A control method and control device for a power battery fuse

Abstract

This application provides a control method and control device for a power battery fuse. The control method is applied to a BMS (Battery Management System) in a power battery system. The power battery system includes a fuse and a current sensor installed on the high-voltage main circuit of the power battery system. The control method includes: acquiring the current of the high-voltage main circuit through the current sensor; determining whether the high-voltage main circuit has reached the fusing condition based on the current; and controlling the fuse to open if the high-voltage main circuit has reached the fusing condition. This control method can shorten the time it takes for the high-voltage main circuit to be disconnected, thereby improving the safety of the high-voltage main circuit.

Description

Technical Field

[0001] This application relates to the field of power battery technology, and in particular to a control method and control device for a power battery fuse. Background Technology

[0002] With the development of electric vehicles, they are becoming increasingly widely used in daily life. However, electric vehicles frequently encounter safety issues, such as short circuits and spontaneous combustion after collisions or during charging. These safety problems are all caused by the power batteries of electric vehicles, making the safety of electric vehicle power batteries a problem that cannot be ignored.

[0003] Currently, most power batteries use high-voltage relays and fuses to jointly achieve the high-voltage cutoff function, thereby ensuring the high-voltage safety of the power battery. The high-voltage relay is an active protection device, which actively cuts off the high voltage of the power battery through low-voltage disconnection. However, when the current in the high-voltage circuit reaches a relatively large current (e.g., 1500A) relative to the high-voltage relay, disconnecting the high-voltage relay carries the risk of relay sticking, failing to completely guarantee the high-voltage cutoff of the power battery. To ensure the high-voltage cutoff of the power battery under such circumstances, a fuse is added. The fuse is a passive protection device. When the aforementioned current occurs in the high-voltage circuit, because the current that is large for the high-voltage relay is small for the fuse, the fuse will not immediately disconnect, but will accumulate heat, only melting when the heat accumulation reaches a certain value. However, the time for the fuse to accumulate heat and melt is generally on the order of seconds. Therefore, the existing fuses have a relatively long melting time in the event of a fault in the high-voltage circuit of the power battery system, resulting in a longer disconnection time of the high-voltage main circuit and reducing the safety of the high-voltage main circuit. Summary of the Invention

[0004] In view of this, the purpose of this application is to provide a control method and control device for a power battery fuse, so as to shorten the time when the high-voltage main circuit is disconnected and improve the safety of the high-voltage main circuit.

[0005] In a first aspect, embodiments of this application provide a control method for a power battery fuse, applied to a BMS in a power battery system, wherein the power battery system includes: a fuse and a current sensor disposed on the high-voltage main circuit of the power battery system; the control method includes: The current in the high-voltage main circuit is obtained through the current sensor; Based on the current in the high-voltage main circuit, determine whether the high-voltage main circuit has reached the fuse-breaking condition; If the high-voltage main circuit reaches the melting condition, the fuse is controlled to open.

[0006] Optionally, the current sensor includes a first current sensor, the first current sensor having a first range; determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit includes: Determine whether the current in the high-voltage main circuit exceeds the upper limit of the first range. If the current in the high-voltage main circuit does not exceed the upper limit of the first range, determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current in the high-voltage main circuit and the preset threshold.

[0007] Optionally, determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit and a preset threshold includes: Determine whether the current of the high-voltage main circuit is greater than a first preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the first preset threshold reaches a first preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; Determine whether the current of the high-voltage main circuit is greater than a second preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the second preset threshold reaches a second preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the first preset threshold is less than the second preset threshold, the second preset threshold is less than the upper limit of the first range, and the first preset time is greater than the second preset time.

[0008] Optionally, the control method further includes: If the current in the high-voltage main circuit exceeds the upper limit of the first range, the moment when the current in the high-voltage main circuit exceeds the upper limit of the first range shall be taken as the start sampling moment. Obtain the parameter data of the battery pack at the start sampling time and the parameter data of the battery pack at each sampling time after the start sampling time; For each sampling time, the difference between the parameter data of the battery pack at that sampling time and the parameter data of the battery pack at the start of sampling time is determined, and the difference value is determined as the difference data of the parameter data of the battery pack at that sampling time. Based on the differences in the parameter data of the battery pack, it is determined whether the high-voltage main circuit has reached the fuse-breaking condition.

[0009] Optionally, the parameter data of the battery pack includes at least one of the following: the total voltage of the battery pack and the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

[0010] Optionally, determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the difference data of the battery pack parameter data includes: Determine whether the time for which the current in the high-voltage main circuit exceeds the upper limit of the first range reaches a third preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; The parameter data of the battery pack includes the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack. Determine whether the total voltage difference is greater than a third preset threshold and whether the time during which the total voltage difference is greater than the third preset threshold reaches a fourth preset time; If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; The parameter data of the battery pack includes the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

[0011] Determine whether the minimum single-cell voltage difference is greater than a fourth preset threshold and whether the time for which the minimum single-cell voltage difference is greater than the fourth preset threshold reaches a fifth preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the third preset threshold is greater than the upper limit of the first range, the fourth preset threshold is greater than the third preset threshold, the third preset time is greater than the fourth preset time, and the fourth preset time is greater than or equal to the fifth preset time.

[0012] Optionally, the current sensor further includes a second current sensor, the second current sensor having a second range; the upper limit of the second range is less than the upper limit of the first range. The first preset threshold is less than the upper limit of the second range, and the second preset threshold is greater than the upper limit of the second range and less than the upper limit of the first range.

[0013] Secondly, embodiments of this application provide a control device for a power battery fuse. The control device is applied to a power battery system, which includes: a fuse and a current sensor disposed on the high-voltage main circuit of the power battery system; the control device includes: The acquisition module is used to acquire the current of the high-voltage main circuit through the current sensor; The judgment module is used to determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit; The control module is used to control the fuse to open if the high-voltage main circuit reaches the melting condition.

[0014] Thirdly, embodiments of this application provide a vehicle, including: a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. When the machine-readable instructions are executed by the processor, the steps of the control method for the power battery fuse described above are performed.

[0015] Fourthly, embodiments of this application provide a computer-readable storage medium storing a computer program that, when executed by a processor, performs the steps of the control method for a power battery fuse as described above.

[0016] This application provides a control method and control device for a power battery fuse. The method acquires the current in the high-voltage main circuit using a current sensor; based on the current in the high-voltage main circuit, it determines whether the high-voltage main circuit has reached the fusing condition; if the high-voltage main circuit has reached the fusing condition, it controls the fuse to disconnect. This control method, based on the current in the high-voltage main circuit, directly controls the fuse to disconnect according to a predetermined strategy. Compared to existing fuses that require heat accumulation to reach a certain value before melting, this method directly disconnects the fuse in a shorter time (typically on the order of milliseconds), thus shortening the time the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit.

[0017] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description

[0018] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This invention provides a schematic diagram of the structure of a power battery system according to an exemplary embodiment of the present application. Figure 2 A flowchart illustrating a control method for a power battery fuse provided in an exemplary embodiment of this application is shown. Figure 3 A schematic flowchart illustrating the steps of controlling the tripping of a fuse according to an exemplary embodiment of this application is shown. Figure 4 This invention provides a schematic diagram of the structure of a control device for a power battery fuse according to an exemplary embodiment of the present application. Figure 5 A schematic diagram of the structure of a vehicle provided by an exemplary embodiment of this application is shown. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. Based on the embodiments of this application, every other embodiment obtained by those skilled in the art without inventive effort falls within the scope of protection of this application.

[0021] Based on this, this application provides a control method for a power battery fuse. The control method, based on the current of the high-voltage main circuit, directly controls the fuse to disconnect according to a predetermined strategy. Compared with existing fuses that require heat accumulation to reach a certain value before melting, the control method allows the fuse to disconnect directly in a shorter time (generally on the order of milliseconds), thus shortening the time when the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit.

[0022] For ease of understanding, an exemplary embodiment of this application will first be described.

[0023] Please see Figure 1 , Figure 1 A schematic diagram of the structure of a power battery system provided by an exemplary embodiment of this application is shown.

[0024] like Figure 1As shown in an exemplary embodiment of this application, the power battery system includes: BMS10, a fuse 20 disposed on the high-voltage main circuit of the power battery system, and a current sensor 30.

[0025] Here, the number of current sensors 10 is at least one. When there are multiple current sensors, the types of current sensors can be different. For example, the types of current sensors can include shunt current sensors and Hall current sensors. By setting multiple current sensors, a backup function can be provided, so that in the event of a failure of one current sensor, another current sensor can also disconnect the high-voltage main circuit, ensuring the safety of the high-voltage main circuit. Furthermore, by setting the types of multiple current sensors to different types, it is possible to prevent other current sensors from failing for the same reason if one current sensor fails for one reason, thereby further ensuring the safety of the high-voltage main circuit.

[0026] The power battery system also includes a high-voltage relay (including a main positive relay, a pre-charge relay, and a main negative relay) and a pre-charge resistor, wherein the high-voltage relay is disposed on the high-voltage circuit of the power battery system.

[0027] In addition, such as Figure 1 As shown, in another exemplary embodiment of this application, the power battery system may further include a first voltage sampler 40, wherein the first voltage sampler 40 is used to collect the total voltage of the battery pack, for example, the first voltage sampler may be an HMV.

[0028] In addition, such as Figure 1 As shown, in another exemplary embodiment of this application, the power battery system may further include a second voltage sampler 50, wherein the second voltage sampler 50 is used to collect the cell voltage of each battery cell in the battery pack. For example, the second voltage sampler may be a CMU.

[0029] In the case where the power battery system includes BMS10, fuse 20, current sensor 30, first voltage sampler 40 and second voltage sampler 50, the BMS10, the fuse 20, the current sensor 30, the first voltage sampler 40 and the second voltage sampler 50 are connected via a CAN bus.

[0030] The following describes a control method for a power battery fuse provided by an exemplary embodiment of this application. The control method is applied to the BMS (Battery Management System) in the aforementioned power battery system.

[0031] Please see Figure 2 , Figure 2 A flowchart illustrating a control method for a power battery fuse provided in an exemplary embodiment of this application is shown.

[0032] like Figure 2 As shown, the control method includes: S100. Obtain the current of the high-voltage main circuit through the current sensor; Here, when there is only one current sensor (the first current sensor), the current of the high-voltage main circuit is obtained through the first current sensor. When there are multiple current sensors, such as two (the first current sensor and the second current sensor), since each current sensor measures the current of the high-voltage main circuit, the current measured by each current sensor should theoretically be the same. Therefore, the current of the high-voltage main circuit can be obtained through either the first current sensor or the second current sensor. Obtaining the current of the high-voltage main circuit through either the first current sensor or the second current sensor can be understood as pre-setting whether to obtain the current through the first current sensor or the second current sensor. If it is pre-set to obtain the current through the first current sensor, then the current of the high-voltage main circuit measured by the first current sensor is determined as the current of the high-voltage main circuit. If it is pre-set to obtain the current through the second current sensor, then the current of the high-voltage main circuit measured by the second current sensor is determined as the current of the high-voltage main circuit.

[0033] S200. Based on the current of the high-voltage main circuit, determine whether the high-voltage main circuit has reached the fusing condition; S300 If the high-voltage main circuit reaches the melting condition, control the fuse to open.

[0034] The control method provided in this application acquires the current of the high-voltage main circuit through the current sensor; based on the current of the high-voltage main circuit, it determines whether the high-voltage main circuit has reached the fusing condition; if the high-voltage main circuit has reached the fusing condition, it controls the fuse to open. By directly controlling the fuse to open based on the current of the high-voltage main circuit according to a predetermined strategy, compared to existing fuses that require heat accumulation to reach a certain value before melting, the time for controlling the fuse to open directly is shorter (generally on the order of milliseconds), thus shortening the time when the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit.

[0035] The following will describe in detail the specific implementation of step S200, which involves determining whether the high-voltage main circuit has reached the fusing condition based on the current of the high-voltage main circuit.

[0036] As an example, the current sensor includes a first current sensor, the first current sensor having a first range.

[0037] In one embodiment, when the current sensor includes a first current sensor, step S200, determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit, may include the following steps: S210. Determine whether the current in the high-voltage main circuit exceeds the upper limit of the first range. S220. If the current of the high-voltage main circuit does not exceed the upper limit of the first range, determine whether the high-voltage main circuit has reached the fuse condition based on the current of the high-voltage main circuit and the preset threshold.

[0038] Furthermore, when the current in the high-voltage main circuit exceeds the upper limit of the first range, the first current sensor can no longer quantitatively measure the current in the high-voltage main circuit, and therefore cannot determine whether the high-voltage main circuit has reached the melting condition based on the current in the high-voltage main circuit. To solve this problem, this application provides a method for determining whether the high-voltage main circuit has reached the melting condition when the current in the high-voltage main circuit exceeds the upper limit of the first range.

[0039] In another embodiment, when the current sensor includes a first current sensor, step S200, determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit, may further include the following steps: S230. If the current of the high-voltage main circuit exceeds the upper limit of the first range, the moment when the current of the high-voltage main circuit exceeds the upper limit of the first range is taken as the start sampling moment; obtain the parameter data of the battery pack at the start sampling moment and the parameter data of the battery pack at each sampling moment after the start sampling moment. S240. For each sampling time, determine the difference between the parameter data of the battery pack at that sampling time and the parameter data of the battery pack at the start sampling time, and determine the difference value as the difference data of the parameter data of the battery pack at that sampling time. As an example, the parameter data of the battery pack may include at least one of the following: the total voltage of the battery pack and the minimum single-cell voltage of the battery cells in the battery pack; Here, the difference value may include the difference value, or other values ​​that can reflect the difference between the parameter data of the battery pack at each sampling time and the parameter data of the battery pack at the start of sampling. This application does not limit this.

[0040] It is understood that when the difference value is a difference, the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

[0041] S250. Based on the difference data of the parameter data of the battery pack, determine whether the high-voltage main circuit has reached the fuse condition.

[0042] The following will describe the steps for determining whether the high-voltage main circuit has reached the fusing condition based on the current of the high-voltage main circuit and a preset threshold, when the current of the high-voltage main circuit does not exceed the upper limit of the first range.

[0043] As a first example, it is determined whether the current of the high-voltage main circuit is greater than a first preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the first preset threshold reaches a first preset time; if so, it is determined that the high-voltage main circuit has reached the fuse-breaking condition. As a second example, it is determined whether the current of the high-voltage main circuit is greater than a second preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the second preset threshold reaches a second preset time; if so, it is determined that the high-voltage main circuit has reached the fuse-breaking condition.

[0044] Here, the first preset threshold is less than the second preset threshold, the second preset threshold is less than the upper limit of the first range, and the first preset time is greater than the second preset time.

[0045] As an example, if the current sensor includes a second current sensor in addition to the first current sensor (i.e., if there are two current sensors), assuming that the range of the second current sensor is the second range; and the upper limit of the second range is less than the upper limit of the first range; then the first preset threshold and the second preset threshold can be configured as follows: the first preset threshold is less than the upper limit of the second range, and the second preset threshold is greater than the upper limit of the second range and less than the upper limit of the first range.

[0046] In this way, it is possible to determine whether the high-voltage main circuit has reached the melting condition based on the current of the high-voltage main circuit, provided that the current of the high-voltage main circuit does not exceed the upper limit of the first range. The following describes the steps for determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the difference data of the battery pack parameter data when the current in the high-voltage main circuit exceeds the upper limit of the first range.

[0047] As a third example, it is determined whether the time for which the current in the high-voltage main circuit exceeds the upper limit of the first range reaches a third preset time; if so, it is determined that the high-voltage main circuit has reached the fuse-breaking condition. As a fourth example, the parameter data of the battery pack includes the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; in this case, the step of determining whether the high-voltage main circuit has reached the fuse condition based on the difference data of the parameter data of the battery pack may include: determining whether the total voltage difference is greater than a third preset threshold and whether the time for which the total voltage difference is greater than the third preset threshold reaches a fourth preset time; if so, then determining that the high-voltage main circuit has reached the fuse condition.

[0048] Here, the current in the high-voltage main circuit is proportional to the total voltage difference. The larger the current in the high-voltage main circuit, the larger the total voltage difference; conversely, the smaller the current in the high-voltage main circuit, the smaller the total voltage difference. Therefore, it can be understood that, assuming the upper limit of the first range is 2000A, the total voltage difference is different when the current in the high-voltage main circuit reaches 2500A and 3000A, with the total voltage difference being even larger when the current in the high-voltage main circuit reaches 3000A. Therefore, by setting a third preset threshold, the current situation in the high-voltage main circuit can be determined. That is, when the total voltage difference is greater than the third preset threshold, it indicates that the current in the high-voltage main circuit has reached a certain value, for example, 3000A.

[0049] As a fifth example, the parameter data of the battery pack includes the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage; in this case, the step of determining whether the high-voltage main circuit has reached the fuse condition based on the difference data of the parameter data of the battery pack may include: determining whether the minimum single-cell voltage difference is greater than a fourth preset threshold and whether the time for which the minimum single-cell voltage difference is greater than the fourth preset threshold reaches a fifth preset time; if so, it is determined that the high-voltage main circuit has reached the fuse condition.

[0050] Here, the third preset threshold is greater than the upper limit of the first range, the fourth preset threshold is greater than the third preset threshold, the third preset time is greater than the fourth preset time, and the fourth preset time is greater than or equal to the fifth preset time.

[0051] Here, the current in the high-voltage main circuit is proportional to the minimum individual voltage difference. The larger the current in the high-voltage main circuit, the larger the minimum individual voltage difference; conversely, the smaller the current in the high-voltage main circuit, the smaller the minimum individual voltage difference. Therefore, it can be understood that, assuming the upper limit of the first range is 2000A, the minimum individual voltage difference is different when the current in the high-voltage main circuit reaches 2700A and 3500A, with the minimum individual voltage difference being larger when the current in the high-voltage main circuit reaches 3500A. Therefore, by setting a fourth preset threshold, the current situation in the high-voltage main circuit can be determined. That is, when the minimum individual voltage difference is greater than the fourth preset threshold, it indicates that the current in the high-voltage main circuit has reached a certain value, for example, 3500A.

[0052] It is understood that the solution in this application may include at least one of the conditions corresponding to the five examples mentioned above.

[0053] The following describes the steps for controlling the fuse to trip under the conditions corresponding to all five examples mentioned above in this application. The steps for controlling the fuse to trip under the conditions corresponding to any one or more of the five examples mentioned above in this application can be referred to the steps of those examples.

[0054] Please see Figure 3 , Figure 3 This illustration shows a schematic flowchart of steps for controlling the tripping of a fuse according to an exemplary embodiment of this application. The conditions for determining whether the high-voltage main circuit has reached the tripping condition based on the difference data of the battery pack's parameter data include the conditions corresponding to all five examples described above.

[0055] like Figure 3As shown, the steps for controlling the fuse to disconnect may include: in step S100, acquiring the current of the high-voltage main circuit through the current sensor; then in step S210, determining whether the current of the high-voltage main circuit exceeds the upper limit of the first range; on the one hand, if the current of the high-voltage main circuit does not exceed the upper limit of the first range, then in step S221, determining whether the current of the high-voltage main circuit is greater than a first preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the first preset threshold has reached a first preset time; if yes, then directly determining that the high-voltage main circuit has reached the fusing condition, and controlling the fuse to disconnect in step S300; if no, then in step S222, determining whether the current of the high-voltage main circuit is greater than a second preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the second preset threshold has reached a second preset time; if yes, then directly determining that the high-voltage main circuit has reached the fusing condition, and controlling the fuse to disconnect in step S300; if no, then returning to step S210 to determine whether the current of the high-voltage main circuit exceeds the upper limit of the first range. On the other hand, if the current in the high-voltage main circuit exceeds the upper limit of the first range, then in step S230, the moment when the current in the high-voltage main circuit exceeds the upper limit of the first range is taken as the start sampling moment, and the parameter data of the battery pack at the start sampling moment and the parameter data of the battery pack at each sampling moment after the start sampling moment are obtained; then in step S240, for each sampling moment, the difference value between the parameter data of the battery pack at that sampling moment and the parameter data of the battery pack at the start sampling moment is determined, and the difference value is determined as the difference data of the parameter data of the battery pack at that sampling moment; then in step S251, it is determined whether the time when the current in the high-voltage main circuit exceeds the upper limit of the first range has been reached. If the third preset time is met, the high-voltage main circuit is directly determined to have reached the fuse-breaking condition. If not, in step S252, it is determined whether the total voltage difference is greater than the third preset threshold and whether the time for which the total voltage difference is greater than the third preset threshold has reached the fourth preset time. If yes, the high-voltage main circuit is directly determined to have reached the fuse-breaking condition. If not, in step S253, it is determined whether the minimum single-unit voltage difference is greater than the fourth preset threshold and whether the time for which the minimum single-unit voltage difference is greater than the fourth preset threshold has reached the fifth preset time. If yes, the high-voltage main circuit is directly determined to have reached the fuse-breaking condition. If not, the process returns to step S210 to determine whether the current of the high-voltage main circuit exceeds the upper limit of the first range.

[0056] In summary, the control method for a power battery fuse provided in this application can directly control the fuse to disconnect based on the current in the high-voltage main circuit and according to a predetermined strategy. Compared with existing fuses that require heat accumulation to reach a certain value before melting, the direct disconnection time of the fuse is shorter (generally on the order of milliseconds), thus shortening the time when the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit. Furthermore, in the process of directly controlling the fuse to disconnect according to the predetermined strategy, the preset time is shorter when the current in the high-voltage main circuit is larger. In this way, the requirement for determining that the high-voltage main circuit has reached the melting condition can be reduced when the current is larger, further shortening the time when the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit.

[0057] Based on the same inventive concept, this application also provides a control device for a power battery fuse corresponding to the control method of the power battery fuse described above. Since the principle of the device in this application is similar to the method in this application, the implementation of the device can refer to the implementation of the method, and the repeated parts will not be described again.

[0058] Please see Figure 4 , Figure 4 A schematic diagram of the structure of a control device for a power battery fuse provided in an exemplary embodiment of this application is shown.

[0059] like Figure 4 As shown, the control device includes: The acquisition module 410 is used to acquire the current of the high-voltage main circuit through the current sensor; The judgment module 420 is used to determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit. The control module 430 is used to control the fuse to open if the high-voltage main circuit reaches the melting condition.

[0060] Optionally, the current sensor includes a first current sensor, the first current sensor having a first range; the judgment module 420 is specifically used for: Determine whether the current in the high-voltage main circuit exceeds the upper limit of the first range. If the current in the high-voltage main circuit does not exceed the upper limit of the first range, determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current in the high-voltage main circuit and the preset threshold.

[0061] Optionally, the determination module 420 is specifically used for: Determine whether the current of the high-voltage main circuit is greater than a first preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the first preset threshold reaches a first preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; Determine whether the current of the high-voltage main circuit is greater than a second preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the second preset threshold reaches a second preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the first preset threshold is less than the second preset threshold, the second preset threshold is less than the upper limit of the first range, and the first preset time is greater than the second preset time.

[0062] Optionally, the determination module 420 is further configured to: If the current in the high-voltage main circuit exceeds the upper limit of the first range, the moment when the current in the high-voltage main circuit exceeds the upper limit of the first range shall be taken as the start sampling moment. Obtain the parameter data of the battery pack at the start sampling time and the parameter data of the battery pack at each sampling time after the start sampling time; For each sampling time, the difference between the parameter data of the battery pack at that sampling time and the parameter data of the battery pack at the start of sampling time is determined, and the difference value is determined as the difference data of the parameter data of the battery pack at that sampling time. Based on the differences in the parameter data of the battery pack, it is determined whether the high-voltage main circuit has reached the fuse-breaking condition.

[0063] Optionally, the parameter data of the battery pack includes at least one of the following: the total voltage of the battery pack and the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

[0064] Optionally, the determination module 420 is specifically used for: Determine whether the time for which the current in the high-voltage main circuit exceeds the upper limit of the first range reaches a third preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; The parameter data of the battery pack includes the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack. Determine whether the total voltage difference is greater than a third preset threshold and whether the time during which the total voltage difference is greater than the third preset threshold reaches a fourth preset time; If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; The parameter data of the battery pack includes the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

[0065] Determine whether the minimum single-cell voltage difference is greater than a fourth preset threshold and whether the time for which the minimum single-cell voltage difference is greater than the fourth preset threshold reaches a fifth preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the third preset threshold is greater than the upper limit of the first range, the fourth preset threshold is greater than the third preset threshold, the third preset time is greater than the fourth preset time, and the fourth preset time is greater than or equal to the fifth preset time.

[0066] Optionally, the current sensor further includes a second current sensor, the second current sensor having a second range; the upper limit of the second range is less than the upper limit of the first range. The first preset threshold is less than the upper limit of the second range, and the second preset threshold is greater than the upper limit of the second range and less than the upper limit of the first range.

[0067] The control device provided in this application embodiment acquires the current of the high-voltage main circuit through the current sensor; based on the current of the high-voltage main circuit, it determines whether the high-voltage main circuit has reached the fusing condition; if the high-voltage main circuit has reached the fusing condition, it controls the fuse to open. By directly controlling the fuse to open based on the current of the high-voltage main circuit according to a predetermined strategy, compared to existing fuses that require heat accumulation to reach a certain value before melting, the time for controlling the fuse to open directly is shorter (generally on the order of milliseconds), thus shortening the time when the high-voltage main circuit is disconnected and improving the safety of the high-voltage main circuit.

[0068] Please see Figure 5 , Figure 5 This is a schematic diagram of the structure of a vehicle provided in an embodiment of this application. Figure 5 As shown, the vehicle 500 includes a processor 510, a memory 520, and a bus 530.

[0069] The memory 520 stores machine-readable instructions that can be executed by the processor 510. When the electronic device is running, the processor 510 and the memory 520 communicate via the bus 530. When the machine-readable instructions are executed by the processor 510, the steps of the control method for the power battery fuse as described in the above method embodiment can be executed. For specific implementation details, please refer to the method embodiment, which will not be repeated here.

[0070] This application also provides a computer-readable storage medium storing a computer program. When the computer program is run by a processor, it can execute the steps of the control method for the power battery fuse as described in the above method embodiments. For specific implementation details, please refer to the method embodiments, which will not be repeated here.

[0071] Those skilled in the art will understand that, for the sake of convenience and brevity, the specific working processes of the systems, devices, and units described above can be referred to the corresponding processes in the foregoing method embodiments, and will not be repeated here.

[0072] In the several embodiments provided in this application, it should be understood that the disclosed systems, apparatuses, and methods can be implemented in other ways. The apparatus embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and in actual implementation, there may be other division methods. Furthermore, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Additionally, the shown or discussed mutual couplings, direct couplings, or communication connections may be through some communication interfaces; indirect couplings or communication connections between devices or units may be electrical, mechanical, or other forms.

[0073] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple network units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0074] In addition, the functional units in the various embodiments of this application can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit.

[0075] If the aforementioned functions are implemented as software functional units and sold or used as independent products, they can be stored in a processor-executable, non-volatile, computer-readable storage medium. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, or a portion of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks.

[0076] Finally, it should be noted that the above-described embodiments are merely specific implementations of this application, used to illustrate the technical solutions of this application, and not to limit them. The scope of protection of this application is not limited thereto. Although this application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that any person skilled in the art can still modify or easily conceive of changes to the technical solutions described in the foregoing embodiments, or make equivalent substitutions for some of the technical features, within the scope of the technology disclosed in this application. Such modifications, changes, or substitutions do not cause the essence of the corresponding technical solutions to deviate from the spirit and scope of the technical solutions of the embodiments of this application, and should all be covered within the scope of protection of this application. Therefore, the scope of protection of this application should be determined by the scope of the claims.

Claims

1. A control method for a power battery fuse, characterized in that, A BMS (Battery Management System) is applied to a power battery system, wherein the power battery system includes: a fuse and a current sensor disposed on the high-voltage main circuit of the power battery system; the control method includes: The current in the high-voltage main circuit is obtained through the current sensor; Based on the current of the high-voltage main circuit, determine whether the high-voltage main circuit has reached the fuse-breaking condition; the current sensor includes a first current sensor, the range of the first current sensor being a first range; determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit includes: determining whether the current of the high-voltage main circuit exceeds the upper limit of the first range; if the current of the high-voltage main circuit does not exceed the upper limit of the first range, determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit and a preset threshold; If the high-voltage main circuit reaches the fuse-breaking condition, then control the fuse to open; The control method further includes: If the current in the high-voltage main circuit exceeds the upper limit of the first range, the moment when the current in the high-voltage main circuit exceeds the upper limit of the first range is taken as the start sampling moment, and the parameter data of the battery pack at the start sampling moment and the parameter data of the battery pack at each sampling moment after the start sampling moment are obtained. For each sampling time, the difference between the battery pack parameter data at that sampling time and the battery pack parameter data at the start of sampling is determined, and the difference value is defined as the difference data of the battery pack parameter data at that sampling time; the battery pack parameter data includes: the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; Based on the differences in the parameter data of the battery pack, it is determined whether the high-voltage main circuit has reached the fuse-breaking condition.

2. The control method according to claim 1, characterized in that, The step of determining whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit and a preset threshold includes: Determine whether the current of the high-voltage main circuit is greater than a first preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the first preset threshold reaches a first preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; Determine whether the current of the high-voltage main circuit is greater than a second preset threshold and whether the time for which the current of the high-voltage main circuit is greater than the second preset threshold reaches a second preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the first preset threshold is less than the second preset threshold, the second preset threshold is less than the upper limit of the first range, and the first preset time is greater than the second preset time.

3. The control method according to claim 1, characterized in that, The parameter data of the battery pack also includes: the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage.

4. The control method according to claim 3, characterized in that, Based on the difference data in the parameter data of the battery pack, it is determined whether the high-voltage main circuit has reached the fuse-breaking condition. include: The parameter data of the battery pack includes the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack. Determine whether the total voltage difference is greater than a third preset threshold and whether the time during which the total voltage difference is greater than the third preset threshold reaches a fourth preset time; If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; and / or; The parameter data of the battery pack includes the minimum single-cell voltage of the battery cells in the battery pack; the difference data of the minimum single-cell voltage of the battery cells in the battery pack includes the single-cell voltage difference of the minimum single-cell voltage. Determine whether the minimum single-cell voltage difference is greater than a fourth preset threshold and whether the time for which the minimum single-cell voltage difference is greater than the fourth preset threshold reaches a fifth preset time. If so, then the high-voltage main circuit is determined to have reached the fuse-breaking condition; Wherein, the third preset threshold is greater than the upper limit of the first range, the fourth preset threshold is greater than the third preset threshold, and the fourth preset time is greater than or equal to the fifth preset time.

5. The control method according to claim 2, characterized in that, The current sensor further includes a second current sensor, the second current sensor having a second range; the upper limit of the second range is less than the upper limit of the first range. The first preset threshold is less than the upper limit of the second range, and the second preset threshold is greater than the upper limit of the second range and less than the upper limit of the first range.

6. A control device for a power battery fuse, characterized in that, The control device is applied to the BMS in the power battery system, which includes: a fuse and a current sensor installed on the high-voltage main circuit of the power battery system; the control device includes: The acquisition module is used to acquire the current of the high-voltage main circuit through the current sensor; The judgment module is used to determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit; the current sensor includes a first current sensor, and the range of the first current sensor is a first range; the judgment module is specifically used to: determine whether the current of the high-voltage main circuit exceeds the upper limit of the first range; if the current of the high-voltage main circuit does not exceed the upper limit of the first range, determine whether the high-voltage main circuit has reached the fuse-breaking condition based on the current of the high-voltage main circuit and a preset threshold. A control module is used to control the fuse to open if the high-voltage main circuit reaches the melting condition; The judgment module is also specifically used for: If the current in the high-voltage main circuit exceeds the upper limit of the first range, the moment when the current in the high-voltage main circuit exceeds the upper limit of the first range is taken as the start sampling moment, and the parameter data of the battery pack at the start sampling moment and the parameter data of the battery pack at each sampling moment after the start sampling moment are obtained. For each sampling time, the difference between the battery pack parameter data at that sampling time and the battery pack parameter data at the start of sampling is determined, and the difference value is defined as the difference data of the battery pack parameter data at that sampling time; the battery pack parameter data includes: the total voltage of the battery pack; the difference data of the total voltage of the battery pack includes the total voltage difference of the battery pack; Based on the differences in the parameter data of the battery pack, it is determined whether the high-voltage main circuit has reached the fuse-breaking condition.

7. A vehicle, characterized in that, include: The device includes a processor, a memory, and a bus. The memory stores machine-readable instructions executable by the processor. When the electronic device is running, the processor communicates with the memory via the bus. The machine-readable instructions are executed by the processor to perform the steps of the control method for a power battery fuse as described in any one of claims 1 to 5.

8. A computer-readable storage medium, characterized in that, The computer-readable storage medium stores a computer program that, when executed by a processor, performs the steps of the control method for the power battery fuse as described in any one of claims 1 to 5.

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