An intelligent control method, system and medium for series-parallel connection of forklift lithium battery packs

Abstract

The purpose of the present invention is to provide an intelligent control method, system and medium for series-parallel connection of forklift lithium battery packs, which adjusts the series-parallel state of the lithium battery pack according to the battery mode information of the forklift lithium battery pack; when it is determined that the battery mode information is the power supply output mode, the target voltage information and target current information are determined according to the first control operation instruction; when it is determined that the battery mode information is the charging input mode, the target voltage information and target current information are determined according to the first battery charge information; the series state of the lithium batteries is adjusted according to the target voltage information, and the working current of the lithium battery pack is adjusted in parallel according to the target current information; the series-parallel state of the lithium battery pack is controlled during the power supply process to meet the power supply voltage and power supply current required for forklift work and improve the use efficiency of the lithium battery pack; the series-parallel state of the lithium battery pack is controlled during the charging process to control the charging efficiency and charging safety of the lithium battery pack and extend the service life of the lithium battery.

Description

Technical Field

[0001] The present invention relates to the field of battery power supplies, and more particularly, to an intelligent control method, system, and medium for series-parallel connection of lithium battery packs for forklifts. Background Art

[0002] Lithium batteries for forklifts have a relatively high energy density. Compared with traditional lead-acid batteries, their energy density is approximately twice as high. This means that forklifts can work for a longer time, reducing the need for frequent charging and thus improving work efficiency. Although lithium batteries for forklifts have the characteristics of fast charging and a large number of charge-discharge cycles, there is a lack of an intelligent management system for lithium batteries on the market, and corresponding management measures are taken through the management system to ensure the performance, safety, and service life of the battery pack.

[0003] A lithium battery pack for a forklift is composed of multiple lithium batteries connected in parallel, and a series group of lithium batteries is composed of multiple lithium batteries connected in series. By connecting multiple lithium batteries in series to form a series group, the voltage values of each lithium battery can be superimposed to obtain the voltage value of the series group of lithium batteries. By connecting multiple series groups of lithium batteries in parallel, the current values of each series group of lithium batteries can be superimposed to obtain the current value of the lithium battery pack for the forklift. Through the control of the series-parallel connection of the lithium battery pack for the forklift, the flexibility of use of the lithium battery for the forklift is improved.

[0004] Therefore, there is an urgent need for an intelligent control technology for the series-parallel connection of lithium battery packs for forklifts that can improve the use efficiency and extend the service life of lithium batteries for forklifts. Summary of the Invention

[0005] In view of the above problems, the purpose of the present invention is to provide an intelligent control method, system, and medium for the series-parallel connection of lithium battery packs for forklifts, which adjusts the series-parallel state of the lithium battery pack according to the battery mode information of the lithium battery pack for the forklift; when it is determined that the battery mode information is the power supply output mode, the target voltage information and target current information are determined according to the first control operation instruction; when it is determined that the battery mode information is the charging input mode, the target voltage information and target current information are determined according to the first battery charge information; the series state of the lithium batteries is adjusted according to the target voltage information, and the working current of the lithium battery pack is adjusted in parallel according to the target current information; the series-parallel state of the lithium battery pack is controlled during the power supply process to meet the power supply voltage and power supply current required for forklift work, and the use efficiency of the lithium battery pack is improved; the series-parallel state of the lithium battery pack is controlled during the charging process to control the charging efficiency and charging safety of the lithium battery pack and extend the service life of the lithium battery.

[0006] The first aspect of the present invention provides an intelligent control method for the series-parallel connection of a lithium battery pack for a forklift, and the method includes:

[0007] Obtain battery mode information;

[0008] Determine whether the battery mode information is the power supply output mode;

[0009] If so, obtain the first control operation instruction, and determine the target voltage information and target current information according to the first control operation instruction;

[0010] If not, obtain the first power information, and determine the target voltage information and target current information according to the first power information;

[0011] Adjust the series connection state of the lithium batteries according to the target voltage information;

[0012] Adjust the working current of the lithium battery pack in parallel according to the target current information.

[0013] In this solution, the adjustment of the series connection state of the lithium batteries according to the target voltage information is specifically as follows:

[0014] When it is determined that the battery mode information is the power supply output mode;

[0015] Obtain the first voltage information;

[0016] Obtain the first voltage sequence according to the first voltage information;

[0017] Determine the first lithium battery pack according to the first voltage sequence and the target voltage information;

[0018] Connect the corresponding lithium batteries in series according to the first lithium battery pack.

[0019] In this solution, the adjustment of the series connection state of the lithium batteries according to the target voltage information is specifically as follows:

[0020] When it is determined that the battery mode information is the charging input mode;

[0021] Obtain the second voltage information;

[0022] Obtain the first quantity information according to the second voltage information and the target voltage information;

[0023] Determine the second lithium battery pack according to the first quantity information;

[0024] Connect the corresponding lithium batteries in series according to the second lithium battery pack.

[0025] In this solution, the adjustment of the working current of the lithium battery pack in parallel according to the target current information is specifically as follows:

[0026] Obtain the first temperature information of the lithium battery pack;

[0027] Obtain the first temperature sequence according to the first temperature information;

[0028] Determine first current ratio information according to the first temperature sequence;

[0029] Adjust the working current of the lithium battery pack according to the first current ratio information and the target current information.

[0030] In this solution, obtain a first control operation instruction, and determine target voltage information and target current information according to the first control operation instruction, specifically:

[0031] When it is determined that the battery mode information is the power supply output mode;

[0032] Judge whether it is a first motor control instruction according to the first control operation instruction;

[0033] If so, set the target voltage information according to a preset first output voltage threshold;

[0034] If not, set the target voltage information according to a preset second output voltage threshold;

[0035] Analyze the first control operation instruction to obtain first current information;

[0036] Set the target current information according to the first current information.

[0037] In this solution, obtain first power information, and determine target voltage information and target current information according to the first power information, specifically:

[0038] When it is determined that the battery mode information is the charging input mode;

[0039] Set the target voltage information according to preset first charging voltage information;

[0040] Judge whether the first power information is lower than a preset first power threshold;

[0041] If so, set the target current information according to a set first charging current threshold;

[0042] If not, judge whether the first power information is lower than a preset second power threshold;

[0043] If so, set the target current information according to a set second charging current threshold;

[0044] If not, set the target current information according to a set third charging current threshold.

[0045] The second aspect of the present invention provides an intelligent control system for series-parallel connection of forklift lithium battery packs, including an intelligent control method program for series-parallel connection of forklift lithium battery packs. When the intelligent control method program for series-parallel connection of forklift lithium battery packs is executed by the processor, the following steps are implemented:

[0046] Obtain battery mode information;

[0047] Judge whether the battery mode information is a power supply output mode;

[0048] If so, obtain a first control operation instruction, and determine target voltage information and target current information according to the first control operation instruction;

[0049] If not, obtain first power information, and determine target voltage information and target current information according to the first power information;

[0050] Adjust the series connection state of the lithium batteries according to the target voltage information;

[0051] Adjust the working current of the lithium battery pack in a parallel manner according to the target current information.

[0052] In this solution, the adjustment of the series connection state of the lithium batteries according to the target voltage information is specifically as follows:

[0053] Judge when the battery mode information is a power supply output mode;

[0054] Obtain first voltage information;

[0055] Obtain a first voltage sequence according to the first voltage information;

[0056] Determine a first lithium battery pack according to the first voltage sequence and the target voltage information;

[0057] Connect the corresponding lithium batteries in series according to the first lithium battery pack.

[0058] In this solution, the adjustment of the series connection state of the lithium batteries according to the target voltage information is specifically as follows:

[0059] Judge when the battery mode information is a charging input mode;

[0060] Obtain second voltage information;

[0061] Obtain first quantity information according to the second voltage information and the target voltage information;

[0062] Determine a second lithium battery pack according to the first quantity information;

[0063] Connect the corresponding lithium batteries in series according to the second lithium battery pack.

[0064] In a third aspect of the present invention, a computer-readable storage medium is provided. The computer-readable storage medium includes a program for an intelligent control method of series-parallel connection of a forklift lithium battery pack. When the program for the intelligent control method of series-parallel connection of the forklift lithium battery pack is executed by a processor, the steps of the intelligent control method of series-parallel connection of the forklift lithium battery pack as described in any one of the above are implemented.

[0065] The object of the present invention is to provide an intelligent control method, system and medium for series-parallel connection of a forklift lithium battery pack, which adjusts the series-parallel state of the lithium battery pack according to the battery mode information of the forklift lithium battery pack; when it is determined that the battery mode information is the power supply output mode, the target voltage information and the target current information are determined according to the first control operation instruction; when it is determined that the battery mode information is the charging input mode, the target voltage information and the target current information are determined according to the first battery charge information; the series state of the lithium batteries is adjusted according to the target voltage information, and the working current of the lithium battery pack is adjusted in parallel according to the target current information; the series-parallel state of the lithium battery pack is controlled during the power supply process to meet the power supply voltage and power supply current required for the forklift operation, and the use efficiency of the lithium battery pack is improved; the series-parallel state of the lithium battery pack is controlled during the charging process to control the charging efficiency and charging safety of the lithium battery pack and extend the service life of the lithium battery. BRIEF DESCRIPTION OF THE DRAWINGS

[0066] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required to be used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of the present invention and should not be regarded as limiting the scope.

[0067] Figure 1 Shows a flowchart of an intelligent control method for series-parallel connection of a forklift lithium battery pack according to the present invention;

[0068] Figure 2 Shows a flowchart of adjusting the series state of lithium batteries in the power supply output mode provided by an embodiment of the present invention;

[0069] Figure 3 Shows a flowchart of adjusting the series state of lithium batteries in the charging input mode provided by an embodiment of the present invention;

[0070] Figure 4 Shows a block diagram of an intelligent control system for series-parallel connection of a forklift lithium battery pack according to the present invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0071] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments. All other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without creative efforts belong to the scope of protection of the present invention.

[0072] Unless otherwise defined, all terms (including technical and scientific terms) used in the embodiments of the present invention have the same meaning as commonly understood by those of ordinary skill in the technical field to which the present invention belongs. It should also be understood that terms such as those defined in a general dictionary should be interpreted as having a meaning consistent with their meaning in the context of the relevant art, and should not be interpreted in an idealized or overly formal sense unless explicitly defined in the embodiments of the present invention.

[0073] The "first", "second" and similar terms used in the embodiments of the present invention do not denote any order, quantity or importance, but are only used to distinguish different components. Terms such as "a", "an" or "the" do not denote a limitation of quantity either, but mean that there is at least one. Similarly, words such as "comprising" or "including" mean that the elements or objects appearing before this word cover the elements or objects listed after this word and their equivalents, without excluding other elements or objects. The terms "connected" or "coupled" and the like are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The steps before or after the methods of the embodiments of the present invention do not necessarily have to be carried out precisely in order. On the contrary, they can be carried out in reverse order or simultaneously. At the same time, other operations can also be added to these processes, or one or several steps can be removed from these processes.

[0074] In addition, in each embodiment of the present invention, the functional modules can be integrated together to form an independent part, or each module can exist alone, or two or more modules can be integrated to form an independent part.

[0075] Figure 1 The flowchart of an intelligent control method for series-parallel connection of a forklift lithium battery pack according to the present invention is shown.

[0076] As Figure 1 shown, in a first aspect of the present invention, an intelligent control method for series-parallel connection of a forklift lithium battery pack is disclosed, and the method includes:

[0077] S102, obtaining battery mode information;

[0078] S104, determining whether the battery mode information is a power supply output mode;

[0079] S106. If so, obtain a first control operation instruction, and determine target voltage information and target current information according to the first control operation instruction.

[0080] S108. If not, obtain first power information, and determine target voltage information and target current information according to the first power information.

[0081] S110. Adjust the series connection state of the lithium batteries according to the target voltage information.

[0082] S112. Adjust the working current of the lithium battery pack in a parallel manner according to the target current information.

[0083] It should be noted that the battery mode information is the working mode of the forklift lithium battery pack, including a power supply output mode and a charging input mode. Among them, in the power supply output mode, the lithium battery pack provides electrical energy for the operation and work of the forklift; in the charging input mode, the lithium battery pack accesses the electrical energy supplement of an external power supply. The first control operation instruction is a power supply instruction sent by the forklift to the lithium battery pack system, including but not limited to a power supply instruction for controlling the movement of the forklift wheels and a power supply instruction for controlling the operation of the forklift fork arms. The first power information is the remaining power of the forklift lithium battery pack. The target voltage information is the power supply voltage value or charging voltage value of the forklift lithium battery pack. The target current information is the power supply current value or charging current value of the forklift lithium battery pack.

[0084] In this embodiment, when it is determined that the battery mode information is the power supply output mode, the forklift lithium battery pack provides electrical energy for the work of the forklift. According to the first control operation instruction of the forklift, analyze the target voltage information and target current information required for output. In practical applications, when the forklift needs to drive the wheels to move, the operation of the drive wheel motor is usually in a situation of high voltage and low current; when the forklift needs to drive the fork arms to carry goods, the operation of the drive fork arms is usually in a situation of low voltage and high current. Therefore, by analyzing the first control operation instruction, the target voltage information and target current information are determined; during the power supply process, by controlling the series-parallel connection state of the lithium battery pack, the power supply voltage and power supply current required for the work of the forklift are satisfied, and the use efficiency of the lithium battery pack is improved. When it is determined that the battery mode information is the charging input mode, the external power supply supplements electrical energy to the forklift lithium battery pack. According to the power state of the lithium battery pack, adjust the charging current to control the fast charging working condition of the lithium battery pack. Finally, according to the set target voltage information, adjust the series connection state of the lithium batteries to form a certain number of series groups; then, according to the target current information, set the working current of each series group; during the charging process, by controlling the series-parallel connection state of the lithium battery pack, the charging efficiency and charging safety of the lithium battery pack are controlled, and the service life of the lithium battery is extended.

[0085] Figure 2Shows the adjustment flowchart of the series connection state of lithium batteries in the power supply output mode provided by the embodiments of the present invention.

[0086] According to the embodiments of the present invention, as Figure 2 shown, adjusting the series connection state of lithium batteries according to the target voltage information is specifically as follows:

[0087] S202, when it is determined that the battery mode information is the power supply output mode;

[0088] S204, obtain the first voltage information;

[0089] S206, obtain a first voltage sequence according to the first voltage information;

[0090] S208, determine a first lithium battery pack according to the first voltage sequence and the target voltage information;

[0091] S210, connect the corresponding lithium batteries in series according to the first lithium battery pack.

[0092] It should be noted that the first voltage information is the voltage value of each lithium battery; the first voltage sequence is a sequence obtained by arranging all the lithium battery voltage values in ascending or descending order; the first lithium battery pack is a series combination of lithium batteries in which one of the voltage values reaches the target voltage information. In this embodiment, according to the voltage values of each lithium battery, they are combined in a set manner so that the first lithium battery pack formed by series connection after combination can reach the target voltage information. As an implementation manner, the combination method of lithium batteries is to combine according to the maximum value of the first voltage sequence and several voltage values in the first voltage sequence, and select the minimum value exceeding the target voltage information in the combination as the first lithium battery pack.

[0093] Figure 3 Shows the adjustment flowchart of the series connection state of lithium batteries in the charging input mode provided by the embodiments of the present invention.

[0094] According to the embodiments of the present invention, as Figure 3 shown, adjusting the series connection state of lithium batteries according to the target voltage information is specifically as follows:

[0095] S302, when it is determined that the battery mode information is the charging input mode;

[0096] S304, obtain the second voltage information;

[0097] S306, obtain a first quantity information according to the second voltage information and the target voltage information;

[0098] S308, determine a second lithium battery pack according to the first quantity information;

[0099] S310. Connect the corresponding lithium batteries in series according to the second lithium battery pack.

[0100] It should be noted that the second voltage information is the default voltage value when the lithium battery is charged; the first quantity information is the number of lithium batteries in the series group; the second lithium battery pack is a series combination of lithium batteries during one of the charging processes. In this embodiment, according to the default charging voltage of each lithium battery and the set target voltage information, the first quantity information is calculated to connect the corresponding number of lithium batteries in series to form the second lithium battery pack. By connecting different numbers of lithium batteries in series during charging, different charging voltages can be adapted, improving the flexibility of the charging working state.

[0101] According to an embodiment of the present invention, adjusting the working current of the lithium battery pack in parallel according to the target current information is specifically as follows:

[0102] Obtain the first temperature information of the lithium battery pack;

[0103] According to the first temperature information, obtain the first temperature sequence;

[0104] According to the first temperature sequence, determine the first current ratio information;

[0105] Adjust the working current of the lithium battery pack according to the first current ratio information and the target current information.

[0106] It should be noted that the first temperature information is the temperature value of each lithium battery pack; the first temperature sequence is the temperature sequence obtained by arranging the temperature values of all lithium battery packs in ascending or descending order; the first current ratio information is the current ratio of the power supply output or the current ratio of the charging input of each lithium battery pack. During the charging or discharging process of the lithium battery, the greater the working current of the lithium battery pack, the higher its heat generation. In this embodiment, in order to ensure that the temperature values of each lithium battery pack tend to be the same, the corresponding current ratio is set according to the temperature value of the lithium battery pack. That is to say, the higher the temperature value of the lithium battery pack, the lower the current required for its output or input. As an implementation method, calculate the temperature difference between the temperature value of the lithium battery pack and the standard working temperature of the lithium battery pack, and determine the current ratio according to the temperature difference of each lithium battery pack. Finally, according to the current ratio and the target current information, the working current of the lithium battery pack can be obtained.

[0107] According to an embodiment of the present invention, obtain the first control operation instruction, and determine the target voltage information and the target current information according to the first control operation instruction, specifically as follows:

[0108] When it is determined that the battery mode information is the power supply output mode;

[0109] Judge whether it is the first motor control instruction according to the first control operation instruction;

[0110] If so, set the target voltage information according to the preset first output voltage threshold;

[0111] If not, set the target voltage information according to the preset second output voltage threshold;

[0112] Analyze the first control operation instruction to obtain the first current information;

[0113] Set the target current information according to the first current information.

[0114] It should be noted that the first control operation instruction includes, but is not limited to, the power supply instruction for controlling the movement of the forklift wheels and the power supply instruction for controlling the operation of the forklift fork arms. When it is determined that the first control operation instruction is the first motor control instruction, that is, the power supply instruction for controlling the movement of the forklift wheels, the target voltage information is set according to the working voltage set for the wheels, that is, the first output voltage threshold. Then, as an implementation manner, the first current information is obtained by analyzing the current value required for the running speed of the wheels in the first control operation instruction, and is used to set the target current information. When it is determined that the first control operation instruction is the power supply instruction for the operation of the forklift fork arms, the target voltage information is set according to the working voltage set for the fork arms, that is, the second output voltage threshold. Then, as an implementation manner, the current value calculated according to the working state of the fork arms, including factors such as the movement direction of the fork arms and the weight of the carried goods, in the first control operation instruction is used to set the target current information.

[0115] According to the embodiment of the present invention, the first power information is obtained, and according to the first power information, the target voltage information and the target current information are determined, specifically:

[0116] Judge when the battery mode information is the charging input mode;

[0117] Set the target voltage information according to the preset first charging voltage information;

[0118] Judge whether the first power information is lower than the preset first power threshold;

[0119] If so, set the target current information according to the set first charging current threshold;

[0120] If not, judge whether the first power information is lower than the preset second power threshold;

[0121] If so, set the target current information according to the set second charging current threshold;

[0122] If not, set the target current information according to the set third charging current threshold.

[0123] It should be noted that in this embodiment, according to the power value of the forklift lithium battery pack, the charging working modes are set, including the fast charging mode, the standard charging mode, and the trickle charging mode. When the first power information is lower than the preset first power threshold, it indicates that the power of the forklift lithium battery pack is at a low level, and the electric energy should be quickly supplemented through the fast charging mode; therefore, the target current information is set according to the set first charging current threshold, and a high current method is adopted to increase the charging speed. When the first power information is higher than the preset first power threshold and lower than the preset second power threshold, it indicates that the power of the forklift lithium battery pack has reached the set working requirement level. To avoid problems such as overheating or overcharging caused by continuous fast charging, the target current information is set according to the set second charging current threshold, and the charging is carried out with a standard current value. When the first power information is higher than the preset second power threshold, it indicates that the power of the forklift lithium battery pack is sufficient, and the trickle slow charging method can be adopted to avoid overcharging of the lithium battery, so as to extend the service life of the lithium battery.

[0124] It is worth mentioning that it also includes:

[0125] When it is determined that the battery mode information is the charging input mode;

[0126] Obtain the first temperature information and the second current information of the lithium battery pack;

[0127] According to the first temperature information, determine the first current upper limit threshold;

[0128] Judge whether the set second current information exceeds the preset first current upper limit threshold;

[0129] If so, adjust the target voltage information and the target current information according to the first current upper limit threshold.

[0130] It should be noted that the second current information is the charging current of any lithium battery pack. When it is determined that the battery mode information is the charging input mode, according to the temperature value of the lithium battery pack, determine the charging current upper limit value of the lithium battery pack, that is, the first current upper limit threshold; used to limit the continuous heating of the lithium battery due to excessive current and reduce the risk of damage to the lithium battery core due to overheating. When the second current information exceeds the first current upper limit threshold, it indicates that there is a risk of continuous heating and temperature rise. At this time, the target charging voltage and target charging current of the forklift lithium battery pack are readjusted according to the first current upper limit threshold to ensure the safety of charging.

[0131] It is worth mentioning that it also includes:

[0132] When the battery mode information is the power supply output mode

[0133] When it is determined to be a second motor control instruction according to the first control operation instruction;

[0134] Obtain the first power information;

[0135] Judge whether the first power information is lower than a preset fourth power threshold;

[0136] If so, set the target voltage information according to a preset second output voltage threshold;

[0137] Adjust the series connection state of all lithium batteries according to the target voltage information.

[0138] It should be noted that the second motor control instruction is a power supply instruction for the forklift fork arm to work. In actual applications, a relatively large supply current is usually required during the process of the fork arm carrying goods. Therefore, to ensure the continuity of current supply and avoid the fork arm losing force due to insufficient power, in this embodiment, by judging whether the first power information is lower than a preset fourth power threshold, if so, it means that the power of the forklift lithium battery pack is at the set critical level. At this time, all lithium batteries are connected in series in the battery pack according to the target voltage information to form the series group with the largest number, and each series group is connected in parallel to ensure that the supply current meets the working requirements of the fork arm.

[0139] It is worth mentioning that it also includes:

[0140] Obtain the charging record information;

[0141] Obtain the first charging ratio information according to the charging record information;

[0142] Judge whether the first charging ratio information exceeds a preset first charging ratio threshold;

[0143] If so, increase the first charging current threshold;

[0144] If not, judge whether the first charging ratio information is lower than a preset second charging ratio threshold;

[0145] If so, decrease the first charging current threshold.

[0146] It should be noted that in this embodiment, according to the charging record, the ratio of the charging power to the charging duration is calculated to obtain the first charging ratio information, which is used to represent the user's charging habit. A high first charging ratio information indicates that the user is accustomed to supplementing a large amount of electric energy in a short time. When the first charging ratio information exceeds the preset first charging ratio threshold, it indicates that the user's short-time charging demand is high. Therefore, by increasing the first charging current threshold, that is, increasing the charging current in the fast charging mode, the charging speed is increased. When the first charging ratio information is lower than the preset second charging ratio threshold, it indicates that the user is accustomed to long-time charging. To reduce the impact of rapid energy replenishment on the battery cells, the charging current in the fast charging mode is reduced to increase the service life of the lithium battery.

[0147] Figure 4 The block diagram of an intelligent control system for series-parallel connection of a forklift lithium battery pack according to the present invention is shown.

[0148] As Figure 4 shown, a second aspect of the present invention discloses an intelligent control system 4 for series-parallel connection of a forklift lithium battery pack, including a memory 41 and a processor 42. The memory includes an intelligent control method program for series-parallel connection of a forklift lithium battery pack. When the intelligent control method program for series-parallel connection of a forklift lithium battery pack is executed by the processor, the following steps are implemented:

[0149] Obtain battery mode information;

[0150] Determine whether the battery mode information is a power supply output mode;

[0151] If so, obtain a first control operation instruction, and determine target voltage information and target current information according to the first control operation instruction;

[0152] If not, obtain first power information, and determine target voltage information and target current information according to the first power information;

[0153] Adjust the series state of the lithium battery according to the target voltage information;

[0154] Adjust the working current of the lithium battery pack in a parallel manner according to the target current information.

[0155] It should be noted that the battery mode information is the working mode of the forklift lithium battery pack, including the power supply output mode and the charging input mode. Among them, in the power supply output mode, the lithium battery pack provides electrical energy for the operation and work of the forklift; in the charging input mode, the lithium battery pack accesses the electrical energy supplement of the external power supply. The first control operation instruction is a power supply instruction sent by the forklift to the lithium battery pack system, including but not limited to the power supply instruction for controlling the movement of the forklift wheels and the power supply instruction for controlling the operation of the forklift fork arms. The first power quantity information is the remaining power of the forklift lithium battery pack. The target voltage information is the power supply voltage value or the charging voltage value of the forklift lithium battery pack. The target current information is the power supply current value or the charging current value of the forklift lithium battery pack.

[0156] In this embodiment, when it is determined that the battery mode information is the power supply output mode, the forklift lithium battery pack provides electrical energy for the work of the forklift. According to the first control operation instruction of the forklift, the target voltage information and the target current information required for output are analyzed. In practical applications, when the forklift needs to drive the wheels to move, the operation of the drive wheel motor is usually in the case of high voltage and low current; when the forklift needs to drive the fork arms to carry goods, the operation of the drive fork arms is usually in the case of low voltage and high current. Therefore, by analyzing the first control operation instruction, the target voltage information and the target current information are determined; during the power supply process, by controlling the series-parallel state of the lithium battery pack, the power supply voltage and the power supply current required for the work of the forklift are satisfied, and the use efficiency of the lithium battery pack is improved. When it is determined that the battery mode information is the charging input mode, the external power supply supplements electrical energy for the forklift lithium battery pack. According to the power quantity state of the lithium battery pack, the charging current is adjusted to control the fast charging working condition of the lithium battery pack. Finally, according to the set target voltage information, the series connection state of the lithium batteries is adjusted to form a certain number of series groups; then according to the target current information, the working current of each series group is set; during the charging process, by controlling the series-parallel state of the lithium battery pack, the charging efficiency and the charging safety of the lithium battery pack are controlled, and the service life of the lithium battery is extended.

[0157] According to the embodiment of the present invention, the adjustment of the series state of the lithium batteries according to the target voltage information is specifically as follows:

[0158] When it is determined that the battery mode information is the power supply output mode;

[0159] Obtain the first voltage information;

[0160] According to the first voltage information, obtain the first voltage sequence;

[0161] According to the first voltage sequence and the target voltage information, determine the first lithium battery pack;

[0162] Connect the corresponding lithium batteries in series according to the first lithium battery pack.

[0163] It should be noted that the first voltage information is the voltage value of each lithium battery; the first voltage sequence is a sequence obtained by arranging all the lithium battery voltage values in ascending or descending order; the first lithium battery pack is a series combination of lithium batteries in which one of the voltage values reaches the target voltage information. In this embodiment, according to the voltage values of each lithium battery, they are combined in a set manner so that the first lithium battery pack formed by series connection after combination can reach the target voltage information. As an implementation manner, the combination method of lithium batteries is to combine according to the maximum value of the first voltage sequence and several voltage values in the first voltage sequence, and select the minimum value exceeding the target voltage information in the combination as the first lithium battery pack.

[0164] According to an embodiment of the present invention, the adjustment of the series state of lithium batteries according to the target voltage information is specifically as follows:

[0165] When it is determined that the battery mode information is the charging input mode;

[0166] Obtain the second voltage information;

[0167] According to the second voltage information and the target voltage information, obtain the first quantity information;

[0168] Determine the second lithium battery pack according to the first quantity information;

[0169] Connect the corresponding lithium batteries in series according to the second lithium battery pack.

[0170] It should be noted that the second voltage information is the default voltage value during lithium battery charging; the first quantity information is the number of lithium batteries in the series group; the second lithium battery pack is a series combination of lithium batteries during charging. In this embodiment, according to the default charging voltage of each lithium battery and the set target voltage information, the first quantity information is calculated to connect the corresponding number of lithium batteries in series to form the second lithium battery pack. By connecting different numbers of lithium batteries in series during charging, different charging voltages can be adapted, improving the flexibility of the charging working state.

[0171] According to an embodiment of the present invention, the adjustment of the working current of the lithium battery pack in parallel according to the target current information is specifically as follows:

[0172] Obtain the first temperature information of the lithium battery pack;

[0173] According to the first temperature information, obtain the first temperature sequence;

[0174] Determine the first current ratio information according to the first temperature sequence;

[0175] Adjust the working current of the lithium battery pack according to the first current ratio information and the target current information.

[0176] It should be noted that the first temperature information is the temperature value of each lithium battery pack; the first temperature sequence is the temperature sequence obtained by arranging the temperature values of all lithium battery packs in ascending or descending order; the first current ratio information is the current ratio of the power supply output or the current ratio of the charging input of each lithium battery pack. During the charging or discharging process of the lithium battery, the greater the working current of the lithium battery pack, the higher its heat generation. In this embodiment, in order to ensure that the temperature values of each lithium battery pack tend to be the same, the corresponding current ratio is set according to the temperature value of the lithium battery pack. That is to say, the higher the temperature value of the lithium battery pack, the lower the current required for its output or input. As an implementation method, calculate the temperature difference between the temperature value of the lithium battery pack and the standard working temperature of the lithium battery pack, and determine the current ratio according to the temperature difference of each lithium battery pack. Finally, according to the current ratio and the target current information, the working current of the lithium battery pack can be obtained.

[0177] According to the embodiment of the present invention, the first control operation instruction is obtained, and according to the first control operation instruction, the target voltage information and the target current information are determined, specifically:

[0178] When it is determined that the battery mode information is the power supply output mode;

[0179] According to the first control operation instruction, determine whether it is the first motor control instruction;

[0180] If so, set the target voltage information according to the preset first output voltage threshold;

[0181] If not, set the target voltage information according to the preset second output voltage threshold;

[0182] Analyze the first control operation instruction to obtain the first current information;

[0183] Set the target current information according to the first current information.

[0184] It should be noted that the first control operation instruction includes, but is not limited to, a power supply instruction for controlling the movement of the forklift wheels and a power supply instruction for controlling the operation of the forklift fork arms. When it is determined that the first control operation instruction is the first motor control instruction, that is, the power supply instruction for controlling the movement of the forklift wheels, the target voltage information is set according to the working voltage set for the wheels, that is, the first output voltage threshold. Then, as an implementation manner, the first current information is obtained by parsing the current value required for the wheel running speed in the first control operation instruction, and is used to set the target current information. When it is determined that the first control operation instruction is the power supply instruction for the operation of the forklift fork arms, the target voltage information is set according to the working voltage set for the fork arms, that is, the second output voltage threshold. Then, as an implementation manner, the current value calculated by parsing the first control operation instruction for the working state of the fork arms, including factors such as the movement direction of the fork arms and the weight of the transported goods, is used to set the target current information.

[0185] According to an embodiment of the present invention, the first power quantity information is obtained, and the target voltage information and the target current information are determined according to the first power quantity information, specifically:

[0186] When it is determined that the battery mode information is the charging input mode;

[0187] The target voltage information is set according to the preset first charging voltage information;

[0188] It is determined whether the first power quantity information is lower than a preset first power quantity threshold;

[0189] If so, the target current information is set according to the set first charging current threshold;

[0190] If not, it is determined whether the first power quantity information is lower than a preset second power quantity threshold;

[0191] If so, the target current information is set according to the set second charging current threshold;

[0192] If not, the target current information is set according to the set third charging current threshold.

[0193] It should be noted that in this embodiment, the charging working mode is set according to the power value of the forklift lithium battery pack, including the fast charging mode, the standard charging mode, and the trickle charging mode. When the first power information is lower than the preset first power threshold, it indicates that the power of the forklift lithium battery pack is at a low level, and electric energy should be quickly supplemented through the fast charging mode; therefore, the target current information is set according to the set first charging current threshold, and a high current is used to increase the charging speed. When the first power information is higher than the preset first power threshold and lower than the preset second power threshold, it indicates that the power of the forklift lithium battery pack has reached the set working requirement level. To avoid problems such as heating or overcharging caused by continuous fast charging, the target current information is set according to the set second charging current threshold, and a standard current value is used for charging. When the first power information is higher than the preset second power threshold, it indicates that the power of the forklift lithium battery pack is sufficient, and the trickle slow charging method can be used to avoid overcharging of the lithium battery and extend the service life of the lithium battery.

[0194] It is worth mentioning that it also includes:

[0195] When it is determined that the battery mode information is the charging input mode;

[0196] Obtain the first temperature information and the second current information of the lithium battery pack;

[0197] Determine the first current upper limit threshold according to the first temperature information;

[0198] Judge whether the set second current information exceeds the preset first current upper limit threshold;

[0199] If so, adjust the target voltage information and the target current information according to the first current upper limit threshold.

[0200] It should be noted that the second current information is the charging current of any lithium battery pack. When it is determined that the battery mode information is the charging input mode, the charging current upper limit value of the lithium battery pack, that is, the first current upper limit threshold, is determined according to the temperature value of the lithium battery pack; this is used to limit the continuous heating of the lithium battery due to excessive current and reduce the risk of damage to the lithium battery core due to overheating. When the second current information exceeds the first current upper limit threshold, it indicates that there is a risk of continuous heating and temperature rise. At this time, the target charging voltage and target charging current of the forklift lithium battery pack are readjusted according to the first current upper limit threshold to ensure the safety of charging.

[0201] It is worth mentioning that it also includes:

[0202] When the battery mode information is the power supply output mode

[0203] When it is determined according to the first control operation instruction that it is the second motor control instruction;

[0204] Obtain the first power information;

[0205] Determine whether the first power information is lower than a preset fourth power threshold;

[0206] If so, set the target voltage information according to a preset second output voltage threshold;

[0207] Adjust the series connection state of all lithium batteries according to the target voltage information.

[0208] It should be noted that the second motor control instruction is a power supply instruction for the forklift fork arm to work. In practical applications, a relatively large supply current is usually required during the process of the fork arm carrying goods. Therefore, to ensure the continuity of the current supply and avoid the fork arm losing force due to insufficient power, in this embodiment, by determining whether the first power information is lower than a preset fourth power threshold, if so, it means that the power of the forklift lithium battery pack is at the set critical level. At this time, all lithium batteries are connected in series in the battery pack according to the target voltage information to form the series group with the largest number, and each series group is connected in parallel to ensure that the supply current meets the working requirements of the fork arm.

[0209] It is worth mentioning that it further includes:

[0210] Obtain the charging record information;

[0211] Obtain the first charging ratio information according to the charging record information;

[0212] Determine whether the first charging ratio information exceeds a preset first charging ratio threshold;

[0213] If so, increase the first charging current threshold;

[0214] If not, determine whether the first charging ratio information is lower than a preset second charging ratio threshold;

[0215] If so, decrease the first charging current threshold.

[0216] It should be noted that in this embodiment, according to the charging record, the ratio of the charging power to the charging duration is calculated to obtain the first charging ratio information, which is used to represent the user's charging habit. A high first charging ratio information indicates that the user is accustomed to supplementing a large amount of electric energy in a short time. When the first charging ratio information exceeds the preset first charging ratio threshold, it means that the user's short-time charging demand is relatively high. Therefore, by increasing the first charging current threshold, that is, increasing the charging current in the fast charging mode, the charging speed is improved. When the first charging ratio information is lower than the preset second charging ratio threshold, it means that the user is accustomed to long-time charging. To reduce the impact on the battery cells caused by rapid energy replenishment, the charging current in the fast charging mode is reduced to improve the service life of the lithium battery.

[0217] In a third aspect of the present invention, a computer-readable storage medium is provided. The computer-readable storage medium includes a program for an intelligent control method of series-parallel connection of a forklift lithium battery pack. When the program for the intelligent control method of series-parallel connection of the forklift lithium battery pack is executed by a processor, the steps of the intelligent control method of series-parallel connection of the forklift lithium battery pack as described in any one of the above are implemented.

[0218] The object of the present invention is to provide an intelligent control method, system and medium for series-parallel connection of a forklift lithium battery pack, adjust the series-parallel state of the lithium battery pack according to the battery mode information of the forklift lithium battery pack; when it is determined that the battery mode information is a power supply output mode, determine the target voltage information and target current information according to the first control operation instruction; when it is determined that the battery mode information is a charging input mode, determine the target voltage information and target current information according to the first battery charge information; adjust the lithium battery series state according to the target voltage information, and adjust the working current of the lithium battery pack in a parallel manner according to the target current information; realize controlling the series-parallel state of the lithium battery pack during the power supply process to meet the power supply voltage and power supply current required for forklift operation and improve the use efficiency of the lithium battery pack; realize controlling the series-parallel state of the lithium battery pack during the charging process to control the charging efficiency and charging safety of the lithium battery pack and extend the service life of the lithium battery.

[0219] If the above functions are implemented in the form of software function modules and sold or used as independent products, they can be stored in a computer-readable storage medium. Based on such an understanding, the technical solution of the present invention, in essence, or the part that makes a contribution to the prior art, or a part of the technical solution, can be embodied in the form of a software product. The computer software product is stored in a storage medium and includes several instructions for causing a computer device (which may be a personal computer, a server, or a network device, etc.) to execute all or part of the steps of the methods described in various embodiments of the present invention. The aforementioned storage medium includes: various media such as USB flash drives, mobile hard disks, read-only memories (ROM, Read-Only Memory), random access memories (RAM, Random Access Memory), magnetic disks or optical discs that can store program codes.

[0220] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An intelligent control method for series-parallel connection of lithium battery packs for forklifts, characterized in that: The method comprises: Get battery mode information; Determining whether the battery mode information is a power supply output mode; If yes, obtaining a first control operation instruction, and determining target voltage information and target current information according to the first control operation instruction; If not, obtaining first power information, and determining target voltage information and target current information according to the first power information; When it is determined that the battery mode information is a power supply output mode; Acquiring first voltage information; Obtaining a first voltage sequence according to the first voltage information; Determining a first lithium battery group according to the first voltage sequence and the target voltage information; Connecting corresponding lithium batteries in series according to the first lithium battery group; When it is determined that the battery mode information is a charging input mode; Acquiring second voltage information; Obtaining first quantity information according to the second voltage information and the target voltage information; Determining a second lithium battery pack according to the first quantity information; Connecting corresponding lithium batteries in series according to the second lithium battery group; Acquire first temperature information of the lithium battery pack; Obtaining a first temperature sequence according to the first temperature information; Determining first current ratio information according to the first temperature sequence; The operating current of the lithium battery pack is adjusted according to the first current ratio information and the target current information.

2. The intelligent control method for series-parallel connection of forklift lithium battery packs according to claim 1, characterized in that: The first control operation instruction is obtained, and the target voltage information and the target current information are determined according to the first control operation instruction, specifically: When it is determined that the battery mode information is a power supply output mode; According to the first control operation instruction, determining whether it is a first motor control instruction; If yes, setting the target voltage information according to the preset first output voltage threshold; If not, setting the target voltage information according to a preset second output voltage threshold; parsing the first control operation instruction to obtain first current information; The target current information is set according to the first current information.

3. The intelligent control method for series-parallel connection of forklift lithium battery packs according to claim 1, characterized in that: The first power information is obtained, and the target voltage information and the target current information are determined according to the first power information, specifically: When it is determined that the battery mode information is a charging input mode; Setting target voltage information according to preset first charging voltage information; Determining whether the first power information is lower than a preset first power threshold; If yes, setting the target current information according to the set first charging current threshold; If not, determining whether the first power information is lower than a preset second power threshold; If yes, setting the target current information according to the set second charging current threshold; If not, the target current information is set according to the set third charging current threshold.

4. An intelligent control system for series-parallel connection of lithium battery packs for forklifts, characterized in that: The system includes a memory and a processor, wherein the memory includes an intelligent control method program for connecting a forklift lithium battery pack in series and parallel, and when the intelligent control method program for connecting a forklift lithium battery pack in series and parallel is executed by the processor, the following steps are implemented: Get battery mode information; Determining whether the battery mode information is a power supply output mode; If yes, obtaining a first control operation instruction, and determining target voltage information and target current information according to the first control operation instruction; If not, obtaining first power information, and determining target voltage information and target current information according to the first power information; When it is determined that the battery mode information is a power supply output mode; Acquiring first voltage information; Obtaining a first voltage sequence according to the first voltage information; Determining a first lithium battery group according to the first voltage sequence and the target voltage information; Connecting corresponding lithium batteries in series according to the first lithium battery group; When it is determined that the battery mode information is a charging input mode; Acquiring second voltage information; Obtaining first quantity information according to the second voltage information and the target voltage information; Determining a second lithium battery pack according to the first quantity information; Connecting corresponding lithium batteries in series according to the second lithium battery group; Acquire first temperature information of the lithium battery pack; Obtaining a first temperature sequence according to the first temperature information; Determining first current ratio information according to the first temperature sequence; The operating current of the lithium battery pack is adjusted according to the first current ratio information and the target current information.

5. A computer-readable storage medium having a computer program stored thereon, characterized in that: The computer-readable storage medium includes a program for an intelligent control method for series-parallel connection of a forklift lithium battery pack. When the program for the intelligent control method for series-parallel connection of a forklift lithium battery pack is executed by a processor, the steps of the intelligent control method for series-parallel connection of a forklift lithium battery pack as described in any one of claims 1 to 3 are implemented.

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