WO2023044872A1

WO2023044872A1 - Method and apparatus for determining displayed state of charge (soc) of battery pack

Info

Publication number: WO2023044872A1
Application number: PCT/CN2021/120791
Authority: WO
Inventors: 黄磊; 陈晨; 徐广玉; 赵微
Original assignee: 宁德时代新能源科技股份有限公司
Priority date: 2021-09-26
Filing date: 2021-09-26
Publication date: 2023-03-30
Also published as: CN116670524A

Abstract

The present application relates to the field of battery management, and provides a method and apparatus for determining a displayed state of charge (SOC) of a battery pack. The method comprises: obtaining an actual SOC of the m-th sampling period corresponding to a current moment k and a displayed SOC of the n-th display period corresponding to the current moment k, the current moment k being a moment before the end of the n-th display period; determining a rate of change of a displayed SOC of the (n+1)-th display period according to a charging/discharging state of a battery pack at the current moment k, the displayed SOC of the n-th display period, the actual SOC of the m-th sampling period, and a rate of change of the displayed SOC of the n-th display period; and determining the displayed SOC of the (n+1)-th display period according to the rate of change of the displayed SOC of the (n+1)-th display period and the displayed SOC of the n-th display period. In this way, correction of the displayed SOC is realized, so that the SOC displayed at the (n+1)-th moment is more accurate.

Description

Method and device for determining the display state of charge SOC of a battery pack

technical field

The present application relates to the field of battery management, in particular, to a method and device for determining the SOC of a battery pack.

Background technique

When an electronic device powered by a battery is in use, usually, the display interface of the electronic device will display the SOC of the battery's state of charge (SOC). Displaying the SOC can be used to indicate the current remaining power of the battery, so that the user can charge or discharge the battery.

However, there is often a deviation between the displayed SOC and the actual SOC, and how the displayed SOC can accurately reflect the actual SOC has become an urgent technical problem in the field of battery management.

Contents of the invention

The purpose of the present application is to provide a method and device for determining the SOC of a battery pack, so as to improve the accuracy of the SOC display.

In a first aspect, the present application provides a method for determining the SOC of a battery pack, including:

Acquire the actual SOC of the mth sampling period corresponding to the current moment k and the display SOC of the nth display period corresponding to the current moment k, where the current moment k is the moment before the end of the nth display period;

According to the charging and discharging state of the battery pack at the current moment k, the displayed SOC of the nth display period, the actual SOC of the mth sampling period, and the change rate of the displayed SOC of the nth display period , to determine the rate of change of the display SOC of the n+1th display period;

According to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, determine the display SOC of the n+1th display period, and the n is an integer greater than or equal to 1 , the m is an integer greater than or equal to 1, and the k is an integer greater than or equal to 1.

In the above method, when the displayed SOC at the nth moment deviates from the actual SOC at the nth moment, the rate of change of the displayed SOC at the n+1 time may be determined according to the charging and discharging state at the nth moment. Furthermore, the display SOC at the (n+1)th time is calculated according to the display SOC at the nth time and the determined rate of change. In this way, the display SOC is corrected, and the display SOC viewed by the user at the n+1th moment is more accurate.

In one possible implementation,

According to the charging and discharging state of the battery pack at the current time k, the displayed SOC of the nth display period, the actual SOC of the mth sampling period, and the displayed SOC of the nth display period Change rate, to determine the change rate of the display SOC of the n+1th display cycle, including:

In the case that the battery pack is in the charging state at the current time k and has not reached the charging end, according to the displayed SOC of the nth display period, the actual SOC of the mth sampling period and the nth The rate of change of the display SOC of the first display period is determined to determine the rate of change of the display SOC of the n+1th display period.

In one possible implementation,

Determine the change rate of the display SOC of the n+1th display period according to the following formula:

ChangeRate(n+1)=KC*ChangeRate(n)*[1-(DSOC(n)-ASOC(m))/(FSOC-DSOC(n))];

Among them, ChangeRate(n+1) is the change rate of the display SOC in the n+1th display cycle;

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display period at the current moment k;

ASOC(m) is the actual SOC of the mth sampling period at the current moment k;

FSOC is the corresponding display SOC set when the battery pack is fully charged, and the FSOC is greater than DSOC(n);

KC is a preset first adaptive adjustment parameter, where KC∈(0,1).

In one possible implementation,

In the case that the battery pack is in the discharge state at the current moment k, the rate of change of the display SOC of the n+1th display cycle is determined according to the following formula:

ChangeRate(n+1)=KD*ChangeRate(n)*[1+(DSOC(n)-ASOC(m))/DSOC(n)];

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display period at the current moment k, and is not 0;

The actual SOC (m) is the actual SOC of the mth sampling period at the current moment k;

KD is the preset second adaptive adjustment parameter, where KD∈(0,1)

In a possible implementation manner, the display SOC of the n+1th display period is determined according to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, include:

According to the formula DSOC(n+1)=DSOC(n)+StepSOC(n+1)*Cd*ChangeRate(n+1), calculate the display SOC at the n+1th moment;

Among them, DSOC(n+1) is the display SOC of the n+1th display cycle;

DSOC(n) is the display SOC of the nth display cycle;

StepSOC(n+1) is the actual SOC change in the n+1th display cycle;

Cd is a value representing the direction of the current. When the battery pack is in a charging state, the Cd is +1, and when the battery pack is in a discharging state, the Cd is -1.

In a possible implementation manner, the change amount of the actual SOC in the n+1th display period is determined in the following manner:

StepSOC(n+1)=Td*I(k)/Ncap;

Wherein, Td is the duration of a display cycle;

I(k) is the current value of the battery pack at the current moment k;

Ncap is the nominal capacity of the battery pack.

In the second aspect, the present application also provides a device for determining the display state of charge SOC of the battery pack, including:

An acquisition module, configured to acquire the actual SOC of the mth sampling period corresponding to the current moment k and the display SOC of the nth display period corresponding to the current moment k, where the current moment k is the end of the nth display period the moment before

A determining module, configured to, according to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual SOC of the mth sampling cycle, and the display SOC of the nth display cycle Display the change rate of SOC, and determine the change rate of display SOC in the n+1th display cycle;

A calculation module, configured to determine the display SOC of the n+1th display period according to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, where n is greater than or an integer equal to 1, the m is an integer greater than or equal to 1, and the k is an integer greater than or equal to 1.

In a third aspect, the present application also provides a battery management chip, including: a processor and a memory, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the operation The method as described in the first aspect of the present application.

In a fourth aspect, an embodiment of the present application provides an electronic device, including a processor and a memory, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the operation is as described above The steps in the method provided in the first aspect.

In a fifth aspect, the embodiment of the present application provides a readable storage medium on which a computer program is stored, and when the computer program is executed by a processor, the steps in the method provided in the first aspect above are performed.

Other features and advantages of the present application will be set forth in the ensuing description and, in part, will be apparent from the description, or can be learned by practicing the embodiments of the present application. The objectives and other advantages of the application may be realized and attained by the structure particularly pointed out in the written description and claims hereof as well as the appended drawings.

Description of drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the accompanying drawings that need to be used in the embodiments of the present application will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present application, so It should not be regarded as a limitation on the scope, and those skilled in the art can also obtain other related drawings according to these drawings without creative work.

FIG. 1 is a flow chart 1 of a method for determining the display SOC of a battery pack provided in an embodiment of the present application;

FIG. 2 is a schematic diagram of two cycles of the SOC of the battery pack of the battery pack provided by the embodiment of the present application;

FIG. 3 is the second flow chart of the method for determining the display SOC of the battery pack provided by the embodiment of the present application;

FIG. 4 is a block diagram of the functional modules of the display SOC device of the battery pack provided by the embodiment of the present application;

FIG. 5 is a circuit connection block diagram of an electronic device provided by an embodiment of the present application.

Detailed ways

Explanation of technical terms:

SOC: State of charge SOC (state of charge, SOC), the ratio of the remaining capacity of the battery to the capacity of the fully charged state after it has been used for a period of time or left unused for a long time.

Display SOC: The state of charge of the battery pack displayed on the display screen of the electronic device.

Actual SOC: The true state of charge of the battery pack of the electronic device.

Terminal voltage: refers to the voltage value at both ends of the cell collected by the power management system.

The technical solutions in the embodiments of the present application will be clearly and completely described below in conjunction with the drawings of the embodiments of the present application.

At present, the method of correcting and displaying SOC is as follows: obtain multiple battery operating parameters (such as current, temperature, terminal voltage, etc.) of the battery, and input multiple battery operating parameters into the preset open-circuit voltage calculation model to calculate the open-circuit voltage of the battery. According to the open circuit voltage value, it is judged whether the display SOC needs to be calibrated; if so, according to the preset calibration table, it is determined that the battery is at the open circuit voltage value and the display

Target calibration factor under SOC; calibrates the displayed SOC according to the target calibration factor. However, the open circuit voltage value calculated according to the open circuit voltage calculation model, for LFP cells, is limited by its model error and cell characteristics, the calculated real SOC is not accurate enough, resulting in inaccurate displayed SOC after calibration, and a display will appear Uneven SOC calculation speed and jumps affect the user experience.

The present application provides a method for determining the display state of charge SOC of a battery pack, which is applied to an electronic device that needs to display the state of charge to a user. Specifically, a battery management system (Battery Management System, BMS for short) may be provided in the electronic device, and the method for determining the displayed SOC of the battery pack provided in this application may be specifically applied to the BMS. Wherein, the electronic device may be, but not limited to, an electronic device powered by a battery pack, such as a smart phone, a tablet computer, and an electric vehicle.

As shown in FIG. 1 , the method for determining the SOC of a battery pack provided in the embodiment of the present application may include the following steps.

S21: Obtain the actual SOC of the mth sampling period corresponding to the current time k and the display SOC of the nth display period corresponding to the current time k.

The current time k is the time before the end of the nth display period. Exemplarily, the current moment k may be any moment within the nth display period and after a specified ratio of the nth display period. For example, the current time k may be any time after four-fifths of the cycle in the nth display cycle. For example, the current time k may be at the nine-tenths cycle time of the nth display cycle. For another example, the current time k may be at the time of fourteen-fifteenths of the nth display period.

The current moment may be at a critical moment between two adjacent sampling periods, or within any sampling period.

The power management system usually records the relevant parameters of the battery pack, such as charging and discharging status, actual SOC, and displayed SOC, in each acquisition time period within a fixed time period. Optionally, but the time length of each parameter collection period may be the same or different (in the example shown in FIG. 2 , the display period for displaying the SOC is different from the sampling period for the actual SOC).

As a possible implementation manner, the battery management system acquires and records the actual SOC in each sampling period in the sampling period; acquires and records the displayed SOC in each display period in the display period.

According to specific requirements, the above-mentioned sampling period may be a fixed value during the effective use of the battery pack, and the above-mentioned display period may be a definite value during the effective use of the battery pack. At present, if there are other requirements, the above-mentioned sampling period can also adopt different values in different life stages of the battery pack, and the above-mentioned display period can also adopt different values in different life stages of the battery pack.

As shown in FIG. 2 , the illustration shows two cycle schematic diagrams of the battery pack, which are the display cycle and the sampling cycle respectively. Among them, a plurality of display periods are shown on the display period: Td1, Td2, Td3, ..., Td(n), Td(n+1), ..., and the display SOC corresponding to each display period, for example, the first The display SOC corresponding to the display period Td1 is DSOC(1), and the display SOC corresponding to the nth display period Td(n) is DSOC(n). Multiple sampling periods are shown on the sampling period: Ts1, Ts2, Ts3, ..., Ts(m), ..., and the actual SOC corresponding to each sampling period, for example, the actual SOC corresponding to the first sampling period Ts1 is ASOC (1) The actual SOC corresponding to the mth display period Td(m) is ASOC(m).

In the example shown in FIG. 2 , the current moment k is a critical moment between the nth display period T(n) and the nth display period T(n+1), and the current moment k is within the mth sampling period.

In order to facilitate the recording of different times and the sampling period and display period corresponding to the time, the time is recorded as: the 0th moment, the 1st moment, the 2nd moment, the 3rd moment..., the k-1th moment, the kth moment, the th At k+1 moment.....; record the sampling period as: the 1st sampling period, the 2nd sampling period, the 3rd sampling period, ..., the m-1th sampling period, the mth sampling period, the th m+1 sampling period.....; record the display period as: 1st display period, 2nd display period, 3rd display period, ..., n-1th display period, nth display period , the n+1th display cycle..... Wherein, k, n, and m are all integers greater than or equal to 1.

As a possible implementation manner, the electronic device may acquire the display SOC in the following manner: the electronic device records the display SOC in a memory before each power-off. At the initial moment when the electronic device is powered on, the display SOC recorded before the last power-off of the memory can be read as the display SOC of the first display cycle.

As a possible implementation, the electronic device can obtain the actual SOC in the following way: collect parameters such as the current temperature, current, working condition, and available power range of the cells in the battery pack, and in each sampling cycle, according to the battery The actual SOC in each sampling period is calculated according to the actual SOC calculation method such as the ampere-hour integral method and other parameters such as temperature, current, working condition, and usable power range of the cells in the package during the sampling period.

As a possible implementation manner, as shown in FIG. 2 , the battery management system can determine the m-th sampling period and the n-th display period corresponding to the current time k according to the current time k. Based on the time of the current time k, the actual SOC of the mth sampling period and the display SOC of the nth display period corresponding to the current time k can be determined.

As a possible implementation manner, the current time k is a time before the end of the nth display period, then the next time k+1 of the current time k may be the time when the n+1th display period starts.

S22: According to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual SOC of the mth sampling cycle, and the change rate of the display SOC of the nth display cycle, determine the n+1th display cycle The rate of change of the display SOC for each display period.

Wherein, the charge and discharge state includes a charge state and a discharge state, wherein the charge state includes a direct charge state and a recharge state.

As a possible implementation, when it is detected that the charging interface of the electronic device is plugged with a charging device (such as a charging gun, a power bank, etc.) and the direction of the current is the input direction, it is obtained that the battery pack is in the state of direct charging; another On the one hand, when it is not detected that the charging interface of the electronic device is plugged with a charging device (such as a charging gun, charging treasure, etc.) and the current direction is the input direction, it is obtained that the battery pack is in the recharging state; on the other hand, when it is detected When the current direction of the electronic device is the output direction, it is obtained that the battery pack is in a discharging state.

Generally, there is a deviation between the displayed SOC at the same time and the actual SOC. Wherein, the deviation includes higher or lower. Understandably, if the display SOC of the nth display period corresponding to the current moment k is greater than the actual SOC of the mth sampling period, or exceeds the first preset range of the actual SOC of the mth sampling period, then the nth display period is determined The display SOC of the period is too high; if the actual SOC of the mth sampling period corresponding to the current moment k is greater than the display SOC of the nth display period, or exceeds the second preset range of the display SOC of the nth display period, then determine the The display SOC of n display periods is low.

As a possible implementation, S22 can specifically be: when the battery pack at the current moment k is in the charging state and has not reached the charging end, according to the change of the displayed SOC at the nth moment and the displayed SOC at the n+1th moment Rate, calculate the display SOC at the n+1th moment.

Based on the above, S22 may include the following four possible implementations:

The first solution: at the current moment k battery pack is in the charging state and has not reached the charging end, and the display SOC of the nth display cycle is too high, according to the change rate of the display SOC of the nth display cycle, determine The change rate of the display SOC in the n+1th display period, and the change rate of the display SOC in the n+1th display period is smaller than the change rate of the display SOC in the nth display period.

In this embodiment, when the k battery pack is in the charging state at the current moment and has not reached the charging end, and the display SOC of the nth display cycle is too high, it is necessary to reduce the change of the display SOC in the n+1th display cycle rate, so that the display SOC of the n+1th display cycle is closer to the actual SOC.

The second solution: at the current moment k battery pack is in the charging state and has not reached the charging end, and the display SOC of the nth display cycle is low, according to the change rate of the display SOC of the nth display cycle, determine The change rate of the display SOC in the n+1th display period, and the change rate of the display SOC in the n+1th display period is greater than the change rate of the display SOC in the nth display period.

In this embodiment, when the k battery pack is in the charging state at the current moment and has not reached the charging end, and the display SOC of the nth display cycle is low, it is necessary to increase the change of the display SOC in the n+1 display cycle rate, so that the displayed SOC at the n+1th moment is closer to the actual SOC.

In this embodiment, in the above-mentioned first scheme and the second scheme, it may be determined that the battery pack is in an end-of-charging state when any of the following conditions is detected to be satisfied. The conditions include but are not limited to: the current value of the charging current is less than a preset current value, the voltage value of the cell terminal voltage of the battery pack is greater than a preset voltage value, or the displayed SOC is greater than a preset SOC value. Otherwise, it is determined that the battery pack is not in an end-of-charging state.

It should be noted that, when the end of charging is not reached, using the change rate of the display SOC of the n+1th display cycle to calculate the display SOC of the n+1th display cycle can take into account the accuracy of the display SOC and the No transitions will occur.

The third solution: when the k battery pack is in the discharge state at the current moment, and the display SOC of the nth display cycle is too high, according to the change rate of the display SOC of the nth display cycle, determine the n+1th display The rate of change of the display SOC of the period, and the rate of change of the display SOC of the n+1th display period is greater than the rate of change of the display SOC of the nth display period.

In this embodiment, when the k battery pack is in the discharge state at the current moment, and the display SOC of the nth display cycle is relatively high, it is necessary to increase the change rate of the display SOC in the n+1 display cycle, so that the nth display cycle The displayed SOC at +1 moment is closer to the actual SOC.

The fourth solution: when the k battery pack is in the discharge state at the current moment, and the display SOC of the nth display cycle is low, according to the change rate of the display SOC of the nth display cycle, determine the n+1th display The rate of change of the display SOC of the period, and the rate of change of the display SOC of the n+1th display period is smaller than the rate of change of the display SOC of the nth display period.

In this embodiment, when the k battery pack is in the discharge state at the current moment, and the display SOC of the nth display cycle is low, it is necessary to reduce the change rate of the display SOC in the n+1 display cycle, so that the nth display cycle The displayed SOC of +1 display cycle is closer to the actual SOC.

S23: Determine the display SOC of the n+1th display period according to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period.

It can be understood that the display SOC of the n+1th display period depends at least on the magnitude of the display SOC of the nth display period and the change rate of the display SOC of the n+1th display period. This iterative calculation method makes the display SOC of the next display cycle have higher accuracy.

As a possible implementation manner, the scheme for determining the display SOC of the n+1th display period includes but is not limited to the following two:

Solution 1: If the battery pack is in the discharge state, then determine the change rate of the displayed SOC in the n+1th display cycle according to the following formula:

ChangeRate(n+1)=KD*ChangeRate(n)*[1+(DSOC(n)-ASOC(n))/(DSOC(n))].

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display cycle at the current moment k;

ASOC(n) is the actual SOC of the mth sampling period at the current moment k;

KD is a preset second adaptive adjustment parameter, where KD∈(0,1).

Understandably, when the battery pack is in a discharging state, (DSOC(n)-ASOC(n))/DSOC(n) is the deviation rate of the displayed SOC. When the difference between DSOC(n) and ASOC(n) is greater than 0, it indicates that the SOC is high and the rate of change of SOC is low, and [1+(DSOC(n)-ASOC(n))/DSOC(n )] is greater than 1, then ChangeRate(n+1) can be made greater than ChangeRate(n). When DSOC(n)-ASOC(n) is less than 0, it indicates that the SOC is low and the rate of change of SOC is high, and [1+(DSOC(n)-ASOC(n))/DSOC(n)] is less than 1, then ChangeRate(n+1) can be made smaller than ChangeRate(n).

Solution 2: If the battery pack is in the charging state and has not reached the charging end state, then according to the following formula, determine the change rate of the displayed SOC in the n+1th display cycle:

ChangeRate(n+1)=KC*ChangeRate(n)*[1-(DSOC(n)-ASOC(n))/(FSOC-DSOC(n))],

in,

ChangeRate(n+1) is the change rate of display SOC in the n+1th display cycle;

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display cycle at the current moment k;

ASOC(n) is the actual SOC of the mth sampling period at the current moment k;

FSOC is the corresponding display SOC when the set battery pack is fully charged;

KC is a preset first adaptive adjustment parameter, where KC∈(0,1).

Exemplarily, (DSOC(n)-ASOC(n))/(FSOC-DSOC(n)) is the deviation rate of the displayed SOC when the battery pack is in the charging state and has not reached the charging end state. Since the end of charge has not been reached, FSOC is greater than DSOC(n). When DSOC(n)-ASOC(n) is greater than 0, it indicates that the SOC is high, and [1-(DSOC(n)-ASOC(n))/(FSOC- DSOC(n))] is less than 1, then it can be Make ChangeRate(n+1) smaller than ChangeRate(n). When DSOC(n)-ASOC(n) is less than 0, it means that the SOC is low, and [1-(DSOC(n)-ASOC(n))/(FSOC-DSOC(n))] is greater than 1, then it can be Make ChangeRate(n+1) greater than ChangeRate(n).

As a possible implementation manner, the calculation of the display SOC of the n+1th display period may be performed in the following manner:

As shown in Figure 3, the method for determining and calculating the display SOC of the n+1th display cycle includes:

S31: Determine whether the battery pack is in a charging state and has not reached the charging end state.

If yes, execute S32.

S32: Calculate the display SOC of the n+1th display cycle according to the following formula:

DSOC(n+1)=DSOC(n)+StepSOC(n+1)*Cd*ChangeRate(n+1);

Among them, DSOC(n+1) is the SOC displayed at the n+1th moment;

Display SOC(n) is to display SOC at the nth moment;

StepSOC(n+1) is the actual SOC change in the n+1th display cycle;

Wherein, the variation of the actual SOC within one display cycle can be calculated by the ampere-hour integration method and the actual current flowing through the battery pack. Exemplarily, the variation of the actual SOC in the above n+1th display period may be determined in the following manner:

StepSOC(n+1)=Td*I(k)/Ncap;

Wherein, Td is the duration of a display cycle;

I(k) is the current value of the battery pack at the current time k, and the current value I(k) of the battery pack is the current value of the main circuit at the current time k during the charging and discharging process of the battery pack.

Ncap is the nominal capacity of the battery pack. In this embodiment, the nominal capacity Ncap of the battery pack is a preset value, which can be determined according to the currently calculated battery pack.

In this embodiment, the display SOC at the n+1th moment in the first scheme is calculated according to the change rate ChangeRate(n+1) of the display SOC at the n+1th moment, and the display at the n+1th moment The SOC change rate ChangeRate(n+1) is calculated based on the actual SOC.

Please refer to FIG. 3 , the present application also provides a device 40 for determining the SOC of a battery pack, which is applied to an electronic device powered by a battery pack when it is in a working state. Specifically, the electronic device includes a battery management system (Battery Management System, BMS for short), and the above method for determining the display SOC of the battery pack can be specifically applied to the BMS. It should be noted that the basic principles and technical effects of the device 40 for determining the SOC of the battery pack provided by the embodiment of the present application are the same as those of the above-mentioned embodiments. For the sake of brief description, this embodiment does not mention For details, reference may be made to the corresponding content in the above-mentioned embodiments. The device 40 includes an acquisition module 41, a determination module 42, and a calculation module 43, wherein,

An acquisition module 41, configured to acquire the actual SOC of the mth sampling period corresponding to the current moment k and the display SOC of the nth display period corresponding to the current moment k, where the current moment k is the nth display period the moment before the end;

A determining module 42, configured to, according to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual SOC of the mth sampling cycle, and the nth display cycle The rate of change of the displayed SOC is determined to determine the rate of change of the displayed SOC of the n+1th display cycle;

A calculation module 43, configured to determine the display SOC of the n+1th display period according to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, where n is An integer greater than or equal to 1, the m is an integer greater than or equal to 1, and the k is an integer greater than or equal to 1.

In a possible design solution, the determining module 42 can be specifically configured to, in the case that the battery pack is in the charging state at the current moment k and has not reached the end of charging, according to the displayed SOC of the nth display cycle, the The actual SOC of the mth sampling period and the change rate of the display SOC of the nth display period are determined to determine the change rate of the display SOC of the n+1th display period.

In a possible design solution, the change rate of the display SOC of the n+1th display period is determined according to the following formula:

ChangeRate(n+1)=KC*ChangeRate(n)*[1-(DSOC(n)-ASOC(m))/(FSOC-DSOC(n))];

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display period at the current moment k;

ASOC(m) is the actual SOC of the mth sampling period at the current moment k;

KC is a preset first adaptive adjustment parameter, where KC∈(0,1).

In a possible design solution, when the battery pack is in a discharge state at the current moment k, the rate of change of the display SOC of the n+1th display cycle is determined according to the following formula:

ChangeRate(n+1)=KD*ChangeRate(n)*[1+(DSOC(n)-ASOC(m))/DSOC(n)];

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

KD is a preset second adaptive adjustment parameter, where KD∈(0,1).

In a possible design scheme, the calculation module 43 can be specifically used for:

Among them, DSOC(n+1) is the display SOC of the n+1th display cycle;

DSOC(n) is the display SOC of the nth display cycle;

StepSOC(n+1) is the actual SOC change in the n+1th display cycle;

In a possible design solution, the actual SOC variation in the n+1th display period is determined in the following manner:

StepSOC(n+1)=Td*I(k)/Ncap;

Wherein, Td is the duration of a display cycle;

I(k) is the current value of the battery pack at the current moment k;

Ncap is the nominal capacity of the battery pack.

The defects in the solutions in the above prior art are all the results obtained by the inventor after practice and careful research. Therefore, the discovery process of the above problems and the solutions to the above problems proposed by the embodiments of the present invention below , should be the inventor's contribution to the invention during the process of the invention.

In addition, the present application also provides a battery management chip, including: a processor and a memory, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the operation is as described above in this application. The display SOC determination method of the battery pack in the embodiment.

Please refer to FIG. 4. FIG. 4 is a schematic structural diagram of an electronic device for performing a battery pack display SOC determination method provided by an embodiment of the present application. The electronic device may include: at least one processor 110, such as a CPU, at least one communication interface 120 , at least one memory 130 and at least one communication bus 140 . Wherein, the communication bus 140 is used to realize the direct connection and communication of these components. Wherein, the communication interface 120 of the device in the embodiment of the present application is used for signaling or data communication with other node devices. The memory 130 may be a high-speed RAM memory, or a non-volatile memory (non-volatile memory), such as at least one magnetic disk memory. Optionally, the memory 130 may also be at least one storage device located away from the aforementioned processor. Computer-readable instructions are stored in the memory 130 , and when the computer-readable instructions are executed by the processor 110 , the electronic device executes the above-mentioned method process shown in FIG. 2 .

It can be understood that the structure shown in FIG. 4 is only for illustration, and the electronic device may also include more or less components than those shown in FIG. 4 , or have a configuration different from that shown in FIG. 4 . Each component shown in FIG. 4 may be implemented by hardware, software or a combination thereof.

The means may be a module, program segment or code on the electronic device. It should be understood that the device corresponds to the above-mentioned embodiment of the method in FIG. 2 , and can perform various steps involved in the embodiment of the method in FIG. 2 . The specific functions of the device can refer to the description above. To avoid repetition, detailed descriptions are appropriately omitted here.

It should be noted that those skilled in the art can clearly understand that for the convenience and brevity of the description, the specific working process of the above-described system and device can refer to the corresponding process in the foregoing method embodiment, and the description will not be repeated here. .

An embodiment of the present application provides a readable storage medium on which a computer program is stored. When the computer program is executed by a processor, the method process performed by the electronic device in the method embodiment shown in FIG. 2 is executed.

This embodiment discloses a computer program product, the computer program product includes a computer program stored on a non-transitory computer-readable storage medium, the computer program includes program instructions, and when the program instructions are executed by the computer, the computer The methods provided by the above method embodiments can be executed, for example, including: acquiring the charging and discharging state of the battery pack at the nth moment, the displayed SOC at the nth moment, and the actual SOC at the nth moment; The deviation of the actual SOC; according to the deviation and the charge and discharge state at the nth moment, determine the change rate of the display SOC at the n+1 moment; according to the change rate of the display SOC at the n+1 moment and the display SOC at the nth moment, calculate The display SOC at the (n+1)th moment, where n is an integer greater than or equal to 1.

In the embodiments provided in this application, it should be understood that the disclosed devices and methods may be implemented in other ways. The device embodiments described above are only illustrative. For example, the division of the units is only a logical function division. In actual implementation, there may be other division methods. For example, multiple units or components can be combined or May be integrated into another system, or some features may be ignored, or not implemented. In another point, the mutual coupling or direct coupling or communication connection shown or discussed may be through some communication interfaces, and the indirect coupling or communication connection of devices or units may be in electrical, mechanical or other forms.

In addition, a unit described as a separate component may or may not be physically separated, and a component displayed as a unit may or may not be a physical unit, that is, it may be located in one place, or may be distributed to multiple network units. Part or all of the units can be selected according to actual needs to achieve the purpose of the solution of this embodiment.

Furthermore, each functional module in each embodiment of the present application may be integrated to form an independent part, each module may exist independently, or two or more modules may be integrated to form an independent part.

In this document, relational terms such as first and second etc. are used only to distinguish one entity or operation from another without necessarily requiring or implying any such relationship between these entities or operations. Actual relationship or sequence.

The above descriptions are only examples of the present application, and are not intended to limit the scope of protection of the present application. For those skilled in the art, various modifications and changes may be made to the present application. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of this application shall be included within the protection scope of this application.

Claims

A method for determining the display state of charge SOC of a battery pack, characterized in that it comprises:

Acquire the actual SOC of the mth sampling period corresponding to the current moment k and the display SOC of the nth display period corresponding to the current moment k, where the current moment k is the moment before the end of the nth display period;

According to the charging and discharging state of the battery pack at the current moment k, the displayed SOC of the nth display period, the actual SOC of the mth sampling period, and the change rate of the displayed SOC of the nth display period , to determine the rate of change of the display SOC of the n+1th display period;

According to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, determine the display SOC of the n+1th display period, and the n is an integer greater than or equal to 1 , the m is an integer greater than or equal to 1, and the k is an integer greater than or equal to 1.
The method according to claim 1, characterized in that, according to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual The SOC and the change rate of the display SOC of the nth display period determine the change rate of the display SOC of the n+1th display period, including:

In the case that the battery pack is in the charging state at the current time k and has not reached the charging end, according to the displayed SOC of the nth display period, the actual SOC of the mth sampling period and the nth The rate of change of the display SOC of the first display period is determined to determine the rate of change of the display SOC of the n+1th display period.
The method according to claim 2, wherein the rate of change of the display SOC of the n+1th display period is determined according to the following formula:

ChangeRate(n+1)=KC*ChangeRate(n)*[1-(DSOC(n)-ASOC(m))/(FSOC-DSOC(n))];

Among them, ChangeRate(n+1) is the change rate of the display SOC in the n+1th display cycle;

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display period at the current moment k;

ASOC(m) is the actual SOC of the mth sampling period at the current moment k;

FSOC is the corresponding display SOC set when the battery pack is fully charged, and the FSOC is greater than DSOC(n);

KC is a preset first adaptive adjustment parameter, where KC∈(0,1).
The method according to claim 1, characterized in that, according to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual The SOC and the change rate of the display SOC of the nth display period determine the change rate of the display SOC of the n+1th display period, including:

In the case that the battery pack is in the discharge state at the current moment k, the rate of change of the display SOC of the n+1th display cycle is determined according to the following formula:

ChangeRate(n+1)=KD*ChangeRate(n)*[1+(DSOC(n)-ASOC(m))/DSOC(n)];

Among them, ChangeRate(n+1) is the change rate of the display SOC in the n+1th display cycle;

ChangeRate(n) is the change rate of the display SOC in the nth display cycle;

DSOC(n) is the display SOC of the nth display period at the current moment k, and is not 0;

The actual SOC (m) is the actual SOC of the mth sampling period at the current moment k;

KD is a preset second adaptive adjustment parameter, where KD∈(0,1).
The method according to claim 3 or 4, wherein the n+1th display cycle is determined according to the change rate of the display SOC of the n+1th display cycle and the display SOC of the nth display cycle The display SOC of a display cycle, including:

According to the formula DSOC(n+1)=DSOC(n)+StepSOC(n+1)*Cd*ChangeRate(n+1), calculate the display SOC at the n+1th moment;

Among them, DSOC(n+1) is the display SOC of the n+1th display cycle;

DSOC(n) is the display SOC of the nth display cycle;

StepSOC(n+1) is the actual SOC change in the n+1th display cycle;

Cd is a value representing the direction of the current. When the battery pack is in a charging state, the Cd is +1, and when the battery pack is in a discharging state, the Cd is -1.
The method according to claim 5, wherein the variation of the actual SOC in the n+1th display period is determined by the following method:

StepSOC(n+1)=Td*I(k)/Ncap;

Wherein, Td is the duration of a display cycle;

I(k) is the current value of the battery pack at the current moment k;

Ncap is the nominal capacity of the battery pack.
A device for determining the display state of charge SOC of a battery pack, characterized in that it includes:

An acquisition module, configured to acquire the actual SOC of the mth sampling period corresponding to the current moment k and the display SOC of the nth display period corresponding to the current moment k, where the current moment k is the end of the nth display period the moment before

A determining module, configured to, according to the charging and discharging state of the battery pack at the current moment k, the display SOC of the nth display cycle, the actual SOC of the mth sampling cycle, and the display SOC of the nth display cycle Display the change rate of SOC, and determine the change rate of display SOC in the n+1th display cycle;

A calculation module, configured to determine the display SOC of the n+1th display period according to the change rate of the display SOC of the n+1th display period and the display SOC of the nth display period, where n is greater than or an integer equal to 1, the m is an integer greater than or equal to 1, and the k is an integer greater than or equal to 1.
A battery management chip, characterized by comprising: a processor and a memory, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the operation as claimed in claim 1 - the method described in any one of 6.
An electronic device, characterized in that it includes a processor and a memory, the memory stores computer-readable instructions, and when the computer-readable instructions are executed by the processor, the operation according to any one of claims 1-6 is performed. a method as described.
A readable storage medium on which a computer program is stored, wherein the computer program executes the method according to any one of claims 1-6 when executed by a processor.