BMS temperature acquisition circuit and battery pack
By designing battery modules, temperature acquisition modules, control circuit modules and AFE acquisition chip modules in the BMS temperature acquisition circuit, the problems of reduced acquisition accuracy and large power consumption in the prior art are solved, and higher acquisition accuracy and lower power consumption are achieved.
Patent Information
- Application Number
- CN202422003638.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-08-16
- Publication Date
- 2025-06-06
- Estimated Expiration
- 2034-08-16
AI Technical Summary
The existing BMS temperature acquisition circuit has problems such as reduced acquisition accuracy and large power consumption, especially when the temperature acquisition points are dense, resulting in unstable energy supply of AFE chips, reduced performance, reduced acquisition accuracy, increased power consumption, and even the risk of battery pack scrapping.
A BMS temperature acquisition circuit is designed, including a battery module, a temperature acquisition module, a control circuit module and an AFE acquisition chip module. By setting a pull-up resistor at the signal output end of the control unit, the temperature sensor does not need to set a pull-up resistor, which effectively reduces the number of resistors, reduces power consumption, and improves the acquisition accuracy.
This design effectively reduces the number of resistors, improves PCB utilization, reduces power consumption, reduces voltage errors of each temperature sensor, improves acquisition accuracy, and reduces the standby power consumption and stable performance of the battery pack and the reference voltage.
Smart Images
Figure CN222951867U_ABST
Abstract
Description
Technical Field
[0001] The utility model belongs to the technical field of electronic circuits, and in particular relates to a BMS temperature acquisition circuit and a battery pack. Background Art
[0002] The temperature acquisition circuit and method of the battery cells in the series battery PACK (battery PACK generally refers to the combined battery) are applied to the multi-channel temperature acquisition solution of the new energy battery management BMS (BATTERY MANAGEMENT SYSTEM). With the increase of the energy density of lithium batteries, the change of lithium battery temperature greatly affects its performance, so it is more and more important to know the temperature of the lithium battery cell itself. Especially for large-scale energy storage, the consistency of battery temperature directly affects the battery life, working status and system economy, and even affects the system safety in severe cases. Therefore, it is necessary to strictly manage and monitor the battery temperature to avoid the occurrence of systemic risks.
[0003] The temperature acquisition of existing battery systems usually uses batteries to power the front-end AFE (Analog Front End), and the AFE chip provides a reference voltage to provide power to multiple strings of NTCs (negative temperature coefficient thermistors), such as Figure 1 As shown in the figure, n-channel NTC temperature acquisition requires n-channel pull-up resistors. However, due to the dense temperature acquisition points, the AFE chip power supply is unstable, resulting in performance degradation, reduced acquisition accuracy, increased power consumption, and inaccurate single-cell voltage and temperature acquisition in severe cases, leaving great risks and hidden dangers; and due to the increase in temperature detection points, the supply current of the battery PACK is bound to increase, and the risk of battery over-discharge caused by long-term standby increases, and in severe cases, the battery pack may even be scrapped, increasing the loss.
[0004] AFE (Analog Front End, analog front end, which includes sensor interface, analog signal conditioning (including impedance transformation, programmable gain amplification, filtering and polarity conversion, etc.) circuit, analog multiplexer, sample and hold, ADC, data cache and control logic and other components. In BMS, the role of AFE is to realize battery information collection, status monitoring and other functions. It measures the voltage of each battery cell in the battery stack and sets it to the MCU to monitor the status of the battery pack, such as the battery voltage, current and temperature. At the same time, AFE can also be used to measure the BMS board temperature through the built-in temperature sensor. Utility Model Content
[0005] The embodiment of the utility model provides a BMS temperature acquisition circuit, aiming to solve the problems of reduced acquisition accuracy and high power consumption in the existing BMS temperature acquisition circuit.
[0006] The embodiment of the utility model is implemented as follows: a BMS temperature acquisition circuit includes a battery module, a temperature acquisition module, a control circuit module and an AFE acquisition chip module;
[0007] The battery module includes a plurality of battery cells connected in series;
[0008] The temperature acquisition module includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell;
[0009] The control circuit module includes at least one control unit, and a signal input end of the control unit is connected to N temperature sensors, wherein N is greater than or equal to 1;
[0010] The signal control terminal of the control unit is connected to the AFE acquisition chip module, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module;
[0011] The signal output terminal of the control unit is connected to the reference voltage terminal through a pull-up resistor, and the signal output terminal of the control unit is also connected to the AFE acquisition chip module, which is used to output the collected information to the controller through the AFE acquisition chip module.
[0012] Furthermore, two ends of the temperature sensor are connected to the corresponding control unit through any one of a wiring harness, a PCB and an FPC.
[0013] Furthermore, the temperature sensor is fixed near the pole of the battery cell or at a location where heat is generated.
[0014] Furthermore, the temperature sensor is an NTC.
[0015] Further, the temperature sensor is connected in parallel with the first capacitor.
[0016] Furthermore, the signal output end of the control unit is connected to one end of the first resistor, the other end of the first resistor is connected to the AFE acquisition chip module, the other end of the first resistor is also grounded through the second capacitor, and the first resistor and the second capacitor form a low-pass filter circuit.
[0017] Furthermore, the reference voltage terminal is connected to the reference voltage of the AFE acquisition chip module or to an external reference voltage.
[0018] Furthermore, the control unit includes any one of a multiplexer or a multi-way analog switch.
[0019] Furthermore, the AFE acquisition chip module is connected to the controller via ISOSPI or a daisy chain.
[0020] In a second aspect, the present application also provides a battery pack, comprising the BMS temperature acquisition circuit as described above.
[0021] The beneficial effect of the present application is that the BMS temperature acquisition circuit of the present application includes a battery module, a temperature acquisition module, a control circuit module and an AFE acquisition chip module, wherein the battery module includes a plurality of battery cells connected in series, the temperature acquisition module includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell, the control circuit module includes at least one control unit, the signal input end of the control unit is connected to the first end of N temperature sensors, wherein N is greater than or equal to 1, the signal control end of the control unit is connected to the AFE acquisition chip module, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module, the signal output end of the control unit is connected to the reference voltage end through a pull-up resistor, and the signal output end of the control unit is also connected to the AFE acquisition chip module, and is used to output the acquisition information to the controller through the AFE acquisition chip module. Through the above-mentioned setting, only a pull-up resistor needs to be set at the signal output end of the control unit, and the temperature sensor does not need to be set with a pull-up resistor, which effectively reduces the number of resistors and greatly increases the PCB utilization rate. At the same time, since N temperature sensors share a pull-up resistor, the power consumption is reduced, the voltage error of each temperature sensor is reduced, and the acquisition accuracy is improved. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 It is a circuit structure diagram of a BMS temperature acquisition circuit in the prior art;
[0023] Figure 2 This is a schematic diagram of the module structure of an embodiment of a BMS temperature acquisition circuit provided by the present application;
[0024] Figure 3 This is a circuit structure diagram of an embodiment of a BMS temperature acquisition circuit provided by the present application;
[0025] Figure 4 It is a circuit structure diagram of another embodiment of the BMS temperature acquisition circuit provided in the present application. DETAILED DESCRIPTION
[0026] In order to make the purpose, technical solution and advantages of the utility model clearer, the utility model is further described in detail below in conjunction with the accompanying drawings and embodiments. Examples of embodiments are shown in the accompanying drawings, in which the same or similar reference numerals throughout represent the same or similar elements or elements with the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the utility model, and cannot be understood as limiting the utility model. In addition, it should be understood that the specific embodiments described herein are only used to explain the utility model and are not used to limit the utility model.
[0027] In the description of the present invention, it should be understood that the terms "length", "width", "up", "down", "left", "right", "horizontal", "top", "bottom", etc. indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, they should not be understood as limitations on the present invention.
[0028] In addition, the terms "first" and "second" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, the features defined as "first" and "second" may explicitly or implicitly include one or more features. In the description of the present utility model, the meaning of "plurality" is two or more, unless otherwise clearly and specifically defined.
[0029] In the description of the present utility model, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection, or mutual communication; it can be a direct connection, or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present utility model can be understood according to specific circumstances.
[0030] In the present utility model, unless otherwise clearly specified and limited, a first feature being "above" or "below" a second feature may include that the first and second features are in direct contact, or may include that the first and second features are not in direct contact but are in contact through another feature between them. Moreover, a first feature being "above", "above" and "above" a second feature includes that the first feature is directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. A first feature being "below", "below" and "below" a second feature includes that the first feature is directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.
[0031] The disclosure below provides many different embodiments or examples for realizing different structures of the utility model. In order to simplify the disclosure of the utility model, the components and settings of specific examples are described below. Of course, they are only examples, and the purpose is not to limit the utility model. In addition, the utility model can repeat reference numbers and / or reference letters in different examples, and this repetition is for the purpose of simplification and clarity, and does not indicate the relationship between the various embodiments and / or settings discussed in itself. In addition, the utility model provides various specific examples of processes and materials, but those of ordinary skill in the art can be aware of the application of other processes and / or the use of other materials.
[0032] The BMS temperature acquisition circuit of the present application includes a battery module, a temperature acquisition module, a control circuit module and an AFE acquisition chip module, wherein the battery module includes a plurality of battery cells connected in series, the temperature acquisition module includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell, the control circuit module includes at least one control unit, the signal input end of the control unit is connected to the first end of N temperature sensors, wherein N is greater than or equal to 1, the signal control end of the control unit is connected to the AFE acquisition chip module, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module, the signal output end of the control unit is connected to the reference voltage end through a pull-up resistor, and the signal output end of the control unit is also connected to the AFE acquisition chip module, and is used to output the acquisition information to the controller through the AFE acquisition chip module. Through the above-mentioned setting, only a pull-up resistor needs to be set at the signal output end of the control unit, and the temperature sensor does not need to be set with a pull-up resistor, which effectively reduces the number of resistors and greatly increases the utilization rate of the PCB. At the same time, since the N-way temperature sensors share a pull-up resistor, the power consumption is reduced, the voltage error of each temperature sensor is reduced, and the acquisition accuracy is improved.
[0033] Embodiment 1
[0034] like Figures 2 to 4As shown, an embodiment of the present application provides a BMS temperature acquisition circuit, including a battery module 100, a temperature acquisition module 200, a control circuit module 300 and an AFE acquisition chip module 400;
[0035] The battery module 100 includes a plurality of battery cells connected in series;
[0036] The temperature acquisition module 200 includes a plurality of temperature acquisition units corresponding to a plurality of battery cells one by one, and the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on a battery pole of the corresponding battery cell;
[0037] The control circuit module 300 includes at least one control unit, and a signal input terminal of the control unit is connected to N temperature sensors, wherein N is greater than or equal to 1;
[0038] The signal control terminal of the control unit is connected to the AFE acquisition chip module 400, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module 400;
[0039] The signal output terminal of the control unit is connected to the reference voltage terminal Vref through the pull-up resistor RA, and the signal output terminal of the control unit is also connected to the AFE acquisition chip module 400 for outputting the acquired information to the controller 500 through the AFE acquisition chip module 400.
[0040] In implementation, the battery unit may be a battery monomer, in which case the battery module 100 is composed of a plurality of battery monomers connected in series. Alternatively, the battery unit may also be a whole composed of a plurality of battery monomers connected in parallel, and then the battery units are connected in series to form the battery module 100. In this case, the battery module 100 is composed of a plurality of battery monomers connected in parallel first and then in series, without limitation.
[0041] Each temperature acquisition unit corresponds to a battery cell, wherein the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell, and the battery pole refers to the positive connection terminal or the negative connection terminal of the battery cell. For example, the temperature sensor is arranged on the positive connection terminal of the corresponding battery cell, or the temperature sensor is arranged on the negative connection terminal of the corresponding battery cell to detect the temperature of the positive connection terminal or the negative connection terminal.
[0042] Optionally, the temperature sensor may be an NTC or other temperature detection element, without limitation.
[0043] Exemplarily, taking three battery cells as an example, the temperature acquisition module 200 includes three temperature acquisition units, and the three battery cells are respectively connected to the three temperature acquisition units. Optionally, taking 12 battery cells as an example, the temperature acquisition module 200 includes 12 temperature acquisition units, and the 12 battery cells are respectively connected to the 12 temperature acquisition units. Optionally, taking 30 battery cells as an example, the temperature acquisition module 200 includes 30 temperature acquisition units, and the 30 battery cells are respectively connected to the 30 temperature acquisition units.
[0044] It should be noted that the number of the above-mentioned battery cells and temperature acquisition units is an example of the embodiments of the present application, and is not a specific limitation of the present application. In some other embodiments, the battery cells and temperature acquisition units can also be set to other numbers, such as 15, 20, 25 or 35, etc., without limitation.
[0045] In some embodiments, the temperature sensor is installed in the battery pack and in contact with the battery pole. The temperature sensor is fixed near the battery pole of the battery cell or at a heat-generating position, which can better detect the temperature of the battery cell and improve the detection accuracy.
[0046] Optionally, the temperature sensor is connected in parallel with the first capacitor, and the temperature sensor and the capacitor in parallel can be used to implement some temperature control and temperature protection functions.
[0047] In implementation, the control circuit module 300 includes at least one control unit, each of which can be connected to N temperature sensors, for example, both ends of the temperature sensor are connected to the corresponding control unit through any one of a wiring harness, a PCB and an FPC. Exemplarily, the N temperature sensors are NTC1, NTC2, NTC3, ..., NTCn, wherein the first ends of NTC1, NTC2, NTC3, ..., NTCn are connected to the control circuit module 300 through T1, T2, T3, ..., Tn, respectively. Figure 3 shown.
[0048] Optionally, the control unit may adopt any one of a multiplexer or a multiplexer analog switch, without limitation.
[0049] For example, taking the control unit using the TPW4051 chip as an example, the TPW4051 chip has 8 inputs, then one control unit can be connected to 8 temperature sensors. When the number of temperature sensors is less than or equal to 8, only one control unit is required. Similarly, when the number of temperature sensors is more than 8 and less than or equal to 16, only 2 control units are required, and when the number of temperature sensors is more than 16 and less than or equal to 24, only 3 control units are required, and so on, without limitation.
[0050] It should be noted that the above-mentioned control unit uses the TPW4051 chip as an example of the embodiment of the present application, rather than a specific limitation of the present application. In some other embodiments, the control unit may also use other components that can realize the function of a multiplexer or an analog switch without limitation.
[0051] In some embodiments, Figure 4 As shown, the control circuit module 300 includes three control units, each control unit corresponds to a TPW4051 chip, and the signal input terminals of each TPW4051 chip are A0, A1, A2, A3, A4, A5, A6 and A7, wherein the first TPW4051 chip is U1, and the signal input terminals A0, A1, A2, A3, A4, A5, A6 and A7 of U1 are connected to the first terminals of NFC1, NFC2, NFC3, NFC4, NFC5, NFC6, NFC7 and NFC8 of the first row through T1, T2, T3, T4, T5, T6, T7 and T8 respectively. Similarly, the second TPW4051 chip is U2, and the signal input terminals A0, A1, A2, A3, A4, A5, A6 and A7 of U2 are connected to the first terminals of NFC1, NFC2, NFC3, NFC4, NFC5, NFC6, NFC7 and NFC8 in the second row through T9, T10, T11, T12, T13, T14, T15 and T16 respectively. The third TPW4051 chip is U3, and the signal input terminals A0, A1, A2, A3, A4, A5, A6 and A7 of U3 are connected to the first terminals of NFC1, NFC2, NFC3, NFC4, NFC5, NFC6, NFC7 and NFC8 in the third row through T17, T18, T19, T20, T21, T22, T23 and T24 respectively.
[0052] The signal control terminal of the control unit includes S0, S1, S2 and enable E terminal. After the S0, S1, S2 and enable E terminal of at least one control unit are connected to each other, they are connected to the GPIO port of the AFE acquisition chip module 400 for selecting the signal reading of the temperature sensor.
[0053] The output end of the AFE acquisition chip module 400 is connected to the controller 500, the signal output end A of the control unit is connected to the reference voltage end Vref through the pull-up resistor RA, and the signal output end of the control unit is also connected to the GPIO port of the AFE acquisition chip module 400, so that the AFE acquisition chip module 400 outputs the collected information to the controller 500.
[0054] The control unit includes any one of a multiplexer or a multiplexer analog switch, without limitation.
[0055] The temperature sensor is connected in parallel with the first capacitor, for example, the temperature sensor NTC1 is connected in parallel with the first capacitor C1, the temperature sensor NTC2 is connected in parallel with the first capacitor C2, and so on, the temperature sensor NTC8 is connected in parallel with the first capacitor C8, which will not be described in detail.
[0056] During implementation, the output pin (signal output terminal A) of the control unit is pulled up by a resistor to the reference voltage terminal Vref, and the output pin of the control unit is simultaneously connected to the GPIO port of the acquisition circuit AFE chip to read the voltage value of the n-channel temperature sensor. Optionally, the reference voltage terminal Vref is connected to the reference voltage of the AFE acquisition chip module 400 or to an external reference voltage, that is, the reference voltage can be provided by the AFE acquisition chip module 400 or by an external reference voltage, without limitation.
[0057] The BMS temperature acquisition circuit of the present application includes a battery module 100, a temperature acquisition module 200, a control circuit module 300 and an AFE acquisition chip module 400, wherein the battery module 100 includes a plurality of battery cells connected in series, the temperature acquisition module 200 includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell, the control circuit module 300 includes at least one control unit, the signal input end of the control unit is connected to N temperature sensors, wherein N is greater than or equal to 1, the signal control end of the control unit is connected to the AFE acquisition chip module 400, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module 400, the signal output end of the control unit is connected to the reference voltage end Vref through the pull-up resistor RA, and the signal output end of the control unit is also connected to the AFE acquisition chip module 400, and is used to output the acquisition information to the controller 500 through the AFE acquisition chip module 400. Through the above settings, it is only necessary to set a pull-up resistor RA at the signal output end of the control unit, while the temperature sensor does not need to set a pull-up resistor RA, which effectively reduces the number of resistors and greatly increases the PCB utilization rate. At the same time, since N temperature sensors share one pull-up resistor RA, power consumption is reduced, the voltage error of each temperature sensor is reduced, and the acquisition accuracy is improved.
[0058] In some optional embodiments, a low-pass filter circuit is further arranged between the control unit and the AFE acquisition chip module 400, and the low-pass filter circuit includes: a first resistor RB and a second capacitor CP, the signal output end of the control unit is connected to one end of the first resistor RB, the other end of the first resistor RB is connected to the AFE acquisition chip module 400, and the other end of the first resistor RB is also grounded through the second capacitor CP. The low-pass filter circuit is used to filter the high-frequency signal from the battery unit to improve the detection accuracy.
[0059] In some optional embodiments, the AFE acquisition chip module 400 and the controller 500 are connected by an isolated communication 600. For example, the AFE acquisition chip module 400 is connected to the controller 500 via ISOSPI or daisy chain. ISOSPI is isolated SPI (Serial Peripheral interface). Daisy chain is a connection technology in which multiple devices are connected together through a simple serial connection to form a chain structure.
[0060] Taking the temperature sensor as NTC as an example, the acquisition process and working mode of the NTC temperature sensor of the BMS temperature acquisition circuit embodiment provided by this application are as follows:
[0061] The n-channel NTC temperature sensors are connected to the control circuit module 300 in an n / 8 configuration. Each 8-channel NTC temperature sensor is connected to the corresponding A0-A7 input interface of TPW4051. The S0, S1, S2 and enable E pins of TPW4051 are connected to the GPIO port of the AFE acquisition chip to control the state of TPW4051. The TPW4051 is turned on by enabling the E pin, and the voltage acquisition value of the NTC temperature sensor is read by controlling the addresses of S0, S1 and S2.
[0062] When the E pin is enabled at a low level, the voltage at the reference voltage terminal Vref is connected to one of the NTC temperature sensors through the pull-up resistor RA. After resistor voltage division, the voltage is low-frequency filtered by the pull-up resistor RA, the first resistor RB and the second capacitor CP, and then connected to the GPIO port of the AFE acquisition chip.
[0063] The control addresses S0, S1, S2 and enable E pins of multiple multiplexers (analog switches) are connected in parallel, and the AFE acquisition chip can read n / 8 multi-channel temperature acquisition signals at the same time.
[0064] Compared with the traditional BMS temperature acquisition circuit, the control circuit module 300 of the present application adopts an 8-way multiplexer or analog switch, which reduces n-1 pull-up resistors to the reference power supply. The power consumption of each multiplexer or analog switch is as follows: Figure 1 The traditional BMS temperature acquisition circuit shown is reduced by 7 / 8, and the power consumption of n-way temperature switches is only n / 8 of the original, which effectively reduces the standby power consumption of the battery pack and the stability performance of the reference voltage, and greatly increases the PCB utilization rate.
[0065] Moreover, since the n NTC temperature sensors share a resistor to pull up RA to the reference voltage, the voltage error caused by the independent pull-up resistor RA of each NTC sensor is effectively reduced, and the acquisition accuracy is effectively improved.
[0066] In addition, the AFE acquisition chip module 400 is directly connected to the battery module 100, which has a certain amount of standby power consumption. Long-term standby will inevitably accelerate the over-discharge of the battery module 100. The reference voltage of the NTC temperature sensor is taken from the battery pack, and reasonable power consumption management greatly reduces the discharge current of the battery.
[0067] Embodiment 2
[0068] In some optional embodiments, the present application also provides a battery pack, comprising the BMS temperature acquisition circuit as described above.
[0069] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the structure and implementation principle of the battery pack described above can refer to the corresponding structure and implementation principle in the aforementioned embodiment 1, and will not be repeated here.
[0070] The BMS temperature acquisition circuit of the present application includes a battery module 100, a temperature acquisition module 200, a control circuit module 300 and an AFE acquisition chip module 400, wherein the battery module 100 includes a plurality of battery cells connected in series, the temperature acquisition module 200 includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on the battery pole of the corresponding battery cell, the control circuit module 300 includes at least one control unit, the signal input end of the control unit is connected to the first end of N temperature sensors, wherein N is greater than or equal to 1, the signal control end of the control unit is connected to the AFE acquisition chip module 400, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module 400, the signal output end of the control unit is connected to the reference voltage end Vref through the pull-up resistor RA, and the signal output end of the control unit is also connected to the AFE acquisition chip module 400, and is used to output the acquisition information to the controller 500 through the AFE acquisition chip module 400. Through the above settings, it is only necessary to set a pull-up resistor RA at the signal output end of the control unit, while the temperature sensor does not need to set a pull-up resistor RA, which effectively reduces the number of resistors and greatly increases the PCB utilization rate. At the same time, since N temperature sensors share one pull-up resistor RA, power consumption is reduced, the voltage error of each temperature sensor is reduced, and the acquisition accuracy is improved.
[0071] The above are only preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the present invention.
Claims
1. A BMS temperature acquisition circuit, characterized in that: Including battery module, temperature acquisition module, control circuit module and AFE acquisition chip module; The battery module includes a plurality of battery cells connected in series; The temperature acquisition module includes a plurality of temperature acquisition units corresponding to the plurality of battery cells one by one, and the temperature acquisition unit includes a temperature sensor, and the temperature sensor is arranged on a battery pole of the corresponding battery cell; The control circuit module includes at least one control unit, and a signal input terminal of the control unit is connected to N temperature sensors, wherein N is greater than or equal to 1; The signal control end of the control unit is connected to the AFE acquisition chip module, and is used to receive the acquisition information of the temperature sensor forwarded by the AFE acquisition chip module; The signal output end of the control unit is connected to the reference voltage end through a pull-up resistor, and the signal output end of the control unit is also connected to the AFE acquisition chip module, so as to output the acquisition information to the controller through the AFE acquisition chip module.
2. The BMS temperature acquisition circuit according to claim 1, characterized in that: Both ends of the temperature sensor are connected to the corresponding control unit through any one of a wiring harness, a PCB and an FPC.
3. The BMS temperature acquisition circuit according to claim 1, characterized in that: The temperature sensor is fixed near a pole of the battery cell or a position where heat is generated.
4. The BMS temperature acquisition circuit according to any one of claims 1 to 3, characterized in that: The temperature sensor is NTC.
5. The BMS temperature acquisition circuit according to claim 4, characterized in that: The temperature sensor is connected in parallel with the first capacitor.
6. The BMS temperature acquisition circuit according to claim 1, characterized in that: The signal output end of the control unit is connected to one end of a first resistor, the other end of the first resistor is connected to the AFE acquisition chip module, the other end of the first resistor is also grounded through a second capacitor, and the first resistor and the second capacitor form a low-pass filter circuit.
7. The BMS temperature acquisition circuit according to claim 1, characterized in that: The reference voltage terminal is connected to the reference voltage of the AFE acquisition chip module or to an external reference voltage.
8. The BMS temperature acquisition circuit according to claim 1, characterized in that: The control unit includes any one of a multiplexer or a multi-way analog switch.
9. The BMS temperature acquisition circuit according to claim 1, characterized in that: The AFE acquisition chip module is connected to the controller via ISOSPI or a daisy chain.
10. A battery pack, characterized in that: The method comprises the BMS temperature acquisition circuit as claimed in any one of claims 1 to 9.