Signal sampling circuit, battery management system, battery system and electric apparatus

Abstract

Disclosed in the present application are a signal sampling circuit, a battery management system, a battery system and an electric apparatus. The signal sampling circuit comprises a voltage dividing module, a switch module and a sampling module, wherein the voltage dividing module and the switch module are connected in series between a point to be measured and a reference signal end of the sampling module, a control end of the switch module is connected to an enabling signal end of the sampling module, and the sampling module is connected to a first reference ground; and a sampling point is provided in the voltage dividing module, and the sampling module is configured to collect a sampling signal of the sampling point. According to the embodiments of the present application, a reduction in the cost of a signal sampling circuit is facilitated.

Description

Signal sampling circuit, battery management system, battery system and power consumption device

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims priority to Chinese patent application No. 202323277335.1 filed on November 30, 2023, entitled “Signal sampling circuit, battery management system, battery system and electrical device,” and the entire contents of that application are incorporated herein by reference. Technical Field

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

[0004] With the continuous development of battery technology, people's requirements for batteries are getting higher and higher.

[0005] In the related art, a signal sampling circuit is provided to sample the test point, but the signal sampling circuit in the related art has the problem of high cost.

[0006] Summary of the Invention

[0007] Embodiments of the present application provide a signal sampling circuit, a battery management system, a battery system, and an electrical device, which help reduce the cost of the signal sampling circuit.

[0008] In a first aspect, the present application provides a signal sampling circuit, comprising a voltage divider module, a switch module and a sampling module; wherein,

[0009] The voltage divider module and the switch module are connected in series between the point to be measured and the reference signal terminal of the sampling module, the control terminal of the switch module is connected to the enable signal terminal of the sampling module, and the sampling module is connected to the first reference ground;

[0010] The voltage divider module is provided with a sampling point, and the sampling module is used to collect the sampling signal of the sampling point.

[0011] In an embodiment of the present application, a voltage divider module and a switch module are arranged in series between the point to be measured and the reference signal end of the sampling module, the control end of the switch module is connected to the enable signal end of the sampling module, and the sampling module is connected to the first reference ground. When the point to be measured is a high-voltage point to be measured, the first reference ground can be a high-voltage ground, and the sampling module is connected to the high-voltage ground. Therefore, the sampling module is on the high-voltage side, so that the control end and the controlled end of the switch module are both located on the high-voltage side. Therefore, the control end and the controlled end of the switch module help to reduce the cost of the signal sampling circuit compared to using devices with high insulation and withstand voltage.

[0012] In an optional embodiment of the first aspect, the signal sampling circuit further includes a unidirectional conduction module. The unidirectional conduction module, the switch module, and the voltage divider module are connected in series between the point to be measured and the signal acquisition terminal of the sampling module. The unidirectional conduction module is configured to control the flow of current from the point to be measured to the sampling module. Thus, by providing the unidirectional conduction module in series with the switch module and the voltage divider module to control the flow of current from the point to be measured to the sampling module, the risk of a potential loop in the signal sampling circuit remaining even when the switch module is turned off is reduced.

[0013] In an optional embodiment of the first aspect, the voltage divider module includes a first resistor and a second resistor, the first resistor and the second resistor are connected in series, and the sampling point is set between the first resistor and the second resistor. In this way, by providing the first resistor and the second resistor connected in series with the first resistor, and setting the sampling point between the first resistor and the second resistor, the voltage value of the point to be measured can be calculated based on the sampling signal collected by the sampling module at the sampling point and the voltage divider resistance of the second resistor. In addition, by providing a diode in the unidirectional conduction module, the current can be controlled to flow from the point to be measured to the sampling module, thereby reducing the risk of potential loops in the signal sampling circuit.

[0014] In an optional embodiment of the first aspect, the signal sampling circuit further includes a level conversion module, the level conversion module being connected between the enable signal terminal and the control terminal of the switch module. The level conversion module is configured to perform level conversion on the control signal at the enable signal terminal and provide the level-converted control signal to the control terminal of the switch module. Thus, by providing the level conversion module connected between the enable signal terminal and the control terminal of the switch module, if the control signal from the sampling module does not meet a condition for driving the switch module to turn on and is insufficient to drive the switch module, the level conversion module provides the level-converted control signal to the switch module, thereby facilitating driving the switch module to turn on or off.

[0015] In an optional embodiment of the first aspect, the level conversion module includes a first switch submodule and a second switch submodule, the control end of the first switch submodule is connected to the enable signal end, the first end of the first switch submodule is connected to the first reference ground, the second end of the first switch submodule is connected to the control end of the second switch submodule, the first end of the second switch submodule is connected to the high-voltage power supply end, and the second end of the second switch submodule is connected to the first reference ground and the control end of the switch module; the first switch submodule is used to turn on or off under the control of the control signal, and the second switch submodule is used to turn on or off under the control of the first switch submodule to perform level conversion on the control signal and provide the converted control signal to the control end of the switch module. In this way, by setting a first switch submodule connected to the enable signal end and a second switch submodule connected to the second end of the first switch submodule, the first switch submodule can be turned on or off when the enable signal end provides a control signal, thereby controlling the second switch submodule to be turned on or off, thereby performing level conversion on the control signal, so that when the control signal of the sampling module does not meet the turn-on condition of the driving switch module and is insufficient to drive the switch module, the control signal after level conversion is provided to the switch module, which helps to drive the switch module to be turned on or off.

[0016] In an optional embodiment of the first aspect, the level conversion module further includes a third switch submodule, wherein a control terminal of the third switch submodule is connected to the second terminal of the first switch submodule, a first terminal of the third switch submodule is connected to the second terminal of the second switch submodule, and a second terminal of the third switch submodule is connected to the first reference ground. The third switch submodule is configured to be turned on or off under the control of the first switch submodule to perform level conversion on the control signal and provide the converted control signal to the control terminal of the switch module. Thus, by setting the control terminal of the third switch submodule to be connected to the second terminal of the first switch submodule, the first switch submodule can be turned off when a non-enable signal is provided at the enable signal terminal, thereby controlling the third switch submodule to turn off. Thus, when the non-enable signal from the sampling module does not meet the on-condition for driving the switch module and is insufficient to drive the switch module to turn off, the non-enable signal after level conversion is provided to the switch module, thereby facilitating the driving of the switch module to turn off.

[0017] In an optional embodiment of the first aspect, the level conversion module further includes a current limiting submodule connected between the control terminal of the switch module and the second terminal of the second switch submodule; and / or the level conversion module further includes a reset submodule connected between the control terminal of the switch module and the first reference ground, the reset submodule being configured to reset the control terminal of the switch module. Thus, by providing the current limiting submodule in the level conversion module, the current between the control terminal of the switch module and the second terminal of the second switch submodule is reduced, thereby helping to protect the control terminal of the switch module and the second terminal of the second switch submodule. Furthermore, providing the reset submodule in the level conversion module facilitates resetting the control terminal of the switch module.

[0018] In an optional embodiment of the first aspect, the current limiting submodule includes a third resistor; and / or the reset submodule includes a fourth resistor. Thus, by providing the third resistor in the current limiting submodule, the current between the control terminal of the switch module and the second terminal of the second switch submodule is reduced, thereby helping to protect the control terminal of the switch module and the second terminal of the second switch submodule. Furthermore, by providing the fourth resistor in the reset submodule, the control terminal of the switch module is facilitated to reset.

[0019] In an optional embodiment of the first aspect, the level conversion module further includes a current limiting submodule, which is connected between the control terminal of the switch module and the second terminal of the second switch submodule. Thus, by providing the current limiting submodule in the level conversion module, the current between the control terminal of the switch module and the second terminal of the second switch submodule is reduced, thereby helping to protect the control terminal of the switch module and the second terminal of the second switch submodule.

[0020] In an optional embodiment of the first aspect, the current limiting submodule includes a third resistor. Thus, by providing the third resistor in the current limiting submodule, the current between the control terminal of the switch module and the second terminal of the second switch submodule is reduced, thereby helping to protect the control terminal of the switch module and the second terminal of the second switch submodule.

[0021] In an optional embodiment of the first aspect, the first switch submodule, the second switch submodule, and the third switch submodule all include transistors. Thus, by providing transistors in the first switch submodule, the second switch submodule, and the third switch submodule, and then controlling the on / off state of each transistor, when the control signal from the sampling module does not meet the on condition for driving the switch module and is insufficient to drive the switch module to turn off, a level-converted control signal is provided to the switch module, thereby facilitating driving the switch module to turn on or off.

[0022] In an optional embodiment of the first aspect, the level conversion module further includes a first voltage divider submodule, the first voltage divider submodule being connected between the high-voltage power supply terminal and the second terminal of the first switch submodule, and a voltage dividing node of the first voltage divider submodule being connected to the control terminal of the second switch submodule; and / or the level conversion module further includes a second voltage divider submodule, the second voltage divider submodule being connected between the enable signal terminal and the first reference ground, and a voltage dividing node of the second voltage divider submodule being connected to the control terminal of the first switch submodule. Thus, by providing the first voltage divider submodule between the high-voltage power supply terminal and the second terminal of the first switch submodule, and by providing the voltage dividing node of the first voltage divider submodule being connected to the control terminal of the second switch submodule, the voltage at the control terminal of the second switch submodule is reduced, thereby helping to protect the second switch submodule. Furthermore, by providing the second voltage divider submodule between the enable signal terminal and the first reference ground, and by providing the voltage dividing node of the second voltage divider submodule being connected to the control terminal of the first switch submodule, the voltage at the control terminal of the first switch submodule is reduced, thereby helping to protect the first switch submodule.

[0023] In an optional embodiment of the first aspect, the first voltage divider module includes a fifth resistor and a sixth resistor, the fifth resistor and the sixth resistor are connected in series, and the voltage dividing node of the first voltage divider module is set between the fifth resistor and the sixth resistor; and / or the second voltage divider module includes a seventh resistor and an eighth resistor, the seventh resistor and the eighth resistor are connected in series, and the voltage dividing node of the second voltage divider module is set between the seventh resistor and the eighth resistor. In this way, the fifth resistor and the sixth resistor are set in series in the first voltage divider module, and the voltage at the control end of the second switch submodule is reduced by the voltage division between the fifth resistor and the sixth resistor, thereby helping to protect the second switch submodule; and the voltage at the control end of the second switch submodule can be flexibly controlled by controlling the resistance between the fifth resistor and the sixth resistor. In addition, the seventh resistor and the eighth resistor are set in series in the second voltage divider module, and the voltage at the control end of the first switch submodule is reduced by the voltage division between the seventh resistor and the eighth resistor, thereby helping to protect the first switch submodule; and the voltage at the control end of the first switch submodule can be flexibly controlled by controlling the resistance between the seventh resistor and the eighth resistor.

[0024] Based on the same inventive concept, in a second aspect, the present application also provides a battery management system. The battery management system includes:

[0025] Controller;

[0026] Isolation communication module;

[0027] and the signal sampling circuit of any one of the first aspects, wherein the sampling module in the signal sampling circuit is connected to the controller via the isolation communication module;

[0028] The controller is configured as:

[0029] Sending a sampling instruction to the sampling module through the isolated communication module, the sampling instruction is used to instruct the sampling module to collect a sampling signal and transmit the sampling signal to the controller through the isolated communication module;

[0030] Receive the sampled signal.

[0031] In an embodiment of the present application, the controller sends a sampling instruction to the sampling module through the isolated communication module, so that the sampling module collects the sampling signal, and transmits the sampling signal to the controller through the isolated communication module, and receives the sampling signal, which helps the controller calculate the voltage of the point to be measured based on the sampling signal.

[0032] In an optional implementation of the second aspect, the sampling module further includes a unidirectional conduction module, the unidirectional conduction module includes a diode, and the controller is further configured to:

[0033] Obtain the voltage drop value of the diode at the target temperature and the initial voltage value of the test point at the target temperature, the initial voltage value is calculated based on the sampling signal;

[0034] Use the voltage drop value to calibrate the initial voltage value.

[0035] In this way, the controller obtains the voltage drop value of the diode at the target temperature and the initial voltage value of the test point at the target temperature, and then uses the voltage drop value to calibrate the initial voltage value to improve the problem of error in the determined voltage of the test point caused by the influence of temperature on the diode voltage drop, thereby improving the accuracy of the voltage of the test point.

[0036] Based on the same inventive concept, in a third aspect, an embodiment of the present application further provides a battery system, comprising a battery and the battery management system of any one of the second aspects.

[0037] Based on the same inventive concept, in a fourth aspect, an embodiment of the present application further provides an electrical device, comprising the battery management system of any one of the second aspects.

[0038] The above description is only an overview of the technical solution of the present application. In order to more clearly understand the technical means of the present application, it can be implemented in accordance with the contents of the specification. In order to make the above and other purposes, features and advantages of the present application more obvious and easy to understand, the specific implementation methods of the present application are listed below. BRIEF DESCRIPTION OF THE DRAWINGS

[0039] The features, advantages and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

[0040] FIG1 is a schematic structural diagram of a signal sampling circuit according to an embodiment of the present application;

[0041] FIG2 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

[0042] FIG3 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

[0043] FIG4 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

[0044] FIG5 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

[0045] FIG6 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

[0046] FIG7 is a schematic structural diagram of a level conversion module in a signal sampling circuit according to an embodiment of the present application;

[0047] FIG8 is a schematic structural diagram of another level conversion module in a signal sampling circuit according to another embodiment of the present application;

[0048] FIG9 is a schematic structural diagram of a battery management system according to an embodiment of the present application;

[0049] FIG10 is a schematic structural diagram of a battery system according to an embodiment of the present application;

[0050] FIG11 is a schematic structural diagram of an electrical device according to an embodiment of the present application.

[0051] Explanation of component symbols: 10. Signal sampling circuit; 11. Voltage divider module; 12. Switch module; 13. Sampling module; 14. One-way conduction module; 15. Level conversion module; 151. First switch sub-module; 152. Second switch sub-module; 153. Third switch sub-module; 154. Current limiting sub-module; 155. Reset sub-module; 156. First voltage divider sub-module; 157. Second voltage divider sub-module; 16. Positive switch module; 20. Isolation communication module; 30. Controller; 100. Battery management system; 200. Battery; 1000. Battery system; 2000. Electrical device; S, sampling point; EN2, enable signal terminal; HV-GND, first reference ground; LV-GND, second reference ground; HV1, point to be measured; Vref, reference signal terminal; V1, signal acquisition terminal; VCC, high voltage power supply terminal. DETAILED DESCRIPTION

[0052] 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.

[0053] Unless otherwise defined, all technical and scientific terms used in this application have the same meanings as commonly understood by those skilled in the art to which this application belongs. The terms used in the specification of this application are for the purpose of describing specific embodiments only and are not intended to limit this application. The terms "including" and "having" and any variations thereof in the specification and claims of this application and the above-mentioned drawings are intended to cover non-exclusive inclusions. The terms "first" and "second" in the specification and claims of this application or the above-mentioned drawings are used to distinguish different objects, rather than to describe a specific order or a primary-secondary relationship.

[0054] In the description of this application, it should be noted that, unless otherwise expressly specified or limited, the terms "mounted," "connected," "connected," and "attached" should be understood in a broad sense. For example, they may refer to fixed connections, detachable connections, or integral connections; they may refer to direct connections, indirect connections through an intermediate medium, or internal connections between two components. Those skilled in the art will understand the specific meanings of the above terms in this application based on specific circumstances.

[0055] In the description of the embodiments of this application, the term "and / or" is simply a description of the association relationship between associated objects, indicating that three relationships can exist. For example, A and / or B can represent the following three situations: A exists alone, A and B exist simultaneously, and B exists alone. In addition, the character " / " in this document generally indicates that the associated objects are in an "or" relationship.

[0056] The signal sampling circuit in the related art needs to have the function of high insulation and voltage resistance, but the cost of electronic devices with high insulation and voltage resistance is high, which leads to the problem of high cost of the signal sampling circuit in the related art.

[0057] The embodiments of the present application provide a signal sampling circuit, a battery management system, a battery system, and an electric device. The signal sampling circuit, the battery management system, the battery system, and the electric device provided in the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0058] The following first introduces the signal sampling circuit provided by the application embodiment.

[0059] As shown in FIG. 1 , the signal sampling circuit 10 may include a voltage dividing module 11 , a switch module 12 and a sampling module 13 .

[0060] The voltage divider module 11 and the switch module 12 can be connected in series between the test point HV1 and the reference signal terminal Vref of the sampling module 13. The control terminal of the switch module 12 can be connected to the enable signal terminal EN2 of the sampling module 13. The sampling module 13 can be connected to the first reference ground HV-GND.

[0061] Exemplarily, the test point HV1 may be connected to the positive electrode of the battery pack BAT to be tested.

[0062] For example, the first reference ground HV-GND may be the negative electrode of the battery pack to be tested. In other words, the first reference ground HV-GND may be a high voltage ground.

[0063] For example, the switch module 12 may include a metal-oxide-semiconductor field-effect transistor (MOSFET), a MOS transistor, a relay, etc. As shown in FIG3 to FIG9 , the transistor may be an N-type MOS transistor Q2.

[0064] For example, the sampling module 13 may include a sampling chip. The sampling chip may be used to collect sampling signals from the sampling point S and control the switching module 12 to be turned on or off. The sampling chip may include an analog-to-digital converter (ADC) that converts the collected sampling signals from analog signals to digital signals.

[0065] Exemplarily, the first reference ground HV-GND can serve as the reference signal terminal Vref, that is, the signal value of the first reference ground HV-GND can be equal to the signal value of the reference signal terminal Vref. The control terminal of the switch module 12 can be connected to the enable signal terminal EN2 of the sampling module 13, and the control signal of the enable signal terminal EN2 can control the switch module 12 to be turned on or off. Exemplarily, the control signal may include an enable signal and a disable signal. The switch module 12 can be turned on when the enable signal terminal EN2 outputs an enable signal, and can also be turned off when the enable signal terminal EN2 outputs a disable signal. In other words, the enable signal can be a signal that can turn on the switch module 12, and the disable signal can be a signal that can turn off the switch module 12. For example, when the switch module 12 includes a P-type MOS tube or an NPN transistor, the enable signal can be a low-level signal, and the disable signal can be a high-level signal. For another example, when the switch module 12 includes an N-type MOS transistor or a PNP transistor, the enable signal may be a high-level signal, and the disable signal may be a low-level signal.

[0066] A sampling point S may be provided in the voltage dividing module 11 , and the sampling module 13 may be used to collect a sampling signal at the sampling point S.

[0067] For example, the sampling signal may be the voltage value of the sampling point S.

[0068] In an embodiment of the present application, a voltage divider module and a switch module are arranged in series between the point to be measured and the reference signal end of the sampling module, the control end of the switch module is connected to the enable signal end of the sampling module, and the sampling module is connected to the first reference ground. When the point to be measured is a high-voltage point to be measured, the first reference ground can be a high-voltage ground, and the sampling module is connected to the high-voltage ground. Therefore, the sampling module is on the high-voltage side, so that the control end and the controlled end of the switch module are both located on the high-voltage side. Therefore, the control end and the controlled end of the switch module help to reduce the cost of the signal sampling circuit compared to using devices with high insulation and withstand voltage.

[0069] In some optional embodiments, as shown in FIG2 , the signal sampling circuit 10 may further include a unidirectional conduction module 14. The unidirectional conduction module 14, the switch module 12, and the voltage divider module 11 may be connected in series between the test point HV1 and the signal acquisition terminal V1 of the sampling module 13. The unidirectional conduction module 14 may be used to control the flow of current from the test point HV1 to the sampling module 13. Thus, by providing the unidirectional conduction module 14 in series with the switch module 12 and the voltage divider module 11, the current is controlled to flow from the test point HV1 to the sampling module 13, thereby reducing the risk of potential loops in the signal sampling circuit when the switch module 12 is turned off.

[0070] The signal acquisition terminal V1 of the sampling module 13 can be used to acquire the sampling signal of the sampling point S.

[0071] 3 to 6 , the unidirectional conduction module 14 may include a diode D1 . By providing the diode D1 in the unidirectional conduction module 14 , the current can be controlled to flow from the test point HV1 to the sampling module 13 , thereby reducing the risk of potential loops in the signal sampling circuit 10 .

[0072] In some optional embodiments, as shown in Figures 3 to 6, the voltage divider module 11 may include a first resistor R1 and a second resistor R2, which may be connected in series, and the sampling point S may be set between the first resistor R1 and the second resistor R2. In this way, by providing the first resistor R1 and the second resistor R2 connected in series with the first resistor R1, and setting the sampling point S between the first resistor R1 and the second resistor R2, the voltage value of the test point HV1 can be calculated based on the sampling signal collected by the sampling module 13 at the sampling point S and the voltage divider resistance of the second resistor R2.

[0073] It should be understood that Figures 3 through 6 illustrate a signal sampling circuit including two first resistors R1. In specific implementations, the number of first resistors R1 can be set based on actual conditions and is not limited here. For example, the number of first resistors R1 can be one, three, or four. The number and resistance of first resistors R1 can be determined by the voltage at the test point HV1.

[0074] The second resistor R2 can be a sampling resistor.

[0075] As an example, as shown in FIG3 , the diode D1 may be connected between the switch module 12 and the second resistor R2 .

[0076] As another example, as shown in FIG. 4 , a diode D1 may be connected between the switch module 12 and the first resistor R1 .

[0077] As another example, as shown in FIG5 , the diode D1 may be connected between the two first resistors R1 .

[0078] As another example, as shown in FIG6 , the diode D1 may be connected between the test point HV1 and the first resistor R1 .

[0079] It should be noted that, in the embodiment of the present application, the anode of the diode D1 is electrically connected to the test point HV1 , and the cathode of the diode D1 is electrically connected to the reference signal terminal Vref.

[0080] In some optional embodiments, as shown in Figures 2 to 6, the signal sampling circuit 10 may further include a level conversion module 15. The level conversion module 15 may be connected between the enable signal terminal EN2 and the control terminal of the switch module 12. The level conversion module 15 may be used to convert the level of the control signal of the enable signal terminal EN2 and provide the level-converted control signal to the control terminal of the switch module 12. In this way, by providing the level conversion module 15 connected between the enable signal terminal EN2 and the control terminal of the switch module 12, when the control signal of the sampling module 13 does not meet the conditions for driving the switch module 12 to turn on and is insufficient to drive the switch module 12, the level conversion module 15 provides the level-converted control signal to the switch module 12, thereby helping to drive the switch module 12 to turn on or off.

[0081] In some optional embodiments, as shown in Figures 7 and 8, the level conversion module 15 may include a first switch submodule 151 and a second switch submodule 152, the control end of the first switch submodule 151 may be connected to the enable signal end EN2, the first end of the first switch submodule 151 may be connected to the first reference ground HV-GND, the second end of the first switch submodule 151 may be connected to the control end of the second switch submodule 152, the first end of the second switch submodule 152 may be connected to the high-voltage power supply end VCC, and the second end of the second switch submodule 152 may be connected to the first reference ground HV-GND and the control end of the switch module 12; the first switch submodule 151 may be used to turn on or off under the control of the control signal, and the second switch submodule 152 may be used to turn on or off under the control of the first switch submodule 151, so as to perform level conversion on the control signal and provide the converted control signal to the control end of the switch module 12.

[0082] In this way, by providing a first switch submodule 151 connected to the enable signal terminal EN2 and a second switch submodule 152 connected to the second end of the first switch submodule 151, the first switch submodule 151 can be turned on or off when the enable signal terminal EN2 provides a control signal, thereby controlling the second switch submodule 152 to be turned on or off, thereby performing level conversion on the control signal, so that when the control signal of the sampling module 13 does not meet the turn-on condition of driving the switch module 12 and is insufficient to drive the switch module 12, the control signal after level conversion is provided to the switch module 12, which helps to drive the switch module 12 to be turned on or off.

[0083] Optionally, the first switch submodule 151 and the second switch submodule 152 may each include a transistor. Thus, by providing transistors in both the first switch submodule 151 and the second switch submodule 152 and controlling the on / off state of each transistor, when the control signal from the sampling module 13 does not meet the on condition for driving the switch module 12 and is insufficient to drive the switch module 12 off, a level-converted control signal is provided to the switch module 12, thereby facilitating driving the switch module 12 on or off.

[0084] For example, as shown in Figures 7 and 8, the first switch submodule 151 may include an N-type MOS transistor Q3, or the first switch submodule 151 may also include a PNP transistor; the second switch submodule 152 may include a P-type MOS transistor Q4, or the second switch submodule 152 may also include an NPN transistor.

[0085] For example, the high-voltage power supply terminal VCC may be a power supply of about 10 V to 20 V with reference to the first reference ground HV-GND. The high-voltage power supply terminal VCC may be used to drive the MOS transistor.

[0086] In some optional embodiments, as shown in Figure 8, the level conversion module 15 may further include a third switch submodule 153, the control end of the third switch submodule 153 can be connected to the second end of the first switch submodule 151, the first end of the third switch submodule 153 can be connected to the second end of the second switch submodule 152, and the second end of the third switch submodule 153 can be connected to the first reference ground HV-GND. The third switch submodule 153 can be used to turn on or off under the control of the first switch submodule 151 to perform level conversion on the control signal and provide the converted control signal to the control end of the switch module 12.

[0087] In this way, by setting the control end of the third switch sub-module 153 to be connected to the second end of the first switch sub-module 151, the first switch sub-module 151 can be turned off when the enable signal end EN2 provides a non-enable signal, thereby controlling the third switch sub-module 153 to be turned off. In this way, when the non-enable signal of the sampling module 13 does not meet the turn-on condition of the driving switch module 12 and is insufficient to drive the switch module 12 to turn off, the non-enable signal after level conversion is provided to the switch module 12, which helps to drive the switch module 12 to turn off.

[0088] Optionally, the third switch submodule 153 may include a transistor. Thus, by providing the transistor in the third switch submodule 153 and controlling the on / off state of the transistor, when the control signal from the sampling module 13 does not meet the on condition for driving the switch module 12 and is insufficient to drive the switch module 12 to turn off, a level-converted control signal is provided to the switch module 12, thereby facilitating driving the switch module 12 to turn on or off.

[0089] For example, as shown in FIG8 , the third switch submodule 153 may include an N-type MOS transistor Q4 , or may also include a PNP transistor.

[0090] In some optional embodiments, as shown in FIG. 7 , the level conversion module 15 may further include a current limiting submodule 154 . The current limiting submodule 154 may be connected between the control terminal of the switch module 12 and the second terminal of the second switch submodule 152 .

[0091] Thus, by providing the current limiting submodule 154 in the level conversion module 15 , the current between the control end of the switch module 12 and the second end of the second switch submodule 152 is reduced, thereby helping to protect the control end of the switch module 12 and the second end of the second switch submodule 152 .

[0092] Optionally, the current limiting submodule 154 may include a third resistor R3. Thus, by providing the third resistor R3 in the current limiting submodule 154, the current between the control terminal of the switch module 12 and the second terminal of the second switch submodule 152 is reduced, thereby helping to protect the control terminal of the switch module 12 and the second terminal of the second switch submodule 152.

[0093] In some optional embodiments, as shown in FIG7 , the level conversion module 15 may further include a reset submodule 155. The reset submodule 155 is connected between the control terminal of the switch module 12 and the first reference ground HV-GND. The reset submodule 155 may be used to reset the control terminal of the switch module 12. Thus, providing the reset submodule 155 in the level conversion module 15 facilitates resetting the control terminal of the switch module 12.

[0094] Optionally, the reset submodule 155 may include a fourth resistor R4. Thus, providing the fourth resistor R4 in the reset submodule 155 facilitates resetting the control terminal of the switch module 12. Furthermore, after the N-type MOS transistor Q4 is turned off, the fourth resistor R4 can be used to discharge the capacitive charge between the gate and source of the N-type MOS transistor Q2, thereby facilitating the turning off of the N-type MOS transistor Q2.

[0095] In some optional embodiments, as shown in FIG8 , the level conversion module 15 may further include a current limiting submodule 154, which may be connected between the control terminal of the switch module 12 and the second terminal of the second switch submodule 152. Thus, by providing the current limiting submodule 154 in the level conversion module 15, the current between the control terminal of the switch module 12 and the second terminal of the second switch submodule 152 is reduced, thereby helping to protect the control terminal of the switch module 12 and the second terminal of the second switch submodule 152.

[0096] Optionally, the current limiting submodule 154 may include a third resistor R3. Thus, by providing the third resistor R3 in the current limiting submodule 154, the current between the control terminal of the switch module 12 and the second terminal of the second switch submodule 152 is reduced, thereby helping to protect the control terminal of the switch module 12 and the second terminal of the second switch submodule 152.

[0097] In some optional embodiments, as shown in Figures 7 and 8, the level conversion module 15 may further include a first voltage divider submodule 156. The first voltage divider submodule 156 may be connected between the high-voltage power supply terminal VCC and the second end of the first switch submodule 151, and the voltage dividing node of the first voltage divider submodule 156 may be connected to the control end of the second switch submodule 152. Thus, by providing the first voltage divider submodule 156 between the high-voltage power supply terminal VCC and the second end of the first switch submodule 151, and connecting the voltage dividing node of the first voltage divider submodule 156 to the control end of the second switch submodule 152, the voltage at the control end of the second switch submodule 152 is reduced, thereby helping to protect the second switch submodule 152.

[0098] In some optional embodiments, the first voltage divider submodule 156 may include a fifth resistor R5 and a sixth resistor R6, which may be connected in series. The voltage dividing node of the first voltage divider submodule 156 may be located between the fifth resistor R5 and the sixth resistor R6. Thus, by providing the fifth resistor R5 and the sixth resistor R6 in series in the first voltage divider submodule 156, the voltage divided between the fifth resistor R5 and the sixth resistor R6 helps reduce the voltage at the control terminal of the second switch submodule 152, thereby helping to protect the second switch submodule 152. Furthermore, the voltage at the control terminal of the second switch submodule 152 can be flexibly controlled by controlling the resistance value between the fifth resistor R5 and the sixth resistor R6.

[0099] In some optional embodiments, as shown in Figures 7 and 8, the level conversion module 15 may further include a second voltage divider submodule 157. The second voltage divider submodule 157 may be connected between the enable signal terminal EN2 and the first reference ground HV-GND, and the voltage dividing node of the second voltage divider submodule 157 may be connected to the control terminal of the first switch submodule 151. In this way, by providing the second voltage divider submodule 157 between the enable signal terminal EN2 and the first reference ground HV-GND, and connecting the voltage dividing node of the second voltage divider submodule 157 to the control terminal of the first switch submodule 151, it helps to reduce the voltage at the control terminal of the first switch submodule 151, thereby helping to protect the first switch submodule 151.

[0100] In some optional embodiments, the second voltage divider submodule 157 may include a seventh resistor R7 and an eighth resistor R8, which may be connected in series. The voltage dividing node of the second voltage divider submodule 157 may be located between the seventh resistor R7 and the eighth resistor R8. Thus, by providing the seventh resistor R7 and the eighth resistor R8 in series in the second voltage divider submodule 157, the voltage divided between the seventh resistor R7 and the eighth resistor R8 helps reduce the voltage at the control terminal of the first switch submodule 151, thereby helping to protect the first switch submodule 151. Furthermore, the voltage at the control terminal of the first switch submodule 151 can be flexibly controlled by controlling the resistance value between the seventh resistor R7 and the eighth resistor R8.

[0101] As an example, as shown in FIG7 , when the enable signal terminal EN2 outputs a high-level signal, the N-type MOS transistor Q3 is turned on, and the control terminal of the P-type MOS transistor Q4 is a low-level signal, the P-type MOS transistor Q4 is turned on, and the control terminal of the N-type MOS transistor Q2 is a high-level signal, and the N-type MOS transistor Q2 is turned on. When the enable signal terminal EN2 outputs a low-level signal, the N-type MOS transistor Q3 is turned off, and the control terminal of the P-type MOS transistor Q4 is a high-level signal, the P-type MOS transistor Q4 is turned off, and the control terminal of the N-type MOS transistor Q2 is a low-level signal, and the N-type MOS transistor Q2 is turned off.

[0102] As another example, as shown in FIG8 , when the enable signal terminal EN2 outputs a high-level signal, the N-type MOS transistor Q3 is turned on, and the control terminal of the P-type MOS transistor Q4 is a low-level signal, the P-type MOS transistor Q4 is turned on, the control terminal of the N-type MOS transistor Q5 is a low-level signal, the N-type MOS transistor Q5 is turned off, the control terminal of the N-type MOS transistor Q2 is a high-level signal, and the N-type MOS transistor Q2 is turned on. When the enable signal terminal EN2 outputs a low-level signal, the N-type MOS transistor Q3 is turned off, and the control terminal of the P-type MOS transistor Q4 is a high-level signal, the P-type MOS transistor Q4 is turned off, the control terminal of the N-type MOS transistor Q5 is a high-level signal, the N-type MOS transistor Q5 is turned on, the control terminal of the N-type MOS transistor Q2 is a low-level signal, and the N-type MOS transistor Q2 is turned off.

[0103] Optionally, as shown in FIG. 3 to FIG. 6 , the signal sampling circuit 10 may further include a positive switch module 16 . The positive switch module 16 may be connected between the positive electrode of the battery pack BAT to be tested and the test point HV1 .

[0104] For example, the positive switch module 16 may include a switch K2 , and the switch K2 may include a relay.

[0105] Based on the same inventive concept, an embodiment of the present application also provides a battery management system.

[0106] As shown in FIG9 , the battery management system 100 provided in an embodiment of the present application may include:

[0107] Controller 30;

[0108] Isolation communication module 20;

[0109] And the signal sampling circuit 10 in any of the above embodiments, the sampling module 13 in the signal sampling circuit 10 is connected to the controller 30 via the isolation communication module 20;

[0110] The controller 30 may be configured to:

[0111] Sending a sampling instruction to the sampling module 13 through the isolated communication module 20, the sampling instruction is used to instruct the sampling module 13 to collect a sampling signal and transmit the sampling signal to the controller 30 through the isolated communication module 20;

[0112] Receive the sampled signal.

[0113] In an embodiment of the present application, the controller 30 sends a sampling instruction to the sampling module 13 through the isolated communication module 20, so that the sampling module 13 collects the sampling signal, and transmits the sampling signal to the controller 30 through the isolated communication module 20, and receives the sampling signal, which helps the controller 30 calculate the voltage of the test point HV1 based on the sampling signal.

[0114] For example, the controller 30 may include a microcontroller unit (MCU). The isolated communication module 20 may include an isolated communication chip. The isolated communication module 20 may send a sampling instruction to the sampling module 13 via a serial peripheral interface (SPI), an integrated circuit (I2C), a universal asynchronous receiver / transmitter (UART), or a daisy chain.

[0115] For example, the controller 30 may be connected to a second reference ground LV-GND. The second reference ground LV-GND may be the earth. In other words, the second reference ground LV-GND may be a low voltage ground.

[0116] For example, taking the case where there are two first resistors R1, the voltage U at the test point HV1 can satisfy the formula (1). U = (v1-vref)*(2r1+r2) / r2 Formula (1)

[0117] Wherein, v1 represents the sampling voltage at the sampling point S; vref represents the voltage of the reference signal terminal Vref in the sampling module 13; r1 represents the resistance value of the first resistor R1; and r2 represents the resistance value of the second resistor R2.

[0118] It is understandable that the values ​​of v1, vref, r1 and r2 are all known. Substituting the values ​​of v1, vref, r1 and r2 into formula (1), U can be calculated.

[0119] It should be noted that formula (1) takes the number of the first resistors R1 as an example. If the number of the first resistors R1 is N, where N is a positive integer, then “2r1” in formula (1) is “N×r1”.

[0120] In some optional embodiments, as shown in FIG9 , the sampling module 13 further includes a unidirectional conduction module 14 , which includes a diode D1 , and the controller 30 is further configured to:

[0121] Obtain the voltage drop value of the diode D1 at the target temperature and the initial voltage value of the test point HV1 at the target temperature, the initial voltage value being calculated based on the sampling signal;

[0122] Use the voltage drop value to calibrate the initial voltage value.

[0123] In this way, the controller 30 obtains the voltage drop value of the diode D1 at the target temperature and the initial voltage value of the test point HV1 at the target temperature, and then uses the voltage drop value to calibrate the initial voltage value to improve the problem of error in the determined voltage of the test point HV1 caused by the influence of temperature on the voltage drop of the diode D1, thereby improving the accuracy of the voltage of the test point HV1.

[0124] Calibrating the initial voltage value using the voltage drop value may include: taking the sum of the initial voltage value and the voltage drop value as the calibrated initial voltage value.

[0125] Exemplarily, the target temperatures include T1, T2 and T3, the voltage drop value of the diode D1 at T1 is D1, the voltage drop value of the diode D1 at T2 is D2, the voltage drop value of the diode D1 at T3 is D3, the initial voltage value of the test point HV1 at T1 is U1, the initial voltage value of the test point HV1 at T2 is U2, and the initial voltage value of the test point HV1 at T3 is U3, then the calibrated initial voltage value corresponding to the test point HV1 at T1 is U1'=U1+D1; the calibrated initial voltage value corresponding to the test point HV1 at T2 is U2'=U2+D2; the calibrated initial voltage value corresponding to the test point HV1 at T3 is U3'=U3+D3.

[0126] The specific value and number of target temperatures can be set according to actual conditions and are not limited here. For example, the specific value of the target temperature can be 20 degrees Celsius, 30 degrees Celsius, etc., and the number of target temperatures can be 1, 2, etc.

[0127] It can be understood that the battery management system has the beneficial effects of the signal sampling circuit provided in the embodiments of the present application. For details, please refer to the specific description of the signal sampling circuit in the above embodiments, which will not be repeated in this embodiment.

[0128] Based on the same inventive concept, embodiments of the present application also provide a battery system. As shown in FIG10 , a battery system 1000 may include a battery 200 and a battery management system 100. The battery management system 100 may include the signal sampling circuit of any of the above embodiments. It is understood that the battery system has the beneficial effects of the signal sampling circuit provided in the embodiments of the present application. For details, please refer to the detailed description of the signal sampling circuit in the above embodiments, and this embodiment will not be repeated here.

[0129] Based on the same inventive concept, the present embodiment also provides an electric device. As shown in Figure 11, the electric device 2000 may include a battery management system 100, which may include the signal sampling circuit of any of the above embodiments. It is understood that the electric device has the beneficial effects of the signal sampling circuit provided in the embodiments of the present application. For details, please refer to the detailed description of the signal sampling circuit in the above embodiments, and this embodiment will not be repeated here.

[0130] It should be noted that in the embodiments shown in the above figures, the resistor is shown as a single resistor. In other embodiments, the resistor may be an integration of series, parallel, or mixed resistors. The specific parameters of each device can be set according to actual needs and are not limited in this application.

[0131] It should be noted that, unless there is any conflict, the embodiments and features in the embodiments of this application can be combined with each other.

[0132] 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 signal sampling circuit, comprising a voltage divider module, a switch module and a sampling module; wherein: The voltage divider module and the switch module are connected in series between the point to be measured and the reference signal terminal of the sampling module, the control terminal of the switch module is connected to the enable signal terminal of the sampling module, and the sampling module is connected to the first reference ground; The voltage divider module is provided with a sampling point, and the sampling module is used to collect a sampling signal of the sampling point.

2. The signal sampling circuit according to claim 1, wherein: The signal sampling circuit also includes a unidirectional conduction module, wherein the unidirectional conduction module, the switch module and the voltage divider module are connected in series between the point to be measured and the signal acquisition end of the sampling module, and the unidirectional conduction module is used to control the current to flow from the point to be measured to the sampling module.

3. The signal sampling circuit according to claim 1 or 2, wherein: The voltage divider module includes a first resistor and a second resistor, the first resistor and the second resistor are connected in series, and the sampling point is arranged between the first resistor and the second resistor.

4. The signal sampling circuit according to any one of claims 1 to 3, wherein: The signal sampling circuit also includes a level conversion module, which is connected between the enable signal terminal and the control terminal of the switch module. The level conversion module is used to level convert the control signal of the enable signal terminal and provide the control signal after level conversion to the control terminal of the switch module.

5. The signal sampling circuit according to claim 4, wherein: The level conversion module comprises a first switch submodule and a second switch submodule, wherein the control end of the first switch submodule is connected to the enable signal end, the first end of the first switch submodule is connected to the first reference ground, the second end of the first switch submodule is connected to the control end of the second switch submodule, the first end of the second switch submodule is connected to the high voltage power supply end, and the second end of the second switch submodule is connected to the first reference ground and the control end of the switch module; The first switch submodule is used to turn on or off under the control of the control signal, and the second switch submodule is used to turn on or off under the control of the first switch submodule to perform level conversion on the control signal and provide the converted control signal to the control end of the switch module.

6. The signal sampling circuit according to claim 5, wherein: The level conversion module also includes a third switch submodule, a control end of the third switch submodule is connected to the second end of the first switch submodule, a first end of the third switch submodule is connected to the second end of the second switch submodule, and a second end of the third switch submodule is connected to the first reference ground, and the third switch submodule is used to be turned on or off under the control of the first switch submodule to perform level conversion on the control signal and provide the converted control signal to the control end of the switch module.

7. The signal sampling circuit according to claim 5, wherein: The level conversion module further includes a current limiting submodule, and the current limiting submodule is connected between the control end of the switch module and the second end of the second switch submodule; And / or, the level conversion module further includes a reset submodule, the reset submodule is connected between the control end of the switch module and the first reference ground, and the reset submodule is used to reset the control end of the switch module.

8. The signal sampling circuit according to claim 7, wherein: The current limiting submodule includes a third resistor; And / or, the reset submodule includes a fourth resistor.

9. The signal sampling circuit according to claim 6, wherein: The level conversion module further includes a current limiting submodule, and the current limiting submodule is connected between the control end of the switch module and the second end of the second switch submodule.

10. The signal sampling circuit according to claim 9, wherein: The current limiting submodule includes a third resistor.

11. The signal sampling circuit according to claim 6, 9 or 10, wherein: The first switch submodule, the second switch submodule and the third switch submodule each include a transistor.

12. The signal sampling circuit according to any one of claims 5 to 10, wherein: The level conversion module further includes a first voltage dividing submodule, wherein the first voltage dividing submodule is connected between the high voltage power supply terminal and the second terminal of the first switch submodule, and a voltage dividing node of the first voltage dividing submodule is connected to a control terminal of the second switch submodule; And / or, the level conversion module further includes a second voltage dividing submodule, the second voltage dividing submodule is connected between the enable signal terminal and the first reference ground, and the second voltage dividing submodule The voltage division node of the block is connected to the control end of the first switch submodule.

13. The signal sampling circuit according to claim 12, wherein: The first voltage dividing submodule comprises a fifth resistor and a sixth resistor, the fifth resistor and the sixth resistor are connected in series, and a voltage dividing node of the first voltage dividing submodule is arranged between the fifth resistor and the sixth resistor; And / or, the second voltage dividing submodule includes a seventh resistor and an eighth resistor, the seventh resistor and the eighth resistor are connected in series, and the voltage dividing node of the second voltage dividing submodule is arranged between the seventh resistor and the eighth resistor.

14. A battery management system, comprising: Controller; Isolate communication module; And the signal sampling circuit according to any one of claims 1 to 13, wherein the sampling module in the signal sampling circuit is connected to the controller through the isolation communication module; The controller is configured to: Sending a sampling instruction to the sampling module through the isolated communication module, wherein the sampling instruction is used to instruct the sampling module to collect a sampling signal and transmit the sampling signal to the controller through the isolated communication module; The sampling signal is received.

15. The battery management system according to claim 14, wherein: The sampling module further includes a unidirectional conduction module, the unidirectional conduction module includes a diode, and the controller is further configured as follows: Obtaining a voltage drop value of the diode at a target temperature and an initial voltage value of a point to be measured at the target temperature, wherein the initial voltage value is calculated based on the sampling signal; The initial voltage value is calibrated using the voltage drop value.

16. A battery system comprising a battery and the battery management system according to claim 14 or 15.

17. An electrical device comprising the battery management system according to claim 14 or 15.

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