CN108248427B - Method for dynamically correcting SOC error - Google Patents
Method for dynamically correcting SOC error Download PDFInfo
- Publication number
- CN108248427B CN108248427B CN201810036405.9A CN201810036405A CN108248427B CN 108248427 B CN108248427 B CN 108248427B CN 201810036405 A CN201810036405 A CN 201810036405A CN 108248427 B CN108248427 B CN 108248427B
- Authority
- CN
- China
- Prior art keywords
- battery
- soc
- error
- current
- management system
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B60—VEHICLES IN GENERAL
- B60L—PROPULSION OF ELECTRICALLY-PROPELLED VEHICLES; SUPPLYING ELECTRIC POWER FOR AUXILIARY EQUIPMENT OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRODYNAMIC BRAKE SYSTEMS FOR VEHICLES IN GENERAL; MAGNETIC SUSPENSION OR LEVITATION FOR VEHICLES; MONITORING OPERATING VARIABLES OF ELECTRICALLY-PROPELLED VEHICLES; ELECTRIC SAFETY DEVICES FOR ELECTRICALLY-PROPELLED VEHICLES
- B60L58/00—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles
- B60L58/10—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries
- B60L58/12—Methods or circuit arrangements for monitoring or controlling batteries or fuel cells, specially adapted for electric vehicles for monitoring or controlling batteries responding to state of charge [SoC]
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02T—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION
- Y02T10/00—Road transport of goods or passengers
- Y02T10/60—Other road transportation technologies with climate change mitigation effect
- Y02T10/70—Energy storage systems for electromobility, e.g. batteries
Landscapes
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Sustainable Development (AREA)
- Sustainable Energy (AREA)
- Power Engineering (AREA)
- Transportation (AREA)
- Mechanical Engineering (AREA)
- Secondary Cells (AREA)
Abstract
The invention relates to a method for dynamically correcting SOC errors, which is used for correcting SOC errors (including range errors and current peak errors) of a battery system acquired by a battery management system, and comprises the following steps: (1) estimating a range error during charging of the battery system; (2) estimating a current peak error during operation of the battery system; (3) and correcting the SOC of the battery system acquired by the obtained range error and current peak error. The method for dynamically correcting the SOC error can prevent the jump of the SOC in the working process of the system, estimate the SOC error value caused by the frequent change of the bus current in the working process of the battery system, and dynamically correct the SOC error caused by the SOC calculation by adopting an ampere-hour integration method, so that the calculation result of the SOC can be more accurate, and the method does not need longer standing time as the method for correcting the SOC by adopting an open-circuit voltage method, and is suitable for the environment of uninterrupted working.
Description
Technical Field
The invention relates to the field of battery management, in particular to a battery electric quantity detection technology, and specifically relates to a method for dynamically correcting SOC errors.
Background
At present, the problem Of accurately calculating the remaining battery capacity (SOC) through a Battery Management System (BMS) is the difficulty Of the whole industry, a certain SOC jump Of a battery system often occurs at the end Of a discharge period, and the SOC jump amplitude is increased under the conditions that the battery system has a large range and the use condition changes violently.
During the charging phase, the battery management system usually employs a charging phase with a segmented constant current to improve the charging efficiency of the battery system. The method for estimating the remaining capacity of the battery system, which is usually adopted by the battery management system, comprises the steps of estimating the SOC of the battery system by adopting an ampere-hour integration method, wherein when the SOC is estimated by adopting the ampere-hour integration method, the estimation result is mainly influenced by the following factors:
(1) the extreme variation of the battery system versus the available capacity;
(2) change in current magnitude versus available capacity of the battery;
(3) the detection system collects the frequency of the current signal.
As can be seen from the above, when the ampere-hour integration method is used to estimate the SOC, it is impossible to measure the decrease in the available capacity due to the extreme difference of the battery system, and the current data collected by the battery management system during SOC estimation is usually discrete, but actually the change in the bus current is continuous, so it is inevitable that the collected data and the actual data have a certain deviation when the current data is collected, and since the battery capacities corresponding to different currents are also different, an error occurs in the SOC calculated by using only the ampere-hour integration method when the bus current frequently changes.
In the prior art, a more common method is to calculate the SOC value of the battery system by using an ampere-hour integration method when the battery system is dynamically changed, and correct the SOC value by using an open-circuit voltage look-up table method after the battery system is sufficiently stationary, but the open-circuit voltage look-up table method requires the battery system to be stationary for a long time to ensure the accuracy of the battery system, so if the battery system is in a working process and cannot be stationary for a long time, the SOC calculation error generated by the ampere-hour integration method cannot be normally corrected.
In the running process of a vehicle, due to the difference of the working condition of the vehicle and the weather environment, the current fluctuation of the vehicle load is large, errors are inevitably generated in the SOC result calculated by an ampere-hour integration method, although the SOC error accumulated in multiple charging and discharging cycles can be corrected by an open-circuit voltage method and a charging stage after fully standing, the errors generated in a complete discharging process still cause the errors in the calculation of the SOC of a battery system.
Disclosure of Invention
The object of the present invention is to overcome the above mentioned drawbacks of the prior art and to provide a method for dynamically correcting SOC errors that allows estimation of SOC errors due to extreme differences during charging.
In order to achieve the above object, the method for dynamically correcting SOC error of the present invention specifically includes:
the method for dynamically correcting the SOC error is mainly characterized in that a battery management system for an electric vehicle dynamically corrects the error when acquiring the SOC of a battery system, wherein the SOC error comprises an extreme error and a current peak value error, and the method comprises the following steps:
(1) the battery management system estimates a range error in the charging process of the battery system;
(2) the battery management system estimates the current peak value error in the working process of the battery system;
(3) and the battery management system corrects the SOC of the battery system acquired by the battery management system according to the acquired range error and the current peak error.
Preferably, the battery management system obtains the SOC of the battery system by an ampere-hour integration method, and the battery management system controls the battery system to charge by adopting a sectional constant current charging stage in the charging process of the battery system.
Preferably, the charging phase of the battery system includes a large current constant current charging phase and a small current constant current charging phase, and the extreme value error is obtained in the step (1) through the following steps:
(1.1) the battery management system selects at least two battery monomers in the battery system and acquires the voltage values of the selected battery monomers;
(1.2) the battery management system sorts the selected battery monomers according to the voltage values of the selected battery monomers;
(1.3) the battery management system acquires the voltage difference between any two adjacent battery monomers after sequencing, and divides the voltage difference larger than the threshold value into a large current group and divides the voltage difference smaller than the threshold value into a small current group through a preset threshold value;
(1.4) the battery management system obtains a large-current charging extreme difference error according to the voltage difference of the large-current set and the voltage value of the single battery forming the voltage difference in the large-current constant-current charging stage; the battery management system acquires a low-current charging pole difference error according to the voltage difference of the low-current group and the voltage value of the battery monomer forming the voltage difference in the low-current constant-current charging stage;
and (1.5) the battery management system adds the large-current charging range error and the small-current charging range error to obtain a range error.
Preferably, the step (1.4) of obtaining the range error according to the voltage difference and the voltage value of the battery cell constituting the voltage difference includes:
the battery management system acquires the electric quantity required by the battery monomer with a lower voltage value in the battery monomers forming the voltage difference to increase the voltage difference, divides the electric quantity by the rated capacity of the battery monomer to acquire a single group of pole difference errors, and accumulates all the single group of pole difference errors after acquiring the single group of pole difference errors of two adjacent groups of battery monomers to acquire a large-current pole difference error or a small-current pole difference error.
More preferably, the step (1.1) further comprises the following steps:
(1.0) the battery management system acquires the terminal voltage of each battery monomer in the battery system, and judges whether the change of the terminal voltage of each battery monomer enters a stable state, if so, the step (1.1) is carried out, and if not, the step continues to judge whether the voltage change of the current battery system enters the stable state.
More preferably, the determining whether the change of the terminal voltage of each battery cell enters the steady state specifically includes:
the battery management system judges whether the terminal voltage of the battery cell acquired by the battery management system is in the rising channel.
More preferably, the step (2) comprises the following steps:
(2.1) the battery management system acquires the number and intensity of positive peaks of bus current and the number and intensity of current feedback of the battery system in a preset time;
and (2.2) inquiring a current peak value SOC error table by the battery management system according to the number and intensity of the positive peak and the number and intensity of current feedback, and acquiring current peak value errors corresponding to the positive peak and the current feedback.
More preferably, the step (3) comprises the following steps:
(3.1) the battery management system acquires a battery cell with the highest voltage value in the battery system, and acquires the SOC after correcting the pole error according to the acquired pole error;
and (3.2) the battery management system corrects the current peak error of the SOC after the pole error is corrected according to the acquired current peak error.
Preferably, the step of acquiring the SOC after correcting the pole error by the battery management system is:
(3.1.1) the battery management system acquires the SOC _ H of the battery cell with the highest voltage value, and subtracts the pole difference error from the SOC _ H of the battery cell with the highest voltage value to acquire the SOC _ L of the battery cell with the lowest voltage value;
and (3.1.2) weighting the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value by the battery management system to obtain the SOC after the pole error is corrected.
Preferably, in the step (3.1.2), the battery management system weights the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value according to the following formula to obtain the SOC after correcting the pole error:
SOC＝α×SOC_H+β×SOC_L；
wherein α and β are weighted values, α + β is 1, and α is SOC _ H/100.
By adopting the method for dynamically correcting the SOC error, the SOC calculation accuracy of the battery management system is improved, the SOC can be prevented from jumping in the system working process, and the SOC error value caused by frequent change of bus current can be estimated in the battery system working process. The SOC error value caused by SOC estimation by adopting an ampere-hour integration method can be dynamically corrected, so that the calculation result of the SOC can be more accurate. Meanwhile, the longer standing time required by correcting the SOC by the open-circuit voltage is avoided, so that the battery management system adopting the method disclosed by the invention can be suitable for an environment with uninterrupted work.
Drawings
Fig. 1 is a flowchart of calculation of SOC error based on battery system pole error.
Fig. 2 is a flowchart of a calculation for obtaining SOC correction errors based on the number of times current spikes and current feedback occur in the bus current.
Detailed Description
In order to clearly understand the technical contents of the present invention, the following examples are given in detail.
The method for dynamically correcting the SOC error is used for dynamically correcting the error when a battery management system of an electric vehicle acquires the SOC of a battery system, wherein the SOC error comprises an extreme error and a current peak value error, and the method comprises the following steps of:
(1) the battery management system estimates a range error in the charging process of the battery system;
(2) the battery management system estimates the current peak value error in the working process of the battery system;
(3) and the battery management system corrects the SOC of the battery system acquired by the battery management system according to the acquired range error and the current peak error.
In a preferred embodiment, the battery management system obtains the SOC of the battery system by an ampere-hour integration method, and the battery management system controls the battery system to charge in a charging process of the battery system by using a sectional constant current charging stage.
In a preferred embodiment, the charging phases of the battery system include a large current constant current charging phase and a small current constant current charging phase, and the step (1) obtains the extreme value error by:
(1.1) the battery management system selects at least two battery monomers in the battery system and acquires the voltage values of the selected battery monomers;
(1.2) the battery management system sorts the selected battery monomers according to the voltage values of the selected battery monomers;
(1.3) the battery management system acquires the voltage difference between any two adjacent battery monomers after sequencing, and divides the voltage difference larger than the threshold value into a large current group and divides the voltage difference smaller than the threshold value into a small current group through a preset threshold value;
(1.4) the battery management system obtains a large-current charging extreme difference error according to the voltage difference of the large-current set and the voltage value of the single battery forming the voltage difference in the large-current constant-current charging stage; the battery management system acquires a low-current charging pole difference error according to the voltage difference of the low-current group and the voltage value of the battery monomer forming the voltage difference in the low-current constant-current charging stage;
and (1.5) the battery management system adds the large-current charging range error and the small-current charging range error to obtain a range error.
In a more preferred embodiment, the step (1.4) of obtaining the range error according to the voltage difference and the voltage value of the battery cell constituting the voltage difference includes:
the battery management system acquires the electric quantity required by the battery monomer with a lower voltage value in the battery monomers forming the voltage difference to increase the voltage difference, divides the electric quantity by the rated capacity of the battery monomer to acquire a single group of pole difference errors, and accumulates all the single group of pole difference errors after acquiring the single group of pole difference errors of two adjacent groups of battery monomers to acquire a large-current pole difference error or a small-current pole difference error.
In a more preferred embodiment, said step (1.1) is preceded by the steps of:
(1.0) the battery management system acquires the terminal voltage of each battery monomer in the battery system, and judges whether the change of the terminal voltage of each battery monomer enters a stable state, if so, the step (1.1) is carried out, and if not, the step continues to judge whether the voltage change of the current battery system enters the stable state. In a specific embodiment, in the charging phase, no matter in the large current constant current phase or the small current constant current phase, the SOC is obtained through the battery management system when the terminal voltage of the battery cell in the battery system changes in a steady state.
In a more preferred embodiment, the determining whether the terminal voltage of each battery cell changes into the steady state specifically includes:
the battery management system judges whether the terminal voltage of the battery cell acquired by the battery management system is in the rising channel.
In a more preferred embodiment, the step (2) comprises the following steps:
(2.1) the battery management system acquires the number and intensity of positive peaks of bus current and the number and intensity of current feedback of the battery system in a preset time;
and (2.2) inquiring a current peak value SOC error table by the battery management system according to the number and intensity of the positive peak and the number and intensity of current feedback, and acquiring current peak value errors corresponding to the positive peak and the current feedback.
In a more preferred embodiment, the step (3) comprises the following steps:
(3.1) the battery management system acquires a battery cell with the highest voltage value in the battery system, and acquires the SOC after correcting the pole error according to the acquired pole error;
and (3.2) the battery management system corrects the current peak error of the SOC after the pole error is corrected according to the acquired current peak error.
In a more preferred embodiment, the step of acquiring the SOC after correcting the pole error by the battery management system is:
(3.1.1) the battery management system acquires the SOC _ H of the battery cell with the highest voltage value, and subtracts the pole difference error from the SOC _ H of the battery cell with the highest voltage value to acquire the SOC _ L of the battery cell with the lowest voltage value;
and (3.1.2) weighting the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value by the battery management system to obtain the SOC after the pole error is corrected.
In a more preferred embodiment, the battery management system in step (3.1.2) weights the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value according to the following formula to obtain the SOC after correcting the pole error:
SOC＝α×SOC_H+β×SOC_L；
wherein α and β are weighted values, α + β is 1, and α is SOC _ H/100.
Referring to fig. 2, in an embodiment, the battery management system may further correct the current peak error, specifically:
the battery management system judges whether the lower limit of the voltage of the battery monomer is reached or the battery is fully stood, if the lower limit of the voltage of the battery monomer is reached, the battery management system judges whether the SOC for correcting the current peak value error is equal to 0 or not, and if the SOC is equal to 0, the current peak value error does not need to be further corrected; if not, further correcting the current peak value error according to the SOC for correcting the current peak value error; if the single battery is fully static, the SOC of the single battery is obtained through an open-circuit voltage method, the SOC is compared with the SOC subjected to overcurrent peak value error correction, if the SOC is equal to the SOC subjected to overcurrent peak value error correction, further correction of the SOC subjected to current peak value error correction is not needed, and if a difference exists between the SOC and the SOC, the battery management system further corrects the current peak value error according to the difference.
The SOC corrected for the current peak error in step (3.2) is further corrected according to the above-described correction procedure. In a specific embodiment, the "further correction" is that the battery management system updates a value stored in a table of SOC errors corresponding to current peak values in the battery management system, and further corrects and updates the SOC error corresponding to a certain current peak value according to "SOC corrected for current peak value error" corresponding to the lower voltage limit of the battery cell or "difference" when the battery cell has been sufficiently left still.
In a specific embodiment, in the charging stage of the battery system, the battery management system generally controls the charging of the battery by using a sectional constant current charging stage to improve the charging efficiency of the battery system, so that the battery management system of the present invention obtains different range errors based on different charging stages, and the calculation method for the range errors is as follows:
(1) the voltage values of (at least two) battery cells in the battery system are selected and saved as the starting points of the calculation. And acquiring the voltage value of each selected battery cell. For example, the battery cells with local highest voltage values and local lowest voltage values given by each acquisition board in the battery management system are adopted, and the voltage values of the battery cells and the local highest voltage values are obtained as data for calculating error values, so that the range of the battery system is decomposed into voltage differences among the battery cells, the overall calculation time is shortened, and the calculation error caused by the rise of terminal voltage due to battery polarization is reduced.
(2) Sorting each battery monomer according to the voltage value of the selected battery monomer, determining the voltage difference between every two adjacent voltage values, dividing the voltage difference into a large current group and a small current group through a preset threshold, if the voltage difference is small, calculating only in a small current constant current charging stage, and if the voltage difference is large, calculating only in the large current constant current charging stage. The reason for adopting this mode is that the time length of the low current constant current charging stage is generally short, and for the situation that the voltage difference is relatively large, the time required by the error calculated by the low current is relatively long, and the situation that the calculation is not completed easily occurs, while the polarization phenomenon generated by the battery in the same time in the high current constant current charging stage is more obvious than that of the low current, so the terminal voltage rising speed is very fast, and the method is not suitable for the situation that the voltage difference between the battery monomers is relatively small.
According to the experimental data of the ternary lithium battery system, under the similar charging starting condition, when the differential pressure of two single batteries exceeds 35mv, the error between the result calculated in the low-current constant-current charging stage and the result calculated in the high-current constant-current charging stage is within 5%. (error: 1-result of small current/result of large current). times.100%). Therefore, under the condition that the voltage difference of the two single batteries is larger, it is reasonable to calculate a part of range error values respectively in a large-current constant-current charging stage and a small-current constant-current charging stage. When the voltage difference of the single battery is small, the range error at the time of small current is calculated only in a small current constant current charging stage, when the voltage difference of the single battery is large, the range error at the time of large current is calculated only in a large current constant current charging stage, the range error at the time of small current and the range error at the time of large current are added, and a new range error delta SOC is obtained. The corresponding software flow diagram is shown in fig. 1.
In fig. 1, v1, v2, v3 … and vn indicate the voltage values of the battery cells, v1 ', v 2', v3 '… and vn' indicate the voltage values of the battery cells updated in real time, and t1, t2, t3, … and tn-1 indicate time. The steady state during charging refers to a period in which the voltage rises slowly. Fig. 1 shows that voltage comparison and judgment are required, and this step illustrates that only when all the current updated cell voltage values are greater than the value of the corresponding next voltage point, the time from vn to vn ' may be saved to obtain the corresponding electric quantity, and further obtain the corresponding range error, and add or between v1 ' > v2 and v2 ' > v3 … to indicate that the condition is that corresponding time counting can be performed as long as the condition is satisfied.
When the battery system finishes charging and enters a discharging state, the battery management system has three values of SOC, namely SOC _ H, SOC _ L and pole difference error delta SOC, the battery management system obtains the SOC _ H of the battery cell with the highest voltage value, the SOC of the battery cell with the highest voltage value is subtracted from the pole difference error delta SOC to obtain the SOC _ L of the battery cell with the lowest voltage value, and the battery management system weights the calculated SOC _ H and SOC _ L to obtain the SOC of the current battery system, so that the finally calculated SOC can more accurately reflect the electric quantity condition of the current battery system. The method specifically comprises the following steps:
SOC＝α×SOC_H+β×SOC_L；
where α and β are weights, the relationship between α and β is linear, and α + β is 1.
In a specific embodiment, α is obtained by the following formula:
α＝SOC_H/100。
in the discharging stage, a large current will cause a decrease in the available capacity of the battery, and meanwhile, due to the characteristics of the current sensor, when a forward current spike occurs, a certain deviation exists between the peak value of the measured current and the actual current peak value, and the measured value is usually smaller than the actual value. Therefore, during the running of the vehicle, the positive current spike and the current feedback occurring in the bus current also cause an error. The more times they occur in the same time, the more the deviation of the SOC that needs to be corrected, and the amount of the specific deviation needs to be determined in accordance with both their intensity and number of times. Therefore, the battery management system obtains current peak value errors corresponding to the forward current peak value and the current feedback frequency and intensity by looking up a table according to the forward current peak value and the current feedback frequency and intensity in the bus current of the battery system counted in a period of time, and updates the SOC to be output to a driver according to the current peak value errors, so that the SOC is accurately estimated when the bus current changes frequently.
The current peak error table is obtained through experimental tests, and the relation between different current peaks and SOC errors is determined under different working currents, so that the current peak error table is obtained.
By adopting the method for dynamically correcting the SOC error, the SOC calculation accuracy of the battery management system is improved, the SOC can be prevented from jumping in the system working process, and the SOC error value caused by frequent change of bus current can be estimated in the battery system working process. The SOC error value caused by SOC estimation by adopting an ampere-hour integration method can be dynamically corrected, so that the calculation result of the SOC can be more accurate. Meanwhile, the longer standing time required by correcting the SOC by the open-circuit voltage is avoided, so that the battery management system adopting the method disclosed by the invention can be suitable for an environment with uninterrupted work.
In this specification, the invention has been described with reference to specific embodiments thereof. It will, however, be evident that various modifications and changes may be made thereto without departing from the broader spirit and scope of the invention. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.
Claims (8)
1. A method for dynamically correcting SOC errors, wherein a battery management system for an electric vehicle dynamically corrects errors in acquiring SOC of a battery system, the SOC errors including pole error and current peak error, the method comprising:
(1) the battery management system estimates a range error in the charging process of the battery system;
(2) the battery management system estimates the current peak value error in the working process of the battery system;
(3) the battery management system corrects the SOC of the battery system obtained by the battery management system according to the obtained range error and the current peak value error;
the battery management system obtains the SOC of the battery system through an ampere-hour integration method, and controls the battery system to charge by adopting a sectional constant-current charging stage in the charging process of the battery system;
the charging stage of the battery system comprises a large-current constant-current charging stage and a small-current constant-current charging stage, and the extreme value error is obtained in the step (1) through the following steps:
(1.1) the battery management system selects at least two battery monomers in the battery system and acquires the voltage values of the selected battery monomers;
(1.2) the battery management system sorts the selected battery monomers according to the voltage values of the selected battery monomers;
(1.3) the battery management system acquires the voltage difference between any two adjacent battery monomers after sequencing, and divides the voltage difference larger than the threshold value into a large current group and divides the voltage difference smaller than the threshold value into a small current group through a preset threshold value;
(1.4) the battery management system obtains a large-current charging extreme difference error according to the voltage difference of the large-current set and the voltage value of the single battery forming the voltage difference in the large-current constant-current charging stage; the battery management system acquires a low-current charging pole difference error according to the voltage difference of the low-current group and the voltage value of the battery monomer forming the voltage difference in the low-current constant-current charging stage;
and (1.5) the battery management system sums the large-current charging range error and the small-current charging range error to obtain the range error.
2. The method according to claim 1, wherein the step (1.4) of obtaining the range error according to the voltage difference and the voltage values of the battery cells constituting the voltage difference comprises:
the battery management system acquires the electric quantity required by the battery monomer with a lower voltage value in the battery monomers forming the voltage difference to increase the voltage difference, divides the electric quantity by the rated capacity of the battery monomer to acquire a single group of pole difference errors, and accumulates all the single group of pole difference errors after acquiring the single group of pole difference errors of all the two adjacent groups of battery monomers to acquire corresponding large-current charging pole difference errors or small-current charging pole difference errors.
3. The method for dynamically correcting SOC error of claim 1, wherein said step (1.1) is preceded by the steps of:
(1.0) the battery management system acquires the terminal voltage of each battery monomer in the battery system, and judges whether the change of the terminal voltage of each battery monomer enters a stable state, if so, the step (1.1) is carried out, and if not, the step continues to judge whether the voltage change of the current battery system enters the stable state.
4. The method of claim 3, wherein the determining whether the terminal voltage of each cell changes to a steady state specifically comprises:
the battery management system judges whether the terminal voltage of the battery cell acquired by the battery management system is in the rising channel.
5. The method for dynamically correcting SOC error of claim 1, wherein step (2) comprises the steps of:
(2.1) the battery management system acquires the number and intensity of positive peaks of bus current and the number and intensity of current feedback of the battery system in a preset time;
and (2.2) inquiring a current peak value SOC error table by the battery management system according to the number and intensity of the positive peak and the number and intensity of current feedback, and acquiring current peak value errors corresponding to the positive peak and the current feedback.
6. The method of dynamically correcting SOC error of claim 1, wherein said step (3) comprises the steps of:
(3.1) the battery management system acquires a battery cell with the highest voltage value in the battery system, and acquires the SOC after correcting the pole error according to the acquired pole error;
and (3.2) the battery management system corrects the current peak error of the SOC after the pole error is corrected according to the acquired current peak error.
7. The method for dynamically correcting SOC error according to claim 6, wherein in the step (3.1), the step of acquiring SOC corrected by the pole error by the battery management system comprises:
(3.1.1) the battery management system acquires the SOC _ H of the battery cell with the highest voltage value, and subtracts the pole difference error from the SOC _ H of the battery cell with the highest voltage value to acquire the SOC _ L of the battery cell with the lowest voltage value;
and (3.1.2) weighting the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value by the battery management system to obtain the SOC after the pole error is corrected.
8. The method according to claim 7, wherein the battery management system in step (3.1.2) weights the SOC _ H of the battery cell with the highest voltage value and the SOC _ L of the battery cell with the lowest voltage value according to the following formula to obtain the SOC after correcting the pole error:
SOC＝α×SOC_H+β×SOC_L；
wherein α and β are weighted values, α + β is 1, and α is SOC _ H/100.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810036405.9A CN108248427B (en) | 2018-01-15 | 2018-01-15 | Method for dynamically correcting SOC error |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810036405.9A CN108248427B (en) | 2018-01-15 | 2018-01-15 | Method for dynamically correcting SOC error |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108248427A CN108248427A (en) | 2018-07-06 |
| CN108248427B true CN108248427B (en) | 2021-01-01 |
Family
ID=62740677
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810036405.9A Active CN108248427B (en) | 2018-01-15 | 2018-01-15 | Method for dynamically correcting SOC error |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108248427B (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109038774B (en) * | 2018-07-17 | 2019-06-25 | 广州市凯捷电源实业有限公司 | A kind of drive system of electric automobile device and its storage battery power supply system |
| CN110879364B (en) * | 2018-08-27 | 2022-03-18 | 比亚迪股份有限公司 | Method and device for correcting SOC (state of charge) display of battery and electronic equipment |
| CN113075555B (en) | 2019-05-24 | 2024-08-23 | 宁德时代新能源科技股份有限公司 | SOC correction method and device, battery management system and storage medium |
| CN110386029B (en) * | 2019-07-23 | 2021-06-22 | 力高(山东)新能源技术有限公司 | Method for correcting SOC of lithium battery according to dynamic voltage |
| CN110470993B (en) * | 2019-09-23 | 2021-07-23 | 骆驼集团武汉光谷研发中心有限公司 | SOC algorithm for starting and stopping battery |
| CN110888060B (en) * | 2019-11-20 | 2021-10-15 | 先进储能材料国家工程研究中心有限责任公司 | SOC correction method for nickel-metal hydride battery pack |
| CN112158102B (en) * | 2020-09-04 | 2024-03-19 | 开沃新能源汽车集团股份有限公司 | Peak current control method of vehicle-mounted lithium battery system |
| CN114062943B (en) * | 2021-10-21 | 2024-02-09 | 合肥国轩高科动力能源有限公司 | Polarization abnormality early warning method and system for lithium ion battery system |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| KR100962856B1 (en) * | 2008-04-03 | 2010-06-09 | 현대자동차주식회사 | Method for estimating remaining capacity of battery |
| CN103969587B (en) * | 2014-01-17 | 2016-08-17 | 科力远混合动力技术有限公司 | A kind of hybrid vehicle electrokinetic cell SOC estimation method |
| CN103901348B (en) * | 2014-03-05 | 2016-06-01 | 清华大学 | It is applicable to the method for estimation of the remaining battery loading capacity of dynamic electric current operating mode |
| US9321368B2 (en) * | 2014-08-19 | 2016-04-26 | Fca Us Llc | Multi-step model predictive iterative techniques for battery system peak power estimation |
| WO2017179175A1 (en) * | 2016-04-14 | 2017-10-19 | 富士通株式会社 | Estimation device, estimation program, and charging control device |
| CN106526495A (en) * | 2016-11-22 | 2017-03-22 | 深圳市沃特玛电池有限公司 | Battery pack SOC evaluation method and battery pack SOC evaluation system |
| CN106970332B (en) * | 2017-05-04 | 2019-09-03 | 成都雅骏新能源汽车科技股份有限公司 | Based on the adaptive charging SOC modification method of feedback |
-
2018
- 2018-01-15 CN CN201810036405.9A patent/CN108248427B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN108248427A (en) | 2018-07-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108248427B (en) | Method for dynamically correcting SOC error | |
| CN108132442B (en) | storage battery joint state estimation method based on off-line data driving | |
| CN108663621B (en) | Charge state calculation method and system for power battery pack | |
| CN108717164B (en) | SOC calibration method and system for battery | |
| CN108663620B (en) | Power battery pack state of charge estimation method and system | |
| CN110161424B (en) | Method and system for detecting state of health of power battery and vehicle | |
| KR101248623B1 (en) | Accumulator device, and soc evaluation device and method thereof | |
| CN107852013B (en) | Monitoring and balancing capacity in lithium sulfur batteries arranged in series | |
| CN104965176B (en) | Battery cell state of health estimation method | |
| JP4759795B2 (en) | Rechargeable battery remaining capacity detection method | |
| CN109444762B (en) | Lithium ion battery health state estimation method based on data fusion | |
| CN107843852A (en) | It is a kind of to obtain off-line data to estimate the method for battery united state | |
| CN109856548B (en) | Power battery capacity estimation method | |
| CN104360285A (en) | Battery capacity correction method based on improved ampere-hour integral method | |
| RU2690724C1 (en) | Capacitance coefficient estimation device or capacitance coefficient estimation method | |
| CN104714182A (en) | Method and system for determining state-of-charge value of battery | |
| CN105548906A (en) | Method for dynamically estimating battery state of charge | |
| CN107817448B (en) | Method for online real-time monitoring of battery electric quantity suitable for complex working conditions | |
| CN109515251B (en) | Lithium battery pack balance control method for hybrid power | |
| CN113311347A (en) | Apparatus, method and system for estimating available state of charge of battery | |
| CN110320477B (en) | SOC (State of Charge) calculation method and device of power battery pack and electric automobile | |
| CN110794306A (en) | Lithium iron phosphate SOC terminal correction method | |
| CN115754736A (en) | SOC calibration method and device for charging and discharging tail ends of energy storage system | |
| CN112698209A (en) | SOC tail end calibration method of battery energy storage system | |
| CN111537901B (en) | Battery power state measuring and calculating method, battery pack and vehicle |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |