Estimation method, device, electronic device and storage medium

Abstract

The embodiment of the present application discloses an estimation method, including: testing a battery to obtain the current value of the battery voltage and the current value of the battery current, performing Kalman filtering on the obtained current value of the battery's equivalent ohmic internal resistance, the current value of the battery voltage, and the current value of the battery current to obtain the current value of the battery's State of Charge (SOC), and when the battery is discharged and the current value of the battery's SOC falls within a preset range, performing Kalman filtering on the current value of the battery's SOC, the current value of the battery voltage, and the current value of the battery current to estimate the current value of the battery's State of Charge (SOH). The embodiment of the present application also discloses an estimation device, an electronic device, and a storage medium.

Description

Technical Field

[0001] The present application relates to the technical field of battery state of health (SOH) estimation, and in particular to an estimation method, device, electronic device, and storage medium. Background Art

[0002] Currently, battery life estimation generally uses experimentally measured battery aging curves or Kalman filtering to estimate the battery's SOH. However, this estimation method has poor accuracy.

[0003] Application Contents

[0004] The embodiments of the present application hope to provide an estimation method, apparatus, electronic device, storage medium and device to solve the problem of poor accuracy in battery SOH estimation in related technologies.

[0005] The technical solution of this application is achieved as follows:

[0006] An estimation method comprising:

[0007] Detecting the battery to obtain a current value of the battery voltage and a current value of the battery current;

[0008] Performing Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain a current value of the SOC of the battery;

[0009] When the battery is discharged and the current value of the battery's SOC falls within a preset range, Kalman filtering is performed on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to estimate the current value of the battery's SOH.

[0010] An estimation device comprising:

[0011] a detection module, configured to detect the battery and obtain a current value of the battery voltage and a current value of the battery current;

[0012] a filtering module, configured to perform Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain a current value of the SOC of the battery;

[0013] An estimation module is used to perform Kalman filtering on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current when the battery is discharged and the current value of the battery's SOC falls within a preset range, so as to estimate the current value of the battery's SOH.

[0014] An electronic device, comprising:

[0015] A processor and a storage medium storing instructions executable by the processor, wherein the storage medium relies on the processor to perform operations via a communication bus, and when the instructions are executed by the processor, the estimation method described in one or more of the above embodiments is executed.

[0016] A storage medium stores one or more programs, wherein the one or more programs can be executed by one or more processors to implement the estimation method described in one or more embodiments above.

[0017] The estimation method, device, electronic device and storage medium provided in the embodiments of the present application include: detecting the battery to obtain the current value of the battery voltage and the current value of the battery current, performing Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the battery voltage and the current value of the battery current to obtain the current value of the SOC of the battery; when the battery is discharged and the current value of the SOC of the battery falls within a preset range, performing Kalman filtering on the current value of the SOC of the battery, the current value of the battery voltage and the current value of the battery current to estimate the current value of the SOH of the battery; that is, in the embodiments of the present application, the current value of the battery voltage, the current value of the battery current and the equivalent ohmic internal resistance of the battery obtained by detecting the battery are obtained. The current value of the battery's SOC is estimated by Kalman filtering, and the current value of the battery's SOC, the detected current value of the battery's voltage, and the current value of the battery's current are estimated more accurately than by directly performing Kalman filtering on the current value of the battery's SOC, the detected current value of the battery's voltage, and the current value of the battery's current. In this way, the battery life can be estimated more accurately by judging the battery state and the current value of the battery's SOC, and using Kalman filtering to estimate the current value of the battery's SOH when the battery is discharged and the current value of the battery's SOC falls within a preset range. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 A flowchart of an optional estimation method provided in an embodiment of the present application;

[0019] Figure 2 A flowchart of an example of an optional estimation method provided in an embodiment of the present application;

[0020] Figure 3 A schematic diagram of the structure of a battery collection system provided in an embodiment of the present application;

[0021] Figure 4a A flowchart of an example of another optional estimation method provided in an embodiment of the present application;

[0022] Figure 4b A flowchart of an example of another optional estimation method provided in an embodiment of the present application;

[0023] Figure 5 A schematic structural diagram of an optional estimation device provided in an embodiment of the present application;

[0024] Figure 6 A schematic structural diagram of an optional electronic device provided in an embodiment of the present application. DETAILED DESCRIPTION

[0025] In order to better understand the purpose, structure and function of the present application, the following is a further detailed description of an estimation method, device, electronic device and storage medium of the present application in conjunction with the accompanying drawings.

[0026] The embodiment of the present application provides an estimation method, Figure 1 A flow chart of an optional estimation method provided in the embodiment of the present application is provided. Figure 1 As shown, the method may include:

[0027] S101: Detect the battery to obtain the current value of the battery voltage and the current value of the battery current;

[0028] Currently, estimating the SOH of a battery by using an experimentally measured battery aging curve or Kalman filtering has a technical problem of poor accuracy. In order to improve the accuracy of the SOH of a battery, an embodiment of the present application proposes an estimation method for estimating the SOH of a battery, where the battery is usually a rechargeable battery.

[0029] In S101, the battery is tested to obtain the current value of the battery voltage and the current value of the battery current. It should be noted that the battery test may be the current value of the battery voltage and the current value of the battery current obtained by testing the battery when the battery is in a charging state, or the current value of the battery voltage and the current value of the battery current obtained by testing the battery when the battery is in a discharging state. This embodiment of the present application does not specifically limit this.

[0030] S102: performing Kalman filtering on the acquired current value of the equivalent ohmic internal resistance of the battery, the current value of the battery voltage, and the current value of the battery current to obtain a current value of the battery SOC;

[0031] After obtaining the current value of the battery voltage and the current value of the battery current, the current value of the battery's equivalent ohmic resistance is obtained, and then the current value of the battery's equivalent ohmic internal resistance, the current value of the battery's voltage, and the current value of the battery's current are subjected to Kalman filtering to obtain the current value of the battery's SOC. It should be noted here that the initial value of the current value of the battery's equivalent ohmic internal resistance is the initial value of the battery's equivalent ohmic internal resistance, and the current value of the battery's SOC can be calculated using S102.

[0032] S103: When the battery is discharged and the current value of the battery's SOC falls within a preset range, Kalman filtering is performed on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to estimate the current value of the battery's SOH.

[0033] After the current value of the battery's SOC is calculated through S102, the battery status and the current value of the battery's SOC are judged. Only when the battery is discharged and the current value of the battery's SOC falls within a preset range, the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current are Kalman filtered to obtain the current value of the battery's SOH.

[0034] Here, it should be noted that, in performing Kalman filtering on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to obtain the current value of the battery's SOH, the current value of the battery's equivalent ohmic internal resistance can be first retrieved through Kalman filtering. In this way, the current value of the battery's equivalent ohmic internal resistance can be continuously updated, and then the current value of the battery's SOH can be obtained using the retrieved current value of the battery's equivalent ohmic internal resistance, so as to achieve the purpose of continuously updating the current value of the battery's SOH.

[0035] By continuously updating the current value of the battery's equivalent ohmic internal resistance and the current value of the battery's SOC, the current value of the battery's SOH is re-estimated only when the battery is discharged and the current value of the battery's SOC falls within a preset range. That is to say, the embodiment of the present application mainly imposes conditional restrictions on the Kalman filter processing for estimating the current value of the battery's SOH, limiting the estimation to when the battery is discharged and the current value of the battery's SOH falls within a preset range. In this way, the estimation accuracy of the battery's SOH can be improved.

[0036] Furthermore, in order to improve estimation accuracy, in an optional embodiment, S101 may include:

[0037] Detect the battery to obtain the current voltage detection value and the current current detection value of the battery;

[0038] Obtain the first M voltage detection values ​​of the battery, the last N voltage detection values ​​of the battery, the first M current detection values ​​of the battery, and the last N current detection values ​​of the battery;

[0039] Based on the current voltage detection value, determine the number of voltage detection values ​​that have changed between the previous M voltage detection values ​​and the next N voltage detection values;

[0040] Based on the current detection value, determine the number of current detection values ​​that have changed between the previous M current detection values ​​and the next N current detection values;

[0041] When the sum of the number of changed voltage detection values ​​and the number of changed current detection values ​​is less than a first preset threshold, the current voltage detection value is determined as the current value of the battery voltage, and the current current detection value is determined as the current value of the battery current.

[0042] It can be understood that by testing the battery, the current voltage detection value of the battery and the current current detection value of the battery can be obtained, and the current voltage detection value of the battery and the current current detection value of the battery can be screened. The main screening method can be to screen the current voltage detection value of the battery and the current current detection value of the battery detected this time based on the first M voltage detection values ​​of the battery, the last N voltage detection values ​​of the battery, the first M current detection values ​​of the battery and the last N current detection values ​​of the battery.

[0043] For the screening of voltage detection values, the current voltage detection value is used as a reference to determine the number of voltage detection values ​​that have changed between the previous M voltage detection values ​​and the next N voltage detection values. Similar to the screening of voltage detection values, the current current detection value is used as a reference to determine the number of current detection values ​​that have changed between the previous M current detection values ​​and the next N current detection values. The sum of the number of changed voltage detection values ​​and the number of changed current detection values ​​is calculated, and then the sum is compared to see whether it is less than the first preset threshold value. If so, the current voltage detection value is determined as the current value of the battery voltage, and the current current detection value is determined as the current value of the battery current. That is, the voltage value and current value obtained in this detection are retained to estimate the battery SOH.

[0044] If it is greater than, the voltage and current values ​​obtained in this detection are not used to estimate the battery SOH. For the case where they are equal, the voltage and current values ​​obtained in this detection are retained to estimate the battery SOH. Alternatively, the voltage and current values ​​obtained in this detection may not be used to estimate the battery SOH. Here, the embodiments of the present application do not make specific limitations on this.

[0045] In order to improve estimation accuracy, in an optional embodiment, the first preset threshold is 0.

[0046] That is to say, for the current voltage detection value and the current current detection value, the voltage detection values ​​of the first M times and the voltage detection values ​​of the last N times are the same relative to the current voltage detection value and have not changed. The current detection values ​​of the first M times and the current detection values ​​of the last N times are the same relative to the current current detection value and have not changed. In this way, the current voltage detection value is determined as the current voltage value of the battery, and the current current detection value is determined as the current current value of the battery, so as to estimate the SOH of the battery.

[0047] Among them, the above M and N can usually be selected as 2.

[0048] In order to estimate the current value of the battery's SOH, in an optional embodiment, S103 may include:

[0049] When the battery is discharged and the current value of the battery's SOC falls within a preset range, a Kalman filter is performed on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to obtain a calculated value of the battery's SOH;

[0050] When the calculated value of the battery's SOH is less than the current value of the battery's SOH, the current value of the battery's SOH is estimated based on the calculated value of the battery's SOH.

[0051] It can be understood that when the battery is discharged and the current value of the battery's SOC falls within a preset range, the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current are subjected to Kalman filtering to obtain a calculated value of the battery's SOH. This calculated value may be greater than or less than the current value of the battery's SOH. Since the battery's SOH usually becomes smaller over time, here, only when the calculated value of the battery's SOH is less than the current value of the battery's SOH, is the current value of the battery's SOH estimated based on the calculated value of the battery's SOH.

[0052] It should be noted that the initial value of the current value of the SOH of the battery is usually set to 100%.

[0053] Furthermore, in order to improve the estimation accuracy, in an optional embodiment, a Kalman filter process is performed on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain a calculated value of the battery SOH, including:

[0054] Perform Kalman filtering on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to-be-processed equivalent ohmic internal resistance to obtain the current value to-be-processed of the battery's equivalent ohmic internal resistance, and update i to i+1; where i is the number of the current values ​​to-be-processed of the battery's equivalent ohmic internal resistance, and the initial value of i is 0;

[0055] When i is equal to a second preset threshold, based on the current pending value of the equivalent ohmic internal resistance of the battery, an average value algorithm is called to determine the current value of the equivalent ohmic internal resistance of the battery, i is updated to 0, the current pending value of the equivalent ohmic internal resistance of the battery is cleared, and the process returns to perform Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain the current pending value of the equivalent ohmic internal resistance of the battery;

[0056] When i is less than a second preset threshold, returning to execute battery detection to obtain a current value of the battery voltage and a current value of the battery current;

[0057] The current value of the equivalent ohmic internal resistance of the battery is processed by Kalman filtering to obtain the calculated value of the SOH of the battery.

[0058] That is to say, in using Kalman filtering to obtain the calculated value of the battery's SOH, the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current are first used to obtain the current pending value of the battery's equivalent ohmic internal resistance, and the number i of the current pending values ​​is accumulated.

[0059] When the accumulated number i of current values ​​to be processed is equal to the second preset threshold, that is, when the accumulated number of current values ​​to be processed reaches the second preset threshold, the current value of the equivalent ohmic internal resistance of the battery is calculated using the average value algorithm based on the current value to be processed. In this way, the calculated current value of the equivalent ohmic internal resistance of the battery is more accurate, which helps to improve the estimation accuracy of the battery's SOH.

[0060] After obtaining the current value of the equivalent ohmic internal resistance of the battery, i is updated to 0, the current pending value is cleared, and then the process returns to perform Kalman filtering on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to obtain the current pending value of the equivalent ohmic internal resistance of the battery, thereby calculating and updating the current value of the equivalent ohmic internal resistance of the battery.

[0061] When the accumulated number i of current values ​​to be processed does not reach the second preset threshold, the process returns to executing the battery detection to obtain the current value of the battery voltage and the current value of the battery current, thereby recalculating the current value of the battery SOC to calculate the current value to be processed of the equivalent ohmic internal resistance of the battery, and accumulating the number of current values ​​to be processed until the number of current values ​​to be processed reaches the second preset threshold.

[0062] In this way, the current value of the equivalent ohmic internal resistance of the battery is obtained, and the calculated value of the SOH of the battery can be obtained by performing Kalman filtering on the current value of the equivalent ohmic internal resistance of the battery.

[0063] To improve estimation accuracy, in an optional embodiment, an average value algorithm is called based on the current to-be-processed value of the equivalent ohmic internal resistance of the battery to determine the current value of the equivalent ohmic internal resistance of the battery, including:

[0064] Sorting the current to-be-processed values ​​of the equivalent ohmic internal resistance of the battery to obtain a sorting result;

[0065] Select the middle K values ​​from the sorting results;

[0066] The average value of the K values ​​is determined as the current value of the equivalent ohmic internal resistance of the battery.

[0067] Here, in order to calculate the current value of the ohmic internal resistance of the battery, the current pending values ​​of the equivalent ohmic internal resistance of the battery are first sorted to obtain a sorting result, wherein the current pending values ​​of the equivalent ohmic internal resistance of the battery can be sorted in order from large to small, or the current pending values ​​of the equivalent ohmic internal resistance of the battery can be sorted in order from small to large. The embodiment of the present application does not make specific limitations on this.

[0068] After obtaining the sorting results, the middle K values ​​can be selected from the sorting results. For example, when the number of values ​​to be processed in the sorting results is 5, K can be 3. When the number of values ​​to be processed in the sorting results is 4, K can be 2. After selecting the middle K values, the average value of the K values ​​is determined as the current value of the equivalent ohmic internal resistance of the battery.

[0069] In this way, by selecting the middle value and the average value for calculation, the current value of the equivalent ohmic internal resistance of the battery obtained is more accurate, which helps to improve the accuracy of the SOH of the battery.

[0070] In order to obtain a calculated value of the battery's SOH, in an optional embodiment, a Kalman filter is performed on the current value of the battery's equivalent ohmic internal resistance to obtain a calculated value of the battery's SOH, including:

[0071] Get preset parameters;

[0072] When the preset parameter is equal to the third preset threshold, the preset parameter is updated to the current value of the equivalent ohmic internal resistance of the battery, and the process returns to execute battery detection to obtain the current value of the battery voltage and the current value of the battery current;

[0073] When the preset parameter is not equal to the third preset threshold, Kalman filtering is performed on the current value of the equivalent ohmic internal resistance of the battery and the preset parameter to obtain a calculated value of the SOH of the battery.

[0074] Here, Kalman filtering is still used to pre-set preset parameters and a third preset threshold value, and determine whether the preset parameters are equal to the third preset threshold value. When equal, the preset parameters are updated to the current value of the equivalent ohmic internal resistance of the battery, and then return to execute the battery detection to obtain the current value of the battery voltage and the current value of the battery current, and recalculate the current value of the battery SOH. When not equal, Kalman filtering is performed on the equivalent ohmic internal resistance of the battery and the preset parameters to obtain the calculated value of the battery SOH.

[0075] Among them, the initial value of the above-mentioned preset parameter is usually the third preset threshold value. In this way, when the current value of the equivalent ohmic internal resistance of the battery is calculated for the first time, the preset parameter is simply updated, and then the battery detection is returned to recalculate the current value of the battery's SOH. When the current value of the equivalent ohmic internal resistance of the battery is calculated for the second time and thereafter, the calculated value of the battery's SOH is calculated again.

[0076] In this way, the calculated value of the battery's SOH is calculated using the current value of the battery's equivalent ohmic internal resistance calculated for the first time and the current value of the battery's equivalent ohmic internal resistance calculated each time, which is beneficial to improving the estimation accuracy of the battery's SOH.

[0077] In order to estimate the current value of the battery's SOH, in an optional embodiment, estimating the current value of the battery's SOH based on the calculated value of the battery's SOH includes:

[0078] Calculating the difference between the current value of the battery's SOH and the calculated value of the battery's SOH;

[0079] The current value of the battery's SOH is re-determined based on the relationship between the difference and the fourth preset threshold.

[0080] It can be understood that in order to improve the estimation accuracy, the difference between the current value of the battery's SOH and the calculated value of the battery's SOH is first calculated, and then the current value of the battery's SOH is re-determined using the relationship between the difference and the fourth preset threshold. Further, in order to re-determine the current value of the battery's SOH, in an optional embodiment, the current value of the battery's SOH is re-determined based on the relationship between the difference and the fourth preset threshold, including:

[0081] When the difference is less than a fourth preset threshold, updating the current value of the battery SOH to the calculated value of the battery SOH;

[0082] When the difference is greater than a fourth preset threshold, the current value of the SOH of the battery is updated to the difference between the current value of the battery and the fourth preset threshold.

[0083] It can be understood that when the difference is less than the fourth preset threshold, it means that the battery SOH changes within a certain range, and the reliability of the calculated value of the battery SOH is relatively high, so the calculated value of the battery SOH is directly used as the current value of the battery SOH. When the difference is greater than the fourth preset threshold, it means that the battery SOH changes greatly, and the reliability of the calculated value of the battery SOH is not high, so the difference between the calculated value of the battery SOH and the fourth preset threshold is used as the current value of the battery SOH.

[0084] In addition, when the difference is equal to the fourth preset threshold, the calculated value of the battery's SOH can be directly used as the current value of the battery's SOH, or the difference between the calculated value of the battery's SOH and the fourth preset threshold can be used as the current value of the battery's SOH. Here, the embodiment of the present application does not make specific limitations on this.

[0085] In this way, the influence of the estimation accuracy of the battery SOH caused by the error in the calculated value of the battery SOH is prevented, and the estimation accuracy of the battery SOH is further improved.

[0086] In addition, in order to improve the estimation accuracy, in an optional embodiment, the above method further includes: ending when the battery is charging and / or the current value of the battery SOC does not fall within a preset range.

[0087] Here, when the battery is charging, it ends, that is, the battery SOH is not estimated. When the current value of the battery SOC does not fall within the preset range, the battery SOH is not estimated. When the battery is charging and the current value of the battery SOC does not fall within the preset range, the battery SOH is not estimated. In other words, the unstable environment is excluded, and the battery SOH is estimated only when the environment is relatively stable, thereby improving the estimation accuracy of the battery SOH.

[0088] The following examples are used to illustrate the estimation method described in one or more of the above embodiments.

[0089] Figure 2 A flow chart of an example of an optional estimation method provided in an embodiment of the present application is shown as follows: Figure 2 As shown, the estimation method may include:

[0090] S201: Acquire voltage and current, and perform Kalman filtering on the detected voltage and current according to a preset strategy;

[0091] Because the Kalman filter method is a recursive calculation method, if the wrong voltage and current are input, it will have a significant impact on the entire life cycle of the operation. Therefore, before the collected voltage and current input into the Kalman filter, they are first input into a specific buffer mechanism. This buffer will filter out data that does not conform to the rules, and the data that conforms to the rules will be Kalman filtered.

[0092] Figure 3 A schematic diagram of a battery collection system provided in an embodiment of the present application is shown in FIG. Figure 3 As shown, when collecting the voltage and current of the battery, the acquisition system is used to collect the voltage of multiple battery cells and the current flowing through all the battery cells, and then the lowest voltage and current are selected. Then, the voltage and current input to the data cache are recorded as U0tn and I0tn respectively.

[0093] For example, after collecting U0tn and I0tn, when the voltage Utn is both 4, the following rules are used to obtain the battery voltage and current:

[0094] Rule 1: The current is negative when the battery is charging, and positive when the battery is discharging. The current is 0 when the battery is at rest. For example, when charging at 2A, the current Itn = -2, and when discharging at 2A, the current Itn = 2;

[0095] Rule 2: When Itn>0 at time tn, Ftn=1; when Itn<0 at time tn, Ftn=-1; when Itn=0 at time tn, Ftn=0;

[0096] Rule 3: When a symbol changes, the data at two moments before and two moments after the change are discarded and not output from the cache.

[0097] Table 1 is a specific operation example, where the output result X = not output from the cache, √ = output from the cache.

[0098] Table 1

[0099]

[0100] In addition, based on the battery voltage and current obtained above, the following strategy can be used to perform Kalman filtering on the obtained voltage and current:

[0101] Figure 4a A flow chart of another optional estimation method according to an embodiment of the present application is provided. Figure 4b A flow chart of an example of another optional estimation method provided in the embodiment of the present application is shown as follows: Figure 4aAs shown, during the battery discharge process, Kalman filter 1 is always running, that is, the battery's equivalent ohmic resistance, battery voltage and battery current are processed by Kalman filtering to obtain the battery's SOC, so that the battery's SOC is updated in real time; and an SOC segment is set during battery discharge. When the calculated SOC falls within the n%-m% segment, Kalman filter 2 is run, that is, the battery's SOC, battery voltage and battery current are processed by Kalman filtering to obtain the battery's equivalent ohmic internal resistance and battery SOH, so that the battery's SOH can be estimated; as shown Figure 4b As shown, during the battery charging process, Kalman filter 1 is always running to update the SOC in real time; during the battery charging process, Kalman filter 2 is stopped.

[0102] That is to say, when the battery is discharging, the battery's SOH is estimated only when the SOC falls within the n%-m% segment. When it does not fall within the n%-m% segment or when the battery is charging, the battery's SOH is not estimated. n%-m% is equivalent to the above-mentioned preset range interval.

[0103] S202: Is a valid Rn obtained? If yes, execute S203; if no, execute S201;

[0104] The above-mentioned S101 is used to collect data and process the data. Since the equivalent ohmic internal resistance and the battery are obtained only when the SOC falls within the n%-m% range, the SOH estimation can be determined by whether the equivalent ohmic internal resistance of the battery is obtained, that is, whether a valid Rn is obtained; wherein Rn is equivalent to the current pending value of the above-mentioned equivalent ohmic internal resistance.

[0105] If there is a valid Rn, execute S203; otherwise, execute S201 to re-acquire the battery voltage and current.

[0106] S203: Record Rn, and add 1 to the valid number C;

[0107] S204: Determine whether C>L is true. If so, execute S205; if not, execute S201;

[0108] Here, the number of valid Rn obtained is accumulated. Only when the accumulated number of Rn is greater than the set number L (for example, 10), S205 is executed. Otherwise, the process returns to S201 to re-acquire the battery voltage and current to obtain L Rn; N is equivalent to the above-mentioned second preset threshold.

[0109] S205: Sort the L times Rn by size, and take the average value R1 of the middle F values, C=0;

[0110] When L Rn are obtained, sort the L times Rn by size, take the average value R1 of the middle F values, use R1 to estimate the SOH of the battery, and clear L; where L is equivalent to the number of to-be-processed values ​​of the above-mentioned equivalent ohmic internal resistance.

[0111] S206: Determine whether Rinit=0 holds true. If so, execute S207; if not, execute S208.

[0112] S207: Rinit==R1; execute S201;

[0113] S208: SOH1 == (2Rinit - R1) / Rinit; execute S209;

[0114] After obtaining R1, when Rinit is equal to 0, the value of R1 is assigned to Rinit; when Rinit is not equal to 0, the value obtained by (2Rinit-R1) / Rinit is assigned to SOH1; wherein Rinit is equivalent to the above-mentioned preset parameter, 0 is equivalent to the above-mentioned third preset threshold, and SOH1 is equivalent to the calculated value of the SOH of the above-mentioned battery.

[0115] S209: Determine whether SOH1>SOHnow is true. If so, execute S210; if not, execute S211;

[0116] S210: SOHnow is not updated; return to execute S201;

[0117] S211: Determine whether (SOHnow - SOH1) > sohmax. If so, execute S212; if not, execute S213.

[0118] S212: SOHnow==SOHnow-sohmax;

[0119] S213: SOHnow==SOH1.

[0120] Here, SOHnow is equivalent to the current value of the SOH of the battery, sohmax is equivalent to the fourth preset threshold, and in practical applications, the initial value of SOHnow is 0, and SOHnow can be 10%.

[0121] In this example, during the use of the battery, the above preset strategy is run and two Kalman filters are run alternately to achieve the goal of accurately calculating the battery life.

[0122] The estimation method provided in the embodiment of the present application includes: detecting the battery to obtain the current value of the battery voltage and the current value of the battery current, performing Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the battery voltage and the current value of the battery current to obtain the current value of the SOC of the battery; when the battery is discharged and the current value of the SOC of the battery falls within a preset range, performing Kalman filtering on the current value of the SOC of the battery, the current value of the battery voltage and the current value of the battery current to estimate the current value of the SOH of the battery; that is, in the embodiment of the present application, the current value of the battery voltage, the current value of the battery current and the current value of the equivalent ohmic internal resistance of the battery obtained by battery detection are Kalman filtered. Kalman filtering is performed on the current value of the battery's SOC to obtain the current value of the battery's SOC, and only when the battery is discharged and the current value of the battery's SOC falls within a preset range, the current value of the battery's SOC, the current value of the detected battery voltage, and the current value of the current are processed by Kalman filtering. Compared with directly performing Kalman filtering on the current value of the battery's SOC, the current value of the detected battery voltage, and the current value of the current, the estimated current value of the battery's SOH is more accurate. In this way, by judging the battery state and the current value of the battery's SOC, and using Kalman filtering to estimate the current value of the battery's SOH when the battery is discharged and the current value of the battery's SOC falls within a preset range, the battery life can be estimated more accurately.

[0123] Based on the same inventive concept, an embodiment of the present application provides an estimation device, Figure 5 This is a schematic diagram of an optional estimation device provided in an embodiment of the present application, referring to Figure 5 As shown, it includes: a detection module 51, a filtering module 52 and an estimation module 53; wherein,

[0124] A detection module 51 is used to detect the battery and obtain the current value of the battery voltage and the current value of the battery current;

[0125] a filtering module 52 for performing Kalman filtering on the acquired current value of the equivalent ohmic internal resistance of the battery, the current value of the battery voltage, and the current value of the battery current to obtain a current value of the battery SOC;

[0126] The estimation module 53 is used to perform Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current when the battery is discharged and the current value of the battery SOC falls within a preset range, so as to estimate the current value of the battery SOH.

[0127] In other embodiments of the present application, the detection module 51 is specifically configured to:

[0128] Detect the battery to obtain the current voltage detection value and the current current detection value of the battery;

[0129] Obtain the first M voltage detection values ​​of the battery, the last N voltage detection values ​​of the battery, the first M current detection values ​​of the battery, and the last N current detection values ​​of the battery;

[0130] Based on the current voltage detection value, determine the number of voltage detection values ​​that have changed between the previous M voltage detection values ​​and the next N voltage detection values;

[0131] Based on the current detection value, determine the number of current detection values ​​that have changed between the previous M current detection values ​​and the next N current detection values;

[0132] When the sum of the number of changed voltage detection values ​​and the number of changed current detection values ​​is less than a first preset threshold, the current voltage detection value is determined as the current value of the battery voltage, and the current current detection value is determined as the current value of the battery current.

[0133] In other embodiments of the present application, the first preset threshold is 0.

[0134] In other embodiments of the present application, the estimation module 53 is specifically configured to:

[0135] When the battery is discharged and the current value of the battery's SOC falls within a preset range, a Kalman filter is performed on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to obtain a calculated value of the battery's SOH;

[0136] When the calculated value of the battery's SOH is less than the current value of the battery's SOH, the current value of the battery's SOH is estimated based on the calculated value of the battery's SOH.

[0137] In other embodiments of the present application, the estimation module 53 performs Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain a calculated value of the battery SOH, including:

[0138] Perform Kalman filtering on the current value of the battery's SOC, the current value of the battery's voltage, and the current value of the battery's current to-be-processed equivalent ohmic internal resistance to obtain the current value to-be-processed of the battery's equivalent ohmic internal resistance; update i to i+1; where i is the number of the current values ​​to-be-processed of the battery's equivalent ohmic internal resistance, and the initial value of i is 0;

[0139] When i is equal to a second preset threshold, based on the current pending value of the equivalent ohmic internal resistance of the battery, an average value algorithm is called to determine the current value of the equivalent ohmic internal resistance of the battery, i is updated to 0, the current pending value of the equivalent ohmic internal resistance of the battery is cleared, and the process returns to perform Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain the current pending value of the equivalent ohmic internal resistance of the battery;

[0140] When i is less than a second preset threshold, returning to execute battery detection to obtain a current value of the battery voltage and a current value of the battery current;

[0141] The current value of the equivalent ohmic internal resistance of the battery is processed by Kalman filtering to obtain the calculated value of the SOH of the battery.

[0142] In other embodiments of the present application, the estimation module 53 calls an average value algorithm based on the current to-be-processed value of the equivalent ohmic internal resistance of the battery to determine the current value of the equivalent ohmic internal resistance of the battery, including:

[0143] Sorting the current to-be-processed values ​​of the equivalent ohmic internal resistance of the battery to obtain a sorting result;

[0144] Select the middle K values ​​from the sorting results;

[0145] The average value of the K values ​​is determined as the current value of the equivalent ohmic internal resistance of the battery.

[0146] In other embodiments of the present application, the estimation module 53 performs Kalman filtering on the current value of the equivalent ohmic internal resistance of the battery to obtain a calculated value of the battery's SOH, including:

[0147] Get preset parameters;

[0148] When the preset parameter is equal to the third preset threshold, the preset parameter is updated to the current value of the equivalent ohmic internal resistance of the battery, and the process returns to execute battery detection to obtain the current value of the battery voltage and the current value of the battery current;

[0149] When the preset parameter is not equal to the third preset threshold, Kalman filtering is performed on the current value of the equivalent ohmic internal resistance of the battery and the preset parameter to obtain a calculated value of the SOH of the battery.

[0150] In other embodiments of the present application, the estimation module 53 estimates the current value of the battery SOH based on the calculated value of the battery SOH, including:

[0151] Calculating the difference between the current value of the battery's SOH and the calculated value of the battery's SOH;

[0152] The current value of the battery's SOH is re-determined based on the relationship between the difference and the fourth preset threshold.

[0153] In other embodiments of the present application, the estimation module 53 re-determines the current value of the battery SOH based on the relationship between the difference and the fourth preset threshold, including:

[0154] When the difference is less than a fourth preset threshold, updating the current value of the battery SOH to the calculated value of the battery SOH;

[0155] When the difference is greater than a fourth preset threshold, the current value of the SOH of the battery is updated to the difference between the current value of the battery and the fourth preset threshold.

[0156] In other embodiments of the present application, the device is also used for:

[0157] When the battery is charged and / or the current value of the battery SOC does not fall within the preset range, the process ends.

[0158] In practical applications, the above-mentioned detection module 51, filtering module 52 and estimation module 53 can be implemented by a processor located on the estimation device, specifically a central processing unit (CPU), a microprocessor (MPU), a digital signal processor (DSP) or a field programmable gate array (FPGA).

[0159] Figure 6 A schematic diagram of the structure of an optional electronic device provided in an embodiment of the present application is shown in FIG. Figure 6 As shown, an embodiment of the present application provides an electronic device 600, including:

[0160] A processor 61 and a storage medium 62 storing instructions executable by the processor 61, wherein the storage medium 62 relies on the processor 61 to perform operations via a communication bus 63. When the instructions are executed by the processor 61, the estimation method described in one or more of the above embodiments is executed.

[0161] It should be noted that in actual application, the various components in the terminal are coupled together through the communication bus 63. It is understood that the communication bus 63 is used to realize the connection and communication between these components. In addition to the data bus, the communication bus 63 also includes a power bus, a control bus and a status signal bus. However, for the sake of clarity, Figure 6 Various buses are labeled as communication buses 63.

[0162] An embodiment of the present application provides a storage medium storing one or more programs. The one or more programs can be executed by one or more processors to implement the estimation method provided in the embodiment of the present application.

[0163] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, systems, or computer program products. Therefore, the present application may adopt the form of hardware embodiments, software embodiments, or embodiments combining software and hardware. Furthermore, the present application may adopt the form of a computer program product implemented on one or more computer-usable storage media (including but not limited to magnetic disk storage and optical storage, etc.) containing computer-usable program code.

[0164] The present application is described with reference to the flowcharts and / or block diagrams of the methods, devices (systems), and computer program products according to the embodiments of the present application. It should be understood that each process and / or box in the flowchart and / or block diagram, as well as the combination of the processes and / or boxes in the flowchart and / or block diagram, can be implemented by computer program instructions. These computer program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device generate instructions for implementing the steps in the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A device that provides the functions specified in a block or multiple blocks.

[0165] These computer program instructions may also be stored in a computer readable memory that can direct a computer or other programmable data processing device to work in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture comprising an instruction device, which implements the process Figure 1 a process or multiple processes and / or boxes Figure 1 The function specified in one or more boxes.

[0166] These computer program instructions can also be loaded onto a computer or other programmable data processing device so that a series of operational steps are executed on the computer or other programmable device to produce a computer-implemented process, thereby providing the instructions executed on the computer or other programmable device for implementing the process. Figure 1 a process or multiple processes and / or boxes Figure 1 A step that specifies a function in one or more boxes.

[0167] The above description is merely a preferred embodiment of the present application and is not intended to limit the scope of protection of the present application.

Claims

1. An estimation method, characterized in that include: Detecting the battery to obtain a current value of the battery voltage and a current value of the battery current; Performing Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain a current value of the SOC of the battery; When the battery is discharged and a current value of the battery SOC falls within a preset range, performing Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to estimate a current value of the battery SOH; The performing Kalman filtering on the current value of the SOC of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to estimate the current value of the SOH of the battery includes: performing Kalman filtering on a current value of the battery SOC, a current value of the battery voltage, and a current value of the battery current to update and obtain a current value of the equivalent ohmic internal resistance of the battery; A current value of the SOH of the battery is determined according to a current value of the equivalent ohmic internal resistance of the battery.

2. The method according to claim 1, characterized in that The detecting of the battery to obtain a current value of the battery voltage and a current value of the battery current includes: Detecting the battery to obtain a current voltage detection value and a current current detection value of the battery; Obtaining the first M voltage detection values ​​of the battery, the last N voltage detection values ​​of the battery, the first M current detection values ​​of the battery, and the last N current detection values ​​of the battery; Based on the current voltage detection value, determine the number of voltage detection values ​​that have changed among the first M voltage detection values ​​and the last N voltage detection values; Based on the current detection value, determine the number of current detection values ​​that have changed among the first M current detection values ​​and the last N current detection values; When the sum of the number of the changed voltage detection values ​​and the number of the changed current detection values ​​is less than a first preset threshold, the current voltage detection value is determined as the current value of the battery voltage, and the current current detection value is determined as the current value of the battery current.

3. The method according to claim 2, characterized in that The first preset threshold is 0.

4. The method according to claim 1, wherein When the battery is discharged and a current value of the SOC of the battery falls within a preset range, Kalman filtering is performed on the current value of the SOC of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to estimate a current value of the SOH of the battery, including: When the battery is discharged and a current value of the battery SOC falls within a preset range, performing Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain a calculated value of the battery SOH; When the calculated value of the battery SOH is less than the current value of the battery SOH, the current value of the battery SOH is estimated based on the calculated value of the battery SOH.

5. The method according to claim 4, characterized in that The performing Kalman filtering on the current value of the SOC of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain a calculated value of the SOH of the battery includes: Performing Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to obtain a current value to be processed of the equivalent ohmic internal resistance of the battery; updating i to i+1; where i is the number of current values ​​to be processed of the equivalent ohmic internal resistance of the battery, and the initial value of i is 0; When i is equal to a second preset threshold, calling an average value algorithm according to the current pending value of the equivalent ohmic internal resistance of the battery to determine the current value of the equivalent ohmic internal resistance of the battery, updating i to 0, clearing the current pending value of the equivalent ohmic internal resistance of the battery, and returning to execute the Kalman filtering process on the current value of the SOC of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain the current pending value of the equivalent ohmic internal resistance of the battery; When i is less than a second preset threshold, returning to executing the battery detection to obtain a current value of the battery voltage and a current value of the battery current; Kalman filtering is performed on the current value of the equivalent ohmic internal resistance of the battery to obtain a calculated value of the SOH of the battery.

6. The method according to claim 5, characterized in that The step of calling an average value algorithm based on the current to-be-processed value of the equivalent ohmic internal resistance of the battery to determine the current value of the equivalent ohmic internal resistance of the battery includes: Sorting the current to-be-processed values ​​of the equivalent ohmic internal resistance of the battery to obtain a sorting result; Selecting middle K values ​​from the sorting results; The average value of the K values ​​is determined as the current value of the equivalent ohmic internal resistance of the battery.

7. The method according to claim 5, characterized in that The performing Kalman filtering on the current value of the equivalent ohmic internal resistance of the battery to obtain a calculated value of the SOH of the battery includes: Get preset parameters; When the preset parameter is equal to a third preset threshold, updating the preset parameter to a current value of the equivalent ohmic internal resistance of the battery, returning to executing the battery detection to obtain a current value of the battery voltage and a current value of the battery current; When the preset parameter is not equal to the third preset threshold, Kalman filtering is performed on the current value of the equivalent ohmic internal resistance of the battery and the preset parameter to obtain a calculated value of the SOH of the battery.

8. The method according to claim 4, characterized in that The estimating a current value of the SOH of the battery according to the calculated value of the SOH of the battery includes: calculating a difference between a current value of the SOH of the battery and a calculated value of the SOH of the battery; The current value of the SOH of the battery is re-determined based on the relationship between the difference and a fourth preset threshold.

9. The method according to claim 8, characterized in that The re-determining the current value of the SOH of the battery according to the relationship between the difference and a fourth preset threshold value includes: When the difference is less than the fourth preset threshold, updating the current value of the battery SOH to the calculated value of the battery SOH; When the difference is greater than the fourth preset threshold, the current value of the SOH of the battery is updated to the difference between the current value of the battery and the fourth preset threshold.

10. The method according to claim 1, characterized in that The method further comprises: When the battery is charged and / or the current value of the SOC of the battery does not fall within the preset range, the process ends.

11. An estimation device, characterized in that include: a detection module, configured to detect the battery and obtain a current value of the battery voltage and a current value of the battery current; a filtering module, configured to perform Kalman filtering on the obtained current value of the equivalent ohmic internal resistance of the battery, the current value of the voltage of the battery, and the current value of the current of the battery to obtain a current value of the SOC of the battery; an estimation module, configured to, when the battery is discharged and a current value of the battery SOC falls within a preset range, perform Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to estimate a current value of the battery SOH; The estimation module performs Kalman filtering on the current value of the battery SOC, the current value of the battery voltage, and the current value of the battery current to estimate the current value of the battery SOH, including: performing Kalman filtering on a current value of the battery SOC, a current value of the battery voltage, and a current value of the battery current to update and obtain a current value of the equivalent ohmic internal resistance of the battery; A current value of the SOH of the battery is determined according to a current value of the equivalent ohmic internal resistance of the battery.

12. An electronic device, characterized in that: include: A processor and a storage medium storing instructions executable by the processor, wherein the storage medium relies on the processor to perform operations via a communication bus, and when the instructions are executed by the processor, the estimation method described in any one of claims 1 to 10 is executed.

13. A storage medium, characterized in that: The storage medium stores one or more programs, and the one or more programs can be executed by one or more processors to implement the estimation method according to any one of claims 1 to 10.

Images