CN220363249U - Battery control unit, battery management system BMS and car - Google Patents

Abstract

The application discloses battery control unit, battery management system BMS and car. The battery control unit comprises a high-voltage acquisition module and a temperature acquisition module, the battery control unit is respectively connected with the high-voltage acquisition module and the temperature acquisition module and is used for acquiring voltage information and temperature information for the BMS, and when the battery control unit acquires voltage for the BMS, the high-voltage acquisition module at least comprises an isolation chip and an isolation capacitor is arranged between a high-voltage ground and a low-voltage ground of the isolation chip; when the battery control unit collects temperature for the BMS, the temperature collection module is electrically connected with a thermistor in the temperature collection module through an FPC soft flat cable, wherein an anti-interference material is further arranged on the FPC soft flat cable. The technical scheme in this application has improved the anti-interference performance of BMS when gathering voltage and temperature, has guaranteed information acquisition's accuracy, provides the guarantee for the security of vehicle.

Description

Battery control unit, battery management system BMS and car

Technical Field

The application relates to the technical field of new energy automobiles, in particular to a battery control unit, a battery management system BMS and an automobile.

Background

Along with the progress of technology, the energy of the automobile is more and more diversified, and a Battery Management System (BMS) of the new energy automobile is used as a tie between a battery and a power system and is used for supplying power to the power system, and is also used for preventing the battery from being overcharged and overdischarged, prolonging the service life of the battery, monitoring the state of the battery and the like.

The battery management system is a set of control system for protecting the use safety of the power battery, monitors the use state of the battery, relieves the inconsistency of the battery pack, and provides guarantee for the use safety of the new energy vehicle. The collection function of the BMS is very important for vehicle safety, including high voltage collection, temperature collection, single body voltage collection, and the like. However, in the prior art, the BMS has certain interference in the process of collecting the voltage and the temperature of the battery, the collected data information has inaccurate conditions, and the driving safety can be endangered when the error is serious.

It should be noted that the statements herein merely provide background information related to the present application and may not necessarily constitute prior art.

Disclosure of Invention

In view of the above, the present application proposes a battery control unit, a battery management system BMS, and an automobile that overcome or at least partially solve the above problems.

The embodiment of the application adopts the following technical scheme:

in a first aspect, an embodiment of the present application provides a battery control unit, which is applied to a BMS, where the battery control unit includes a high voltage acquisition module and a temperature acquisition module, where the battery control unit is connected to the high voltage acquisition module and the temperature acquisition module respectively, and is configured to acquire voltage information and temperature information for the BMS, and when the battery control unit acquires voltage for the BMS, the high voltage acquisition module includes at least an isolation chip, and an isolation capacitor is set between a high voltage ground and a low voltage ground of the isolation chip; when the battery control unit collects temperature for the BMS, the temperature collection module is electrically connected with a thermistor in the temperature collection module through an FPC soft flat cable, wherein an anti-interference material is further arranged on the FPC soft flat cable.

Preferably, the isolation capacitor comprises a plurality of isolation capacitors, and the plurality of isolation capacitors are connected in series and used for providing a drainage path for interference current.

Preferably, the anti-interference material comprises a copper sheet, and a layer of copper sheet is arranged on a temperature acquisition line in the FPC flexible flat cable to wrap the temperature acquisition line.

Preferably, a layer of copper sheet is added to a second layer of the temperature acquisition line in the FPC flexible flat cable, and the temperature acquisition line is wrapped.

Preferably, the thermistor comprises an NTC thermistor, and the high-voltage acquisition module is electrically connected with the NTC thermistor through a temperature acquisition line in the FPC flexible flat cable and is used for acquiring temperature information of the battery pack.

Preferably, the temperature acquisition module further comprises an FPC plug-in component, and the FPC plug-in component enables the FPC flexible flat cable to be connected in a plug-in mode.

In a second aspect, embodiments of the present application also provide a battery management system BMS including the battery control unit according to any of the first aspects.

In a third aspect, embodiments of the present application also provide an automobile including the battery management system BMS according to the second aspect.

The above-mentioned at least one technical scheme that this application embodiment adopted can reach following beneficial effect:

the technical scheme of this application is through carrying out the anti-interference transformation to high voltage acquisition module and temperature acquisition module on the BMS for at the design earlier stage, guarantee BMS's interference immunity ability, thereby guaranteed information acquisition's accuracy, avoided later stage to appear because of structure and overall arrangement locking for the condition that can't modify, practiced thrift the cost, improved vehicle security.

The foregoing description of the embodiments of the present application is merely an overview of the embodiments of the present application, and may be implemented according to the content of the specification in order to make the technical means of the present application more clearly understood, and in order to make the above and other objects, features and advantages of the present application more readily apparent, the following detailed description of the present application will be given.

Drawings

Various other advantages and benefits will become apparent to those of ordinary skill in the art upon reading the following detailed description of the preferred embodiments. The drawings are only for purposes of illustrating the preferred embodiments and are not to be construed as limiting the application. Also, like reference numerals are used to designate like parts throughout the figures. In the drawings:

fig. 1 is a schematic structural diagram of a battery control unit according to an embodiment of the present application;

FIG. 2 is a schematic diagram of voltage acquisition in an embodiment of the present application;

FIG. 3 is a schematic diagram of temperature acquisition in an embodiment of the present application;

fig. 4 is a schematic diagram of BCU connection in an embodiment of the present application;

FIG. 5 is a schematic diagram of current disturbance in an embodiment of the present application;

FIG. 6 is a schematic diagram of voltage acquisition optimization in an embodiment of the present application;

fig. 7 is a schematic diagram of temperature acquisition optimization in an embodiment of the present application.

Detailed Description

For the purposes, technical solutions and advantages of the present application, the technical solutions of the present application will be clearly and completely described below with reference to specific embodiments of the present application and corresponding drawings. It will be apparent that the described embodiments are only some, but not all, of the embodiments of the present application. All other embodiments, which can be made by one of ordinary skill in the art without undue burden from the present disclosure, are within the scope of the present disclosure.

The technical terms referred to in this application are as follows:

BMS, (Battery Management System) battery management system;

BCU, (Battery Control Unit) battery control unit;

a MCU, (Microcontroller Unit) micro control unit;

negative temperature coefficient of NTC (Negative Temperature Coefficient)

HPC, (Horizontal Coupling Plane) horizontal coupling plate;

HBM, (Human-Body Model) Human discharge mode.

The conception of the application lies in, to current high pressure acquisition module and temperature acquisition module at voltage and temperature acquisition's in-process, can't provide comparatively stable and accurate collection information problem, has proposed a modified high pressure acquisition module and temperature acquisition module for battery control unit is not influenced by static and electromagnetic interference in the in-process of carrying out voltage and temperature acquisition, and information acquisition's stability and accuracy have obtained the assurance, have extensive application prospect.

The following describes in detail the technical solutions provided by the embodiments of the present application with reference to the accompanying drawings.

As shown in fig. 1, the battery management system BMS100 is a set of control system for protecting the use safety of the power battery, monitors the use state of the battery, relieves the inconsistency of the battery pack, and provides a guarantee for the use safety of the new energy vehicle. The collection function of the BMS is very important for vehicle safety, including high voltage collection, temperature collection, single body voltage collection, and the like. The voltage acquisition of the application is high voltage acquisition. The acquisition and control function of the BMS needs a controller, namely a battery control unit BCU (Battery Control Unit), wherein the bcu comprises a high-voltage acquisition module 1101 and a temperature acquisition module 1102, as shown in fig. 2, the high-voltage acquisition module 1101 performs high-voltage and low-voltage isolation for the high-voltage acquisition requirement, and isolation is usually realized by using an isolation chip; the isolation chip is used for performing isolation conversion on the high-voltage signals acquired by the high-voltage acquisition chip into low-voltage signals and transmitting the low-voltage signals to the MCU, the MCU is a 1.8V or 3.3V low-voltage operation system, and the power supply source of the MCU is converted through the storage battery.

As shown in fig. 3, the temperature acquisition module in the BCU is implemented by using a thermistor to acquire temperature, usually a negative temperature coefficient NTC, and is connected by adopting an FPC flexible flat cable mode, wherein one end of the FPC flexible flat cable is connected with the NTC, and the other end of the FPC flexible flat cable is connected with the BCU, so as to implement temperature acquisition.

As shown in fig. 4 and 5, when the high voltage acquisition module is subjected to the ESD test, the parts that can be touched by the human body need to be subjected to the ESD test. On the one hand, when the ESD test standard requires that the ESD test is not performed, the tested product, namely the low-voltage ground wire of the controller, needs to be connected with the horizontal coupling plate HCP, so as to better reflect the situation encountered in the actual scene: the controller low-voltage ground wire can be connected with the ground of a real vehicle in the process of carrying, maintaining and installing, and a human hand can touch a PIN (personal identification number) PIN of the controller. On the other hand, in the situation that the high-voltage ground PIN of the controller is not in an electric field scene of ESD, the voltage withstand test is equivalent to that of the isolation chip, however, the ESD of the chip can only meet the standard that the non-power-on mode HBM meets 4KV (even 2 KV), the ESD test standard needs to reach 8KV, and obviously, the chip is damaged certainly after the ESD test, so that the high-voltage acquisition is abnormal, and the high-voltage ground PIN is safe and important for vehicles. The isolation chip is damaged to cause abnormal high-voltage acquisition function, and the safety of a vehicle is directly influenced.

As shown in fig. 3, when the radiation immunity test is performed on the temperature acquisition module, if the temperature acquisition deviation is serious, the safety of the vehicle can be directly affected. When a vehicle encounters a negative electromagnetic environment, the anti-interference capability and the radiation immunity of the controller need to meet certain standards. Radiation immunity typically requires 100V/m, even up to 200V/m in some cases. Because thermistor NTC acquisition circuit connects through FPC flexible flat cable, under the radiation scene, on the line that NTC and battery control unit BCU are connected, interference current does not have good backward flow route, because the existence of gathering line impedance, can produce interference voltage (U=IR), influences the BCU and gathers, leads to the BCU to the mistake of temperature gather, runs into this problem in if the vehicle is gone, directly leads to driving safety.

Therefore, the embodiment of the application provides a battery control unit capable of solving the problems, the battery control unit comprises a high-voltage acquisition module and a temperature acquisition module, the battery control unit is respectively connected with the high-voltage acquisition module and the temperature acquisition module and is used for acquiring voltage information and temperature information for the BMS,

when the battery control unit collects voltage for the BMS, the high-voltage collection module at least comprises an isolation chip, and an isolation capacitor is arranged between high-voltage ground and low-voltage ground of the isolation chip;

when the battery control unit collects temperature for the BMS, the temperature collection module is electrically connected with a thermistor in the temperature collection module through an FPC soft flat cable, wherein an anti-interference material is further arranged on the FPC soft flat cable.

As shown in fig. 6, in the high voltage acquisition module in the battery control unit BCU, in order to solve the problem that the isolation chip may be damaged due to the ESD interference, an isolation capacitor is added between the low voltage ground and the high voltage ground of the BCU, and as a preferred scheme, two or more capacitors are connected in series, in order to meet the requirement of insulation and voltage withstanding between the high voltage and the low voltage, the voltage withstanding value of the capacitor needs to be considered when the capacitor is selected, and two capacitors of 10nf are connected in series, so that the ESD 8KV test can be met. The isolation capacitor is a Y capacitor, and the capacitance value of the Y capacitor can be selected according to actual results because the whole vehicle environment is complex and different vehicle types have possible differences, and the capacitor position is reserved on the PCB in the BCU design stage.

The technical principle that the isolation capacitor is added to solve the problem that the isolation chip is damaged is that the flowing path of interference current is changed, namely static electricity is released through the isolation capacitor, so that the isolation chip is not passed, and the purpose of protection is achieved. The scheme also has an optimization effect on radiation emission, and the technical principle is that noise on the high-voltage side of the BCU returns to low-voltage ground through the isolation capacitor and is not radiated to the outside.

As shown in fig. 7, in the temperature acquisition module in the battery control unit BCU, in order to solve the problem of inaccurate temperature information acquisition caused by electromagnetic interference, a temperature acquisition line in the FPC flexible flat cable in the temperature acquisition module is subjected to ground wrapping treatment.

As a preferable scheme, the method comprises the following specific technical scheme when carrying out packet processing:

firstly, copper sheets are added around a temperature acquisition line layer in the FPC flexible flat cable, and the acquisition line is wrapped, wherein the temperature acquisition line is preferentially selected from microstrip lines; secondly, adding a copper sheet layer on the lower layer of the temperature acquisition line in the FPC flexible flat cable; thirdly, punching a ground hole at the position close to a temperature acquisition line in the FPC flexible flat cable, and connecting the two layers of copper sheets; finally, copper sheets added in the FPC flexible flat cable are finally connected to the low-voltage ground of the BCU through a connector of the FPC. The technical scheme can solve the technical principle that the temperature acquisition of the temperature acquisition module is abnormal, namely, a reflux path is provided for the interference current, so that the interference current is ensured not to influence the actual temperature acquisition.

In some examples of the present application, the isolation capacitor includes a plurality of the isolation capacitors connected in series for providing a drain path for the disturbance current.

As shown in fig. 6, to solve the problem that the isolation chip may be damaged due to ESD, two or more capacitors are added between the low voltage ground and the high voltage ground of the BCU to better discharge static electricity. Meanwhile, in order to meet the requirement of insulation voltage withstand test between high voltage and low voltage, the voltage withstand value of the capacitor is considered when the capacitor is selected, and two 10nf series connection are preferred, so that the ESD 8KV scene can be met. The added capacitor is Y capacitor, and the capacitance value of the capacitor can be changed according to the actual result because different vehicle types can possibly have different selection values of the Y capacitor, and the capacitor position is reserved on the PCB in the BCU design stage.

In some examples of the present application, the anti-interference material includes a copper sheet, and a layer of copper sheet is disposed on a temperature acquisition line in the FPC flexible flat cable, so that the temperature acquisition line is wrapped. And a layer of copper sheet is added on a second layer of the temperature acquisition line in the FPC soft flat cable, and the temperature acquisition line is wrapped. The temperature acquisition module further comprises an FPC plug-in component, and the FPC plug-in component enables the FPC flexible flat cable to be connected in a plug-in mode.

As shown in fig. 7, the same layer of copper sheets and the lower layer of copper sheets are arranged between the temperature acquisition module of the BCU and the NTC sensor, and a plurality of ground holes are arranged between the two layers of copper sheets to connect the two layers of copper sheets, so that a reflux path can be provided for the interference current, and the influence of the interference current in the temperature acquisition process is ensured.

The present application also provides a battery management system BMS including the battery control unit as described above, and references to other parts of the BMS are made to the prior art, and are not repeated herein.

The present application also provides an automobile including a battery management system BMS having the above battery control unit, and the other parts of the automobile are referred to the prior art, and are not repeated herein.

It should be noted that in the description of the present application, the terms "first," "second," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance. Furthermore, in the description of the present application, unless otherwise indicated, the meaning of "a plurality" is two or more.

In this application, unless specifically stated and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly, and may be, for example, fixedly attached, detachably attached, or integrally formed; can be mechanically connected, electrically connected or communicable with each other; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. 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.

In this application, unless expressly stated or limited otherwise, a first feature "on" or "under" a second feature may be the first and second features in direct contact, or the first and second features in indirect contact via an intervening medium. Moreover, a first feature "above", "over" and "on" a second feature may be a first feature directly above or obliquely above the second feature, or simply indicate that the first feature is higher in level than the second feature. The first feature being "under", "under" and "beneath" the second feature may be the first feature being directly under or obliquely under the second feature, or simply indicating that the first feature is level less than the second feature.

Any process or method descriptions in flow charts or otherwise described herein may be understood as representing modules, segments, or portions of code which include one or more executable instructions for implementing specific logical functions or steps of the process, and further implementations are included within the scope of the preferred embodiment of the present application in which functions may be executed out of order from that shown or discussed, including substantially concurrently or in reverse order, depending on the functionality involved, as would be understood by those reasonably skilled in the art of the embodiments of the present application.

In the description of the present specification, reference to the terms "one embodiment," "some embodiments," "examples," "specific examples," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present application. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present application have been shown and described above, it will be understood that the above embodiments are illustrative and not to be construed as limiting the application, and that variations, modifications, alternatives, and variations may be made to the above embodiments by one of ordinary skill in the art within the scope of the application.

Claims (8)

1. The battery control unit is applied to a battery management system BMS, and is characterized by comprising a high-voltage acquisition module and a temperature acquisition module, wherein the battery control unit is respectively connected with the high-voltage acquisition module and the temperature acquisition module and is used for acquiring voltage information and temperature information for the BMS,

when the battery control unit collects voltage for the BMS, the high-voltage collection module at least comprises an isolation chip, and an isolation capacitor is arranged between high-voltage ground and low-voltage ground of the isolation chip;

when the battery control unit collects temperature for the BMS, the temperature collection module is electrically connected with a thermistor in the temperature collection module through an FPC soft flat cable, wherein an anti-interference material is further arranged on the FPC soft flat cable.

2. The battery control unit of claim 1 wherein said isolation capacitor comprises a plurality of said isolation capacitors connected in series for providing a drain path for an interfering current.

3. The battery control unit of claim 1, wherein the tamper resistant material comprises a copper sheet, and a layer of copper sheet is disposed on a temperature acquisition line in the FPC flex cable to wrap the temperature acquisition line.

4. The battery control unit of claim 3, wherein a second layer of temperature pickup wires is added to the FPC flex cable to encapsulate the temperature pickup wires.

5. The battery control unit of claim 4, wherein the thermistor comprises an NTC thermistor, and the high voltage acquisition module is electrically connected to the NTC thermistor through a temperature acquisition wire in the FPC flexible flat cable for acquiring temperature information of the battery pack.

6. The battery control unit of claim 5, wherein the temperature acquisition module further comprises an FPC plug that enables pluggable connection of the FPC flex cable.

7. A battery management system BMS, characterized by comprising the battery control unit according to any one of claims 1 to 6.

8. An automobile comprising the battery management system BMS of claim 7.