CN115656843A - Power battery SOC determination method and device, vehicle and storage medium - Google Patents

Abstract

The invention discloses a power battery SOC determination method, device, vehicle and storage medium. The method for determining the SOC of the power battery includes: after the vehicle is powered off, collecting the power battery current data within a set time length, and continuously collecting the target number of times; The average current data of the power battery, and determine the drift current data of the power battery according to the average current data of the power battery; after the vehicle is powered on again, determine the current SOC value of the power battery according to the drift current data of the power battery. The invention realizes effective power battery current correction and eliminates SOC estimation error caused by current error accumulation.

Description

A method, device, vehicle and storage medium for determining the SOC of a power battery

technical field

The present invention relates to the technical field of power battery SOC estimation, in particular to a power battery SOC determination method, device, vehicle and storage medium.

Background technique

BMS (BATTERY MANAGEMENT SYSTEM) battery management system is commonly known as battery nanny or battery steward, mainly for the intelligent management and maintenance of each battery unit, to prevent the battery from overcharging and overdischarging, to prolong the service life of the battery, and to monitor the status of the battery.

One of the core functions of the battery management system is the estimation of SOC (state of charge, state of charge), and the accuracy of SOC estimation greatly affects the performance of the battery management system. Due to the ease of use and good stability of the ampere-hour integration method, most of the SOC estimation methods currently on the market are ampere-hour integration methods. Although the ampere-hour integration method is simple and reliable for estimating SOC, it requires very high accuracy for the current collected by the current sensor. Due to the drift of the current sensor due to factors such as aging, temperature change, and zero drift, the cumulative effect of the acquisition error caused by the drift usually leads to a large error in this open-loop estimation method.

For the drift problem of the current collected by the current sensor, the existing technology usually solves the problem at the hardware level, by determining a fixed value and storing it in the vehicle controller or the current sensor, and passing the collected current value through the pre-stored fixed After the value is corrected, a more accurate value is output. This method can reduce the error of the current sensor to a certain extent, but due to the influence of the instability of the working environment of the vehicle, the inconsistency of the production of parts, and the aging of the parts, it is difficult to continuously ensure the accuracy of the current collection by the method of fixed value correction. sex.

Contents of the invention

The invention provides a power battery SOC determination method, device, vehicle and storage medium to solve the problem that the prior art usually cannot continuously ensure the accuracy of collecting power battery current for a long time, and it is difficult to correct flexibly. In the case of battery current acquisition accuracy, the cumulative error brought by the current accuracy will cause a large deviation in SOC, which will have a great negative impact on the performance of the battery management system.

According to one aspect of the present invention, a method for determining the SOC of a power battery is provided, and the method for determining the SOC of a power battery includes:

When the vehicle is powered off, collect the power battery current data within the set time length, and continuously collect the target times;

Determine the average current data of the power battery collected each time according to the collected current data of the power battery, and determine the drift current data of the power battery according to the average current data of the power battery;

After the entire vehicle is powered on again, the current SOC value of the power battery is determined according to the drift current data of the power battery.

Optionally, the collection of power battery current data within a set period of time includes:

The battery management system of the vehicle delays power-off, and collects the current data of the power battery within a set period of time through the current sensor.

Optionally, the power battery current data includes first to Nth power battery current data; wherein, N is a positive integer greater than or equal to 2;

Determine the average current data of the power battery collected each time according to the collected current data of the power battery, including:

According to the collected current data of the first to Nth power batteries, the corresponding average current values of the first to Nth power batteries are determined.

Optionally, after the determination of the corresponding first to Nth power battery average current values, it further includes:

determining the target power battery average current value according to the first to Nth power battery average current values;

Judging whether the current differences between the first to Nth power battery average current values and the target power battery average current value are all within the first set threshold range, if yes, update the power battery drift current, if not, then do not Update the drift current of the power battery.

Optionally, the method for determining the power battery SOC also includes:

If the collection time corresponding to the average current value of the Nth power battery exceeds the set collection time range, the battery management system is controlled to be powered off.

Optionally, the method for determining the power battery SOC also includes:

If the drift current of the power battery is not updated, it is judged whether the current difference between the average current value of the first to the Nth power battery and the average current value of the target power battery is within the second set threshold range, and if so, it is reported to the current sensor Drift failure, if not, control the battery management system to power off.

Optionally, the determining the current power battery SOC value according to the power battery drift current data includes:

Determine the current power battery SOC value according to the following formula, specifically:

Among them, SOC _t+1 is the current power battery SOC value at t+1 time; SOC _t is the current power battery SOC value at t time; η _i is the power battery charging and discharging Coulombic efficiency; C _max is the maximum available capacity of the current battery; i _L is the collected current value of the power battery current; i ₀ is the drift current data of the power battery; Δt is the time step of collecting the power battery current.

According to another aspect of the present invention, a power battery SOC determination device is provided, and the power battery SOC determination device includes:

The current data acquisition module is used to collect the current data of the power battery within the set time length after the vehicle is powered off, and continuously collect the target times;

The power battery drift current data determination module is used to determine the power battery average current data collected each time according to the collected power battery current data, and determine the power battery drift current data according to the power battery average current data;

The current power battery SOC value determination module is configured to determine the current power battery SOC value according to the power battery drift current data after the vehicle is powered on again.

According to another aspect of the present invention there is provided a vehicle comprising:

at least one processor; and

a memory communicatively coupled to the at least one processor; wherein,

The memory stores a computer program that can be executed by the at least one processor, and the computer program is executed by the at least one processor, so that the at least one processor can execute the method described in any embodiment of the present invention. Method for determining power battery SOC.

According to another aspect of the present invention, a computer-readable storage medium is provided, the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement any of the embodiments of the present invention when executed. The power battery SOC determination method.

According to the technical solution of the embodiment of the present invention, after the vehicle is powered off, the power battery current data within the set time length is collected, and the target number of times is collected continuously; each collection is determined according to the collected power battery current data. The obtained power battery average current data, and determine the power battery drift current data according to the power battery average current data; after the vehicle is powered on again, determine the current power battery SOC value according to the power battery drift current data. The invention solves the problem that the prior art usually cannot continuously guarantee the accuracy of collecting power battery current for a long time, and it is difficult to correct it flexibly. However, if the accuracy of power battery current collection has not been corrected for a long time, the cumulative error caused by the current accuracy will To solve the problem that the SOC has a large deviation, which has a great negative impact on the performance of the battery management system, to achieve effective power battery current correction, and to eliminate the SOC estimation error caused by the accumulation of current errors.

It should be understood that the content described in this section is not intended to identify key or important features of the embodiments of the present invention, nor is it intended to limit the scope of the present invention. Other features of the present invention will be easily understood from the following description.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the drawings that need to be used in the description of the embodiments will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For those skilled in the art, other drawings can also be obtained based on these drawings without creative effort.

FIG. 1 is a flow chart of a method for determining the SOC of a power battery according to Embodiment 1 of the present invention;

Fig. 2 is a flowchart of a method for determining the SOC of a power battery according to Embodiment 2 of the present invention;

Fig. 3 is a flowchart of a method for determining the SOC of a power battery according to Embodiment 3 of the present invention;

Fig. 4 is a schematic structural diagram of a power battery SOC determining device according to Embodiment 4 of the present invention;

Fig. 5 is a schematic structural diagram of a vehicle implementing the method for determining the SOC of a power battery according to an embodiment of the present invention.

Detailed ways

In order to enable those skilled in the art to better understand the solutions of the present invention, the following will clearly and completely describe the technical solutions in the embodiments of the present invention in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only It is an embodiment of a part of the present invention, but not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

It should be noted that the terms "first" and "second" in the description and claims of the present invention and the above drawings are used to distinguish similar objects, but not necessarily used to describe a specific sequence or sequence. It is to be understood that the data so used are interchangeable under appropriate circumstances such that the embodiments of the invention described herein can be practiced in sequences other than those illustrated or described herein. Furthermore, the terms "comprising" and "having", as well as any variations thereof, are intended to cover a non-exclusive inclusion, for example, a process, method, system, product or device comprising a sequence of steps or elements is not necessarily limited to the expressly listed instead, may include other steps or elements not explicitly listed or inherent to the process, method, product or apparatus.

Embodiment one

Figure 1 is a flow chart of a power battery SOC determination method provided by Embodiment 1 of the present invention. This embodiment is applicable to the situation where the estimation accuracy of the power battery SOC is improved, and the power battery SOC determination method can be determined by the power battery SOC. The power battery SOC determining device can be implemented in the form of hardware and/or software, and the power battery SOC determining device can be configured in a vehicle or a vehicle controller. As shown in Figure 1, the method for determining the SOC of the power battery includes:

S110. After the entire vehicle is powered off, collect the current data of the power battery within a set time length, and continuously collect the target number of times.

After the vehicle is powered off, that is, after the vehicle stops, the driver of the vehicle pulls out the key, and the vehicle power battery has no power output or input. At this time, the battery management system of the vehicle delays power off, and the current sensor can control The current continues to be collected and recorded.

It can be understood that since the vehicle is powered off and the vehicle power battery has no power output or input, the current data of the power battery collected at this time contains error information. This embodiment corrects the current error to improve the power of the subsequent power battery. SOC value estimation accuracy.

Wherein, both the set time length of collection and the target number of collections can be selected and set by those skilled in the art according to the actual situation, which is not limited in this embodiment. Optionally, set the time length as 1 minute, 2 minutes or several minutes, and the target number of times is a positive integer greater than or equal to 2. In order to ensure the validity of the power battery current data acquisition and ensure the accuracy of the power battery SOC value estimation, you can choose The target number of times is 3 times.

Specifically, continuously collect the power battery current data within the nth minute, within the n+1th minute..., wherein, n is a positive integer greater than or equal to 1, and further, collect the target number of times k, that is, continuously collect the nth minute Within, within the n+1th minute...the power battery current data within the n+k-1th minute, where k is a positive integer greater than or equal to 1.

In this embodiment, the continuous collection of power battery current data within the nth minute, within the n+1th minute ... within the n+k-1th minute is defined as the first to Nth power battery current data, wherein, N is a positive integer greater than or equal to 2.

Exemplarily, taking the target number of times as 3, n being 1, and k being 3 as an example, the current data of the power battery within the first minute, the second minute, and the third minute are continuously collected to obtain the first power battery current data , the current data of the second power battery, and the current data of the third power battery.

S120. Determine the average current data of the power battery collected each time according to the collected current data of the power battery, and determine the drift current data of the power battery according to the average current data of the power battery.

On the basis of the above, the calculation of the average current data of the power battery can be obtained by calculating the step time according to the ampere-hour integration method, and the ampere-hour integration correction is performed on the current data of the power battery collected each time, so as to make up for the ampere-hour integration method that is susceptible to cumulative errors. Influence.

Exemplarily, the data of the first 30 seconds of each power battery current data can be selected, and other time lengths can also be selected. The length of the specifically selected power battery current data can be selected and set by those skilled in the art according to the actual situation. This embodiment No restrictions are imposed.

Exemplarily, taking the target number of times as 3, n as 1, and k as 3 as an example, continuously collect the power battery current data within the first minute, within the second minute, and within the third minute, and select the first 30 seconds within the first minute According to the current data of the first power battery, calculate the step length according to the ampere-hour integration method to obtain the average current value of the first power battery, select the current data of the second power battery within the first 30 seconds within the second minute, and calculate the step length according to the ampere-hour integration method Time to get the average current value of the second power battery, select the current data of the third power battery in the first 30 seconds within the first 3 minutes, and calculate the step time according to the ampere-hour integration method to get the average current value of the third power battery.

Further, the target power battery average current value is determined according to the first to Nth power battery average current values, and the target power battery average current value is the average value of all power battery average current values, effectively ensuring the stability of the screened power battery current correction value sex, reliability.

When it is judged that the current differences between the first to Nth power battery average current values and the target power battery average current value are all in the first set threshold range, the target power battery average current value is positioned as the current power The battery drift current data is to update the power battery drift current stored in the vehicle's battery management system.

It can be understood that if it is determined that the current difference between the first to Nth power battery average current values and the target power battery average current value is not within the first set threshold range, the power battery drift cannot be satisfied. The target power battery average current value of the current update condition, at this time, continue to use the original power battery drift current stored in the vehicle's battery management system.

S130. After the entire vehicle is powered on again, determine the current SOC value of the power battery according to the drift current data of the power battery.

Specifically, when the vehicle is woken up again, that is, after the vehicle is powered on again, if the drift current of the power battery stored in the battery management system of the vehicle has been updated, the current power is determined according to the updated current data of the drift current of the power battery. Battery SOC value, that is, determine the current power battery SOC value according to the target power battery average current value; if the power battery drift current stored in the vehicle's battery management system has not been updated, then determine the current power battery SOC value according to the original power battery drift current.

It can be seen that the discretized ampere-hour integral formula for power battery SOC value estimation used in practice is specifically:

Among them, SOC _t+1 is the SOC value of the power battery at time t+1; SOC _t is the SOC value of the power battery at time t; η _i is the coulombic efficiency of charging and discharging the power battery; C _max is the maximum available capacity of the current power battery; i _L is the collected current value of the power battery current; Δt is the time step of collecting the power battery current.

In this embodiment, after the vehicle is powered on again, the current power battery SOC value is determined according to the following formula, specifically:

Wherein, i ₀ is the drift current data of the power battery.

It should be noted that when using the ampere-hour integration method to calculate the SOC value of the power battery, a drift correction is performed on the collected power battery current at each step, so that when the SOC value of the power battery has not been calibrated for a long time , to eliminate the cumulative deviation caused by the current drift error of the acquisition power battery.

According to the technical solution of the embodiment of the present invention, after the vehicle is powered off, the power battery current data within the set time length is collected, and the target number of times is collected continuously; each collection is determined according to the collected power battery current data. The obtained power battery average current data, and determine the power battery drift current data according to the power battery average current data; after the vehicle is powered on again, determine the current power battery SOC value according to the power battery drift current data. The invention solves the problem that the prior art usually cannot continuously guarantee the accuracy of collecting power battery current for a long time, and it is difficult to correct it flexibly. However, if the accuracy of power battery current collection has not been corrected for a long time, the cumulative error caused by the current accuracy will To solve the problem that the SOC has a large deviation, which has a great negative impact on the performance of the battery management system, to achieve effective power battery current correction, and to eliminate the SOC estimation error caused by the accumulation of current errors.

Embodiment two

Fig. 2 is a flow chart of a method for determining the SOC of a power battery provided by Embodiment 2 of the present invention. On the basis of the above embodiment, this embodiment further improves step S120 as follows: according to the collected first to Nth power batteries Current data, determine the corresponding average current value of the first to the Nth power battery; determine the average current value of the target power battery according to the average current value of the first to the Nth power battery; determine the average current value of the first to the Nth power battery Whether the current difference of the target power battery average current value is within the first set threshold range, if yes, update the power battery drift current, if not, do not update the power battery drift current. As shown in Figure 2, the method for determining the power battery SOC includes:

S210. After the entire vehicle is powered off, the battery management system of the vehicle delays power off, and collects the power battery current data within a set time length through the current sensor, wherein the power battery current data includes the first to the second N power battery current data; where, N is a positive integer greater than or equal to 2.

It can be seen that the power battery SOC determination method corrects the acquisition current error, does not depend on hardware, and has good versatility. Among them, the current sensor can be a shunt, a Hall sensor, etc., and has good universality.

In this solution, the current data of the power battery is collected immediately after the vehicle stops and is powered off. At this time, the temperature state of the controller maintains a good consistency with the temperature state of the vehicle when it is running, effectively avoiding the problem of collecting power battery current data at different temperatures caused by temperature changes. Current drift, which in turn leads to additional SOC cumulative errors.

S220. Determine the corresponding average current values of the first to Nth power batteries according to the collected current data of the first to Nth power batteries.

S230. Determine the target power battery average current value according to the first to Nth power battery average current values.

S240. Determine whether the current difference between the first to Nth power battery average current values and the target power battery average current value is within the first set threshold range, if yes, execute step S250, if not, execute Step S260.

Wherein, the first set threshold range can be selected and set by those skilled in the art according to the actual situation, and this embodiment does not impose any limitation on it.

The first set threshold value range is used as the conditional threshold value to ensure the stability and reliability of drift fault correction achieved by the collected power battery current, the average current value of the first power battery ... the average current value of the Nth power battery is respectively the same as the As long as the current difference between the target power battery average current values is not within the first set threshold range, the power battery drift current may not be updated to ensure the reliability of the power battery drift current.

S250. Update the drift current of the power battery, update the target average current value of the power battery to the battery management system of the vehicle, and execute step S280.

S260. Execute step S270 without updating the drift current of the power battery.

S270. Determine whether the current difference between the average current values of the first to Nth power batteries and the target power battery average current value is within the second set threshold range. If yes, execute step S280; if not, execute step S270. S271.

Wherein, the second set threshold range can be selected and set by those skilled in the art according to the actual situation, and this embodiment does not impose any limitation on it.

The second set threshold range can be used as a conditional threshold for further judging whether a large error occurs in the current sensor, if the current difference between the first to Nth power battery average current values and the target power battery average current value is within the first 2. If the threshold range is set, the drift fault of the current sensor will be reported.

It should be noted that the second set threshold range is a larger threshold range than the first set threshold range, the second set threshold range is greater than the first set threshold range, and the second set threshold range can be greater than a certain threshold range. Multiples of the current value, indicating that there is a large error in the drift of the current sensor, then a drift fault of the current sensor will be reported.

S271. Report the drift fault of the current sensor, and execute step S280.

It can be seen that when the current sensor drift fault is reported, the collection of the power battery current is stopped, and the battery management system is controlled to be powered off.

S280. Control the battery management system to be powered off, and execute step S290.

Specifically, stop collecting power battery current, and control the battery management system to power off.

S290. After the entire vehicle is powered on again, determine the current SOC value of the power battery according to the drift current data of the power battery.

Embodiment three

Fig. 3 is a flowchart of a power battery SOC determination method provided by Embodiment 3 of the present invention. On the basis of the above embodiment, taking the target number of times as 3, n as 1, and k as 3 as an example, continuously collect data for the first minute The current data of the power battery within the second minute and the third minute, that is, the current data of the first power battery, the current data of the second power battery, and the current data of the third power battery, provide an optional implementation mode. As shown in Figure 3, the method for determining the power battery SOC includes:

S310. Continuously collect the current data of the first power battery, the current data of the second power battery, and the current data of the third power battery within a set time length.

S311. According to the collected first power battery current data, second power battery current data, and third power battery current data, determine the corresponding first power battery average current value i ₁ , second power battery average current value i ₂ , The average current value i ₃ of the third power battery.

S312. Determine the target power battery average current value i _ave according to the first power battery average current value i ₁ , the second power battery average current value i ₂ , and the third power battery average current value i ₃ .

S313. Judging whether the current difference between the first power battery average current value i ₁ , the second power battery average current value i ₂ , the third power battery average current value i ₃ and the target power battery average current value i _ave are all in the first A threshold range is set, if yes, execute step S314, if not, execute step S310.

Specifically, according to the current difference between the first power battery average current value i ₁ , the second power battery average current value i ₂ , the third power battery average current value i ₃ and the target power battery average current value i _ave , none of If it is within the first set threshold range, that is, the target power battery average current value i _ave that meets the set conditions is not obtained, then record the power battery current data within the next minute again, which can be recorded as the fourth power battery current data, and Further determine the corresponding fourth power battery average current value i ₄ , and then judge again based on the second power battery average current value i ₂ , the third power battery average current value i ₃ , the fourth power battery average current value i ₄ and the target power Whether the current difference of the battery average current value i _ave is in the first set threshold range, if it is satisfied, then proceed to the operation of step S314; If the power battery current data can meet the above requirements, the next step can be continued.

In this embodiment, the collected power battery current is taken at three intervals to obtain the average current value of each step, that is, the first power battery average current value i ₁ , the second power battery average current value i 2 , the third power battery average current value i ₂ , and the third power battery average current value are obtained. current value i ₃ , and calculate the average value of the average current value for three consecutive times to obtain the target power battery average current value i _ave , when the average current value for three consecutive times and its average value remain within the specified Z% error (that is, the first set threshold range ), the drift current of the power battery is updated, and the target power battery average current value i _ave is taken as the drift current correction value. The average of such processing effectively ensures the high reliability of the obtained drift current correction value, and the drift current correction value that satisfies the conditions has not been obtained after exceeding the specified time, so it will not be updated this time.

S314 , judging whether the time for determining the target power battery average current value i _ave exceeds the set collection time range, if yes, execute step S316 , if not, execute step S315 .

On the basis of the above, it should be noted that the time for determining the target power battery average current value i _ave exceeds the set collection time range, that is, when the fourth power battery current data or the Nth power battery current data corresponds to If the acquisition time exceeds the set acquisition time range, the acquisition of the power battery current data will be stopped, and the target power battery average current value i _ave currently available will be used as the data of the subsequent execution steps, instead of cyclically collecting the power battery current to obtain the satisfaction of the steps The target power battery average current value i _ave of the condition of S313 , and control the battery management system to be powered off.

It can be understood that, setting the acquisition time range may be selected and set by those skilled in the art according to actual conditions, and this embodiment does not impose any limitation on this.

S315. Update the drift current of the power battery, update the target average current value of the power battery to the battery management system of the vehicle, and execute step S319.

S316. Execute step S317 without updating the drift current of the power battery.

S317. Judging whether the current difference between the first power battery average current value i ₁ , the second power battery average current value i ₂ , the third power battery average current value i ₃ and the target power battery average current value i _ave are all in the first 2. Set the threshold range. If yes, execute step S319; if not, execute step S318.

On the basis of the above, set the second set threshold range, for the calculated average current value i ₁ of the first power battery, the average current value i ₂ of the second power battery, the average current value i ₃ of the third power battery and its target power battery If the difference of the average current value i _ave is too large, it exceeds the specified multiple X (the specified multiple X is the second set threshold range), then it means that the current drift of the current sensor is too large at this time, and the current sensor will be reported Acquisition drift failure.

S318. Report the drift fault of the current sensor, and execute step S319.

S319. Control the battery management system to be powered off, and execute step S320.

S320. After the entire vehicle is powered on again, determine the current SOC value of the power battery according to the drift current data of the power battery.

Embodiment four

Fig. 4 is a schematic structural diagram of a power battery SOC determining device provided in Embodiment 4 of the present invention. As shown in Figure 4, the power battery SOC determination device includes:

The current data acquisition module 410 is used to collect the current data of the power battery within a set time length after the vehicle is powered off, and continuously collect the target number of times;

The power battery drift current data determination module 420 is configured to determine the power battery average current data collected each time according to the collected power battery current data, and determine the power battery drift current data according to the power battery average current data;

The current power battery SOC value determination module 430 is configured to determine the current power battery SOC value according to the power battery drift current data after the vehicle is powered on again.

Optionally, the collection of power battery current data within a set period of time includes:

The battery management system of the vehicle delays power-off, and collects the current data of the power battery within a set period of time through the current sensor.

Optionally, the power battery current data includes first to Nth power battery current data; wherein, N is a positive integer greater than or equal to 2;

Determine the average current data of the power battery collected each time according to the collected current data of the power battery, including:

According to the collected current data of the first to Nth power batteries, the corresponding average current values of the first to Nth power batteries are determined.

Optionally, after the determination of the corresponding first to Nth power battery average current values, it further includes:

determining the target power battery average current value according to the first to Nth power battery average current values;

Judging whether the current differences between the first to Nth power battery average current values and the target power battery average current value are all within the first set threshold range, if yes, update the power battery drift current, if not, then do not Update the drift current of the power battery.

Optionally, the power battery SOC determining device further includes:

The collection time judging module is used to control the battery management system to power off if the collection time corresponding to the average current value of the Nth power battery exceeds the set collection time range.

Optionally, the power battery SOC determining device further includes:

Continue to the judging module, which is used to judge whether the current difference between the first to Nth power battery average current values and the target power battery average current value is within the second set threshold range when the drift current of the power battery is not updated , if yes, report the current sensor drift fault, if not, control the battery management system to power off.

Optionally, the determining the current power battery SOC value according to the power battery drift current data includes:

Determine the current power battery SOC value according to the following formula, specifically:

Among them, SOC _t+1 is the current power battery SOC value at t+1 time; SOC _t is the current power battery SOC value at t time; η _i is the power battery charging and discharging Coulombic efficiency; C _max is the maximum available capacity of the current battery; i _L is the collected current value of the power battery current; i0 is the drift current data of the power battery; Δt is the time step of collecting the power battery current.

The power battery SOC determination device provided in the embodiments of the present invention can execute the power battery SOC determination method provided in any embodiment of the present invention, and has corresponding functional modules and beneficial effects for performing the power battery SOC determination method.

Embodiment five

FIG. 5 shows a schematic structural diagram of a vehicle 510 that can be used to implement an embodiment of the present invention. Vehicles include various forms of digital computers, such as laptops, desktops, workstations, personal digital assistants, servers, blade servers, mainframes, and other suitable computers. Vehicles may also include mobile devices representing various forms, such as personal digital processing, cellular phones, smartphones, wearable devices (eg, helmets, glasses, watches, etc.), and other similar computing devices. The components shown herein, their connections and relationships, and their functions, are by way of example only, and are not intended to limit implementations of the inventions described and/or claimed herein.

As shown in FIG. 5 , a vehicle 510 includes at least one processor 511, and a memory communicatively connected to at least one processor 511, such as a read-only memory (ROM) 512, a random access memory (RAM) 513, etc., wherein the memory stores A computer program executable by at least one processor, the processor 511 can be executed according to a computer program stored in a read only memory (ROM) 512 or a computer program loaded from a storage unit 518 into a random access memory (RAM) 513 Various appropriate actions and treatments. In the RAM 513, various programs and data necessary for the operation of the vehicle 510 are also stored. The processor 511 , ROM 512 , and RAM 513 are connected to each other through a bus 514 . Input/output (I/O interface 515 ) is also connected to bus 514 .

Multiple components in the vehicle 510 are connected to the I/O interface 515, including: an input unit 516, such as a keyboard, a mouse, etc.; an output unit 517, such as various types of displays, speakers, etc.; a storage unit 518, such as a magnetic disk, an optical disk, etc. ; and a communication unit 519, such as a network card, a modem, a wireless communication transceiver, and the like. The communication unit 519 allows the vehicle 510 to exchange information/data with other devices through a computer network such as the Internet and/or various telecommunication networks.

Processor 511 may be various general and/or special purpose processing components having processing and computing capabilities. Some examples of processor 511 include, but are not limited to, central processing units (CPUs), graphics processing units (GPUs), various specialized artificial intelligence (AI) computing chips, various processors that run machine learning model algorithms, digital signal processing processor (DSP), and any suitable processor, controller, microcontroller, etc. The processor 511 executes various methods and processes described above, such as a method for determining the SOC of a power battery.

In some embodiments, the method for determining the SOC of a power battery can be implemented as a computer program, which is tangibly contained in a computer-readable storage medium, such as the storage unit 518 . In some embodiments, part or all of the computer program may be loaded and/or installed on the vehicle 510 via the ROM 512 and/or the communication unit 519 . When the computer program is loaded into the RAM 513 and executed by the processor 511, one or more steps of the method for determining the power battery SOC described above can be executed. Alternatively, in other embodiments, the processor 511 may be configured in any other appropriate way (for example, by means of firmware) to execute the method for determining the SOC of the power battery.

Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips Implemented in a system of systems (SOC), load programmable logic device (CPLD), computer hardware, firmware, software, and/or combinations thereof. These various embodiments may include being implemented in one or more computer programs executable and/or interpreted on a programmable system including at least one programmable processor, the programmable processor Can be special-purpose or general-purpose programmable processor, can receive data and instruction from storage system, at least one input device, and at least one output device, and transmit data and instruction to this storage system, this at least one input device, and this at least one output device an output device.

Computer programs for implementing the methods of the present invention may be written in any combination of one or more programming languages. These computer programs can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus, so that the computer program causes the functions/operations specified in the flowcharts and/or block diagrams to be implemented when executed by the processor. A computer program may execute entirely on the machine, partly on the machine, as a stand-alone software package partly on the machine and partly on a remote machine or entirely on the remote machine or server.

In the context of the present invention, a computer readable storage medium may be a tangible medium that may contain or store a computer program for use by or in conjunction with an instruction execution system, apparatus or device. A computer readable storage medium may include, but is not limited to, electronic, magnetic, optical, electromagnetic, infrared, or semiconductor systems, apparatus, or devices, or any suitable combination of the foregoing. Alternatively, a computer readable storage medium may be a machine readable signal medium. More specific examples of machine-readable storage media would include one or more wire-based electrical connections, portable computer discs, hard drives, random access memory (RAM), read only memory (ROM), erasable programmable read only memory (EPROM or flash memory), optical fiber, compact disk read only memory (CD-ROM), optical storage, magnetic storage, or any suitable combination of the foregoing.

To provide interaction with the user, the systems and techniques described herein can be implemented on a vehicle having a display device (e.g., a CRT (cathode ray tube) or LCD (liquid crystal display) monitor) for displaying information to the user ); and a keyboard and pointing device (eg, a mouse or trackball) through which the user may provide input to the vehicle. Other kinds of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and can be in any form (including Acoustic input, speech input or, tactile input) to receive input from the user.

The systems and techniques described herein can be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., as a a user computer having a graphical user interface or web browser through which a user can interact with embodiments of the systems and techniques described herein), or including such backend components, middleware components, Or any combination of front-end components in a computing system. The components of the system can be interconnected by any form or medium of digital data communication, eg, a communication network. Examples of communication networks include: local area networks (LANs), wide area networks (WANs), blockchain networks, and the Internet.

A computing system can include clients and servers. Clients and servers are generally remote from each other and typically interact through a communication network. The relationship of client and server arises by computer programs running on the respective computers and having a client-server relationship to each other. The server can be a cloud server, also known as a cloud computing server or a cloud host. It is a host product in the cloud computing service system to solve the problems of difficult management and weak business expansion in traditional physical hosts and VPS services. defect.

It should be understood that steps may be reordered, added or deleted using the various forms of flow shown above. For example, each step described in the present invention may be executed in parallel, sequentially, or in a different order, as long as the desired result of the technical solution of the present invention can be achieved, there is no limitation herein.

The above specific implementation methods do not constitute a limitation to the protection scope of the present invention. It should be apparent to those skilled in the art that various modifications, combinations, sub-combinations and substitutions may be made depending on design requirements and other factors. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention shall be included within the protection scope of the present invention.

Claims (10)

1. A method for determining the SOC of a power battery, comprising: When the vehicle is powered off, collect the power battery current data within the set time length, and continuously collect the target times; Determine the average current data of the power battery collected each time according to the collected current data of the power battery, and determine the drift current data of the power battery according to the average current data of the power battery; After the entire vehicle is powered on again, the current SOC value of the power battery is determined according to the drift current data of the power battery. 2. The method for determining the SOC of a power battery according to claim 1, wherein the collecting the power battery current data within a set time length includes: The battery management system of the vehicle delays power-off, and collects the current data of the power battery within a set period of time through the current sensor. 3. The method for determining the SOC of a power battery according to claim 1, wherein the power battery current data includes the first to Nth power battery current data; wherein, N is a positive integer greater than or equal to 2; Determine the average current data of the power battery collected each time according to the collected current data of the power battery, including: According to the collected current data of the first to Nth power batteries, the corresponding average current values of the first to Nth power batteries are determined. 4. The power battery SOC determination method according to claim 3, characterized in that, after said determining the corresponding first to Nth power battery average current values, further comprising: determining the target power battery average current value according to the first to Nth power battery average current values; Judging whether the current differences between the first to Nth power battery average current values and the target power battery average current value are all within the first set threshold range, if yes, update the power battery drift current, if not, then do not Update the drift current of the power battery. 5. The power battery SOC determination method according to claim 4, wherein the power battery SOC determination method further comprises: If the collection time corresponding to the average current value of the Nth power battery exceeds the set collection time range, the battery management system is controlled to be powered off. 6. The power battery SOC determination method according to claim 4, wherein the power battery SOC determination method further comprises: When the drift current of the power battery is not updated, it is judged whether the current difference between the average current value of the first to the Nth power battery and the average current value of the target power battery is within the second set threshold range, and if so, the current is reported Sensor drift failure, if not, control the battery management system to power off. 7. The method for determining the power battery SOC according to claim 1, wherein the determining the current power battery SOC value according to the power battery drift current data includes: Determine the current power battery SOC value according to the following formula, specifically:

Among them, SOC _t+1 is the current power battery SOC value at t+1 time; SOC _t is the current power battery SOC value at t time; η _i is the power battery charging and discharging Coulombic efficiency; C _max is the maximum available capacity of the current battery; i _L is the collected current value of the power battery current; i ₀ is the drift current data of the power battery; Δt is the time step of collecting the power battery current. 8. A device for determining the SOC of a power battery, comprising: The current data acquisition module is used to collect the current data of the power battery within the set time length after the vehicle is powered off, and continuously collect the target times; The power battery drift current data determination module is used to determine the power battery average current data collected each time according to the collected power battery current data, and determine the power battery drift current data according to the power battery average current data; The current power battery SOC value determination module is configured to determine the current power battery SOC value according to the power battery drift current data after the vehicle is powered on again. 9. A vehicle, characterized in that the vehicle comprises: at least one processor; and a memory communicatively coupled to the at least one processor; wherein, The memory stores a computer program executable by the at least one processor, the computer program is executed by the at least one processor, so that the at least one processor can perform any one of claims 1-7 The method for determining the SOC of a power battery. 10. A computer-readable storage medium, wherein the computer-readable storage medium stores computer instructions, and the computer instructions are used to enable a processor to implement the method described in any one of claims 1-7 when executed. Method for determining power battery SOC.

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