Sampling circuit and calibration method therefor, battery management system, and electric device

Abstract

A sampling circuit and a calibration method therefor, a battery management system, and an electric device. The calibration method comprises: acquiring the voltage of a first type sampling point and the voltage of a second type sampling point (S101); on the basis of the voltage of the first type sampling point and the voltage of the second type sampling point, determining a calibration factor corresponding to the first type sampling point (S102); and on the basis of the calibration factor, correcting the voltage of the first type sampling point to obtain the corrected voltage of the first type sampling point (S103).

Description

Sampling circuit and calibration method thereof, battery management system and power consumption device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202311277380.9, filed on September 28, 2023, entitled “Sampling circuit and calibration method thereof, battery management system and power-consuming device,” and the entire contents of that application are incorporated herein by reference. Technical Field

[0003] The present application relates to the field of batteries, and in particular to a sampling circuit and a calibration method thereof, a battery management system, and an electrical device. Background Art

[0004] As environmental pollution becomes increasingly severe, market demand for new energy vehicles continues to expand, and requirements for new energy vehicle technology are becoming increasingly stringent, especially for the safety performance of new energy vehicles. To improve the safety of new energy vehicles, it is necessary to sample some of the devices under test (DUT) in new energy vehicles, such as batteries.

[0005] However, the inventors of the present application have found that as time goes by, the components in the sampling circuit will age, causing the sampling accuracy of some sampling points in the sampling circuit to deteriorate, resulting in low accuracy of the sampling results.

[0006] Summary of the Invention

[0007] The present application provides a sampling circuit and a calibration method thereof, a battery management system, and an electric device, which can solve the problem of poor sampling accuracy of sampling points in a sampling circuit.

[0008] In a first aspect, the present application provides a calibration method for a sampling circuit, the calibration method comprising: obtaining a voltage at a first type of sampling point and a voltage at a second type of sampling point; determining a calibration factor corresponding to the first type of sampling point based on the voltage at the first type of sampling point and the voltage at the second type of sampling point; and correcting the voltage at the first type of sampling point based on the calibration factor to obtain a corrected voltage at the first type of sampling point.

[0009] In the technical solution of the embodiments of the present application, the voltages of the second-type sampling points with higher sampling accuracy are used to calculate the calibration factors corresponding to the first-type sampling points. The voltages of the first-type sampling points are corrected based on the calibration factors to obtain the corrected voltages of the first-type sampling points. This allows the first-type sampling points to have the same or similar sampling accuracy as the second-type sampling points, thus improving the sampling accuracy of the first-type sampling points in the sampling circuit and ensuring a high accuracy of the sampling results.

[0010] According to some embodiments of the present application, optionally, determining a calibration factor corresponding to the first-type sampling point according to the voltage of the first-type sampling point and the voltage of the second-type sampling point includes: determining the calibration factor corresponding to the first-type sampling point according to the voltage of the first-type sampling point at multiple moments and the voltage of the second-type sampling point at multiple moments.

[0011] According to some embodiments of the present application, optionally, determining a calibration factor corresponding to the first-type sampling point based on the voltage of the first-type sampling point and the voltage of the second-type sampling point includes: establishing a relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point at multiple moments in time; and determining the calibration factor corresponding to the first-type sampling point based on the relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point.

[0012] According to some embodiments of the present application, optionally, determining the calibration factor corresponding to the first-type sampling point based on the voltage of the first-type sampling point and the voltage of the second-type sampling point includes: establishing a first relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point based on the voltage of the first-type sampling point obtained at a first moment and the voltage of the second-type sampling point obtained at the first moment; establishing a second relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point based on the voltage of the first-type sampling point obtained at a second moment and the voltage of the second-type sampling point obtained at the second moment; and determining the calibration factor corresponding to the first-type sampling point based on the first relationship and the second relationship.

[0013] According to some embodiments of the present application, optionally, the voltage of the first-type sampling point includes the voltage of the first-type sampling point relative to a first reference potential, and the voltage of the second-type sampling point includes the voltage of the second-type sampling point relative to a second reference potential; and establishing a first relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point based on the voltage of the first-type sampling point obtained at a first moment and the voltage of the second-type sampling point obtained at the first moment includes: establishing the first relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point based on a voltage difference between the first reference potential and the second reference potential, the voltage of the first-type sampling point obtained at the first moment, and the voltage of the second-type sampling point obtained at the first moment.

[0014] According to some embodiments of the present application, optionally, establishing the second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point based on the voltage of the first type of sampling point obtained at the second moment and the voltage of the second type of sampling point obtained at the second moment includes establishing the second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point based on the voltage difference between the first reference potential and the second reference potential, the voltage of the first type of sampling point obtained at the second moment, and the voltage of the second type of sampling point obtained at the second moment.

[0015] According to some embodiments of the present application, optionally, the calibration factor includes a first calibration parameter and a second calibration parameter; and correcting the voltage of the first-type sampling point based on the calibration factor to obtain the corrected voltage of the first-type sampling point includes: calculating the product of the voltage of the first-type sampling point and the first calibration parameter; and calculating the sum of the product and the second calibration parameter to obtain the corrected voltage of the first-type sampling point.

[0016] According to some embodiments of the present application, optionally, the voltage of the first type of sampling point includes the voltage of the first type of sampling point relative to a first reference potential, and the voltage of the second type of sampling point includes the voltage of the second type of sampling point relative to a second reference potential; and calculating the sum of the product and the second calibration parameter to obtain the corrected voltage of the first type of sampling point includes: calculating a voltage difference between the first reference potential and the second reference potential, and the sum of the product and the second calibration parameter to obtain the corrected voltage of the first type of sampling point.

[0017] In a second aspect, the present application provides a sampling circuit, comprising: a first-type sampling branch, the first-type sampling branch being electrically connected to a device under test, the first-type sampling branch being provided with a first-type voltage divider module and a first-type sampling point; a second-type sampling branch, the second-type sampling branch being electrically connected to the device under test, the second-type sampling branch being provided with a second-type voltage divider module, a switch module, and a second-type sampling point; and a sampling processing module, the sampling processing module being electrically connected to the first-type sampling point and the second-type sampling point, respectively, the sampling processing module being configured to correct a voltage of the first-type sampling point based on a calibration factor, the calibration factor being determined based on the voltage of the first-type sampling point and the voltage of the second-type sampling point.

[0018] According to some embodiments of the present application, optionally, the first-type sampling branch is electrically connected to the first reference voltage terminal, and the second-type sampling branch is electrically connected to the second reference voltage terminal; the voltage of the first-type sampling point includes the voltage of the first-type sampling point relative to the first reference voltage terminal, and the voltage of the second-type sampling point includes the voltage of the second-type sampling point relative to the second reference voltage terminal.

[0019] According to some embodiments of the present application, optionally, the first type of sampling branch includes a first sampling branch, a first end of the first sampling branch is electrically connected to the first electrode of the device under test, and a second end of the first sampling branch is electrically connected to the first reference voltage terminal, and the first type of sampling point includes a first sampling point located in the first sampling branch; the second type of sampling branch includes a second sampling branch, a first end of the second sampling branch is electrically connected to the first electrode of the device under test, and a second end of the second sampling branch is electrically connected to the second reference voltage terminal, and the second type of sampling point includes a second sampling point located in the second sampling branch, and the switch module includes a first switch module, and the second sampling point performs sampling when the first switch module is turned on.

[0020] According to some embodiments of the present application, optionally, the first type of sampling branch includes a third sampling branch, a first end of the third sampling branch is electrically connected to the first reference voltage end, and a second end of the third sampling branch is electrically connected to the second electrode of the device under test, and the first type of sampling point includes a third sampling point located in the third sampling branch; the second type of sampling branch includes a fourth sampling branch, a first end of the fourth sampling branch is electrically connected to the second reference voltage end, and a second end of the fourth sampling branch is electrically connected to the second electrode of the device under test, and the second type of sampling point includes a fourth sampling point located in the fourth sampling branch, and the switch module includes a second switch module, and the fourth sampling point performs sampling when the second switch module is turned on.

[0021] According to some embodiments of the present application, optionally, the sampling circuit further includes a third switch module, a first end of the third switch module is electrically connected to the first electrode of the device under test; the first type of sampling branch further includes a fifth sampling branch, a first end of the fifth sampling branch is electrically connected to the second end of the third switch module, and a second end of the fifth sampling branch is electrically connected to the first reference voltage end; the first type of sampling point further includes a fifth sampling point located in the fifth sampling branch.

[0022] According to some embodiments of the present application, optionally, the sampling circuit further includes a fourth switch module, a first end of the fourth switch module is electrically connected to the second electrode of the device under test; the first type of sampling branch further includes a sixth sampling branch, a first end of the sixth sampling branch is electrically connected to the first reference voltage end, and a second end of the sixth sampling branch is electrically connected to the second end of the fourth switch module; and the first type of sampling point further includes a sixth sampling point located in the sixth sampling branch.

[0023] According to some embodiments of the present application, optionally, the voltage of the first reference voltage terminal is greater than 0V and less than the maximum value of the sampling range of the sampling chip.

[0024] According to some embodiments of the present application, optionally, the first sampling branch includes a first voltage divider module, a second voltage divider module and a first sampling point; the first end of the first voltage divider module is electrically connected to the first electrode of the device under test, and the second end of the first voltage divider module is electrically connected to the first sampling point; the first end of the second voltage divider module is electrically connected to the first sampling point, and the second end of the second voltage divider module is electrically connected to the first reference voltage end; the sum of the resistance values ​​of the first voltage divider module and the second voltage divider module has a value range of 25-30 megohms.

[0025] According to some embodiments of the present application, optionally, the sampling circuit also includes a follower; the first input terminal of the follower is electrically connected to the first type of sampling point, the second input terminal of the follower is electrically connected to the output terminal of the follower, the first power input terminal of the follower is electrically connected to the positive power supply voltage signal terminal, the second power input terminal of the follower is electrically connected to the ground terminal, and the output terminal of the follower is electrically connected to the voltage collection terminal of the sampling chip; the potential reference terminal of the sampling chip is electrically connected to the ground terminal.

[0026] In a third aspect, the present application provides a battery management system, which includes the sampling circuit provided in the second aspect.

[0027] In a fourth aspect, the present application provides an electrical device, which includes the battery management system provided in the third aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0029] FIG1 is a flow chart of a calibration method for a sampling circuit according to an embodiment of the present application;

[0030] FIG2 is a circuit connection diagram of a sampling circuit provided in an embodiment of the present application;

[0031] FIG3 is a flow chart of S102 in the calibration method of the sampling circuit provided in an embodiment of the present application;

[0032] FIG4 is another flow chart of a calibration method for a sampling circuit according to an embodiment of the present application;

[0033] FIG5 is a flow chart of S103 in the calibration method of the sampling circuit provided in an embodiment of the present application;

[0034] FIG6 is another circuit connection diagram of the sampling circuit provided in an embodiment of the present application;

[0035] FIG7 is another flowchart of a calibration method for a sampling circuit according to an embodiment of the present application;

[0036] FIG8 is another circuit connection diagram of the sampling circuit provided in an embodiment of the present application;

[0037] FIG9 is another circuit connection diagram of the sampling circuit provided in an embodiment of the present application;

[0038] FIG10 is another circuit connection diagram of the sampling circuit provided in an embodiment of the present application.

[0039] In the accompanying drawings, the drawings are not necessarily drawn to scale. DETAILED DESCRIPTION

[0040] To make the purpose, technical solutions, and advantages of the embodiments of this application more clear, the technical solutions in the embodiments of this application will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of this application. Obviously, the described embodiments are part of the embodiments of this application, not all of the embodiments. Based on the embodiments in this application, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of this application.

[0041] The following embodiments of the technical solution of the present application will be described in detail with reference to the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present application and are therefore only examples and are not intended to limit the scope of protection of the present application.

[0042] It should be noted that, unless otherwise specified, the technical terms or scientific terms used in the embodiments of the present application should have the common meanings understood by technicians in the field to which the embodiments of the present application belong.

[0043] In the description of the embodiments of this application, the technical terms "first," "second," etc. are used for descriptive purposes only and should not be understood to indicate or imply relative importance or implicitly specify the number of the technical features indicated. In the description of the embodiments of this application, the meaning of "plurality" is more than two, unless otherwise specifically defined.

[0044] In the description of the embodiments of this application, unless otherwise expressly specified or limited, technical terms such as "mounted," "connected," "connect," and "fixed" should be interpreted broadly. For example, they may refer to fixed or detachable connections, or integration; mechanical or electrical connections; direct or indirect connections through an intermediate medium; and internal communication between two components or interaction between two components. Those skilled in the art will understand the specific meanings of these terms in the embodiments of this application based on specific circumstances.

[0045] In the description of the embodiments of the present application, unless otherwise expressly specified or limited, a first feature being "above" or "below" a second feature may mean that the first and second features are in direct contact, or that the first and second features are in indirect contact through an intermediate medium. Furthermore, a first feature being "above," "above," and "above" a second feature may mean that the first feature is directly above or obliquely above the second feature, or simply means that the first feature is at a higher level than the second feature. A first feature being "below," "below," and "below" a second feature may mean that the first feature is directly below or obliquely below the second feature, or simply means that the first feature is at a lower level than the second feature.

[0046] In order to improve the safety of new energy vehicles, it is usually necessary to sample some devices to be tested (such as batteries) in new energy vehicles. In the embodiment of the present application, the devices to be tested include, but are not limited to, power batteries. Among them, power batteries include but are not limited to lithium-ion batteries, lithium metal batteries, lead-acid batteries, nickel-ion batteries, nickel-metal hydride batteries, lithium-sulfur batteries, lithium-air batteries or sodium-ion batteries, which are not limited here. In terms of scale, the power battery can be a single cell, a battery module or a battery pack, which are not limited here.

[0047] The inventors have noted that, over time, components in a sampling circuit age, resulting in a decrease in sampling accuracy at some sampling points in the sampling circuit, leading to lower accuracy in the sampling results. In particular, in some sampling branches within the sampling circuit, to protect components and reduce costs, these sampling branches typically employ voltage divider modules (e.g., resistors) with larger resistance and lower accuracy. As the voltage divider modules age over time, the accuracy of these larger resistance, lower accuracy voltage divider modules decreases, leading to a decrease in sampling accuracy at the sampling points in these sampling branches, resulting in lower accuracy in the sampling results.

[0048] To address the above technical problems, the present application provides a sampling circuit and calibration method thereof, a battery management system, and an electrical device. The calibration factors corresponding to first-type sampling points are calculated using the voltages of second-type sampling points with higher sampling accuracy. The voltages of the first-type sampling points are corrected based on the calibration factors to obtain the corrected voltages of the first-type sampling points. This ensures that the first-type sampling points have the same or similar sampling accuracy as the second-type sampling points, thus improving the sampling accuracy of the first-type sampling points in the sampling circuit and ensuring a high degree of accuracy in the sampling results.

[0049] The following first introduces the calibration method of the sampling circuit provided in the embodiment of the present application.

[0050] FIG1 is a flow chart of a calibration method for a sampling circuit according to an embodiment of the present application. As shown in FIG1 , the calibration method for a sampling circuit according to an embodiment of the present application may include steps S101 to S103.

[0051] S101 : Obtain voltages at first-type sampling points and voltages at second-type sampling points.

[0052] The first type of sampling points and the second type of sampling points may be different sampling points in the sampling circuit.

[0053] S102 : Determine a calibration factor corresponding to the first type of sampling point according to the voltage of the first type of sampling point and the voltage of the second type of sampling point.

[0054] In some embodiments, for example, the sampling accuracy of the first type of sampling points and the second type of sampling points can be different. For example, the sampling accuracy of the second type of sampling points can be higher than the sampling accuracy of the first type of sampling points. Since the voltage accuracy of the second type of sampling points is higher, the voltage of the second type of sampling points can be used to calibrate the voltage of the first type of sampling points. For example, in S202, the calibration factor corresponding to the first type of sampling points can be determined based on the voltage of the first type of sampling points and the voltage of the second type of sampling points.

[0055] S103 : Correcting the voltage of the first type of sampling point based on the calibration factor to obtain the corrected voltage of the first type of sampling point.

[0056] After obtaining the calibration factors corresponding to the first type of sampling points, the voltages of the first type of sampling points may be corrected based on the calibration factors corresponding to the first type of sampling points, thereby obtaining the corrected voltages of the first type of sampling points.

[0057] The calibration method for a sampling circuit according to an embodiment of the present application calculates a calibration factor corresponding to a first-type sampling point using the voltage of a second-type sampling point having higher sampling accuracy. The voltage of the first-type sampling point is corrected based on the calibration factor to obtain the corrected voltage of the first-type sampling point. This ensures that the first-type sampling point has the same or similar sampling accuracy as the second-type sampling point, thus improving the sampling accuracy of the first-type sampling point in the sampling circuit and ensuring a high accuracy of the sampling result.

[0058] For ease of understanding, the calibration method of the sampling circuit is described below in conjunction with the circuit structures of the sampling circuits in some application embodiments. It should be noted that the calibration method of the sampling circuit in the embodiments of the present application is not limited to the sampling circuits shown in the following figures.

[0059] FIG2 is a schematic diagram of a circuit connection of a sampling circuit provided in an embodiment of the present application. As shown in FIG1 , in some embodiments, the sampling circuit 10 may include a first-type sampling branch 101 and a second-type sampling branch 102. Both the first-type sampling branch 101 and the second-type sampling branch 102 are electrically connected to the device under test 20. The first-type sampling branch 101 is provided with a first-type voltage divider module FL1 and a first-type sampling point UL1. The second-type sampling branch 102 is provided with a second-type voltage divider module FL2, a switch module K, and a second-type sampling point UL2. The switch module K is provided in the second-type sampling branch 102. When the switch module K is turned on, the second-type sampling point UL2 performs sampling. In the embodiment of the present application, the device under test 20 includes, for example, but is not limited to, a power battery.

[0060] For example, the resistance values ​​of the first-type voltage divider module FL1 and the second-type voltage divider module FL2 can be different. As shown in FIG2 , since the second-type sampling branch 102 includes a switch module K, when the output voltage of the device under test 20 is high, the switch module K can be disconnected to prevent damage to the components in the second-type sampling branch 102 (such as the second-type voltage divider module FL2). Therefore, compared to the first-type sampling branch 101, the second-type sampling branch 102 can use a relatively small resistance and relatively high precision resistor, thereby improving the sampling accuracy of the second-type sampling point UL2.

[0061] As shown in combination with FIG. 1 and FIG. 2 , in S101 , for example, the voltage of the first type of sampling point UL1 and the voltage of the second type of sampling point UL2 may be collected.

[0062] Since the voltage at the second-type sampling point UL2 has a higher accuracy, the voltage at the first-type sampling point UL1 can be corrected using the voltage at the second-type sampling point UL2. For example, in S102, a calibration factor corresponding to the first-type sampling point UL1 can be calculated based on the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2.

[0063] In S103 , after obtaining the calibration factor corresponding to the first type sampling point UL1 , the voltage of the first type sampling point may be corrected based on the calibration factor corresponding to the first type sampling point UL1 , thereby obtaining the corrected voltage of the first type sampling point.

[0064] The calibration method for a sampling circuit according to an embodiment of the present application calculates a calibration factor corresponding to a first-type sampling point using the voltage of a second-type sampling point having higher sampling accuracy. The voltage of the first-type sampling point is corrected based on the calibration factor to obtain the corrected voltage of the first-type sampling point. This ensures that the first-type sampling point has the same or similar sampling accuracy as the second-type sampling point, thus improving the sampling accuracy of the first-type sampling point in the sampling circuit and ensuring a high accuracy of the sampling result.

[0065] To facilitate understanding, the implementation process of each step is described below with examples.

[0066] According to some embodiments of the present application, optionally, S102, determining a calibration factor corresponding to the first type of sampling point according to the voltage of the first type of sampling point and the voltage of the second type of sampling point, may specifically include the following steps:

[0067] The calibration factors corresponding to the first type of sampling points are determined according to the voltages of the first type of sampling points at multiple moments and the voltages of the second type of sampling points at multiple moments.

[0068] In some embodiments, the calibration factor may include two or more parameters to be determined. Therefore, in S102, the calibration factor corresponding to the first type of sampling point may be determined based on the voltages of the first type of sampling point obtained at multiple moments (e.g., two or more moments) and the voltages of the second type of sampling point obtained at multiple moments.

[0069] It should be noted that in other embodiments of the present application, the calibration factor may also include, for example, a parameter to be determined. Accordingly, in S102, the calibration factor corresponding to the first type of sampling point may be determined based on the voltage of the first type of sampling point obtained at a time and the voltage of the second type of sampling point obtained at a time, but the present application is not limited thereto.

[0070] FIG3 is a flow chart of S102 in the sampling circuit calibration method provided in an embodiment of the present application. As shown in FIG3 , according to some embodiments of the present application, optionally, S102, determining the calibration factor corresponding to the first type of sampling point based on the voltage of the first type of sampling point and the voltage of the second type of sampling point, may specifically include the following steps S301 and S302:

[0071] S301 : Establishing a relationship between the voltages of the first type of sampling points and the voltages of the second type of sampling points at multiple moments according to the voltages of the first type of sampling points and the voltages of the second type of sampling points at multiple moments.

[0072] S302 : Determine a calibration factor corresponding to the first type of sampling point according to a relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point.

[0073] The multiple moments can be two or more moments. When determining the calibration factors corresponding to the first type of sampling points, the relationship between the voltages of the first type of sampling points and the voltages of the second type of sampling points can be established or determined based on the voltages of the first type of sampling points at the multiple moments and the voltages of the second type of sampling points at the multiple moments. Then, after obtaining the relationship between the voltages of the first type of sampling points and the voltages of the second type of sampling points, the calibration factors corresponding to the first type of sampling points can be determined.

[0074] FIG4 is another flow chart of a sampling circuit calibration method according to an embodiment of the present application. As shown in FIG4 , according to some embodiments of the present application, optionally, step S101, obtaining the voltage of the first type of sampling point and the voltage of the second type of sampling point, may specifically include the following steps S401 and S402.

[0075] S401 : At a first moment, obtain voltages at first type sampling points and voltages at second type sampling points.

[0076] For example, at the first moment t1 , the voltage V11 of the first type of sampling point and the voltage V21 of the second type of sampling point may be collected.

[0077] S402 : At a second moment, obtain the voltage of the first type of sampling point and the voltage of the second type of sampling point.

[0078] For example, at the second time t2 , the voltage V12 of the first type of sampling point and the voltage V22 of the second type of sampling point may be collected.

[0079] Among them, the first moment and the second moment are different moments, and the time interval between the first moment and the second moment can be flexibly adjusted according to actual conditions, and the embodiments of the present application do not limit this.

[0080] Accordingly, S102 , determining the calibration factors corresponding to the first type of sampling points according to the voltages of the first type of sampling points and the voltages of the second type of sampling points, may specifically include the following steps S403 to S405 .

[0081] S403 : Establish a first relationship between the voltages of the first type of sampling points and the voltages of the second type of sampling points according to the voltages of the first type of sampling points acquired at the first moment and the voltages of the second type of sampling points acquired at the first moment.

[0082] For example, in some examples, the expression of the first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is as follows: V21=K*V11+B (1)

[0083] The calibration factors corresponding to the first type of sampling points may include a first calibration parameter K and a second calibration parameter B.

[0084] S404 : Establish a second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point acquired at the second moment and the voltage of the second type of sampling point acquired at the second moment.

[0085] For example, in some examples, the expression of the second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is as follows: V22=K*V12+B (2)

[0086] S405: Determine the calibration factors corresponding to the first type of sampling points according to the first relationship and the second relationship.

[0087] For example, by combining the expression (1) of the first relationship and the expression (2) of the second relationship, the sizes of the calibration factors K and B corresponding to the first type of sampling points can be calculated.

[0088] FIG5 is a flow chart of step S103 in the sampling circuit calibration method provided in an embodiment of the present application. As shown in FIG5 , according to some embodiments of the present application, S103, optionally correcting the voltage of the first type of sampling point based on the calibration factor to obtain the corrected voltage of the first type of sampling point, may include the following steps S501 and S502.

[0089] S501: Calculate the product of the voltage of a first type of sampling point and a first calibration parameter.

[0090] S502 : Calculate the sum of the product and the second calibration parameter to obtain the calibrated voltage of the first type of sampling point.

[0091] For example, in some examples, the voltage of the first type of sampling point can be corrected according to the following expression: V1x'=K*V1x+B (3)

[0092] Wherein, V1x represents the voltage of the first type of sampling point, V1x' represents the voltage of the first type of sampling point after correction, K represents the first calibration parameter, and B represents the second calibration parameter.

[0093] According to some embodiments of the present application, the reference potentials of the first type of sampling points and the second type of sampling points may optionally be different. For example, the voltage of the first type of sampling points may include the voltage of the first type of sampling points relative to a first reference potential, and the voltage of the second type of sampling points may include the voltage of the second type of sampling points relative to a second reference potential. The first reference potential and the second reference potential may be different.

[0094] For example, assuming that the actual voltage of the first type of sampling point is +4V and the voltage of the first reference potential is +2.5V, the voltage of the first type of sampling point collected can be the voltage difference between the actual voltage of the first type of sampling point and the voltage of the first reference potential, such as +1.5V.

[0095] For example, assuming that the actual voltage of the second type sampling point is +4V and the voltage of the second reference potential is 0V, the collected voltage of the second type sampling point can be the voltage difference between the actual voltage of the second type sampling point and the voltage of the second reference potential, such as +4V.

[0096] In some embodiments, S403, establishing a first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point obtained at the first moment and the voltage of the second type of sampling point obtained at the first moment, may include the following steps:

[0097] A first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is established according to the voltage difference between the first reference potential and the second reference potential, the voltage of the first type of sampling point obtained at the first moment, and the voltage of the second type of sampling point obtained at the first moment.

[0098] For example, in some examples, the expression of the first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is as follows: V21=K*V11+B+ΔV (4)

[0099] The calibration factors corresponding to the first type of sampling points may include a first calibration parameter K and a second calibration parameter B, and ΔV represents a voltage difference between the first reference potential and the second reference potential.

[0100] In some embodiments, S404, establishing a second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point obtained at the second moment and the voltage of the second type of sampling point obtained at the second moment, may include the following steps:

[0101] A second relationship between the voltages of the first and second sampling points is established according to the voltage difference between the first reference potential and the second reference potential, the voltages of the first sampling points acquired at the second moment, and the voltages of the second sampling points acquired at the second moment.

[0102] For example, in some examples, the expression of the second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is as follows: V22=K*V12+B+ΔV (5)

[0103] The calibration factors corresponding to the first type of sampling points may include a first calibration parameter K and a second calibration parameter B, and ΔV represents a voltage difference between the first reference potential and the second reference potential.

[0104] In S405 , for example, by combining the expression (4) of the first relationship and the expression (5) of the second relationship, the magnitudes of the calibration factors K and B corresponding to the first type of sampling points can be calculated.

[0105] According to some embodiments of the present application, optionally, S502, calculating the sum of the product and the second calibration parameter to obtain the corrected voltage of the first type of sampling point, may include the following steps:

[0106] The voltage difference between the first reference potential and the second reference potential, the product of the voltage of the first type of sampling point and the first calibration parameter, and the sum of the second calibration parameter are calculated to obtain the corrected voltage of the first type of sampling point.

[0107] For example, in some examples, the voltage of the first type of sampling point can be corrected according to the following expression: V1x'=K*V1x+B+ΔV (6)

[0108] Wherein, V1x represents the voltage of the first type of sampling point, V1x' represents the voltage of the first type of sampling point after correction, K represents the first calibration parameter, B represents the second calibration parameter, and ΔV represents the voltage difference between the first reference potential and the second reference potential.

[0109] Figure 6 is another circuit connection diagram of a sampling circuit provided in an embodiment of the present application. As shown in Figure 6, according to some embodiments of the present application, the first-type sampling branch 101 can optionally be electrically connected to the first reference voltage terminal Vref, and the second-type sampling branch 102 can be electrically connected to the second reference voltage terminal V2. The first reference potential can include the potential of the first reference voltage terminal Vref, and the second reference potential can include the potential of the second reference voltage terminal V2. For example, the second reference voltage terminal V2 can be the ground terminal GND.

[0110] FIG7 is another flow chart of a sampling circuit calibration method provided in an embodiment of the present application. As shown in FIG7 , according to some embodiments of the present application, optionally, before determining the calibration factor corresponding to the first type of sampling point based on the voltage of the first type of sampling point and the voltage of the second type of sampling point in S102, the sampling circuit calibration method may further include the following steps:

[0111] S701: Determine whether the difference between the voltage of the first sampling point and the voltage of the second sampling point is less than or equal to a preset error threshold. The preset error threshold can be flexibly adjusted according to actual conditions and is not limited in this embodiment of the application.

[0112] If the difference between the voltage of the first type of sampling point and the voltage of the second type of sampling point is greater than the preset error threshold, it means that the first type of sampling branch where the first type of sampling point is located has a fault and can be reported for repair.

[0113] Accordingly, S102, determining the calibration factors corresponding to the first type of sampling points according to the voltages of the first type of sampling points and the voltages of the second type of sampling points, may specifically include the following steps:

[0114] When the difference between the voltage of the first type of sampling point and the voltage of the second type of sampling point is less than or equal to the preset error threshold, a calibration factor corresponding to the first type of sampling point is determined according to the voltage of the first type of sampling point and the voltage of the second type of sampling point.

[0115] FIG8 is another circuit connection diagram of a sampling circuit provided in an embodiment of the present application. As shown in FIG8 , according to some embodiments of the present application, the first-type sampling branch 101 may optionally include a first sampling branch 601. A first end of the first sampling branch 601 is electrically connected to a first electrode of the device under test 20, and a second end of the first sampling branch 601 is electrically connected to a first reference voltage terminal Vref. The first-type sampling point UL1 may include a first sampling point U1 located in the first sampling branch 601. For example, the first electrode of the device under test 20 may be the positive electrode of the device under test 20.

[0116] The second sampling branch 102 may include a second sampling branch 602. A first end of the second sampling branch 602 is electrically connected to the first electrode of the device under test 20, and a second end of the second sampling branch 602 is electrically connected to the second reference voltage terminal V2. The second sampling point 602 may include a second sampling point U2 located in the second sampling branch 602. The switch module K may include a first switch module K1. When the first switch module K1 is turned on, the second sampling point U2 performs sampling.

[0117] In some embodiments, a first calibration factor corresponding to the first sampling point may be calculated based on the voltage at the first sampling point and the voltage at the second sampling point.

[0118] For example, in some examples, a voltage V11a at a first sampling point U1 and a voltage V21a at a second sampling point U2 may be collected at a first time t1. At a second time t2, a voltage V12a at the first sampling point U1 and a voltage V22a at the second sampling point U2 may be collected. Next, a first relationship between the voltages at the first sampling point and the second sampling point is established based on the voltage difference between the voltage at the first reference voltage terminal and the voltage at the second reference voltage terminal, and the voltages at the first sampling point and the second sampling point acquired at the first time. A second relationship between the voltages at the first sampling point and the second sampling point is established based on the voltage difference between the voltage at the first reference voltage terminal and the voltage at the second reference voltage terminal, and the voltages at the first sampling point and the second sampling point acquired at the second time.

[0119] The first relationship between the voltage at the first sampling point and the voltage at the second sampling point is expressed as follows: V21a=K1*V11a+B1+ΔV (7)

[0120] K1 and B1 are first calibration factors corresponding to the first sampling point U1 , and ΔV represents a voltage difference between the voltage at the first reference voltage terminal and the voltage at the second reference voltage terminal.

[0121] For example, in some examples, the expression of the second relationship between the voltage at the first sampling point and the voltage at the second sampling point is as follows: V22a=K1*V12a+B1+ΔV (8)

[0122] For example, by combining the expression (7) of the first relationship and the expression (8) of the second relationship, the magnitudes of the first calibration factors K1 and B1 corresponding to the first sampling point U1 can be calculated.

[0123] Accordingly, in some embodiments, the voltage at the first sampling point may be corrected based on the first calibration factor to obtain a corrected voltage at the first sampling point.

[0124] For example, in some examples, the voltage at the first sampling point may be corrected according to the following expression: V1ax'=K1*V1ax+B1+ΔV (9)

[0125] Wherein, V1ax represents the voltage at the first sampling point, and V1ax′ represents the voltage at the first sampling point after correction.

[0126] Continuing with FIG. 8 , according to some embodiments of the present application, the first-type sampling branch 101 may optionally include a third sampling branch 603. A first end of the third sampling branch 603 is electrically connected to the first reference voltage terminal Vref, and a second end of the third sampling branch 603 is electrically connected to the second electrode of the device under test 20. For example, the second electrode of the device under test 20 may be the cathode of the device under test 20. The first-type sampling point UL1 may include a third sampling point U3 located in the third sampling branch 603.

[0127] The second type of sampling branch 102 may include a fourth sampling branch 604, wherein a first end of the fourth sampling branch 604 is electrically connected to the second reference voltage terminal V2, and a second end of the fourth sampling branch 604 is electrically connected to the second electrode of the device under test 20. The second type of sampling point UL2 may include a fourth sampling point U4 located in the fourth sampling branch 604. The switch module K may include a second switch module K2, and the fourth sampling point U4 performs sampling when the second switch module K2 is turned on.

[0128] In some embodiments, a second calibration factor corresponding to the third sampling point may be calculated based on the voltage at the third sampling point and the voltage at the fourth sampling point.

[0129] The process of determining the second calibration factor may refer to the process of determining the calibration factor and the first calibration factor, and will not be described in detail here.

[0130] In some embodiments, the voltage at the third sampling point may be corrected based on the second calibration factor to obtain a corrected voltage at the third sampling point.

[0131] The calibration process of the voltage at the third sampling point may refer to the calibration process of the voltage at the first type of sampling point and the calibration process of the voltage at the first sampling point, and will not be described in detail here.

[0132] Continuing with FIG. 8 , according to some embodiments of the present application, optionally, the sampling circuit 10 may further include a third switch module K3 , wherein a first end of the third switch module K3 is electrically connected to a first electrode of the device under test 20 .

[0133] The first-type sampling branch 101 may further include a fifth sampling branch 605. A first end of the fifth sampling branch 605 is electrically connected to the second end of the third switch module K3, and a second end of the fifth sampling branch 605 is electrically connected to the first reference voltage terminal Vref. The first-type sampling point UL1 may further include a fifth sampling point U5 located in the fifth sampling branch 605.

[0134] In some embodiments, a third calibration factor corresponding to the fifth sampling point may be calculated based on the voltage at the fifth sampling point and the voltage at the second sampling point.

[0135] The process of determining the third calibration factor may refer to the process of determining the calibration factor and the first calibration factor, and will not be described in detail here.

[0136] In some embodiments, the voltage at the fifth sampling point may be corrected based on the third calibration factor to obtain a corrected voltage at the fifth sampling point.

[0137] The voltage calibration process of the fifth sampling point may refer to the voltage calibration process of the first type of sampling points and the voltage calibration process of the first sampling point, and will not be described in detail here.

[0138] Continuing with FIG. 8 , according to some embodiments of the present application, optionally, the sampling circuit 10 may further include a fourth switch module K4 , wherein a first end of the fourth switch module K4 is electrically connected to the second electrode of the device under test 20 .

[0139] The first-type sampling branch 101 may further include a sixth sampling branch 606. A first end of the sixth sampling branch 606 is electrically connected to the first reference voltage terminal Vref, and a second end of the sixth sampling branch 606 is electrically connected to the second end of the fourth switch module K4. The first-type sampling point UL1 may further include a sixth sampling point U6 located in the sixth sampling branch 606.

[0140] In some embodiments, a fourth calibration factor corresponding to the sixth sampling point may be calculated based on the voltage at the sixth sampling point and the voltage at the fourth sampling point.

[0141] The process of determining the fourth calibration factor may refer to the process of determining the calibration factor and the first calibration factor, and will not be described in detail here.

[0142] In some embodiments, the voltage at the sixth sampling point may be corrected based on the fourth calibration factor to obtain a corrected voltage at the sixth sampling point.

[0143] The voltage calibration process of the sixth sampling point may refer to the voltage calibration process of the first type of sampling points and the voltage calibration process of the first sampling point, and will not be described in detail here.

[0144] FIG9 is another circuit connection diagram of a sampling circuit provided in an embodiment of the present application. As shown in FIG9 , according to some embodiments of the present application, the sampling circuit 10 may optionally further include a sampling processing module 701. The sampling processing module 701 may be electrically connected to the first-type sampling point UL1 and the second-type sampling point UL2, respectively. The sampling processing module 701 may be configured to acquire the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2, and to correct the voltage at the first-type sampling point UL1 based on a calibration factor, where the calibration factor is determined based on the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2. In some examples, the sampling processing module 701 may include a sampling chip configured to acquire the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2, and to correct the voltage at the first-type sampling point UL1 based on the calibration factor. In other words, the sampling chip may not only be configured to acquire voltage but also to correct the voltage at the first-type sampling point based on the calibration factor.

[0145] In other examples, the sampling and processing module 701 may include a sampling chip and a processing chip, the sampling chip being electrically connected to the processing chip. The sampling chip is configured to collect the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2. The processing chip is configured to calibrate the voltage at the first-type sampling point UL1 based on a calibration factor. In other words, the sampling chip is configured only to collect voltage, while the processing chip is configured to calibrate the voltage at the first-type sampling point based on the calibration factor.

[0146] The voltage of the first reference voltage terminal Vref can be greater than 0V and less than the maximum value of the sampling range of the sampling processing module. For example, assuming that the sampling range of the sampling processing module is 0 to +5V, the maximum value of the sampling range of the sampling processing module is +5V. The voltage of the first reference voltage terminal Vref can be less than +5V.

[0147] As shown in Figures 8 and 9 , the first type of sampling points UL1 (e.g., the first sampling point U1, the third sampling point U3, the fifth sampling point U5, and the sixth sampling point U6) can be sampled relative to the first reference voltage terminal Vref. The voltage Vf at the first reference voltage terminal Vref can be greater than 0V and less than the maximum value Max-AD of the sampling range of the sampling processing module. This allows for positive and negative voltage sampling at the first type of sampling points UL1. Specifically, the voltage at the first type of sampling point UL1 with a sampling input between 0 and Vf is negative, while the voltage at the first type of sampling point UL1 with a sampling input between Vf and Max-AD is positive. By combining the various sampling points, a desired relative voltage can be converted. For example, the output voltage of the device under test 20 can be calculated based on the sum of the voltage at the first sampling point U1 and the voltage at the third sampling point U3.

[0148] As shown in Figure 8, according to some embodiments of the present application, optionally, the first sampling branch 601 may include a first voltage dividing module r1, a second voltage dividing module r2, and a first sampling point U1. Exemplarily, both the first voltage dividing module r1 and the second voltage dividing module r2 may include resistors.

[0149] A first end of the first voltage dividing module r1 is electrically connected to the first electrode of the device under test 20 , and a second end of the first voltage dividing module r1 is electrically connected to the first sampling point U1 .

[0150] A first end of the second voltage dividing module r2 is electrically connected to the first sampling point U1 , and a second end of the second voltage dividing module r2 is electrically connected to the first reference voltage end Vref.

[0151] As shown in Figure 8 , the voltage output by the first electrode of the device under test 20 can be transmitted to the first reference voltage terminal Vref via the first sampling branch 601, and then to the ground terminal GND. Therefore, when the voltage output by the first electrode of the device under test 20 is high, the components in the first sampling branch 601 may be damaged. To meet the withstand voltage requirements of the sampling circuit and to provide protection for the sampling circuit, in some embodiments, at least one of the first voltage divider module r1 and the second voltage divider module r2 can use a relatively large resistor.

[0152] For example, in some examples, the sum of the resistance of the first voltage divider module r1 and the resistance of the second voltage divider module r2 may range from 25 megohms to 30 megohms.

[0153] In this way, since the first voltage dividing module r1 and / or the second voltage dividing module r2 use resistors with relatively large resistance values, even if the voltage output by the device under test 20 is relatively large, the withstand voltage requirement of the sampling circuit can be met.

[0154] As shown in FIG8 , according to some embodiments of the present application, the second sampling branch 602 optionally includes a third voltage divider module r3, a fourth voltage divider module r4, a first switch module K1, and a second sampling point U2. The third sampling branch 603 includes a fifth voltage divider module r5, a sixth voltage divider module r6, and a third sampling point U3. The fourth sampling branch 604 includes a seventh voltage divider module r7, an eighth voltage divider module r8, a second switch module K2, and a fourth sampling point U4. The fifth sampling branch 605 includes a ninth voltage divider module r9, a tenth voltage divider module r10, and a fifth sampling point U5. The sixth sampling branch 606 includes an eleventh voltage divider module r11, a twelfth voltage divider module r12, and a sixth sampling point U6.

[0155] A first end of the third voltage dividing module r3 is electrically connected to the first electrode of the device under test 20 , and a second end of the third voltage dividing module r3 is electrically connected to the first end of the first switch module K1 .

[0156] The second end of the first switch module K1 is electrically connected to the second sampling point U2. The first end of the fourth voltage divider module r4 is electrically connected to the second sampling point U2, and the second end of the fourth voltage divider module r4 is electrically connected to the second reference voltage terminal V2.

[0157] A first end of the fifth voltage divider module r5 is electrically connected to the first reference voltage terminal Vref, and a second end of the fifth voltage divider module r5 is electrically connected to the third sampling point U3. A first end of the sixth voltage divider module r6 is electrically connected to the third sampling point U3, and a second end of the sixth voltage divider module r6 is electrically connected to the second electrode of the device under test 20.

[0158] A first end of the seventh voltage divider module r7 is electrically connected to the second reference voltage terminal V2, and a second end of the seventh voltage divider module r7 is electrically connected to a first end of the second switch module K2. A second end of the second switch module K2 is electrically connected to the fourth sampling point U4. A first end of the eighth voltage divider module r8 is electrically connected to the fourth sampling point U4, and a second end of the eighth voltage divider module r8 is electrically connected to the second electrode of the device under test 20.

[0159] A first end of the ninth voltage divider module r9 is electrically connected to the second end of the third switch module K3, and a second end of the ninth voltage divider module r9 is electrically connected to the fifth sampling point U5. A first end of the tenth voltage divider module r10 is electrically connected to the fifth sampling point U5, and a second end of the tenth voltage divider module r10 is electrically connected to the first reference voltage terminal Vref.

[0160] A first end of the eleventh voltage divider module r11 is electrically connected to the first reference voltage terminal Vref, and a second end of the eleventh voltage divider module r11 is electrically connected to the sixth sampling point U6. A first end of the twelfth voltage divider module r12 is electrically connected to the sixth sampling point U6, and a second end of the twelfth voltage divider module r12 is electrically connected to the second electrode of the device under test 20.

[0161] FIG10 is another circuit connection diagram of a sampling circuit provided in an embodiment of the present application. As shown in FIG10 , according to some embodiments of the present application, the sampling circuit 10 may further include a sampling processing module 701 and a follower 702 .

[0162] The first input terminal of the follower 702 is electrically connected to the first type of sampling point UL1. As shown in FIG6 and FIG10 , the first type of sampling point UL1 includes, but is not limited to, the first sampling point U1, the third sampling point U3, the fifth sampling point U5, and the sixth sampling point U6. That is, the first sampling point U1, the third sampling point U3, the fifth sampling point U5, and the sixth sampling point U6 can all be electrically connected to the first input terminal of the follower 702.

[0163] The second input terminal of the follower 702 can be electrically connected to the output terminal of the follower 702, the first power input terminal of the follower 702 is electrically connected to the positive power supply voltage signal terminal VCC, the second power input terminal of the follower 702 is electrically connected to the ground terminal GND, and the output terminal of the follower 702 is electrically connected to the voltage collection terminal of the sampling and processing module 701.

[0164] The potential reference terminal of the sampling and processing module 701 is electrically connected to the ground terminal GND. The sampling and processing module 701 can be used to collect the voltage of the first type of sampling point UL1.

[0165] The internal resistance of the sampling processing module 701 is relatively large. Therefore, when the resistance of the voltage divider module in the first-type sampling branch 101 is relatively small, the sampling accuracy of the first-type sampling point UL1 is relatively less affected by the internal resistance of the sampling processing module 701, and the sampling accuracy of the first-type sampling point UL1 is relatively high. However, when the resistance of the voltage divider module in the first-type sampling branch 101 (such as the first voltage divider module r1 and the second voltage divider module r2 in the first sampling branch 601) is relatively large, the difference in resistance with the internal resistance of the sampling processing module 701 is relatively small, and the internal resistance of the sampling processing module 701 will cause voltage division, thereby reducing the sampling accuracy of the first-type sampling point UL1.

[0166] Since the follower 702 has the characteristics of high-impedance input and high-impedance output, adding the follower 702 between the first-type sampling point UL1 and the sampling and processing module 701 is equivalent to isolating the voltage divider module in the first-type sampling branch 101 from the internal resistance in the sampling and processing module 701, thereby reducing the influence of the internal resistance in the sampling and processing module 701 on the sampling accuracy of the first-type sampling point UL1, and ensuring that the first-type sampling point UL1 still has high sampling accuracy when the resistance value of the voltage divider module in the first-type sampling branch 101 is large.

[0167] The follower 702 also has an amplification function, that is, it can amplify the voltage of the first type sampling point UL1 by a preset multiple before transmitting it to the sampling processing module 701. The preset multiple can be flexibly adjusted according to actual conditions, and this embodiment of the application does not limit this.

[0168] For example, in some embodiments, the follower 702 may amplify the image at a preset multiple of 1:1. In other embodiments, the follower 702 may amplify the image at a preset multiple of 1:n, where n is greater than 1.

[0169] Thus, when the resistance of the voltage divider module in the first sampling branch 101 is relatively large, the sampling accuracy of the first sampling point UL1 can be further improved by adding a follower to amplify the voltage value collected at the first sampling point UL1.

[0170] Based on the calibration method of the sampling circuit provided in the above embodiment, the present application also provides a sampling circuit.

[0171] As shown in FIG9 , the sampling circuit 10 provided in an embodiment of the present application may include a first-type sampling branch 101, a second-type sampling branch 102, and a sampling processing module 701. The first-type sampling branch 101 is electrically connected to the device under test 20 and is provided with a first-type voltage divider module FL1 and a first-type sampling point UL1. The second-type sampling branch 102 is electrically connected to the device under test 20 and is provided with a second-type voltage divider module FL2, a switch module K, and a second-type sampling point UL2. The sampling processing module 701 is electrically connected to the first-type sampling point UL1 and the second-type sampling point UL2, respectively. The sampling processing module 701 is configured to calibrate the voltage at the first-type sampling point UL1 based on a calibration factor, where the calibration factor is determined based on the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2.

[0172] The circuit structure of the sampling circuit has been described in detail above and will not be repeated here.

[0173] The sampling circuit of the embodiment of the present application calculates the calibration factors corresponding to the first-type sampling points using the voltages of the second-type sampling points with higher sampling accuracy, and corrects the voltages of the first-type sampling points based on the calibration factors to obtain the corrected voltages of the first-type sampling points. This allows the first-type sampling points to have the same or similar sampling accuracy as the second-type sampling points, thus improving the sampling accuracy of the first-type sampling points in the sampling circuit and ensuring a high accuracy of the sampling results.

[0174] According to some embodiments of the present application, the sampling processing module 701 may optionally include a sampling chip, which is configured to collect the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2, and to calibrate the voltage at the first-type sampling point UL1 based on a calibration factor. That is, the sampling chip can not only collect voltages but also calibrate the voltages at the first-type sampling points based on the calibration factor.

[0175] According to some embodiments of the present application, the sampling and processing module 701 may optionally include a sampling chip and a processing chip. The sampling chip is electrically connected to the processing chip. The sampling chip is configured to collect the voltage at the first-type sampling point UL1 and the voltage at the second-type sampling point UL2. The processing chip is configured to calibrate the voltage at the first-type sampling point UL1 based on a calibration factor. In other words, the sampling chip is configured only to collect voltage, while the processing chip is configured to calibrate the voltage at the first-type sampling point based on the calibration factor.

[0176] According to some embodiments of the present application, optionally, the first-type sampling branch is electrically connected to the first reference voltage terminal, and the second-type sampling branch is electrically connected to the second reference voltage terminal; the voltage of the first-type sampling point includes the voltage of the first-type sampling point relative to the first reference voltage terminal, and the voltage of the second-type sampling point includes the voltage of the second-type sampling point relative to the second reference voltage terminal.

[0177] According to some embodiments of the present application, optionally, the first type of sampling branch includes a first sampling branch, a first end of the first sampling branch is electrically connected to the first electrode of the device under test, and a second end of the first sampling branch is electrically connected to the first reference voltage terminal, and the first type of sampling point includes a first sampling point located in the first sampling branch; the second type of sampling branch includes a second sampling branch, a first end of the second sampling branch is electrically connected to the first electrode of the device under test, and a second end of the second sampling branch is electrically connected to the second reference voltage terminal, and the second type of sampling point includes a second sampling point located in the second sampling branch, and the switch module includes a first switch module, and the second sampling point performs sampling when the first switch module is turned on.

[0178] According to some embodiments of the present application, optionally, the first type of sampling branch includes a third sampling branch, a first end of the third sampling branch is electrically connected to the first reference voltage end, and a second end of the third sampling branch is electrically connected to the second electrode of the device under test, and the first type of sampling point includes a third sampling point located in the third sampling branch; the second type of sampling branch includes a fourth sampling branch, a first end of the fourth sampling branch is electrically connected to the second reference voltage end, and a second end of the fourth sampling branch is electrically connected to the second electrode of the device under test, and the second type of sampling point includes a fourth sampling point located in the fourth sampling branch, and the switch module includes a second switch module, and the fourth sampling point performs sampling when the second switch module is turned on.

[0179] According to some embodiments of the present application, optionally, the sampling circuit further includes a third switch module, a first end of the third switch module is electrically connected to the first electrode of the device under test; the first type of sampling branch further includes a fifth sampling branch, a first end of the fifth sampling branch is electrically connected to the second end of the third switch module, and a second end of the fifth sampling branch is electrically connected to the first reference voltage end; the first type of sampling point further includes a fifth sampling point located in the fifth sampling branch.

[0180] According to some embodiments of the present application, optionally, the sampling circuit further includes a fourth switch module, a first end of the fourth switch module is electrically connected to the second electrode of the device under test; the first type of sampling branch further includes a sixth sampling branch, a first end of the sixth sampling branch is electrically connected to the first reference voltage end, and a second end of the sixth sampling branch is electrically connected to the second end of the fourth switch module; and the first type of sampling point further includes a sixth sampling point located in the sixth sampling branch.

[0181] The circuit structure of the sampling circuit has been described in detail above and will not be repeated here.

[0182] According to some embodiments of the present application, optionally, the voltage of the first reference voltage terminal is greater than 0V and less than the maximum value of the sampling range of the sampling chip.

[0183] According to some embodiments of the present application, optionally, the first sampling branch includes a first voltage divider module, a second voltage divider module and a first sampling point; the first end of the first voltage divider module is electrically connected to the first electrode of the device under test, and the second end of the first voltage divider module is electrically connected to the first sampling point; the first end of the second voltage divider module is electrically connected to the first sampling point, and the second end of the second voltage divider module is electrically connected to the first reference voltage end; the sum of the resistance values ​​of the first voltage divider module and the second voltage divider module has a value range of 25-30 megohms.

[0184] As shown in FIG8 , according to some embodiments of the present application, the second sampling branch 602 optionally includes a third voltage divider module r3, a fourth voltage divider module r4, a first switch module K1, and a second sampling point U2. The third sampling branch 603 includes a fifth voltage divider module r5, a sixth voltage divider module r6, and a third sampling point U3. The fourth sampling branch 604 includes a seventh voltage divider module r7, an eighth voltage divider module r8, a second switch module K2, and a fourth sampling point U4. The fifth sampling branch 605 includes a ninth voltage divider module r9, a tenth voltage divider module r10, and a fifth sampling point U5. The sixth sampling branch 606 includes an eleventh voltage divider module r11, a twelfth voltage divider module r12, and a sixth sampling point U6.

[0185] A first end of the third voltage dividing module r3 is electrically connected to the first electrode of the device under test 20 , and a second end of the third voltage dividing module r3 is electrically connected to the first end of the first switch module K1 .

[0186] The second end of the first switch module K1 is electrically connected to the second sampling point U2. The first end of the fourth voltage divider module r4 is electrically connected to the second sampling point U2, and the second end of the fourth voltage divider module r4 is electrically connected to the second reference voltage terminal V2.

[0187] A first end of the fifth voltage divider module r5 is electrically connected to the first reference voltage terminal Vref, and a second end of the fifth voltage divider module r5 is electrically connected to the third sampling point U3. A first end of the sixth voltage divider module r6 is electrically connected to the third sampling point U3, and a second end of the sixth voltage divider module r6 is electrically connected to the second electrode of the device under test 20.

[0188] A first end of the seventh voltage divider module r7 is electrically connected to the second reference voltage terminal V2, and a second end of the seventh voltage divider module r7 is electrically connected to a first end of the second switch module K2. A second end of the second switch module K2 is electrically connected to the fourth sampling point U4. A first end of the eighth voltage divider module r8 is electrically connected to the fourth sampling point U4, and a second end of the eighth voltage divider module r8 is electrically connected to the second electrode of the device under test 20.

[0189] A first end of the ninth voltage divider module r9 is electrically connected to the second end of the third switch module K3, and a second end of the ninth voltage divider module r9 is electrically connected to the fifth sampling point U5. A first end of the tenth voltage divider module r10 is electrically connected to the fifth sampling point U5, and a second end of the tenth voltage divider module r10 is electrically connected to the first reference voltage terminal Vref.

[0190] A first end of the eleventh voltage divider module r11 is electrically connected to the first reference voltage terminal Vref, and a second end of the eleventh voltage divider module r11 is electrically connected to the sixth sampling point U6. A first end of the twelfth voltage divider module r12 is electrically connected to the sixth sampling point U6, and a second end of the twelfth voltage divider module r12 is electrically connected to the second electrode of the device under test 20.

[0191] According to some embodiments of the present application, optionally, the sampling circuit also includes a follower; the first input terminal of the follower is electrically connected to the first type of sampling point, the second input terminal of the follower is electrically connected to the output terminal of the follower, the first power input terminal of the follower is electrically connected to the positive power supply voltage signal terminal, the second power input terminal of the follower is electrically connected to the ground terminal, and the output terminal of the follower is electrically connected to the voltage collection terminal of the sampling chip; the potential reference terminal of the sampling chip is electrically connected to the ground terminal.

[0192] Based on the sampling circuit 10 provided in the above embodiment, the present application further provides a battery management system (BMS). The battery management system provided in the embodiment of the present application may include the sampling circuit 10 provided in the above embodiment.

[0193] The battery management system provided in the embodiment of the present application calculates the calibration factors corresponding to the first-type sampling points using the voltages of the second-type sampling points with higher sampling accuracy, and corrects the voltages of the first-type sampling points based on the calibration factors to obtain the corrected voltages of the first-type sampling points. This ensures that the first-type sampling points have the same or similar sampling accuracy as the second-type sampling points, thus improving the sampling accuracy of the first-type sampling points in the sampling circuit and ensuring a high accuracy of the sampling results.

[0194] Based on the sampling circuit 10 or battery management system provided in the above embodiment, the present application further provides an electrical device, which includes the sampling circuit 10 or the battery management system provided in the above embodiment. In some specific embodiments, the electrical device can optionally be a vehicle. The vehicle can be a fuel vehicle, a gas vehicle, or a new energy vehicle. The new energy vehicle can be a pure electric vehicle, a hybrid vehicle, or an extended-range vehicle.

[0195] Although the present application has been described with reference to preferred embodiments, various modifications may be made thereto and components may be replaced with equivalents without departing from the scope of the present application. In particular, the various technical features described in the various embodiments may be combined in any manner as long as there are no structural conflicts. The present application is not limited to the specific embodiments disclosed herein, but includes all technical solutions within the scope of the claims.

Claims

1. A calibration method for a sampling circuit, comprising: Obtaining the voltage of the first type of sampling point and the voltage of the second type of sampling point; Determine a calibration factor corresponding to the first type of sampling point according to the voltage of the first type of sampling point and the voltage of the second type of sampling point; Based on the calibration factor, the voltage of the first-type sampling point is corrected to obtain the corrected voltage of the first-type sampling point.

2. The calibration method according to claim 1, wherein: The step of determining the calibration factors corresponding to the first-type sampling points according to the voltages of the first-type sampling points and the voltages of the second-type sampling points includes: The calibration factors corresponding to the first-type sampling points are determined according to the voltages of the first-type sampling points at multiple moments and the voltages of the second-type sampling points at multiple moments.

3. The calibration method according to claim 1 or 2, wherein: The step of determining the calibration factors corresponding to the first-type sampling points according to the voltages of the first-type sampling points and the voltages of the second-type sampling points includes: According to the voltages of the first type of sampling points at multiple moments and the voltages of the second type of sampling points at multiple moments, establishing a relationship between the voltages of the first type of sampling points and the voltages of the second type of sampling points; According to the relationship between the voltage of the first-type sampling point and the voltage of the second-type sampling point, a calibration factor corresponding to the first-type sampling point is determined.

4. The calibration method according to any one of claims 1 to 3, wherein: The step of determining the calibration factors corresponding to the first-type sampling points according to the voltages of the first-type sampling points and the voltages of the second-type sampling points includes: Establishing a first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point acquired at a first moment and the voltage of the second type of sampling point acquired at the first moment; Establishing a second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point acquired at a second moment and the voltage of the second type of sampling point acquired at the second moment; According to the first relationship and the second relationship, a calibration factor corresponding to the first type of sampling points is determined.

5. The calibration method according to claim 4, wherein: The voltage of the first type of sampling point includes the voltage of the first type of sampling point relative to a first reference potential, and the voltage of the second type of sampling point includes the voltage of the second type of sampling point relative to a second reference potential; Establishing a first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point obtained at a first moment, comprising: A first relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is established according to the voltage difference between the first reference potential and the second reference potential, the voltage of the first type of sampling point acquired at the first moment, and the voltage of the second type of sampling point acquired at the first moment.

6. The calibration method according to claim 5, wherein: The establishing a second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point according to the voltage of the first type of sampling point acquired at the second moment and the voltage of the second type of sampling point acquired at the second moment comprises: A second relationship between the voltage of the first type of sampling point and the voltage of the second type of sampling point is established according to the voltage difference between the first reference potential and the second reference potential, the voltage of the first type of sampling point acquired at the second moment, and the voltage of the second type of sampling point acquired at the second moment.

7. The calibration method according to any one of claims 1 to 6, wherein: The calibration factor includes a first calibration parameter and a second calibration parameter; The step of correcting the voltage of the first type of sampling point based on the calibration factor to obtain the corrected voltage of the first type of sampling point includes: Calculating the product of the voltage of the first type of sampling point and the first calibration parameter; The sum of the product and the second calibration parameter is calculated to obtain the corrected voltage of the first type of sampling point.

8. The calibration method according to claim 7, wherein: The voltage of the first type of sampling point includes the voltage of the first type of sampling point relative to a first reference potential, and the voltage of the second type of sampling point includes the voltage of the second type of sampling point relative to a second reference potential; The calculating the sum of the product and the second calibration parameter to obtain the corrected voltage of the first type of sampling point includes: The voltage difference between the first reference potential and the second reference potential, the sum of the product and the second calibration parameter are calculated to obtain the corrected voltage of the first type of sampling point.

9. A sampling circuit comprising: A first type of sampling branch, the first type of sampling branch is electrically connected to the device under test, and the first type of sampling branch is provided with a first type of voltage dividing module and a first type of sampling point; A second type of sampling branch, the second type of sampling branch is electrically connected to the device under test, and the second type of sampling branch is provided with a second type of voltage divider module, a switch module, and a second type of sampling point; A sampling processing module, the sampling processing module is electrically connected to the first type of sampling points and the second type of sampling points respectively, and the sampling processing module is used to correct the voltage of the first type of sampling points based on a calibration factor, and the calibration factor is determined according to the voltage of the first type of sampling points and the voltage of the second type of sampling points.

10. The sampling circuit according to claim 9, wherein: The first type of sampling branch is electrically connected to the first reference voltage terminal, and the second type of sampling branch is electrically connected to the second reference voltage terminal; The voltages of the first-type sampling points include voltages of the first-type sampling points relative to the first reference voltage terminal, and the voltages of the second-type sampling points include voltages of the second-type sampling points relative to the second reference voltage terminal.

11. The sampling circuit according to claim 9 or 10, wherein: The first type of sampling branch includes a first sampling branch, a first end of the first sampling branch is electrically connected to a first electrode of the device under test, a second end of the first sampling branch is electrically connected to a first reference voltage end, and the first type of sampling point includes a first sampling point located in the first sampling branch; The second type of sampling branch includes a second sampling branch, a first end of the second sampling branch and the The first electrode of the device is electrically connected, the second end of the second sampling branch is electrically connected to the second reference voltage end, the second type of sampling point includes a second sampling point located in the second sampling branch, the switch module includes a first switch module, and the second sampling point performs sampling when the first switch module is turned on.

12. The sampling circuit according to any one of claims 9 to 11, wherein: The first type of sampling branch includes a third sampling branch, a first end of the third sampling branch is electrically connected to the first reference voltage end, a second end of the third sampling branch is electrically connected to the second electrode of the device under test, and the first type of sampling point includes a third sampling point located in the third sampling branch; The second type of sampling branch includes a fourth sampling branch, a first end of the fourth sampling branch is electrically connected to the second reference voltage end, a second end of the fourth sampling branch is electrically connected to the second electrode of the device under test, the second type of sampling point includes a fourth sampling point located in the fourth sampling branch, the switch module includes a second switch module, and the fourth sampling point performs sampling when the second switch module is turned on.

13. The sampling circuit according to any one of claims 9 to 12, wherein: The sampling circuit further includes a third switch module, a first end of the third switch module is electrically connected to the first electrode of the device under test; The first type of sampling branch also includes a fifth sampling branch, a first end of the fifth sampling branch is electrically connected to the second end of the third switch module, a second end of the fifth sampling branch is electrically connected to the first reference voltage end, and the first type of sampling point also includes a fifth sampling point located in the fifth sampling branch.

14. The sampling circuit according to any one of claims 9 to 13, wherein: The sampling circuit further includes a fourth switch module, a first end of the fourth switch module is electrically connected to the second electrode of the device under test; The first type of sampling branch also includes a sixth sampling branch, a first end of the sixth sampling branch is electrically connected to the first reference voltage end, a second end of the sixth sampling branch is electrically connected to the second end of the fourth switch module, and the first type of sampling point also includes a sixth sampling point located in the sixth sampling branch.

15. The sampling circuit according to any one of claims 9 to 14, wherein: The voltage of the first reference voltage terminal is greater than 0V and less than the maximum value of the sampling range of the sampling chip.

16. The sampling circuit according to any one of claims 9 to 15, wherein: The first sampling branch includes a first voltage dividing module, a second voltage dividing module and the first sampling point; A first end of the first voltage divider module is electrically connected to a first electrode of the device under test, and a second end of the first voltage divider module is electrically connected to the first sampling point; A first end of the second voltage dividing module is electrically connected to the first sampling point, and a second end of the second voltage dividing module is electrically connected to the first reference voltage end; The sum of the resistance of the first voltage divider module and the resistance of the second voltage divider module ranges from 25 to 30 megohms.

17. The sampling circuit according to any one of claims 9 to 16, wherein: The sampling circuit also includes a follower; The first input terminal of the follower is electrically connected to the first type of sampling point, the second input terminal of the follower is electrically connected to the output terminal of the follower, the first power input terminal of the follower is electrically connected to the positive power supply voltage signal terminal, the second power input terminal of the follower is electrically connected to the ground terminal, and the output terminal of the follower is electrically connected to the voltage collection terminal of the sampling chip; The potential reference terminal of the sampling chip is electrically connected to the ground terminal.

18. A battery management system, comprising the sampling circuit according to any one of claims 9 to 17.

19. An electrical device comprising the battery management system according to claim 18.

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