CN115664004A

CN115664004A - Energy storage system safety monitoring method, device, equipment and storage medium

Info

Publication number: CN115664004A
Application number: CN202211273805.4A
Authority: CN
Inventors: 李运生; 陈娟
Original assignee: Sungrow Power Supply Co Ltd
Current assignee: Sungrow Power Supply Co Ltd
Priority date: 2022-10-18
Filing date: 2022-10-18
Publication date: 2023-01-31

Abstract

The invention discloses a method, a device and equipment for monitoring the safety of an energy storage system and a computer readable storage medium, wherein the method comprises the following steps: acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the running process of the energy storage system; for each to-be-monitored battery cell, dividing the to-be-monitored battery cells into the same group of battery cells according to a preset grouping rule, and comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result; and determining the safety monitoring result of the battery cell to be monitored according to the parameter comparison result obtained by comparing the battery cell to be monitored in at least one group. The invention reduces the condition of false detection when the safety monitoring is carried out on the battery cell in the energy storage system, and improves the accuracy of the safety monitoring on the energy storage system.

Description

Energy storage system safety monitoring method, device, equipment and storage medium

Technology neighborhood

The present invention relates to the field of energy storage system technologies, and in particular, to a method, an apparatus, a device, and a computer-readable storage medium for monitoring safety of an energy storage system.

Background

With the accelerated propulsion of the energy storage system, the safety problem of the energy storage system is a core head concern. In the operation process of the energy storage system, a battery cell may cause fire due to the occurrence of internal short circuit and other conditions, so that the safety state of the cell needs to be monitored in the operation process of the energy storage system, and preventive and protective measures are taken to find problems as soon as possible. Currently, the safety monitoring of the energy storage system is realized by independently sampling the temperature of each battery cell and giving an alarm when the temperature of a single battery cell is too high. The safety monitoring method does not consider the relevance among the battery cells, thereby possibly causing the problem of judgment error.

Disclosure of Invention

The invention mainly aims to provide a method, a device and equipment for monitoring the safety of an energy storage system and a computer readable storage medium, and aims to provide a safety monitoring scheme of the energy storage system, which considers the incidence relation among all battery cores of the energy storage system, and improves the accuracy of safety monitoring.

In order to achieve the above object, the present invention provides a method for monitoring safety of an energy storage system, the method comprising the following steps:

acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the running process of the energy storage system;

for each to-be-monitored battery cell, dividing the to-be-monitored battery cells into battery cells of the same group according to a preset grouping rule, and comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result;

and determining the safety monitoring result of the battery cell to be monitored according to the parameter comparison result obtained by comparing the battery cell to be monitored in at least one group.

Optionally, the monitoring parameter information includes at least one monitoring parameter value of the battery cell to be monitored, any one target is grouped, and the step of comparing the monitoring parameter information of each battery cell in the target group to obtain the parameter comparison result includes:

for the parameter values to be compared corresponding to the target grouping in the monitoring parameter values, calculating the central values of the parameter values to be compared of the same items of the battery cells in the target grouping, and determining the normal parameter ranges corresponding to the parameter values to be compared respectively according to the central values;

for any target electric core in the target grouping, comparing any item target parameter value in the to-be-compared parameter values of the target electric core with the corresponding normal parameter range to obtain a range comparison result corresponding to the target parameter value, wherein the range comparison result comprises a result representing whether the target parameter value exceeds the corresponding normal parameter range and/or a result representing the exceeding degree of the target parameter value exceeding the corresponding normal parameter range;

determining a grouping abnormal grade of the target electric core according to the range comparison result corresponding to each parameter value to be compared of the target electric core, and taking the grouping abnormal grade as the parameter comparison result obtained by comparing the target electric core in the target grouping.

Optionally, when each parameter value to be compared of the target electric core includes an electrical parameter value and a temperature parameter value, the step of determining, according to the range comparison result corresponding to each parameter value to be compared of the target electric core, a grouping abnormal level of the target electric core includes:

determining the electrical abnormity grade of the target electric core according to the range comparison result corresponding to each electrical parameter value of the target electric core;

if the electrical abnormity grade is larger than a first preset grade, determining a grouping abnormity grade of the target battery cell according to the electrical abnormity grade and the temperature abnormity grade of the target battery cell, wherein the temperature abnormity grade is determined according to the range comparison result corresponding to the temperature parameter value of the target battery cell;

if the electrical abnormity level is smaller than or equal to the first preset level, determining the grouping abnormity level of the target battery cell according to the electrical abnormity level of the target battery cell.

Optionally, before the step of comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result, the method further includes:

dividing the cells in the same cell string in the cells to be monitored into the same group; and/or the presence of a gas in the gas,

and dividing the cells which are in the same working condition at the same time or the same time period in the cells to be monitored into the same group, wherein the same working condition is the condition that one or more working condition parameters in a fan gear, a charge-discharge state, electric quantity and current magnitude are the same.

Optionally, the monitoring parameter information includes at least one time parameter value obtained by monitoring the electrical core to be monitored at a safety analysis time, and at least one parameter change rate obtained by monitoring at least one historical time period before the safety analysis time;

the step of comparing the monitoring parameter information of each cell in the same group to obtain a parameter comparison result includes:

comparing the time parameter values of each first battery cell in a first group to obtain a first parameter comparison result, wherein the first group is a group consisting of the battery cells which are in the same working condition at the time of the safety analysis in each battery cell to be monitored;

comparing the time parameter values of all the electric cores in a second grouping to obtain a second parameter comparison result, wherein the second grouping is a grouping formed by all the electric cores to be monitored in the electric core string where a first abnormal electric core is located, and the first abnormal electric core is an electric core of which the grouping abnormal grade represented by the first parameter comparison result in each first electric core is greater than a second preset grade;

comparing the parameter change rates of the battery cells in a third group in a historical time period corresponding to the third group to obtain a third parameter comparison result, wherein the third group is a group consisting of the battery cells in the battery cells to be monitored and second abnormal battery cells in the same working condition in the same historical time period, and the second abnormal battery cells are the battery cells in the first abnormal battery cells, wherein the characteristic group abnormal grade of the second parameter comparison result in the first abnormal battery cells is greater than a third preset grade;

comparing the parameter change rates of all the battery cells in a fourth group within the same historical time period to obtain a fourth parameter comparison result, wherein the fourth group is a group formed by all the battery cells to be monitored in a battery cell string in which a third abnormal battery cell is located, and the third abnormal battery cell is a battery cell in which the group abnormal grade represented by the third parameter comparison result in all the second abnormal battery cells is greater than a fourth preset grade;

and comparing the parameter change rates of the cells in the fifth group in each historical period to obtain a fifth parameter comparison result, wherein each fifth group comprises one first abnormal cell.

Optionally, the step of acquiring monitoring parameter information obtained by monitoring each to-be-monitored battery cell in the operation process of the energy storage system includes:

acquiring moment original parameter values of each moment obtained by respectively monitoring each battery cell to be monitored according to a preset monitoring frequency in the running process of an energy storage system;

clustering the time original parameter values of the same items of the battery cores to be monitored at the same time to obtain time clustering center values corresponding to the time original parameter values respectively, and subtracting the corresponding time clustering center values from the time original parameter values to obtain time normalization parameter values respectively;

calculating to obtain a parameter change rate according to the time normalization parameter values of the battery cell to be monitored at each time in a period of time;

and obtaining monitoring parameter information of the battery cell to be monitored at the safety analysis time according to the time normalization parameter value of the battery cell to be monitored at the safety analysis time and the parameter change rate in each historical time period before the safety analysis time.

Optionally, the time normalization parameter value at least includes a time normalization electrical value, and the time normalization electrical value at least includes a time normalization voltage value and a time normalization current value;

the step of calculating a parameter change rate according to the time parameter values of the to-be-monitored battery cell at each time in a period of time includes:

calculating the time normalization power value of the electric core to be monitored according to the time normalization voltage value and the time normalization current value of the electric core to be monitored at the same time;

calculating to obtain the voltage change rate of the battery cell to be monitored in a corresponding time period according to the normalized voltage value of the battery cell to be monitored at each time in a time period;

calculating to obtain the power change rate of the battery cell to be monitored in a corresponding time period according to the moment normalization power values of the battery cell to be monitored in each time period;

and calculating the charge-discharge power difference in a small time period according to the time normalization power values of the battery cell to be monitored at all times in a small time period, and calculating the charge-discharge power difference change rate of the battery cell to be monitored in a corresponding large time period according to the charge-discharge power difference in the small time period in a large time period.

Optionally, the step of determining the safety monitoring result of the electrical core to be monitored according to the parameter comparison result obtained by comparing the electrical core to be monitored in at least one group includes:

and determining a comprehensive abnormal grade of the battery cell to be monitored according to the abnormal grade represented by the parameter comparison result obtained by comparing the battery cell to be monitored in at least one group, and taking the comprehensive abnormal grade as the safety monitoring result of the battery cell to be monitored.

Optionally, after the step of determining the safety monitoring result of the electrical core to be monitored according to the parameter comparison result obtained by comparing the electrical core to be monitored in at least one group, the method further includes:

and when the safety monitoring result representation of the electric core to be monitored needs to perform exception handling on the electric core to be monitored, executing exception handling measures corresponding to the safety monitoring result of the electric core to be monitored, wherein the exception handling measures comprise outputting an early warning prompt and/or cutting off connection.

In order to achieve the above object, the present invention further provides an energy storage system safety monitoring device, which includes:

the acquisition module is used for acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the running process of the energy storage system;

the comparison module is used for comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result for the battery cells which are divided into the same group according to a preset grouping rule in each battery cell to be monitored;

and the determining module is used for determining the safety monitoring result of the electric core to be monitored according to the parameter comparison result obtained by comparing the electric core to be monitored in at least one group.

In order to achieve the above object, the present invention further provides an energy storage system safety monitoring device, including: the energy storage system safety monitoring method comprises a memory, a processor and an energy storage system safety monitoring program which is stored on the memory and can run on the processor, wherein the steps of the energy storage system safety monitoring method are realized when the energy storage system safety monitoring program is executed by the processor.

In addition, to achieve the above object, the present invention further provides a computer readable storage medium, where an energy storage system safety monitoring program is stored, and when the energy storage system safety monitoring program is executed by a processor, the steps of the energy storage system safety monitoring method as described above are implemented.

According to the method and the device, monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the operation process of the energy storage system is acquired, each battery cell to be monitored is divided into battery cells of the same group according to a preset grouping rule, the monitoring parameter information of each battery cell in the same group is compared to obtain a parameter comparison result, and the safety monitoring result of the battery cell to be monitored is determined according to the parameter comparison result obtained by comparing the battery cells to be monitored in at least one group. Compared with the method for comparing the individual temperature values with the threshold values of the battery cells, the method and the device have the advantages that the incidence relation among the battery cells is considered, the battery cells are grouped, the safety monitoring result of the battery cells is determined according to the comparison result of the monitoring parameter information of the battery cells in the same group, the safety state of the battery cells can be determined based on the difference between the monitoring parameter conditions of the battery cells reflected by the monitoring parameter information, the false detection condition can be reduced, and the accuracy of safety monitoring of the energy storage system is improved.

Drawings

FIG. 1 is a schematic diagram of a hardware operating environment according to an embodiment of the present invention;

fig. 2 is a schematic flow chart of a safety monitoring method for an energy storage system according to a first embodiment of the present invention;

fig. 3 is a schematic view of a safety monitoring process according to an embodiment of the present invention;

fig. 4, fig. 5 and fig. 6 are schematic diagrams of three safety monitoring system architectures according to embodiments of the present invention;

fig. 7 is a functional block diagram of a safety monitoring device for an energy storage system according to a preferred embodiment of the invention.

The implementation, functional features and advantages of the objects of the present invention will be further explained with reference to the accompanying drawings.

Detailed Description

It should be understood that the specific embodiments described herein are merely illustrative of the invention and do not limit the invention.

As shown in fig. 1, fig. 1 is a schematic device structure diagram of a hardware operating environment according to an embodiment of the present invention.

It should be noted that, in the embodiment of the present invention, the energy storage system safety monitoring device may be a smart phone, a personal computer, a server, or another device, and is not limited specifically herein.

As shown in fig. 1, the energy storage system safety monitoring device may include: a processor 1001, such as a CPU, a network interface 1004, a user interface 1003, a memory 1005, a communication bus 1002. Wherein a communication bus 1002 is used to enable connective communication between these components. The user interface 1003 may include a Display (Display), an input unit such as a Keyboard (Keyboard), and the optional user interface 1003 may also include a standard wired interface, a wireless interface. The network interface 1004 may optionally include a standard wired interface, a wireless interface (e.g., WI-FI interface). The memory 1005 may be a high-speed RAM memory or a non-volatile memory (e.g., a magnetic disk memory). The memory 1005 may alternatively be a storage device separate from the processor 1001.

Those skilled in the art will appreciate that the device configuration shown in fig. 1 does not constitute a limitation of the energy storage system safety monitoring device and may include more or fewer components than shown, or some components in combination, or a different arrangement of components.

As shown in fig. 1, the memory 1005, which is a kind of computer storage medium, may include therein an operating system, a network communication module, a user interface module, and an energy storage system security monitoring program. The operating system is a program for managing and controlling hardware and software resources of the equipment and supports the running of the energy storage system safety monitoring program and other software or programs. In the device shown in fig. 1, the user interface 1003 is mainly used for data communication with a client; the network interface 1004 is mainly used for establishing communication connection with a server; and the processor 1001 may be configured to call the energy storage system safety monitoring program stored in the memory 1005, and perform the following operations:

for each battery cell to be monitored, dividing the battery cells into the same group according to a preset grouping rule, and comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result;

Further, the operation of grouping any one of the targets, and comparing the monitoring parameter information of each of the cells in the target grouping to obtain the parameter comparison result includes:

for the parameter values to be compared corresponding to the target group in the monitoring parameter values, calculating the central values of the parameter values to be compared of the same items of the battery cells in the target group, and determining the normal parameter ranges corresponding to the parameter values to be compared respectively according to the central values;

Further, when each parameter value to be compared of the target electric core includes an electrical parameter value and a temperature parameter value, the operation of determining the grouping abnormal level of the target electric core according to the range comparison result corresponding to each parameter value to be compared of the target electric core includes:

determining the electrical abnormity grade of the target battery cell according to the range comparison result corresponding to each electrical parameter value of the target battery cell;

and if the electrical abnormity grade is less than or equal to the first preset grade, determining the grouping abnormity grade of the target electric core according to the electrical abnormity grade of the target electric core.

Further, before the operation of comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result, the method further includes:

dividing the battery cells in the same battery cell string in the battery cells to be monitored into the same group; and/or the presence of a gas in the atmosphere,

Further, the monitoring parameter information includes at least one time parameter value obtained by monitoring the electric core to be monitored at the time of safety analysis and at least one parameter change rate obtained by monitoring at least one historical time period before the time of safety analysis;

the operation of dividing the to-be-monitored battery cells into the same group of battery cells according to a preset grouping rule, and comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result includes:

comparing the parameter change rates of all the battery cells in a fourth group within the same historical time period to obtain a fourth parameter comparison result, wherein the fourth group is a group formed by all the battery cells to be monitored in a battery cell string in which a third abnormal battery cell is located, and the third abnormal battery cell is a battery cell in which the group abnormal grade represented by the third parameter comparison result in each second abnormal battery cell is greater than a fourth preset grade;

Further, the operation of acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the operation process of the energy storage system includes:

Further, the time normalization parameter value at least comprises a time normalization electric value, and the time normalization electric value at least comprises a time normalization voltage value and a time normalization current value;

the operation of calculating the parameter change rate according to the time parameter values of the to-be-monitored battery cell at each time in a period of time includes:

calculating the power change rate of the battery cell to be monitored in the corresponding time period according to the time normalization power value of the battery cell to be monitored in each time period;

Further, the operation of determining the safety monitoring result of the to-be-monitored battery cell according to the parameter comparison result obtained by comparing the to-be-monitored battery cell in at least one group includes:

and determining a comprehensive abnormal grade of the battery cell to be monitored according to the abnormal grade represented by a parameter comparison result obtained by comparing the battery cell to be monitored in at least one group, and taking the comprehensive abnormal grade as a safety monitoring result of the battery cell to be monitored.

Further, after the operation of determining the safety monitoring result of the electrical core to be monitored according to the parameter comparison result obtained by comparing the electrical core to be monitored in at least one group, the method further includes:

Based on the structure, various embodiments of the energy storage system safety monitoring method are provided.

Referring to fig. 2, fig. 2 is a schematic flow chart of a safety monitoring method for an energy storage system according to a first embodiment of the present invention.

While a logical order is shown in the flow chart, in some cases, the steps shown or described may be performed in an order different than that shown or described herein. In this embodiment, the execution main body of the energy storage system safety monitoring method may be a device such as a personal computer, a smart phone, a server, etc., and is not limited in this embodiment, and for convenience of description, the explanation of each embodiment by the execution main body is omitted below. In this embodiment, the method for monitoring the safety of the energy storage system includes:

step S10, acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the running process of the energy storage system;

temperature between each electric core in the energy storage system may have certain incidence relation, for example, the temperature between the electric core that the distance is nearer can influence each other, and different operating condition conditions also can cause the influence to the monitoring parameter of electric core, so be in the temperature difference between the electric core of different operating condition conditions probably great, etc.. Therefore, when the safety state of the battery cell is judged based only on the comparison of the individual temperatures of the respective battery cells with the same certain threshold value, there is a high possibility that erroneous judgment may occur. For example, T ° c of the battery cell under one operating condition may be an abnormal temperature, but T ° c of the battery cell under another operating condition may be a normal temperature, so when the threshold is set to T ° c, the battery cell in the normal state is erroneously determined to be in the abnormal state, and the erroneous determination occurs.

In this embodiment, to solve the above problem, when the energy storage system is monitored safely, the electric cells are grouped according to a certain grouping rule, so as to divide the electric cells with the same monitoring parameter status in a normal state into a group, compare the monitoring parameter information of the grouped electric cells, and determine the safety monitoring result of each electric cell based on the comparison result, so as to improve the accuracy of the safety monitoring of the energy storage system.

And taking the battery cell needing to be monitored in the energy storage system as the battery cell to be monitored. For each cell to be monitored, a monitoring device may be provided for monitoring at least one parameter of the cell to be monitored (hereinafter referred to as a monitoring parameter to distinguish). The monitoring parameters may include directly measured parameter items, such as a cell temperature, a cell voltage, a cell current, and the like, or may include parameter items calculated according to the directly measured parameter items, such as a cell power, a change rate of the cell voltage in a period of time, a change rate of the cell temperature in a period of time, and the like, which is not limited in this embodiment. In a specific embodiment, the safety state of the battery cell is determined by monitoring the electrical parameter and combining the monitored temperature information based on the monitored electrical parameter information, which is more accurate than the determination of the safety state of the battery cell only by the temperature information. Different monitoring devices can be adopted for monitoring different monitoring parameters, and the specific implementation mode of the monitoring devices and the setting mode in the energy storage system are not limited in the embodiment.

And in the operation process of the energy storage system, acquiring monitoring parameter information obtained by monitoring each battery cell to be monitored respectively. The monitoring parameter information is specific value information of a monitoring parameter of the battery cell to be monitored, that is, the monitoring parameter information may include at least one monitoring parameter value, for example, when the monitoring parameter includes a temperature, the monitoring parameter information may include a temperature value of the battery cell to be monitored at a certain time.

In a specific embodiment, security analysis may be performed once at intervals (hereinafter, a time at which security analysis is started is referred to as a security analysis time), that is, monitoring parameter information is acquired once at intervals, and security analysis is performed based on the acquired monitoring parameter information; the time interval between two adjacent safety analyses can be set according to the real-time performance of safety monitoring in a specific application scene, and when the real-time performance requirement is high, the time interval can be set to be shorter, for example, analysis is performed every 10 minutes.

It should be noted that the time interval for performing the safety analysis may be different from the time interval for monitoring each monitoring parameter of the battery cell to be monitored. For example, the monitoring parameter value of the electrical core to be monitored is collected once every one minute, and safety analysis is performed once every 10 minutes, so that when safety analysis is performed, the obtained monitoring parameter information may include the monitoring parameter value monitored at the time of safety analysis, or may also include the monitoring parameter value monitored before the time of safety analysis, which is not limited in this embodiment.

Step S20, for the cells to be monitored which are divided into the same group according to a preset grouping rule, comparing the monitoring parameter information of the cells in the same group to obtain a parameter comparison result;

each battery cell to be monitored can be divided into a plurality of groups according to a preset grouping rule, and each group comprises at least one battery cell. In a specific embodiment, the battery cells to be monitored can be grouped in advance, or grouped each time safety analysis is performed, or grouped according to specific conditions of monitoring parameter information after the monitoring parameter information is acquired; the same electric core to be monitored can be divided into only one group or a plurality of groups; when one to-be-monitored battery cell may be divided into a plurality of groups, the to-be-monitored battery cell may be divided into a plurality of groups at the same time, or the to-be-monitored battery cell may be divided into a certain group first, and then whether the to-be-monitored battery cell is divided into other groups is determined according to the parameter comparison result of the to-be-monitored battery cell in the group. The grouping rule and the grouping timing are not limited in this embodiment.

In a specific embodiment, the grouping rule may be set according to monitoring parameters to be monitored, so that when grouping is performed according to the grouping rule, the cells to be monitored, whose monitoring parameter conditions are at the same level in a normal state, may be allocated to the same group, and thus the safety state of each cell may be determined based on the comparison result of the monitoring parameter information of the cells in the group.

For each battery cell divided into the same group (here, "each" does not limit that there are multiple battery cells in one group), the monitoring parameter information of each battery cell may be compared, and the result obtained by the comparison is referred to as a parameter comparison result for distinction. It can be understood that, if a certain monitoring parameter condition is consistent when a plurality of battery cells are in a normal state, when the monitoring parameter condition of a certain battery cell is greatly different from that of other battery cells, it may be considered that the battery cell is possibly abnormal and may be in an abnormal state; if the monitoring parameter conditions of a certain battery cell at different times (or time intervals) are consistent in a normal state, it can be considered that the battery cell may be abnormal when the monitoring parameter conditions at a certain time are greatly different from those at other times. The purpose of comparing the monitoring parameter information of each battery cell is to determine the difference between the monitoring parameter information of each battery cell, so as to determine whether an abnormal battery cell exists according to the difference. When a group includes a plurality of cells, comparing the monitoring parameter information of each cell may specifically include comparing the same monitoring parameter value of the same cell at different times or time periods (hereinafter referred to as longitudinal comparison), or comparing the same monitoring parameter value of different cells at the same time or time periods (hereinafter referred to as transverse comparison); when a cell is included in a group, the cells may be longitudinally compared. In the following description, various comparison methods are available to achieve the above-mentioned comparison purpose, and the present embodiment is not limited thereto. The form of the parameter comparison result obtained by the comparison may also be set as needed, which is not limited in this embodiment, and for example, the parameter comparison result representing whether each electrical core is an abnormal electrical core may be obtained by the comparison.

For example, in an embodiment, for any one of the cells in any one of the groups, for a parameter value to be compared corresponding to the group among the monitoring parameter values, it is determined whether a difference between at least one of the cells in the group and the cell is greater than a certain threshold, and if the difference exists, it may be determined that the cell is in an abnormal state in a parameter comparison result of the cell in the group.

In a specific embodiment, the monitoring parameter information of each to-be-monitored battery cell may be represented in a matrix form, and when the to-be-monitored battery cells are grouped, the monitoring parameter information of each to-be-monitored battery cell that is grouped may be extracted from the matrix and represented by a new matrix, so as to improve the calculation efficiency.

And S30, determining the safety monitoring result of the battery cell to be monitored according to the parameter comparison result obtained by comparing the battery cell to be monitored in at least one group.

After comparing the groups, for each to-be-monitored battery cell, the safety monitoring result of the to-be-monitored battery cell may be determined according to a parameter comparison result obtained by comparing the to-be-monitored battery cell in at least one group. In a specific embodiment, when the battery cell to be monitored is divided into a plurality of groups, determining a safety monitoring result of the battery cell to be monitored according to a parameter comparison result obtained by comparing the battery cell to be monitored in one or more of the groups; and when the electric core to be monitored is only divided into one group, determining the safety monitoring result of the electric core to be monitored according to the parameter comparison result obtained by comparing the electric core to be monitored in the group.

The safety monitoring result may specifically be a result representing whether the electric core to be monitored is an abnormal electric core, or may also be a result representing an abnormal degree of the electric core to be monitored. In the specific embodiment, the setting may be according to the requirement of a specific application scenario, and is not limited in this embodiment.

Further, in a specific embodiment, after obtaining the safety monitoring results of the electric cores to be monitored, the safety monitoring results of the electric cores to be monitored may be output, for example, output in a form of a report, or corresponding exception handling measures may be executed for an abnormal electric core, or corresponding exception handling measures may be executed for electric cores of different exception levels. The embodiment is not particularly limited.

Compared with the method for comparing the individual temperature value with the threshold value of each battery cell, the embodiment considers the incidence relation among the battery cells, and the battery cells are grouped, so that the safety monitoring result of the battery cells is determined according to the comparison result of the monitoring parameter information of the battery cells in the same group, the safety state of the battery cells can be determined based on the difference among the monitoring parameter conditions of the battery cells reflected by the monitoring parameter information, the false detection condition can be reduced, and the accuracy of the safety monitoring of the energy storage system is improved.

In addition, in a specific embodiment, the safety state of the battery cell can be analyzed and judged from a plurality of dimensions and angles, such as temperature, voltage and power, so that the safety state of the battery cell can be accurately known without detecting the internal condition of the battery cell, and the safety state of the battery cell can be predicted more accurately.

Further, in an embodiment, before the step S20, the method further includes:

step S40, dividing the cells in the same cell string in the cells to be monitored into the same group;

in the present embodiment, two grouping rules are provided, and in the specific implementation process, one or two of the two rules may be optionally implemented as needed.

The first grouping rule is to divide the cells in the same cell string into the same group, that is, each cell string is in one group. Wherein, each electric core in same electric core cluster is series connection, and the monitoring parameter situation of each electric core is in same level under normal conditions, if the inside of certain electric core in the electric core cluster appears unusually for example takes place the internal short circuit, its monitoring parameter situation will appear differently with other normal electric cores, so will be in the electric core of same electric core cluster and divide to same group, can judge the safe state of each electric core through the contrast result of the monitoring parameter information of each electric core in the same electric core cluster.

And S50, dividing the cells to be monitored, which are under the same working condition at the same time or the same time interval, into the same group, wherein the same working condition is the condition that one or more working condition parameters of a fan gear, a charge-discharge state, electric quantity and current magnitude are the same.

The second grouping rule is to divide the cells under the same working condition at the same time or in the same time period into the same group, where the time may specifically be a safety analysis time, or a time before the safety analysis time, and may specifically be set as required. The fan gear of considering electric core, operating mode conditions such as charge-discharge state are different, the monitoring parameter situation of electric core may be in different levels, the electric core that second grouping rule will be in same operating mode condition at the same moment or in the same period of time divides to same group, when the inside of certain electric core appears unusually in same group for example takes place the internal short circuit, its monitoring parameter situation will appear differently with other normal electric cores, so will be in same working mode condition's electric core at the same moment or in the same period of time and divide to same group, can judge the safe state of each electric core through the contrast result of the monitoring parameter information of each electric core of same working condition.

In a specific embodiment, the same operating condition may be set as a condition that one or more operating parameters of a fan gear, a charge-discharge state, an electric quantity and a current magnitude are the same. For example, in one embodiment, the fan position, the charge-discharge state, the charge amount, and the current amount may be considered to be in the same operating condition at the same time. The working conditions of each battery cell at each moment or each time interval can be additionally monitored. The fan gear is the gear that is arranged in the energy storage system to carry out the fan of cooling to electric core, and its wind strength is different for different gears representation, and the cooling effect is different. Different fans may have different gears.

In a specific embodiment, each to-be-monitored electric core can be grouped according to the first grouping rule and the second grouping rule, and when the safety monitoring result of the electric core is determined based on the parameter comparison result of the electric core in the two groups, the abnormal condition in the electric core can be checked from two dimensions, so that the monitoring result is more accurate.

Further, in an embodiment, after the step S30, the method further includes:

step S60, when the safety monitoring result representation of the electric core to be monitored needs to perform exception handling on the electric core to be monitored, executing exception handling measures corresponding to the safety monitoring result of the electric core to be monitored, wherein the exception handling measures comprise outputting an early warning prompt and/or cutting off connection.

The safety monitoring result of the battery cell to be monitored may indicate that the battery cell to be monitored is normal or abnormal, and an abnormal handling measure corresponding to the safety monitoring result may be set for the safety monitoring result representing that the battery cell to be monitored is abnormal, for example, the abnormal handling measure may include outputting an early warning prompt message and/or cutting off connection; different safety monitoring results can correspond different exception handling measures, for example when the safety monitoring result indicates that the abnormal degree of electric core is lighter, the exception handling measure can be output early warning suggestion to make the staff investigate unusual electric core, if, when the safety monitoring result indicates that the abnormal degree of electric core is more serious, the exception handling measure can be the excision connection, in order to avoid electric core to continue work and lead to the emergence of conflagration.

Further, in an embodiment, as shown in fig. 3, the monitoring parameter information may include time electrical parameters (a time voltage value, a time current value, and/or a time power value) and/or a time temperature value of the battery cell at the safety analysis time, and may further include an electrical parameter change rate (a voltage change rate, a current change rate, a power change rate, and/or a charge-discharge power difference change rate) and/or a temperature change rate of the battery cell at each historical time period before the safety analysis time. Can be according to electric core cluster with electric core to divide into groups, can also divide into groups electric core according to operating mode condition, synthesize according to the comparison result of various groups and confirm the security state (or being called the safety monitoring result) of waiting to monitor electric core, carry out the early warning or carry out the precaution according to the security state.

Further, in a specific embodiment, each to-be-monitored electric core may be numbered, the number may represent an electric core string where the to-be-monitored electric core is located, and the number of the to-be-monitored electric core and the corresponding monitoring parameter information are stored in an associated manner, so that the monitoring parameter information of each to-be-monitored electric core is conveniently distinguished and processed.

Further, based on the first embodiment, a second embodiment of the method for monitoring safety of an energy storage system according to the present invention is provided, where in this embodiment, the step S20 of grouping any one object, and comparing the monitoring parameter information of each battery cell in the object grouping to obtain the parameter comparison result includes:

step S201, for the parameter values to be compared corresponding to the target grouping in the monitoring parameter values, calculating the central values of the parameter values to be compared of the same items of each battery cell in the target grouping, and determining the normal parameter ranges corresponding to the parameter values to be compared respectively according to the central values;

in this embodiment, the monitoring parameter information may include at least one monitoring parameter value of the battery cell to be monitored. It should be explained that specific values of different monitoring parameters are referred to as different monitoring parameter values, different values of the same monitoring parameter belong to the same monitoring parameter value, for example, a temperature value and a voltage value of a cell are different monitoring parameter values, two temperature values of the same cell at different times are the same monitoring parameter values, and temperature values of two cells at the same time are also the same monitoring parameter values.

In a specific implementation manner, monitoring parameter items to be compared of the groups obtained by dividing according to different grouping rules may be different, and for any one of the groups obtained by dividing (hereinafter referred to as a target group), a monitoring parameter value to be compared of the target group among the monitoring parameter values is taken as a parameter value to be compared.

And calculating the central value of the parameter value to be compared of each battery cell with the same item in the target grouping. In a specific embodiment, only one battery cell may be in a target group, and at this time, center values of multiple parameter values to be compared of the same item of the battery cell may be calculated, for example, center values of voltage change rates of the battery cell in different time periods are calculated; or there may be multiple cells in the target group, at this time, the central value of the parameter value to be compared of the same item of the multiple cells may be calculated, for example, the central value of the voltage value of the multiple cells at a certain time is calculated.

The central value of the plurality of parameter values to be compared is a value representing a central level of the plurality of parameter values to be compared, and there are many ways to calculate the central value of the plurality of parameter values to be compared in the specific embodiment, which is not limited in this embodiment. For example, a K-means clustering algorithm may be used for clustering, and the number of clusters may be set to 1, so as to obtain a cluster center value.

According to the calculated central value of a parameter value to be compared, a range corresponding to the parameter value to be compared can be determined, the range is used for representing the normal level of the parameter value to be compared in the group, and the range is referred to as a normal parameter range for distinguishing. The determining the normal parameter range according to the central value may specifically be to float the central value by a certain value to obtain the normal parameter range, and the floating value may be set according to experience.

In other embodiments, the parameter comparison may not be performed for the first time during a period of time in which the energy storage system is started to operate, and in this time, for the parameter values to be compared corresponding to the target group among the monitoring parameter values, a range formed by the maximum value and the minimum value of the parameter values to be compared of the same item of each battery cell in the target group is used as a normal parameter range corresponding to the parameter value to be compared of each battery cell in the target group when the safety analysis is performed in the subsequent time period.

Step S202, for any target electric core in the target grouping, comparing any item target parameter value in the to-be-compared parameter values of the target electric core with the corresponding normal parameter range to obtain a range comparison result corresponding to the target parameter value, wherein the range comparison result comprises a result representing whether the target parameter value exceeds the corresponding normal parameter range and/or a result representing the exceeding degree of the target parameter value exceeding the corresponding normal parameter range;

for any cell in the target grouping (hereinafter referred to as a target cell for distinction), comparing any parameter value to be compared (hereinafter referred to as a target parameter value for distinction) in the parameter values to be compared of the target cell with the corresponding normal parameter range to obtain a comparison result (hereinafter referred to as a range comparison result for distinction). For example, the temperature value of the target battery cell is compared with the normal temperature range to obtain a range comparison result, and the voltage value of the target battery cell is compared with the normal voltage range to obtain a range comparison result.

In a specific implementation manner, according to specific needs, the range comparison result may be set to include a result indicating whether the target parameter value exceeds the corresponding normal parameter range, or a result indicating an extent to which the target parameter value exceeds the corresponding normal parameter range, or include both a result indicating whether the target parameter value exceeds the corresponding normal parameter range and a result indicating an extent to which the target parameter value exceeds the corresponding normal parameter range, which is not limited in this embodiment.

Step S203, determining a grouping abnormal grade of the target electric core according to the range comparison result corresponding to each parameter value to be compared of the target electric core, and taking the grouping abnormal grade as the parameter comparison result obtained by comparing the target electric core in the target grouping.

After obtaining the range comparison results corresponding to the parameter values to be compared of the target electric core, the abnormal grade of the target electric core (hereinafter referred to as a grouping abnormal grade to show differentiation) may be determined according to the range comparison results. In a specific embodiment, a manner of determining the packet exception level according to the range comparison result may be set as needed, and is not limited in this embodiment. It can be understood that, when the target electric core does not exceed the value of the parameter to be compared in the corresponding normal parameter range, the grouping abnormal grade is generally the lowest grade, that is, the result obtained by comparing in the target grouping indicates that the target electric core has no abnormality; when the number of parameter values to be compared of the target electric core exceeding the corresponding normal parameter range is more, the abnormal grade of the target electric core is generally higher; when the exceeding degree of the parameter value to be compared of the target battery cell exceeding the corresponding normal parameter range is larger, the abnormal grade of the target battery cell is generally higher.

Further, in an embodiment, the step S30 includes:

step S301, determining a comprehensive abnormal grade of the electric core to be monitored according to an abnormal grade represented by a parameter comparison result obtained by comparing the electric core to be monitored in at least one group, and taking the comprehensive abnormal grade as a safety monitoring result of the electric core to be monitored.

When the parameter comparison result obtained by comparing the electric cores to be monitored in groups can represent the abnormal grade of the electric core to be monitored, for example, when the parameter comparison result is the abnormal grade of the electric core to be monitored in groups, the final abnormal grade of the electric core to be monitored (hereinafter referred to as comprehensive abnormal grade for distinguishing) can be determined according to the parameter comparison result obtained by comparing the electric core to be monitored in at least one group, and the comprehensive abnormal grade is used as the safety monitoring result of the electric core to be monitored. In a specific embodiment, a mode of determining the comprehensive abnormal level according to the parameter comparison result may be set as needed, and is not limited in this embodiment. It can be understood that, when the anomaly level of the battery cell to be monitored represented by the parameter comparison result is higher, the comprehensive anomaly level of the battery cell to be monitored is generally higher.

Further, in an embodiment, the step S203 includes:

step S2031, determining an electrical abnormal grade of the target electric core according to the range comparison result corresponding to each electrical parameter value of the target electric core;

in consideration of the fact that the safety state of the battery cell is judged more accurately directly according to the electrical parameter value, the temperature anomaly is only a phenomenon that the internal anomaly of the battery cell shows, and the safety state of the battery cell is judged only according to the temperature, and the situation that false detection may be caused is judged.

Specifically, the abnormality level of the target battery cell (hereinafter referred to as an electrical abnormality level for distinction) may be determined according to the range comparison result corresponding to each electrical parameter value of the target battery cell. In a specific embodiment, a manner of determining the electrical abnormality level according to the range comparison result may be set as needed, and is not limited in this embodiment. It can be understood that, when the target electric core does not exceed the electrical parameter value corresponding to the normal parameter range, the electrical anomaly level thereof is generally the lowest level, that is, it means that the result obtained by comparing the electrical parameter values in the target grouping is that the target electric core has no anomaly; when the number of the electric parameter values of the target electric core exceeding the corresponding normal parameter range is more, the abnormal grade of the target electric core is generally higher; when the electrical parameter value of the target battery cell exceeds the corresponding normal parameter range to a greater extent, the abnormal level of the target battery cell is generally higher.

Step S2032, if the electrical anomaly level is greater than a first preset level, determining a grouping anomaly level of the target electric core according to the electrical anomaly level and a temperature anomaly level of the target electric core, wherein the temperature anomaly level is determined according to the range comparison result corresponding to the temperature parameter value of the target electric core;

the temperature parameter values of the battery cells in the target group may be compared to obtain a range comparison result corresponding to the temperature parameter values, and the temperature abnormality level of the target battery cell is determined according to the range comparison result, where the specific determination manner is not limited in this embodiment.

If the electrical abnormity level of the target battery cell is greater than the first preset level, the grouping abnormity level of the target battery cell can be determined according to the electrical abnormity level and the temperature abnormity level of the target battery cell. The first preset level may be set as needed, and when the electrical anomaly level is greater than the first preset level, it indicates that the target electric core may be in an abnormal state. The determining of the grouping abnormality level of the target battery cell according to the electrical abnormality level and the temperature abnormality level may specifically be adding the two levels or adding the two levels according to a certain weight, for example, if the electrical abnormality level is 3, and the temperature abnormality level is 3, then the grouping abnormality level may be 6.

Step S2033, if the electrical anomaly level is less than or equal to the first preset level, determining a grouping anomaly level of the target electrical core according to the electrical anomaly level of the target electrical core.

If the electrical anomaly level is less than or equal to the first preset level, it is indicated that the target battery cell may be in a normal state, in this case, the temperature of the target battery cell does not need to be compared, and the grouping anomaly level of the target battery cell is directly determined according to the electrical anomaly level, for example, the electrical anomaly level is directly used as the grouping anomaly level, or is multiplied by a certain proportion and then used as the grouping anomaly level.

In an embodiment, when it is determined that the electrical abnormality level of each battery cell in the target grouping does not exceed the first preset level, the comparison of the temperature parameter values of each battery cell in the target grouping is not performed, so as to save the calculation resources.

Further, based on the first and/or second embodiments, a third embodiment of the method for monitoring safety of an energy storage system according to the present invention is provided, in this embodiment, the step S20 includes:

step S204, comparing the time parameter values of each first electric core in a first group to obtain a first parameter comparison result, wherein the first group is a group consisting of the electric cores which are in the same working condition at the time of the safety analysis in each electric core to be monitored;

in this embodiment, the monitoring parameter information of the to-be-monitored battery cell may include at least one monitoring parameter value obtained by monitoring the to-be-monitored battery cell at the safety analysis time (hereinafter, referred to as a time parameter value for distinction), and may further include at least one monitoring parameter value (hereinafter, referred to as a parameter change rate) representing a change rate obtained by monitoring the to-be-monitored battery cell at least one historical period before the safety analysis time, for example, a voltage change rate, a temperature change rate, a power change rate, and the like. The time parameter value represents a result of the safety state of the battery cell at the safety analysis time, that is, whether the battery cell is normal or abnormal at the safety analysis time can be reflected, and the parameter change rate represents a change process of the safety state of the battery cell before the safety analysis time, that is, a process that the battery cell is changed from the normal state to the abnormal state before the safety analysis time can be reflected. In this embodiment, when the time parameter value and the parameter change rate are combined to determine the safety state of the battery cell, not only can the obvious abnormality of the battery cell at the time of the safety analysis be monitored according to the time parameter value, but also the abnormal condition that the battery cell is not obviously shown at the time of the safety analysis can be found as early as possible according to the parameter change rate, so that the safety protection measure can be performed as early as possible, and the situation that cannot be compensated due to the delayed discovery of the abnormal condition can be avoided.

It should be noted that the voltage value, the current value, the power value and the corresponding change rate are all electrical parameter values, and the temperature value and the corresponding change rate are all temperature parameter values.

In this embodiment, the cells in the same working condition at the time of the safety analysis in each cell to be monitored may be divided into the same group, which is hereinafter referred to as a first group for distinction. The specific setting manner of the same working condition is not limited in this embodiment.

There may be a plurality of first packets, and for each first packet, time parameter values of the cells (hereinafter referred to as first cells for distinction) in the first packet are compared to obtain a parameter comparison result (hereinafter referred to as first parameter comparison result for distinction). That is, the parameter value to be compared corresponding to the first packet is the time parameter value. In a specific implementation manner of comparing the time parameter values of the battery cores to obtain the first parameter comparison result, reference may be made to the above-mentioned embodiment, which is not described herein again.

Step S205, comparing the time parameter values of each electric core in a second grouping to obtain a second parameter comparison result, wherein the second grouping is a grouping formed by each electric core to be monitored in an electric core string in which a first abnormal electric core is positioned, and the first abnormal electric core is an electric core of which the grouping abnormal grade represented by the first parameter comparison result in each first electric core is greater than a second preset grade;

and the battery cell with the grouping abnormal grade represented by the first parameter comparison result in each first battery cell larger than the second preset grade is called a first abnormal battery cell. It should be explained that the packet exception level represented by the first parameter comparison result means that the first parameter comparison result itself may be a packet exception level, or may be a result that can be used to determine the packet exception level, which is not limited in this embodiment.

Wherein the second preset level can be set as required. When the grouping abnormal grade represented by the first parameter comparison result of the first electric core is greater than the second preset grade, the first electric core shows an abnormality in the electric core which is in the same working condition at the time of safety analysis, at this time, the first electric core can be further divided into other groups, and whether the first electric core is really abnormal or the abnormal degree of the first electric core is further determined by combining the parameter comparison results of the other groups; when the grouping abnormal grade represented by the first parameter comparison result of the first electric core is less than or equal to the second preset grade, it is indicated that the first electric core does not show abnormality in the electric cores under the same working condition at the time of safety analysis, and at this time, it can be determined that the first electric core is in a normal state, or at least no abnormal early warning or other protection measures are performed on the first electric core at present, so that no serious consequences can be caused.

There may be a plurality of first abnormal cells (or one or none), and for each first abnormal cell, the cells to be monitored in the cell string in which the first abnormal cell is located may be divided into a group (hereinafter referred to as a second group for distinction).

In a specific embodiment, for each of the cells in the first cell other than the first abnormal cell, the safety monitoring result may be directly determined according to the first parameter comparison result and the following fifth parameter comparison result.

There may be a plurality of second grouping, and for each second grouping, the time parameter values of the battery cells in the second grouping may be compared to obtain a parameter comparison result (hereinafter referred to as a second parameter comparison result to illustrate the distinction). That is, the parameter value to be compared corresponding to the second grouping is the time parameter value. The specific implementation of comparing the time parameter values of each electrical core to obtain the second parameter comparison result may refer to the above embodiment, which is not described herein again.

Step S206, comparing the parameter change rates of the electric cores in a third group in a historical time period corresponding to the third group to obtain a third parameter comparison result, wherein the third group is a group consisting of the electric cores in the same historical time period and under the same working condition with a second abnormal electric core in each electric core to be monitored, and the second abnormal electric core is an electric core in each first abnormal electric core, wherein the represented group abnormal grade of the second parameter comparison result is greater than a third preset grade;

and the battery cell with the grouping abnormal grade represented by the second parameter comparison result in each first abnormal battery cell and larger than the third preset grade is called a second abnormal battery cell. It should be explained that the packet exception level characterized by the second parameter comparison result means that the second parameter comparison result itself may be the packet exception level, or may be a result that can be used to determine the packet exception level.

Wherein the third preset level can be set as required. When the grouping abnormal grade represented by the second parameter comparison result of the first abnormal electric core is greater than a third preset grade, the first abnormal electric core is indicated to be abnormal in the electric cores of the same electric core string at the safety analysis moment, the possibility that the first abnormal electric core is abnormal can be determined to be higher, at this time, the first abnormal electric core can be further divided into other groups, and whether the first abnormal electric core is abnormal or not is determined or the abnormal degree of the first abnormal electric core is further determined by combining the parameter comparison results of the other groups; when the grouping anomaly level represented by the second parameter comparison result of the first abnormal cell is less than or equal to a third preset level, it is indicated that the first abnormal cell does not show an anomaly in the cells of the same cell string at the time of safety analysis, and it can be determined that the first abnormal cell is in an abnormal state with a lower level or has a low degree of severity, or at least that only lower-level early warning measures are performed on the first abnormal cell at present, and no serious consequence is caused, so that, under such a condition, subsequent grouping and comparative analysis may not be performed on the first abnormal cell, and the waste of calculation resources is avoided.

There may be a plurality of second abnormal cells (or one or none), and for each second abnormal cell, the cells which are in the same working condition with the second abnormal cell in the same history period may be divided into the same group (hereinafter referred to as a third group for distinction). For example, assuming that a day before the safety analysis time is divided into 24 time periods, the second abnormal cell is divided into 24 third groups, and each third group corresponds to one time period.

In a specific embodiment, for each of the cells other than the second abnormal cell in the first abnormal cell, the safety monitoring result may be directly determined according to the first parameter comparison result, the second parameter comparison result, and the following fifth parameter comparison result.

There may be a plurality of third groups, and for each third group, the parameter change rates of the cells in the third group in the history period corresponding to the third group may be compared to obtain a parameter comparison result (hereinafter, referred to as a third parameter comparison result to show differentiation). That is, the parameter value to be compared corresponding to the third packet is the parameter change rate. The specific implementation of comparing the parameter change rates of the battery cells to obtain the third parameter comparison result may refer to the foregoing embodiment, which is not described herein again.

Step S207, comparing the parameter change rates of the battery cells in a fourth group in the same historical time period to obtain a fourth parameter comparison result, where the fourth group is a group formed by the battery cells to be monitored in the battery cell string in which a third abnormal battery cell is located, and the third abnormal battery cell is a battery cell in which the group abnormal level represented by the third parameter comparison result in each second abnormal battery cell is greater than a fourth preset level;

and the battery cell with the grouping abnormal grade represented by the third parameter comparison result in each second abnormal battery cell larger than the fourth preset grade is used as a third abnormal battery cell. It should be explained that the packet exception level represented by the third parameter comparison result means that the third parameter comparison result itself may be the packet exception level, or may be a result that can be used to determine the packet exception level.

Wherein, the fourth preset level can be set according to the requirement. When the grouping abnormal grade represented by the third parameter comparison result of the second abnormal electric core is greater than the fourth preset grade, the second abnormal electric core is also abnormal in the electric core under the same working condition in the corresponding historical time period, and the second abnormal electric core can be determined to be abnormal in the historical time period, so that the possibility that the second abnormal electric core is abnormal is higher or the abnormal degree is higher, at the moment, the second abnormal electric core can be further divided into other groups, and whether the second abnormal electric core is abnormal or the abnormal degree of the second abnormal electric core is further determined by combining the parameter comparison results of the other groups; when the grouping abnormal grade represented by the third parameter comparison result of the second abnormal electric core is less than or equal to the fourth preset grade, it is indicated that the second abnormal electric core does not show abnormality in the electric cores under the same working condition in the corresponding historical time period, the abnormal time is not long, the abnormal degree is not particularly high, at this time, the second abnormal electric core can be determined to be in the abnormal state of the medium grade, or at least, only the medium-grade early warning or protection measures are required to be performed on the second abnormal electric core at present, and no serious consequence is caused, so that in this case, subsequent grouping and comparative analysis can not be performed on the second abnormal electric core, and the waste of calculation resources is avoided.

There may be a plurality of (one or none) third abnormal cells, and for each third abnormal cell, the cells in the cell string in which the third abnormal cell is located may be divided into a group (hereinafter, referred to as a fourth group for distinction).

In a specific embodiment, for each of the cells other than the third abnormal cell in the second abnormal cell, the safety monitoring result may be determined according to the first parameter comparison result, the second parameter comparison result, the third parameter comparison result, and the following fifth parameter comparison result.

There may be a plurality of fourth groups, and for each fourth group, the parameter change rates of the cells in the fourth group in the same history period may be compared to obtain a parameter comparison result (hereinafter referred to as a fourth parameter comparison result to indicate distinction). That is, the parameter value to be compared corresponding to the fourth group is the parameter change rate. The specific implementation of comparing the parameter change rates of the battery cells to obtain the fourth parameter comparison result may refer to the above embodiments, which are not described herein again. For example, if a day before the safety analysis time is divided into 24 periods, the parameter change rates in the 24 periods are respectively compared to obtain fourth parameter comparison results in the 24 periods.

For the third abnormal cell, the safety monitoring result can be determined according to the first parameter comparison result, the second parameter comparison result, the third parameter comparison result, the fourth parameter comparison result and the following fifth parameter comparison result.

Step S208, comparing the parameter change rates of the cells in a fifth group in each historical period to obtain a fifth parameter comparison result, where each fifth group includes one first abnormal cell.

Each first abnormal cell is individually divided into a group, which is hereinafter referred to as a fifth group for distinction, that is, each fifth group includes only one first abnormal cell. And comparing the parameter change rates of the cells in the fifth group in each historical time period to obtain a parameter comparison result (hereinafter referred to as a fifth parameter comparison result to show differentiation). That is, the parameter value to be compared corresponding to the fifth group is the parameter change rate. The specific implementation of comparing the parameter change rates of the battery cells to obtain the fifth parameter comparison result may refer to the above embodiments, which are not described herein again.

When the grouping abnormal grade represented by the fifth parameter comparison result of the first abnormal electric core is greater than a certain grade, the difference of the parameter change rates of the first abnormal electric core in different historical periods is shown, the higher the possibility of abnormality or the higher the abnormal degree is shown, and the more accurate safety monitoring result of the first abnormal electric core can be obtained by combining the fifth parameter comparison result.

Further, based on the first, second and/or third embodiments, a fourth embodiment of the method for monitoring safety of an energy storage system according to the present invention is provided, and in this embodiment, the step S10 includes:

step S101, acquiring time original parameter values of each time obtained by respectively monitoring each battery cell to be monitored according to a preset monitoring frequency in the operation process of an energy storage system;

in this embodiment, at least one parameter value (hereinafter referred to as an original time parameter value) of each to-be-monitored battery cell at each time, such as a voltage value, a temperature value, a current value, and the like at each time, obtained by directly measuring each to-be-monitored battery cell according to a preset monitoring frequency during the operation of the energy storage system, may be used. The preset monitoring frequency may be set as needed, and is not limited in this embodiment.

Step S102, clustering the time original parameter values of the same items of the battery cells to be monitored at the same time to obtain time clustering center values corresponding to the time original parameter values respectively, and subtracting the corresponding time clustering center values from the time original parameter values to obtain time normalization parameter values respectively;

in other embodiments, the original parameter value at the time may be directly used as the monitoring parameter information to participate in the subsequent comparison.

In this embodiment, in order to save computing resources and improve the speed of security analysis, the original parameter values at the moment may be normalized.

Specifically, the time original parameter values of the cells to be monitored at the same time and the same item can be clustered to obtain time clustering center values corresponding to the time original parameter values respectively. For example, when the time original parameter values of the to-be-monitored battery cells include a temperature value and a voltage value, clustering the temperature values of the to-be-monitored battery cells at the same time, dividing the temperature values of the to-be-monitored battery cells at the time into a plurality of clusters, where each cluster corresponds to one cluster center value, and taking the cluster center value of the cluster to which the temperature value of the to-be-monitored battery cell at the time belongs as the time cluster center value corresponding to the temperature value. The voltage values are also clustered in this manner.

The cluster number of the cluster may be set as needed, or may not be set, and the cluster number is determined according to the specific clustering performance of the original parameter value at each time in the clustering process, which is not limited in this embodiment.

And respectively subtracting the corresponding time clustering center value from each time original parameter value to obtain a time normalization parameter value. For example, a cluster center value obtained by clustering the temperature values of the cells to be monitored at a certain time is subtracted from the temperature value of the certain cell at the certain time, so as to obtain a normalized temperature value of the cell at the certain time.

Step S103, calculating to obtain a parameter change rate according to the moment normalization parameter values of the battery cell to be monitored at each moment in a period;

and calculating the parameter change rate of the battery cell to be monitored in a period according to the normalized parameter values of the battery cell to be monitored at all times in the period. In a specific embodiment, the parameter change rate corresponding to the time normalization parameter value of the to-be-monitored electric core in a certain time period can be calculated according to the time normalization parameter value of the to-be-monitored electric core at the same time in the certain time period; or, after another new parameter value of the electrical core to be monitored at a certain time is calculated according to several time normalization parameter values of the electrical core to be monitored at the same time in a certain time period, the parameter change rate corresponding to the new parameter value of the electrical core to be monitored in the certain time period is calculated according to the new parameter value of the electrical core to be monitored at each time in the certain time period.

Step S104, obtaining monitoring parameter information of the electric core to be monitored at the safety analysis time according to the time normalization parameter value of the electric core to be monitored at the safety analysis time and the parameter change rate in each historical time period before the safety analysis time.

And obtaining the monitoring parameter information of the battery cell to be monitored at the safety analysis moment according to the normalized parameter value of the battery cell to be monitored at the safety analysis moment and the parameter change rate in each historical time period before the safety analysis moment. The time normalization power value of the cell to be monitored at the safety analysis time may be directly used as the monitoring parameter value in the monitoring parameter information, or may be obtained by calculating a new parameter value according to several time normalization parameter values of the cell to be monitored at the safety analysis time, and then using the new parameter value as the monitoring parameter value in the monitoring parameter information, for example, by multiplying the time normalization voltage value and the time normalization current value of the cell to be monitored at the safety analysis time to obtain the time normalization power value of the cell to be monitored at the safety analysis time.

It should be noted that, because the number of abnormal cells in the energy storage system is generally very small, and the difference between the original parameter values of each cell at the same time is generally small, after the normalization processing is performed on the original parameter values of each cell at the same time, the normalized parameter values of most cells at the same time may be 0 or close to 0, so that the calculation amount can be greatly reduced during the subsequent comparison. In an embodiment, after subtracting the corresponding time clustering center value from the time original parameter value, it may be determined whether the result is within a certain range, and if the result is within the range, the time normalization parameter value corresponding to the time original parameter value is set to 0, so as to further reduce the amount of calculation and improve the efficiency of security analysis; the range can be set as required, so that when the time original parameter value minus the corresponding time clustering center value is in the range, the difference between the time original parameter value and the time clustering center value is considered to be very small, and when the corresponding time normalization parameter value is set to be 0, the subsequent grouping comparison can not be greatly influenced.

Further, in an embodiment, the step S103 includes:

step S1031, calculating a time normalization power value of the electric core to be monitored according to the time normalization voltage value and the time normalization current value of the electric core to be monitored at the same time;

in this embodiment, the time normalization parameter value may include at least a time normalization electrical value, and the time normalization electrical value includes at least a time normalization voltage value and a time normalization current value. The time normalization power value of the battery cell to be monitored at the same time can be obtained by calculating according to the time normalization voltage value and the time normalization current value of the battery cell to be monitored at the same time. The charging and discharging states of the battery cell can be distinguished according to the positive and negative of the current, and the calculated time normalization power value may be a charging power value or a discharging power value. When comparing, the charging power value and the discharging power value can be regarded as monitoring parameter values of different items.

Step S1032, calculating a voltage change rate of the to-be-monitored electric core in a corresponding time period according to the time normalization voltage values of the to-be-monitored electric core at each time in the time period;

and calculating the voltage change rate of the cell to be monitored in the time period according to the normalized voltage value of the cell to be monitored at each moment in the time period. The voltage change rate of the battery cell to be monitored in a plurality of time periods can be calculated according to the requirement.

Step S1033, calculating a power change rate of the battery cell to be monitored in a corresponding time period according to the time normalization power values of the battery cell to be monitored in each time period;

and calculating the power change rate of the battery cell to be monitored in a time period according to the normalized power value of the battery cell to be monitored at each moment in the time period. The power change rate of the battery cell to be monitored in a plurality of time periods can be calculated according to the requirement. Likewise, the power change rate may also include a charge power change rate and a discharge power change rate.

Step S1034, calculating the charge-discharge power difference in a small time interval according to the time normalization power value of the cell to be monitored at each time in the small time interval, and calculating the charge-discharge power difference change rate of the cell to be monitored in a corresponding large time interval according to the charge-discharge power difference in the large time interval.

The charging and discharging power difference (charging power minus discharging power) in a small period is calculated according to the normalized power of the battery cell to be monitored at each moment in the small period, and it can be understood that the battery cell to be monitored in the small period has a moment in a charging state and a moment in a discharging state. And calculating the change rate of the charge-discharge power difference of the battery cell to be monitored in the large time period according to the charge-discharge power difference of each small time period in the large time period. The charge-discharge power difference change rate of the battery cell to be monitored in a plurality of time periods can be calculated according to the requirement. The charging and discharging power difference change rate can reflect the condition that the internal damage of the battery cell to be monitored is increased, and if the charging and discharging power difference change rate is increased, the internal damage of the battery cell to be monitored is increased, and the abnormal condition possibly occurring inside is shown. Therefore, the safety state of the battery cell to be monitored is judged by combining the charging and discharging power difference, and the accuracy of safety monitoring can be improved.

Further, in an embodiment, the acquisition, analysis, calculation and processing of the monitoring parameter information may be implemented by a centralized control board in an energy storage system (or called a container), and the system architecture of the centralized control board integrates the information acquisition, the information analysis, calculation and system control into one centralized control board for processing. In another embodiment, as shown in fig. 4, the processing may be performed on the basis of a plurality of distributed independent control panels, and the processing results of the independent control panels may be collectively analyzed to perform system control. In another embodiment, as shown in fig. 5 and fig. 6, the information in the energy storage system may also be collected and sent to a remote cloud server for analysis and computation (the computing power of the cloud server is strong), and the result is sent to each energy storage system for control after the analysis and processing.

In addition, an embodiment of the present invention further provides an energy storage system safety monitoring device, and referring to fig. 7, the energy storage system safety monitoring device includes:

the acquisition module 10 is configured to acquire monitoring parameter information obtained by monitoring each battery cell to be monitored during an operation process of the energy storage system;

the comparison module 20 is configured to, for each of the electric cells to be monitored, divide the electric cells into the same group according to a preset grouping rule, compare the monitoring parameter information of each of the electric cells in the same group to obtain a parameter comparison result;

the determining module 30 is configured to determine a safety monitoring result of the to-be-monitored electric core according to the parameter comparison result obtained by comparing the to-be-monitored electric core in at least one group.

Further, the monitoring parameter information includes at least one monitoring parameter value of the battery core to be monitored, and any one target is grouped, and the comparison module 20 is further configured to:

for any target electric core in the target grouping, comparing any item target parameter value of the to-be-compared parameter values of the target electric core with the corresponding normal parameter range to obtain a range comparison result corresponding to the target parameter value, where the range comparison result includes a result representing whether the target parameter value exceeds the corresponding normal parameter range and/or a result representing an exceeding degree of the target parameter value exceeding the corresponding normal parameter range;

Further, when each of the to-be-compared parameter values of the target cell includes an electrical parameter value and a temperature parameter value, the determining module 30 is further configured to:

if the electrical abnormity grade is larger than a first preset grade, determining a grouping abnormity grade of the target electric core according to the electrical abnormity grade and the temperature abnormity grade of the target electric core, wherein the temperature abnormity grade is determined according to the range comparison result corresponding to the temperature parameter value of the target electric core;

Further, before the operation of comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result, the apparatus further includes:

the grouping module is used for dividing the electric cores in the same electric core string in the electric cores to be monitored into the same group; and/or the cells which are in the same working condition at the same time or the same time period in the cells to be monitored are divided into the same group, wherein the same working condition is the condition that one or more working condition parameters in a fan gear, a charge-discharge state, electric quantity and current magnitude are the same.

the comparison module 20 is further configured to:

comparing the time parameter values of each first electric core in a first group to obtain a first parameter comparison result, wherein the first group is a group consisting of the electric cores which are in the same working condition at the safety analysis time in each electric core to be monitored;

Further, the obtaining module 10 is further configured to:

the obtaining module 10 is further configured to:

Further, the determining module 10 is further configured to:

Further, after the device, the method further comprises:

and the execution module is used for executing an exception handling measure corresponding to the safety monitoring result of the electric core to be monitored when the safety monitoring result representation of the electric core to be monitored needs to carry out exception handling on the electric core to be monitored, wherein the exception handling measure comprises outputting an early warning prompt and/or cutting off connection.

The expansion content of the specific embodiment of the energy storage system safety monitoring device of the invention is basically the same as that of each embodiment of the energy storage system safety monitoring method, and is not described herein again.

In addition, an embodiment of the present invention further provides a computer-readable storage medium, where the storage medium stores an energy storage system safety monitoring program, and the energy storage system safety monitoring program, when executed by a processor, implements the following steps of the energy storage system safety monitoring method.

The embodiments of the energy storage system safety monitoring device and the computer-readable storage medium of the present invention can refer to the embodiments of the energy storage system safety monitoring method of the present invention, and are not described herein again.

It should be noted that, in this document, the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrases "comprising a component of' 8230; \8230;" does not exclude the presence of another like element in a process, method, article, or apparatus that comprises the element.

The above-mentioned serial numbers of the embodiments of the present invention are merely for description and do not represent the merits of the embodiments.

Through the description of the foregoing embodiments, it is clear to those skilled in the art that the method of the foregoing embodiments may be implemented by software plus a necessary general hardware platform, and certainly may also be implemented by hardware, but the former is a better implementation in many cases. Based on such understanding, the technical solutions of the present invention or portions thereof contributing to the prior art may be embodied in the form of a software product, which is stored in a storage medium (such as ROM/RAM, magnetic disk, optical disk) and includes instructions for enabling a terminal device (such as a mobile phone, a computer, a server, an air conditioner, or a network device) to execute the method according to the embodiments of the present invention.

The above description is only for the preferred embodiment of the present invention and is not intended to limit the scope of the present invention, and all modifications of equivalent structures and equivalent processes, which are made by the contents of the present specification and the accompanying drawings, or directly or indirectly applied to other related arts, are included in the scope of the present invention.

Claims

1. The energy storage system safety monitoring method is characterized by comprising the following steps of:

2. The energy storage system safety monitoring method according to claim 1, wherein the monitoring parameter information includes at least one monitoring parameter value of the battery cell to be monitored, any one object group is grouped, and the step of comparing the monitoring parameter information of each battery cell in the object group to obtain the parameter comparison result includes:

3. The energy storage system safety monitoring method according to claim 2, wherein when the parameter values to be compared of the target battery cell include an electrical parameter value and a temperature parameter value, the step of determining the grouping abnormality level of the target battery cell according to the range comparison result corresponding to the parameter values to be compared of the target battery cell includes:

4. The energy storage system safety monitoring method according to claim 1, wherein before the step of comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result, the method further comprises:

5. The safety monitoring method for the energy storage system according to claim 1, wherein the monitoring parameter information includes at least one time parameter value obtained by monitoring the electrical core to be monitored at a safety analysis time, and at least one parameter change rate obtained by monitoring at least one historical period before the safety analysis time;

the step of comparing the monitoring parameter information of each battery cell in the same group to obtain a parameter comparison result includes:

comparing the time parameter values of the battery cells in a second grouping to obtain a second parameter comparison result, wherein the second grouping is a grouping formed by the battery cells to be monitored in the battery cell string in which the first abnormal battery cell is located, and the first abnormal battery cell is a battery cell in which the grouping abnormal grade represented by the first parameter comparison result in each first battery cell is greater than a second preset grade;

6. The energy storage system safety monitoring method according to claim 1, wherein the step of acquiring monitoring parameter information obtained by respectively monitoring each battery cell to be monitored in the operation process of the energy storage system comprises:

7. The energy storage system safety monitoring method according to claim 6, wherein the time-normalized parameter values include at least time-normalized electrical values, and the time-normalized electrical values include at least time-normalized voltage values and time-normalized current values;

calculating to obtain a time normalization power value of the battery cell to be monitored according to the time normalization voltage value and the time normalization current value of the battery cell to be monitored at the same time;

calculating to obtain the voltage change rate of the electric core to be monitored in the corresponding time period according to the time normalization voltage values of the electric core to be monitored in each time period;

8. The energy storage system safety monitoring method according to claim 1, wherein the step of determining the safety monitoring result of the to-be-monitored battery cell according to the parameter comparison result obtained by comparing the to-be-monitored battery cell in at least one group includes:

9. The energy storage system safety monitoring method according to any one of claims 1 to 8, wherein after the step of determining the safety monitoring result of the cell to be monitored according to the parameter comparison result obtained by comparing the cell to be monitored in at least one group, the method further includes:

10. An energy storage system safety monitoring device, characterized in that, energy storage system safety monitoring device includes:

11. An energy storage system safety monitoring device, comprising: a memory, a processor and an energy storage system safety monitoring program stored on the memory and executable on the processor, the energy storage system safety monitoring program when executed by the processor implementing the steps of the energy storage system safety monitoring method as claimed in any one of claims 1 to 9.

12. A computer-readable storage medium, characterized in that the computer-readable storage medium has stored thereon an energy storage system safety monitoring program, which when executed by a processor implements the steps of the energy storage system safety monitoring method according to any one of claims 1 to 9.