Short-circuit fault monitoring and protecting method and system suitable for high-capacity battery pack

Abstract

The invention relates to a short-circuit fault monitoring and protection method and system suitable for a high-capacity battery pack, and the method comprises the following steps: constructing a battery short-circuit fault monitoring architecture which comprises a control cabinet, a battery cabinet, a battery management system, a fault diagnosis unit, a main control box, a battery box, and a battery monitoring unit; collecting the voltage and current of the battery box, the charge state and temperature change of the battery, and the voltage and current level of the whole battery cabinet; the fault diagnosis unit outputs a short-circuit fault diagnosis result through the collected information; first fuses are installed at positive and negative electrode buses of the battery pack, second fuses are installed at the positive electrode position of each battery box, and third fuses are installed at the positive and negative electrode positions of each battery cabinet; and according to the short-circuit fault diagnosis result and the fusing actions of the first fuse, the second fuse and the third fuse, determining different influences of the short-circuit fault on the batteries at different positions, and determining a corresponding short-circuit fault overhaul and maintenance scheme.

Description

Technical Field

[0001] The present application relates to the technical field of battery electrical protection, and more specifically, to a short-circuit fault monitoring and protection method and system suitable for large-capacity battery packs. Background Art

[0002] In order to promote the progress of the dual carbon goals, 100-megawatt-hour energy storage power stations have been widely put into operation in provinces such as Hunan and Jiangsu in China, making important contributions to the peak and frequency regulation of power grids in various regions, emergency support, and suppression of new energy fluctuations. The construction of gigawatt-hour energy storage power stations has also been vigorously developed as a strategic emerging industry, and energy storage systems are developing towards scale and modularization. However, in recent years, fires and explosions in energy storage power stations have occurred frequently, which has attracted great attention from the industry. For high-voltage battery integrated systems, the probability of accidents is higher, and accidents caused by internal short circuits in battery packs are more serious. Therefore, safety issues have become a key factor in the design and application of battery energy storage systems, and reasonable protection measures and operation and maintenance plans need to be taken when faults are quickly detected.

[0003] At present, the safety warning of energy storage system cannot realize early fault monitoring and timely isolation of faults, and the protection and maintenance scheme for short-circuit faults is not comprehensive enough. Patents for battery energy storage protection schemes often install current sensors and controllers on the positive and negative poles of the battery module. The first end of the current sensor is connected to the positive output end of the battery pack, and the second end of the current sensor is connected to the negative output end of the battery pack to detect the current difference between the positive output end and the negative output end of the battery pack. The controller is used to control the disconnection of the disconnecting device when the current difference detected by the current sensor is greater than the first threshold value, so as to quickly cut off the fault when a short circuit fault occurs to the ground in the battery cell in the battery pack, ensuring the safe operation of the entire energy storage system. However, most of the existing research is aimed at battery cells, and the use of short-circuiters to break the large current during faults. For large-capacity battery packs with thousands of battery cells, using battery cells as monitoring units will consume a lot of manpower and economic costs. Therefore, this patent proposes a short-circuit fault monitoring and protection scheme suitable for large-capacity battery packs, aiming to effectively protect the safety of energy storage systems while reducing investment costs.

[0004] Existing technologies such as the Chinese patent with patent number "CN117277516A" disclose a multi-level and multi-directional marine battery electrical protection system, including an active protection module, a passive protection module, and a manual protection module. The active protection module includes multiple protection modules, and the protection module includes a data acquisition unit, a data processing unit, an execution unit, an alarm unit, and a communication unit. The passive protection module includes a short-circuit protector and a thermal runaway protector, and the manual protection module includes a manually triggered emergency stop switch. The system of the invention adopts multiple protection modules and protection modules to provide multiple protection levels, cooperate with each other, and form a comprehensive protection mechanism; the system will automatically trigger protection measures, quickly cut off the fault circuit to avoid accidents, and can promptly issue sound and light alarms to remind the crew to pay attention; through the connection between the communication unit and the host computer, the crew can remotely monitor the status of the battery system, timely understand the system operation, and perform troubleshooting and maintenance management.

[0005] The problems with the above-mentioned prior art are that the system is complex and has high economic costs. The highly complex structure may increase the difficulty of designing, installing, debugging and maintaining the system, and professional technicians are required to operate it. There may also be coordination problems between modules, increasing the risk of system failure. The manual protection module of the system requires human intervention, but in an emergency, the personnel may not be able to operate the emergency stop switch in a timely and accurate manner due to nervousness, panic, etc., resulting in the system being unable to cut off the circuit in time and unable to effectively prevent the occurrence or expansion of accidents. Summary of the invention

[0006] In order to solve the above technical problems, the present invention proposes a short-circuit fault monitoring and protection method and system suitable for large-capacity battery packs.

[0007] The technical solution of the present invention is as follows:

[0008] The present invention provides a short circuit fault monitoring and protection method suitable for a large-capacity battery pack, comprising the following steps:

[0009] Step S1, constructing a battery short circuit fault monitoring architecture, including: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, a battery box, and a battery monitoring unit installed in the battery box;

[0010] Step S2, collecting the voltage, current, battery state of charge and temperature change of the battery box through the battery monitoring unit, collecting the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet; summarizing the information collected by the battery monitoring unit and the main control box through the battery management system in the control cabinet and outputting it to the fault diagnosis unit, and outputting the short circuit fault diagnosis result through the fault diagnosis unit;

[0011] Step S3, installing a first fuse at the positive and negative busbars of the battery pack, installing a second fuse at the positive position of each battery box, and installing a third fuse at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault;

[0012] Step S4, confirming the different effects of the short-circuit fault on batteries at different locations based on the short-circuit fault diagnosis result and the blowing actions of the first fuse, the second fuse, and the third fuse, and determining a corresponding short-circuit fault inspection and maintenance plan.

[0013] As a preferred embodiment, the first fuse is used to protect the power module of the battery pack: the melting threshold of the first fuse is set according to the current value flowing through the positive and negative busbars of the battery pack, and the specific calculation formula of the current value flowing through the positive and negative busbars of the battery pack is as follows:

[0014]

[0015] Among them, I mid is the intermediate calculation amount, and the expression is:

[0016]

[0017] In the formula, is the current value flowing through the positive and negative busbars of the battery pack, are the output power, voltage and current of battery pack a respectively, k is the number of short-circuited batteries, there are (nk) batteries outside the short-circuit point, where k<n, R f is the transition resistance of short circuit fault, I f is the short-circuit current, E is the electromotive force of the battery cell, m is the number of battery packs in parallel in the battery pack, n is the total number of batteries, R n is the internal resistance of a single battery.

[0018] As a preferred embodiment, the second fuse is used to cut off the short circuit between the battery box and the battery cabinet; the fusing threshold of the second fuse is set according to the current value flowing through the positive pole position of the battery box, and the specific calculation formula of the current value flowing through the positive pole position of the battery box is as follows:

[0019]

[0020] Where: is the current value at the positive pole of the battery box, I c is the internal current of the battery pack when k batteries in the battery pack are short-circuited.

[0021] As a preferred implementation, the third fuse is used to cut off the short-circuit current between battery cabinets; the third fuse is connected in series with the second fuse, and the melting threshold of the third fuse is the same as the melting threshold of the second fuse.

[0022] As a preferred implementation, the faulty battery is repaired or replaced according to the short-circuit fault repair and maintenance plan, wherein the fault repair and maintenance plan includes: primary repair, secondary repair and battery replacement. The specific fault repair and maintenance plan is as follows:

[0023] Level 1 overhaul: short circuit failure inside the battery box. The fault monitoring unit detects a large current in the faulty battery cabinet, and the first fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery failure in the non-faulty battery cabinet is marked as level 1 overhaul.

[0024] Level 2 overhaul: short circuit fault between battery boxes. The fault monitoring unit detects that the current of the faulty and non-faulty battery cabinets increases, but it is within the normal operating value, and the second fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery fault of the non-faulty battery cabinet is marked as level 2 overhaul.

[0025] Replace all of them. A short circuit fault occurred between the battery cabinets. The current of all battery cabinets has greatly exceeded the normal operating value. The third fuse has blown. All batteries in the faulty battery cabinet and the non-faulty battery cabinet need to be replaced.

[0026] On the other hand, the present invention also provides a short circuit fault monitoring and protection system suitable for a large-capacity battery pack, comprising:

[0027] A short-circuit fault detection architecture building module is used to build a battery short-circuit fault monitoring architecture, wherein the battery short-circuit fault monitoring architecture includes: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, and a battery monitoring unit installed in the battery box;

[0028] The battery information collection module collects the voltage, current, battery charge state and temperature change of the battery box through the battery monitoring unit installed in the battery box, collects the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet, and the battery management system in the control cabinet summarizes the information collected by the battery monitoring unit and the main control box and outputs the results through the fault diagnosis unit to guide fault handling;

[0029] A fuse arrangement module is provided, wherein a first fuse is installed at the positive and negative busbars of the battery pack, a second fuse is installed at the positive position of each battery box, and a third fuse is installed at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault;

[0030] The diagnosis and repair suggestion module confirms the different impacts of the short-circuit fault on batteries in different positions of the battery module based on the short-circuit fault diagnosis results output by the battery management system and the fusing actions of the first fuse, the second fuse, and the third fuse, and repairs or replaces the faulty batteries according to the short-circuit fault repair and maintenance plan.

[0031] As a preferred embodiment, the first fuse is used to protect the power module of the battery pack: the melting threshold of the first fuse is set according to the current value flowing through the positive and negative busbars of the battery pack, and the specific calculation formula of the current value is as follows:

[0032]

[0033] Among them, I mid is the intermediate calculation amount, and the expression is:

[0034]

[0035] In the formula, is the current value flowing through the positive and negative busbars of the battery pack, are the output power, voltage and current of battery pack a respectively, k is the number of short-circuited batteries, there are (nk) batteries outside the short-circuit point, where k<n, R f is the transition resistance of short circuit fault, I f is the short-circuit current, E is the electromotive force of the battery cell, m is the number of battery packs in parallel in the battery pack, n is the total number of batteries, R n is the internal resistance of a single battery.

[0036] As a preferred embodiment, the second fuse is used to cut off the short circuit between the battery box and the battery cabinet; the fusing threshold of the second fuse is set according to the current value flowing through the positive pole of the battery box, and the specific calculation formula of the current value is as follows:

[0037]

[0038] Where: is the current value at the positive pole of the battery box, I c is the internal current of the battery pack when k batteries in the battery pack are short-circuited.

[0039] On the other hand, the present invention further provides an electronic device having a computer program stored thereon, wherein when the computer program is executed by a processor, a short-circuit fault monitoring and protection method applicable to a large-capacity battery pack as described in any embodiment of the present invention is implemented.

[0040] On the other hand, the present invention also provides a computer-readable medium for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement a short-circuit fault monitoring and protection method suitable for a large-capacity battery pack as described in any embodiment of the present invention.

[0041] The present invention has the following beneficial effects:

[0042] 1. The monitoring and diagnostic unit is installed according to the actual structure of the battery pack, and the fuse is used to cut off the fault circuit, which is more economical while meeting the engineering application requirements. The fuse threshold and installation position are determined through theoretical calculation and simulation verification, which can not only effectively protect the safety of the power module, but also cut off the current in time under different short-circuit conditions to prevent the battery from being damaged by long-term high current.

[0043] 2. Based on the differences in the impact of different types of short-circuit faults on batteries in different positions of the battery module, a detailed graded operation and maintenance plan has been formulated to improve operation and maintenance efficiency and save costs. At the same time, the maintenance level can be adjusted according to the subsequent operation of the battery, which is more flexible. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required for use in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show certain embodiments of the present application and therefore should not be regarded as limiting the scope. For ordinary technicians in this field, other related drawings can be obtained based on these drawings without paying creative work.

[0045] Figure 1 This is a schematic diagram of the method flow of Example 1;

[0046] Figure 2 This is a schematic diagram of fuse installation;

[0047] Figure 3(a) is a diagram showing the terminal voltage variation output by the diagnostic model;

[0048] Figure 3(b) is a diagram showing the short-circuit current variation output by the diagnostic model;

[0049] Figure 4 This is a diagram of the battery pack short circuit fault monitoring architecture.

[0050] The reference numerals in the figure represent:

[0051] f d is the first fuse; f p is the second fuse; f n It is the third fuse. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0053] It should be understood that the step numbers used in this document are only for convenience of description and are not intended to limit the order in which the steps are executed.

[0054] It should be understood that the terms used in the present specification are only for the purpose of describing specific embodiments and are not intended to limit the present invention. As used in the present specification and the appended claims, unless the context clearly indicates otherwise, the singular forms "a", "an" and "the" are intended to include plural forms.

[0055] The terms “include” and “comprising” indicate the presence of described features, integers, steps, operations, elements and / or components, but do not exclude the presence or addition of one or more other features, integers, steps, operations, elements, components and / or combinations thereof.

[0056] The term "and / or" means and includes any and all possible combinations of one or more of the associated listed items.

[0057] Embodiment 1:

[0058] In order to make the purpose, technical solutions and advantages of the present invention more clear, the following will be combined with the specific embodiments of the present application and refer to the attached Figure 1 , clearly and completely describe the technical solution of the present invention.

[0059] In order to solve the problems in the prior art, the present invention provides a short circuit fault monitoring and protection method applicable to a large-capacity battery pack, comprising the following steps:

[0060] Step S1, constructing a battery short circuit fault monitoring architecture, including: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, a battery box, and a battery monitoring unit installed in the battery box;

[0061] In order to comprehensively and reliably monitor the battery pack status while reducing the battery cost, this embodiment installs the monitoring and diagnosis unit according to the actual battery pack structure. The specific monitoring architecture is shown in the attached Figure 4 It consists of 1 control cabinet and 25 battery cabinets, each of which contains 1 main control box and 5 battery monitoring units.

[0062] Step S2, collecting the voltage, current, battery state of charge and temperature change of the battery box through the battery monitoring unit, collecting the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet; summarizing the information collected by the battery monitoring unit and the main control box through the battery management system in the control cabinet and outputting it to the fault diagnosis unit, and outputting the short circuit fault diagnosis result through the fault diagnosis unit;

[0063] Each battery monitoring unit is installed in a battery box. The battery monitoring unit mainly collects the voltage, current, SOC and temperature changes of the battery box. The main control box is mainly composed of a battery management system, wiring harness, wiring terminals, etc., which are used to collect the voltage and current levels of each battery monitoring unit and the battery cabinet as a whole. The control cabinet contains a battery management system, which is responsible for collecting and summarizing the collected information of all battery cabinets. The battery management system summarizes and pre-processes the collected information and transmits it to the fault diagnosis unit. According to the internally implanted battery fault diagnosis method, it outputs the fault diagnosis results to guide the system to perform corresponding fault removal and maintenance measures.

[0064] Step S3, installing a first fuse at the positive and negative busbars of the battery pack, installing a second fuse at the positive position of each battery box, and installing a third fuse at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault;

[0065] The first fuse installation position is as follows Figure 2 As shown, the first fuse is used to protect the power module of the battery pack: the melting threshold of the first fuse is set according to the current value flowing through the positive and negative busbars of the battery pack. The specific calculation formula of the current value flowing through the positive and negative busbars of the battery pack is as follows:

[0066]

[0067] Among them, I mid is the intermediate calculation amount, and the expression is:

[0068]

[0069] In the formula, is the current value flowing through the positive and negative busbars of the battery pack, are the output power, voltage and current of battery pack a respectively, k is the number of short-circuited batteries, there are (nk) batteries outside the short-circuit point, where k<n, R f is the transition resistance of short circuit fault, I f is the short-circuit current, E is the electromotive force of the battery cell, m is the number of battery packs in parallel in the battery pack, n is the total number of batteries, R n is the internal resistance of a single battery.

[0070] The second fuse installation position is as follows Figure 2 As shown, it is used to cut off the short circuit between the battery box and the battery cabinet; the melting threshold of the second fuse is adjusted according to the current value flowing through the positive pole position of the battery box. The specific calculation formula of the current value flowing through the positive pole position of the battery box is as follows:

[0071]

[0072] Where: is the current value at the positive pole of the battery box, I c is the internal current of the battery pack when k batteries in the battery pack are short-circuited.

[0073] The third fuse installation position is as follows Figure 2 As shown, it is used to cut off the short-circuit current between battery cabinets; the third fuse is in series with the second fuse, and the melting threshold of the third fuse is the same as the melting threshold of the second fuse, that is,

[0074]

[0075] The working effect of the fuse is determined by the simulation model. The simulation results are shown in Figure 3, where the fault occurs at 1s and the fuse is activated at 1.2s. As shown in Figure 3(a), when the fuse is not installed, the fault voltage will continue to drop to about 855V. After the fuse is activated, the fault will be immediately cut off. After a transient change of about 0.1s, the system will return to the initial voltage state. As shown in Figure 3(b), when the fuse is not installed, the short-circuit current will continue to remain at about 46kA. After the fuse is activated, the fault can be cut off and the short-circuit current drops to 0, which can effectively suppress the development of the fault.

[0076] Step S4, confirming the different effects of the short-circuit fault on batteries at different locations based on the short-circuit fault diagnosis result and the blowing actions of the first fuse, the second fuse, and the third fuse, and determining a corresponding short-circuit fault inspection and maintenance plan.

[0077] The faulty battery is repaired or replaced according to the short-circuit fault repair and maintenance plan, wherein the fault repair and maintenance plan includes: primary repair, secondary repair and battery replacement. The specific fault repair and maintenance plan is as follows:

[0078] Level 1 overhaul: short circuit failure inside the battery box. The fault monitoring unit detects a large current in the faulty battery cabinet, and the first fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery failure in the non-faulty battery cabinet is marked as level 1 overhaul.

[0079] Level 2 overhaul: short circuit fault between battery boxes. The fault monitoring unit detects that the current of the faulty and non-faulty battery cabinets increases, but it is within the normal operating value, and the second fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery fault of the non-faulty battery cabinet is marked as level 2 overhaul.

[0080] Replace all of them. A short circuit occurred between the battery cabinets. The current of all battery cabinets has greatly exceeded the normal operating value, and the third fuse has blown. All batteries in the faulty battery cabinet and the non-faulty battery cabinet need to be replaced.

[0081] When a short circuit occurs inside the battery box, only the faulty battery cabinet will flow a large current, while the current of other non-faulty battery cabinets is still within an acceptable range. If the fault is removed in a short time, the battery performance will not be greatly affected. Therefore, it is recommended that all batteries in the faulty battery cabinet be replaced, while the batteries in the non-faulty battery cabinet can continue to be used, marked as the first-level maintenance level.

[0082] When a short circuit occurs between battery boxes, the current of the faulty and non-faulty battery cabinets will further increase. However, the battery capacity used in this article is large, and the battery performance may not be affected too much if the removal speed is fast. Therefore, it is recommended that all batteries in the faulty battery cabinet be replaced, while the batteries in the non-faulty battery cabinet can continue to be used, marked as the second-level maintenance level.

[0083] When a short circuit occurs between battery cabinets, the current of all battery cabinets has greatly exceeded the normal operating value. Even if the fault is removed in time, the battery will still cause abnormal conditions such as diaphragm decomposition and metal lithium dendrite growth due to excessive current. At this time, it is recommended to replace all batteries in the battery module. Therefore, although the probability of short circuit between battery cabinets is small, once it occurs, it will cause huge harm and losses. Table 1 shows the inspection and maintenance solutions for different types of faults.

[0084] Table 1 Different types of fault inspection and maintenance solutions

[0085] Battery box internal short circuit Short circuit between battery boxes Short circuit between battery cabinets Faulty battery Replace All Replace All Replace All Non-faulty battery Level 1 maintenance Level 2 maintenance Replace All

[0086] Embodiment 2:

[0087] This embodiment provides a short circuit fault monitoring and protection system suitable for a large-capacity battery pack, including:

[0088] A short-circuit fault detection architecture building module is used to build a battery short-circuit fault monitoring architecture, wherein the battery short-circuit fault monitoring architecture includes: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, and a battery monitoring unit installed in the battery box;

[0089] The battery information collection module collects the voltage, current, battery charge state and temperature change of the battery box through the battery monitoring unit installed in the battery box, collects the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet, and the battery management system in the control cabinet summarizes the information collected by the battery monitoring unit and the main control box and outputs the results through the fault diagnosis unit to guide fault handling;

[0090] A fuse arrangement module is provided, wherein a first fuse is installed at the positive and negative busbars of the battery pack, a second fuse is installed at the positive position of each battery box, and a third fuse is installed at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault;

[0091] The diagnosis and repair suggestion module confirms the different impacts of the short-circuit fault on batteries in different positions of the battery module based on the short-circuit fault diagnosis results output by the battery management system and the fusing actions of the first fuse, the second fuse, and the third fuse, and repairs or replaces the faulty batteries according to the short-circuit fault repair and maintenance plan.

[0092] Embodiment three:

[0093] This embodiment provides an electronic device having a computer program stored thereon. When the computer program is executed by a processor, a short-circuit fault monitoring and protection method applicable to a large-capacity battery pack as described in any embodiment of the present invention is implemented.

[0094] Embodiment 4:

[0095] This embodiment provides a computer-readable medium for storing one or more programs. When the one or more programs are executed by the one or more processors, the one or more processors implement a short-circuit fault monitoring and protection method suitable for a large-capacity battery pack as described in any embodiment of the present invention.

[0096] In the embodiments of the present application, "at least one" refers to one or more, and "more than one" refers to two or more. "And / or" describes the association relationship of associated objects, indicating that three relationships may exist. For example, A and / or B can represent the existence of A alone, the existence of A and B at the same time, and the existence of B alone. Among them, A and B can be singular or plural. The character " / " generally indicates that the previous and next associated objects are in an "or" relationship. "At least one of the following" and similar expressions refer to any combination of these items, including any combination of single or plural items. For example, at least one of a, b and c can be represented by: a, b, c, a and b, a and c, b and c, or a and b and c, where a, b, c can be single or multiple.

[0097] Those of ordinary skill in the art will appreciate that the various units and algorithm steps described in the embodiments disclosed herein can be implemented in a combination of electronic hardware, computer software, and electronic hardware. Whether these functions are performed in hardware or software depends on the specific application and design constraints of the technical solution. Professional and technical personnel can use different methods to implement the described functions for each specific application, but such implementation should not be considered to be beyond the scope of this application.

[0098] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working processes of the systems, devices and units described above can refer to the corresponding processes in the aforementioned method embodiments and will not be repeated here.

[0099] In several embodiments provided in the present application, if any function 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 storage medium. Based on this understanding, the technical solution of the present application, or the part that contributes to the prior art or the part of the technical solution, can be embodied in the form of a software product, which is stored in a storage medium and includes several instructions for a computer device (which can be a personal computer, a server, or a network device, etc.) to perform all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (Read-Only Memory; hereinafter referred to as: ROM), random access memory (Random Access Memory; hereinafter referred to as: RAM), disk or optical disk, and other media that can store program codes.

[0100] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent structure or equivalent process transformation made using the contents of the present invention specification and drawings, or directly or indirectly applied in other related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A short circuit fault monitoring and protection method suitable for large-capacity battery packs, characterized in that: The following steps are involved: Step S1, constructing a battery short circuit fault monitoring architecture, including: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, a battery box, and a battery monitoring unit installed in the battery box; Step S2, collecting the voltage, current, battery state of charge and temperature change of the battery box through the battery monitoring unit, collecting the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet; summarizing the information collected by the battery monitoring unit and the main control box through the battery management system in the control cabinet and outputting it to the fault diagnosis unit, and outputting the short circuit fault diagnosis result through the fault diagnosis unit; Step S3, installing a first fuse at the positive and negative busbars of the battery pack, installing a second fuse at the positive position of each battery box, and installing a third fuse at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault; Step S4, confirming the different effects of the short-circuit fault on batteries at different locations based on the short-circuit fault diagnosis result and the blowing actions of the first fuse, the second fuse, and the third fuse, and determining a corresponding short-circuit fault inspection and maintenance plan.

2. A short circuit fault monitoring and protection method suitable for a large-capacity battery pack according to claim 1, characterized in that: The first fuse is used to protect the power module of the battery pack: the melting threshold of the first fuse is set according to the current value flowing through the positive and negative busbars of the battery pack. The specific calculation formula of the current value flowing through the positive and negative busbars of the battery pack is as follows: Among them, I mid is the intermediate calculation amount, and the expression is: In the formula, is the current value flowing through the positive and negative busbars of the battery pack, are the output power, voltage and current of battery pack a respectively, k is the number of short-circuited batteries, there are (nk) batteries outside the short-circuit point, where k<n, R f is the transition resistance of short circuit fault, I f is the short-circuit current, E is the electromotive force of the battery cell, m is the number of battery packs in parallel in the battery pack, n is the total number of batteries, R n is the internal resistance of a single battery.

3. A short circuit fault monitoring and protection method suitable for a large-capacity battery pack according to claim 1, characterized in that: The second fuse is used to cut off the short circuit between the battery box and the battery cabinet; the fusing threshold of the second fuse is set according to the current value flowing through the positive pole of the battery box. The specific calculation formula of the current value flowing through the positive pole of the battery box is as follows: Where: is the current value at the positive pole of the battery box, I c is the internal current of the battery pack when k batteries in the battery pack are short-circuited.

4. A short-circuit fault monitoring and protection method for a large-capacity battery pack according to claim 1, characterized in that: The third fuse is used to cut off the short-circuit current between the battery cabinets; the third fuse is connected in series with the second fuse, and the melting threshold of the third fuse is the same as the melting threshold of the second fuse.

5. A short circuit fault monitoring and protection method suitable for a large-capacity battery pack according to claim 1, characterized in that: The faulty battery is repaired or replaced according to the short-circuit fault repair and maintenance plan, wherein the fault repair and maintenance plan includes: primary repair, secondary repair and battery replacement. The specific fault repair and maintenance plan is as follows: Level 1 overhaul: short circuit failure inside the battery box. The fault monitoring unit detects a large current in the faulty battery cabinet, and the first fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery failure in the non-faulty battery cabinet is marked as level 1 overhaul. Level 2 overhaul: short circuit fault between battery boxes. The fault monitoring unit detects that the current of the faulty and non-faulty battery cabinets increases, but it is within the normal operating value, and the second fuse blows. All batteries in the faulty battery cabinet are replaced, while the batteries in the non-faulty battery cabinet can continue to be used. The maintenance plan for the battery fault of the non-faulty battery cabinet is marked as level 2 overhaul. Replace all of them. A short circuit occurred between the battery cabinets. The current of all battery cabinets has greatly exceeded the normal operating value, and the third fuse has blown. All batteries in the faulty battery cabinet and the non-faulty battery cabinet need to be replaced.

6. A short circuit fault monitoring and protection system suitable for large-capacity battery packs, characterized in that: include: A short-circuit fault detection architecture building module is used to build a battery short-circuit fault monitoring architecture, wherein the battery short-circuit fault monitoring architecture includes: a control cabinet, a battery cabinet, a battery management system and a fault diagnosis unit installed in the control cabinet, a main control box installed in the battery cabinet, and a battery monitoring unit installed in the battery box; The battery information collection module collects the voltage, current, battery charge state and temperature change of the battery box through the battery monitoring unit installed in the battery box, collects the voltage and current level of the battery cabinet as a whole through the main control box installed in the battery cabinet, and the battery management system in the control cabinet summarizes the information collected by the battery monitoring unit and the main control box and outputs the results through the fault diagnosis unit to guide fault handling; A fuse arrangement module is provided, wherein a first fuse is installed at the positive and negative busbars of the battery pack, a second fuse is installed at the positive position of each battery box, and a third fuse is installed at the positive and negative positions of each battery cabinet; the first fuse, the second fuse and the third fuse are used to suppress the development of a short circuit fault; The diagnosis and repair suggestion module confirms the different impacts of the short-circuit fault on batteries in different positions of the battery module based on the short-circuit fault diagnosis results output by the battery management system and the fusing actions of the first fuse, the second fuse, and the third fuse, and repairs or replaces the faulty batteries according to the short-circuit fault repair and maintenance plan.

7. A short-circuit fault monitoring and protection system for a large-capacity battery pack according to claim 6: the first fuse is used to protect the power module of the battery pack: the melting threshold of the first fuse is set according to the current value flowing through the positive and negative busbars of the battery pack, and the specific calculation formula of the current value is as follows: in, I mid is the intermediate calculation amount, and the expression is: In the formula, is the current value flowing through the positive and negative busbars of the battery pack, are the output power, voltage and current of battery pack a respectively, k is the number of short-circuited batteries, there are (nk) batteries outside the short-circuit point, where k<n, R f is the transition resistance of short circuit fault, I f is the short-circuit current, E is the electromotive force of the battery cell, m is the number of battery packs in parallel in the battery pack, n is the total number of batteries, R n is the internal resistance of a single battery.

8. According to claim 6, a short-circuit fault monitoring and protection system for a large-capacity battery pack: the second fuse is used to cut off the short-circuit loop between the battery box and the battery cabinet; the fusing threshold of the second fuse is set according to the current value flowing through the positive pole of the battery box, and the specific calculation formula of the current value is as follows: Where: is the current value at the positive pole of the battery box, I c is the internal current of the battery pack when k batteries in the battery pack are short-circuited.

9. An electronic device comprising a memory, a processor, and a computer program stored in the memory and executable on the processor, characterized in that: When the processor executes the program, a short-circuit fault monitoring and protection method suitable for a large-capacity battery pack as described in any one of claims 1 to 5 is implemented.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, a short-circuit fault monitoring and protection method suitable for a large-capacity battery pack is implemented as described in any one of claims 1 to 5.

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