CN-120229147-B - New energy automobile power battery pack temperature control method

CN120229147BCN 120229147 BCN120229147 BCN 120229147BCN-120229147-B

Abstract

The invention relates to the technical field of new energy automobiles, and particularly discloses a temperature control method of a power battery pack of a new energy automobile, which comprises the steps of determining the current temperature abnormality degree of the battery pack based on current working condition records of the new energy automobile, dynamic battery pack temperature models under each working condition and actual temperature record data of the battery pack; when the abnormal degree of the current temperature of the battery pack exceeds an abnormal degree threshold, the current aging factor of the battery pack is evaluated, the temperature influence coefficient of the first battery pack is determined based on the current aging factor of the battery pack, the temperature influence coefficient of the second battery pack is determined based on the current environment temperature, the abnormal degree of the current temperature of the battery pack is corrected based on the temperature influence coefficient of the first battery pack and the temperature influence coefficient of the second battery pack, the liquid cooling strategy of the battery pack is determined, and the liquid cooling equipment is started to cool the battery pack, so that the cooling operation can be accurately regulated and controlled according to the actual abnormal temperature condition, and the temperature of the battery pack is effectively controlled.

Inventors

Bian Anhua
XU WENHAI
YANG SHUGEN
XU ZHIPENG

Assignees

盐城工业职业技术学院

Dates

Publication Date: 20260505
Application Date: 20250516

Claims (8)

1. The temperature control method of the power battery pack of the new energy automobile is characterized by comprising the following steps of: s1, determining the current temperature abnormality degree of a battery pack based on current working condition records of a new energy automobile, a dynamic battery pack temperature model under each working condition and actual temperature record data of the battery pack; s2, when the current temperature abnormality degree of the battery pack exceeds an abnormality degree threshold, evaluating the current aging factor of the battery pack based on the use record of the battery pack of the new energy automobile, determining a first battery pack temperature influence coefficient based on the current aging factor of the battery pack, and determining a second battery pack temperature influence coefficient based on the current environment temperature; S3, correcting the current temperature abnormality degree of the battery pack based on the first battery pack temperature influence coefficient and the second battery pack temperature influence coefficient to obtain a corrected temperature abnormality degree of the battery pack, wherein the method comprises the following steps: Generating a continuous aging factor sequence based on the current aging factor, and substituting each aging factor contained in the continuous aging factor sequence into a function model of the aging factor of the battery pack and the temperature influence coefficient of the battery pack of the new energy automobile of the current model under the current working condition and the current environmental data of the new energy automobile to obtain a first influence coefficient sequence; Generating a continuous environment temperature sequence based on the current environment temperature, substituting each environment temperature in the continuous environment temperature sequence into a function model of the environment temperature and the temperature influence coefficient of the new energy automobile battery pack of the current model under the corresponding and consistent conditions of the current working condition, the current aging factor, all the remaining environment data except the environment temperature and the current environment data of the new energy automobile, and obtaining a second influence coefficient sequence; Correcting the current temperature abnormality degree of the battery pack based on the first battery pack temperature influence coefficient to obtain a first corrected abnormality degree; correcting the current temperature abnormality degree of the battery pack based on the second battery pack temperature influence coefficient to obtain a second corrected abnormality degree; Aligning the continuous aging factor sequence and the continuous environment temperature sequence, and summarizing all the residual environmental data except the environmental temperature corresponding and consistent with the current working condition and the current environmental data of the new energy automobile as a single-group instance retrieval basis; determining the actual correction temperature abnormality degree based on the battery pack temperature change data of the new energy automobile according with the current model when each group of examples is searched; Respectively taking a first influence coefficient and a second influence coefficient with the same sequencing value in the first influence coefficient sequence and the second influence coefficient sequence as an abscissa value and an ordinate value, and marking the coordinate of the point to be corrected corresponding to each sequencing value in a preset two-dimensional coordinate system; Meanwhile, taking each actual corrected temperature abnormality degree determined by the continuous aging factor sequence and the continuous environment temperature sequence corresponding to the same sorting value as an abscissa value and an ordinate value at the same time, and marking an anchor point coordinate corresponding to each sorting value in a preset two-dimensional coordinate system; The vector pointed by the coordinates of the point to be corrected of each sorting value to the coordinates of the corresponding anchor point is taken as a two-dimensional correction vector; Determining the interpolation distance of each two-dimensional correction vector based on the starting point coordinates of all the two-dimensional correction vectors and the point coordinates marked in a preset two-dimensional coordinate system by taking the first correction abnormality degree and the second correction abnormality degree as an abscissa value and an ordinate value respectively; Calculating a two-dimensional correction vector under the first correction abnormality degree and the second correction abnormality degree based on all the two-dimensional correction vectors and the corresponding interpolation distances; obtaining the corrected temperature abnormality degree of the battery pack based on the two-dimensional correction vector under the first corrected abnormality degree and the second corrected abnormality degree; And S4, determining a liquid cooling strategy of the battery pack based on the corrected temperature abnormality degree of the battery pack, and starting the liquid cooling equipment to cool the battery pack based on the liquid cooling strategy of the battery pack.
2. The method for controlling the temperature of the power battery pack of the new energy automobile according to claim 1, wherein S1, determining the current temperature abnormality degree of the battery pack based on the current working condition record of the new energy automobile, the dynamic battery pack temperature model under each working condition and the actual temperature record data of the battery pack, comprises: Determining a working condition type sequence and a duration time of each working condition type of the new energy automobile in a current complete continuous working period based on the current working condition record of the new energy automobile; Substituting the working condition type sequence of the new energy automobile in the current complete continuous working period and the duration period of each working condition type into the dynamic battery pack temperature model under all working conditions to determine ideal temperature record data of the battery pack in the current complete continuous working period; And determining the current temperature abnormality degree of the battery pack based on part of actual temperature record data of the battery pack in the current complete continuous working period and ideal temperature record data of the battery pack in the current complete continuous working period.
3. The method for controlling the temperature of a power battery pack of a new energy vehicle according to claim 2, wherein determining the current temperature abnormality degree of the battery pack based on a part of actual temperature record data of the battery pack within the current complete continuous operation period and ideal temperature record data of the battery pack within the current complete continuous operation period, comprises: Screening all abnormal temperature values in partial actual temperature record data in the current complete continuous working period in the actual temperature record data of the battery pack, and determining the occurrence period of all abnormal temperature values; Determining a first temperature abnormality degree of the battery pack based on all the abnormal temperature values and the corresponding occurrence periods; Calculating the deviation degree of partial actual temperature record data of the battery pack in the current complete continuous working period and ideal temperature record data of the battery pack in the current complete continuous working period, and taking the deviation degree as a second temperature abnormality degree of the battery pack; the current temperature abnormality degree of the battery pack is determined based on the first temperature abnormality degree and the second temperature abnormality degree of the battery pack.
4. The method for controlling the temperature of a power battery pack of a new energy vehicle according to claim 1, wherein estimating the current aging factor of the battery pack based on the usage record of the battery pack of the new energy vehicle comprises: Determining the charge and discharge times, the total use duration, the environmental record data in each use process, the charge and discharge depth and the charge and discharge multiplying power of each charge and discharge process of the battery pack based on the use record of the battery pack of the new energy automobile; And carrying out integrated calculation analysis on the charge and discharge times, the total using time, the environmental record data in each using process, the charge and discharge depth and the charge and discharge multiplying power of each charge and discharge process of the battery pack based on a preset aging evaluation model, and determining the current aging factor of the battery pack.
5. The method for controlling the temperature of a power battery pack of a new energy automobile according to claim 1, wherein determining the first battery pack temperature influence coefficient based on the current aging factor of the battery pack comprises: evaluating aging factors of the collected battery packs of the new energy automobiles with the current models at different moments based on the collected use records of the battery packs of the new energy automobiles with the current models; Based on the collected aging factors of a large number of new energy automobile battery packs of the current model at different moments and corresponding battery pack temperature change data of all the new energy automobiles of the current model in a time period under the same working condition and the same environmental data, establishing a function model of the aging factors of the battery packs and the temperature influence coefficients of the new energy automobile battery packs of the current model under each working condition and each environmental data; Substituting the current aging factor of the battery pack into a function model of the aging factor of the battery pack and the temperature influence coefficient of the battery pack of the new energy automobile with the current model under the current working condition and the current environmental data of the new energy automobile, and determining the temperature influence coefficient of the first battery pack.
6. The method for controlling the temperature of a power battery pack of a new energy automobile according to claim 1, wherein determining the second battery pack temperature influence coefficient based on the current ambient temperature comprises: Based on collected battery pack temperature change data when a large number of battery packs of new energy automobiles of the current model are in the same working condition, the same aging factors and all environmental data except the environmental temperature are corresponding to the current environmental data of the new energy automobiles and the environmental temperature is different, establishing a function model under the condition that the temperature influence coefficients of the battery packs of the new energy automobiles of the current model are in the corresponding consistence with the current environmental data of the new energy automobiles under each working condition, each aging factor and all environmental data except the environmental temperature; Substituting the current environment temperature into a function model of the temperature influence coefficient of the battery pack of the new energy automobile with the current model under the corresponding and consistent conditions of the current working condition, the current aging factor, all the remaining environment data except the environment temperature and the current environment data of the new energy automobile, and determining the temperature influence coefficient of the second battery pack.
7. The method according to claim 1, wherein obtaining the corrected temperature abnormality degree of the battery pack based on the two-dimensional correction vector at the first corrected abnormality degree and the second corrected abnormality degree, comprises: Fitting corresponding anchor point coordinates based on the two-dimensional correction vectors under the first correction abnormality degree and the second correction abnormality degree and point coordinates marked by the first correction abnormality degree and the second correction abnormality degree as an abscissa value and an ordinate value in a preset two-dimensional coordinate system respectively; Judging whether the abscissa deviation degree of the corresponding anchor point coordinate is smaller than a preset deviation degree threshold value, if yes, taking the average value of the corresponding anchor point coordinate as the corrected temperature abnormality degree of the battery pack, otherwise, acquiring a new continuous aging factor sequence and a continuous environment temperature sequence, determining a new two-dimensional correction vector under the first corrected abnormality degree and the second corrected abnormality degree based on the new continuous aging factor sequence and the continuous environment temperature sequence until the abscissa deviation degree of the new anchor point coordinate determined based on the new two-dimensional correction vector does not exceed the preset deviation degree threshold value, and taking the average value of the corresponding anchor point coordinate as the corrected temperature abnormality degree of the battery pack.
8. The method for controlling the temperature of the power battery pack of the new energy automobile according to claim 1, wherein S4 is characterized in that the liquid cooling strategy of the battery pack is determined based on the corrected temperature abnormality degree of the battery pack, and the liquid cooling equipment is started to cool the battery pack based on the liquid cooling strategy of the battery pack, and the method comprises the following steps: constructing a liquid cooling strategy generation model of the battery pack; inputting the corrected temperature abnormality degree of the battery pack into a liquid cooling strategy generation model of the battery pack to obtain a liquid cooling strategy of the battery pack; and starting the liquid cooling equipment to cool the battery pack based on the liquid cooling strategy of the battery pack.

Description

New energy automobile power battery pack temperature control method Technical Field The invention relates to the technical field of new energy automobiles, in particular to a temperature control method of a power battery pack of a new energy automobile. Background Along with the enhancement of environmental awareness and the transformation of energy structures, new energy automobiles are rapidly developed. The power battery pack is used as a core component of the new energy automobile, and the performance and the service life of the power battery pack directly influence the overall performance of the automobile. Temperature is a key factor affecting the performance and life of a power battery, and too high or too low a temperature can lead to reduced charge and discharge efficiency, accelerated capacity fade, and even cause safety problems. Therefore, an efficient temperature control method for the power battery pack of the new energy automobile is important. The battery pack can be ensured to work in a proper temperature range, the charge and discharge performance of the battery is improved, the service life of the battery is prolonged, and the endurance mileage and the safety of a new energy automobile are further improved. The method is not only helpful for enhancing the competitiveness of the new energy automobile in the market, but also accords with the concept of sustainable development, and has important significance for promoting the healthy development of the new energy automobile industry. Along with the continuous expansion of new energy automobile markets, advanced temperature control technology must have wider application prospect, and powerful support is provided for the prosperity of new energy automobile industry. However, the existing new energy automobile power battery pack temperature control technology has some disadvantages. And meanwhile, when the temperature abnormality exceeds a threshold value, the temperature abnormality degree cannot be corrected by combining a battery aging factor and the ambient temperature, so that an accurate and effective liquid cooling strategy cannot be made, the performance and the service life of the battery pack are further influenced, and the safe and stable operation of a new energy automobile is threatened. Therefore, the invention provides a temperature control method for the power battery pack of the new energy automobile. Disclosure of Invention The invention provides a temperature control method for a power battery pack of a new energy automobile, which can synthesize various key factors, accurately identify the temperature abnormality of the battery pack and provide accurate basis for taking reasonable measures later by determining the current temperature abnormality degree of the battery pack based on the current working condition record, the dynamic battery pack temperature model and the actual temperature record data of the new energy automobile. When the temperature abnormality degree exceeds the threshold value, the aging factor is evaluated according to the battery pack use record, so that the temperature influence coefficient of the first battery pack is determined, and meanwhile, the temperature influence coefficient of the second battery pack is determined by combining the current environment temperature, so that the aging of the battery and the influence of the environment factors on the temperature are comprehensively considered, and the control strategy is more scientific and specific. The temperature anomaly degree is corrected by utilizing the two influence coefficients, so that the corrected temperature anomaly degree which is more fit with the actual situation is obtained, the accuracy of temperature anomaly judgment is effectively improved, and deviation caused by single factor judgment is avoided. The liquid cooling strategy is determined based on the corrected temperature abnormality degree, the liquid cooling equipment is started, the cooling operation can be accurately regulated and controlled according to the actual temperature abnormality condition, the temperature of the battery pack is effectively controlled, the energy waste and equipment loss caused by excessive cooling are avoided, the performance and the service life of the battery pack are ensured, and the overall operation efficiency and the safety of the new energy automobile are improved. The invention provides a temperature control method of a power battery pack of a new energy automobile, which comprises the following steps: s1, determining the current temperature abnormality degree of a battery pack based on current working condition records of a new energy automobile, a dynamic battery pack temperature model under each working condition and actual temperature record data of the battery pack; s2, when the current temperature abnormality degree of the battery pack exceeds an abnormality degree threshold, evaluating the current aging factor of the battery pack ba