State monitoring method for mechanical damage problem of automobile battery pack

Abstract

The invention discloses a state monitoring method for a mechanical damage problem of an automobile battery pack in the technical field of new energy automobiles. The state monitoring method comprises the following steps: taking vibration data measured at a preset position; processing according to the vibration data to obtain corresponding acceleration response data; calculating the acceleration response data through a preset algorithm, and comparing a calculation result with the initial modal frequency to judge a damage condition; alarm prompting is carried out according to the damage condition; according to the invention, by acquiring the vibration data of the preset position, processing and comparing the data, and comparing the data with the initial modal frequency, the abnormity of the battery pack can be accurately identified, and the detection precision of mechanical damage is significantly improved; meanwhile, when abnormity is detected, alarm prompt can be triggered in real time, potential faults of the battery pack are effectively warned, and the safety and reliability of the new energy automobile are improved.

Description

Technical Field

[0001] The invention relates to a state monitoring method for mechanical damage of an automobile battery pack, belonging to the technical field of new energy automobiles. Background Art

[0002] With the vigorous development of the new energy vehicle industry, the safety and reliability of battery packs, as the core components of new energy vehicles, have received increasing attention. Although the battery management system (BMS) technology is becoming increasingly mature, battery packs still face many challenges in actual use, especially the problem of battery damage caused by external factors such as mechanical impact and collision, which has become an important issue that needs to be solved urgently.

[0003] New energy vehicles may encounter various unforeseen mechanical impacts or collision accidents during driving. Due to external factors such as traffic accidents, uneven roads, and human errors, the vehicle may come into physical contact with obstacles, which in turn may impact or squeeze the battery pack. This external impact may directly act on the battery pack's shell, module or battery cell, causing a series of safety issues. When the battery pack is hit, its shell and internal structure may be damaged to varying degrees. The rupture of the shell will cause the seal of the battery pack to fail, exposing the internal battery cell to the external environment, increasing the risk of short circuit and leakage. At the same time, the deformation or fracture of the internal structure may affect the fixation and support of the battery pack, further aggravating the degree of damage to the battery cell. Serious consequences of battery cell damage The battery cell is the core component of the battery pack, which contains flammable and explosive electrolytes and active substances. During the external mechanical impact and collision, the battery monomer is damaged, which in turn causes safety hazards such as short circuit, leakage, combustion or explosion. With the popularization of electric vehicles, such accidents occur frequently and are difficult to avoid completely.

[0004] Mechanical impact and collision accidents are often sudden and unpredictable. Although new energy vehicle manufacturers have taken a series of measures to improve the impact resistance of battery packs during vehicle design and production, it is still difficult to completely avoid mechanical impact and collision accidents in the face of complex and changing road environments and human factors. Therefore, the safety issues of new energy vehicle battery packs need to be continuously paid attention to and studied in depth to continuously improve their safety and reliability. Summary of the invention

[0005] The purpose of the present invention is to overcome the deficiencies in the prior art. Existing automobile battery packs are at risk of being damaged to varying degrees during driving. There is currently a lack of a stable and reliable detection method for such damage, thereby avoiding hidden dangers.

[0006] In order to solve the above technical problems, the present invention is implemented by adopting the following technical solutions:

[0007] In a first aspect, a state monitoring method for mechanical damage of an automobile battery pack is provided, comprising:

[0008] Obtain vibration data measured at a preset position;

[0009] Obtaining corresponding acceleration response data according to vibration data processing;

[0010] The acceleration response data is calculated using a preset algorithm and the calculation results are compared with the initial modal frequency to determine the damage condition;

[0011] An alarm is issued according to the damage situation.

[0012] Further, the obtaining of vibration data measured at a preset position includes: obtaining vibration data of the battery pack through an acceleration sensor;

[0013] The acceleration sensor is arranged on the bottom plate of the battery pack according to a preset rule, and the preset rule is determined by the structural characteristics and force of the battery pack itself.

[0014] Furthermore, the number of the acceleration sensor is at least one.

[0015] Furthermore, the preset algorithm includes: an impact signal modal frequency analysis algorithm, which calculates frequency data and amplitude data corresponding to each acceleration response data through the impact signal modal frequency analysis algorithm.

[0016] Furthermore, the preset algorithm also includes: performing gradient operation on the frequency data and the amplitude data, extracting the local maximum value of the amplitude in the frequency domain space formed by the frequency data, and defining the frequency corresponding to the local maximum value as the extreme value frequency;

[0017] Among them, they are arranged in ascending order according to the magnitude of the extreme value frequencies to form an extreme value frequency array and an amplitude array.

[0018] Further, the comparison with the initial modal frequency includes: comparison of the extreme frequency array with the initial modal frequency;

[0019] Wherein, the initial modal frequency includes overall modal data and local modal data;

[0020] When the ratio of the extreme frequency to the initial value of the overall mode is less than 85%, the overall mode is judged to be abnormal;

[0021] When the ratio of the extreme frequency to the local mode initial value is less than 90%, it is determined that the local mode is abnormal.

[0022] Furthermore, the extreme frequency corresponding to the value with the largest amplitude in the amplitude array is the main modal frequency;

[0023] When the frequency domain amplitude of the main modal frequency is greater than 200% of the frequency domain amplitude of the initial modal frequency, it is judged as a main modal abnormality.

[0024] In a second aspect, a state monitoring device for mechanical damage of an automobile battery pack is provided, comprising:

[0025] A data acquisition module, used to obtain vibration response data at different positions of the battery pack bottom plate, and process the vibration response data to form acceleration response data;

[0026] The modal analysis module is used to perform frequency domain analysis on the acceleration response data, extract the extreme frequency and amplitude, and generate the extreme frequency array and extreme amplitude array;

[0027] A processing module is used to classify and compare extreme frequency and amplitude;

[0028] The detection result determination module is used to determine the fault detection result and output a signal.

[0029] In a third aspect, a state monitoring system for mechanical damage problems of an automobile battery pack is provided, comprising a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of any one of the above methods are performed.

[0030] In a fourth aspect, a computer-readable storage medium stores a computer program, which implements the steps of any of the above methods when executed by a processor.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1. The present invention can accurately identify abnormalities in the battery pack by acquiring vibration data at a preset position, processing and comparing the data, and comparing the data with the initial modal frequency, thereby significantly improving the detection accuracy of mechanical damage; at the same time, when an abnormality is detected, an alarm prompt can be triggered in real time, effectively warning of potential battery pack failures and improving the safety and reliability of new energy vehicles. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figure 1 It is a module diagram of a state monitoring device for mechanical damage of an automobile battery pack according to an embodiment of the present invention;

[0034] Figure 2 Shown is a flow chart of a method for monitoring the state of mechanical damage to a vehicle battery pack according to an embodiment of the present invention. DETAILED DESCRIPTION

[0035] The present invention will be further described below in conjunction with the accompanying drawings. The following embodiments are only used to more clearly illustrate the technical solution of the present invention, and cannot be used to limit the protection scope of the present invention.

[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" 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 or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0037] Embodiment 1:

[0038] like Figure 2 As shown, a state monitoring method for a mechanical damage problem of an automobile battery pack is provided, comprising: a state monitoring method for a mechanical damage problem of an automobile battery pack comprises: obtaining vibration data measured at a preset position; obtaining corresponding acceleration response data according to vibration data processing;

[0039] When the battery pack bottom plate is subjected to mechanical collision or impact by external objects, the sensor signal is converted by AD and amplified and filtered by the acquisition module to obtain the acceleration response data of the bottom plate {X(1) X(2)…X(j)…X(n)}, where X(j) is the acceleration response of the jth sampling point in cycle n.

[0040] The acceleration response data is calculated by a preset algorithm and the calculation result is compared with the initial modal frequency to determine the damage condition; based on the acceleration response data and the impact signal modal frequency analysis algorithm,

[0041] The specific algorithm formula is:

[0042]

[0043]

[0044] Where i is the number of acceleration sensors; and then a set of frequency arrays { } and the corresponding amplitude array { }. Further, the array { } Perform gradient calculation to obtain the extreme value of the amplitude in the frequency domain space and the corresponding frequency. The corresponding frequency here is called the extreme value frequency.

[0045] Arrange the acquired extreme frequency and the corresponding amplitude extreme value in ascending order to obtain the array { }、{ },in .

[0046] In the process of obtaining the vibration data measured at the preset position, the vibration data of the battery pack is obtained by an acceleration sensor, and i acceleration sensors are arranged on the bottom plate of the battery pack. Here, i groups of { }array, { } array; the acceleration sensors are arranged on the bottom plate of the battery pack according to a preset rule, and the preset rule is determined by the structural characteristics and force of the battery pack itself; in this embodiment, the arrangement of the acceleration sensors determines their distribution positions and quantities according to the structural characteristics and force analysis of the battery pack to ensure that they can fully cover and accurately reflect the vibration of the bottom plate. In general, the number of acceleration sensors is set to i>1; considering factors such as system cost and detection effect, i is preferably 4, 5, or 6.

[0047] The preset algorithm includes: an impact signal modal frequency analysis algorithm, which calculates frequency data and amplitude data corresponding to each acceleration response data through the impact signal modal frequency analysis algorithm.

[0048] The preset algorithm further includes: performing gradient operation on the frequency data and the amplitude data, extracting the local maximum value of the amplitude in the frequency domain space formed by the frequency data, and defining the frequency corresponding to the local maximum value as the extreme value frequency;

[0049] Among them, they are arranged in ascending order according to the magnitude of the extreme value frequencies to form an extreme value frequency array and an amplitude array.

[0050] The comparison with the initial modal frequency includes: comparing the extreme frequency array with the initial modal frequency;

[0051] Wherein, the initial modal frequency includes overall modal data and local modal data;

[0052] When the ratio of the extreme frequency to the initial value of the overall mode is less than 85%, the overall mode is judged to be abnormal;

[0053] When the ratio of the extreme frequency to the local mode initial value is less than 90%, it is determined that the local mode is abnormal.

[0054] The extreme frequency corresponding to the value with the largest amplitude in the amplitude array is the main modal frequency;

[0055] When the frequency domain amplitude of the main modal frequency is greater than 200% of the frequency domain amplitude of the initial modal frequency, it is judged as a main modal abnormality.

[0056] The processing module is preset with standard modal frequency information, which is the overall modal and local modal information of the initial state of the battery pack bottom plate, obtained through experimental testing or simulation test methods; the {} array, in ascending order, compared with the preset modal frequencies, and filled in the preset table in turn, as shown in Table 1:

[0057] Table 1 Modal frequency table

[0058] Number <![CDATA[f B1 ]]> <![CDATA[f B2 ]]> … … … … <![CDATA[f BB ]]> 1 <![CDATA[f Z11 ]]> <![CDATA[f Z12 ]]> … … … … <![CDATA[f Z1 ]]> … … … … … … … … … … … … … … … … i <![CDATA[f Zi1 ]]> <![CDATA[f Zi2 ]]> … … … … <![CDATA[f Zi ]]>

[0059] The filling rule of the above table is: fill in the table in ascending order;

[0060] 2. , where fB is the frequency information preset in the system.

[0061] Accordingly, we can get the } is not listed in Table 2 in this embodiment.

[0062] Furthermore, arithmetic operations are performed on the data in each column of Table 1. The arithmetic operations here specifically include the mean calculation, variance calculation, maximum value and minimum calculation of the data; { }、{ }、{ }、{Min( }.

[0063] Then, according to the preset overall mode and local mode grouping rules, Table 1 can be divided into overall mode blocks and local mode blocks. } is compared with each modal threshold Fi. When it is less than the modal threshold, an alarm will be issued; here the overall modal threshold is 85% of the initial value, and the local modal threshold is 90% of the initial value.

[0064] Furthermore, the maximum value operation Max(a) is performed on the data in Table 2 to obtain the main modal frequency of the base plate. The main modal frequency is the frequency component corresponding to the maximum amplitude in the frequency domain. When Max(a) is greater than the modal threshold A, an alarm will be issued; here the threshold A is set to 200%*initial value.

[0065] Embodiment 2:

[0066] like Figure 1 As shown, a state monitoring device for mechanical damage of a vehicle battery pack includes:

[0067] A data acquisition module is connected to the acceleration sensor, and is used to obtain vibration response data of different positions of the battery pack bottom plate, and process the vibration response data to form acceleration response data; wherein a plurality of acceleration sensors are provided, and are arranged on the battery pack bottom plate according to a preset rule, and are used to monitor the vibration response of the bottom plate at different positions; wherein the preset rule is arranged as described in the method of embodiment 1;

[0068] The processing module receives the data transmitted by the data acquisition module, calculates the magnitude of the modal frequency after the bottom plate is impacted or impacted multiple times through a preset algorithm, and compares the sensor test results and the algorithm calculation results with the fault threshold to determine whether the battery pack is damaged;

[0069] The modal analysis module is integrated in the processing unit and is used to calculate the modal size of the base plate based on the sensor response data, especially the modal and local modal at the impact point, and compare and analyze it with the initial modal value to further determine whether the battery pack has a fault or damage;

[0070] An alarm device, connected to the processing unit, for sounding an alarm when damage or failure of the battery pack is detected;

[0071] The detection result determination module is used to determine the fault detection result and output a signal.

[0072] Embodiment three:

[0073] This embodiment provides a state monitoring system for mechanical damage problems of automobile battery packs, including a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the method described in the above embodiment 1 are executed.

[0074] Embodiment 4:

[0075] This embodiment provides a computer-readable storage medium on which a computer program is stored. When the program is executed by a processor, the steps of the method described in the above embodiment 1 are implemented.

[0076] The above is only a preferred embodiment of the present invention. It should be pointed out that for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the technical principles of the present invention. These improvements and modifications should also be regarded as the scope of protection of the present invention.

Claims

1. A state monitoring method for mechanical damage of an automobile battery pack, characterized in that: include: Obtain vibration data measured at a preset position; Processing the vibration data to obtain acceleration response data; Calculating the acceleration response data using a preset algorithm to obtain frequency data and amplitude data corresponding to the acceleration response data; Perform gradient operations on the frequency data and the amplitude data respectively to obtain the extreme frequency, and form arrays of the extreme frequency and the amplitude data respectively; The extreme frequency is compared with the overall modal data and local modal data in the initial modal frequency, and the corresponding main modal frequency in the amplitude data is compared with the frequency domain amplitude of the initial modal frequency. The damage condition is judged based on the comparison results.

2. The state monitoring method for mechanical damage of a vehicle battery pack according to claim 1, characterized in that: The obtaining of vibration data measured at a preset position includes: obtaining vibration data of the battery pack through an acceleration sensor; The acceleration sensor is arranged on the bottom plate of the battery pack according to a preset rule, and the preset rule is determined by the structural characteristics and force of the battery pack itself.

3. The state monitoring method for mechanical damage of a vehicle battery pack according to claim 2, characterized in that: The number of the acceleration sensor is at least one.

4. The state monitoring method for mechanical damage of automobile battery pack according to claim 1, characterized in that: The preset algorithm includes: an impact signal modal frequency analysis algorithm, which calculates frequency data and amplitude data corresponding to each acceleration response data through the impact signal modal frequency analysis algorithm.

5. The state monitoring method for mechanical damage of automobile battery pack according to claim 1, characterized in that: The preset algorithm further includes: performing gradient operation on the frequency data and the amplitude data, extracting the local maximum value of the amplitude in the frequency domain space formed by the frequency data, and defining the frequency corresponding to the local maximum value as the extreme value frequency; Among them, they are arranged in ascending order according to the magnitude of the extreme value frequencies to form an extreme value frequency array and an amplitude array.

6. The state monitoring method for mechanical damage of a vehicle battery pack according to claim 5, characterized in that: The comparison with the initial modal frequency includes: comparing the extreme frequency array with the initial modal frequency; Wherein, the initial modal frequency includes overall modal data and local modal data; When the ratio of the extreme frequency to the initial value of the overall mode is less than 85%, the overall mode is judged to be abnormal; When the ratio of the extreme frequency to the local mode initial value is less than 90%, it is determined that the local mode is abnormal.

7. The state monitoring method for mechanical damage of an automobile battery pack according to claim 5, characterized in that: The extreme frequency corresponding to the value with the largest amplitude in the amplitude array is the main modal frequency; When the frequency domain amplitude of the main modal frequency is greater than 200% of the frequency domain amplitude of the initial modal frequency, it is judged as a main modal abnormality.

8. A state monitoring device for mechanical damage of an automobile battery pack, characterized in that: include: A data acquisition module, used to obtain vibration response data at different positions of the battery pack bottom plate, and process the vibration response data to form acceleration response data; The modal analysis module is used to perform frequency domain analysis on the acceleration response data, extract the extreme frequency and amplitude, and generate the extreme frequency array and extreme amplitude array; A processing module is used to classify and compare extreme frequency and amplitude; The detection result determination module is used to determine the fault detection result and output a signal.

9. A state monitoring system for mechanical damage of automobile battery packs, characterized in that: The method comprises a processor and a memory connected to the processor, wherein a computer program is stored in the memory, and when the computer program is executed by the processor, the steps of the method according to any one of claims 1 to 7 are performed.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the method described in any one of claims 1 to 7 are implemented.

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