosing pre-charge faults in a power battery.

[0044] According to a fourth aspect of the present invention, a computer-readable storage medium is provided, storing a computer program executable by an electronic device, which, when run on the electronic device, causes the electronic device to perform steps such as a power battery precharge fault diagnosis method.

[0045] According to a fifth aspect of the present invention, a diagnostic prediction platform is provided, comprising:

[0046] Electronic equipment used to implement steps such as methods for diagnosing precharge faults in power batteries;

[0047] The processor runs programs, and when the programs are running, they execute steps such as power battery precharge fault diagnosis methods based on data output from electronic devices.

[0048] Storage medium used to store programs that, when running, perform steps such as a power battery precharge fault diagnosis method on data output from electronic devices.

[0049] The above solution achieves the following beneficial technical effects:

[0050] This application uses three methods—pre-charge voltage change rate, pre-charge resistance temperature rise, and pre-charge resistance heat accumulation—to diagnose pre-charge faults. The diagnosis is fast and reliable.

[0051] This application, through its rich fault diagnosis information, can diagnose not only electrical performance-related faults, such as precharge open circuit faults and precharge short circuit faults, but also thermal performance-related faults, such as precharge resistor overheating faults.

[0052] This application uses a thermal model to predict the resistance temperature rise by pre-diagnosing pre-charge faults and comparing it with the actual temperature rise. This provides an early warning when a pre-charge safety risk occurs, effectively avoiding the risk.

[0053] This application continuously monitors whether the temperature of the pre-charge resistor rises after the pre-charge is completed, and determines the sticking of the pre-charge relay from the perspective of thermal performance. It directly monitors the ultimate hazard of overheating that may lead to fire or hardware damage, thus achieving a true safety warning. Attached Figure Description

[0054] Figure 1 This is a flowchart of a power battery precharge fault diagnosis method provided by one or more embodiments of the present invention.

[0055] Figure 2 This is a structural diagram of a power battery precharge fault diagnosis system provided in one or more embodiments of the present invention.

[0056] Figure 3 This is a schematic diagram of a precharge circuit fault diagnosis process provided in a specific embodiment of the present invention.

[0057] Figure 4 This is a block diagram of an electronic device structure for a power battery precharge fault diagnosis method provided in one or more embodiments of the present invention. Detailed Implementation

[0058] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0059] Figure 1 This is a flowchart of a power battery precharge fault diagnosis method provided by one or more embodiments of the present invention.

[0060] like Figure 1 The power battery precharge fault diagnosis method shown includes:

[0061] Obtain the voltage at the back end of the precharge circuit;

[0062] Calculate the rate of change of voltage at the back end of the precharge circuit;

[0063] Obtain the pre-charge resistance temperature;

[0064] Based on preset thermal model parameters, predict theoretical temperature rise data;

[0065] Fault diagnosis is performed based on predicted theoretical temperature rise data and by using temperature rise data.

[0066] In this embodiment, it also includes:

[0067] Step S1, obtain the formula for calculating the theoretical precharge voltage as a function of time: A model of the pre-charge voltage changing over time was established.

[0068] Differentiating this formula yields the formula for the rate of change of voltage. ;

[0069] Determine the maximum rate of voltage change at the instant precharge begins. ;

[0070] Among them, the battery voltage is The pre-charge resistance is The bus capacitance is Precharge time is The precharge voltage is The precharge voltage change rate is .

[0071] In this embodiment, it also includes:

[0072] Step S2: After pre-charging begins, the voltage at the back end of the pre-charging circuit is sampled in real time.

[0073] Calculate the real-time voltage change rate using the voltage change rate formula;

[0074] Step S3: Perform fault determination based on real-time voltage change rate.

[0075] If the rate of change of voltage or voltage change rate And battery voltage If the condition is not met, it is determined to be a precharge short circuit fault. Custom coefficients;

[0076] If the rate of change of voltage The fault was determined to be a precharge circuit breaker failure.

[0077] In this embodiment, it also includes:

[0078] Step S4: If the fault determination in step 3 is not triggered, calculate the cumulative heat of the pre-charge resistor. Simultaneously sample the actual temperature of the pre-charge resistor. ;

[0079] The theoretical temperature rise of the pre-charge resistance is predicted using a thermal model. .

[0080] In this embodiment, it also includes:

[0081] Step S5, if, If so, a pre-charge resistor temperature overheat warning will be issued;

[0082] like, Then, further determine whether the conditions are met simultaneously. and ;

[0083] If the conditions are not met, a pre-charge overheating fault will be reported.

[0084] If the conditions are met, then the pre-charging is considered complete.

[0085] In this embodiment, it also includes:

[0086] Step S6: After the pre-charging is completed, continuously observe whether the temperature of the pre-charging resistor rises;

[0087] If the temperature of the pre-charge resistor continues to rise beyond the preset range after the pre-charge is completed, the pre-charge relay is determined to be stuck.

[0088] Figure 2 This is a structural diagram of a power battery precharge fault diagnosis system provided in one or more embodiments of the present invention.

[0089] like Figure 2 The power battery precharge fault diagnosis system shown includes:

[0090] Voltage sampling module, used to acquire the voltage at the back end of the precharge circuit;

[0091] The voltage change rate calculation module is used to calculate the voltage change rate at the back end of the precharge circuit.

[0092] Temperature sampling module, used to obtain the temperature of the pre-charge resistor;

[0093] The thermal prediction module is used to predict theoretical temperature rise data based on preset thermal model parameters;

[0094] The fault diagnosis module is used to diagnose faults based on predicted theoretical temperature rise data and actual temperature rise data.

[0095] It is worth noting that although this system / device only discloses the above-mentioned modules / units, it does not mean that this system / device is limited to the above-mentioned basic functional modules. On the contrary, what this invention intends to express is that, based on the above-mentioned basic functional modules, those skilled in the art can add one or more functional modules in combination with the prior art to form an infinite number of embodiments or technical solutions. That is to say, this system is open rather than closed. It cannot be assumed that the scope of protection of the claims of this invention is limited to the above-disclosed basic functional modules just because this embodiment only discloses a few basic functional modules.

[0096] In one specific embodiment, a precharge circuit fault diagnosis device is disclosed, comprising:

[0097] Voltage sampling module: Acquires the voltage at the back end of the pre-charge circuit;

[0098] Voltage change rate calculation module: Calculates the voltage change rate at the back end of the precharge circuit;

[0099] Temperature sampling module: Collects the temperature of the pre-charged resistor;

[0100] Thermal prediction module: Stores thermal model parameters and predicts theoretical temperature rise data;

[0101] Fault diagnosis module: Determines whether the precharge relay is stuck.

[0102] In one specific embodiment, a precharge circuit fault diagnosis method is disclosed, comprising:

[0103] The formula for calculating the theoretical precharge voltage change over time is: U_cap(t) = U_bat * (1 - e^(-t / (R*C)));

[0104] Taking the derivative of the above formula, we can obtain the voltage change rate (slope): dU_cap(t) / dt=(U_bat / (R*C))*e^(-t / (R*C));

[0105] At the instant the pre-charge begins (t=0), the voltage change rate is at its maximum, denoted as dUmax=U_bat / (R*C).

[0106] (Battery voltage is U_bat, pre-charge resistance is R, bus capacitance is C, pre-charge time is t)

[0107] After pre-charging begins, the voltage at the back end of the pre-charging circuit is sampled and the voltage change rate is calculated in real time;

[0108] If the voltage change rate is <0 or (voltage change rate = 0 and voltage ≤ α*U_cap), then a pre-charge short circuit fault is determined, and the pre-charge fails.

[0109] If the rate of change of voltage is greater than dUmax, then a pre-charge circuit breaker fault is determined, and the process enters the pre-charge fault state.

[0110] If the pre-charge short circuit fault and pre-charge open circuit fault are not triggered, continue to determine whether the pre-charge completion conditions are met. If they are met, enter the pre-charge completion state and end the pre-charge process. If they are not met, enter the pre-charge fault state.

[0111] Calculate the cumulative heat Q when the pre-charge resistor carries current: Q = t * (U_bat – U 采集 )2 / R;

[0112] Sampling Predicted Resistance Actual Temperature T 采样 Simultaneously, the theoretical temperature rise T of the pre-charge resistance is predicted through the thermal prediction module. 预测 If T 采样 ≤T 预测 Proceed to the next step of the process; if the conditions are not met, issue a warning for excessively high resistance temperature.

[0113] Determine whether the following conditions are met simultaneously: ①T 采样 If the temperature threshold is ≤ and the heat threshold is ≤, proceed to step 5; otherwise, report a pre-charge over-temperature fault and end the pre-charge.

[0114] After the pre-charge is completed, continuously monitor whether the temperature of the pre-charge resistor rises to determine whether the pre-charge relay is stuck.

[0115] Where dUmax is the maximum voltage change rate; U_cap(t) is the precharge voltage; dU_cap(t) is the precharge voltage change rate; dUmax is the maximum precharge voltage change rate; α is a user-defined coefficient; and Q is the accumulated heat through the precharge resistor.

[0116] Figure 4 This is a block diagram of an electronic device structure for a power battery precharge fault diagnosis method provided in one or more embodiments of the present invention.

[0117] like Figure 4 As shown, this application provides an electronic device, including: a processor, a communication interface, a memory, and a communication bus, wherein the processor, the communication interface, and the memory communicate with each other through the communication bus;

[0118] The memory stores a computer program, which, when executed by the processor, causes the processor to perform the steps of a power battery precharge fault diagnosis method.

[0119] This application also provides a computer-readable storage medium storing a computer program executable by an electronic device, which, when run on the electronic device, causes the electronic device to perform the steps of a power battery precharge fault diagnosis method.

[0120] This application also provides a diagnostic prediction platform, including:

[0121] Electronic equipment, used to implement a method for diagnosing pre-charge faults in power batteries;

[0122] The processor runs a program, and when the program runs, it executes the steps of the power battery precharge fault diagnosis method based on the data output from the electronic device.

[0123] Storage medium for storing programs that, when running, execute steps of a power battery precharge fault diagnosis method based on data output from electronic devices.

[0124] The communication bus mentioned in the above electronic devices can be a Peripheral Component Interconnect (PCI) bus or an Extended Industry Standard Architecture (EISA) bus, etc. This communication bus can be divided into address bus, data bus, control bus, etc. For ease of illustration, only one thick line is used to represent it in the diagram, but this does not indicate that there is only one bus or one type of bus.

[0125] The electronic device comprises a hardware layer, an operating system layer running on top of the hardware layer, and an application layer running on the operating system. The hardware layer includes hardware such as a central processing unit (CPU), a memory management unit (MMU), and memory. The operating system can be any one or more computer operating systems that control the electronic device through processes, such as Linux, Unix, Android, iOS, or Windows. Furthermore, in this embodiment of the invention, the electronic device can be a smartphone, tablet computer, or other handheld device, or a desktop computer, portable computer, or other electronic device; there is no particular limitation in this embodiment.

[0126] In this embodiment of the invention, the executing entity for electronic device control can be an electronic device itself, or a functional module within an electronic device capable of calling and executing a program. The electronic device can obtain the firmware corresponding to the storage medium. This firmware is provided by the supplier, and different storage media may have the same or different firmware; no limitation is made here. After obtaining the firmware corresponding to the storage medium, the electronic device can write this firmware into the storage medium; specifically, it burns the firmware corresponding to the storage medium into the storage medium. The process of burning the firmware into the storage medium can be implemented using existing technology, and will not be elaborated upon in this embodiment of the invention.

[0127] Electronic devices can also obtain reset commands corresponding to the storage media. The reset commands corresponding to the storage media are provided by the supplier. The reset commands corresponding to different storage media can be the same or different, and no restrictions are imposed here.

[0128] At this time, the storage medium of the electronic device is a storage medium on which the corresponding firmware has been written. The electronic device can respond to the reset command corresponding to the storage medium on which the corresponding firmware has been written, thereby resetting the storage medium on which the corresponding firmware has been written according to the reset command. The process of resetting the storage medium according to the reset command can be implemented by existing technology and will not be described in detail in this embodiment of the invention.

[0129] For ease of description, the above devices are described separately by function as various units and modules. Of course, in implementing this application, the functions of each unit and module can be implemented in one or more software and / or hardware.

[0130] It will be understood by those skilled in the art that, unless otherwise defined, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. It should also be understood that terms such as those defined in general dictionaries should be understood to have the meaning consistent with their meaning in the context of the prior art, and should not be interpreted in an idealized or overly formal sense unless specifically defined.

[0131] For the sake of simplicity, the method embodiments are described as a series of actions. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the described order of actions, because according to the embodiments of the present invention, some steps can be performed in other orders or simultaneously. Furthermore, those skilled in the art should also understand that the embodiments described in the specification are preferred embodiments, and the actions involved are not necessarily essential to the embodiments of the present invention.

[0132] As can be seen from the above description of the embodiments, those skilled in the art can clearly understand that this application can be implemented by means of software plus necessary general-purpose hardware platforms. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product can be stored in a storage medium, such as ROM / RAM, magnetic disk, optical disk, etc., and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute the methods described in various embodiments or some parts of the embodiments of this application.

[0133] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for diagnosing pre-charge faults in power batteries, characterized in that, The method for diagnosing pre-charge faults in power batteries includes: Obtain the voltage at the back end of the precharge circuit; Calculate the rate of change of voltage at the back end of the precharge circuit; Obtain the pre-charge resistance temperature; Based on preset thermal model parameters, predict theoretical temperature rise data; Fault diagnosis is performed based on predicted theoretical temperature rise data and by using temperature rise data.

2. The method for diagnosing pre-charge faults in power batteries according to claim 1, characterized in that, Also includes: Step S1, obtain the formula for calculating the theoretical precharge voltage as a function of time: A model of the pre-charge voltage changing over time was established; Differentiating this formula yields the formula for the rate of change of voltage. ; Determine the maximum rate of voltage change at the instant precharge begins. ; Among them, the battery voltage is The pre-charge resistance is The bus capacitance is Precharge time is The precharge voltage is The precharge voltage change rate is .

3. The method for diagnosing pre-charge faults in a power battery according to claim 2, characterized in that, Also includes: Step S2: After pre-charging begins, the voltage at the back end of the pre-charging circuit is sampled in real time. Calculate the real-time voltage change rate using the voltage change rate formula; Step S3: Perform fault determination based on real-time voltage change rate. If the rate of change of voltage or voltage change rate And battery voltage If the condition is not met, it is determined to be a precharge short circuit fault. Custom coefficients; If the rate of change of voltage The fault was determined to be a precharge circuit breaker failure.

4. The method for diagnosing pre-charge faults in a power battery according to claim 3, characterized in that, Also includes: Step S4: If the fault determination in step 3 is not triggered, calculate the cumulative heat of the pre-charge resistor. Simultaneously sample the actual temperature of the pre-charge resistor. ; The theoretical temperature rise of the pre-charge resistance is predicted using a thermal model. .

5. The method for diagnosing pre-charge faults in power batteries according to claim 4, characterized in that, Also includes: Step S5, if, If so, a pre-charge resistor temperature overheat warning will be issued; like, Then, further determine whether the conditions are met simultaneously. and ; If the conditions are not met, a pre-charge overheating fault will be reported. If the conditions are met, then the pre-charging is considered complete.

6. The method for diagnosing pre-charge faults in a power battery according to claim 5, characterized in that, Also includes: Step S6: After the pre-charging is completed, continuously observe whether the temperature of the pre-charging resistor rises; If the temperature of the pre-charge resistor continues to rise beyond the preset range after the pre-charge is completed, the pre-charge relay is determined to be stuck.

7. A power battery precharge fault diagnosis system, characterized in that, The power battery precharge fault diagnosis system includes: Voltage sampling module, used to acquire the voltage at the back end of the precharge circuit; The voltage change rate calculation module is used to calculate the voltage change rate at the back end of the precharge circuit. Temperature sampling module, used to obtain the temperature of the pre-charge resistor; The thermal prediction module is used to predict theoretical temperature rise data based on preset thermal model parameters; The fault diagnosis module is used to diagnose faults based on predicted theoretical temperature rise data and actual temperature rise data.

8. An electronic device, characterized in that, include: The processor, communication interface, memory, and communication bus are connected, with the processor, communication interface, and memory communicating with each other via the communication bus. The memory stores a computer program that, when executed by a processor, causes the processor to perform the steps of the power battery precharge fault diagnosis method as described in any one of claims 1 to 6.

9. A computer-readable storage medium, characterized in that, The device stores a computer program executable by an electronic device, which, when run on the electronic device, causes the electronic device to perform the steps of the power battery precharge fault diagnosis method as described in any one of claims 1 to 6.

10. A diagnostic prediction platform, characterized in that, include: An electronic device for implementing the steps of the power battery precharge fault diagnosis method as described in any one of claims 1 to 6; A processor that runs a program, and when the program runs, it executes the steps of the power battery precharge fault diagnosis method as described in any one of claims 1 to 6 from data output by the electronic device. A storage medium for storing a program that, when running, performs the steps of the power battery precharge fault diagnosis method as described in any one of claims 1 to 6 on data output from an electronic device.

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