Battery charging control method, charging and discharging control system and discharging control method

Abstract

The invention relates to a battery charging control method, a charging and discharging control system and a discharging control method. The battery charging control method provided by the invention is applied to a battery system comprising at least one group of batteries, and comprises the following steps: acquiring charging power of the batteries, and obtaining first charging current of the batteries according to the charging power; correcting the first charging current of the battery according to a pre-configured first charging correction coefficient to obtain a second charging current of the battery; determining a second charging correction coefficient of the battery according to the required charging amount of the battery; and correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain a third charging current of the battery, and charging the current battery pack based on the third charging current. According to the scheme, overcharge of the battery can be avoided, the consistency of the battery packs in the battery system is improved, reliable operation of the battery system is facilitated, and the service life of the battery system is prolonged.

Description

Technical Field

[0001] The present invention relates to the field of batteries, and in particular to a battery charging control method, a charging and discharging control system, and a discharging control method. Background Art

[0002] With the promotion and application of new energy technologies, power battery technology is gradually promoted and applied in locomotives. According to the different battery capacities, two or more groups are connected in parallel to meet application requirements. The charge and discharge balance within the battery pack is achieved by the battery supplier through the BMS (Battery Management System). The balance control between battery packs is achieved by the locomotive controller. During use, due to various factors such as ambient temperature, there will be large differences in power between groups and overcharging of batteries. If control is based solely on the power / current parameter table provided by the battery supplier, the consistency of SOC (battery power) between different groups cannot be achieved, which affects the reliable use of the power battery and reduces the battery life. Summary of the invention

[0003] In view of this, the present invention proposes a battery charging control method, a charging and discharging control system and a discharging control method, which solve the problems of large power difference between battery packs and battery overcharging in the existing power battery charging and discharging process.

[0004] In one aspect, an embodiment of the present invention provides a battery charging control method, which is applied to a battery system including at least one group of batteries. The method includes performing the following steps for each group of batteries: Acquiring a charging power of the battery, and obtaining a first charging current of the battery according to the charging power; Correcting a first charging current of the battery according to a pre-configured first charging correction coefficient to obtain a second charging current of the battery; determining a second charging correction factor of the battery according to the required charging amount of the battery; The second charging current of the battery is corrected according to the second charging correction coefficient of the battery to obtain a third charging current of the battery, and the current battery group is charged based on the third charging current.

[0005] In some implementations, correcting the first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery includes: The first charging correction coefficient and the first charging current are multiplied to obtain a second charging current of the battery.

[0006] In some embodiments, the battery system includes a plurality of batteries connected in parallel, and determining the second charging correction factor of the battery according to the required charging amount of the battery includes: According to the required charging power of the battery and the number of battery groups connected in parallel in the battery system, the required charging power average is obtained; A second charging correction coefficient of the battery is obtained according to the required charging power of the battery and the average of the required charging power.

[0007] In some implementations, obtaining a second charging correction factor of the battery according to the required charging power of the battery and the required charging power average includes: The second charging correction coefficient of the battery is obtained by dividing the required charging power of the battery by the average required charging power.

[0008] In some implementations, correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain a third charging current of the battery includes: comparing the battery power level with a third battery power threshold; When the battery power level is lower than or equal to the third battery power level threshold, the second charging current of the battery is corrected according to the second charging correction coefficient of the battery to obtain the third charging current of the battery.

[0009] In some embodiments, the method further comprises: When the battery power level is higher than the third battery power level threshold, the second charging correction coefficient is configured as a preset value, and the second charging current of the battery is corrected based on the second charging correction coefficient configured as the preset value to obtain a third charging current of the battery.

[0010] In some implementations, before obtaining the first charging current of each battery group, the method further includes: The first charging correction coefficient is configured according to the battery power and the single cell voltage, wherein the first charging correction parameter includes the power correction coefficient and the single cell voltage correction coefficient, wherein: a power correction coefficient, which is set to a first proportional coefficient when the battery power is lower than a first battery power threshold, and is set to a second proportional coefficient when the battery power is higher than a second battery power threshold, and changes linearly when the battery power is between the first battery power threshold and the second battery power threshold, wherein the first proportional coefficient is greater than the second proportional coefficient; The single cell voltage correction coefficient is set to a third proportional coefficient when the battery power is lower than the first voltage value, and is set to a fourth proportional coefficient when the battery power is higher than the second voltage value. The battery power changes linearly when the battery power is between the first voltage value and the second voltage value, wherein the third proportional coefficient is greater than the fourth proportional coefficient.

[0011] On the other hand, an embodiment of the present invention further provides a battery charge and discharge control system, comprising: The memory and the processor store computer instructions in the memory, and the processor executes the battery charging control method as described above by executing the computer instructions.

[0012] On the other hand, an embodiment of the present invention further provides a battery discharge control method, which is applied to the battery charge and discharge control system as described above. The battery discharge control method includes: Obtaining a first discharge correction coefficient of the battery according to the average available power of the battery system and the available power of each battery group; Acquire the discharge power of the battery, and obtain a first discharge current of the battery according to the discharge power; Correcting a first discharge current of the battery according to a first discharge correction coefficient of the battery to obtain a second discharge current of the battery; The corresponding battery is discharged according to the second discharge current.

[0013] In some embodiments, discharging the corresponding battery according to the second discharge current includes: calculating the total discharge power of the battery system according to the second discharge current of the battery; When the total discharge power meets the discharge power requirement value, discharging the corresponding battery according to the second discharge current; When the total discharge power does not meet the discharge power requirement value, the discharge power coefficient of the battery is obtained according to the discharge power of each group of batteries and the discharge power standard value of the battery, and the second discharge current of the battery is corrected according to the discharge power coefficient of the battery and the first discharge correction coefficient of the battery, and the corresponding battery is discharged based on the corrected second discharge current.

[0014] The present invention has at least the following beneficial effects: The present invention provides a battery charging control method and a battery discharging control method.

[0015] The battery charging control method provided by the present invention introduces a first charging correction coefficient and corrects the first charging current of the battery according to the battery power and the first charging correction coefficient, thereby avoiding overcharging of each group of batteries and improving the service life of the battery system. By introducing a second charging correction coefficient related to the power required by each group of batteries and the average value of the charging power required by the battery system to correct the corrected charging current of each group of batteries again, the power between each group of batteries can be kept consistent, the consistency between battery groups within the battery system is improved, the reliable operation of the battery system is facilitated, and the service life of the battery system is improved.

[0016] The battery discharge control method provided by the present invention corrects the discharge current of the battery by introducing a first discharge correction coefficient related to the average available power of the battery system and the available power of each group of batteries, thereby ensuring the balance of power between the groups of batteries in the battery system, improving the consistency between the battery groups within the battery system, contributing to the reliable operation of the battery system, and increasing the service life of the battery system. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.

[0018] Figure 1 A schematic diagram of an exemplary locomotive structure provided by the present invention; Figure 2 A flowchart of a battery charging control method provided by an embodiment of the present invention; Figure 3 A schematic diagram of a charging power curve provided by an embodiment of the present invention; Figure 4 A relationship diagram between battery power and power correction coefficient provided by an embodiment of the present invention; Figure 5 A diagram showing the relationship between a power correction coefficient and battery power provided by an embodiment of the present invention; Figure 6 A relationship diagram between a cell voltage and a cell voltage correction coefficient provided by an embodiment of the present invention; Figure 7 A relationship diagram between a second charging correction coefficient and battery power provided by an embodiment of the present invention; Figure 8 A relationship diagram between a second charging correction coefficient and battery power provided by an embodiment of the present invention; Fig. 9 A graph showing the relationship between the amount of power change and the amount of battery power provided by an embodiment of the present invention; Fig.10 A flow chart of a battery discharge control method provided by an embodiment of the present invention; Fig.11 A graph showing the relationship between the available power of a battery and the power of the battery provided in an embodiment of the present invention; Fig.12 A relationship diagram between a second discharge correction coefficient and battery power provided by an embodiment of the present invention; Fig.13A relationship diagram between the discharge power coefficients of other groups of batteries except the battery with the highest discharge power coefficient and the second discharge correction coefficient provided by an embodiment of the present invention; Fig.14 A relationship diagram of the discharge power coefficients of other battery groups except the battery with the highest discharge power coefficient, the second discharge correction coefficient and the highest discharge power coefficient provided by an embodiment of the present invention. DETAILED DESCRIPTION

[0019] In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.

[0020] It should be noted that all expressions using "first" and "second" in the embodiments of the present invention are for distinguishing two non-identical entities with the same name or non-identical parameters. It can be seen that "first" and "second" are only for the convenience of expression and should not be understood as limitations on the embodiments of the present invention. The subsequent embodiments will not explain this one by one.

[0021] With the promotion and application of new energy technologies, power battery technology has been gradually promoted and applied in locomotives. According to the different use requirements of power batteries and the power requirements of power batteries, two or more groups of batteries can be connected in parallel to meet the use requirements. In the related technology, the charge and discharge balance control within the battery pack is implemented by the battery supplier through the BMS (Battery Management System). The balance control between battery packs is implemented by the locomotive controller. During use, due to various factors such as ambient temperature, there will be large differences in power between groups and overcharging of batteries. If control is only based on the power / current parameter table provided by the battery supplier, the power consistency between different groups of batteries cannot be achieved, which affects the reliable use of the power battery and reduces the battery life.

[0022] Figure 1 A schematic diagram of an exemplary locomotive structure provided by the present invention.

[0023] like Figure 1 As shown, the locomotive includes a diesel generator set (G), a rectifier connected to the diesel generator set, a DC-DC converter and a traction inverter respectively connected to the rectifier, a power battery pack connected to the DC-DC converter, and a motor (M) connected to the traction inverter. The power battery pack is installed in a battery cabinet, including multiple groups of power batteries connected in parallel.

[0024] In the case of Figure 1 When the power battery shown is charged, the charging current is controlled by the charging parameter table provided by the battery supplier. The charging parameter table provided by the battery supplier is generally a charging power parameter table. Table 1 is an exemplary charging power parameter table.

[0025] Table 1

[0026] For example Figure 1 The specific process of charging the power battery pack shown is: according to the power and temperature of each power battery in the power battery pack, the charging power of the battery is obtained from the charging power parameter table, the charging current is calculated according to the charging power, and the power battery group is charged based on the charging current.

[0027] The above charging method charges the power battery with a constant current, which is easy to cause overcharging and shorten the battery life. Overcharging the battery will cause single cell voltage high protection, affecting the normal use of the battery.

[0028] In addition, the above charging method does not take into account the difference in power between each group of power batteries. Due to the influence of various factors such as environment and temperature, the charging process will also cause large differences in power between each group of power batteries, resulting in uneven charging between batteries and excessive single cell voltage, affecting the normal use of the battery and the battery life.

[0029] For example, when the ambient temperature is low, the single cell voltage of the power battery is high and fluctuates greatly. Obtaining the battery charging current solely by looking up the table can easily lead to overcharging of the battery, causing high single cell voltage protection and affecting the normal use of the battery.

[0030] The discharge process of the power battery pack is similar to the charging process of the power battery pack. The discharge process of the power battery pack is to obtain the discharge power of each power battery in the power battery pack from the discharge power parameter table according to the power and temperature of the battery, calculate the charging current according to the discharge power, and then discharge the power battery based on the discharge current.

[0031] This discharge method does not take into account the difference in power between each group of power batteries, which will lead to uneven discharge between battery packs within the power battery, affecting the reliable operation and service life of the power battery.

[0032] In view of this, in order to solve at least one of the above technical problems, the present invention provides a battery charging control method and a battery discharging control method.

[0033] The battery charging control method provided by the present invention comprises performing the following steps for each group of batteries: obtaining the charging power of the battery, and obtaining a first charging current of the battery according to the charging power; correcting the first charging current of the battery according to a pre-configured first charging correction coefficient to obtain a second charging current of the battery. Determining the second charging correction coefficient of the battery according to the required charging amount of the battery. Correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain a third charging current of the battery, and charging the current group of batteries based on the third charging current.

[0034] The battery charging control method introduces a first charging correction coefficient and corrects the first charging current of the battery according to the battery power and the first charging correction coefficient, thereby avoiding overcharging of each group of batteries and improving the service life of the battery system. By introducing a second charging correction coefficient related to the power required by each group of batteries and the average value of the charging power required by the battery system to correct the corrected charging current of each group of batteries again, the power between each group of batteries can be kept consistent, the consistency between battery groups within the battery system is improved, the reliable operation of the battery system is facilitated, and the service life of the battery system is improved.

[0035] The present invention is described in detail below in conjunction with embodiments and drawings.

[0036] A first aspect of an embodiment of the present invention provides a battery charging control method, which can be applied to a battery system including at least one group of batteries. Figure 2 As shown, the battery charging control method may include steps S21 to S24.

[0037] S21. Acquire the charging power of the battery, and obtain a first charging current of the battery according to the charging power.

[0038] In some examples, the corresponding charging power can be obtained from a charging power parameter table provided by a battery supplier according to the temperature and power of the battery, and the first charging current can be obtained according to the charging power and battery voltage of the battery.

[0039] In some examples, a charging power function may be generated by using the temperature, power and corresponding charging power in the charging power parameter table. According to the temperature and power of the battery and the charging power function, a corresponding charging power value is obtained, and the first charging current of the battery is calculated according to the charging power of the battery, thereby improving the accuracy of the obtained first charging current.

[0040] Taking the battery system with 4 groups of batteries connected in parallel as an example, the charging power function of each group of batteries can be expressed as: KW1 = f_KW(SOC1, BAT_Temp1) KW2 = f_KW(SOC2, BAT_Temp2) KW3 = f_KW(SOC3, BAT_Temp3) KW4 = f_KW(SOC4, BAT_Temp4).

[0041] Figure 3 A schematic diagram of a charging power curve provided by an embodiment of the present invention. Figure 3 It can be seen that the battery temperature has a significant impact on the battery charging power. When the temperature is high or low, the charging power is limited.

[0042] In some examples, charging current = charging power / battery voltage.

[0043] Still taking the battery system with 4 groups of batteries connected in parallel as an example, the charging current of each group of batteries can be expressed as: I1 = KW1 / Volt1 I2 = KW2 / Volt2 I3 = KW3 / Volt3 I4 = KW4 / Volt4.

[0044] Among them, Volt1~Volt4 represent the real-time voltage corresponding to the charging of batteries 1~4.

[0045] S22. Correct the first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery.

[0046] The first charging correction coefficient is related to the battery power and the single cell voltage. By correcting the first charging current with the first charging correction coefficient related to the battery power and the single cell voltage, the battery can be prevented from being overcharged and single cell voltage failure during battery charging can be effectively avoided.

[0047] S23. Determine a second charging correction coefficient of the battery according to the required charging amount of the battery.

[0048] The amount of charge required for a battery refers to the difference between the maximum charge of the battery and the current remaining charge of the battery. The maximum charge of the battery can be configured according to the actual application scenario, and the maximum configurable value is 100%. In order to protect the battery, it is generally set to be less than this value. In the embodiment of the present invention, for the convenience of calculation, the charge is dimensionless and the unit is percentage %.

[0049] The second charging correction coefficient of the battery can be obtained according to the required charging capacity of the battery and the average value of the charging capacity required by the battery system.

[0050] The average charging capacity required by the battery system refers to the average charging capacity required by all batteries included in the battery system.

[0051] S24, correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain a third charging current of the battery, and charging the current battery group based on the third charging current.

[0052] The second charging current of the battery is corrected according to a second charging correction coefficient related to the required charging amount of the battery and the average value of the charging amount required by the battery system, so as to obtain a third charging current of the battery. Each group of batteries in the battery system is charged by its corresponding third charging current, so that the charging consistency between each group of batteries can be ensured.

[0053] In the embodiment of the present invention, by introducing a first charging correction coefficient and correcting the first charging current of the battery according to the battery power and the first charging correction coefficient, overcharging of each group of batteries is avoided. By introducing a second charging correction coefficient related to the power required by each group of batteries and the average value of the charging power required by the battery system to correct the corrected charging current of each group of batteries again, the power between each group of batteries can be kept consistent, the consistency between the battery groups within the battery system is improved, the reliable operation of the battery system is facilitated, and the service life of the battery system is increased.

[0054] In some embodiments, the present invention Figure 2 Before step S21 of the illustrated embodiment, the battery charging control method provided by the embodiment of the present invention further includes: configuring a first charging correction coefficient according to the battery power and the cell voltage.

[0055] The first charging correction parameter includes a charge correction coefficient and a cell voltage correction coefficient.

[0056] The power correction coefficient is set to a first proportional coefficient when the battery power is lower than a first battery power threshold, and is set to a second proportional coefficient when the battery power is higher than a second battery power threshold. The battery power changes linearly when the battery power is between the first battery power threshold and the second battery power threshold, wherein the first battery power threshold is less than the second battery power threshold, and the first proportional coefficient is greater than the second proportional coefficient.

[0057] The cell voltage correction coefficient is set to a third proportional coefficient when the cell voltage is lower than the first voltage value, and is set to a fourth proportional coefficient when the cell voltage is higher than the second voltage value. The cell voltage changes linearly when it is between the first voltage value and the second voltage value, wherein the first voltage value is less than the second voltage value, and the third proportional coefficient is greater than the fourth proportional coefficient.

[0058] The first battery power threshold can be set according to the application scenario, for example, 55%, 60%, 75%, 85%, 90%, etc., but is not limited thereto.

[0059] The second battery power threshold can be set according to the application scenario, for example, 55%, 60%, 75%, 85%, 90%, 95%, etc., but is not limited thereto.

[0060] The first voltage value and the second voltage value are related to characteristics of the cells constituting the battery.

[0061] In a specific implementation, the charging current of each battery group can be adjusted according to the power correction coefficient and the single cell voltage correction coefficient of each battery group. The power correction coefficient is related to the battery power. When the battery power is high, the charging current is corrected to prevent overcharging of the battery. High battery power can be understood as battery power of 40%, 50%, 60%, 70%, 80%, 90%, 95%, etc., which is not specifically limited here.

[0062] Figure 4 A diagram showing the relationship between battery power and power correction coefficient provided by an embodiment of the present invention. In one example, Figure 4 As shown in the figure, when the battery capacity (SOC for short) is lower than 86%, the capacity correction factor is 100%, when the SOC reaches 90%, the capacity correction factor is 20%, and when the SOC is higher than 90%, the capacity correction factor is 0%. By correcting the first charging current of the battery through the capacity correction factor and the single cell voltage correction factor, overcharging and battery single cell voltage failure can be effectively avoided during battery charging.

[0063] Figure 5 A diagram of the relationship between a power correction factor and a battery power provided by an embodiment of the present invention. In one example, assuming that the battery system includes battery 1 and battery 2 connected in parallel, the power of battery 1 is SOC1, the power correction factor is scaleB1, the power of battery 2 is SOC2, the power correction factor is scaleB2, and the relationship between the power correction factor of battery 1 and battery 2 and the battery power is shown in the figure below. Figure 5 shown.

[0064] When the battery is nearly fully charged, the charging current can be reduced by using the current correction factor to effectively prevent overcharging and false charging.

[0065] It should be noted that the above examples are only intended to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention.

[0066] In a specific implementation, the charging current of each battery group can be adjusted according to the power correction coefficient and the cell voltage correction coefficient of each battery group, wherein the cell voltage correction coefficient is related to the cell voltage.

[0067] Figure 6 A diagram showing the relationship between a cell voltage and a cell voltage correction coefficient provided by an embodiment of the present invention. In one example, Figure 6As shown, when the monomer voltage is lower than 2510mV, the monomer voltage correction coefficient is 100%. When the monomer voltage reaches 2650mV, the monomer voltage correction coefficient is 0%. When the monomer voltage is in the range of 2510mV~2650mV, the monomer voltage changes linearly.

[0068] It should be understood that the purpose of the above examples is only to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention.

[0069] By correcting the first charging current of the battery by using the single cell voltage correction coefficient and the power correction coefficient, overcharging of the battery and battery single cell voltage failure during charging can be effectively avoided.

[0070] In some embodiments, the present invention Figure 2 In step S21 of the illustrated embodiment, correcting the first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery may include: multiplying the first charging correction coefficient and the first charging current to obtain the second charging current of the battery.

[0071] Specifically, the second charging current of each battery group of the battery system can be expressed as: The second charging current=the first charging current×the first charging correction coefficient.

[0072] In some examples, the second charging current=the first charging current×the charge correction factor×the cell voltage correction factor.

[0073] In some embodiments, the battery system includes multiple groups of batteries connected in parallel. Figure 2 Step S22 of the illustrated embodiment, determining a second charging correction coefficient of the battery based on the required charging capacity of the battery, may include: obtaining an average value of the required charging capacity based on the required charging capacity of the battery and the number of battery packs connected in parallel to the battery system; obtaining the second charging correction coefficient of the battery based on the required charging capacity of the battery and the average value of the required charging capacity.

[0074] In some embodiments, obtaining a second charging correction coefficient of the battery according to the required charging power of the battery and an average value of the required charging power may include: obtaining the second charging correction coefficient of the battery according to dividing the required charging power of the battery by the average value of the required charging power.

[0075] In a specific implementation, the average charging power required by the battery system = the charging power required by each battery group / the number of parallel battery groups. The second charging correction coefficient of each battery group = the charging power required by the battery group / the average charging power required by the battery system.

[0076] In a specific implementation, for ease of calculation, the second charging correction coefficient of each group of batteries can also be expressed as: the second charging correction coefficient of each group of batteries = the charging power required for the group of batteries / the average charging power required for the battery system×100%.

[0077] In a specific implementation, after the charging current of each battery group is corrected, the charging conditions between the batteries can be comprehensively corrected in combination with the charging conditions between each battery group to ensure that the progress of each battery group from the current power to full charge is basically consistent.

[0078] Specifically, this is achieved by increasing the second charging correction coefficient of the battery with lower power.

[0079] Figure 7 A relationship diagram between a second charging correction coefficient and battery power provided by an embodiment of the present invention. Figure 8 A relationship diagram between a second charging correction coefficient and battery power provided by an embodiment of the present invention. Fig. 9 A diagram showing the relationship between power change and battery power provided in an embodiment of the present invention.

[0080] In some examples, taking charging of two parallel batteries as an example, the power of battery 1 is SOC1, the power correction coefficient is scaleB1, the power of battery 2 is SOC2, the power correction coefficient is scaleB2, and the relationship between the power correction coefficients of battery 1 and battery 2 and the battery power can be as follows: Figure 7 and Figure 8 As shown, the relationship between the charge change △SOC of battery 1 and battery 2 and the battery charge can be expressed as Fig. 9 shown.

[0081] from Figure 7 It can be seen that the battery 1 SOC1 is low, and the second charging correction factor ScaleB1 is 100%. The battery 2 SOC2 is high, and the charging correction factor ScaleB2 is lower than 100%. When the battery 1 and battery 2 SOC1 and SOC2 are close, the second charging correction factor gradually approaches until both are 100%.

[0082] from Figure 8 It can be seen that the battery 1 SOC1 is low, and the second charging correction factor ScaleB1 is 100%. The battery 2 SOC2 is high, and the charging correction factor ScaleB2 is lower than 100%. When the battery 1 and battery 2 SOC1 and SOC2 are close, the second charging correction factor gradually approaches until both are 0.

[0083] from Fig. 9It can be seen that battery 1 has a lower SOC1, charges faster, and has a larger battery change △SOC1; battery 2 has a higher SOC1, charges slower, and has a smaller △SOC2. When the SOC1 and SOC2 of the two batteries are close to full, the charging capacities △SOC1 and △SOC2 of the two branches are close to 0.

[0084] In some embodiments, the present invention Figure 2 In step S23 of the illustrated embodiment, the second charging current of the battery is corrected according to the second charging correction coefficient of the battery to obtain the third charging current of the battery, which may include: comparing the battery power with the third battery power threshold; when the battery power is lower than or equal to the third battery power threshold, correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain the third charging current of the battery. When the battery power is higher than the third battery power threshold, the second charging correction coefficient is configured as a preset value, and the second charging current of the battery is corrected based on the second charging correction coefficient configured as the preset value to obtain the third charging current of the battery.

[0085] In a specific implementation, in order to improve the accuracy of the second charging correction coefficient, after obtaining the second charging correction coefficient, it is also possible to determine whether the battery power is lower than or equal to the third battery power threshold. When the battery power is lower than or equal to the third battery power threshold, the second charging correction coefficient is directly used to correct the second charging current. When the battery power is higher than the third battery power threshold, the second charging correction coefficient is reconfigured, and the second charging current is corrected based on the reconfigured second charging correction coefficient.

[0086] The third battery power threshold value can be set according to the application scenario, for example, any value of 50%, 60%, 70%, 80%, 90%, 95%, etc., but is not limited thereto.

[0087] For example, after calculating the second charging correction coefficient of each group of batteries, it can be determined whether the battery power is greater than 90%. If it is greater than 90%, the second charging correction coefficient is set to 0, that is, there is no need to charge the battery branch. If it does not exceed 90%, the charging current of the corresponding battery is corrected according to the calculated second charging correction coefficient, so that the battery is charged based on the corrected charging current.

[0088] In some embodiments, the second charging correction factor may be limited so that the second charging correction factor cannot exceed a certain value, for example, the second charging correction factor cannot exceed 100%.

[0089] On the other hand, an embodiment of the present invention further provides a battery discharge control method, which can be applied to the battery charge and discharge control system as described above.

[0090] Fig.10 A flow chart of a battery discharge control method provided by an embodiment of the present invention.

[0091] In some embodiments, Fig.10 As shown, the battery discharge control method provided by the embodiment of the present invention may include steps S101 to S104.

[0092] S101: Obtain a first discharge correction coefficient of the battery according to an average available power of the battery system and the available power of each battery group.

[0093] The average available power of the battery system can be obtained by dividing the sum of the available power of each battery group by the number of battery groups connected in parallel in the battery system.

[0094] By dividing the available power of each battery group by the average available power of the battery system, the first discharge correction coefficient of each battery group can be obtained.

[0095] For example, if the battery system has four groups of batteries connected in parallel, the first discharge correction factor of each group of batteries in the battery system can be expressed as: scale_avail_SOCi=SOCi_Avail / ((SOC1_Avail+SOC2_Avail+ SOC3_Avail +SOC4_Avail) / number of parallel battery packs) Wherein, scale_avail_SOCi represents the first discharge correction coefficient of the i-th battery group, i∈[1,4]; SOCi_Avail represents the available power of the i-th battery group.

[0096] In some examples, available battery power=(battery power-battery minimum power) / (battery maximum power-battery minimum power).

[0097] The minimum battery power can be set according to the application scenario of the battery, for example, it can be set to 10% or 15%, etc. The maximum battery power can be set according to the application scenario of the battery, for example, it can be set to 90%.

[0098] For example, Fig.11 A diagram showing the relationship between the available battery power and the battery power provided in an embodiment of the present invention. Fig.11 In the figure, the horizontal axis represents the ratio of available battery power, and the vertical axis represents the ratio of battery power. Fig.11 It can be seen that the available battery power increases as the battery power increases. When the battery power reaches 100%, the available battery power is 90%.

[0099] Calculating the available power of the battery by using the minimum power level and the maximum power level of the battery can avoid battery feeding, which is beneficial to the reliable operation of the battery and increases the battery life.

[0100] S102: Acquire the discharge power of the battery, and obtain a first discharge current of the battery according to the discharge power.

[0101] The method for obtaining the first discharge current is similar to the method for obtaining the first charging current, and will not be described in detail here.

[0102] S103 . Correct the first discharge current of the battery according to the first discharge correction coefficient of the battery to obtain a second discharge current of the battery.

[0103] In a specific implementation, the second discharge current=the first discharge correction coefficient×the first discharge current.

[0104] In one example, during discharge, the battery with high power can be discharged according to the full current value (i.e., 100%), and the battery with low power will reduce the first discharge correction coefficient (lower than 100%), thereby ensuring that each group of batteries can be discharged evenly, improving the discharge consistency between each group of batteries in the battery system, improving the reliability of battery discharge, and increasing the battery life.

[0105] Taking the discharge of a battery system including two parallel batteries as an example, the power of battery 1 is SOC1, the first discharge correction coefficient is scaleB1, the power of battery 2 is SOC2, the first discharge correction coefficient is scaleB2, and the relationship between the second discharge correction coefficient of battery 1 and battery 2 and the battery power can be shown as follows: Fig.12 shown.

[0106] It should be understood that the purpose of the above examples is only to explain the embodiments of the present invention, rather than to limit the embodiments of the present invention.

[0107] S104: Discharge the corresponding battery according to the second discharge current.

[0108] The embodiment of the present invention introduces a first discharge correction coefficient related to the average available power of the battery system and the available power of each group of batteries to correct the discharge current of the battery, thereby ensuring the balance of power between the groups of batteries in the battery system, improving the consistency between the battery groups within the battery system, contributing to the reliable operation of the battery system, and increasing the service life of the battery system.

[0109] In some embodiments, the present invention Fig.10Step S103 of the illustrated embodiment, discharging the corresponding battery according to the second discharge current, may include: calculating the total discharge power of the battery system according to the second discharge current of the battery; and discharging the corresponding battery according to the second discharge current when the total discharge power meets the discharge power requirement value.

[0110] In a specific implementation, the discharge power of each battery group can be obtained according to the second discharge current of each battery group and its corresponding voltage, and the discharge power of each battery group is added together to obtain the total discharge power of the battery system.

[0111] The discharge power requirement value is set according to the actual scenario, and each group of batteries is discharged according to the second discharge current when the total discharge power of the battery system meets the discharge requirement, thereby ensuring the discharge efficiency.

[0112] In some embodiments, the present invention Fig.10 After step S103 of the illustrated embodiment, the battery discharge control method of the embodiment of the present invention may further include: when the total discharge power does not meet the discharge power requirement value, obtaining the discharge power coefficient of the battery according to the discharge power of each group of batteries and the discharge power standard value of the battery, and correcting the second discharge current of the battery according to the discharge power coefficient of the battery and the first discharge correction coefficient of the battery, and discharging the corresponding battery based on the corrected second discharge current.

[0113] In a specific implementation, after obtaining the second discharge current of each battery group, the total discharge power of the battery system can be calculated. If the total discharge power is lower than the discharge power requirement, the discharge current proportionality factor will be increased according to preset conditions until the total discharge power meets the discharge power requirement.

[0114] In a specific implementation, the discharge power coefficient of each group of batteries can be obtained through the discharge power of each group of batteries and the discharge power standard value of the battery.

[0115] In some examples, the discharge power coefficient of each battery group can be obtained by dividing the discharge power of each battery group by its corresponding discharge power standard value, wherein the discharge power standard value can be a discharge power value found in a discharge power table provided by a battery supplier based on the battery power and temperature.

[0116] Table 2 is an exemplary discharge power parameter table.

[0117] Table 2

[0118] In some examples, the discharge power factor ranges from 0 to 100%.

[0119] In a specific implementation, the first discharge correction coefficient of other groups of batteries can be adjusted by the discharge power coefficient of the battery with the highest discharge power coefficient in each group of batteries to obtain the second discharge correction coefficient of other groups of batteries, and the corresponding discharge power of each group of batteries can be corrected by the second discharge correction coefficient.

[0120] In one example, the discharge power coefficient of each battery group is defined as FKWScale_i, where i indicates that the battery system has i groups of batteries connected in parallel, and the battery with the highest discharge power coefficient among the battery groups is the nth battery group connected in parallel, that is, FKWScale_n, and the second discharge correction coefficient ScaleB1' of other battery groups can be expressed as: ScaleB1'=ScaleB1+(100-ScaleB1) / (100-90)×(FKWScale_n-90) Wherein, ScaleB1 is the first discharge correction coefficient of the battery.

[0121] For example, the relationship diagram between the discharge power coefficient of the other groups of batteries except the battery with the highest discharge power coefficient and the second discharge correction coefficient can be as follows: Fig.13 shown.

[0122] For example, the maximum discharge power factor ( Fig.14 Assuming that B100 shown in FIG. 1 is 100%, the relationship diagram of the discharge power coefficient, the second discharge correction coefficient and the highest discharge power coefficient of the battery groups other than the battery with the highest discharge power coefficient can be as follows: Fig.14 shown.

[0123] According to another aspect of the present invention, an embodiment of the present invention further provides a battery charge and discharge control system, including a memory and a processor, wherein the memory stores computer instructions, and the processor executes the battery charge control method as described above by executing the computer instructions, so as to charge and discharge each group of batteries in the battery system respectively. The battery charge and discharge control system of the present invention can keep the power between each group of batteries consistent, improve the consistency between battery groups within the battery system, contribute to the reliable operation of the battery system, and increase the service life of the battery system.

[0124] In some specific implementations, the battery charge and discharge control system includes: a charging current calculation module, configured to obtain a charging power of the battery, and obtain a first charging current of the battery according to the charging power; A first charging correction module, configured to correct a first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery; a charging correction coefficient calculation module, configured to determine a second charging correction coefficient of the battery according to the required charging amount of the battery; a second charging module, configured to correct a second charging current of the battery according to a second charging correction coefficient of the battery to obtain a third charging current of the battery, and charge a corresponding battery based on the third charging current; A discharge correction coefficient calculation module, configured to obtain a first discharge correction coefficient of the battery according to an average available power of the battery system and an available power of each battery group; a discharge current calculation module, configured to obtain a discharge power of the battery, and obtain a first discharge current of the battery according to the discharge power; A first discharge correction module, configured to correct a first discharge current of the battery according to a first discharge correction coefficient of the battery to obtain a second discharge current of the battery; The discharge module is configured to discharge the corresponding battery according to the second discharge current.

[0125] Those skilled in the art can understand that all or part of the processes in the above-mentioned embodiments can be implemented by instructing the relevant hardware through a computer program, and the program can be stored in a computer-readable storage medium. When the program is executed, it can include the processes of the embodiments of the above-mentioned methods. Among them, the storage medium of the program can be a disk, an optical disk, a read-only storage memory (ROM) or a random access memory (RAM), etc. The above-mentioned computer program embodiments can achieve the same or similar effects as the corresponding above-mentioned arbitrary method embodiments.

[0126] It will also be appreciated by those skilled in the art that various exemplary logic blocks, modules, circuits and algorithm steps described in conjunction with the disclosure herein can be implemented as electronic hardware, computer software or a combination of the two. In order to clearly illustrate this interchangeability of hardware and software, a general description has been given to the functions of various schematic components, blocks, modules, circuits and steps. Whether this function is implemented as software or hardware depends on specific applications and the design constraints imposed on the entire system. Those skilled in the art can implement the function in various ways for each specific application, but this implementation decision should not be interpreted as causing a departure from the disclosed scope of the embodiments of the present invention.

[0127] The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope of the embodiments disclosed in the present invention as defined in the claims. The functions, steps and / or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. The serial numbers of the embodiments disclosed in the above embodiments of the present invention are for description only and do not represent the advantages and disadvantages of the embodiments. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.

[0128] It should be understood that, as used herein, the singular forms "a", "an" are intended to include the plural forms as well, unless the context clearly supports an exception. It should also be understood that, as used herein, "and / or" refers to any and all possible combinations including one or more of the associated listed items.

[0129] A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims

1. A battery charging control method, characterized in that: Applied to a battery system comprising at least one group of batteries, the method comprises performing the following steps for each group of batteries: Acquiring a charging power of a battery, and obtaining a first charging current of the battery according to the charging power; Correcting a first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery; Determining a second charging correction coefficient of the battery according to the required charging amount of the battery; The second charging current of the battery is corrected according to the second charging correction coefficient of the battery to obtain a third charging current of the battery, and the current battery group is charged based on the third charging current.

2. The method according to claim 1, characterized in that The step of correcting the first charging current of the battery according to a preconfigured first charging correction coefficient to obtain a second charging current of the battery includes: The first charging correction coefficient and the first charging current are multiplied to obtain a second charging current of the battery.

3. The method according to claim 1, characterized in that The battery system includes a plurality of batteries connected in parallel, and determining the second charging correction coefficient of the battery according to the required charging amount of the battery includes: Obtaining an average value of the required charging power according to the required charging power of the battery and the number of battery groups connected in parallel to the battery system; A second charging correction coefficient of the battery is obtained according to the required charging power of the battery and the average of the required charging power.

4. The method according to claim 3, characterized in that: The obtaining, according to the required charging power of the battery and the average of the required charging power, a second charging correction coefficient of the battery comprises: A second charging correction coefficient of the battery is obtained by dividing the required charging power of the battery by the average required charging power.

5. The method according to claim 1, characterized in that The step of correcting the second charging current of the battery according to the second charging correction coefficient of the battery to obtain a third charging current of the battery includes: comparing the battery power level with a third battery power threshold; When the battery power level is lower than or equal to a third battery power level threshold, the second charging current of the battery is corrected according to the second charging correction coefficient of the battery to obtain a third charging current of the battery.

6. The method according to claim 5, characterized in that The method further comprises: When the battery power level is higher than the third battery power level threshold, the second charging correction coefficient is configured as a preset value, and the second charging current of the battery is corrected based on the second charging correction coefficient configured as the preset value to obtain a third charging current of the battery.

7. The method according to any one of claims 1 to 6, characterized in that: Before obtaining the first charging current of each battery group, the method further includes: The first charging correction coefficient is configured according to the battery power and the single cell voltage, and the first charging correction parameter includes the power correction coefficient and the single cell voltage correction coefficient, wherein: The power correction coefficient is set to a first proportional coefficient when the battery power is lower than a first battery power threshold, and is set to a second proportional coefficient when the battery power is higher than a second battery power threshold, and changes linearly when the battery power is between the first battery power threshold and the second battery power threshold, wherein the first proportional coefficient is greater than the second proportional coefficient; The cell voltage correction coefficient is set to a third proportional coefficient when the cell voltage is lower than a first voltage value, and is set to a fourth proportional coefficient when the cell voltage is higher than a second voltage value, and changes linearly when the cell voltage is between the first voltage value and the second voltage value, wherein the third proportional coefficient is greater than the fourth proportional coefficient.

8. A battery charge and discharge control system, characterized in that: include: A memory and a processor, wherein the memory stores computer instructions, and the processor executes the battery charging control method according to any one of claims 1 to 7 by executing the computer instructions.

9. A battery discharge control method, characterized in that: Applied to the battery charge and discharge control system of claim 8, the method comprising: Obtaining a first discharge correction coefficient of the battery according to an average available power of the battery system and an available power of each group of the batteries; Acquiring a discharge power of the battery, and obtaining a first discharge current of the battery according to the discharge power; Correcting a first discharge current of the battery according to a first discharge correction coefficient of the battery to obtain a second discharge current of the battery; The corresponding battery is discharged according to the second discharge current.

10. The method according to claim 9, characterized in that Discharging the corresponding battery according to the second discharge current includes: Calculating the total discharge power of the battery system according to the second discharge current of the battery; When the total discharge power meets the discharge power requirement value, discharging the corresponding battery according to the second discharge current; When the total discharge power does not meet the discharge power requirement value, the discharge power coefficient of the battery is obtained according to the discharge power of each group of the batteries and the discharge power standard value of the battery, and the second discharge current of the battery is corrected according to the discharge power coefficient of the battery and the first discharge correction coefficient of the battery, and the corresponding battery is discharged based on the corrected second discharge current.

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