CN-117681712-B - Vehicle battery charging control method and system

CN117681712BCN 117681712 BCN117681712 BCN 117681712BCN-117681712-B

Abstract

The invention discloses a vehicle battery charging control method and system, and relates to the field of automobiles. The method comprises the steps of obtaining available data through an interactive charging system, obtaining available charging current through calculation, obtaining a first weight, obtaining a second weight, obtaining a third weight through taking the minimum value of the first weight and the second weight, obtaining set charging current through multiplying the available charging current by the third weight, obtaining battery internal resistance based on battery temperature and SOC, obtaining battery internal resistance, multiplying the battery internal resistance by the set charging current, obtaining battery internal resistance voltage, obtaining OCV voltage, obtaining corrected battery total voltage, obtaining a corresponding preset differential pressure voltage window value, adding the preset differential pressure voltage window value to the corrected battery total voltage, obtaining limited charging voltage, and sending the set charging current and the limited charging voltage to a charger as control signals. The technical problem that the battery state is difficult to monitor in real time in the prior art is solved, and the safe and efficient technical effect of battery charging is achieved.

Inventors

YU BO
GU YUHONG
JIANG WEI
YANG DANQING
Xue Dangyu

Assignees

沈阳金晨汽车技术开发有限公司

Dates

Publication Date: 20260505
Application Date: 20231208

Claims (7)

1. A battery charge control method for a vehicle, comprising: The interactive charging system acquires available data, wherein the available data comprises maximum output power, battery chargeable power, real-time total battery voltage, single highest voltage, battery temperature and SOC; Calculating and obtaining a chargeable current based on the maximum output power and the chargeable power of the battery by combining the real-time total battery voltage; Acquiring a first weight value based on the real-time battery total voltage table-lookup first data structure, acquiring a second weight value based on the battery cell highest voltage table-lookup second data structure, acquiring a third weight value by taking the minimum value of the first weight value and the second weight value, and obtaining the table-lookup value of the data structure as calibration; multiplying the available charging current by the third weight to obtain a set charging current output by a set charger; based on the battery temperature and the SOC, obtaining the battery internal resistance through looking up a fourth data structure, and multiplying the battery internal resistance by the set charging current to obtain the battery internal resistance voltage; Based on the battery temperature and the SOC, obtaining an OCV voltage through looking up a fifth data structure, and obtaining a corrected battery total voltage according to the third weight, the battery internal resistance voltage and the OCV voltage; based on the set charging current, obtaining a corresponding preset differential voltage window value through looking up a third data structure, adding the preset differential voltage window value to the total corrected battery voltage, and obtaining a limited charging voltage which is limited to the output of the charger; And sending the set charging current and the limit charging voltage to a charger as control signals.
2. The method as recited in claim 1, further comprising: In the charging process, monitoring the total voltage of the battery and the change of the voltage of the battery cell in real time, and obtaining the measured total voltage of the battery and the measured voltage of the battery cell; acquiring an adjustment first weight and an adjustment second weight according to the total voltage of the measured battery and the voltage of the measured battery cell; and dynamically adjusting the set charging current according to the first weight and the second weight.
3. The method of claim 2, wherein dynamically adjusting the set charging current based on adjusting the first weight and adjusting the second weight comprises: The larger the total voltage of the measured battery is, the smaller the first weight is, the larger the voltage of the measured battery is, and the smaller the second weight is, wherein the range of the first weight and the second weight is 0 to 1; during battery charging, the set charging current gradually decreases as the measured total battery voltage and the measured cell voltage increase.
4. The method of claim 1, wherein calculating a providable charge current based on the maximum output power and the battery chargeable power in combination with the real-time battery total voltage comprises: Comparing the maximum output power with the chargeable power of the battery, and obtaining the available power according to the minimum value of the comparison result; dividing the available power by the total voltage of the real-time battery to obtain the available charging current.
5. The method of claim 1, wherein obtaining a corrected total battery voltage based on the third weight, the internal battery voltage, and the OCV voltage comprises: Adding the battery internal resistance voltage and the OCV voltage to obtain a first voltage; Taking the OCV voltage as a second voltage; And using the third weight as a weight, and performing weighted calculation on the first voltage and the second voltage to obtain the total voltage of the battery, wherein the weighted calculation formula is as follows: U Total (S) =wU 1 +（1-w）U 2 Wherein U Total (S) is the total voltage of the battery, w is the third weight, U 1 is the first voltage, and U 2 is the second voltage.
6. The method of claim 1 wherein the look-up table of the third data structure is obtained for calibration and comprises different values of the output current of the battery, each value corresponding to a predetermined differential voltage window value, and the predetermined differential voltage window value satisfies the differential voltage between the output voltage of the battery and the total voltage of the battery.
7. A battery charge control system for a vehicle, the system comprising: the data acquisition module is used for acquiring available data of the interactive charging system, wherein the available data comprise maximum output power, battery chargeable power, real-time battery total voltage, single highest voltage, battery temperature and SOC; The first calculation module is used for calculating and obtaining the available charging current based on the maximum output power and the battery chargeable power and combined with the real-time battery total voltage; The weight acquisition module is used for acquiring a first weight based on the real-time battery total voltage table-lookup first data structure, acquiring a second weight based on the battery cell highest voltage table-lookup second data structure, acquiring a third weight by taking the minimum value of the first weight and the second weight, and calibrating the table-lookup value of the data structure; the second calculation module is used for multiplying the available charging current by the third weight to obtain a set charging current output by a set charger; The internal resistance acquisition module is used for acquiring the internal resistance of the battery through looking up a fourth data structure based on the temperature and the SOC of the battery, multiplying the internal resistance of the battery by the set charging current and acquiring the internal resistance voltage of the battery; The voltage acquisition module is used for acquiring OCV voltage through looking up a fifth data structure based on battery temperature and SOC, and acquiring corrected battery total voltage according to the third weight, the battery internal resistance voltage and the OCV voltage; The voltage limiting module is used for obtaining a corresponding preset differential voltage window value through looking up a third data structure based on the set charging current, adding the preset differential voltage window value to the corrected total voltage of the battery, and obtaining a limiting charging voltage for limiting the output of the charger; And the sending module is used for sending the set charging current and the limit charging voltage to a charger as control signals.

Description

Vehicle battery charging control method and system Technical Field The invention relates to the field of automobiles, in particular to a method and a system for controlling charging of a vehicle battery. Background With the rapid increase of global economy, the environmental pollution is also brought along, and green environmental protection is a topic of attention. The automobile is taken as a main tool for people to travel, brings convenience to people and causes pollution to the air in cities to a certain extent, and the plug-in hybrid electric vehicle has the power performance of the traditional automobile and the environmental protection economy of the pure electric vehicle, and stands out in a plurality of new energy automobiles. Charging is a main function of a plug-in hybrid electric vehicle, and how to safely and efficiently charge a battery is a focus of attention. The safe and efficient charging control method not only can ensure the use safety of the vehicle and improve the utilization rate and service life of the battery, but also can reduce the charging time. However, conventional vehicle battery charging methods often lack accurate monitoring of battery status, which can lead to overcharging or undercharging of the battery, thereby affecting battery life and performance, and even causing safety issues. Disclosure of Invention The embodiment of the application provides a vehicle battery charging control method and system, which solve the technical problem that the state of a battery is difficult to monitor in real time in the prior art. In view of the above problems, the embodiments of the present application provide a method and a system for controlling charging of a vehicle battery. In a first aspect of an embodiment of the present application, there is provided a battery charge control method for a vehicle, the method including: The interactive charging system acquires available data, wherein the available data comprises maximum output power, battery chargeable power, real-time total battery voltage, single highest voltage, battery temperature and SOC; Calculating and obtaining a chargeable current based on the maximum output power and the chargeable power of the battery by combining the real-time total battery voltage; Acquiring a first weight value based on the real-time battery total voltage table-lookup first data structure, acquiring a second weight value based on the battery cell highest voltage table-lookup second data structure, acquiring a third weight value by taking the minimum value of the first weight value and the second weight value, wherein the table-lookup value of the data structure is obtained by calibration; multiplying the available charging current by the third weight to obtain a set charging current output by a set charger; based on the battery temperature and the SOC, obtaining the battery internal resistance through looking up a fourth data structure, and multiplying the battery internal resistance by the set charging current to obtain the battery internal resistance voltage; Based on the battery temperature and the SOC, obtaining an OCV voltage through looking up a fifth data structure, and obtaining a corrected battery total voltage according to the third weight, the battery internal resistance voltage and the OCV voltage; based on the set charging current, obtaining a corresponding preset differential voltage window value through looking up a third data structure, adding the preset differential voltage window value to the total corrected battery voltage, and obtaining a limited charging voltage which is limited to the output of the charger; And sending the set charging current and the limit charging voltage to a charger as control signals. In a second aspect of the embodiment of the present application, there is provided a battery charge control system for a vehicle, the system including: the data acquisition module is used for acquiring available data of the interactive charging system, wherein the available data comprise maximum output power, battery chargeable power, real-time battery total voltage, single highest voltage, battery temperature and SOC; The first calculation module is used for calculating and obtaining the available charging current based on the maximum output power and the battery chargeable power and combined with the real-time battery total voltage; The weight acquisition module is used for acquiring a first weight based on the real-time battery total voltage table-lookup first data structure, acquiring a second weight based on the battery cell highest voltage table-lookup second data structure, acquiring a third weight by taking the minimum value of the first weight and the second weight, and the table-lookup value of the data structure is obtained by calibration; the second calculation module is used for multiplying the available charging current by the third weight to obtain a set charging current output by a set charger; The internal resi