CN220709253U

CN220709253U - Signal sampling circuit, battery management system and power utilization device

Info

Publication number: CN220709253U
Application number: CN202321940293.2U
Authority: CN
Inventors: 陈静源; 叶伏明
Original assignee: Contemporary Amperex Technology Co Ltd
Current assignee: Contemporary Amperex Technology Co Ltd
Priority date: 2023-07-21
Filing date: 2023-07-21
Publication date: 2024-04-02
Anticipated expiration: 2033-07-21

Abstract

The application discloses a signal sampling circuit, a battery management system and an electricity utilization device. The signal sampling circuit comprises a voltage division module and an analog-to-digital conversion module; the voltage dividing module is connected with a reference power supply and is provided with sampling points; the analog-to-digital conversion module is connected with the sampling point, and is used for acquiring sampling voltage from the sampling point, comparing the sampling voltage with the reference voltage of the reference power supply to obtain a comparison result, and obtaining a digital voltage signal corresponding to the sampling point according to the comparison result. According to the embodiment of the application, the sampling precision of the signal sampling circuit is improved.

Description

Signal sampling circuit, battery management system and power utilization device

Technical Field

The present disclosure relates to the field of signal acquisition technologies, and in particular, to a signal sampling circuit, a battery management system, and an electric device.

Background

The signal sampling circuit can be used for collecting signals and detecting an object to be detected according to the collected signals.

However, the signal sampling circuit in the related art has a problem of low sampling accuracy.

Disclosure of Invention

The application provides a signal sampling circuit, a battery management system and an electric device, which are beneficial to improving the sampling precision of the signal sampling circuit.

In a first aspect, the present application provides a signal sampling circuit, including a voltage division module and an analog-to-digital conversion module; the voltage dividing module is connected with a reference power supply and is provided with sampling points; the analog-to-digital conversion module is connected with the sampling point, and is used for acquiring sampling voltage from the sampling point, comparing the sampling voltage with the reference voltage of the reference power supply to obtain a comparison result, and obtaining a digital voltage signal corresponding to the sampling point according to the comparison result.

In one possible implementation manner of the first aspect, the voltage dividing module includes a first resistor and a second resistor, a first end of the first resistor is connected to the reference power supply, a second end of the first resistor is connected to a first end of the second resistor, a second end of the second resistor is connected to ground, and a sampling point is disposed between the second end of the first resistor and the first end of the second resistor.

In a possible implementation manner of the first aspect, the signal sampling circuit further includes an isolation protection module;

the voltage dividing module is connected with a reference power supply through the isolation protection module. The isolation protection module is used for reducing the influence of the voltage division module on the precision of the reference power supply.

In a possible implementation manner of the first aspect, the isolation protection module includes a voltage follower, a non-inverting input terminal of the voltage follower is connected to a reference power supply, an inverting input terminal of the voltage follower is connected to an output terminal of the voltage follower, and an output terminal of the voltage follower is connected to the voltage division module.

In a possible implementation manner of the first aspect, the first resistor is a fixed resistor, and the second resistor is a thermistor.

In a possible implementation manner of the first aspect, a distance between the second resistor and the single battery cell in the battery pack is smaller than a temperature sensing distance threshold;

the signal sampling circuit further includes a first processor for determining a temperature of the battery pack based on the digital voltage signal.

In a possible implementation manner of the first aspect, a connector is connected between the second end of the first resistor and the first end of the second resistor, the sampling points include a first sampling point and a second sampling point, the first sampling point is disposed between the second end of the first resistor and the connector, and the second sampling point is disposed between the first end of the second resistor and the connector;

the analog-to-digital conversion module is connected with the first sampling point and the second sampling point, and is used for acquiring a first sampling voltage from the first sampling point, comparing the first sampling voltage with a reference voltage of a reference power supply to obtain a first comparison result, acquiring a first digital voltage signal corresponding to the first sampling point according to the first comparison result, acquiring a second sampling voltage from the second sampling point, comparing the second sampling voltage with the reference voltage of the reference power supply to obtain a second comparison result, and acquiring a second digital voltage signal corresponding to the second sampling point according to the second comparison result;

the signal sampling circuit further includes a second processor for determining a state of the connector based on the first digital voltage signal and the second digital voltage signal.

In one possible implementation of the first aspect, the connector comprises a high voltage interlock connector.

In a possible implementation manner of the first aspect, the second resistor is a built-in resistor of the charging gun or the discharging gun;

the signal sampling circuit also comprises a third processor, and the third processor is used for determining the working current supported by the charging gun or the discharging gun according to the digital voltage signal.

In a possible implementation manner of the first aspect, the signal sampling circuit further includes a unidirectional conduction module, the unidirectional conduction module and the first resistor are connected in series between the reference power supply and the collection point, and the unidirectional conduction module is used for preventing a current flowing through the collection point from flowing into the reference power supply;

and/or the signal sampling circuit further comprises a filtering module, the filtering module is connected with the input end of the analog-to-digital conversion module, and the filtering module is used for filtering interference signals.

Based on the same inventive concept, in a second aspect, embodiments of the present application provide a battery management system, including a signal sampling circuit according to any one of the embodiments of the first aspect.

Based on the same inventive concept, in a third aspect, an embodiment of the present application provides an electrical device, including a battery management system according to any one of the embodiments of the first aspect.

According to the signal sampling circuit, the battery management system and the power utilization device, the voltage division module and the analog-to-digital conversion module are connected with the same reference power supply, the reference power supply is used as a pull-up power supply of the voltage division module, and therefore even if the reference power supply changes due to the influence of aging, temperature drift and the like, the actual voltages of the power supplies connected with the voltage division module and the analog-to-digital conversion module are the same, and the sampling precision of the signal sampling circuit is improved.

Drawings

Features, advantages, and technical effects of exemplary embodiments of the present application will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of a related art signal sampling circuit;

FIG. 2 is a schematic diagram of a signal sampling circuit according to an embodiment of the present disclosure;

fig. 3 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

fig. 4 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present disclosure;

fig. 5 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present disclosure;

fig. 6 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present application;

fig. 7 is a schematic structural diagram of a signal sampling circuit according to another embodiment of the present disclosure;

fig. 8 is a schematic diagram of a signal sampling circuit according to another embodiment of the present application.

Reference numerals illustrate:

10. a signal acquisition circuit;

11. a voltage dividing module; 12. an analog-to-digital conversion module; 13. an isolation protection module; 131. a voltage follower; 14. a first processor; 15. a connector; 16. a second processor; 17. a third processor; 18. a unidirectional conduction module; 19. and a filtering module.

Detailed Description

For the purposes of making the objects, technical solutions and advantages of the embodiments of the present application more clear, the technical solutions of the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is apparent that the described embodiments are some embodiments of the present application, but not all embodiments. All other embodiments, based on the embodiments herein, which would be apparent to one of ordinary skill in the art without making any inventive effort, are intended to be within the scope of the present application.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs; the terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application; the terms "comprising" and "having" and any variations thereof in the description and claims of the present application and in the description of the figures above are intended to cover non-exclusive inclusions. The terms first, second and the like in the description and in the claims or in the above-described figures, are used for distinguishing between different objects and not necessarily for describing a particular sequential or chronological order.

In the description of the present application, it should be noted that, unless explicitly specified and limited otherwise, the terms "mounted," "connected," and "attached" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the terms in this application will be understood by those of ordinary skill in the art as the case may be.

As shown in fig. 1, an analog-to-digital converter 02 in a related art signal sampling circuit is connected to a reference power Vref, and an independent pull-up power Vpullup is set to supply power to a first resistor R1 and a second resistor R2 of a voltage division module 01. However, the reference power Vref and the pull-up power Vpullup are different power sources, and the actual voltages of the reference power Vref and the pull-up power Vpullup are not known due to influence factors such as offset caused by aging and temperature influence of the reference power Vref and the pull-up power Vpullup. For example, the actual voltage of the reference power Vref may become large, and the actual voltage of the pull-up power Vpullup may become small. For another example, the actual voltage of the reference power Vref may become smaller, and the actual voltage of the pull-up power Vpullup may become larger. That is, the reference power Vref and the pull-up power Vpullup may have different error ratios due to aging, temperature drift, etc., and thus may cause additional errors in the sampling signals of the signal sampling circuit, thereby causing a problem that the sampling accuracy of the signal sampling circuit is not high.

In order to solve the above technical problems, the embodiments of the present application provide a signal sampling circuit, a battery management system, and an electrical device, and the signal sampling circuit, the battery management system, and the electrical device provided in the embodiments of the present application will be described in detail below with reference to the accompanying drawings.

The following first describes a signal sampling circuit provided in the application embodiment.

As shown in fig. 2, the signal sampling circuit 10 provided in the application embodiment may include a voltage dividing module 11 and an analog-to-digital conversion module 12.

The voltage dividing module 11 is connected with a reference power supply Vref, and a sampling point S is arranged in the voltage dividing module 11.

The analog-to-digital conversion module 12 is connected to the sampling point S, and the analog-to-digital conversion module 12 is configured to obtain a sampling voltage V1 from the sampling point S, compare the sampling voltage V1 with a reference voltage of the reference power Vref to obtain a comparison result, and obtain a digital voltage signal corresponding to the sampling point S according to the comparison result.

According to the signal sampling circuit 10 provided in this embodiment of the present application, the voltage division module 11 and the analog-to-digital conversion module 12 are connected to the same reference power Vref, and the reference power Vref is used as a pull-up power supply of the voltage division module 11, so that even if the reference power Vref is changed due to the influence of aging or temperature drift, etc., for the voltage division module 11 and the analog-to-digital conversion module 12, the actual voltages of the power supplies connected to the voltage division module 11 and the analog-to-digital conversion module 12 are the same, so that the aging or temperature drift, etc. of the power supplies connected to the voltage division module 11 and the analog-to-digital conversion module 12 are the same, and for the voltage division module 11 and the analog-to-digital conversion module 12, the aging or temperature drift, etc. of the different power supplies are different, so that the voltage division module 11 and the analog-to-digital conversion module 12 are connected to the same reference power Vref to help to improve the sampling precision of the signal sampling circuit 10.

For example, the analog-to-digital conversion module 12 may be a separate ADC conversion chip, or the analog-to-digital conversion module 12 may be integrated into a processor, and the processor may implement the corresponding functions. The specific structure of the analog-to-digital conversion module 12 in the embodiment of the present application is not limited as long as it can convert the sampling voltage V1 obtained from the sampling point into a digital voltage signal based on the reference voltage of the reference power Vref.

Taking the standard value of the reference voltage of the reference power Vref as 3.3V, the actual value of the reference voltage of the reference power Vref as V0 as an example, for example, the number of bits of the analog-to-digital conversion module 12 is 12 bits, and as an example, the specific conversion process of the sampling voltage V1 of the analog voltage signal by the analog-to-digital conversion module 12 can be as shown in the formula (1):

where Vai represents a digital voltage signal corresponding to the sampling voltage V1.

As shown in fig. 3, the signal sampling circuit 10 may further include an isolation protection module 13. The voltage division module 11 is connected with the reference power supply Vref through the isolation protection module 13, and the isolation protection module 13 can be used for reducing the influence of the voltage division module 11 on the precision of the reference power supply Vref.

In this embodiment of the present application, since the isolation protection module 13 may be used to reduce the influence of the voltage division module 11 on the precision of the reference power Vref, so that the precision of the reference power Vref may be guaranteed, the higher the precision of the reference power Vref, the smaller the deviation of the actual value of the reference voltage of the reference power Vref with respect to the standard value thereof, and further the sampling precision of the signal sampling circuit 10 may be further improved. In some alternative embodiments, as shown in fig. 4, the isolation protection module 13 may include a voltage follower 131, where a non-inverting input terminal of the voltage follower 131 is connected to the reference power Vref, an inverting input terminal of the voltage follower 131 is connected to an output terminal of the voltage follower, and an output terminal of the voltage follower 131 is connected to a first terminal of the first resistor R1.

The voltage follower may be a type of electronic component that implements a transformation of the output voltage following the input voltage. The voltage follower has the characteristics of high input impedance and low output impedance, so that the voltage follower can play an isolating role, and if an external circuit corresponding to the voltage division module has a short circuit fault or the current of the voltage division module is increased, the situation of further increasing the current of the reference power supply Vref can be reduced, and the situation of further reducing the precision of the reference power supply Vref can be reduced.

In addition, since the voltage follower input impedance is high, its input can be considered an open circuit. In the embodiment of the application, the non-inverting input end of the voltage follower is connected with the reference power supply Vref, and for the reference power supply Vref, the voltage follower is almost unloaded, so that the load of the reference power supply Vref is not increased, and the problem of reducing the precision of the reference power supply Vref caused by the increase of the load is solved.

Optionally, the voltage follower 131 is further connected to the first voltage terminal v+ and the ground GND. Wherein the first voltage terminal v+ may be connected to a low voltage power supply inside the battery management unit (Battery Management Unit, BMU), which may be used to provide a positive voltage, which may be greater than a reference voltage of the reference power supply Vref. For example, the reference voltage of the reference power Vref is 3.3V, and the voltage of the first voltage terminal v+ may be 5V.

In some alternative embodiments, as shown in fig. 1, the voltage dividing module 11 includes a first resistor R1 and a second resistor R2, where the first resistor R1 and the second resistor R2 are connected in series between the reference power Vref and the ground GND. The first end of the first resistor R1 is connected to the reference power Vref, the second end of the first resistor R1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is connected to the ground GND. The sampling point S is disposed between the first resistor R1 and the second resistor R2.

In some alternative embodiments, the first resistor R1 may be a fixed resistor and the second resistor R2 may be a thermistor. For example, the second resistor R2 may be a negative temperature coefficient thermistor (Negative Temperature Coefficient, NTC).

The second resistor R2 is a thermistor, the resistance of the second resistor R2 can be changed along with the change of temperature, and under the condition that the resistance of the second resistor R2 is changed, the voltage of the sampling point S is also changed, so that the resistance of the second resistor R2 can be determined by using the voltage of the sampling point S, and the temperature can be determined by using the resistance of the second resistor R2. For example, the second resistor R2 may be disposed close to the object to be measured, and thus the temperature of the object to be measured may be detected.

Since the voltage dividing module 11 and the analog-to-digital conversion module 12 are connected with the same reference power supply Vref in the embodiment of the application, the actual voltages of the power supplies connected with the voltage dividing module 11 and the analog-to-digital conversion module are the same, and further under the condition of including a voltage follower, the sampling precision of the signal sampling circuit 10 is higher, so that the precision of the resistance value of the determined second resistor R2 is higher, and further, the precision of the determined temperature is higher.

With the rapid development of new energy, the new energy can provide power for more and more devices, for example, a battery pack can be used as a power source to provide power for new energy automobiles, new energy ships, new energy aircrafts and the like. The battery pack generates heat during operation, and the change in temperature affects the operating state of the battery pack, so it is very necessary to improve the temperature detection accuracy of the battery pack.

In some alternative embodiments, in the case where the second resistor R2 is a thermistor, the distance between the second resistor R2 and the unit cell in the battery pack may be less than the temperature sensing distance threshold. As shown in fig. 5, the signal sampling circuit 10 may further include a first processor 14, where the first processor 14 is connected to the analog-to-digital conversion module 12, and the first processor 14 may be configured to determine the temperature of the battery pack according to the digital voltage signal determined by the analog-to-digital conversion module 12.

Because the voltage dividing module 11 and the analog-to-digital conversion module 12 are connected with the same reference power supply Vref in the embodiment of the application, the actual voltages of the power supplies connected with the voltage dividing module 11 and the analog-to-digital conversion module are the same, and further under the condition of including a voltage follower, the sampling precision of the signal sampling circuit 10 is higher, so that the precision of the resistance value of the determined second resistor R2 is higher, and further, the precision of the determined battery pack temperature is higher.

The temperature sensing distance threshold is a distance threshold that the second resistor R2 can sensitively sense the temperature of the single battery cell in the battery pack. Under the condition that the distance between the second resistor R2 and the single battery cell in the battery pack is smaller than the temperature sensing distance threshold value, the error between the temperature corresponding to the change of the resistance value of the second resistor R2 and the actual temperature of the single battery cell in the battery pack is within an acceptable range. The temperature sensing distance threshold can be set according to the self characteristic parameters of the second resistor R2 and the self characteristic parameters of the single battery cell in combination with specific working scenes and working requirements, and is not limited herein.

The first processor 14 may include a micro control unit (Microcontroller Unit, MCU).

In the circuit system, connectors can be arranged, so that the connection bridge can be erected through the connectors between the blocked or isolated circuits in the circuit system, and therefore current flows, and the circuits achieve preset functions. Whether the connector is connected completely or tightly affects the connectivity and integrity of the circuit, so it is necessary to improve the detection accuracy of the connector state.

In other alternative embodiments, as shown in fig. 6, the voltage dividing module 11 includes a first resistor R1 and a second resistor R2, where the first resistor R1 and the second resistor R2 are connected in series between the reference power Vref and the ground GND. The first end of the first resistor R1 is connected to the reference power Vref, the second end of the first resistor R1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is connected to the ground GND. A connector 15 is connected between the second end of the first resistor R1 and the first end of the second resistor R2, the sampling point S includes a first sampling point S1 and a second sampling point S2, the first sampling point S1 is disposed between the second end of the first resistor R1 and the connector 15, and the second sampling point S2 is disposed between the first end of the second resistor R2 and the connector 15. The analog-to-digital conversion module 12 is connected to the first sampling point S1 and the second sampling point S2, the analog-to-digital conversion module 12 is configured to obtain a first sampling voltage V11 from the first sampling point S1, compare the first sampling voltage V11 with a reference voltage of the reference power Vref to obtain a first comparison result, obtain a first digital voltage signal corresponding to the first sampling point S1 according to the first comparison result, obtain a second sampling voltage V12 from the second sampling point S2, compare the second sampling voltage V12 with the reference voltage of the reference power Vref to obtain a second comparison result, and obtain a second digital voltage signal corresponding to the second sampling point S2 according to the second comparison result. The signal sampling circuit 10 may further comprise a second processor 16, the second processor 16 being arranged to determine the state of the connector 15 from the first digital voltage signal and the second digital voltage signal.

Since the voltage dividing module 11 and the analog-to-digital conversion module 12 are connected to the same reference power supply Vref in the embodiment of the present application, the actual voltages of the power supplies connected to the voltage dividing module 11 and the analog-to-digital conversion module are the same, and further, under the condition of including the voltage follower, the sampling precision of the signal sampling circuit 10 is higher, so that the precision of the determined first digital voltage signal and the second digital voltage signal is higher, and further, the precision of the determined state of the connector 15 is higher.

As an example, the analog-to-digital conversion module 12 may include a plurality of data channels such that the first sampling point S1 and the second sampling point S2 may be connected using different channels of one analog-to-digital conversion module 12.

As another example, the signal sampling circuit may also include two analog-to-digital conversion modules 12, where one analog-to-digital conversion module 12 is connected to the first sampling point S1 and the other analog-to-digital conversion module 12 is connected to the second sampling point S2.

For example, the connector 15 may be determined to be in a conductive state in a case where a difference between the first digital voltage signal and the second digital voltage signal is within a preset range, and the connector 15 may be determined to be in a disconnected state in a case where a difference between the first digital voltage signal and the second digital voltage signal is not within a preset range.

The second processor 16 may include a micro control unit (Microcontroller Unit, MCU).

High voltage interlock circuits in hybrid and all-electric vehicles may protect personnel during vehicle assembly, repair, maintenance, and operation. The high-voltage interlock circuit may be provided with a high-voltage interlock connector, and the state of the high-voltage interlock connector affects the connectivity and integrity of the high-voltage interlock circuit, so that it is necessary to improve the state detection accuracy of the high-voltage interlock connector.

In some alternative embodiments, the connector 15 in the example shown in fig. 6 may comprise a high voltage interlock connector. In this way, the accuracy of the determined state of the high-voltage interlock connector is high.

The hybrid power and the full electric automobile can be charged by using the charging gun, and the hybrid power and the full electric automobile can also be charged by using the discharging gun. With the development of technology, the types of charging guns/discharging guns are increasing. For example, different types of charging/discharging guns may incorporate resistors of different resistance values, such that different types of charging/discharging guns may support different operating currents. For example, the resistance of the built-in resistor of the charging gun may include 100 ohms, 220 ohms, 680 ohms, 1500 ohms, etc., and the resistance of the built-in resistor of the discharging gun may include 470 ohms, 1000 ohms, 2000 ohms, 2700 ohms, etc. The accurate identification of the operating current supported by the charge/discharge gun can be advantageous in avoiding the use of excessive current, so that it is very necessary to improve the accuracy of detection of the operating current.

In some alternative embodiments, as shown in fig. 7, the voltage dividing module 11 includes a first resistor R1 and a second resistor R2, where the first resistor R1 and the second resistor R2 are connected in series between the reference power Vref and the ground GND. The first end of the first resistor R1 is connected to the reference power Vref, the second end of the first resistor R1 is connected to the first end of the second resistor R2, and the second end of the second resistor R2 is connected to the ground GND. The second resistor R2 may be a built-in resistor of a charge gun or a discharge gun. The signal sampling circuit 10 may further comprise a third processor 17, the third processor 17 being operable to determine the operating current supported by the charging gun or the discharging gun from the digital voltage signal.

Since the voltage dividing module 11 and the analog-to-digital conversion module 12 are connected with the same reference power supply Vref in the embodiment of the application, the actual voltages of the power supplies connected with the voltage dividing module 11 and the analog-to-digital conversion module are the same, and further under the condition of including a voltage follower, the sampling precision of the signal sampling circuit 10 is higher, so that the precision of the determined digital voltage signal is higher, and further, the precision of the determined working current supported by the charging gun or the discharging gun is higher.

It can be understood that, when the built-in resistances of the charging gun or the discharging gun are different, that is, when the resistances of the second resistors R2 are different, the voltages of the sampling points S are also different, so that the voltages of the sampling points S can be used to determine the resistances of the second resistors R2, and the resistances of the second resistors R2 can be used to determine the operating current supported by the charging gun or the discharging gun.

The third processor 17 may comprise a micro control unit (Microcontroller Unit, MCU).

As described above, in addition, if a short circuit fault occurs in the external circuit corresponding to the voltage dividing module, or the first resistor or the second resistor is changed by the environmental change, the current of the voltage dividing module may increase.

In some alternative embodiments, as shown in fig. 8, the signal sampling circuit 10 may further include a unidirectional conduction module 18, where the unidirectional conduction module 18 and the first resistor R1 are connected in series between the reference power Vref and the sampling point S, and the unidirectional conduction module 18 is configured to prevent a current flowing through the sampling point S from flowing into the reference power Vref. In this way, the accuracy of the reference power Vref can be further ensured.

For example, in the case where the signal sampling circuit 10 includes the voltage follower 131, the unidirectional conduction module 18 and the first resistor R1 may be connected in series between the output terminal of the voltage follower 131 and the sampling point S.

For example, as shown in fig. 8, unidirectional conduction module 18 may include a unidirectional conduction diode D. For example, an anode of the unidirectional conduction diode D may be connected to the second end of the first resistor R1, and a cathode of the unidirectional conduction diode D may be connected to the sampling point S.

Of course, the unidirectional conduction diode D may also be disposed between the output end of the voltage follower 131 and the first end of the first resistor R1, where an anode of the unidirectional conduction diode D may be connected to the output end of the voltage follower 131, and a cathode of the unidirectional conduction diode D may be connected to the first end of the first resistor R1.

In some alternative embodiments, as shown in fig. 8, the signal sampling circuit 10 may further include a filtering module 19, where the filtering module 19 is connected to an input terminal of the analog-to-digital conversion module 12, and the input terminal of the analog-to-digital conversion module 12 may be used to filter out the interference signal. In this way, the sampling accuracy of the signal sampling circuit can be further improved.

For example, the filtering module 19 may include a filtering capacitor C, where one end of the filtering capacitor C is connected to the input end of the analog-to-digital conversion module 12, and the other end of the filtering capacitor C may be grounded GND.

Based on the same inventive concept, the embodiments of the present application also provide a battery management system, including the signal sampling circuit in any of the above embodiments. It can be appreciated that the battery management system has the beneficial effects of the signal sampling circuit provided in the embodiments of the present application, and specific descriptions of the signal sampling circuit in the above embodiments may be referred to, which is not repeated herein.

Based on the same inventive concept, the application also provides an electric device. The power utilization device comprises a battery management system comprising the signal sampling circuit of any of the above embodiments. It can be understood that the power consumption device has the beneficial effects of the signal sampling circuit provided in the embodiments of the present application, and specific descriptions of the signal sampling circuit in the above embodiments may be referred to, which is not repeated herein.

In the above embodiments, the resistor is represented by a single resistor. In other embodiments, the resistor may also be an integration of series, parallel, or series-parallel resistors. In the above embodiments, the capacitor is represented by a single capacitor. In other embodiments, the capacitor may also be an integration of series, parallel, or series-parallel capacitors. Specific parameters of each device can be set according to actual requirements, and the application is not limited to the specific parameters.

It should be noted that, in the case of no conflict, the embodiments and features in the embodiments may be combined with each other.

While the present application has been described with reference to a preferred embodiment, various modifications may be made and equivalents may be substituted for elements thereof without departing from the scope of the present application, and in particular, the technical features mentioned in the various embodiments may be combined in any manner as long as there is no structural conflict. The present application is not limited to the specific embodiments disclosed herein, but encompasses all technical solutions falling within the scope of the claims.

Claims

1. The signal sampling circuit is characterized by comprising a voltage division module and an analog-to-digital conversion module; wherein,

the voltage division module is connected with a reference power supply, and sampling points are arranged in the voltage division module;

the analog-to-digital conversion module is connected with the sampling point, and is used for acquiring sampling voltage from the sampling point, comparing the sampling voltage with the reference voltage of the reference power supply to obtain a comparison result, and obtaining a digital voltage signal corresponding to the sampling point according to the comparison result.

2. The signal sampling circuit of claim 1, wherein the voltage dividing module comprises a first resistor and a second resistor, a first end of the first resistor is connected to a reference power supply, a second end of the first resistor is connected to a first end of the second resistor, a second end of the second resistor is connected to ground, and a sampling point is provided between the second end of the first resistor and the first end of the second resistor.

3. The signal sampling circuit according to claim 1 or 2, wherein the signal sampling circuit further comprises an isolation protection module;

the voltage division module is connected with the reference power supply through the isolation protection module.

4. A signal sampling circuit according to claim 3, wherein the isolation protection module comprises a voltage follower, the non-inverting input of the voltage follower is connected to the reference power supply, the inverting input of the voltage follower is connected to the output of the voltage follower, and the output of the voltage follower is connected to the voltage dividing module.

5. The signal sampling circuit of claim 2, wherein the first resistor is a fixed resistor and the second resistor is a thermistor.

6. The signal sampling circuit of claim 5, wherein a distance between the second resistor and a single cell in the battery pack is less than a temperature sensing distance threshold;

7. The signal sampling circuit of claim 2, wherein a connector is connected between the first resistor and the second resistor, the sampling points comprising a first sampling point and a second sampling point, the first sampling point being disposed between the second end of the first resistor and the connector, the second sampling point being disposed between the first end of the second resistor and the connector;

the analog-to-digital conversion module is connected with the first sampling point and the second sampling point, and is used for obtaining a first sampling voltage from the first sampling point, comparing the first sampling voltage with the reference voltage of the reference power supply to obtain a first comparison result, obtaining a first digital voltage signal corresponding to the first sampling point according to the first comparison result, obtaining a second sampling voltage from the second sampling point, comparing the second sampling voltage with the reference voltage of the reference power supply to obtain a second comparison result, and obtaining a second digital voltage signal corresponding to the second sampling point according to the second comparison result;

8. The signal sampling circuit of claim 7, wherein the connector comprises a high voltage interlock connector.

9. The signal sampling circuit of claim 2, wherein the second resistor is a built-in resistor of a charge gun or a discharge gun;

the signal sampling circuit further comprises a third processor, wherein the third processor is used for determining working current supported by the charging gun or the discharging gun according to the digital voltage signal.

10. The signal sampling circuit of claim 2, further comprising a unidirectional conduction module, the unidirectional conduction module and the first resistor being connected in series between the reference power supply and the sampling point, the unidirectional conduction module being configured to prevent current flowing through the sampling point from flowing into the reference power supply;

and/or the signal sampling circuit further comprises a filtering module, wherein the filtering module is connected with the input end of the analog-to-digital conversion module and is used for filtering interference signals.

11. A battery management system comprising a signal sampling circuit as claimed in any one of claims 1 to 10.

12. An electrical consumer comprising the battery management system of claim 11.