CN117590264A - Self-adaptive calculation method, equipment and medium for standing current of battery system - Google Patents

Abstract

The invention discloses a self-adaptive calculation method, equipment and medium for standing current of a battery system, wherein the method comprises the following steps: s1: judging whether the current system is in a static state or not, and if so, judging whether the minimum monomer voltage is within a specified voltage range or not; s2: judging whether the voltage is stable or not, and if so, calculating the minimum monomer voltage Vmin1; s3: calculating the minimum monomer voltage Vmin2 after the standing process is finished; s4: and obtaining the SOC of the battery pack under the standing condition and the SOC of the battery pack under the ending standing condition according to the minimum cell voltage Vmin1 and the minimum cell voltage Vmin2, and calculating the standing current according to the standing process time. According to the invention, the static current is not directly collected, and the actual static current is estimated through the capacity change before and after the static time, so that the SOC estimation precision in a static state is improved.

Description

A battery system static current adaptive calculation method, equipment and medium

Technical field

The present invention relates to the field of power electronics technology, and more specifically to a battery system static current adaptive calculation method, equipment and medium.

Background technique

Since the resting current is very small, it is difficult to directly collect it through the battery system (BMS). The difference in the resting current will affect the estimation of the battery SOC. At the same time, the inaccuracy of the resting current leads to a large SOC estimation error.

Therefore, how to provide a method that can realize adaptive calculation of the standing current without directly collecting the standing current is an urgent problem that those skilled in the art need to solve.

Contents of the invention

In view of this, the present invention provides a battery system static current adaptive calculation method, equipment and medium to estimate the current size of the BMS system when it is in a static state, and reduce the inaccurate estimation of battery SOC caused by inaccurate static current collection. problem, thereby improving the estimation accuracy of SOC in the static state.

In order to achieve the above objects, the present invention adopts the following technical solutions:

In a first aspect, the present invention provides an adaptive calculation method for battery system resting current, including:

S1: Determine whether the current system is in a static state, and if so, determine whether the minimum cell voltage Vmin0 is within the specified voltage range;

S2: Determine whether the voltage is stable, and if stable, calculate the minimum cell voltage Vmin1;

S3: Calculate the minimum cell voltage Vmin2 after the resting process;

S4: According to the minimum cell voltage Vmin1 and the minimum cell voltage Vmin2, obtain the SOC when the battery pack enters the static condition and the SOC when the battery pack ends the static condition, and calculate the static current according to the duration of the static process.

Preferably, the specific implementation process of S1 is:

Determine whether the sampling current is equal to 0. If the current is equal to 0 at this time, it means that the current system is in a static state;

Determine whether the minimum cell voltage Vmin0 is within the range of 3350mv~3550mv or 2800mv~3280mv. If satisfied, proceed to the next step.

Preferably, in S3, the judgment principle for the end of the resting process is:

If there is charging and discharging current, the balancing mode is started, and when it enters the undervoltage state, the resting process is considered to be over.

Preferably, the calculation formula of the standing current in S4 is:

Pstandby＝(SOCstrat-SOCend)*Cap/T

Among them, Pstandby represents the static current, SOCstart represents the SOC of the battery pack when it enters the static condition, SOCend represents the SOC of the battery pack when it ends the static condition, Cap represents the total capacity of the battery pack, and T represents the duration of this static state.

Preferably, before calculating the resting current, it also includes:

Determine whether the duration of the resting process is greater than the preset value. If it is greater, determine whether the SOC under resting conditions is greater than the SOC under resting conditions at the end of the battery pack;

If it satisfies the calculation of the standing current;

Determine whether the standing current meets the preset conditions. If so, the calculated standing current is valid.

Preferably, the preset value is set to 24h; the preset condition is that the standing current is less than 500mA.

In a second aspect, the present invention provides a computer device, including:

Memory, used to store computer programs;

A processor, configured to implement the steps of the battery system resting current adaptive calculation method when executing the computer program.

In a third aspect, the present invention provides a computer-readable storage medium. A computer program is stored on the computer-readable storage medium. When the computer program is executed by a processor, the battery system static current adaptation is implemented. Steps of the calculation method.

It can be seen from the above technical solutions that compared with the existing technology, the present invention provides a battery system static current adaptive calculation method, equipment and medium, which can not directly collect the static current, but can calculate the static current through the capacity before and after the static time. Changes estimate the actual resting current, thereby improving the SOC estimation accuracy in the resting state.

Description of drawings

In order to explain the embodiments of the present invention or the technical solutions in the prior art more clearly, the drawings needed to be used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings in the following description are only These are embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on the provided drawings without exerting creative efforts.

Figure 1 is a flow chart of an adaptive calculation method for battery system resting current provided by the present invention.

Figure 2 is a method flow chart according to another embodiment of the present invention.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some of the embodiments of the present invention, rather than all the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts fall within the scope of protection of the present invention.

An embodiment of the present invention discloses an adaptive calculation method for battery system resting current, as shown in Figure 1, including:

S1: Determine whether the current system is in a static state. If satisfied, determine whether the minimum cell voltage Vmin0 is within the specified voltage range. The minimum cell voltage refers to the voltage of the battery string with the lowest voltage in the battery; specifically,

S101: Determine whether the sampling current is equal to 0. If the current is equal to 0 at this time, it means that the current system is in a static state; if not, the calculation ends;

S102: Determine whether the minimum cell voltage Vmin0 is within the range of 3350mv~3550mv or 2800mv~3280mv. If it is satisfied, proceed to the next step of judgment. If it is not satisfied, the calculation will end.

S2: Determine whether the voltage is stable. If it is stable, calculate the minimum cell voltage Vmin1. If it is not satisfied, judge whether the sampling current is 0. If it is not satisfied at the same time, end the calculation. If the sampling current is 0, continue to judge whether the voltage is stable;

S3: Calculate the minimum cell voltage Vmin2 after the resting process is over; specifically, determine whether the resting process is over. If there is charge and discharge current, or there is no charge and discharge current, but the balancing mode is started and the undervoltage state is entered, it is considered The resting process is completed.

S4: Use the SOC-OCV comparison table in Table 1 to obtain the SOC when the battery pack enters the static condition and the SOC when the battery pack ends the static condition based on the minimum cell voltage Vmin1 and the minimum cell voltage Vmin2, and calculate the static state based on the length of the static process. Set current:

Pstandby＝(SOCstrat-SOCend)*Cap/T

Among them, Pstandby represents the static current, SOCstart represents the SOC of the battery pack when it enters the static condition, SOCend represents the SOC of the battery pack when it ends the static condition, Cap represents the total capacity of the battery pack, and T represents the duration of this static state.

Table 1SOC-OCV comparison table

SOC[%] VcellMinimum[mV] 0 3202 10 3237 20 3267 30 3286 40 3289 50 3292 60 3322 70 3326 80 3328 90 3331 100 3405

Based on the above embodiments, embodiments of the present invention further provide an adaptive calculation method for battery system resting current, as shown in Figure 2, including:

S1: Determine whether the current system is in a static state, and if so, determine whether the minimum cell voltage Vmin0 is within the specified voltage range; specifically,

S101: Determine whether the sampling current is equal to 0. If the current is equal to 0 at this time, it means that the current system is in a static state. If not, the calculation ends;

S102: Determine whether the minimum cell voltage Vmin0 is within the range of 3350mv~3550mv or 2800mv~3280mv. If it is satisfied, proceed to the next step of judgment. If it is not satisfied, the calculation will end.

S2: Determine whether the voltage is stable. If it is stable, calculate the minimum cell voltage Vmin1. If it is not satisfied, judge whether the sampling current is 0. If it is not satisfied at the same time, end the calculation. If the sampling current is 0, continue to judge whether the voltage is stable;

S3: Calculate the minimum cell voltage Vmin2 after the resting process is over; specifically, determine whether the resting process is over. If there is charge and discharge current, or there is no charge and discharge current, but the balancing mode is started and the undervoltage state is entered, it is considered The resting process is completed. More specifically, the principle of judging whether the resting process is over is to judge whether the current at this time is 0. If it is not satisfied, the resting process will end. If it is satisfied, it will be further judged whether the termination monitoring voltage is reached. If it is reached, the resting process will end. If it is not reached, time accumulation is performed to determine whether the current is 0 again.

S4: Obtain the SOC when the battery pack enters the static condition and the SOC when the battery pack ends the static condition according to the minimum cell voltage Vmin1 and the minimum cell voltage Vmin2 through the SOC-OCV comparison table. To improve the accuracy of the estimated standing current, add the following constraints:

Determine whether the duration of the resting process is greater than the preset value. If it is greater, determine whether the SOC under resting conditions is greater than the SOC under resting conditions at the end of the battery pack;

If it satisfies the calculation of standby current: Pstandby=(SOCstrat-SOCend)*Cap/T;

Determine whether the standing current meets the preset conditions. If so, the calculated standing current is valid.

If the above restrictions are not met, the calculation results are invalid.

In this embodiment, the preset value is set to 24h; the preset condition is that the standing current is less than 500mA.

The invention provides a computer device, including:

Memory, used to store computer programs;

A processor is configured to implement the steps of the above-mentioned adaptive calculation method for battery system resting current when executing a computer program.

For an introduction to the computer device provided by the present invention, please refer to the above method embodiments, and the present invention will not be described again here.

A computer program is stored on the computer-readable storage medium in the present invention. When the computer program is executed by the processor, the steps of the above-mentioned battery system resting current adaptive calculation method are implemented. Storage media include: removable storage devices, read-only memory (ROM), random access memory (RAM), magnetic disks or optical disks and other media that can store program codes.

For an introduction to the computer-readable storage medium provided by the present invention, please refer to the above method embodiments, and the present invention will not be described again here.

Each embodiment in this specification is described in a progressive manner. Each embodiment focuses on its differences from other embodiments. The same and similar parts between the various embodiments can be referred to each other. As for the device disclosed in the embodiment, since it corresponds to the method disclosed in the embodiment, the description is relatively simple. For relevant details, please refer to the description in the method section.

The above description of the disclosed embodiments enables those skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be practiced in other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (8)

1. An adaptive calculation method for battery system resting current, which is characterized by including: S1: Determine whether the current system is in a static state, and if so, determine whether the minimum cell voltage Vmin0 is within the specified voltage range; S2: Determine whether the voltage is stable, and if stable, calculate the minimum cell voltage Vmin1; S3: Calculate the minimum cell voltage Vmin2 after the resting process; S4: According to the minimum cell voltage Vmin1 and the minimum cell voltage Vmin2, obtain the SOC when the battery pack enters the static condition and the SOC when the battery pack ends the static condition, and calculate the static current according to the duration of the static process. 2. A battery system static current adaptive calculation method according to claim 1, characterized in that the specific implementation process of S1 is: Determine whether the sampling current is equal to 0. If the current is equal to 0 at this time, it means that the current system is in a static state; Determine whether the minimum cell voltage Vmin0 is within the range of 3350mv~3550mv or 2800mv~3280mv. If satisfied, proceed to the next step. 3. A battery system static current adaptive calculation method according to claim 1, characterized in that, in S3, the determination principle for the end of the static process is: If there is charging and discharging current, or there is no charging and discharging current, but the balancing mode is activated and it enters the undervoltage state, the resting process is considered to be over. 4. A battery system static current adaptive calculation method according to claim 1, characterized in that the static current calculation formula in S4 is: Pstandby＝(SOCstrat-SOCend)*Cap/T Among them, Pstandby represents the static current, SOCstart represents the SOC of the battery pack when it enters the static condition, SOCend represents the SOC of the battery pack when it ends the static condition, Cap represents the total capacity of the battery pack, and T represents the duration of this static state. 5. An adaptive calculation method for battery system resting current according to claim 1, characterized in that, before calculating the resting current, it further includes: Determine whether the duration of the resting process is greater than the preset value. If it is greater, determine whether the SOC under resting conditions is greater than the SOC under resting conditions at the end of the battery pack; If it satisfies the calculation of the standing current; Determine whether the standing current meets the preset conditions. If so, the calculated standing current is valid. 6. An adaptive calculation method for battery system resting current according to claim 5, characterized in that the preset value is set to 24h; the preset condition is that the resting current is less than 500mA. 7. A computer device, characterized by comprising: Memory, used to store computer programs; A processor, configured to implement the steps of a battery system resting current adaptive calculation method according to any one of claims 1 to 6 when executing the computer program. 8. A computer-readable storage medium, characterized in that a computer program is stored on the computer-readable storage medium, and when the computer program is executed by a processor, the method of any one of claims 1 to 6 is implemented. Steps of adaptive calculation method for battery system resting current.