A BMS overcurrent fault detection method and device

Abstract

The present application provides a BMS overcurrent fault detection method and device, which relates to the field of battery health management. The method includes: in response to the detection operation of the overcurrent fault in the battery to be detected, obtaining the initial power of the battery to be detected; obtaining the fault duration corresponding to the battery to be detected, and calculating the first power reduction of the battery to be detected based on the initial power and the fault duration; obtaining the current fault current corresponding to the battery to be detected, and calculating the second power reduction of the battery to be detected based on the initial power and the current fault current; calculating the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; judging whether the overcurrent fault power reduction is less than or equal to the preset calibrated power; if the overcurrent fault power reduction is less than or equal to the preset calibrated power, confirming that the battery to be detected has an overcurrent fault. The present application solves the problem of misjudgment in BMS overcurrent fault detection in the prior art.

Description

Technical Field

[0001] The present application relates to the field of battery health management, and in particular to a BMS overcurrent fault detection method and device. Background Art

[0002] In application scenarios such as electric vehicles, reliable battery management system (BMS) fault diagnosis can ensure the normal driving and range of the vehicle, reduce breakdowns caused by battery failure, and improve user experience and satisfaction. BMS fault diagnosis is of great significance for ensuring battery safety, extending battery life, improving system reliability and ensuring user experience.

[0003] The current mainstream BMS overcurrent fault will be divided into three levels based on the degree of overcurrent, and the corresponding fault processing will be carried out according to the severity of each level of overcurrent fault. Although this method can effectively perform overcurrent protection in many cases, due to the fixed overcurrent fault threshold and fault power reduction processing for different fault levels, and the accuracy error caused by the current sampling zero drift, especially when the overcurrent is on the verge of triggering the threshold but has not reached the threshold, the current fluctuation may be misjudged as the normal range, resulting in misjudgment of BMS overcurrent fault detection.

[0004] Therefore, there is an urgent need for a BMS overcurrent fault detection method and device. Summary of the invention

[0005] The present application provides a BMS overcurrent fault detection method and device, which solves the problem that the overcurrent fault threshold and fault power reduction processing are fixed for different fault levels, and there is an accuracy error caused by current sampling zero drift, especially when the overcurrent is on the verge of triggering the threshold but has not reached the threshold, the current fluctuation may be misjudged as a normal range, thereby causing misjudgment of BMS overcurrent fault detection.

[0006] In a first aspect of the present application, a BMS overcurrent fault detection method is provided, the method comprising: in response to a detection operation for an overcurrent fault in a battery to be detected, obtaining the initial power of the battery to be detected; obtaining the fault duration corresponding to the battery to be detected, and calculating the first power reduction of the battery to be detected based on the initial power and the fault duration; obtaining the current fault current corresponding to the battery to be detected, and calculating the second power reduction of the battery to be detected based on the initial power and the current fault current; calculating the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; judging whether the overcurrent fault power reduction is less than or equal to a preset calibrated power; if the overcurrent fault power reduction is less than or equal to the preset calibrated power, confirming that an overcurrent fault occurs in the battery to be detected.

[0007] Optionally, obtaining the fault duration corresponding to the battery to be detected specifically includes: obtaining a first moment and a second moment, the first moment being the corresponding moment when it is confirmed that the battery to be detected is in a high-voltage operating state, and the second moment being the current moment; obtaining the time period between the first moment and the second moment, and determining whether the time period is greater than the initial fault diagnosis time period; if the time period is greater than the initial fault diagnosis time period, taking the time period as the fault duration.

[0008] Optionally, calculating the first power drop of the battery to be detected based on the initial power and the fault duration specifically includes: calculating the first power drop according to the following formula:

[0009] P t =P0*[1-k1(T-T0)];

[0010] Among them, P t is the first power reduction, P0 is the initial power, T is the fault duration, T0 is the initial fault diagnosis time period, k1 is the first proportional coefficient, and the first proportional coefficient is used to quantify the impact of the fault duration on the first power reduction.

[0011] Optionally, the current fault current corresponding to the battery to be tested is obtained, specifically including: obtaining the initial fault judgment current, which is the maximum current of the charge and discharge pulses in the battery cell parameter table; obtaining the target current corresponding to the current moment, and judging whether the target current is greater than the initial fault judgment current; if the target current is greater than the initial fault judgment current, the target current is used as the current fault current.

[0012] Optionally, based on the first reduced power and the second reduced power, calculating the overcurrent fault reduced power corresponding to the battery to be detected specifically includes: calculating the overcurrent fault reduced power according to the following formula:

[0013] P=P0*[1-k1(T-T0)][1-k2(I-I0)];

[0014] Wherein, P is the overcurrent fault power reduction, I is the current fault current, I0 is the initial fault judgment current, k2 is the second proportional coefficient, and the second proportional coefficient is used to quantify the influence of the current fault current on the second power reduction.

[0015] Optionally, if the overcurrent fault power reduction is less than or equal to the preset calibrated power and it is confirmed that the battery to be detected has an overcurrent fault, the method also includes: constructing a fault duration influence function based on the fault duration, and the fault duration influence function is used to quantify the influence of the fault duration on the overcurrent fault; constructing a fault current influence function based on the current fault current, and the fault current influence function is used to quantify the influence of the current fault current on the overcurrent fault; calculating the lower high-voltage target voltage according to the fault duration influence function and the fault current influence function, and dynamically adjusting the voltage of the battery to be detected according to the lower high-voltage target voltage.

[0016] Optionally, calculating the lower high voltage target voltage according to the fault duration influence function and the fault current influence function specifically includes: calculating the lower high voltage target voltage according to the following formula:

[0017]

[0018] Among them, V d is the lower high voltage target voltage, V0 is the initial battery voltage of the battery to be detected, N is the number of segments, and the number of segments is used to adjust the influence of overcurrent fault power reduction on the voltage of the battery to be detected in segments, β n is the power influence coefficient corresponding to each segment, one segment corresponds to one power influence coefficient, α n is the nonlinear power influence index, which is used to control the nonlinear weighted effect of different power intervals on the voltage drop in the battery to be detected, f(T) is the fault duration influence function, and g(I) is the fault current influence function.

[0019] In a second aspect of the present application, a BMS overcurrent fault detection device is provided, the device comprising an acquisition module and a processing module, wherein:

[0020] An acquisition module is used to acquire the initial power of the battery to be detected in response to a detection operation for an overcurrent fault in the battery to be detected; acquire the fault duration corresponding to the battery to be detected, and calculate the first power drop of the battery to be detected based on the initial power and the fault duration; acquire the current fault current corresponding to the battery to be detected, and calculate the second power drop of the battery to be detected based on the initial power and the current fault current.

[0021] The processing module is used to calculate the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; determine whether the overcurrent fault power reduction is less than or equal to the preset calibrated power; if the overcurrent fault power reduction is less than or equal to the preset calibrated power, confirm that the battery to be detected has an overcurrent fault.

[0022] In the third aspect of the present application, an electronic device is provided, including a processor, a memory, a user interface and a network interface, the memory is used to store instructions, the user interface and the network interface are used to communicate with other devices, and the processor is used to execute the instructions stored in the memory so that the electronic device executes any one of the methods described above.

[0023] In a fourth aspect of the present application, a computer-readable storage medium is provided, wherein the computer-readable storage medium stores a computer program, and the computer program is executed by a processor to perform any of the above methods.

[0024] One or more technical solutions provided in the embodiments of the present application have at least the following technical effects or advantages:

[0025] 1. When performing the detection operation for an overcurrent fault in a battery to be detected, the initial power of the battery to be detected is obtained, the fault duration corresponding to the battery to be detected is obtained, and based on the initial power and the fault duration, the first power reduction of the battery to be detected is calculated, the current fault current corresponding to the battery to be detected is obtained, and based on the initial power and the current fault current, the second power reduction of the battery to be detected is calculated, thereby calculating the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction, and when it is determined that the overcurrent fault power reduction is less than or equal to the preset calibrated power, it is confirmed that the battery to be detected has an overcurrent fault, thereby not only simplifying the grading process of the overcurrent fault degree, but also detecting the overcurrent fault comprehensively through the fault duration and the current fault current, thereby greatly improving the accuracy of overcurrent fault judgment and reducing the probability of misjudgment of overcurrent faults.

[0026] 2. By obtaining the first moment and the second moment, the first moment is the corresponding moment when it is confirmed that the battery to be tested is in a high-voltage operating state, and the second moment is the current moment, and judging whether the time period between the first moment and the second moment is greater than the initial fault diagnosis time period, and only when the time period is greater than the initial fault diagnosis time period, it is taken as the fault duration, thereby effectively avoiding misjudgment due to short-term current fluctuations or instantaneous abnormalities.

[0027] 3. Based on the fault duration, a fault duration influence function is constructed, and based on the current fault current, a fault current influence function is constructed, so as to calculate the lower high-voltage target voltage according to the fault duration influence function and the fault current influence function, and dynamically adjust the voltage of the battery to be tested according to the lower high-voltage target voltage, and then through a multi-variable coupled nonlinear voltage adjustment method combined with a gradual voltage reduction strategy, flexible voltage control is provided at different fault development stages to protect battery stability and minimize power loss. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1It is a flow chart of a BMS overcurrent fault detection method provided in an embodiment of the present application;

[0029] Figure 2 It is a module schematic diagram of a BMS overcurrent fault detection device provided in an embodiment of the present application;

[0030] Figure 3 It is a structural schematic diagram of an electronic device provided in an embodiment of the present application.

[0031] Explanation of the reference numerals: 21, acquisition module; 22, processing module; 301, processor; 302, communication bus; 303, user interface; 304, network interface; 305, memory. DETAILED DESCRIPTION

[0032] In order to enable technicians in this field to better understand the technical solutions in this specification, the technical solutions in the embodiments of this specification will be clearly and completely described below in conjunction with the drawings in the embodiments of this specification. Obviously, the described embodiments are only part of the embodiments of this application, not all of the embodiments.

[0033] The terms used in the following embodiments of the present application are only for the purpose of describing specific embodiments, and are not intended to be used as limitations to the present application. As used in the specification of the present application, the singular expressions "one", "a kind of", "said", "above", "the" and "this" are intended to also include plural expressions, unless there is a clear indication to the contrary in the context. It should also be understood that the term "and / or" used in the present application refers to and includes any or all possible combinations of one or more listed items.

[0034] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features, and in the description of the embodiments of the present application, unless otherwise specified, "plurality" means two or more.

[0035] In order to enable those skilled in the art to better understand the technical solution of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] Please refer to Figure 1 , which shows a flow chart of a BMS overcurrent fault detection method provided in an embodiment of the present application. The method is applied to a battery management system. The flow chart mainly includes the following steps: S101 to S106.

[0037] Step S101 , in response to a detection operation for an overcurrent fault in a battery to be detected, obtaining an initial power of the battery to be detected.

[0038] Specifically, in application scenarios such as electric vehicles, reliable battery management system (BMS) fault diagnosis can ensure the normal driving and cruising range of the vehicle, reduce the breakdown caused by battery failure, and improve the user experience and satisfaction. BMS fault diagnosis is of great significance for ensuring battery safety, extending battery life, improving system reliability and ensuring user experience. In an embodiment of the present application, the initial power of the battery to be detected is obtained through BMS to detect the overcurrent fault in the battery to be detected. The initial power refers to the normal power that the battery to be detected can output when there is no overcurrent fault or other abnormal state in the battery to be detected, which can be obtained by real-time monitoring of the voltage and current of the battery.

[0039] Step S102, obtaining the fault duration corresponding to the battery to be detected, and calculating the first reduced power of the battery to be detected based on the initial power and the fault duration.

[0040] Specifically, during the detection operation of the overcurrent fault in the battery to be detected, the BMS needs to determine whether the battery to be detected has an overcurrent fault based on multiple battery operating parameters to improve the accuracy of the overcurrent fault judgment. Among them, the first battery operating parameter is the first power reduction. The BMS obtains the fault duration corresponding to the battery to be detected, and based on the initial power and the fault duration, calculates the first power reduction of the battery to be detected, and uses the first power reduction as a judgment parameter for subsequent overcurrent faults.

[0041] In a possible implementation, step S102 also includes: obtaining a first moment and a second moment, the first moment being the corresponding moment when it is confirmed that the battery to be detected is in a high-voltage operating state, and the second moment being the current moment; obtaining a time period between the first moment and the second moment, and determining whether the time period is greater than an initial fault diagnosis time period; if the time period is greater than the initial fault diagnosis time period, taking the time period as the fault duration.

[0042] Specifically, before the BMS detects the overcurrent fault in the battery to be detected, it needs to monitor in real time whether the battery to be detected is in a high-voltage operating state, and record the moment when the battery to be detected is in a high-voltage operating state as the first moment. After that, if the battery to be detected continues to be in a high-voltage operating state until the current moment, the current moment is recorded as the second moment, and the time period between the first moment and the second moment is the fault time period of the battery to be detected. The initial fault diagnosis time period is obtained. The initial fault time period is a time period set manually, which can be set according to experience. It is usually 5s, 7s, 9s, etc. This application does not limit the setting of the initial fault time period. And judge whether the fault time period of the battery to be detected is greater than the initial fault time period, and when the fault time period is greater than the initial fault time period, the fault time period is used as the fault duration corresponding to the battery to be detected. At this time, the battery to be detected has the risk of overcurrent fault, and the next step of judgment is required; when the fault time period is less than the initial fault time period, the battery to be detected does not have the risk of overcurrent fault, and continues to monitor in real time whether the battery to be detected is in a high-voltage operating state.

[0043] After confirming and obtaining the fault duration corresponding to the battery to be detected, the first power drop of the battery to be detected is calculated based on the initial power and the fault duration. The calculation method is as follows:

[0044] P t =P0*[1-k1(T-T0)];

[0045] Among them, P t is the first power reduction, P0 is the initial power, T is the fault duration, T0 is the initial fault diagnosis time period, k1 is the first proportional coefficient, and the first proportional coefficient is used to quantify the impact of the fault duration on the first power reduction.

[0046] Step S103, obtaining the current fault current corresponding to the battery to be detected, and calculating the second reduced power of the battery to be detected based on the initial power and the current fault current.

[0047] Specifically, during the detection operation of the overcurrent fault in the battery to be detected, the BMS needs to determine whether the battery to be detected has an overcurrent fault based on multiple battery operating parameters to improve the accuracy of the overcurrent fault judgment. Among them, the second battery operating parameter is the second reduced power. The BMS obtains the current fault current corresponding to the battery to be detected, and calculates the second reduced power of the battery to be detected based on the initial power and the current fault current, and uses the second reduced power as a judgment parameter for subsequent overcurrent faults.

[0048] In a possible implementation, step S103 also includes: obtaining an initial fault judgment current, which is the maximum current of the charge and discharge pulses in the battery cell parameter table; obtaining a target current corresponding to the current moment, and determining whether the target current is greater than the initial fault judgment current; if the target current is greater than the initial fault judgment current, using the target current as the current fault current.

[0049] Specifically, when the BMS detects an overcurrent fault in the battery to be detected, it will monitor the target current corresponding to the battery to be detected at the current moment in real time. The BMS obtains the initial fault judgment current, which is the maximum current of the charge and discharge pulses in the battery cell parameter table. It also determines whether the target current is greater than the initial fault judgment current, and when the target current is greater than the initial fault judgment current, the target current is used as the current fault current corresponding to the battery to be detected. At this time, the battery to be detected is at risk of overcurrent fault, and the next step of judgment is required; when the target current is less than the initial fault judgment current, the battery to be detected is not at risk of overcurrent fault, and the current fault current of the battery to be detected continues to be monitored in real time.

[0050] After confirming that the battery to be detected has the risk of overcurrent fault and obtaining the current fault current, the second drop power of the battery to be detected is calculated based on the initial power and the current fault current. The calculation method is as follows:

[0051] P I =P0*[1-k2(I-I0)];

[0052] Among them, P I is the second reduced power, I is the current fault current, I0 is the initial fault judgment current, k2 is the second proportional coefficient, and the second proportional coefficient is used to quantify the influence of the current fault current on the second reduced power.

[0053] Step S104: Calculate the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction.

[0054] Specifically, based on the product of the first power reduction and the second power reduction, the overcurrent fault power reduction is finally obtained, and the calculation method is as follows:

[0055] P=P0*[1-k1(T-T0)][1-k2(I-I0)].

[0056] Where P is the power reduction due to overcurrent fault, P tis the first power reduction, P0 is the initial power, T is the fault duration, T0 is the initial fault diagnosis time period, k1 is the first proportional coefficient, and the first proportional coefficient is used to quantify the influence of the fault duration on the first power reduction, I is the current fault current, I0 is the initial fault judgment current, k2 is the second proportional coefficient, and the second proportional coefficient is used to quantify the influence of the current fault current on the second power reduction.

[0057] Step S105, determining whether the overcurrent fault power reduction is less than or equal to the preset rated power.

[0058] Specifically, the BMS compares the overcurrent fault power reduction with the preset rated power to finally confirm whether there is an overcurrent fault in the battery to be tested. The preset rated power is a pre-determined safety standard, usually obtained through multiple experiments or historical data analysis. This value represents the maximum power change that the battery can withstand during normal operation, and can generally be set to 7.5KW.

[0059] Step S106: If the overcurrent fault power reduction is less than or equal to the preset calibrated power, it is confirmed that the battery to be detected has an overcurrent fault.

[0060] Specifically, after comparing the power reduction for overcurrent fault with the preset rated power, the BMS will determine whether to confirm that the battery to be tested has an overcurrent fault. For example, if the calculated power reduction for overcurrent fault is less than or equal to the preset rated power (such as 7.5kW), it is confirmed that the battery has an overcurrent fault. This process is not only a key step in fault diagnosis, but also a core link for the battery management system (BMS) to ensure safe operation of the battery.

[0061] For example, suppose there is an electric car whose battery pack has an overcurrent fault at a certain moment. The initial voltage of the battery is 400V and the initial power is 50kW. The BMS needs to detect and confirm the overcurrent fault, and then perform dynamic voltage adjustment to protect the battery. The BMS first detects that the battery to be detected (assuming it is the main battery pack of the vehicle) has an overcurrent fault. Initial power (P0): The initial power of the battery is recorded as 50kW. Initial voltage (V0): The initial voltage of the battery pack is 400V. According to the previous calculation method, the overcurrent fault power reduction P is calculated based on the fault duration T and the current fault current I. Assume that the fault duration is 2 seconds, the current fault current is 120A, and the overcurrent fault power reduction calculated by the BMS is 7kW. By comparison, the overcurrent fault power reduction is less than or equal to the preset rated power, that is, 7kW<7.5KW, so it can be confirmed that the battery has an overcurrent fault.

[0062] In a possible implementation, step S106 also includes: constructing a fault duration influence function based on the fault duration, the fault duration influence function is used to quantify the influence of the fault duration on the overcurrent fault; constructing a fault current influence function based on the current fault current, the fault current influence function is used to quantify the influence of the current fault current on the overcurrent fault; calculating the lower high voltage target voltage according to the fault duration influence function and the fault current influence function, and dynamically adjusting the voltage of the battery to be detected according to the lower high voltage target voltage.

[0063] Specifically, after the BMS confirms that an overcurrent fault occurs in the battery to be detected, the BMS can dynamically adjust the voltage of the battery to be detected by changing the battery operating parameters. The process of dynamic voltage adjustment is as follows: Based on the fault duration, a fault duration influence function is constructed. The fault duration influence function is used to quantify the influence of the fault duration on the overcurrent fault. The expression of the fault duration influence function is as follows:

[0064]

[0065] Among them, f(T) is the fault duration influence function, β1 is the time influence coefficient, which is used to control the rapid response of the fault duration to the voltage drop, γ1 is the sinusoidal adjustment amplitude, ω1 is the sinusoidal adjustment frequency, and γ1 and ω1 are used to simulate the voltage fluctuation trend under long-term faults. Based on the current fault current, a fault current influence function is constructed. The fault current influence function is used to quantify the influence of the current fault current on the overcurrent fault. The expression of the fault current influence function is as follows:

[0066]

[0067] Among them, g(I) is the fault current influence function, β2 is the current response coefficient, which controls the sensitivity of the fault current to the voltage reduction, γ2 is the cosine adjustment amplitude, ω2 is the cosine adjustment frequency, and γ2 and ω2 are used to increase the adaptability of voltage adjustment when the fault current fluctuates. Finally, the lower high voltage target voltage is calculated according to the fault duration influence function and the fault current influence function, and the voltage of the battery to be tested is dynamically adjusted according to the lower high voltage target voltage, and the lower high voltage target voltage is calculated according to the following formula:

[0068]

[0069] Among them, V d is the lower high voltage target voltage, V0 is the initial battery voltage of the battery to be detected, N is the number of segments, and the number of segments is used to adjust the influence of overcurrent fault power reduction on the voltage of the battery to be detected in segments, β n is the power influence coefficient corresponding to each segment, one segment corresponds to one power influence coefficient, α nis the nonlinear power influence index, which is used to control the nonlinear weighted effect of different power intervals on the voltage drop in the battery to be detected, f(T) is the fault duration influence function, and g(I) is the fault current influence function.

[0070] In the above formula, each time the high-voltage target voltage is calculated, the final value of the high-voltage target voltage is adjusted according to the real-time change values ​​of the fault duration influence function and the fault current influence function, and the voltage is gradually reduced to the final safe voltage value. In each stage, the dynamic voltage adjustment will re-evaluate the battery status according to the latest overcurrent fault power reduction, fault duration and fault current to decide whether to continue to reduce the voltage or maintain the current voltage. Through the nonlinear voltage adjustment method of multi-variable coupling, combined with the gradual voltage reduction strategy, flexible voltage control is provided at different fault development stages to protect battery stability and minimize power loss.

[0071] The present application adopts the above method. When performing the detection operation for an overcurrent fault in a battery to be detected, the initial power of the battery to be detected is obtained, the fault duration corresponding to the battery to be detected is obtained, and based on the initial power and the fault duration, the first reduced power of the battery to be detected is calculated, the current fault current corresponding to the battery to be detected is obtained, and based on the initial power and the current fault current, the second reduced power of the battery to be detected is calculated, thereby calculating the overcurrent fault reduced power corresponding to the battery to be detected based on the first reduced power and the second reduced power, and when it is determined that the overcurrent fault reduced power is less than or equal to the preset calibrated power, it is confirmed that an overcurrent fault has occurred in the battery to be detected, thereby not only simplifying the grading process of the overcurrent fault degree, but also detecting the overcurrent fault comprehensively through the fault duration and the current fault current, thereby greatly improving the accuracy of overcurrent fault judgment and reducing the probability of misjudgment of overcurrent faults.

[0072] Please refer to Figure 2 , which shows a module schematic diagram of a BMS overcurrent fault detection device provided in an embodiment of the present application, the device includes an acquisition module 21 and a processing module 22, wherein:

[0073] The acquisition module 21 is used to obtain the initial power of the battery to be detected in response to the detection operation of the overcurrent fault in the battery to be detected; obtain the fault duration corresponding to the battery to be detected, and calculate the first power drop of the battery to be detected based on the initial power and the fault duration; obtain the current fault current corresponding to the battery to be detected, and calculate the second power drop of the battery to be detected based on the initial power and the current fault current.

[0074] The processing module 22 is used to calculate the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; determine whether the overcurrent fault power reduction is less than or equal to the preset calibrated power; if the overcurrent fault power reduction is less than or equal to the preset calibrated power, confirm that the battery to be detected has an overcurrent fault.

[0075] In a possible implementation, the acquisition module 21 is used to obtain the fault duration corresponding to the battery to be detected, specifically including: obtaining a first moment and a second moment, the first moment being the corresponding moment when it is confirmed that the battery to be detected is in a high-voltage operating state, and the second moment being the current moment; obtaining the time period between the first moment and the second moment, and determining whether the time period is greater than the initial fault diagnosis time period; if the time period is greater than the initial fault diagnosis time period, the time period is used as the fault duration.

[0076] In a possible implementation manner, the acquisition module 21 is used to calculate the first power reduction of the battery to be detected based on the initial power and the fault duration, specifically including: calculating the first power reduction according to the following formula:

[0077] P t =P0*[1-k1(T-T0)];

[0078] Among them, P t is the first power reduction, P0 is the initial power, T is the fault duration, T0 is the initial fault diagnosis time period, k1 is the first proportional coefficient, and the first proportional coefficient is used to quantify the impact of the fault duration on the first power reduction.

[0079] In one possible implementation, the acquisition module 21 is used to obtain the current fault current corresponding to the battery to be detected, specifically including: obtaining the initial fault judgment current, which is the maximum current of the charge and discharge pulses in the battery cell parameter table; obtaining the target current corresponding to the current moment, and judging whether the target current is greater than the initial fault judgment current; if the target current is greater than the initial fault judgment current, the target current is used as the current fault current.

[0080] In a possible implementation manner, the processing module 22 is used to calculate the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction, specifically including: calculating the overcurrent fault power reduction according to the following formula:

[0081] P=P0*[1-k1(T-T0)][1-k2(I-I0)];

[0082] Wherein, P is the overcurrent fault power reduction, I is the current fault current, I0 is the initial fault judgment current, k2 is the second proportional coefficient, and the second proportional coefficient is used to quantify the influence of the current fault current on the second power reduction.

[0083] In one possible implementation, the processing module 22 is used to confirm that an overcurrent fault has occurred in the battery to be detected if the power reduction due to the overcurrent fault is less than or equal to the preset calibrated power. The method also includes: constructing a fault duration influence function based on the fault duration, and the fault duration influence function is used to quantify the influence of the fault duration on the overcurrent fault; constructing a fault current influence function based on the current fault current, and the fault current influence function is used to quantify the influence of the current fault current on the overcurrent fault; calculating the lower high-voltage target voltage according to the fault duration influence function and the fault current influence function, and dynamically adjusting the voltage of the battery to be detected according to the lower high-voltage target voltage.

[0084] In a possible implementation manner, the processing module 22 is used to calculate the lower high voltage target voltage according to the fault duration influence function and the fault current influence function, specifically including: calculating the lower high voltage target voltage according to the following formula:

[0085]

[0086] Among them, V d is the lower high voltage target voltage, V0 is the initial battery voltage of the battery to be detected, N is the number of segments, and the number of segments is used to adjust the influence of overcurrent fault power reduction on the voltage of the battery to be detected in segments, β n is the power influence coefficient corresponding to each segment, one segment corresponds to one power influence coefficient, α n is the nonlinear power influence index, which is used to control the nonlinear weighted effect of different power intervals on the voltage drop in the battery to be detected, f(T) is the fault duration influence function, and g(I) is the fault current influence function.

[0087] It should be noted that: when the device provided in the above embodiment realizes its function, only the division of the above functional modules is used as an example. In actual application, the above functions can be assigned to different functional modules as needed, that is, the internal structure of the device is divided into different functional modules to complete all or part of the functions described above. In addition, the device and method embodiments provided in the above embodiment belong to the same concept, and the specific implementation process is detailed in the method embodiment, which will not be repeated here.

[0088] The present application also provides an electronic device. Figure 3 , Figure 3 30 is a schematic diagram of the structure of an electronic device provided in an embodiment of the present application. The electronic device may include: at least one processor 301, at least one communication bus 302, a user interface 303, at least one network interface 304, and a memory 305.

[0089] The communication bus 302 is used to realize the connection and communication between these components.

[0090] The user interface 303 may include a display screen (Display) and a camera (Camera). The optional user interface 303 may also include a standard wired interface and a wireless interface.

[0091] The network interface 304 may optionally include a standard wired interface or a wireless interface (such as a WI-FI interface).

[0092] Among them, the processor 301 may include one or more processing cores. The processor 301 uses various interfaces and lines to connect various parts in the entire server, and executes various functions of the server and processes data by running or executing instructions, programs, code sets or instruction sets stored in the memory 305, and calling data stored in the memory 305. Optionally, the processor 301 can be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field programmable gate array (Field-Programmable Gate Array, FPGA), and programmable logic array (Programmable Logic Array, PLA). The processor 301 can integrate one or a combination of a central processing unit (Central Processing Unit, CPU), a graphics processing unit (Graphics Processing Unit, GPU) and a modem. Among them, the CPU mainly processes the operating system, user interface and application programs; the GPU is responsible for rendering and drawing the content to be displayed on the display screen; the modem is used to process wireless communications. It can be understood that the above-mentioned modem may not be integrated into the processor 301, and it can be implemented separately through a chip.

[0093] Among them, the memory 305 may include a random access memory (Random Access Memory, RAM) and may also include a read-only memory (Read-Only Memory). Optionally, the memory 305 includes a non-transitory computer-readable storage medium. The memory 305 can be used to store instructions, programs, codes, code sets or instruction sets. The memory 305 may include a program storage area and a data storage area, wherein the program storage area may store instructions for implementing an operating system, instructions for at least one function (such as a touch function, a sound playback function, an image playback function, etc.), instructions for implementing the above-mentioned various method embodiments, etc.; the data storage area may store data involved in the above-mentioned various method embodiments, etc. The memory 305 may optionally also be at least one storage device located away from the aforementioned processor 301. Refer to Figure 3 , the memory 305 as a computer storage medium may include an operating system, a network communication module, a user interface module, and a BMS overcurrent fault detection application.

[0094] exist Figure 3 In the electronic device shown, the user interface 303 is mainly used to provide an input interface for the user and obtain the data input by the user; and the processor 301 can be used to call the BMS overcurrent fault detection application stored in the memory 305. When executed by one or more processors 301, the electronic device executes one or more of the methods described in the above embodiments. It should be noted that for the aforementioned method embodiments, for the sake of simple description, they are all expressed as a series of action combinations, but those skilled in the art should be aware that the present application is not limited to the described order of actions, because according to the present application, certain steps can be performed in other orders or simultaneously. Secondly, those skilled in the art should also be aware that the embodiments described in the specification are all preferred embodiments, and the actions and modules involved are not necessarily required for the present application.

[0095] The present application also provides a computer-readable storage medium, which stores instructions. When executed by one or more processors, the electronic device executes one or more of the methods described in the above embodiments.

[0096] In the above embodiments, the description of each embodiment has its own emphasis. For parts that are not described in detail in a certain embodiment, reference can be made to the relevant descriptions of other embodiments.

[0097] In the several embodiments provided in this application, it should be understood that the disclosed devices can be implemented in other ways. For example, the device embodiments described above are only schematic, such as the division of units, which is only a logical function division. There may be other division methods in actual implementation, such as multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some service interfaces, and the indirect coupling or communication connection of devices or units can be electrical or other forms.

[0098] The units described as separate components may or may not be physically separated, and the components shown as units may or may not be physical units, that is, they may be located in one place or distributed on multiple network units. Some or all of the units may be selected according to actual needs to achieve the purpose of the solution of this embodiment.

[0099] In addition, each functional unit in each embodiment of the present application may be integrated into one processing unit, or each unit may exist physically separately, or two or more units may be integrated into one unit. The above-mentioned integrated unit may be implemented in the form of hardware or in the form of software functional units.

[0100] If the integrated unit is implemented in the form of a software functional unit and sold or used as an independent product, it can be stored in a computer-readable memory. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art, or all or part of the technical solution can be embodied in the form of a software product, which is stored in a memory and includes several instructions for a computer device (which can be a personal computer, server or network device, etc.) to perform all or part of the steps of the various embodiments of the present application. The aforementioned memory includes: various media that can store program codes, such as USB flash drives, mobile hard drives, magnetic disks or optical disks.

[0101] The above are only exemplary embodiments disclosed in this application, and the scope of the disclosure of this application cannot be limited by this. That is, any equivalent changes and modifications made according to the teachings disclosed in this application are still within the scope of the disclosure of this application. After considering the disclosure of the specification and the truth of practice, those skilled in the art will easily think of other implementation schemes disclosed in this application.

[0102] This application is intended to cover any modifications, uses or adaptive changes disclosed in this application, which follow the general principles disclosed in this application and include common knowledge or customary technical means in the technical field not recorded in this application.

Claims

1. A BMS overcurrent fault detection method, characterized in that: The method comprises: In response to a detection operation for an overcurrent fault in a battery to be detected, obtaining an initial power of the battery to be detected; Acquire the fault duration corresponding to the battery to be detected, and calculate the first reduced power of the battery to be detected based on the initial power and the fault duration; Acquire a current fault current corresponding to the battery to be detected, and calculate a second reduced power of the battery to be detected based on the initial power and the current fault current; Calculating an overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; Determine whether the overcurrent fault power reduction is less than or equal to a preset rated power; If the overcurrent fault power reduction is less than or equal to the preset calibrated power, it is confirmed that the overcurrent fault occurs in the battery to be detected.

2. The method according to claim 1, characterized in that The obtaining of the fault duration corresponding to the battery to be detected specifically includes: Acquire a first moment and a second moment, wherein the first moment is a corresponding moment when it is confirmed that the battery to be detected is in a high-voltage operating state, and the second moment is the current moment; Obtaining a time period between the first moment and the second moment, and determining whether the time period is greater than an initial fault diagnosis time period; If the time period is greater than the initial fault diagnosis time period, the time period is used as the fault duration time.

3. The method according to claim 2, characterized in that The calculating, based on the initial power and the fault duration, a first reduced power of the battery to be detected specifically includes: The first reduction power is calculated according to the following formula: P t =P0*[1-k1(T-T0)]; Among them, P t is the first power reduction, P0 is the initial power, T is the fault duration, T0 is the initial fault diagnosis time period, k1 is a first proportional coefficient, and the first proportional coefficient is used to quantify the impact of the fault duration on the first power reduction.

4. The method according to claim 3, characterized in that The obtaining of the current fault current corresponding to the battery to be detected specifically includes: Obtaining an initial fault judgment current, wherein the initial fault judgment current is a maximum current of a charge and discharge pulse in a battery cell parameter table; Obtaining a target current corresponding to the current moment, and determining whether the target current is greater than the initial fault determination current; If the target current is greater than the initial fault judgment current, the target current is used as the current fault current.

5. The method according to claim 4, characterized in that The calculating, based on the first power reduction and the second power reduction, the overcurrent fault power reduction corresponding to the battery to be detected specifically includes: The overcurrent fault power reduction is calculated according to the following formula: P=P0*[1-k1(T-T0)][1-k2(I-I0)]; Among them, P is the overcurrent fault power reduction, I is the current fault current, I0 is the initial fault judgment current, k2 is the second proportional coefficient, and the second proportional coefficient is used to quantify the impact of the current fault current on the second power reduction.

6. The method according to claim 1, characterized in that If the overcurrent fault power reduction is less than or equal to the preset rated power, after confirming that the overcurrent fault occurs in the battery to be detected, the method further includes: Based on the fault duration, construct a fault duration influence function, wherein the fault duration influence function is used to quantify the influence of the fault duration on the overcurrent fault; Based on the current fault current, construct a fault current influence function, wherein the fault current influence function is used to quantify the influence degree of the current fault current on the overcurrent fault; A lower high voltage target voltage is calculated according to the fault duration influence function and the fault current influence function, and the voltage of the battery to be detected is dynamically adjusted according to the lower high voltage target voltage.

7. The method according to claim 6, characterized in that The calculating the lower high voltage target voltage according to the fault duration influence function and the fault current influence function specifically includes: The lower high voltage target voltage is calculated according to the following formula: Among them, V d is the lower high voltage target voltage, V0 is the initial battery voltage of the battery to be detected, N is the number of segments, and the number of segments is used to segmentally adjust the influence of the overcurrent fault power reduction on the voltage of the battery to be detected, β n is the power influence coefficient corresponding to each segment, one segment corresponds to one power influence coefficient, α n is a nonlinear power influence index, which is used to control the nonlinear weighted effect of different power intervals on the voltage drop in the battery to be detected, f(T) is the fault duration influence function, and g(I) is the fault current influence function.

8. A BMS overcurrent fault detection device, characterized in that: The device comprises an acquisition module and a processing module, wherein: The acquisition module is used to, in response to a detection operation for an overcurrent fault in a battery to be detected, acquire an initial power of the battery to be detected; acquire a fault duration corresponding to the battery to be detected, and calculate a first power drop of the battery to be detected based on the initial power and the fault duration; acquire a current fault current corresponding to the battery to be detected, and calculate a second power drop of the battery to be detected based on the initial power and the current fault current; The processing module is used to calculate the overcurrent fault power reduction corresponding to the battery to be detected based on the first power reduction and the second power reduction; determine whether the overcurrent fault power reduction is less than or equal to the preset calibrated power; if the overcurrent fault power reduction is less than or equal to the preset calibrated power, confirm that the overcurrent fault occurs in the battery to be detected.

9. An electronic device, characterized in that: It includes a processor, a communication bus, a user interface, a network interface and a memory, wherein the memory is used to store instructions, the user interface and the network interface are used to communicate with other devices, and the processor is used to execute the instructions stored in the memory so that the electronic device executes the method according to any one of claims 1 to 7.

10. A computer-readable storage medium, characterized in that: The computer-readable storage medium stores instructions, and when the instructions are executed, the method according to any one of claims 1 to 7 is performed.

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