Battery management system, battery pack, and electrical apparatus

Abstract

Provided in the present disclosure are a battery management system, a battery pack, and an electrical apparatus. The battery management system comprises: a plurality of switch assemblies, each switch assembly being connected between a battery and a corresponding load, and said assemblies being used for establishing or severing a connection between the battery and the corresponding load; a sampling circuit, the sampling circuit comprising sampling branch circuits in one-to-one correspondence with the plurality of switch assemblies, and each sampling branch circuit being used for collecting the voltage at a sampling measurement point; a reference voltage module, which is used for providing a first reference voltage to a reference sampling point; and a sampling module, which is used for obtaining the voltage at each sampling measurement point relative to the reference sampling point; wherein when the plurality of switch assemblies further comprises switch assemblies in parallel, the sampling branch circuits comprise a pair of first sampling branch circuits, with one first sampling branch circuit being connected to one end of the switch assemblies in parallel, and the other first sampling branch circuit being connected to the other end of the switch assemblies in parallel.

Description

Battery management system, battery pack and power consumption device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This disclosure claims priority to the Chinese patent application filed with the China Patent Office on November 30, 2023, with application number 202311641752.1 and invention name “Sampling Circuit, Battery Management System, Battery Pack and Electrical Device”, the entire contents of which are incorporated by reference into this disclosure. Technical Field

[0003] The present disclosure relates to the field of power management technology, and in particular to a battery management system, a battery pack, and an electrical device. Background Art

[0004] With the development of new energy technologies, batteries are increasingly used in various electrical devices, such as mobile phones, laptops, electric vehicles, electric airplanes, electric ships, etc.

[0005] During the operation of an electrical device, the power supply provides power to each unit, ensuring normal operation. Multiple relay switches are typically installed in the high-voltage circuits corresponding to the positive and negative poles of the battery. To ensure the reliability of the battery during use, voltage sampling is performed at various detection points in the battery, and corresponding processing is performed based on the sampling results.

[0006] However, the circuit design for voltage sampling in the related art is complex and costly. Summary of the Invention

[0007] The embodiments of the present disclosure provide a battery management system, a battery pack, and an electrical device, which optimize the circuit design of a sampling circuit and improve the reliability of battery operation.

[0008] In a first aspect, an embodiment of the present disclosure provides a battery management system, the battery management system comprising:

[0009] a plurality of switch assemblies, each switch assembly being connected between the battery and a corresponding load, and being used to connect or disconnect the battery and the corresponding load;

[0010] The sampling circuit includes sampling branches corresponding to the plurality of switch components, each sampling branch being used to collect the voltage at a sampling detection point; wherein the first end of each sampling branch is connected to the corresponding switch component, and the connection point is the sampling detection point; the second end of each sampling branch is connected to the reference voltage module, and the connection point is the reference sampling point; and the third end of each sampling branch is connected to the sampling module;

[0011] A reference voltage module, configured to provide a first reference voltage for a reference sampling point;

[0012] A sampling module is used to obtain the voltage of each sampling detection point relative to the reference sampling point;

[0013] When the multiple switch components further include a parallel switch component, the sampling branch includes two first sampling branches, one of which is connected to one end of the parallel switch component, and the other is connected to the other end of the parallel switch component.

[0014] By configuring a reference voltage module to provide a first reference voltage for a reference sampling point, the first sampling branch can be used to sample the voltage at the sampling detection point relative to the reference sampling point. The sampling module can determine the voltage of each sampling detection point relative to the reference sampling point, thereby enabling voltage sampling at sampling detection points with different voltages. Furthermore, when there are multiple sampling detection points, by sharing the same reference sampling point, the potential difference between any two sampling detection points relative to the reference sampling point can be calculated, thereby enabling circuit detection between the sampling detection points. Furthermore, when at least two switch components are connected in parallel, these at least one switch component can reuse the same set of first sampling branches, thereby simplifying circuit design and reducing circuit costs.

[0015] In one possible implementation of the first aspect, the sampling module is connected to a high-voltage ground. This connection eliminates the need to consider insulation withstand voltage issues, making the selection of switch components with relatively flexible withstand voltage requirements. Furthermore, the sampling circuit resides in a high-voltage region and is no longer connected to a low-voltage region, which improves interference resistance and eliminates the need for isolation components, thereby achieving cost savings.

[0016] In one possible implementation of the first aspect, the reference voltage module includes: a voltage source configured to provide a second reference voltage; and a voltage conversion module connected to the voltage source and configured to convert the second reference voltage of the voltage source to provide corresponding sampling ranges for sampling detection points with different reference voltage requirements. After the voltage source is configured to provide the second reference voltage, the voltage conversion module is used to convert the second reference voltage into a different first reference voltage, so that each sampling detection point can be sampled relative to either the first reference voltage or the second reference voltage, thereby meeting different sampling requirements.

[0017] In one possible implementation of the first aspect, the first reference voltage is smaller than the second reference voltage. By setting the first reference voltage smaller than the second reference voltage, a larger sampling range can be provided for sampling detection points with higher voltages and sampling detection points with lower voltages, respectively, thereby ensuring the accuracy of the sampling results.

[0018] In one possible implementation of the first aspect, a voltage source is connected to the second electrode of the battery, and the second reference voltage is the voltage of the output voltage of the voltage source relative to the second electrode of the battery. By using the second electrode of the battery as a reference ground, the voltage source can provide a first reference voltage relative to the second electrode of the battery for the reference sampling point.

[0019] In one possible implementation of the first aspect, the sampling branch further includes: a second sampling branch connected to the first terminal of the battery and a voltage source; the voltage source is configured to provide a first reference voltage for the second sampling branch; and a sampling module is connected to a third end of the second sampling branch and is configured to obtain a voltage between the first terminal of the battery and the second terminal of the battery. The second sampling branch can be used to sample the voltage between the first terminal of the battery and the second terminal of the battery, thereby directly obtaining the voltage across the battery and implementing voltage sampling of the battery.

[0020] In one possible implementation of the first aspect, the voltage conversion module includes: a first voltage divider connected between a voltage source and a reference sampling point; and a voltage stabilizing unit connected to the reference sampling point. By providing the first voltage divider and the voltage stabilizing unit, a higher second reference voltage can be clamped to output a lower first reference voltage.

[0021] In one possible implementation of the first aspect, the voltage conversion module further includes a second voltage divider connected in parallel with the voltage stabilizing unit. The second voltage divider can achieve a voltage divider function with the first voltage divider, thereby preventing the voltage at the reference sampling point from being too high when an abnormality such as a short circuit occurs in the voltage stabilizing unit.

[0022] In one possible implementation of the first aspect, the sampling branch includes a first sampling unit and a second sampling unit, the first sampling unit and the second sampling unit being connected in series. The first sampling unit and the second sampling unit divide a voltage at a sampling detection point so that a voltage across the second sampling unit falls within a sampling range of the sampling module.

[0023] In one possible implementation of the first aspect, the sampling branch includes a first sampling point, the sampling module includes a first sampling terminal, the first sampling point is disposed between the first sampling unit and the second sampling unit, and the first sampling point is connected to the first sampling terminal of the sampling module. By employing a conventional sampling method in which the first sampling terminal of the sampling module is connected to the first sampling point of the sampling branch, a voltage midway between the first sampling unit and the second sampling unit can be directly sampled. The voltage at the sampling detection point relative to a reference sampling point can be determined by combining a voltage divider ratio between the first sampling unit and the second sampling unit.

[0024] In one possible implementation of the first aspect, the sampling branch includes a second sampling point, the sampling module includes a second sampling terminal, the second sampling point is disposed at both ends of the second sampling unit, and the second sampling point is connected to the second sampling terminal of the sampling module. By providing a differential sampling method in which the second sampling terminal of the sampling module is connected to the second sampling point of the sampling branch, the voltage at both ends of the second sampling unit can be directly sampled. The voltage at the sampling detection point relative to a reference sampling point can be determined by combining the voltage division ratio between the first sampling unit and the second sampling unit.

[0025] In a possible implementation of the first aspect, the second sampling terminal of the sampling module is a differential sampling terminal, and the voltages at both ends of the second sampling unit can be directly acquired through differential sampling.

[0026] In one possible implementation of the first aspect, the sampling branch further includes a sampling control switch connected between the first sampling unit and the second sampling unit; the sampling control switch is configured to turn the sampling branch on or off. The sampling control switch can disconnect the sampling branch when voltage sampling is not required, thereby saving resources.

[0027] In one possible implementation of the first aspect, the multiple switch assemblies include at least one first switch assembly and / or at least one second switch assembly, and the sampling branch includes: a first-pole sampling branch corresponding to the first switch assembly, wherein the sampling detection point corresponding to the first-pole sampling branch is connected to the first pole of the battery via the first switch assembly; and a second-pole sampling branch corresponding to the second switch assembly, wherein the sampling detection point corresponding to the second-pole sampling branch is connected to the second pole of the battery via the second switch assembly. Voltage sampling can be performed at a positive voltage sampling detection point and a negative voltage sampling detection point, respectively, through the first-pole sampling branch and the second-pole sampling branch, and a sampled voltage at each sampling detection point can be obtained, thereby implementing voltage sampling of the high-voltage circuit.

[0028] In one possible implementation of the first aspect, the first switch assembly includes any one of a main positive switch, a pre-charge switch, a main positive DC charging switch, and a main positive AC charging switch, and the second switch assembly includes any one of a main negative switch and a main negative charging switch. By sampling voltage at each sampling detection point, it is also possible to detect whether the switches have a sticking fault or other problems based on the sampling results, thereby implementing status diagnosis of the switch assembly.

[0029] In a second aspect, an embodiment of the present disclosure provides a battery pack, comprising a battery and a battery management system as in any one of the embodiments of the first aspect.

[0030] In a third aspect, an embodiment of the present disclosure provides an electrical device comprising a battery pack according to any one of the embodiments of the second aspect.

[0031] Compared with related technologies, the battery management system, battery pack, and power-consuming device provided by the embodiments of the present disclosure, by setting a reference voltage module to provide a first reference voltage for a reference sampling point, can use a first sampling branch to sample the voltage of a sampling detection point relative to the reference sampling point. The sampling module can determine the voltage of each sampling detection point relative to the reference sampling point, thereby realizing voltage sampling of sampling detection points with different voltages. Moreover, when there are multiple sampling detection points, by sharing the same reference sampling point, the potential difference between any two sampling detection points relative to the reference sampling point can be calculated, thereby realizing circuit detection between the sampling detection points. In addition, when at least two switch components are connected in parallel, the at least one switch component can also reuse the same set of first sampling branches, thereby simplifying circuit design and reducing circuit cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions of the embodiments of the present disclosure, the following briefly introduces the drawings required for use in the embodiments of the present disclosure. Obviously, the drawings described below are only some embodiments of the present disclosure. For ordinary technicians in this field, other drawings can be obtained based on these drawings without any creative work.

[0033] FIG1 is a schematic diagram of a module structure of a sampling circuit provided in an embodiment of the present disclosure;

[0034] FIG2 is a schematic diagram of a module structure of a sampling circuit provided in another embodiment of the present disclosure;

[0035] FIG3 is a schematic diagram of the module structure of a sampling circuit provided in yet another embodiment of the present disclosure;

[0036] FIG4 is a schematic diagram of the module structure of a sampling circuit provided in yet another embodiment of the present disclosure;

[0037] FIG5 is a schematic diagram of the module structure of a sampling circuit provided in yet another embodiment of the present disclosure;

[0038] FIG6 is a schematic diagram of the module structure of a sampling circuit provided in yet another embodiment of the present disclosure;

[0039] FIG7 is a schematic diagram of the circuit structure of a sampling circuit provided in an embodiment of the present disclosure;

[0040] FIG8 is a schematic diagram of a circuit structure of a conventional sampling method provided in an embodiment of the present disclosure;

[0041] FIG9 is a schematic diagram of a circuit structure of a differential sampling method provided in an embodiment of the present disclosure.

[0042] In the accompanying drawings: 10, reference voltage module; 20, first sampling branch; 30, sampling module; 40, battery; 50, second sampling branch; 11, voltage source; 12, voltage conversion module; 121, first voltage divider unit; 122, voltage stabilizing unit; 123, second voltage divider unit; 21, first pole sampling branch; 22, second pole sampling branch; 23, first sampling unit; 24, second sampling unit; 25, sampling control switch; Rs, reference sampling point; Sd, sampling detection point; GND-R, reference ground; Ps, first sampling point; Ns, second sampling point; 61, first switch component; 62, second switch component; K1, main negative switch; K2, main positive switch; K3, pre-charging switch; K4, main positive DC charging switch; K5, main negative charging switch; K6, main positive AC charging switch. DETAILED DESCRIPTION

[0043] The features and exemplary embodiments of various aspects of the present disclosure will be described in detail below. In order to make the purposes, technical solutions and advantages of the present disclosure clearer, the present disclosure will be further described in detail below in conjunction with the accompanying drawings and specific embodiments. It should be understood that the specific embodiments described herein are only intended to explain the present disclosure, rather than to limit the present disclosure. For those skilled in the art, the present disclosure can be implemented without the need for some of these specific details. The following description of the embodiments is merely to provide a better understanding of the present disclosure by illustrating examples of the present disclosure.

[0044] It should be noted that, in this document, relational terms such as first and second, etc., are used only to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any actual relationship or order between these entities or operations. Moreover, the terms "comprises," "comprising," or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article, or device comprising a series of elements includes not only those elements, but also other elements not explicitly listed, or elements inherent to such process, method, article, or device. In the absence of further limitations, the elements defined by the phrase "comprising..." do not exclude the presence of other identical elements in the process, method, article, or device comprising the elements.

[0045] It should be noted that, in the absence of conflict, the embodiments and features in the embodiments of the present disclosure can be combined with each other. The embodiments will be described in detail below with reference to the accompanying drawings.

[0046] With the development of new energy technologies, batteries are increasingly used in various electrical devices, such as mobile phones, laptops, electric vehicles, electric airplanes, electric ships, etc.

[0047] During the operation of an electrical device, the power supply can supply power to each electrical unit to ensure normal operation. The high-voltage circuits corresponding to the first and second poles of the battery are typically equipped with multiple relay switches. To ensure the reliability of the battery during use, voltage sampling is required at various detection points in the battery, and corresponding processing is performed based on the sampling results.

[0048] However, the circuit architecture for voltage sampling in related technologies has certain defects.

[0049] In order to solve the above technical problems, the embodiments of the present disclosure provide a sampling circuit, a battery management system, a battery pack, and an electric device. The sampling circuit provided by the embodiments of the present disclosure is first introduced below.

[0050] According to some embodiments of the present disclosure, referring to FIG1 , the present disclosure provides a sampling circuit comprising a reference voltage module 10 , a first sampling branch 20 , and a sampling module 30 .

[0051] The reference voltage module 10 is connected to the reference sampling point Rs. The reference voltage module 10 can provide a first reference voltage for the reference sampling point Rs, so that the voltage of the reference sampling point Rs relative to the reference ground GND-R is the first reference voltage.

[0052] Taking the example of the voltage source 11 maintaining the first reference voltage at 2.5V, if the voltage of the reference ground GND-R is 0V, the voltage source 11 can make the voltage at the reference sampling point Rs be 2.5V; if the voltage of the reference ground GND-R is 10V relative to the ground, the voltage source 11 can make the voltage at the reference sampling point Rs be 12.5V.

[0053] The first sampling branch 20 can be connected between the corresponding sampling detection point Sd and the reference sampling point Rs in the battery 40. The first sampling branch 20 can sample the voltage of the sampling detection point Sd.

[0054] The sampling terminal of the sampling module 30 can be connected to the first sampling branch 20. The sampling module 30 can determine the voltage of the sampling detection point Sd corresponding to the first sampling branch 20 relative to the reference sampling point Rs based on the sampling signal received from the first sampling branch 20 by the sampling terminal.

[0055] It is understood that the sampling module 30 has a corresponding sampling range, and the voltage of the sampled signal it can acquire should be within this sampling range. When the sampling module 30 uses the reference ground GND-R as a zero voltage reference, the reference voltage module 10 provides a first reference voltage based on the reference ground GND-R to the reference ground GND-R as the bias voltage of the sampling module 30. Therefore, the first reference voltage should be within the sampling range of the sampling module 30, so that the sampled signal acquired by the sampling module 30 does not exceed the sampling range of the sampling module 30.

[0056] Among the plurality of sampling detection points Sd, the potential differences between some of the sampling detection points Sd and the reference ground GND-R are positive, and the potential differences between the other sampling detection points Sd and the reference ground GND-R are negative.

[0057] In the related art, when the negative electrode of the battery 40 is typically used as the reference ground GND-R and the sampling reference of the sampling module 30, the sampling module 30 can normally sample the sampling points Sd where the voltage is higher than the reference ground GND-R, obtaining the voltage of these sampling points Sd relative to the reference ground GND-R. However, the sampling module 30 cannot normally sample the sampling points Sd where the voltage is lower than the reference ground GND-R. In other words, because the sampling port of the sampling chip in the related art can only sample positive voltage, it cannot sample the sampling points Sd where the voltage is lower than the voltage of the negative electrode of the battery 40. For example, as shown in Figure 2, the reference voltage module 10 can be connected to the second electrode of the battery 40, using the second electrode of the battery 40 as the reference ground GND-R. In this case, voltage sampling cannot be performed at the sampling points Sd outside the main negative relay, where the voltage may be lower than the second electrode of the battery 40, thereby failing to meet the voltage sampling requirements of the battery 40.

[0058] In the embodiment of the present disclosure, when the reference ground GND-R can select the second pole of the battery 40, the reference ground can also be called a "high-voltage ground". Taking Figure 2 as an example, the sampling module 30 can be connected to the high-voltage ground GND-R. The high-voltage ground GND-R may refer to the reference ground provided by the high-voltage system, for example, the high-voltage system may be a battery system. It should be noted that in this field, the operating voltage of the battery system belongs to Class B, for example, the maximum operating voltage is between 60V and 1500V, and therefore it is defined as a high-voltage system. At this time, the reference ground provided by the second pole of the battery 40 (i.e., the negative pole of the battery 40) can generally be called the high-voltage ground GND-R.

[0059] It should also be noted that the sampling module 30 is connected to the high-voltage ground GND-R. In this case, there is no need to consider the insulation withstand voltage issue, and the voltage withstand selection of the switching device is relatively relaxed. Moreover, the sampling circuits are all in the high-voltage area and are not connected to the low voltage, so there is no common-mode interference, which improves the anti-interference performance and eliminates the need for isolation devices, which can save costs. It should be noted that Figure 2 is used as an example to describe the connection of the sampling module 30 to the high-voltage ground GND-R, but it is not limited to this. The sampling modules 30 in other figures are also connected to the high-voltage ground GND-R.

[0060] In the above embodiment, referring to FIG. 3 , multiple first sampling branches 20 corresponding to the multiple sampling detection points Sd can be provided. Each first sampling branch 20 is connected between the corresponding sampling detection point Sd and the reference sampling point Rs. The sampling module 30 has multiple sampling terminals connected to the multiple first sampling branches 20. The sampling module 30 can obtain the voltage of each corresponding sampling detection point Sd relative to the reference sampling point Rs through each sampling terminal. By combining this with the first reference voltage between the reference sampling point Rs and the reference ground GND-R, the sampling module 30 can sample the voltages of the multiple sampling detection points Sd relative to the reference ground GND-R.

[0061] Because a first reference voltage is maintained between the reference sampling point Rs and the reference ground GND-R, the sampling module 30 can normally perform voltage sampling at some of the sampling detection points Sd where the voltage is higher than the reference ground GND-R. Furthermore, for some of the sampling detection points Sd where the voltage is lower than the reference ground GND-R, since the first reference voltage is higher than the voltage of these sampling detection points Sd, the sampling module 30 can obtain the potential difference between the reference sampling point Rs and these sampling detection points Sd by sampling positive voltage. Furthermore, the voltage of these sampling detection points Sd relative to the reference ground GND-R is determined based on the first reference voltage between the reference sampling point Rs and the reference ground GND-R, thereby achieving a negative pressure sampling function.

[0062] After obtaining the potential difference of each sampling detection point Sd relative to the reference sampling point Rs, the potential difference between any two sampling detection points Sd can be calculated based on the potential differences of the two sampling detection points Sd relative to the reference sampling point Rs.

[0063] In this embodiment, by configuring the reference voltage module 10 to provide a first reference voltage for the reference sampling point Rs, the first sampling branch 20 can be used to sample the voltage at the sampling detection point Sd relative to the reference sampling point Rs. The sampling module 30 can determine the voltage of each sampling detection point Sd relative to the reference sampling point Rs, thereby enabling voltage sampling at sampling detection points Sd of different voltages. Furthermore, when multiple sampling detection points Sd exist, by sharing the same reference sampling point Rs, the potential difference between any two sampling detection points Rd relative to the reference sampling point Rs can be calculated, thereby enabling circuit detection between the sampling detection points Rd.

[0064] According to some embodiments of the present disclosure, referring to FIG. 4 , the reference voltage module 10 may include a voltage source 11 and a voltage conversion module 12 .

[0065] The voltage source 11 can provide a second reference voltage. The voltage conversion module 12 can be connected to the voltage source 11 and convert the second reference voltage output by the voltage source 11 into a first reference voltage.

[0066] The voltage conversion module 12 may be connected between the voltage source 11 and the reference sampling point Rs. The voltage conversion module 12 may receive the second reference voltage provided by the voltage source 11 and perform voltage conversion on the second reference voltage to obtain the first reference voltage.

[0067] The second reference voltage and the first reference voltage can be set based on the sampling range of the sampling module 30. For example, the second reference voltage can be set to the maximum range voltage of the sampling module 30. In this case, the voltage conversion module 12 can step down the second reference voltage to obtain a first reference voltage lower than the second reference voltage. When using the sampling module 30 for voltage sampling, the resistance values ​​of the respective voltage divider resistors in the first sampling branch 20 can be appropriately set so that when the sampling module 30 samples the voltage at the sampling detection point Sd, where the voltage relative to the reference ground GND-R is positive, the voltage range of the sampled signal collected is between the first reference voltage and the maximum range voltage; and when sampling the voltage at the sampling detection point Sd, where the voltage relative to the reference ground GND-R is negative, the voltage range of the sampled signal collected is between the first reference voltage and the minimum range voltage. In other words, by setting the voltage at the reference sampling point Rs as the first reference voltage, the sampling module 30 can sample the voltage at both the positive and negative sampling detection points Sd.

[0068] After setting the voltage source 11 to provide the second reference voltage, the voltage conversion module 12 is used to convert the second reference voltage into the first reference voltage, so that each sampling detection point can be sampled relative to the first reference voltage or the second reference voltage, thereby providing corresponding sampling ranges for sampling detection points with different reference voltage requirements to meet different sampling requirements.

[0069] According to some embodiments of the present disclosure, the first reference voltage may be lower than the second reference voltage. That is, the voltage conversion module 12 performs a voltage reduction function, converting the higher second reference voltage into the lower first reference voltage.

[0070] In some examples, the first reference voltage can be half the second reference voltage. For example, when the second reference voltage is 5V, it means that the potential difference between the output voltage of the voltage source 11 and the reference ground GND-R is 5V. In this case, the first reference voltage can be set to half the second reference voltage, that is, 2.5V, which means that the potential difference between the reference sampling point Rs and the reference ground GND-R is 2.5V.

[0071] Taking the maximum sampling range of the sampling module 30 as an example, if the voltage at a certain sampling detection point Sd is higher than the reference ground GND-R, the corresponding first sampling branch 20 can be used to sample and divide the voltage between the sampling detection point Sd and the reference sampling point Rs. By adjusting the resistance values ​​of the corresponding resistors in the first sampling branch 20, the divided voltage output by the sampling end of the first sampling branch 20 can be ensured to not exceed the maximum sampling range of the sampling module 30. Since the sampling module 30 is based on the reference ground GND-R, the divided voltage output by the first sampling branch 20 should be at least higher than the voltage of the reference sampling point Rs relative to the reference ground GND-R. In other words, the voltage output by the sampling end of the first sampling branch 20 is between 2.5V and 5V.

[0072] A similar approach can be employed when the voltage at a sampling detection point Sd is lower than the reference ground GND-R. The first sampling branch 20 can sample and divide the voltage between the reference sampling point Rs and the sampling detection point Sd. It will be appreciated that the divided voltage output by the first sampling branch 20 is a positive voltage, which is lower than the voltage at the reference sampling point Rs relative to the reference ground GND-R. In other words, the voltage output by the sampling terminal of the first sampling branch 20 is between 0V and 2.5V.

[0073] The sampling detection point Sd having a voltage higher than the reference ground GND-R is referred to as the positive voltage sampling detection point Sd, while the sampling detection point Sd having a voltage lower than the reference ground GND-R is referred to as the negative voltage sampling detection point Sd. The sampling module 30 can perform voltage sampling at both the positive voltage sampling detection point Sd and the negative voltage sampling detection point Sd via the first sampling branch 20 and calculate the voltage at the sampling detection point Sd relative to the reference sampling point Rs.

[0074] According to some embodiments of the present disclosure, please continue to refer to Figure 4. The above-mentioned reference ground GND-R can be selected as the second pole of the battery 40, the voltage source 11 can be connected to the second pole of the battery 40, and the second reference voltage provided by the voltage source 11 is the voltage difference between the output voltage of the voltage source 11 and the second pole of the battery 40.

[0075] In this embodiment, by using the second terminal of the battery 40 as the reference ground GND-R, the output voltage of the voltage source 11 can be set to a second reference voltage relative to the voltage of the second terminal of the battery 40. The voltage conversion module 12 can convert this second reference voltage into a first reference voltage, so that the voltage at the reference sampling point Rs relative to the second terminal of the battery 40 is the first reference voltage.

[0076] According to some embodiments of the present disclosure, referring to FIG. 5 , the sampling circuit may further include a second sampling branch 50 .

[0077] The second sampling branch 50 can be connected to the first electrode of the battery 40 and the voltage source 11. The voltage source 11 can provide the second sampling branch 50 with a first reference voltage as a bias voltage.

[0078] The second sampling branch 50 can sample and divide the voltage of the first electrode of the battery 40 and use the second reference voltage output by the voltage source 11 as a bias voltage so that the sampling signal output by the second sampling branch 50 meets the sampling range of the sampling module 30 .

[0079] One of the sampling terminals of the sampling module 30 can be connected to the sampling terminal of the second sampling branch 50 to obtain the divided sampling signal output by the second sampling branch 50. Based on this sampling signal, the sampling module 30 can calculate the voltage between the first terminal of the battery 40 and the reference ground GND-R. Since the reference ground GND-R is the second terminal of the battery 40, the voltage calculated by the sampling module 30 is the voltage between the two terminals of the battery 40.

[0080] Referring to FIG. 6 , the plurality of sampling detection points Sd may include a first sampling point Ps and a second sampling point Ns.

[0081] The first sampling point Ps may be a sampling detection point Sd connected to the first terminal of the battery 40 through the first switch component 61 , and the second sampling point Ns may be a sampling detection point Sd connected to the second terminal of the battery 40 through the second switch component 62 .

[0082] Taking a first sampling point Ps among the multiple sampling detection points Sd as an example, this first sampling point Ps is connected to the first electrode of the battery 40 via a first switch assembly 61. When the first switch assembly 61 is normally on, the voltage at the first sampling point Ps is consistent with the voltage at the first electrode of the battery 40. However, when the first switch assembly 61 is off, the voltage at the first sampling point Ps differs from the voltage at the first electrode of the battery 40. Therefore, after the first switch assembly 61 is turned off, the sampling module 30 can obtain the voltage between the first electrode of the battery 40 and the reference ground GND-R, that is, the second electrode of the battery 40. The first sampling branch 20 corresponding to the first sampling point Ps and the sampling module 30 then perform voltage sampling on the first sampling point Ps. The sampling result generated by the sampling module 30 is the voltage of the first sampling point Ps relative to the reference sampling point Rs. Combined with the first reference voltage between the reference sampling point Rs and the reference ground GND-R, the voltage of the first sampling point Ps relative to the reference ground GND-R can be determined. By comparing the voltage between the first and second electrodes of the battery 40 and the voltage of the first sampling point Ps relative to the second electrode of the battery 40 , it can be determined whether the first switch component 61 has a fault such as adhesion after being disconnected.

[0083] As an optional embodiment, the aforementioned method for detecting sticking of the first switch assembly 61 may be to determine whether the difference between the voltage at the first electrode of the battery 40 relative to the reference ground GND-R and the voltage at the first sampling point Ps relative to the reference ground GND-R is less than a preset voltage threshold. If the difference between the sampled voltages at the two sampling points is less than the preset voltage threshold, it can be determined that the first switch assembly 61 is stuck and has failed to disconnect normally. If the difference between the sampled voltages at the two sampling points is greater than the preset voltage threshold, it can be determined that the first switch assembly 61 is disconnected normally.

[0084] Taking a second sampling point Ns among the multiple sampling detection points Sd as an example, after the sampling module 30 determines the voltage of the second sampling point Ns relative to the reference sampling point Rs based on the sampling signal output by the first sampling branch 20, the potential difference between any first sampling point Ps and the second sampling point Ns can be determined as the difference between the voltage of the first sampling point Ps relative to the reference sampling point Rs and the voltage of the second sampling point Ns relative to the reference sampling point Rs. In other words, based on the voltage of a second sampling point Ns relative to the reference sampling point Rs, the voltage of any first sampling point Ps relative to the second sampling point Ns can be obtained. This allows any second sampling point Ns to serve as a reference point, achieving voltage sampling at multiple reference points.

[0085] According to some embodiments of the present disclosure, please continue to refer to FIG. 6 . The first sampling branch may include a first-pole sampling branch 21 and / or a second-pole sampling branch 22 .

[0086] The sampling detection point corresponding to the first-pole sampling branch 21 is the first sampling point Ps, and the sampling detection point corresponding to the second-pole sampling branch 22 is the second sampling point Ns. The first sampling point Ps can be connected to the first pole of the battery 40 via the first switch component 61, and the second sampling point Ns can be connected to the second pole of the battery 40 via the second switch component 62.

[0087] When the plurality of sampling detection points Sd include the first sampling point Ps, a first sampling branch 21 corresponding to the first sampling point Ps may be provided. The first sampling branch 21 may sample the voltage of the first sampling point Ps relative to the reference sampling point Rs.

[0088] Similarly, when the plurality of sampling detection points Sd include the second sampling point Ns, a second sampling branch 22 corresponding to the second sampling point Ns can be set, and the second sampling branch 22 can sample the voltage of the second sampling point Ns relative to the reference sampling point Rs.

[0089] When the multiple sampling detection points include a first sampling point Ps and a second sampling point Ns, corresponding first sampling branches 21 and second sampling branches 22 can be provided to respectively implement voltage sampling of the first sampling point Ps relative to the reference sampling point Rs and voltage sampling of the second sampling point Ns relative to the reference sampling point Rs. The first sampling branch 21 and the second sampling branch 22 can be used to perform voltage sampling at the positive voltage sampling detection point and the negative voltage sampling detection point, respectively, and the sampled voltages at each sampling detection point Sd can be obtained, thereby implementing voltage sampling of the high-voltage circuit.

[0090] 7 , according to some embodiments of the present disclosure, the voltage conversion module 12 may include a first voltage dividing unit 121 and a voltage stabilizing unit 122 .

[0091] The first voltage dividing unit 121 is connected between the voltage source 11 and the reference sampling point Rs. The voltage stabilizing unit 122 is connected to the reference sampling point Rs. The breakdown voltage of the voltage stabilizing unit 122 is the first reference voltage.

[0092] The second reference voltage output by the voltage source 11 is still greater than the second reference voltage after being divided by the first voltage divider 121 . At this time, the voltage stabilizing unit 122 can stabilize the voltage and limit the voltage divided by the first voltage divider 121 to the first reference voltage.

[0093] The first voltage divider 121 can play a voltage divider protection role to prevent the voltage source 11 from being directly connected to the voltage stabilizing unit 122. At this time, the voltage across the first voltage divider 121 is the difference between the second reference voltage and the first reference voltage.

[0094] According to some embodiments of the present disclosure, the voltage conversion module 12 may further include a second voltage dividing unit 123 connected in parallel with the voltage stabilizing unit 122 .

[0095] The first voltage divider unit 121 and the second voltage divider unit 123 can form a voltage divider circuit. When the voltage stabilizing unit 122 is short-circuited, by properly setting the resistance values ​​of the first voltage divider unit 121 and the second voltage divider unit 123, the voltage divided by the second voltage divider unit 123 can be made the first reference voltage. At this time, the voltage between the reference sampling point Rs and the reference ground GND-R can still maintain the first reference voltage.

[0096] In some examples, the first voltage dividing unit 121 and the second voltage dividing unit 123 may be resistors, and the voltage stabilizing unit 122 may be a voltage stabilizing diode.

[0097] In another optional embodiment, the above-mentioned voltage conversion module 12 may also include but is not limited to a DC-DC (Direct Current-Direct Current) conversion module, an LDO (low dropout regulator) or other devices or chips that can convert the second reference voltage into the first reference voltage.

[0098] According to some embodiments of the present disclosure, referring to FIG. 7 , the first sampling branch 20 may include a first sampling unit 23 and a second sampling unit 24 .

[0099] The first sampling unit 23 and the second sampling unit 24 are connected in series.

[0100] The first sampling unit 23 and the second sampling unit 24 can each be composed of a resistor. The number and resistance values ​​of the resistors in the first sampling unit 23 and the second sampling unit 24 can be set based on the normal voltage range of the sampling detection point Sd connected to the first sampling branch 20. For example, when the voltage across the battery 40 is relatively high, if the normal voltage range of the sampling detection point Sd includes a relatively high voltage, the first sampling unit 23 can be configured with a resistor of a relatively high resistance, and the second sampling unit 24 can be configured with a resistor of a relatively low resistance. This ensures that after the first sampling unit 23 and the second sampling unit 24 divide the voltage at the sampling detection point Sd, the voltage difference across the second sampling unit 24 will not be too large to exceed the detection range of the sampling module 30, nor too small to affect the accuracy of the sampling result.

[0101] According to some embodiments of the present disclosure, referring to FIG. 8 , the sampling module 30 may include a first sampling terminal S1 , and the first sampling branch 20 may include a first sampling point disposed between the first sampling unit 23 and the second sampling unit 24 .

[0102] The first sampling point of the first sampling branch 20 may be connected to the first sampling terminal S1 of the sampling module 30 , and the sampling module 30 may obtain the voltage of the first sampling point through the first sampling terminal S1 .

[0103] After acquiring the voltage of the first sampling point through the first sampling point, the sampling module 30 can determine the voltage difference between the two ends of the first sampling branch 20 according to the equivalent resistance values ​​of the first sampling unit 23 and the second sampling unit 24 .

[0104] According to some embodiments of the present disclosure, referring to FIG. 9 , the sampling module 30 may include a second sampling terminal S2 , and the first sampling branch 20 may include a second sampling point disposed on both sides of the second sampling unit 24 , that is, the second sampling point includes at least two sampling points on both sides of the second sampling unit 24 .

[0105] The second sampling point of the first sampling branch 20 can be connected to the second sampling terminal S2 of the sampling module 30. The sampling module 30 can obtain the voltage of the second sampling point through the second sampling terminal S2. When there are two second sampling points, there are also two second sampling terminals S2 of the sampling module 30.

[0106] The sampling module 30 can directly sample the voltage across the second sampling unit 24 through the second sampling terminal S2. After determining the voltage across the second sampling unit 24, the voltage difference across the first sampling branch 20 can be calculated based on the equivalent resistance of the first sampling unit 23 and the second sampling unit 24.

[0107] According to some embodiments of the present disclosure, the second sampling terminal S2 of the sampling module 30 may be a differential sampling terminal, that is, the second sampling terminal S2 may perform differential sampling on both ends of the second sampling unit 24 to obtain a voltage difference between both ends of the second sampling unit 24 .

[0108] The sampling module 30 may be a sampling chip, and the sampling mode of the sampling chip may be differential sampling or conventional sampling.

[0109] When the sampling chip uses differential sampling, the sampling terminal corresponding to the first sampling branch 20 is the second sampling terminal S2, and the second sampling terminal S2 includes a positive sampling terminal and a negative sampling terminal. The positive sampling terminal should be connected to the terminal with a higher voltage between the two ends of the second sampling unit 24 in the first sampling branch 20, and the negative sampling terminal should be connected to the terminal with a lower voltage between the two ends of the second sampling unit 24.

[0110] When the first sampling branch 20 is the first polar sampling branch 21, the voltage between the first sampling unit 23 and the second sampling unit 24 is greater than the voltage at the reference sampling point Rs. In this case, the positive sampling terminal of the second sampling terminal S2 should be connected to the center of the first sampling unit 23 and the second sampling unit 24, and the negative sampling terminal should be connected to the other end of the second sampling unit 24.

[0111] Conversely, when the first sampling branch 20 is the second sampling branch 22, the voltage between the first sampling unit 23 and the second sampling unit 24 is less than the voltage at the reference sampling point Rs. In this case, the negative sampling terminal of the second sampling terminal S2 should be connected to the middle of the first sampling unit 23 and the second sampling unit 24, and the positive sampling terminal should be connected to the other end of the second sampling unit 24.

[0112] It should be noted that the sampling chip may include multiple second sampling terminals S2 . When multiple sampling detection points need to be detected in the sampling circuit, each second sampling terminal S2 may be connected to a corresponding first sampling branch 20 .

[0113] According to some embodiments of the present disclosure, referring to FIG. 7 , the first sampling branch 20 may further include a sampling control switch 25 . The sampling control switch 25 may be connected between the first sampling unit 23 and the second sampling unit 24 .

[0114] The sampling control switch 25 can be switched between on and off states to realize on and off of the first sampling branch 20. Moreover, when the sampling control switch 25 is off, the first sampling branch 20 is disconnected, and the sampling module 30 cannot obtain the sampling signal.

[0115] When voltage sampling is required for a certain sampling detection point Sd, the sampling control switch 25 in the first sampling branch 20 corresponding to the sampling detection point Sd can be controlled to be turned on, and when voltage sampling is not required, the sampling control switch 25 can be controlled to be turned off.

[0116] The circuit architecture of the second sampling branch 50 may be the same as or similar to that of the first sampling branch 20 , and will not be described in detail herein.

[0117] According to some embodiments of the present disclosure, the sampling module 30 may be connected to the sampling control switch 25 , and the sampling module 30 may control the sampling control switch 25 to be turned on or off.

[0118] The sampling module may include a sampling chip, which may further include a switch control terminal, which may be connected to a sampling control switch 25 to control the conduction state of the sampling control switch 25. When the sampling function needs to be enabled, the sampling chip may send a conduction signal to the sampling control switch 25, causing the sampling control switch 25 to connect the first sampling unit 23 with the second sampling unit 24.

[0119] According to some embodiments of the present disclosure, the sampling control switch 25 may include but is not limited to one of a transistor, a photoelectric device, and a relay. The sampling control switch 25 may also be other switching devices or switch equipment capable of achieving on-off control.

[0120] According to some embodiments of the present disclosure, please refer to Figure 7. The above-mentioned first switch component 61 may include any one of the main positive switch K2, the pre-charging switch K3, the main positive DC charging switch K4 and the main positive AC charging switch K6, and the second switch component 62 may include any one of the main negative switch K1 and the main negative charging switch K5.

[0121] Taking the main negative switch K1 as an example, the sampling point connected to the second terminal of the battery 40 via the main negative switch K1 is the second sampling point Ns1. The sampling module 30 corresponding to the second sampling point Ns1 can obtain the voltage of the second sampling point Ns1 relative to the reference sampling point Rs. After the other sampling modules 30 obtain the voltage of any first sampling point Ps relative to the reference sampling point Rs, the voltage of any first sampling point Ps relative to the second sampling point Ns1 can be calculated based on the difference between the two voltages, thereby obtaining the voltage of each first sampling point Ps when the second sampling point Ns1 is used as a reference.

[0122] As shown in FIG7 , GPIO1 - GPIO6 are multiple sampling terminals of the sampling module 30 , and each sampling terminal is connected to the corresponding first sampling branch 20 or second sampling branch 50 to perform voltage sampling on each sampling detection point Sd.

[0123] As an optional implementation, taking the first sampling point Ps1 corresponding to the main positive switch K2 as an example, when the first reference voltage is 2.5V, the voltage of the first sampling point Ps1 relative to the reference sampling point Rs is:

[0124] U Ps1 =(U_GPIO2-2.5) / Ra*(Ra+Rb);

[0125] Wherein, U_GPIO2 is the voltage collected by the GPIO2 port of the sampling module 30 , Ra is the equivalent resistance of the second sampling unit 24 in the corresponding first sampling branch 20 , and Rb is the equivalent resistance of the first sampling unit 23 .

[0126] Similarly, the voltage at the second sampling point Ns1 relative to the reference sampling point Rs is:

[0127] U Ns1 =(U_GPIO5-2.5) / Ra*(Ra+Rb);

[0128] Among them, U_GPIO5 is the voltage collected by the GPIO5 port of the sampling module 30.

[0129] The voltage U of the first sampling point Ps1 relative to the reference sampling point Rs is calculated. Ps1 and the voltage U of the second sampling point Ns1 relative to the reference sampling point Rs Ns1 Then, the voltage of the first sampling point Ps1 relative to the second sampling point Ns1 can be calculated as: Ps1-Ns1 =U Ps1 -U Ns1 =(U_GPIO2-U_GPIO5) / Ra*(Ra+Rb);

[0130] From the above analysis, it can be seen that after determining the voltage of any first sampling point relative to the reference sampling point Rs, the voltage of the first sampling point relative to the second sampling point Ns1 can be calculated, thereby realizing voltage sampling with the second sampling point Ns1 as the reference point.

[0131] Similarly, the sampling point connected to the second terminal of the battery 40 via the main negative charging switch K5 can be the second sampling point Ns2. In a manner similar to the above embodiment, the voltage at each first sampling point Ps can be obtained with the second sampling point Ns as a reference. That is, the second terminal of the battery 40, the second sampling point Ns1, and the second sampling point Ns2 can all serve as reference points, and the voltage at each first sampling point Ps relative to the reference point can be obtained.

[0132] Based on the same inventive concept, the present disclosure further provides a battery management system, which includes the sampling circuit of any of the above embodiments. It is understood that the battery management system has the beneficial effects of the sampling circuit provided by the embodiments of the present disclosure. For details, please refer to the detailed description of the sampling circuit in the above embodiments, and this embodiment will not be repeated here.

[0133] According to some embodiments of the present disclosure, the battery management system may include:

[0134] a plurality of switch assemblies, each switch assembly being connected between the battery and a corresponding load, and being used to connect or disconnect the battery and the corresponding load;

[0135] The sampling circuit includes sampling branches corresponding to the plurality of switch components, each sampling branch being used to collect the voltage at a sampling detection point; wherein the first end of each sampling branch is connected to the corresponding switch component, and the connection point is the sampling detection point; the second end of each sampling branch is connected to the reference voltage module, and the connection point is the reference sampling point; and the third end of each sampling branch is connected to the sampling module;

[0136] A reference voltage module, configured to provide a first reference voltage for a reference sampling point;

[0137] A sampling module is used to obtain the voltage of each sampling detection point relative to the reference sampling point;

[0138] When the multiple switch components further include a parallel switch component, the sampling branch includes two first sampling branches, one of which is connected to one end of the parallel switch component, and the other is connected to the other end of the parallel switch component.

[0139] In an embodiment of the present disclosure, by providing a reference voltage module to provide a first reference voltage to a reference sampling point, the first sampling branch can be used to sample the voltage of a sampling detection point relative to the reference sampling point. The sampling module can determine the voltage of each sampling detection point relative to the reference sampling point, thereby enabling voltage sampling at sampling detection points with different voltages. Furthermore, when there are multiple sampling detection points, by sharing the same reference sampling point, the potential difference between any two sampling detection points relative to the reference sampling point can be calculated, thereby enabling circuit detection between the sampling detection points. In addition, when at least two switch components are connected in parallel, these at least one switch component can reuse the same set of first sampling branches, thereby simplifying circuit design and reducing circuit costs.

[0140] In the disclosed embodiments, the same group of first sampling branches may include first sampling branches disposed at both ends of parallel switch components, and the parallel switch components may refer to at least two switch components connected in parallel. For example, using FIG. 7 as an example, the at least two parallel switch components may include a switch component where the main positive switch K2 is located and a switch component where the pre-charge switch K3 is located. One end of each of these two switch components is connected to the first sampling branch 20a, and the other end of each of these two switch components is connected to the first sampling branch 20b, thereby achieving sampling branch reuse.

[0141] It should be noted that, in addition to the corresponding switches, the switch assembly may also include other devices, which is not limited here. For example, for the switch assembly where the pre-charge switch K3 is located, the switch assembly can be regarded as consisting of the pre-charge switch K3 and the pre-charge resistor connected in series.

[0142] It should also be noted that in the disclosed embodiment, the sampling detection point corresponding to the first sampling branch 20a is directly connected to the first terminal of the battery 40, while the sampling detection point corresponding to the first sampling branch 20b is respectively connected to the first terminal of the battery 40 via parallel switch assemblies (for example, including: the switch assembly where the main positive switch K2 is located and the switch assembly where the pre-charge switch K3 is located). After calculating the voltage difference between the two sampling detection points corresponding to the first sampling branch 20a and the first sampling branch 20b, this voltage difference can be compared with a preset voltage threshold to determine whether a fault such as relay sticking exists in the main positive switch K2 or the pre-charge switch K3.

[0143] That is to say, when at least two switch components are connected in parallel, the at least two switch components can reuse the same group of first sampling branches (for example, may include the first sampling branch 20a and the first sampling branch 20b as shown in Figure 7), thereby simplifying the circuit design and reducing the circuit cost by multiplexing the sampling branches.

[0144] According to some embodiments of the present disclosure, the sampling module is connected to a high voltage ground.

[0145] In the embodiment of the present disclosure, the sampling module is connected to the high voltage ground, so that the sampling module no longer needs to consider the problem of insulation withstand voltage, and the voltage withstand selection of the switching device is relatively loose; and the sampling circuit belongs to the high voltage area and is no longer connected to the low voltage, which can also improve the anti-interference performance and eliminate the need to set up isolation devices, thereby achieving the purpose of cost saving.

[0146] According to some embodiments of the present disclosure, the reference voltage module includes: a voltage source, which is used to provide a second reference voltage; a voltage conversion module, which is connected to the voltage source and is used to convert the second reference voltage of the voltage source to provide corresponding sampling ranges for sampling detection points with different reference voltage requirements.

[0147] In the embodiment of the present disclosure, after setting a voltage source to provide a second reference voltage, a voltage conversion module is used to convert the second reference voltage into a different first reference voltage, thereby making it possible to adjust the reference voltage, so that each sampling detection point can be sampled relative to the first reference voltage or the second reference voltage to meet different sampling requirements.

[0148] According to some embodiments of the present disclosure, the first reference voltage is lower than the second reference voltage.

[0149] In the embodiment of the present disclosure, by setting the first reference voltage to be lower than the second reference voltage, a larger sampling range can be provided for the sampling detection point with higher voltage and the sampling detection point with lower voltage, thereby ensuring the accuracy of the sampling results.

[0150] According to some embodiments of the present disclosure, the voltage source is connected to the second pole of the battery, and the second reference voltage is the output voltage of the voltage source relative to the voltage of the second pole of the battery.

[0151] In the embodiment of the present disclosure, by using the second pole of the battery as a reference ground, the voltage source can provide a first reference voltage relative to the second pole of the battery for the reference sampling point.

[0152] According to some embodiments of the present disclosure, the sampling branch further includes: a second sampling branch connected to the first pole of the battery and a voltage source; the voltage source is used to provide a first reference voltage for the second sampling branch; and a sampling module is connected to the third end of the second sampling branch, and is used to obtain the voltage of the first pole of the battery relative to the second pole of the battery.

[0153] In the embodiment of the present disclosure, the voltage of the first pole of the battery relative to the second pole of the battery can be sampled through the second sampling branch, thereby directly obtaining the voltage across the battery and realizing voltage sampling of the battery.

[0154] According to some embodiments of the present disclosure, the voltage conversion module includes: a first voltage dividing unit connected between a voltage source and a reference sampling point; and a voltage stabilizing unit connected to the reference sampling point.

[0155] In the embodiment of the present disclosure, by providing the first voltage dividing unit and the voltage stabilizing unit, the higher second reference voltage can be clamped to output the lower first reference voltage.

[0156] According to some embodiments of the present disclosure, the voltage conversion module further includes a second voltage divider connected in parallel with the voltage stabilizing unit. This allows the second voltage divider to work with the first voltage divider to achieve a voltage divider effect, thereby preventing the voltage at the reference sampling point from being excessively high when an abnormality such as a short circuit occurs in the voltage stabilizing unit.

[0157] According to some embodiments of the present disclosure, a sampling branch includes a first sampling unit and a second sampling unit, which are connected in series. The first sampling unit and the second sampling unit divide the voltage at a sampling detection point so that the voltage across the second sampling unit falls within a sampling range of the sampling module.

[0158] According to some embodiments of the present disclosure, a sampling branch includes a first sampling point, and a sampling module includes a first sampling terminal; the first sampling point is disposed between a first sampling unit and a second sampling unit; and the first sampling point is connected to the first sampling terminal of the sampling module. Thus, by employing a conventional sampling method in which the first sampling terminal of the sampling module is connected to the first sampling point of the sampling branch, it is possible to directly sample the voltage at a point midway between the first sampling unit and the second sampling unit. The voltage at the sampling detection point relative to a reference sampling point can be determined by combining the voltage division ratio of the first sampling unit and the second sampling unit.

[0159] According to some embodiments of the present disclosure, the sampling branch includes a second sampling point, the sampling module includes a second sampling terminal, the second sampling point is disposed at both ends of the second sampling unit, and the second sampling point is connected to the second sampling terminal of the sampling module. Thus, by employing a differential sampling method in which the second sampling terminal of the sampling module is connected to the second sampling point of the sampling branch, the voltage at both ends of the second sampling unit can be directly sampled. The voltage at the sampling detection point relative to a reference sampling point can be determined by combining the voltage division ratio of the first sampling unit and the second sampling unit.

[0160] According to some embodiments of the present disclosure, the second sampling terminal of the sampling module is a differential sampling terminal, so that the voltages at both ends of the second sampling unit are differentially sampled by differential sampling, and the voltages at both ends of the second sampling unit can be directly obtained.

[0161] According to some embodiments of the present disclosure, the sampling branch further includes a sampling control switch connected between the first sampling unit and the second sampling unit. The sampling control switch is configured to switch the sampling branch on and off. This allows the sampling control switch to disconnect the sampling branch when voltage sampling is not required, thereby saving resources.

[0162] According to some embodiments of the present disclosure, the multiple switch assemblies include at least one first switch assembly and / or at least one second switch assembly, and the sampling branch includes: a first-pole sampling branch corresponding to the first switch assembly, wherein the sampling detection point corresponding to the first-pole sampling branch is connected to the first pole of the battery via the first switch assembly; and a second-pole sampling branch corresponding to the second switch assembly, wherein the sampling detection point corresponding to the second-pole sampling branch is connected to the second pole of the battery via the second switch assembly. In this way, voltage sampling can be performed at the positive voltage sampling detection point and the negative voltage sampling detection point respectively through the first-pole sampling branch and the second-pole sampling branch, and the sampled voltage at each sampling detection point can be obtained, thereby achieving voltage sampling of the high-voltage circuit.

[0163] According to some embodiments of the present disclosure, the first switch assembly includes any one of a main positive switch, a pre-charge switch, a main positive DC charging switch, and a main positive AC charging switch, and the second switch assembly includes any one of a main negative switch and a main negative charging switch. By sampling the voltage at each sampling point, it is possible to detect whether the switches have experienced problems such as sticking faults based on the sampling results, thereby achieving status diagnosis of the switch assembly.

[0164] Based on the same inventive concept, the present disclosure further provides a battery pack, which includes a battery and the battery management system of any of the above embodiments. It is understood that the battery pack has the beneficial effects of the battery management system provided by the embodiments of the present disclosure.

[0165] Based on the same inventive concept, the present disclosure further provides an electrical device comprising the battery pack of any of the above embodiments. It is understood that the electrical device has the beneficial effects of the battery pack provided by the embodiments of the present disclosure. For details, please refer to the detailed description of the battery pack in the above embodiments, and this embodiment will not be repeated here.

[0166] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of the present disclosure may be combined with each other.

[0167] The functional blocks shown in the above-described block diagram can be implemented as hardware, software, firmware or a combination thereof. When implemented in hardware, they can be, for example, electronic circuits, application specific integrated circuits (ASICs), appropriate firmware, plug-ins, function cards, etc. When implemented in software, the elements of the present disclosure are programs or code segments that are used to perform the required tasks. The program or code segment can be stored in a machine-readable medium, or transmitted on a transmission medium or a communication link by a first data signal carried in a carrier wave. "Machine-readable medium" can include any medium capable of storing or transmitting information. Examples of machine-readable media include electronic circuits, semiconductor memory devices, ROMs, flash memories, erasable ROMs (EROMs), floppy disks, CD-ROMs, optical disks, hard disks, optical fiber media, radio frequency (RF) links, etc. The code segment can be downloaded via a computer network such as the Internet, an intranet, etc.

[0168] It should be noted that, in this article, the terms "comprises", "includes" or any other variations thereof are intended to cover non-exclusive inclusion, so that a process, method, article or apparatus that includes a series of elements includes not only those elements, but also includes other elements not explicitly listed, or also includes elements that are inherent to such process, method, article or apparatus.

[0169] This article uses specific examples to illustrate the principles and implementation methods of the present disclosure. The above examples are only used to help understand the methods and core ideas of the present disclosure. The above are only preferred implementation methods of the present disclosure. It should be pointed out that due to the limitations of textual expression, there are objectively infinite specific structures. For ordinary technicians in this technical field, without departing from the principles of the present disclosure, they can also make several improvements, modifications or changes, and can also combine the above technical features in an appropriate manner; these improvements, modifications, changes or combinations, or the direct application of the concepts and technical solutions of the present disclosure to other occasions without improvement, should all be regarded as the scope of protection of the present disclosure. Industrial Applicability

[0170] In an embodiment of the present application, by providing a reference voltage module to provide a first reference voltage for a reference sampling point, the first sampling branch can be used to sample the voltage of a sampling detection point relative to the reference sampling point. The sampling module can determine the voltage of each sampling detection point relative to the reference sampling point, thereby enabling voltage sampling of sampling detection points with different voltages. Furthermore, when there are multiple sampling detection points, by sharing the same reference sampling point, the potential difference between any two sampling detection points relative to the reference sampling point can be calculated, thereby enabling circuit detection between the sampling detection points. In addition, when at least two switch components are connected in parallel, the at least one switch component can reuse the same set of first sampling branches, thereby simplifying circuit design and reducing circuit cost.

Claims

1. A battery management system, comprising: A plurality of switch components, each of which is connected between a battery and a corresponding load, and is used to connect or disconnect the battery from the corresponding load; A sampling circuit, wherein the sampling circuit comprises sampling branches corresponding to the plurality of switch components one by one, and each sampling branch is used to collect the voltage of a sampling detection point; wherein the first end of each sampling branch is connected to the corresponding switch component, and the connection point is the sampling detection point; the second end of each sampling branch is connected to a reference voltage module, and the connection point is a reference sampling point; and the third end of each sampling branch is connected to a sampling module; The reference voltage module is used to provide a first reference voltage for the reference sampling point; The sampling module is used to obtain the voltage of each sampling detection point relative to the reference sampling point; Wherein, when the multiple switch components include parallel switch components, the sampling branch includes two first sampling branches, one of the first sampling branches is connected to one end of the parallel switch component, and the other first sampling branch is connected to the other end of the parallel switch component.

2. The battery management system according to claim 1, wherein: The sampling module is connected to a high voltage ground.

3. The battery management system according to claim 1 or 2, wherein: The reference voltage module comprises: A voltage source, the voltage source being used to provide a second reference voltage; The voltage conversion module is connected to the voltage source and is used to convert the second reference voltage of the voltage source to provide corresponding sampling ranges for sampling detection points with different reference voltage requirements.

4. The battery management system according to claim 3, wherein: The voltage source is connected to the second pole of the battery, and the second reference voltage is the voltage of the output voltage of the voltage source relative to the second pole of the battery.

5. The battery management system according to claim 4, wherein: The sampling branch also includes: A second sampling branch is connected to the first electrode of the battery and the voltage source; the voltage source is used to provide a first reference voltage for the second sampling branch; The sampling module is connected to the third end of the second sampling branch, and is used to obtain the voltage of the first pole of the battery relative to the second pole of the battery.

6. The battery management system according to claim 3, wherein: The voltage conversion module comprises: A first voltage dividing unit, wherein the first voltage dividing unit is connected between the voltage source and the reference sampling point; A voltage stabilizing unit is connected to the reference sampling point.

7. The battery management system according to claim 6, wherein: The voltage conversion module further includes a second voltage dividing unit connected in parallel with the voltage stabilizing unit.

8. The battery management system according to any one of claims 1 to 7, wherein: The sampling branch comprises: A first sampling unit and a second sampling unit, wherein the first sampling unit and the second sampling unit are connected in series.

9. The battery management system according to claim 8, wherein: The sampling branch includes a first sampling point, and the sampling module includes a first sampling end; The first sampling point is arranged between the first sampling unit and the second sampling unit; The first sampling point is connected to the first sampling end of the sampling module.

10. The battery management system according to claim 8, wherein: The sampling branch includes a second sampling point, and the sampling module includes a second sampling end; The second sampling points are arranged at two ends of the second sampling unit; The second sampling point is connected to the second sampling end of the sampling module.

11. The battery management system according to claim 10, wherein: The second sampling terminal of the sampling module is a differential sampling terminal.

12. The battery management system according to claim 8, wherein: The sampling branch also includes: A sampling control switch, the sampling control switch is connected between the first sampling unit and the second sampling unit; the sampling control switch is used to turn on or off the sampling branch.

13. The battery management system according to any one of claims 1 to 12, wherein: The plurality of switch components include at least one first switch component and / or at least one second switch component, and the sampling branch includes: A first-pole sampling branch is provided corresponding to the first switch component, and a sampling detection point corresponding to the first-pole sampling branch is connected to the first pole of the battery through the first switch component; A second-pole sampling branch is provided corresponding to the second switch component, and a sampling detection point corresponding to the second-pole sampling branch is connected to the second pole of the battery through the second switch component.

14. The battery management system according to claim 13, wherein: The first switch assembly includes any one of a main positive switch, a pre-charging switch, a main positive DC charging switch, and a main positive AC charging switch, and the second switch assembly includes any one of a main negative switch and a main negative charging switch.

15. A battery pack comprising a battery and the battery management system according to any one of claims 1 to 14.

16. An electrical device comprising the battery pack according to claim 15.

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