WO2020034935A1 - Battery pack monitoring device and system - Google Patents

Abstract

A battery pack monitoring device (301) and a monitoring system, the battery pack monitoring device (301) comprising a microphone module (103), a power source management system (102), and a controller (101), wherein the controller (101) sends a charge/discharge control signal to the power source management system (102); under the effect of the charge/discharge control signal, the power source management system (102) charges or discharges the battery pack (302); and during the charging/discharging process, the microphone module (103) collects a sound signal of the battery pack (302), and sends the sound signal to the controller (101) so that the controller (101) determines the magnitude of the sound signal and a preset threshold according to the received sound signal, and when the sound signal is greater than the preset threshold, it is determined that the battery pack (302) will fail. Therefore, the microphone module (103) provided on a box body (100) at which the battery pack (302) is located may be used to monitor whether the battery pack (302) fails and promptly monitor the status of the battery pack (302), so that measures are taken before the battery pack (302) fails, thereby improving driving safety.

Description

Battery pack monitoring equipment and system

This application claims priority from a Chinese patent application filed on August 16, 2018 with the Chinese Patent Office, application number 201810936033.5, and application name "A Battery Pack Monitoring Device and System", the entire contents of which are incorporated herein by reference. in.

Technical field

The invention relates to the technical field of battery pack safety monitoring, in particular to a battery pack monitoring device and system.

Background technique

With the depletion of petroleum energy and people's increasing attention to environmental pollution, electric vehicles will become the current trend.

Electric vehicles include pure electric vehicles and hybrid electric vehicles. For pure electric vehicles, power battery packs are used to provide power for vehicles, and for hybrid vehicles, oil or power battery packs are used to provide power.

Because the voltage of the power battery pack on an electric vehicle is usually several hundred volts, when the power battery pack leaks electricity, it is easy to cause personal injury to the personnel on the vehicle or the maintenance staff. Moreover, when the power battery pack leaks electricity to a certain extent, It may cause the battery to explode and damage the vehicle.

Therefore, accurate monitoring of power battery packs is required to prevent problems before they occur.

Summary of the Invention

In order to solve the above technical problems in the prior art, embodiments of the present invention provide a battery pack monitoring device and a monitoring system, which can accurately and timely monitor the status of the battery pack, and then take measures before the battery pack fails.

A first aspect of the present application provides a battery pack detection device, which includes:

Microphone module, power management system and controller;

The microphone module is arranged on the box where the battery pack is located;

The controller is configured to send a charge and discharge control signal to the power management system;

The power management system is configured to charge or discharge the battery pack when the charge and discharge control signal is received;

The controller is further configured to receive a sound signal sent by the microphone module; when it is determined that the sound signal is greater than a preset threshold, determine that the battery pack is about to fail.

Optionally, the microphone module is a microphone matrix;

The controller is further configured to obtain a position where the sound signal originates from the battery pack according to a type of the microphone matrix, and determine that a fault occurs in a battery cell at the position in the battery pack.

Optionally, before determining that the sound signal is greater than a preset threshold, the controller is further configured to:

Screening the sound signal from the sound signal between the moment when the charging current is injected by the power management system and the moment when the charging current is stopped;

The determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a first preset threshold;

or

Screening, from the sound signals, sound fragment signals between the time when the power management system controls the battery pack to be discharged and the time when discharge is stopped;

The determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a second preset threshold.

Optionally, the controller is further configured to: obtain a background sound signal outside the cabinet in advance;

The controller is further configured to subtract a background sound signal outside the cabinet from the screened sound signal before determining that the sound signal is greater than a preset threshold.

Optionally, obtaining the background sound signal outside the cabinet in advance is specifically:

Obtaining background sound signals outside the box multiple times in advance, and averaging the background sound signals obtained multiple times as the final background sound signal;

The controller subtracts the background sound signal outside the cabinet from the screened sound signal, which is specifically:

The controller subtracts the final background sound signal outside the cabinet from the screened sound signal.

Optionally, the controller sends a charge and discharge control signal to the power management system multiple times;

Each time the power management system receives the charging control signal, injects a charging current into the battery pack;

Obtaining a sound segment signal corresponding to each injection of charging current;

Obtaining an average value of the sound segment signal from the sound segment signal obtained each time, and using the average value of the sound segment signal as a final sound segment signal;

Determining that the sound segment signal is greater than a preset threshold, specifically: determining that the final sound segment signal is greater than the first preset threshold;

or

Each time the power management system receives the discharge control signal, controls the battery pack to discharge;

Obtain the sound segment signal corresponding to each discharge;

Obtaining an average value of the sound segment signal from the sound segment signal obtained each time, and using the average value of the sound segment signal as a final sound segment signal;

Determining that the sound segment signal is greater than a preset threshold, specifically: determining that the final sound segment signal is greater than the second preset threshold.

Optionally, the controller determines that the sound signal is greater than a preset threshold, specifically:

The controller performs Fourier analysis on the sound signal to obtain a digital spectrum corresponding to the sound signal. The preset threshold is an initial sound signal obtained when the factory-discharged battery pack is subjected to charge and discharge control in advance. Fourier analysis is performed on the initial sound signal to obtain a corresponding initialized digitized spectrum, and it is determined that the digitized spectrum of the sound signal is larger than the initialized digitized spectrum.

Optionally, the controller is further configured to obtain a change curve of the sound signal when determining that the sound signal is less than or equal to the preset threshold, and determine a change trend of the battery pack according to the change curve, The fault reminder period is set according to the change trend, and the fault reminder period includes: day, week, and month; different change trends correspond to different fault reminder periods.

Optionally, the controller sets a unique ID for the battery pack, and the controller sets a unique ID for the power management system;

The controller sends the charge and discharge control signal to the power management system through the ID of the power management system, and the charge and discharge control signal carries the ID of the battery pack; the power management system is configured to pass The battery pack ID charges or discharges the battery pack.

Optionally, the controller is located in a car or a remote server.

Optionally, the device further includes a remote server;

The controller is further configured to send the sound signal to the remote server;

The remote server is configured to analyze the sound signal through a neural network to obtain a change curve of the sound signal, and determine whether the battery pack is faulty according to the change curve.

The second aspect of the present application further provides a monitoring system, including the battery pack monitoring device described in the first aspect, and further including a battery pack.

Compared with the prior art, the present invention has at least the following advantages:

The battery pack monitoring device and the monitoring system provided by the present invention, wherein the battery pack monitoring device includes a microphone module, a power management system, and a controller, wherein the controller sends a charge and discharge control signal to the power management system, and plays a role in the charge and discharge control signal. Next, the power management system charges or discharges the battery pack. During the charging and discharging process, the microphone module collects the sound signal of the battery pack and sends the sound signal to the controller, so that the controller can judge the sound signal and the sound signal based on the received sound signal. The size of the preset threshold. When the sound signal is greater than the preset threshold, it is determined that the battery pack is about to fail.

It can be seen that, through the battery pack monitoring device provided by the embodiment of the present invention, a microphone module provided on the wall of the box where the battery pack is located can be used to monitor whether the battery pack is faulty, and the state of the battery pack can be accurately and timely monitored, so that the battery pack fails Take measures before to improve driving safety.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a structural diagram of a battery pack monitoring device according to an embodiment of the present invention; FIG.

2 is a structural diagram of another battery pack monitoring device according to an embodiment of the present invention;

3 is a schematic structural diagram of a battery pack according to an embodiment of the present invention;

FIG. 4 is a structural diagram of a monitoring system according to an embodiment of the present invention.

detailed description

In order to clearly explain the technical features of this solution, the present invention will be described in detail below through specific implementations and the accompanying drawings. The following disclosure provides many different embodiments or examples for implementing different structures of the invention. To simplify the disclosure of the present invention, the components and settings of specific examples are described below. In addition, the present invention may repeat reference numbers and / or letters in different examples. This repetition is for the sake of simplicity and clarity and does not in itself indicate the relationship between the various embodiments and / or settings discussed. It should be noted that the components illustrated in the drawings are not necessarily drawn to scale. The invention omits descriptions of well-known components and processing techniques and processes to avoid unnecessarily limiting the invention.

In order to facilitate understanding of the technical solution provided by the present invention, the background technology of the technical solution of the present invention is briefly described below first.

The inventor found in the research that there are currently two commonly used methods for monitoring the battery status. The first is to monitor the temperature of the battery module or the battery cell. When the temperature of the battery cell continues to rise, the battery is about to fail. However, the use of temperature monitoring cells, on the one hand, has poor timeliness; on the other hand, the battery pack may include thousands of cells, and it is obviously more expensive to set a temperature sensor for each cell, and the internal space of the battery pack limited. In addition, if only a few temperature sensors are provided, the specific location of the higher temperature battery cells cannot be located, and it is difficult to quickly and accurately find the higher temperature battery cells.

The second is to use the current injection method to judge by detecting the internal resistance of the battery pack. When the internal resistance is large, it means that no short circuit has occurred; when the internal resistance is small, it means that a short circuit has occurred. However, this method generally performs a self-test before the electric vehicle is put on the road, and cannot be detected in real time. Therefore, the safety of the battery pack cannot be guaranteed.

The inventor's research found that the structure of the battery cell includes a positive plate, a negative plate, and a heat insulation layer. After the car leaves the factory, the environment is relatively harsh, such as vibration, dust, thermal expansion and contraction, etc. may cause uneven thickness of the thermal insulation layer. In addition, when the battery is charged and discharged, the battery will also generate heat. With the increase of time, the above problems may cause a short circuit between the positive electrode plate and the negative electrode plate of the battery cell, causing the battery cell to leak electricity.

Based on this, an embodiment of the present invention provides a battery pack monitoring device. The battery pack monitoring device includes a microphone module, a power management system, and a controller. In order to detect whether a battery pack is about to fail, it is proposed to use a battery pack generated during charging and discharging. The sound signal determines whether the battery pack is about to have problems. Specifically, the controller sends a charge and discharge control signal to the power management system. Under the role of the charge and discharge control signal, the power management system charges the battery pack or controls the battery pack to discharge. In the process, the microphone module collects the sound signal of the battery pack and sends the sound signal to the controller, so that the controller judges the size of the sound signal and a preset threshold based on the received sound signal. When the sound signal is greater than the preset threshold When the battery pack is judged to be faulty, the driver is reminded to take measures to improve driving safety before the battery pack fails.

It should be noted that the battery pack monitoring device provided in the embodiment of the present application can be applied to any field using a battery, such as an electric vehicle, an electric bicycle, a mobile phone, a storage power station, and the like. To facilitate understanding, an electric vehicle is taken as an example for description below.

Example one

The battery pack monitoring device according to an exemplary embodiment of the present invention will be described in detail below with reference to the accompanying drawings.

Refer to FIG. 1, which is a structural diagram of a battery pack monitoring device according to an embodiment of the present invention.

The battery pack monitoring device provided in this embodiment may be applied to an electric vehicle, which includes a pure electric vehicle and a hybrid vehicle.

Among them, the hybrid vehicle refers to an oil-electric hybrid vehicle, that is, a conventional internal combustion engine (diesel engine or gasoline engine) and an electric motor are used as power sources. When the electric power of the hybrid vehicle is insufficient, the engine can be used to provide a power source; when the fuel of the hybrid vehicle is insufficient, the electric motor can be used to provide power energy, and the two can complement each other to increase the vehicle's cruising range.

The battery pack monitoring device provided in this embodiment includes a controller 101, a power management system 102, and a microphone module 103.

The microphone module 103 is disposed on the box where the battery pack is located. In specific implementation, the microphone module 103 can be located on the outer wall of the box or on the inner wall of the box, so that the sound signals generated by the battery can be collected more accurately. This embodiment The mounting position of the microphone module is not limited.

The controller 101 is configured to send a charge and discharge control signal to the power management system 102.

The power management system 102 is configured to charge or discharge the battery pack when the charge and discharge control signal is received.

The battery management system (BMS, Battery Management System) is the link between the battery pack and the user. Its main function is to improve the utilization of the battery pack and prevent the battery pack from being overcharged or discharged.

The controller 101 is further configured to receive a sound signal sent by the microphone module 103; when it is determined that the sound signal is greater than a preset threshold, determine that the battery pack is about to fail.

The controller may be a complete vehicle controller of an electric vehicle, or may be a controller provided independently.

The preset threshold refers to the sound signal corresponding to the charging and discharging of the battery pack when the battery pack does not fail. The sound signal can be obtained when the battery pack is charged and discharged before the vehicle leaves the factory. At the same time, the sound signal can be stored in the controller.

It can be understood that when the battery pack is faulty, when the power management system charges and discharges the battery pack, the sound signal generated by the battery pack will be different from the corresponding sound signal when no fault occurs. Therefore, this embodiment is based on the battery pack. The sound signal generated by charging and discharging determines whether the battery pack is about to fail.

The sound signals generated by the battery pack during charging and discharging are different. Therefore, when using the sound signals to determine whether the battery pack is about to fail, it is necessary to distinguish the sound signals obtained by the microphone module. Based on this, this embodiment will target different sounds. Signal for judgment.

The controller determines the type of the sound signal before determining that the sound signal is greater than a preset threshold; if the type of the sound signal is the type of the corresponding sound signal when the battery pack is charged, the controller determines that the sound signal is greater than a first preset threshold When it is determined that the battery pack is about to fail; wherein the first preset threshold is a sound signal corresponding to the power management system when charging the battery pack when the battery pack has not failed.

If the sound signal type is the sound signal type when the battery pack is discharged, it is determined that the battery pack is about to fail when the sound signal is greater than a second preset threshold; wherein the second preset threshold is that the battery pack is not When a fault occurs, the power management system controls the corresponding sound signal when the battery pack is discharged.

Because the corresponding sound signals are different when the battery pack is charged and discharged, the first preset threshold and the second preset threshold obtained in advance are also not equal.

It should be noted that since the battery pack needs to be charged by an external power source, when the battery pack state is detected by using a corresponding sound signal during charging, the vehicle can be detected only when it is stopped. The battery pack discharge process can be performed anytime, anywhere. Therefore, when detecting the battery pack state by using the corresponding sound signal during discharge, the movement state of the vehicle is not limited, and it can be a stopped state or a running state.

Because the battery pack has a service life, there is no need to monitor it in real time, and the battery pack can be monitored periodically. In order to reduce the monitoring frequency of the controller, a monitoring period T can be preset, and the controller periodically sends a charge and discharge signal to the power management system according to T, so that when the power management system receives the charge and discharge signal sent by the controller, The battery is charged and discharged.

With the battery pack monitoring device provided by the embodiment of the present invention, the controller sends a charge and discharge control signal to the power management system, so that the power management system charges and discharges the battery pack under the control signal, so that the microphone module is in the battery pack. During charging and discharging, the sound signal generated by the battery pack is collected and sent to the controller. The controller judges the size of the sound signal and a preset threshold based on the received sound signal. When the sound signal is greater than the preset threshold, Then it is judged that the battery pack is about to fail, thereby realizing timely and accurate monitoring of the state of the battery pack, and before the battery pack fails, the driver can be reminded to take measures to improve driving safety.

Example two

The above embodiment describes the composition and function implementation of the battery pack monitoring device. The specific function implementation of the battery pack monitoring device will be described in detail below with reference to the drawings.

Refer to FIG. 2, which is a structural diagram of another battery pack monitoring device according to an embodiment of the present invention.

The battery pack monitoring device provided in this embodiment includes a controller 101, a power management system 102, and a microphone matrix 203.

The controller 101 is further configured to obtain a position where the sound signal originates from the battery pack according to the type of the microphone matrix 203, and determine that a battery cell at the position in the battery pack is faulty.

The microphone matrix is a directional array, and the directivity of the directional array can be easily realized by a time domain algorithm. By controlling different delays, the directional array can be realized in different directions. The microphone matrix can be set on the inner wall of the box where the battery pack is located. When the battery pack is charged and discharged, the sound signal generated by the battery pack is collected and sent to the controller, and the controller locates the sound source of the microphone matrix Algorithm to locate the cell location in the battery pack that is about to fail.

Different types of microphone matrices correspond to different sound source localization algorithms. When the type is divided according to the size of the microphone matrix, for large microphone matrices, a method based on beamforming can be used for positioning; for small microphone matrices, a high-resolution spectrum can be used. Method of positioning. Of course, the types can also be divided according to the spatial geometric position arrangement of the microphone matrix in the microphone matrix, and different positioning algorithms corresponding to different spatial geometric position arrangements ensure accurate positioning.

It can be understood that the sound source localization algorithm of the corresponding microphone matrix can be stored in the controller according to the type of the microphone matrix used. When the battery pack is charged or discharged, the microphone matrix collects the corresponding sound signal, and The sound signal is sent to the controller, and the controller performs positioning according to a pre-stored sound source localization algorithm, so as to determine that the battery cell at a specific position in the battery pack is about to fail.

In order to facilitate understanding, refer to FIG. 3, which is a schematic structural diagram of a battery pack according to an embodiment of the present invention. The battery pack is composed of at least two battery modules 300 and is disposed in the case 100. The battery module 300 A plurality of battery cores are formed in a series-parallel manner. The microphone matrix 200 is disposed in the box 100 to collect sound signals corresponding to the charging and discharging of the battery pack. The box 100 can be installed on each electric device.

Because there are many parts loaded on the vehicle, the controller needs to control many parts. In order to ensure that the charging signal sent by the controller can be accurately received by the power management system and charge and discharge the battery pack, this embodiment is a battery pack and a power supply. The management system sets IDs separately, so that the controller uses the ID to control the power management system to charge and discharge the battery pack.

In some embodiments, the controller sets a unique ID for the battery pack, the controller sets a unique ID for the power management system, and the controller gives the power management through the ID of the power management system The system sends the charge and discharge control signal, and the charge and discharge control signal carries the ID of the battery pack; the power management system is configured to charge or discharge the battery pack through the ID of the battery pack.

In this embodiment, the ID of the battery pack and the ID of the power management system may be stored in the controller in advance. When the controller needs to send a charge and discharge signal to the power management system, the ID of the battery pack is obtained and carried in the charge and discharge signal. With the ID of the battery pack, the controller sends a charge and discharge signal to the power management system through the ID of the power management system, so that the power management system can know that the battery pack needs to be charged and discharged according to the received charge and discharge signal, improving work efficiency and avoiding power Management system misoperation.

It can be known from the foregoing embodiments that the sound signals sent by the microphone matrix may be corresponding sound signals when the battery pack is charged, or may be corresponding sound signals when the battery pack is discharged. In specific implementation, it is necessary to determine different sound signals.

In some implementations, before determining that the sound signal is greater than a preset threshold, the controller is further configured to select, from the sound signal, a time between the moment when the charging current is injected by the power management system and the moment when the charging current is stopped. A sound segment signal; determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a first preset threshold.

The power management system generally injects the charging current into the battery pack immediately after receiving the charging start signal from the controller. Therefore, the moment when the charging current is injected by the power management system can be regarded as the moment when the controller sends the charging start signal. Send by the controller, the controller can record the moment when it sends the charging start signal. Similarly, the power management system immediately stops injecting current into the battery pack when it receives the charging stop signal from the controller. Therefore, the moment when the power management system stops injecting the charging current can be regarded as the moment when the controller sends the charging stop signal. The stop signal is sent by the controller, and the controller can record the moment when it sends the charging stop signal.

Therefore, before the controller determines that the sound signal is greater than a preset threshold, it can filter out the sound segment signals between the two moments from the received sound signals based on the two moments recorded by itself, so that the controller determines the sound segment Whether the signal is greater than the first preset threshold; if it is, it indicates that the battery pack is about to fail; if not, it indicates that the battery pack is working normally.

In order to ensure the accuracy of the judgment, the sound fragment signals corresponding to the battery pack charging can be obtained multiple times, and the average value of the multiple sound fragment signals is used as the sound fragment signal used by the controller to improve the accuracy of monitoring.

In some embodiments, the controller sends a charge and discharge control signal to the power management system multiple times; each time the power management system receives the charge and discharge control signal, it injects a charge into the battery pack Current; obtain a sound fragment signal corresponding to each injection of charging current; obtain an average value of the sound fragment signal from the sound fragment signal obtained each time, and use the average value of the sound fragment signal as the final sound fragment signal; determine the sound fragment The signal is greater than a preset threshold, specifically: determining that the final sound segment signal is greater than a preset threshold.

The controller sends charging signals to the power management system multiple times so that the power management system injects charging current into the battery pack multiple times. At the same time, the controller takes the average of the multiple sound clip signals and uses the averaged sound clip signals as The final sound segment signal, so that the controller determines that the battery pack is about to fail when the final sound segment signal is greater than a preset threshold.

The above describes the controller to screen the corresponding sound segment signals when the battery pack is charged. The following describes the controller to screen the corresponding sound segment signals when the battery pack is discharged.

In some embodiments, before determining that the sound signal is greater than a preset threshold, the controller is further configured to select, from the sound signal, a time interval between the time when the power management system controls the battery pack to be discharged and the time when the discharge is stopped. A sound segment signal; determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a second preset threshold.

The power management system controls the battery pack to discharge immediately when it receives the discharge start signal sent by the controller. Therefore, the time when the battery pack is controlled by the power management system can be regarded as the time when the controller sends the discharge start signal. The controller can record the moment when it sends the discharge start signal. Similarly, the power management system immediately controls the battery pack to stop discharging when it receives the discharge stop signal from the controller. Therefore, the time when the power management system controls the battery pack to stop discharging can be regarded as the time when the controller sends the discharge stop signal. The stop signal is sent by the controller, and the controller can record the moment when it sends the charging stop signal.

Therefore, before determining that the sound signal is greater than a preset threshold, the controller can filter out the sound segment signals between the two times from the received sound signals according to the two moments recorded by itself, so that the controller judges the sound Whether the segment signal is greater than the second preset threshold; if it is, it indicates that the battery pack is about to fail; if not, it indicates that the battery pack is working normally.

Of course, in order to ensure the accuracy of the judgment, the sound fragment signals corresponding to the battery pack discharge can be obtained multiple times, and the average value of the multiple sound fragment signals is used as the sound fragment signal used by the controller to improve the accuracy of monitoring.

In some embodiments, the controller sends a charge and discharge control signal to the power management system multiple times; each time the power management system receives the discharge control signal, controls the battery pack to discharge; and obtains each discharge A corresponding sound fragment signal; obtaining an average value of the sound fragment signal from the sound fragment signal obtained each time, and using the average value of the sound fragment signal as the final sound fragment signal; judging that the sound fragment signal is greater than a preset threshold, specifically : Determine that the final sound segment signal is greater than the second preset threshold.

The controller sends discharge signals to the power management system multiple times so that the power management system controls the battery pack to discharge. At the same time, the controller averages the multiple sound clip signals and uses the averaged sound clip signals as the final sound clip signals. When the controller determines whether the final sound segment signal is greater than the second preset threshold, if it is, it indicates that the battery pack is about to fail; if not, it indicates that the battery pack is normal.

In this embodiment, since the sound signals corresponding to the charging and discharging of the battery pack are different, when using the sound signal to detect whether the battery pack is about to fail, two kinds of sound signals can be collected at the same time, and the battery pack is monitored using the two sound signals to ensure the battery pack. Package monitoring accuracy. Of course, this embodiment does not limit the form of the sound signals collected by the microphone matrix. Only one of the sound signals may be collected, or two sound signals may be collected at the same time. In specific applications, the sound signals may be collected according to actual requirements.

In this embodiment, the controller may be located in a car or a remote server. When the controller is located in the car, the operation of comparing the controller with the reference sound signal according to the sound signal is performed locally. When the controller is located on a remote server, the comparison operation between the sound signal and the reference sound signal is performed on the remote server. Specifically, the controller may send the received sound signal to the remote server, and the remote server may send the received sound signal to the reference sound signal. Compare and judge whether the battery pack is faulty according to the comparison result.

This embodiment may also use a neural network to determine whether the door lock is normal. Specifically, the controller is further configured to send the sound signal to the remote server; the remote server is configured to perform a neural network The sound signal is analyzed to obtain a change curve of the sound signal, and it is determined whether the battery pack is faulty according to the change curve.

In practical applications, the sound signals generated during the operation of the battery pack can be obtained multiple times. The neural network is trained using multiple sound signals to obtain the trained neural network. Since the trained neural network has obtained the sound generated during the normal operation of the battery pack The characteristics of the change curve of the signal. Therefore, the trained neural network can determine whether the battery pack is normal according to the characteristics of the change curve of the input sound signal.

It can be understood that when using the microphone matrix to collect sound signals, it is inevitable to collect background sound signals outside the box where the battery pack is located. In order to ensure that the controller judges the sound signal, the sound signal determined is that the battery pack is being charged and discharged. The sound signal corresponding to the time improves the accuracy of subsequent judgment. In this embodiment, before the controller judges the sound signal, the sound signal can be denoised to remove the background sound signal outside the cabinet.

In some embodiments, a background sound signal outside the cabinet is obtained in advance; the controller is further configured to subtract the sound signal of the cabinet from the screened sound signal before determining that the sound signal is greater than a preset threshold. Outside background sound signal.

The background sound signal may be a sound signal generated by other parts of the vehicle, or of course, a sound signal generated by an object other than the vehicle.

In this embodiment, the background sound signal can be obtained in advance and stored in the controller. Before the controller determines that the sound signal is greater than a preset threshold, the sound signal sent by the microphone matrix is subtracted from the pre-stored background sound signal to ensure that the controller determines The sound signal is the sound signal generated when the battery pack is charged and discharged, which avoids the influence of the background sound signal on the judgment result, thereby improving the accuracy of the battery pack condition monitoring.

The method of specifically removing the background sound signal can be eliminated by using different filtering methods according to the characteristics of the background sound signal. For example, the background sound signal appears as a high-frequency feature, and a low-pass filtering method can be used to filter the background sound signal; the background sound signal shows a low-frequency feature, and a high-pass filtering method can be used to filter the background sound signal. Of course, it can also be removed according to other attributes of the background sound signal, which is not limited in this embodiment.

In order to ensure that the background sound signal in the sound signal can be removed as much as possible, in some embodiments, obtaining the background sound signal outside the box in advance is specifically: obtaining the background outside the box multiple times in advance. The sound signal is an average value of the background sound signals obtained multiple times as the final background sound signal; the controller subtracts the background sound signals outside the cabinet from the screened sound signals, specifically: the control The device subtracts the final background sound signal outside the cabinet from the screened sound signal.

In this embodiment, background sound signals are collected multiple times, and the background signals collected multiple times are averaged, and the averaged background sound signal is used as the final background sound signal to avoid errors in the background sound signals collected at one time.

At the same time, the final background sound signal can be stored in the controller. Before the controller judges the sound signal, the final background sound signal is subtracted from the screened sound signal to obtain the final sound fragment signal, so that the controller can determine the final sound fragment signal. Whether it is greater than a preset threshold, and then determining whether the battery pack is about to fail.

In some embodiments, the controller determines that the sound signal is greater than a preset threshold, specifically: the controller performs Fourier analysis on the sound signal to obtain a digital spectrum corresponding to the sound signal, and The preset threshold is an initial sound signal obtained when the factory-manufactured battery pack is subjected to charge and discharge control in advance, and a Fourier analysis is performed on the initial sound signal to obtain a corresponding initialized digital spectrum, and it is determined that the digital spectrum of the sound signal is greater than the Initialize the digitized spectrum.

In this embodiment, the initial sound signal corresponding to the battery pack for charging and discharging can be obtained in advance before the electrical equipment is shipped, and a Fourier analysis is performed on the initial sound signal to obtain a corresponding initialized digital spectrum, which is stored in the controller. After the electric device is delivered, during the use of the electric device, when the microphone matrix sends the collected sound signal corresponding to the charging and discharging of the battery pack to the controller, the controller performs a Fourier analysis on the sound signal to obtain the sound signal. When the corresponding digitized spectrum is determined and the digitized spectrum corresponding to the sound signal is greater than the initialized digitized spectrum, it indicates that the battery pack is about to fail.

It can be understood that, because the sound signals generated when the battery pack is charged and discharged are different, the digital spectrum obtained through Fourier analysis is also different.

In practical applications, the controller can monitor the working status of the battery pack in real time, and the status change trend of the battery pack can be obtained through long-term monitoring. The controller can predict the future failure of the battery pack based on the long-term statistical change trend, and Set a fault reminder so that you can promptly remind the driver to pay attention to maintenance or replace the battery pack in advance to avoid affecting the driving experience when the battery pack fails.

In some embodiments, the controller is further configured to obtain a change curve of the sound signal when it is determined that the sound signal is less than or equal to the preset threshold, and determine a change of the battery pack according to the change curve. Trend, the fault reminder period is set according to the change trend, the fault reminder period includes: day, week and month; different change trends correspond to different fault reminder periods.

In this embodiment, the controller obtains the sound signals corresponding to the battery pack during charging and discharging in real time, and performs statistics, processing, and analysis to obtain the change curve of the sound signals, which is corresponding to the time when the battery pack is charged and discharged when the vehicle leaves the factory. The change curves are compared, and when it is judged that the corresponding sound signal change curve changes suddenly when the current battery pack is charged and discharged, the user is reminded of the fault according to the set fault reminding period.

Different change trends indicate that the battery pack will fail at different times. When the change trend is more prominent, the fault reminder period can be set to remind in units of days. For example, the fault reminder period is reminded once every two days. When the change trend is relatively gentle, the fault reminder period can be set to remind in week or month. For example, the fault reminder period is reminded once a week.

According to the battery pack monitoring device provided by the embodiment of the present invention, in order to avoid the influence of the background sound signal outside the cabinet on the judgment result, the background sound signal is obtained in advance, and the sound sent by the microphone module is transmitted before the controller determines that the sound signal is greater than a preset threshold. The background sound signal is subtracted from the signal to ensure that the sound signal judged by the controller is the corresponding sound signal when the battery pack is charged and discharged, which improves the accuracy of the judgment. In addition, the controller can also set a fault reminder period based on the long-term monitoring trend of the battery pack, so that the driver can be promptly reminded to overhaul or replace the battery pack to improve the driving experience.

Example three

This embodiment also provides a monitoring system. The system provided by this embodiment will be described below with reference to the drawings.

Referring to FIG. 4, a diagram of a system structure according to an embodiment of the present invention is shown.

The monitoring system of this embodiment includes the battery pack monitoring device 301 of the first and second embodiments, and further includes a battery pack 302.

The battery pack monitoring device 301 is configured to monitor a fault state of the battery pack.

Among them, the battery pack 302 is used to provide power for the electric equipment.

It should be noted that the specific function implementation of the battery pack monitoring device in this embodiment may participate in the functions described in Embodiment 1 or Embodiment 2, and details are not described herein again.

Through the monitoring system provided by this embodiment, the working status of the battery pack can be monitored in real time by using the battery pack monitoring device, so that the state of the battery pack can be accurately monitored in time, and then measures can be taken before the battery pack fails.

Although the specific embodiments of the present invention are described above with reference to the accompanying drawings, they are not a limitation on the protection scope of the present invention. Those skilled in the art should understand that based on the technical solution of the present invention, those skilled in the art do not need to make creative work. Various modifications or variations that can be made are still within the protection scope of the present invention.

Claims (12)

1. A battery pack monitoring device, characterized in that the device includes:

   Microphone module, power management system and controller;

   The microphone module is arranged on the box where the battery pack is located;

   The controller is configured to send a charge and discharge control signal to the power management system;

   The power management system is configured to charge or discharge the battery pack when the charge and discharge control signal is received;

   The controller is further configured to receive a sound signal sent by the microphone module; when it is determined that the sound signal is greater than a preset threshold, determine that the battery pack is about to fail.
2. The battery pack monitoring device according to claim 1, wherein the microphone module is a microphone matrix;

   The controller is further configured to obtain a position where the sound signal originates from the battery pack according to a type of the microphone matrix, and determine that a fault occurs in a battery cell at the position in the battery pack.
3. The battery pack monitoring device according to claim 1, wherein before the controller determines that the sound signal is greater than a preset threshold, the controller is further configured to:

   Screening the sound signal from the sound signal between the moment when the charging current is injected by the power management system and the moment when the charging current is stopped;

   The determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a first preset threshold;

   or

   Screening, from the sound signals, sound fragment signals between the time when the power management system controls the battery pack to be discharged and the time when discharge is stopped;

   The determining that the sound signal is greater than a preset threshold is specifically: determining that the sound segment signal is greater than a second preset threshold.
4. The battery pack monitoring device according to claim 3, further comprising:

   Obtaining a background sound signal outside the cabinet in advance;

   The controller is further configured to subtract a background sound signal outside the cabinet from the screened sound signal before determining that the sound signal is greater than a preset threshold.
5. The battery pack monitoring device according to claim 4, wherein the obtaining the background sound signal outside the box in advance is specifically:

   Obtaining background sound signals outside the box multiple times in advance, and averaging the background sound signals obtained multiple times as the final background sound signal;

   The controller subtracts the background sound signal outside the cabinet from the screened sound signal, which is specifically:

   The controller subtracts the final background sound signal outside the cabinet from the screened sound signal.
6. The battery pack monitoring device according to claim 3, wherein the controller sends a charge and discharge control signal to the power management system multiple times;

   Each time the power management system receives the charging control signal, injects a charging current into the battery pack;

   Obtaining a sound segment signal corresponding to each injection of charging current;

   Obtaining an average value of the sound segment signal from the sound segment signal obtained each time, and using the average value of the sound segment signal as a final sound segment signal;

   Determining that the sound segment signal is greater than a preset threshold, specifically: determining that the final sound segment signal is greater than the first preset threshold;

   or

   Each time the power management system receives the discharge control signal, controls the battery pack to discharge;

   Obtain the sound segment signal corresponding to each discharge;

   Obtaining an average value of the sound segment signal from the sound segment signal obtained each time, and using the average value of the sound segment signal as a final sound segment signal;

   Determining that the sound segment signal is greater than a preset threshold, specifically: determining that the final sound segment signal is greater than the second preset threshold.
7. The battery pack monitoring device according to claim 1, wherein the controller determines that the sound signal is greater than a preset threshold, specifically:

   The controller performs Fourier analysis on the sound signal to obtain a digital spectrum corresponding to the sound signal. The preset threshold is an initial sound signal obtained when the factory-discharged battery pack is subjected to charge and discharge control in advance. Fourier analysis is performed on the initial sound signal to obtain a corresponding initialized digitized spectrum, and it is determined that the digitized spectrum of the sound signal is larger than the initialized digitized spectrum.
8. The battery pack monitoring device according to claim 1, wherein the controller is further configured to obtain a change curve of the sound signal when it is determined that the sound signal is less than or equal to the preset threshold, and according to the The change curve determines a change trend of the battery pack, and sets a fault reminder period according to the change trend. The fault reminder period includes: day, week, and month; different change trends correspond to different fault reminder periods.
9. The battery pack monitoring device according to claim 1, wherein the controller sets a unique ID for the battery pack, and the controller sets a unique ID for the power management system;

   The controller sends the charge and discharge control signal to the power management system through the ID of the power management system, and the charge and discharge control signal carries the ID of the battery pack; the power management system is configured to pass The battery pack ID charges or discharges the battery pack.
10. The battery pack monitoring device according to claim 1, wherein the controller is located in a car or a remote server.
11. The battery pack monitoring device according to claim 10, wherein the device further comprises a remote server;

    The controller is further configured to send the sound signal to the remote server;

    The remote server is configured to analyze the sound signal through a neural network to obtain a change curve of the sound signal, and determine whether the battery pack is faulty according to the change curve.
12. A monitoring system, comprising the battery pack monitoring device according to any one of claims 1-11, and further comprising: a battery pack.

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