CN-122017569-A - Battery parameter determining method, device, equipment and storage medium

CN122017569ACN 122017569 ACN122017569 ACN 122017569ACN-122017569-A

Abstract

The application relates to a battery parameter determining method, a battery parameter determining device, battery parameter determining equipment and a storage medium. The method comprises the steps of determining terminal voltage, current, battery temperature and state of charge of a battery at the current moment in the charging and discharging process of the battery, determining open-circuit voltage of the battery at the current moment based on the battery temperature and the state of charge, obtaining an actual voltage difference at the current moment according to the terminal voltage and the open-circuit voltage, correcting an intermediate parameter at the previous moment according to the actual voltage difference and a predicted voltage difference to obtain the intermediate parameter at the current moment, predicting the predicted voltage difference for the current moment based on the intermediate parameter at the previous moment, obtaining the battery parameter at the current moment based on the intermediate parameter at the current moment and a parameter mapping relation, and describing multiple groups of corresponding relations between the intermediate parameter and the battery parameter by the parameter mapping relation. By adopting the method, the identification accuracy of the battery parameters can be improved.

Inventors

CHENG XU
Jiang Kaishun
WEN QIAN
LUO JING
JIE LIZHU
YANG QINGYIN

Assignees

赛力斯汽车有限公司

Dates

Publication Date: 20260512
Application Date: 20260323

Claims (10)

1. A method of determining battery parameters, the method comprising: in the charging and discharging process of the battery, determining terminal voltage, current, battery temperature and state of charge of the battery at the current moment; Determining an open circuit voltage of the battery at the current time based on the battery temperature and the state of charge quantity; Obtaining an actual voltage difference at the current moment according to the terminal voltage and the open-circuit voltage, and correcting an intermediate parameter at the previous moment according to the actual voltage difference and a predicted voltage difference to obtain the intermediate parameter at the current moment; And obtaining the battery parameters of the battery at the current moment based on the intermediate parameters and the parameter mapping relation at the current moment, wherein the parameter mapping relation is used for describing a plurality of groups of corresponding relations between the intermediate parameters and the battery parameters.
2. The method according to claim 1, wherein the correcting the intermediate parameter at the previous time according to the actual voltage difference and the predicted voltage difference to obtain the intermediate parameter at the current time includes: Determining a voltage difference error at the current moment according to the actual voltage difference and the predicted voltage difference; determining gain of the current moment based on a forgetting factor of the previous moment and a regression vector of the current moment, wherein the forgetting factor of the previous moment is determined according to a voltage difference error of the previous moment; and correcting the intermediate parameter of the previous moment based on the gain of the current moment and the voltage difference error of the current moment to obtain the intermediate parameter of the current moment.
3. The method of claim 2, wherein determining the voltage difference error at the current time based on the actual voltage difference and a predicted voltage difference comprises: Determining an intermediate parameter at the previous moment, and obtaining a predicted voltage difference according to the intermediate parameter at the previous moment and the regression vector at the current moment; And obtaining the voltage difference error at the current moment based on the difference between the actual voltage difference and the predicted voltage difference.
4. The method of claim 1, wherein the determining an open circuit voltage of the battery at the current time based on the battery temperature and the state of charge quantity comprises: acquiring an open-circuit voltage mapping relation, wherein the open-circuit voltage mapping relation comprises a plurality of groups of corresponding relations among battery temperature, state of charge quantity and open-circuit voltage; And determining the open-circuit voltage of the battery at the current moment based on the battery temperature, the state-of-charge quantity and the open-circuit voltage mapping relation.
5. The method according to claim 1, wherein the method further comprises: Determining an equivalent circuit of the battery, wherein the equivalent circuit comprises ohmic internal resistance, polarized internal resistance and polarized capacitance; Determining a transfer function relationship between an open circuit voltage and current of the battery and the equivalent circuit; And obtaining the parameter mapping relation based on the transfer function relation, wherein the parameter mapping relation comprises a plurality of groups of corresponding relations among the intermediate parameter, the value of the ohmic internal resistance, the value of the polarization internal resistance and the value of the polarization capacitor.
6. The method according to any one of claims 1 to 5, further comprising: Obtaining respective battery parameters of the battery at each moment in the charge and discharge process; Under the constraint condition of physical characteristics of the battery, interpolation processing is carried out on respective battery parameters at each moment to obtain a high-density parameter table of the battery, wherein the high-density parameter table comprises battery parameters corresponding to the battery under different working conditions.
7. The method according to claim 6, wherein the interpolating process is performed for each battery parameter at each time under the physical characteristic constraint condition of the battery to obtain the high-density parameter table of the battery, and the method comprises at least one of the following steps: Under the constraint condition of physical characteristics of the battery, interpolation processing is carried out on respective first battery parameters at each moment according to a preset state of charge threshold value to obtain a high-density parameter table of the battery, wherein the first battery parameters comprise values of ohmic internal resistance and/or values of polarization internal resistance in an equivalent circuit of the battery; Under the constraint condition of the physical characteristics of the battery, interpolation processing is carried out on respective second battery parameters at each moment based on a linear interpolation and extrapolation processing mechanism according to a preset state of charge threshold value to obtain a high-density parameter table of the battery, wherein the second battery parameters comprise values of polarization capacitors in an equivalent circuit of the battery.
8. A battery parameter determination apparatus, the apparatus comprising: The working parameter determining module is used for determining terminal voltage, current, battery temperature and state of charge of the battery at the current moment in the charging and discharging process of the battery; An open circuit voltage determination module for determining an open circuit voltage of the battery at the current time based on the battery temperature and the state of charge quantity; The correction processing module is used for obtaining the actual voltage difference at the current moment according to the terminal voltage and the open-circuit voltage, correcting the intermediate parameter at the previous moment according to the actual voltage difference and the predicted voltage difference, and obtaining the intermediate parameter at the current moment; The parameter mapping module is used for obtaining the battery parameters of the battery at the current moment based on the intermediate parameters and the parameter mapping relation at the current moment, and the parameter mapping relation is used for describing a plurality of groups of corresponding relations between the intermediate parameters and the battery parameters.
9. An electronic device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any one of claims 1 to 7 when the computer program is executed.
10. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 7.

Description

Battery parameter determining method, device, equipment and storage medium Technical Field The present application relates to the field of battery management technologies, and in particular, to a method, an apparatus, a device, and a storage medium for determining battery parameters. Background The power Battery is used as a core component of an electric automobile and an energy storage system, and accurate modeling and parameter identification are key technical challenges for improving the performance of a Battery management system (Battery MANAGEMENT SYSTEM, BMS), guaranteeing the safety of the system and promoting the development of the Battery. In the related art, on-line battery parameter estimation is performed by relying on an equivalent circuit model, an electrochemical model or a data driving method, so that the dynamic characteristics of the battery can be reflected, and support is provided for state of charge and state of health estimation. However, the recognition accuracy of the battery parameters in the related art is low. Disclosure of Invention In view of the above, the present application provides a battery parameter determination method, apparatus, device, and storage medium capable of improving the accuracy of battery parameter identification. In a first aspect, the present application provides a method for determining parameters of a battery, including: In the charging and discharging process of the battery, determining terminal voltage, current, battery temperature and state of charge of the battery at the current moment; Determining an open-circuit voltage of the battery at the current moment based on the battery temperature and the state of charge quantity; Obtaining an actual voltage difference at the current moment according to the terminal voltage and the open-circuit voltage, and correcting an intermediate parameter at the previous moment according to the actual voltage difference and a predicted voltage difference to obtain the intermediate parameter at the current moment; And obtaining the battery parameters of the battery at the current moment based on the intermediate parameters and the parameter mapping relation at the current moment, wherein the parameter mapping relation is used for describing a plurality of groups of corresponding relations between the intermediate parameters and the battery parameters. According to the battery parameter determining method, the open-circuit voltage is determined based on the battery temperature and the state of charge, temperature compensation can be introduced, the accuracy of the open-circuit voltage is ensured, the actual voltage difference at the current moment is obtained according to the terminal voltage and the open-circuit voltage, the intermediate parameter is corrected according to the actual voltage difference and the predicted voltage difference, and the battery parameter is obtained based on the intermediate parameter and the mapping relation, so that an adaptive closed-loop identification mechanism based on error feedback is formed, the real-time tracking capability and the anti-interference robustness of the dynamic characteristic change of the battery are improved, the battery parameter which changes along with the working condition can be accurately identified, and the identification precision of the battery parameter is improved. In an alternative embodiment of the first aspect, the correction is performed on the intermediate parameter at the previous time according to the actual voltage difference and the predicted voltage difference to obtain the intermediate parameter at the current time, which includes determining a voltage difference error at the current time according to the actual voltage difference and the predicted voltage difference, determining a gain at the current time based on a forgetting factor at the previous time and a regression vector at the current time, the forgetting factor at the previous time being determined according to the voltage difference error at the previous time, the regression vector at the current time being obtained based on the current, the actual voltage difference at the previous time and the current at the previous time, and the correction is performed on the intermediate parameter at the previous time based on the gain at the current time and the voltage difference error at the current time to obtain the intermediate parameter at the current time. In the alternative embodiment, the middle parameter at the previous moment is corrected according to the gain at the current moment and the voltage difference error at the current moment, the trust degree of historical data is dynamically adjusted by introducing an adaptive mechanism, the tracking capability can be enhanced when the parameter is rapidly changed, and the estimation smoothness is kept in a steady state, so that the identification precision of the battery parameter is facilitated. In an alternative embodiment of the first a