Current detection module and battery pack system

Abstract

The utility model discloses a current detection module and a battery pack system. The current detection module comprises a current detector, a shunt resistor, a first / second resistor and a first high-voltage switch. The current detector comprises a first / second voltage detection pin and a first / second current detection pin; the shunt resistor is connected in series between the battery pack and the current detector, the first end of the shunt resistor is connected with the negative electrode of the battery pack and the first current detection pin, and the second end of the shunt resistor is connected with the second current detection pin, so that the current detector obtains the total loop current value of the battery pack; the first voltage detection pin is connected with the positive electrode of the battery pack through the first resistor, and the second voltage detection pin is connected with the negative electrode of the battery pack or the second end of the shunt resistor through the second resistor and the first high-voltage switch which are connected in series, so that the current detector obtains the total voltage of the battery pack. According to the invention, the cost of separate arrangement of high-voltage detection and current detection of an existing BMS system can be reduced, and the space of a battery pack system is reduced.

Description

Technical Field

[0001] The utility model relates to the field of battery pack detection, and in particular to a current detection module and a battery pack system. Background Art

[0002] With the development of science and technology, new energy vehicles are becoming more and more popular among consumers. As an important component of new energy vehicles, the performance of the battery pack system directly affects the overall quality of the vehicle. In order to ensure the safety of the power battery system of new energy vehicles, the current and voltage of the total circuit of the battery pack are generally collected, and the collected data is uploaded to the battery management system (BMS) in real time, so that the BMS system can closely monitor the operating status of the battery pack.

[0003] At present, the collection of the total loop current and total voltage of the battery pack is based on two different detection modules. Since the voltage detection and current detection are separately set in this method, the battery detection structure will be complicated, which will increase the occupied space and weight of the battery pack system, which is not conducive to the lightweight development of the battery. Utility Model Content

[0004] The purpose of the utility model is to solve the problem that the voltage detection and current detection of the existing battery pack are set separately, which makes the battery pack system occupy a large space. The utility model provides a current detection module and a battery pack system, which adds a voltage measurement function to the current detection module design to replace the HVSU high-voltage monitoring module in the current BMS system architecture, so as to achieve the purpose of smaller battery pack system space.

[0005] To solve the above technical problems, the embodiments of the present utility model disclose a current detection module and a battery pack system, wherein the current detection module comprises: a current detector, a shunt resistor, a first resistor, a second resistor and a first high-voltage switch;

[0006] The current detector includes a first voltage detection pin, a second voltage detection pin, a first current detection pin, and a second current detection pin;

[0007] The shunt resistor is connected in series between the battery pack and the current detector, the first end of the shunt resistor is connected to the negative electrode of the battery pack and the first current detection pin respectively, the second end of the shunt resistor is connected to the second current detection pin, and the current flowing through the shunt resistor flows into the current detector through the second current detection pin so that the current detector obtains the current value of the total loop current of the battery pack;

[0008] The first voltage detection pin is connected to the positive electrode of the battery pack through the first resistor, the second voltage detection pin is connected to the negative electrode of the battery pack or the second end of the shunt resistor through the second resistor and the first high-voltage switch connected in series, and the current detector obtains the total voltage of the battery pack based on the voltage input to the first voltage detection pin and the second voltage detection pin.

[0009] The above technical solution is adopted, a current sensor chip with both current detection and voltage detection functions is selected, and the peripheral circuit connecting the chip and the battery pack is reasonably designed to form a current detection module. By setting up the current detection module, voltage detection and current detection can be completed through current detection and peripheral circuits, without the need to add the original high-voltage detection module, achieving the effect of reducing the cost of the entire energy system and reducing the space of the battery pack system.

[0010] According to another specific embodiment of the utility model, the current detector also includes a third voltage detection pin, which is connected to the positive electrode of the battery pack through a third resistor and a second high-voltage switch connected in series to transmit the voltage of the positive electrode of the battery pack to the current detector.

[0011] Specifically, resistors with appropriate resistance values ​​can be selected according to actual needs to detect accurate voltage values, thereby improving the applicability of the current detection module.

[0012] According to another specific embodiment of the present invention, the current detector also includes a voltage processing unit, which is connected to the second voltage detection pin and the third voltage detection pin respectively, and is used to perform average processing on the voltages input to the second voltage detection pin and the third voltage detection pin.

[0013] By adopting the above technical solution, a more accurate voltage value can be obtained after being processed by the voltage processing unit.

[0014] According to another specific implementation of the present utility model, the current detection module further includes a fourth resistor, which is connected in series between one end of the third resistor used for connecting the third voltage detection pin and the ground line.

[0015] Similarly, resistors with appropriate resistance values ​​can be selected according to actual needs to detect accurate voltage values, thereby improving the applicability of the current detection module.

[0016] According to another specific embodiment of the utility model, the current detector includes:

[0017] A multiplexing unit has a plurality of input terminals, and the first voltage detection pin to the third voltage detection pin are respectively connected to the plurality of input terminals of the multiplexing unit;

[0018] A first sigma-delta modulator is connected to the output end of the multiplexing unit and is used to convert analog signals received at each input end of the multiplexing unit into digital signals and then output them;

[0019] A first digital sampling filter, connected to the output end of the first sigma-delta modulator, for removing a noise signal from the digital signal output by the first sigma-delta modulator;

[0020] The first low-pass filter is connected to the first digital sampling filter and is used to determine the total voltage value of the battery pack based on the signal output by the first digital sampling filter.

[0021] Specifically, the multiplexing unit, the first sigma-delta modulator, the first digital sampling filter and the first low-pass filter are connected in sequence, and the analog voltage is input from multiple input terminals of the multiplexing unit until the first low-pass filter outputs a voltage value.

[0022] According to another specific embodiment of the present utility model, the current detection module further includes:

[0023] a fifth resistor, connected in series between one end of the first resistor connected to the first voltage detection pin and the ground line;

[0024] The sixth resistor is connected in series between one end of the second resistor connected to the second voltage detection pin and the ground line.

[0025] According to another specific embodiment of the utility model, the current detector includes a communication pin for connecting to a CAN chip, so that the CAN chip is respectively connected to the current detection module and the battery pack management system, for realizing data transmission between the current detection module and the battery pack management system.

[0026] According to another specific embodiment of the present utility model, the current detector also includes a voltage analog signal output pin for connecting to a battery pack management system, so as to realize data transmission between the current detection module and the battery pack management system.

[0027] According to another specific embodiment of the present invention, the current detection module also includes a power supply unit, the power supply unit includes a voltage stabilizing circuit and a DC conversion circuit for voltage stabilization, the input end of the voltage stabilizing circuit is connected to the power supply, the output end of the voltage stabilizing circuit is connected to the input end of the DC conversion circuit, and the output end of the DC conversion circuit is connected to the power pin of the current detector; wherein the DC conversion circuit is used to convert the voltage output by the voltage stabilizing circuit into a preset output voltage and then output it to the power pin of the current detector. The embodiment of the present invention also discloses a battery pack system, including a battery pack, a battery pack management system, and the current detection module mentioned in any of the above embodiments, the current detection module is connected to the battery pack management system, and is used to output the acquired current value of the total loop of the battery pack and the total voltage value of the battery pack to the battery pack management system. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] Figure 1 A circuit structure diagram of a current detection module provided by a specific embodiment of the utility model is shown;

[0029] Figure 2 A schematic diagram showing a specific circuit structure of a voltage detection unit of a current detector provided by a specific embodiment of the utility model is shown;

[0030] Figure 3 A schematic diagram showing a specific circuit structure of a current detection part of a current detector provided by a specific embodiment of the utility model is shown;

[0031] Figure 4 A structural block diagram of a current detection module provided by a specific embodiment of the utility model is shown. DETAILED DESCRIPTION

[0032] The following is an explanation of the implementation of the present invention by specific specific embodiments. Those skilled in the art can easily understand other advantages and functions of the present invention from the contents disclosed in this specification. Although the description of the present invention will be introduced in conjunction with the preferred embodiment, this does not mean that the features of this utility model are limited to this implementation. On the contrary, the purpose of introducing the utility model in conjunction with the implementation is to cover other options or modifications that may be extended based on the claims of the present invention. In order to provide a deep understanding of the present invention, the following description will include many specific details. The present invention can also be implemented without using these details. In addition, in order to avoid confusion or blurring the focus of the present invention, some specific details will be omitted in the description. It should be noted that, in the absence of conflict, the embodiments in the present invention and the features in the embodiments can be combined with each other.

[0033] It should be noted that in this specification, similar reference numerals and letters denote similar items in the following drawings, and therefore, once an item is defined in one drawing, it does not need to be further defined and explained in the subsequent drawings.

[0034] The terms “first”, “second”, etc. are only used for distinguishing descriptions and should not be understood as indicating or implying relative importance.

[0035] In order to make the purpose, technical solution and advantages of the present invention more clear, the implementation mode of the present invention will be further described in detail below with reference to the accompanying drawings.

[0036] In one embodiment of the present application, a current sensing module (Current Sensing Module, CSM) and an HVSU high-voltage detection module are used to detect the current and total voltage of the total loop of the battery pack, respectively. Specifically, both the CSM and the high-voltage detection module are connected to the BMS system. Among them, the CSM is used to measure the total loop current of the power battery pack. The CSM is connected in series between the positive and negative poles of the battery pack through a shunt to obtain the current passing through the shunt, and then send it to the BMS system through the CAN bus. The detection of the battery pack voltage is achieved through the HVSU high-voltage detection module. However, in this method, high-voltage detection and current detection are also separately set, and there are still problems of high battery cost and large volume space.

[0037] Based on this, another embodiment of the present invention provides a current detection module, referring to Figure 1 As shown, the current detection module includes a current detector 1, a shunt resistor R0, a first resistor R1, a second resistor R2 and a first high-voltage switch K1.

[0038] The current detector 1 includes a first voltage detection pin V1 , a second voltage detection pin V2 , a first current detection pin I1 , and a second current detection pin I2 .

[0039] In specific implementation, the shunt resistor R0 is connected in series between the battery pack 2 and the current detector 1, the first end of the shunt resistor R0 is connected to the negative electrode of the battery pack 2 and the first current detection pin I1 respectively, the second end of the shunt resistor R0 is connected to the second current detection pin I2, and the current flowing through the shunt resistor R0 flows into the current detector 1 through the second current detection pin I2, so that the current detector 1 obtains the current value of the total loop current of the battery pack. Specifically, the first current detection pin I1 and the first end of the shunt resistor R0 can be connected to the shell of the vehicle body where the battery pack 2 is located, so as to achieve the purpose of connecting to the ground wire.

[0040] The first voltage detection pin V1 is connected to the positive electrode of the battery pack through the first resistor R1, and the second voltage detection pin V2 is connected to the negative electrode of the battery pack 2 or the second end of the shunt resistor R0 through the second resistor R2 and the first high-voltage switch K1 connected in series. The current detector 1 obtains the total voltage of the battery pack 2 based on the voltage input by the first voltage detection pin V1 and the second voltage detection pin V2. Specifically, when the BMS system wants to obtain the current value of the total loop current of the battery pack 2 and / or the total voltage value of the battery pack 2, the current detector 1 and the peripheral circuits connected to its corresponding pins will complete the current and / or voltage acquisition processing, without the need to add an additional circuit for measuring voltage, thereby reducing costs and battery pack space.

[0041] Exemplarily, the current detector 1 also includes a third voltage detection pin V3, which is connected to the positive electrode of the battery pack through a third resistor R3 and a second high-voltage switch K2 connected in series, so as to transmit the voltage of the positive electrode of the battery pack 2 to the current detector 1.

[0042] That is, the current detection module of the present application can be connected to the positive electrode of the battery pack through the first voltage detection pin V1 and the third voltage detection pin V3 respectively. When obtaining the total voltage of the battery pack, the total voltage of the battery pack can be obtained through the data of the first voltage detection pin V1 and the second voltage detection pin V2, or the total voltage of the battery pack can be obtained through the data of the third voltage detection pin V3 and the second voltage detection pin V2, or the total voltage of the battery pack can be obtained through the data of the first voltage detection pin V1, the second voltage detection pin V2 and the third voltage detection pin V3.

[0043] This approach can avoid the problem of failure to collect voltage or inaccurate collection due to failure of the first voltage detection pin V1 or the third voltage detection pin V3, thereby improving the reliability of the current detection module and the accuracy of collection.

[0044] Exemplarily, the current detector 3 further includes a voltage processing unit connected to the second voltage detection pin V2 and the third voltage detection pin V3 respectively, and configured to perform mean value processing on the voltages inputted from the second voltage detection pin V2 and the third voltage detection pin V3.

[0045] Specifically, in order to more accurately collect the voltages of the positive and negative electrodes of the battery pack, the current detection module further includes a fourth resistor R4, a fifth resistor R5, and a sixth resistor R6.

[0046] The fourth resistor R4 is connected in series between one end of the third resistor R3 connected to the third voltage detection pin V3 and the ground line.

[0047] The fifth resistor R5 is connected in series between one end of the first resistor R1 connected to the first voltage detection pin V1 and the ground line;

[0048] The sixth resistor R6 is connected in series between one end of the second resistor R2 connected to the second voltage detection pin V2 and the ground line.

[0049] Specifically, the resistors can be selected to have appropriate resistance values ​​according to actual needs to detect accurate voltage values, thereby improving the applicability of the current detection module.

[0050] Furthermore, the current detector 1 includes a voltage detection unit for detecting the total voltage of the battery pack 2 and a current detection unit for detecting the total loop current of the battery pack 2 .

[0051] For example, Figure 2 As shown, the voltage detection unit includes a multiplexing unit 101 , a first sigma-delta modulator 102 , a first distortion compensation circuit 103 , a first digital sampling filter 104 , and a first low-pass filter 105 .

[0052] Among them, the multiplexing unit 101 has multiple input terminals, and the first voltage detection pin V1 to the third voltage detection pin V3 are respectively connected to the multiple input terminals of the multiplexing unit. The first sigma-delta modulator 102 is connected to the output terminal of the multiplexing unit 101, and is used to convert the analog signals received by each input terminal of the multiplexing unit into digital signals and then output them to the input terminal of the first distortion compensation circuit 103. The first digital sampling filter 104 is connected to the output terminal of the first distortion compensation circuit 103, and is used to remove the noise signal in the digital signal output by the first distortion compensation circuit 103. The first low-pass filter 105 is connected to the first digital sampling filter 104, and is used to determine the total voltage value of the battery pack based on the signal output by the first digital sampling filter 104.

[0053] Specifically, the multiplexing unit 101, the first sigma-delta modulator 102, the first digital sampling filter 103, the first distortion compensation circuit 104 and the first low-pass filter 105 are connected in sequence, and the analog voltage is input from multiple input terminals of the multiplexing unit 101 until the first low-pass filter 105 outputs a voltage value.

[0054] For example, Figure 3 As shown, the current detection unit includes an electrostatic protection circuit 106, a gain amplifier circuit 107, a second sigma-delta modulator 108, a second distortion compensation circuit 109, a second digital sampling filter 110, and a second low-pass filter 111 connected in sequence, wherein the electrostatic protection circuit 106 is connected to both ends of the group resistor R0.

[0055] Specifically, in this embodiment, the output ends of the first current detection pin I1 and the second current detection pin I2 are connected to the input end of the electrostatic protection circuit 106, the output end of the electrostatic protection circuit 106 is connected to the input end of the gain amplifier circuit 107, the output end of the gain amplifier circuit 107 is connected to the input end of the second sigma-delta modulator 108, the second sigma-delta modulator 108 performs analog-to-digital conversion on the output signal, and passes through the second distortion compensation circuit 109, the second digital sampling filter 110 and the second low-pass filter 111 in sequence to output the current value in the total loop of the battery pack 2 to the BMS system through the CAN chip 3.

[0056] Furthermore, the current detection unit collects the voltage across the shunt resistor R0 by connecting the first current detection pin I1 and the second current detection pin I2 to the two ends of the shunt resistor R0, and calculates the detected current according to the collected voltage.

[0057] Specifically, if Figure 4 As shown, the current detector 1 also includes a communication pin CAN for connecting to the CAN chip 5, so that the CAN chip 5 is connected to the current detection module and the battery pack management system respectively, for realizing data transmission between the current detection module and the battery pack management system. Alternatively, the current detector also includes a voltage analog signal output pin for connecting to the battery pack management system, for realizing data transmission between the current detection module and the battery pack management system.

[0058] The current detection module also includes a power supply unit 6, which includes a voltage stabilizing circuit 4 and a DC conversion circuit 3 for voltage stabilization. The input end of the voltage stabilizing circuit 4 is connected to the power supply, the output end of the voltage stabilizing circuit 4 is connected to the input end of the DC conversion circuit 3, and the output end of the DC conversion circuit 3 is connected to the power pin of the current detector 1. Specifically, the voltage stabilizing circuit 4 can be connected to a 12V power supply (i.e. Figure 4 The Power Supply 1) is used to convert the 12V voltage into a 5V voltage for output; the DC conversion circuit 3 is used to convert the voltage output by the voltage stabilizing circuit 4 into an output preset voltage.

[0059] Based on the same concept, the utility model also provides a battery pack system, including a battery pack, a battery pack management system and a current detection module provided in the above embodiments. The current detection module can be connected to the battery pack management system to output the acquired current value of the total circuit of the battery pack and the total voltage value of the battery pack to the battery pack management system.

[0060] In the accompanying drawings, some structural or method features may be shown in a specific arrangement and / or order. However, it should be understood that such a specific arrangement and / or order may not be required. Instead, in some embodiments, these features may be arranged in a manner and / or order different from that shown in the illustrative drawings. In addition, the inclusion of structural or method features in a particular figure does not mean that such features are required in all embodiments, and in some embodiments, these features may not be included or may be combined with other features.

[0061] It should be noted that the units / modules mentioned in the various device embodiments of the present utility model are all logical units / modules. Physically, a logical unit / module can be a physical unit / module, or a part of a physical unit / module, or can be implemented as a combination of multiple physical units / modules. The physical implementation of these logical units / modules themselves is not the most important. The combination of functions implemented by these logical units / modules is the key to solving the technical problems proposed by this application. In addition, in order to highlight the innovative part of this application, the above-mentioned device embodiments of the present utility model do not introduce units / modules that are not closely related to solving the technical problems proposed by the present utility model, which does not mean that there are no other units / modules in the above-mentioned device embodiments.

[0062] It should be noted that, in the examples and description of the present utility model, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device. In the absence of further restrictions, the elements defined by the statement "comprise one" do not exclude the presence of other identical elements in the process, method, article or device including the elements.

[0063] Although the present invention has been illustrated and described with reference to certain preferred embodiments of the present invention, it should be understood by those skilled in the art that the above contents are further detailed descriptions of the present invention in combination with specific embodiments, and it cannot be determined that the specific implementation of the present invention is limited to these descriptions. Those skilled in the art may make various changes in form and details, including making several simple deductions or substitutions, without departing from the spirit and scope of the present invention.

Claims

1. A current detection module for a battery pack, characterized in that: include: A current detector, a shunt resistor, a first resistor, a second resistor and a first high-voltage switch; The current detector comprises a first voltage detection pin, a second voltage detection pin, a first current detection pin and a second current detection pin; The shunt resistor is connected in series between the battery pack and the current detector, the first end of the shunt resistor is connected to the negative electrode of the battery pack and the first current detection pin respectively, the second end of the shunt resistor is connected to the second current detection pin, and the current flowing through the shunt resistor flows into the current detector through the second current detection pin so that the current detector obtains the current value of the total loop current of the battery pack; The first voltage detection pin is connected to the positive electrode of the battery pack through the first resistor, the second voltage detection pin is connected to the negative electrode of the battery pack or the second end of the shunt resistor through the second resistor and the first high-voltage switch connected in series, and the current detector obtains the total voltage of the battery pack based on the voltage input to the first voltage detection pin and the second voltage detection pin.

2. The current detection module according to claim 1, characterized in that: The current detector also includes a third voltage detection pin, which is connected to the positive electrode of the battery pack through a third resistor and a second high-voltage switch connected in series, so as to transmit the voltage of the positive electrode of the battery pack to the current detector.

3. The current detection module according to claim 2, characterized in that: The current detector further includes a voltage processing unit connected to the second voltage detection pin and the third voltage detection pin respectively, and configured to perform average processing on the voltages input to the second voltage detection pin and the third voltage detection pin.

4. The current detection module according to claim 2, characterized in that: A fourth resistor is also included, and the fourth resistor is connected in series between one end of the third resistor connected to the third voltage detection pin and the ground line.

5. The current detection module according to claim 2, characterized in that: The current detector comprises: A multiplexing unit has a plurality of input terminals, wherein the first voltage detection pin to the third voltage detection pin are respectively connected to the plurality of input terminals of the multiplexing unit; A first sigma-delta modulator, connected to the output end of the multiplexing unit, for converting analog signals received at each input end of the multiplexing unit into digital signals and outputting the digital signals; a first digital sampling filter, connected to an output end of the first sigma-delta modulator, and used for removing a noise signal from the digital signal output by the first sigma-delta modulator; The first low-pass filter is connected to the first digital sampling filter and is used to determine the total voltage value of the battery pack based on the signal output by the first digital sampling filter.

6. The current detection module according to claim 1, characterized in that: Also includes: a fifth resistor, connected in series between one end of the first resistor connected to the first voltage detection pin and a ground line; A sixth resistor is connected in series between one end of the second resistor connected to the second voltage detection pin and the ground line.

7. The current detection module according to claim 1, characterized in that: The current detector includes a communication pin for connecting to a CAN chip, so that the CAN chip is connected to the current detection module and the battery pack management system respectively, so as to realize data transmission between the current detection module and the battery pack management system.

8. The current detection module according to claim 1, characterized in that: The current detector also includes a voltage analog signal output pin for connecting to a battery pack management system, so as to realize data transmission between the current detection module and the battery pack management system.

9. The current detection module according to claim 1, characterized in that: It also includes a power supply unit, the power supply unit includes a voltage stabilizing circuit and a DC conversion circuit for voltage stabilization, the input end of the voltage stabilizing circuit is connected to a power supply, the output end of the voltage stabilizing circuit is connected to the input end of the DC conversion circuit, and the output end of the DC conversion circuit is connected to the power pin of the current detector; Wherein, the DC conversion circuit is used to convert the voltage output by the voltage stabilization circuit into a preset voltage and then output it to the power pin of the current detector.

10. A battery pack system, characterized in that: It includes a battery pack, a battery pack management system and a current detection module as described in any one of claims 1 to 9, wherein the current detection module is connected to the battery pack and the battery pack management system, respectively, and is used to output the acquired current value of the battery pack total circuit and the total voltage value of the battery pack to the battery pack management system.

Images