BMS management system for AGV

Abstract

The invention discloses a BMS (Battery Management System) for an AGV (Automatic Guided Vehicle), and relates to the technical field of automatic guided vehicles. The system comprises a charging power supply input end, an AGV driving load, a battery pack, an AGV starting circuit, an AGV central control system and a battery protection board. A driving control circuit board of the battery protection board is provided with a main control circuit, and a power circuit board is provided with a switch array circuit. The main control circuit can correspondingly control the work of the switch array circuit according to a discharge control signal output by the AGV central control system so as to control whether the battery pack supplies power to the AGV driving load or not. The main control circuit also can correspondingly control the operation of the switch array circuit according to whether the voltage of the input end of the charging power supply exceeds a preset voltage threshold value so as to control whether to charge the battery pack. According to the invention, power supply separation of the starting circuit of the AGV and the driving load of the AGV is realized, circuit board separation of the driving control circuit board and the power circuit board is realized, and parallel operation power supply of the battery pack is facilitated.

Description

Technical Field

[0001] The present invention relates to the technical field of automatic guided vehicles, and in particular to a BMS management system for AGVs. Background Art

[0002] With the continuous improvement of industrial automation, Automated Guided Vehicles (AGV) are playing an increasingly important role in modern manufacturing and logistics industries due to their high efficiency and accuracy. The normal operation of AGV depends largely on its battery management system (BMS), which is responsible for monitoring the health status of the battery and ensuring safe charging and discharging.

[0003] The BMS management system used by existing AGVs is mainly composed of a single circuit board, which integrates functional modules such as battery status monitoring, balancing management, and safety protection. However, the centralized signal processing of a single circuit board easily leads to increased electromagnetic interference, affecting the stability of the system. Moreover, the design of a single circuit board limits the scalability of the system and is not conducive to the parallel power supply of multiple battery packs. Summary of the invention

[0004] The main purpose of the present invention is to provide a BMS management system for AGV, aiming to solve the problem that the existing BMS management system of AGV is easily affected by electromagnetic interference and lacks an effective expansion mechanism.

[0005] To achieve the above purpose, the AGV BMS management system proposed in the present invention includes:

[0006] Charging power input terminal;

[0007] AGV drives the load;

[0008] Battery pack;

[0009] An AGV start-up circuit, the AGV start-up circuit being electrically connected to the first power supply terminal of the battery pack; the AGV start-up circuit being used to connect / disconnect the power supply connection of the battery pack when triggered by a user;

[0010] An AGV central control system, the AGV central control system being electrically connected to the AGV starting circuit; the AGV central control system being configured to output a corresponding discharge control signal when triggered by a user;

[0011] The battery protection board comprises a drive control circuit board and a power circuit board, wherein a first interface of the drive control circuit board is electrically connected to a second interface of the power circuit board;

[0012] A switch array circuit is arranged on the drive control circuit board; the switch array circuit is electrically connected to the charging power input terminal, the power terminal of the AGV driving load, and the second power terminal of the battery pack respectively; the switch array circuit is used to control the conduction / disconnection of the circuit between the battery pack and the charging power input terminal, and to control the conduction / disconnection of the circuit between the battery pack and the AGV driving load;

[0013] A main control circuit is arranged on the power circuit board; the main control circuit is electrically connected to the third power supply terminal of the battery pack, the controlled end of the switch array circuit, the control end of the AGV central control system, and the detection end of the charging power input end respectively;

[0014] The main control circuit is used to output a corresponding first drive control signal according to the discharge control signal to drive the operation of the switch array circuit to control the discharge of the battery pack to the AGV drive load; and is used to output a corresponding second drive control signal according to the voltage value of the charging power input terminal to drive the operation of the switch array circuit to control the charging of the battery pack.

[0015] In one embodiment, the main control circuit includes:

[0016] An analog front-end circuit is arranged on the drive control circuit board; the analog front-end circuit is electrically connected to the battery pack, the switch array circuit, and the charging power input terminal respectively;

[0017] Wherein, the analog front-end circuit comprises:

[0018] A charge and discharge drive control module, used for outputting the first drive control signal / the second drive control signal to drive the switch array circuit to operate;

[0019] A voltage acquisition module, used for acquiring the battery voltage of the battery pack and outputting a corresponding battery voltage signal to the control circuit;

[0020] A charging detection module, used to collect the voltage at the input end of the charging power supply and output a corresponding charging control signal;

[0021] The main control circuit also includes:

[0022] A main controller is arranged on the drive control circuit board; the main controller is electrically connected to the third power supply terminal of the battery pack, the interactive terminal of the analog front-end circuit, and the control terminal of the AGV central control system respectively;

[0023] The main controller is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the operation of the switch array circuit according to the discharge control signal and the battery voltage signal; and is used to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the operation of the switch array circuit according to the charge control signal and the battery voltage signal.

[0024] In one embodiment, the AGV BMS management system further includes:

[0025] A current sampling resistor is arranged on the power circuit board, one end of the current sampling resistor is electrically connected to the battery pack, the other end of the current sampling resistor is electrically connected to the switch array circuit, and the output end of the current sampling resistor is electrically connected to the analog front-end circuit;

[0026] The analog front end circuit also includes:

[0027] A current detection module, the current detection module is used to detect the current flowing through the current sampling resistor and output a corresponding current detection signal;

[0028] The main controller is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the switch array circuit to disconnect the battery pack from the AGV drive load when it is determined according to the current detection signal that the discharge current of the battery pack exceeds a preset current range; and to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the switch array circuit to disconnect the battery pack from the charging power input terminal when it is determined according to the current detection signal that the charging current of the battery pack exceeds a preset current range.

[0029] In one embodiment, the battery pack includes a plurality of battery cells, and the voltage acquisition module is further used to acquire battery voltages of the plurality of battery cells; the AGV BMS management system further includes:

[0030] A voltage balancing circuit is arranged on the driving control circuit board, and the voltage balancing circuit is electrically connected to the analog front-end circuit and the plurality of battery cells respectively; the voltage balancing circuit is used to balance the battery voltages of the plurality of battery cells of the battery pack;

[0031] The analog front end circuit also includes:

[0032] A voltage balancing control module, used for outputting a third driving control signal to drive the voltage balancing circuit to work;

[0033] The main controller is used to control the voltage balancing control module to output a corresponding third driving control signal to drive the voltage balancing circuit to work when it is determined that the battery voltages of the multiple battery cells are unbalanced according to the battery voltages of the multiple battery cells.

[0034] In one embodiment, the main controller includes a temperature collection port, and the temperature collection port is arranged close to the battery pack; the main controller is also used to collect the ambient temperature of the battery pack and operate according to the ambient temperature of the battery pack.

[0035] In one embodiment, the AGV BMS management system further includes:

[0036] A pre-charging circuit is arranged on the power circuit board, wherein the input end of the pre-charging circuit is electrically connected to the charging power input end; the output end of the pre-charging circuit is electrically connected to the other end of the current sampling circuit; the controlled end of the pre-charging circuit is electrically connected to the main controller; the pre-charging circuit is used to pre-charge the battery pack; wherein the pre-charging current is not greater than a preset current threshold.

[0037] In one embodiment, the AGV BMS management system further includes:

[0038] A heating film is arranged around the battery pack;

[0039] A heating circuit is arranged on the power circuit board, and the heating circuit is electrically connected to the main controller and the heating film respectively; the heating circuit is used to provide the electric energy required for the heating film to generate heat.

[0040] In one embodiment, the AGV BMS management system further includes:

[0041] Multiple communication interface circuits are arranged on the drive control circuit board, and the multiple communication interface circuits are connected to the main controller; the multiple communication interface circuits are used for connecting the AGV central control system with the main controller, and for connecting external devices with the main controller.

[0042] In one embodiment, the AGV BMS management system includes a plurality of battery packs, and a plurality of battery protection boards electrically connected to the plurality of battery packs in a one-to-one correspondence; the plurality of battery protection boards each include a parallel communication interface circuit; the plurality of battery protection boards are communicatively connected via the parallel communication interface circuit;

[0043] The main controller of the battery protection board pre-stores the parallel operation mode. In the parallel operation mode, the main controller is used to execute the parallel ID diagnosis strategy and the parallel management strategy.

[0044] In one embodiment, the plurality of battery protection boards are preset with ID numbers of different sizes; under the parallel ID diagnosis strategy, the plurality of battery protection boards identify the battery protection board with the smallest ID number according to the ID numbers of the plurality of battery protection boards, and use the battery protection board with the smallest ID number as the host to execute the parallel management strategy;

[0045] Under the parallel management strategy, the host controls the operation of the main controllers of the multiple battery protection boards respectively based on the discharge control signal and the battery voltage signals, current detection signals and ambient temperature of the battery packs of the multiple battery protection boards, so as to control the discharge of the multiple battery packs to the AGV drive load;

[0046] The host also controls the operation of the main controllers of multiple battery protection boards respectively based on the charging control signal and the battery voltage signals, current detection signals and ambient temperature of the battery pack of multiple battery protection boards to control the charging of multiple battery packs.

[0047] The technical solution of the present invention adopts a BMS management system for AGV, including a charging power input terminal, an AGV drive load, a battery pack, an AGV starting circuit, an AGV central control system and a battery protection board. The drive control circuit board of the battery protection board is provided with a main control circuit, and the power circuit board of the battery protection board is provided with a switch array circuit. Among them, the AGV starting circuit is connected / disconnected from the power connection of the battery pack when triggered by the user. When the power connection of the battery pack is connected, the AGV central control system is powered on, and the AGV vehicle is in a starting state. At this time, the AGV central control system can identify the user's operation and output a corresponding discharge control signal according to the user's operation, which may specifically include a high-level discharge control signal for indicating that the AGV drive load is working, and a low-level discharge control signal for indicating that the AGV drive load stops working. When the main control circuit receives a high-level discharge control signal, the switch array circuit is controlled to conduct the circuit between the battery pack and the AGV drive load, the AGV drive load is powered on, and the AGV vehicle can move. When the main control circuit receives a low-level discharge control signal, the control switch array circuit disconnects the circuit between the battery pack and the AGV drive load. At this time, the AGV drive load loses power and the AGV vehicle stops moving. When the main control circuit detects that the voltage at the charging power input terminal does not exceed the preset voltage threshold, it means that there is no power input to the charging power input terminal, and the control switch array circuit is turned off and no charging is performed. When the main control circuit detects that the voltage at the charging power input terminal exceeds the preset voltage threshold, the control switch array circuit turns on the circuit between the battery pack and the charging power input terminal, and the battery pack is charged at this time. In this way, the present invention realizes the power supply separation between the AGV startup circuit and the AGV drive load, first connects the power supply of the AGV central control system through the AGV startup circuit, and then controls the power supply of the AGV drive load through the AGV central control system, thereby improving the power supply safety of the AGV. Moreover, the battery protection board of the present invention separates the drive control circuit board from the power circuit board, reducing the influence of electromagnetic interference of the switch array circuit and the like in the power circuit board on the main control circuit. If multiple battery packs need to be powered in parallel, it is only necessary to connect the main control circuits of multiple drive control circuit boards, and the signal is transmitted between the multiple drive control circuit boards without being affected by the power circuit boards. The system is more stable and has stronger scalability. Compared with the prior art, the present invention can solve the problem that the existing AGV BMS management system is easily affected by electromagnetic interference and lacks an effective expansion mechanism. BRIEF DESCRIPTION OF THE DRAWINGS

[0048] 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 described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0049] Figure 1 A schematic diagram of the structure of an embodiment of a BMS management system for AGV provided by the present invention;

[0050] Figure 2 A structural schematic diagram of another embodiment of the BMS management system for AGV provided by the present invention;

[0051] Figure 3 An electronic circuit diagram of a charging wake-up circuit of an embodiment of a BMS management system for AGV provided by the present invention;

[0052] Figure 4 This is an electronic circuit diagram of a temperature sampling circuit of an embodiment of a BMS management system for AGV provided by the present invention.

[0053] Description of Figure Numbers:

[0054]

[0055] The realization of the purpose, functional features and advantages of the present invention will be further explained in conjunction with embodiments and with reference to the accompanying drawings. DETAILED DESCRIPTION

[0056] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0057] It should be noted that all directional indications in the embodiments of the present invention (such as up, down, left, right, front, back, etc.) are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0058] In addition, the descriptions of "first", "second", etc. in the present invention are only used for descriptive purposes and cannot be understood as indicating or implying their relative importance or implicitly indicating the number of the indicated technical features. Therefore, the features defined as "first" and "second" may explicitly or implicitly include at least one of the features. In addition, the technical solutions between the various embodiments can be combined with each other, but they must be based on the ability of ordinary technicians in the field to implement them. When the combination of technical solutions is contradictory or cannot be implemented, it should be deemed that such a combination of technical solutions does not exist and is not within the scope of protection required by the present invention.

[0059] The BMS management system used by existing AGVs is mainly composed of a single circuit board, which integrates functional modules such as battery status monitoring, balancing management, and safety protection. However, the centralized signal processing of a single circuit board easily leads to increased electromagnetic interference, affecting the stability of the system. Moreover, the design of a single circuit board limits the scalability of the system and is not conducive to the parallel power supply of multiple battery packs.

[0060] The present invention provides a BMS management system for AGV.

[0061] See also Figure 1 In one embodiment of the present invention, the AGV BMS management system includes:

[0062] Charging power input terminal;

[0063] AGV drive load 200;

[0064] Battery pack 300;

[0065] The AGV startup circuit 400 is electrically connected to the first power supply terminal of the battery pack 300 ; the AGV startup circuit 400 is used to connect / disconnect the power supply connection of the battery pack 300 when triggered by the user.

[0066] It should be noted that the AGV startup circuit 400 may include a switching circuit and a low-voltage circuit. The switching circuit may include switching devices such as relays or switching tubes. When the switching circuit is triggered by the user, it can conduct the connection between the first power supply terminal of the battery pack 300 and the low-voltage circuit. At this time, the battery pack 300 can supply power to the AGV central control system 500 and other low-voltage loads through the low-voltage circuit. At this time, the AGV vehicle is in a startup state and can start to perform tasks. When the switching circuit is triggered by the user, it can also disconnect the connection between the first power supply terminal of the battery pack 300 and the low-voltage circuit. At this time, the AGV central control system 500 loses power and stops working. Among them, the low-voltage circuit may include a voltage conversion circuit, a voltage stabilization circuit, and a filter circuit.

[0067] The AGV central control system 500 is electrically connected to the AGV starting circuit 400 ; the AGV central control system 500 is used to output a corresponding discharge control signal when triggered by a user.

[0068] It should be noted that when the AGV central control system 500 is triggered by the user, it can output a high-level discharge control signal to instruct the battery pack 300 to supply power to the AGV drive load 200; it can also output a low-level discharge control signal to instruct the battery pack 300 to stop supplying power to the AGV drive load 200.

[0069] It should be noted that the AGV central control system 500 can also be connected to the AGV driving load 200 for communication, so as to control the operation of the AGV driving load 200 .

[0070] The battery protection board 100 includes a driving control circuit board and a power circuit board, and a first interface of the driving control circuit board is electrically connected to a second interface of the power circuit board.

[0071] It should be noted that the present embodiment divides the battery protection board 100 into two circuit boards. Among them, the drive control circuit board can provide control drive; the power circuit board can provide a controlled interface, which is directly electrically connected to the battery pack 300. The drive control circuit board processes lower signal levels, and the power circuit board processes higher currents and voltages. In this way, separating the drive control circuit board from the power circuit board can reduce the impact of electromagnetic interference on the control signal, thereby improving the reliability and stability of the battery protection board 100. Through physical isolation, the drive control circuit board can be prevented from being impacted by high voltage or high current in the power circuit board, reducing the risk of failure. Moreover, by separating the drive control circuit board from the power circuit board, when multiple battery packs 300 are powered in parallel, it is only necessary to connect multiple drive control circuit boards for communication, which simplifies the circuit, and the signal is transmitted between multiple drive control circuit boards, which is not affected by the power circuit board, and the system is more stable.

[0072] The switch array circuit 120 is arranged on the drive control circuit board; the switch array circuit 120 is electrically connected to the charging power input terminal, the power terminal of the AGV driving load 200, and the second power terminal of the battery pack 300 respectively; the switch array circuit 120 is used to control the conduction / disconnection of the circuit between the battery pack 300 and the charging power input terminal, and is used to control the conduction / disconnection of the circuit between the battery pack 300 and the AGV driving load 200.

[0073] It should be noted that the switch array circuit 120 controls the on / off switching of the circuit between the battery pack 300 and the charging power input terminal, and is used to control the charging of the battery pack 300 ; the switch array circuit 120 is used to control the on / off switching of the circuit between the battery pack 300 and the AGV drive load 200 , and is used to control the discharge of the battery pack 300 to the AGV drive load 200 .

[0074] It should be noted that the switch array circuit 120 may include a plurality of charging MOS tubes for controlling the on / off of the circuit between the battery pack 300 and the charging power input terminal, and a plurality of discharging MOS tubes for controlling the on / off of the circuit between the battery pack 300 and the AGV driving load 200. A plurality of charging MOS tubes and a plurality of discharging MOS tubes form a corresponding switch array, and the specific number and configuration of the MOS tubes can be set according to the specific requirements and system of the battery pack 300. For example, the switch array circuit 120 may include N pairs of parallel MOS tubes, each pair of MOS tubes includes a charging MOS tube and a discharging MOS tube, and the two ends of the charging MOS tube are respectively connected to the battery pack 300 and the charging power input terminal, and the two ends of the discharging MOS tube are respectively connected to the battery pack 300 and the AGV power load. Among them, N can be 18. In this way, by connecting multiple pairs of MOS tubes in parallel, a large current can be dispersed to multiple MOS tubes, thereby reducing the current burden on each MOS tube, and can also reduce the heat generation of a single MOS tube, thereby improving the reliability and life of the system. The switch array circuit 120 can also protect the circuit, for example, by connecting the TVS tube in parallel near the port of the AGV drive load 200 and / or the charging power input end. When the voltage exceeds its threshold, the TVS tube will quickly turn on and transfer the excess voltage energy to the ground, thereby protecting the working safety of the MOS tube.

[0075] It should be noted that the multiple discharge MOS tubes of the switch array circuit 120 can be partially turned on and partially turned off, which can be determined according to the required power of the AGV driving load 200; the multiple charging MOS tubes of the switch array circuit 120 can also be partially turned on and partially turned off, which can be determined according to the charging power of the battery pack 300, and there is no limitation here.

[0076] The main control circuit 110 is arranged on the power circuit board; the main control circuit 110 is electrically connected to the third power supply terminal of the battery pack 300, the controlled terminal of the switch array circuit 120, the control terminal of the AGV central control system 500, and the detection terminal of the charging power input terminal;

[0077] The main control circuit 110 is used to output a corresponding first drive control signal to drive the operation of the switch array circuit 120 according to the discharge control signal, so as to control the discharge of the battery pack 300 to the AGV drive load 200; and is used to output a corresponding second drive control signal to drive the operation of the switch array circuit 120 according to the voltage value of the charging power input terminal, so as to control the charging of the battery pack 300.

[0078] It should be noted that the driving load of the AGV has a large power and consumes a lot of electrical energy. In this embodiment, the power supply is first connected to the AGV starting circuit 400 to power the AGV central control system 500, and then the AGV central control system 500 controls whether the battery pack 300 supplies power to the driving load of the AGV.

[0079] It should be noted that when the user connects the charging power input terminal to a power source, for example, when the charging adapter interface of the AGV vehicle is connected to the power grid, the voltage at the charging power input terminal exceeds the preset voltage threshold, and the charging MOS tube of the control switch array circuit 120 is turned on to charge the battery pack 300; if the voltage at the charging power input terminal does not exceed the preset voltage threshold, the charging MOS tube of the control switch array circuit 120 is turned off, and the battery pack 300 is not charged at this time.

[0080] In this embodiment, the AGV startup circuit 400 is connected / disconnected from the power connection of the battery pack 300 when triggered by the user. When the power connection of the battery pack 300 is connected, the AGV central control system 500 is powered on, and the AGV vehicle is in the startup state. At this time, the AGV central control system 500 can identify the user's operation and output the corresponding discharge control signal according to the user's operation, which can specifically include a high-level discharge control signal for indicating that the AGV drive load 200 is working, and a low-level discharge control signal for indicating that the AGV drive load 200 stops working. When the main control circuit 110 receives a high-level discharge control signal, the multiple discharge MOS tubes of the control switch array circuit 120 are turned on. At this time, the circuit between the battery pack 300 and the AGV drive load 200 is turned on, the AGV drive load 200 is powered on, and the AGV vehicle can move. When the main control circuit 110 receives a low-level discharge control signal, the multiple discharge MOS tubes of the control switch array circuit 120 are turned off. At this time, the AGV drive load 200 loses power and the AGV vehicle stops moving. When the main control circuit 110 detects that the voltage at the charging power input terminal does not exceed the preset voltage threshold, it means that there is no power input at the charging power input terminal, and the multiple charging MOS tubes of the control switch array circuit 120 are turned off and no charging is performed. When the main control circuit 110 detects that the voltage at the charging power input terminal exceeds the preset voltage threshold, the multiple charging MOS tubes of the control switch array circuit 120 are turned on, and the circuit between the battery pack 300 and the charging power input terminal is turned on, and the battery pack 300 is charged at this time. In this way, this embodiment realizes the power supply separation between the AGV startup circuit 400 and the driving load of the AGV, firstly connects the power supply of the AGV central control system 500 through the AGV startup circuit 400, and then controls the power supply of the AGV driving load 200 through the AGV central control system 500, thereby improving the power supply safety of the AGV. Moreover, the battery protection board 100 of this embodiment separates the driving control circuit board from the power circuit board, reducing the influence of electromagnetic interference of the switch array circuit 120 and the like in the power circuit board on the main control circuit 110. If multiple battery packs 300 need to be powered in parallel, it is only necessary to connect the main control circuits 110 of multiple drive control circuit boards, and the signal is transmitted between the multiple drive control circuit boards without being affected by the power circuit boards. The system is more stable and has stronger scalability. Compared with the prior art, this embodiment can solve the problem that the BMS management system of the existing AGV is easily affected by electromagnetic interference and lacks an effective expansion mechanism.

[0081] In the present invention, when the AGV startup circuit 400 is triggered by the user, the power connection of the battery pack 300 is connected / disconnected. When the power connection of the battery pack 300 is connected, the AGV central control system 500 is powered on, and the AGV vehicle is in the startup state. At this time, the AGV central control system 500 can identify the user's operation and output the corresponding discharge control signal according to the user's operation, which can specifically include a high-level discharge control signal for indicating that the AGV drive load 200 is working, and a low-level discharge control signal for indicating that the AGV drive load 200 stops working. When the main control circuit 110 receives a high-level discharge control signal, the multiple discharge MOS tubes of the control switch array circuit 120 are turned on. At this time, the circuit between the battery pack 300 and the AGV drive load 200 is turned on, the AGV drive load 200 is powered on, and the AGV vehicle can move. When the main control circuit 110 receives a low-level discharge control signal, the multiple discharge MOS tubes of the control switch array circuit 120 are turned off. At this time, the AGV drive load 200 loses power and the AGV vehicle stops moving. When the main control circuit 110 detects that the voltage at the charging power input terminal does not exceed the preset voltage threshold, it means that there is no power input at the charging power input terminal, and the multiple charging MOS tubes of the control switch array circuit 120 are turned off and no charging is performed. When the main control circuit 110 detects that the voltage at the charging power input terminal exceeds the preset voltage threshold, the multiple charging MOS tubes of the control switch array circuit 120 are turned on, and the circuit between the battery pack 300 and the charging power input terminal is turned on, and the battery pack 300 is charged at this time. In this way, the present invention realizes the power supply separation of the AGV starting circuit 400 and the driving load of the AGV, firstly connects the power supply of the AGV central control system 500 through the AGV starting circuit 400, and then controls the power supply of the AGV driving load 200 through the AGV central control system 500, thereby improving the power supply safety of the AGV. Moreover, the battery protection board 100 of the present invention separates the driving control circuit board from the power circuit board, reducing the influence of electromagnetic interference of the switch array circuit 120 and the like in the power circuit board on the main control circuit 110. If multiple battery packs 300 need to be powered in parallel, it is only necessary to connect the main control circuits 110 of multiple drive control circuit boards, and the signal is transmitted between the multiple drive control circuit boards without being affected by the power circuit boards. The system is more stable and has stronger scalability. Compared with the prior art, the present invention can solve the problem that the existing AGV BMS management system is easily affected by electromagnetic interference and lacks an effective expansion mechanism.

[0082] See also Figure 2 In one embodiment of the present invention, the main control circuit 110 includes:

[0083] The analog front-end circuit 112 is disposed on the driving control circuit board; the analog front-end circuit 112 is electrically connected to the battery pack 300, the switch array circuit 120, and the charging power input terminal respectively;

[0084] The analog front end circuit 112 includes:

[0085] A charge and discharge drive control module, used for outputting a first drive control signal / a second drive control signal to drive the switch array circuit 120 to work;

[0086] A voltage acquisition module, used to acquire the battery voltage of the battery pack 300 and output a corresponding battery voltage signal to the control circuit;

[0087] A charging detection module is used to collect the voltage at the input end of the charging power supply and output a corresponding charging control signal;

[0088] The main control circuit 110 further includes:

[0089] The main controller 111 is arranged on the driving control circuit board; the main controller 111 is electrically connected to the third power supply terminal of the battery pack 300, the interactive terminal of the analog front-end circuit 112, and the control terminal of the AGV central control system 500;

[0090] The main controller 111 is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the operation of the switch array circuit 120 according to the discharge control signal and the battery voltage signal; and is used to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the operation of the switch array circuit 120 according to the charge control signal and the battery voltage signal.

[0091] It should be noted that the analog front-end circuit 112 may include an AFE chip of model MT9818. The AFE chip has a built-in analog-to-digital converter and supports the monitoring of the voltage of multiple series-connected batteries. The AFE chip also supports protection functions such as discharge overcurrent protection, discharge short circuit protection, overvoltage protection, undervoltage protection, and voltage stabilization. The charge and discharge drive control module of the AFE chip integrates a discharge low-side driver and a charge low-side driver, and can output a corresponding first drive control signal / second drive control signal to drive the operation of the switch array circuit 120 according to the control of the main controller.

[0092] Please note that Figure 3, the charging detection module may include a charging wake-up circuit, which may include a first resistor R1, a second resistor R2, a third resistor R3, a fourth resistor R4, a fifth resistor R5, a sixth resistor R6, a first transistor Q1, a second transistor Q2, a first capacitor C1, a voltage stabilizing diode DW, a first diode D1 and a second diode D2, the VP terminal is connected to the charging power input terminal, and the P- terminal is connected to the power input terminal of the charging low-side driver of the charging and discharging drive control module. When the voltage at the charging power input terminal exceeds the preset voltage threshold, the CHG_WAKE terminal inputs a high level, the second transistor Q2 is turned on, the VP terminal and the P- terminal are turned on, and a high-level charging control signal is output. At this time, the main controller 111 can control the charging low-side driver of the charging and discharging drive control module to output a first drive control signal, and correspondingly drive the multiple charging MOS tubes of the switch array circuit 120 to turn on, and control the battery pack 300 to charge. When the voltage at the charging power input terminal does not exceed the preset voltage threshold, the battery pack 300 is controlled to stop charging.

[0093] It should be noted that the main controller 111 can analyze the battery voltage signal to confirm whether the battery voltage of the battery pack 300 is within the preset safety range. If it is within the preset safety range and the discharge control signal is at a high level, the charge and discharge drive control module is controlled to output a corresponding first drive control signal to drive the switch array circuit 120 to conduct the circuit connection between the battery pack 300 and the AGV drive load 200, otherwise the control drive switch array circuit 120 is disconnected from the circuit connection between the battery pack 300 and the AGV drive load 200, and discharging is prohibited at this time. If it is within the preset safety range and the charging control signal is at a high level, the charge and discharge drive control module is controlled to output a corresponding second drive control signal to drive the switch array circuit 120 to conduct the circuit connection between the battery pack 300 and the charging power input terminal, otherwise the control drive switch array circuit 120 is disconnected from the circuit connection between the battery pack 300 and the charging power input terminal, and charging is prohibited at this time.

[0094] See also Figure 2 In one embodiment of the present invention, the AGV BMS management system further includes:

[0095] The current sampling resistor 130 is disposed on the power circuit board, one end of the current sampling resistor 130 is electrically connected to the battery pack 300, the other end of the current sampling resistor 130 is electrically connected to the switch array circuit 120, and the output end of the current sampling resistor 130 is electrically connected to the analog front-end circuit 112;

[0096] The analog front end circuit 112 further includes:

[0097] A current detection module, which is used to detect the current flowing through the current sampling resistor 130 and output a corresponding current detection signal;

[0098] The main controller 111 is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the switch array circuit 120 to disconnect the battery pack 300 from the AGV drive load 200 when it is determined according to the current detection signal that the discharge current of the battery pack 300 exceeds the preset current range; and to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the switch array circuit 120 to disconnect the battery pack 300 from the charging power input terminal when it is determined according to the current detection signal that the charging current of the battery pack 300 exceeds the preset current range.

[0099] In this embodiment, the AFE chip model MT9818 also has a built-in coulomb charge counter, supports current measurement, and can measure the current flowing through the current sampling resistor 130. In this way, when the charging current / discharging current of the battery pack 300 exceeds the preset current range, the switch array circuit 120 is driven to stop charging / discharging, protect the battery pack 300 from safe charging and discharging, and extend its service life.

[0100] See also Figure 2 In one embodiment of the present invention, the battery pack 300 includes a plurality of battery cells, and the voltage acquisition module is further used to acquire the battery voltages of the plurality of battery cells; the AGV BMS management system further includes:

[0101] The voltage balancing circuit 140 is disposed on the driving control circuit board. The voltage balancing circuit 140 is electrically connected to the analog front-end circuit 112 and multiple battery cells respectively. The voltage balancing circuit 140 is used to balance the battery voltages of multiple battery cells of the battery pack 300.

[0102] The analog front end circuit 112 further includes:

[0103] A voltage balancing control module, used for outputting a third driving control signal to drive the voltage balancing circuit 140 to work;

[0104] The main controller 111 is used to control the voltage balancing control module to output a corresponding third driving control signal to drive the voltage balancing circuit 140 to work when it is determined that the battery voltages of the plurality of battery cells are unbalanced according to the battery voltages of the plurality of battery cells.

[0105] It should be noted that the AFE chip model MT9818 also integrates a battery balancing field effect transistor, which can output a corresponding third drive control signal to drive the voltage balancing circuit 140. Among them, the voltage acquisition module of the AFE chip can respectively collect the voltages of multiple battery cells of the battery pack 300, and can be filtered through magnetic beads to enhance the circuit's anti-static discharge capability. The main controller 111 can calculate the average voltage of the battery pack 300 based on the voltages of multiple battery cells to determine the voltage state of each battery cell, and determine whether certain battery cells need to be charged or discharged based on the comparison result of the voltage of the battery cell with the average voltage. If the voltage of a battery cell is lower than the average voltage, it needs to be charged. If the voltage of a battery cell is higher than the average voltage, it needs to be discharged.

[0106] It should be noted that the voltage equalization circuit 140 can set multiple PNP drive transistors in the charging circuit and the discharge circuit of the battery pack respectively to control the charging and discharging operations of different battery cells. A voltage regulator diode can also be connected in series in the charging circuit to provide overvoltage protection in the equalization circuit to avoid damage to the circuit due to battery overvoltage. A discharge resistor can be connected in series in the discharge circuit to limit the current during the discharge process to avoid damage caused by excessive discharge. During charging, the main controller 111 controls the inflow of charging current through the PNP drive transistor to ensure that the voltage of the low-voltage battery cell gradually rises. At this time, the voltage regulator provides protection to avoid damage to the battery due to overvoltage charging. During discharge, the main controller 111 controls the outflow of discharge current through the PNP drive transistor to reduce the voltage of the high-voltage unit. The discharge resistor is used to limit the current during the discharge process to avoid damage caused by excessive discharge.

[0107] See also Figure 2 In one embodiment of the present invention, the main controller 111 includes a temperature acquisition port, which is arranged close to the battery pack 300; the main controller 111 is also used to collect the ambient temperature of the battery pack 300 and work according to the ambient temperature of the battery pack 300.

[0108] Please note that Figure 4, the ambient temperature collected by the temperature collection port can be transmitted to the main controller 111 through the temperature sampling circuit. The temperature sampling circuit includes an inductor L, a seventh resistor R7, an eighth resistor R8 and a second capacitor C2, wherein the NTC terminal is electrically connected to the temperature collection port and is a temperature signal input terminal; the TEN terminal is electrically connected to the main controller 111 and is an enable control terminal; the AD_NTC terminal is electrically connected to the main controller 111 and is a temperature signal output terminal. The sampled temperature signal can be output to the main controller 111, and the obtained temperature signal is more accurate. It can be understood that in order to improve the accuracy of battery ambient temperature detection, temperature collection ports can be set at different positions of the battery pack 300, such as near the first battery cell, near the middle battery cell and near the last battery cell of the battery pack 300, respectively, to detect the ambient temperature of different positions of the battery pack, and calculate the average temperature. In this way, the accuracy of detecting the ambient temperature of the battery pack can be improved.

[0109] It should be noted that if the ambient temperature is within a safe range, the main controller 111 allows the switch array circuit 120 and the voltage balancing circuit 140 to operate normally. If the ambient temperature is greater than the first preset temperature threshold, the main controller 111 may limit the operation of the switch array circuit 120, such as limiting the number of conduction of multiple charging MOS tubes or multiple discharging MOS tubes of the switch array circuit 120. If the ambient temperature is greater than the second preset temperature threshold, the main controller 111 may limit the operation of the voltage balancing circuit 140, such as reducing the charging current or discharging current of the battery balancing process.

[0110] In a feasible implementation manner, the AGV BMS management system further includes:

[0111] A heating film 170 is disposed around the battery pack 300;

[0112] The heating circuit 160 is disposed on the power circuit board, and is electrically connected to the main controller 111 and the heating film 170 respectively; the heating circuit 160 is used to provide the electric energy required for the heating film 170 to generate heat.

[0113] It should be noted that if the ambient temperature is lower than the minimum preset temperature threshold, the main controller 111 can control the heating circuit 160 to operate so as to increase the ambient temperature of the battery pack 300 to prevent the performance of the battery cells from being degraded or damaged.

[0114] See also Figure 2 In one embodiment of the present invention, the AGV BMS management system further includes:

[0115] The pre-charging circuit 150 is arranged on the power circuit board, and the input end of the pre-charging circuit 150 is electrically connected to the input end of the charging power supply; the output end of the pre-charging circuit 150 is electrically connected to the other end of the current sampling circuit; the controlled end of the pre-charging circuit 150 is electrically connected to the main controller 111; the pre-charging circuit 150 is used to pre-charge the battery pack 300; wherein the pre-charging charging current is not greater than the preset current threshold.

[0116] In this embodiment, when the battery pack 300 needs to be charged, the main controller 111 first starts the pre-charging circuit 150. The pre-charging circuit 150 can limit the charging current to not exceed the preset current threshold according to the preset current threshold, so as to slowly increase the voltage level of the battery and ensure that the battery is charged under stable conditions. After the voltage of the battery pack 300 reaches the safety threshold, the main controller 111 controls the charge and discharge drive control module to drive the switch array circuit 120 to charge in a normal charging mode.

[0117] See also Figure 2 In one embodiment of the present invention, the AGV BMS management system further includes:

[0118] Multiple communication interface circuits 180 are arranged on the drive control circuit board, and the multiple communication interface circuits are connected to the main controller 111; the multiple communication interface circuits are used for connecting the AGV central control system 500 with the main controller 111, and for connecting external devices with the main controller 111.

[0119] In this embodiment, the multiple communication interface circuits 180 may specifically include two isolated CAN communication interfaces, one for parallel communication, and one for conventional host computer monitoring, program upgrades, and load device communications. Also, an isolated 485 communication interface is included for communication with an external screen or other device. Also, a TTL SPI communication interface is included, which is reserved for communication with a small screen. Also, a TTL UART communication interface is included, which is reserved for Bluetooth and Wifi module communications. In this way, this embodiment can be configured with different communication interfaces (such as CAN, 485, TTL SPI, TTL UART), which can meet the communication requirements of different external devices, and has strong flexibility, so that the system can achieve an extended connection with the main controller 111 according to the control requirements of the AGV, which facilitates the parallel communication of the battery protection board 100.

[0120] See also Figure 2 In one embodiment of the present invention, the BMS management system for AGV includes a plurality of battery packs 300, and a plurality of battery protection boards 100 electrically connected to the plurality of battery packs 300 in a one-to-one correspondence; the plurality of battery protection boards 100 each include a parallel communication interface circuit; the plurality of battery protection boards 100 are communicatively connected to each other through the parallel communication interface circuit;

[0121] The main controller 111 of the battery protection board 100 pre-stores a parallel operation mode. In the parallel operation mode, the main controller 111 is used to execute a parallel ID diagnosis strategy and a parallel management strategy.

[0122] In one feasible implementation, multiple battery protection boards 100 are preset with IDs of different sizes; under the parallel ID diagnosis strategy, multiple battery protection boards 100 identify the battery protection board 100 with the smallest ID according to the IDs of the multiple battery protection boards 100, and use the battery protection board 100 with the smallest ID as the host to execute the parallel management strategy;

[0123] Under the parallel management strategy, the host controls the operation of the main controller 111 of the multiple battery protection boards 100 based on the discharge control signal and the battery voltage signals, current detection signals, and ambient temperature of the corresponding battery pack 300 of the multiple battery protection boards 100, so as to control the discharge of the multiple battery packs 300 to the AGV drive load 200;

[0124] The host also controls the operation of the main controller 111 of the multiple battery protection boards 100 based on the charging control signal and the battery voltage signals, current detection signals of the multiple battery protection boards 100 and the ambient temperature of the corresponding battery packs 300 to control the charging of the multiple battery packs 300.

[0125] In this embodiment, the parallel ID diagnostic strategy can ensure that there is a central control unit in the system, which is responsible for coordinating the operations of other battery protection boards 100 to avoid conflicts caused by multi-host control. After the host is determined, under the parallel management strategy, the host controls the main controller 111 of each battery protection board 100 according to the received charging control signal, combined with the battery voltage signal, current detection signal of each battery protection board 100 and the ambient temperature of the battery pack 300, so as to effectively manage the charging process of the battery pack 300, specifically including: voltage monitoring to ensure that the voltage of each battery pack 300 is within a safe range; current control to adjust the charging current of each battery pack 300 according to the state of the battery pack 300 to avoid overcharging; temperature monitoring to prevent the battery pack 300 from being damaged due to overheating. Similarly, after receiving the discharge control signal, the host will control the discharge operation of multiple battery protection boards 100 according to the battery voltage signal, current detection signal and the ambient temperature of the battery pack 300, including: voltage balance, during the discharge process, to avoid over-discharge of a single battery in the battery pack 300 to extend the battery life; safe discharge, monitoring the discharge current to ensure the safety and reliability of the discharge process; temperature monitoring, to prevent safety hazards caused by battery heating during the discharge process. In this way, this embodiment controls the main controller 111 corresponding to each battery pack 300 through the host, and then controls the charging / discharging of the battery cells of the corresponding battery pack 300 through the main controller 111, thereby achieving comprehensive monitoring and efficient management of multiple battery packs 300.

[0126] It should be noted that the specific steps of the parallel management strategy include:

[0127] Step S10 , based on the states of the multiple battery packs 300 , determining whether the multiple battery packs 300 meet the parallel connection condition.

[0128] Among them, the battery voltage signals, current detection signals and ambient temperature of multiple battery packs 300 can be obtained, and it is determined whether the battery voltage signals, current detection signals and ambient temperature of multiple battery packs 300 are within the preset fluctuation range of parallel operation. If so, the parallel operation condition is met, otherwise, the parallel operation condition is not met.

[0129] Step S20 , if the parallel condition is met, then multiple battery protection boards 100 and their corresponding battery packs 300 are sequentially connected to the host and its corresponding battery packs 300 from small to large according to the voltages of the multiple battery packs 300 .

[0130] In step S30 , after the battery packs are connected in parallel, the host controls the operation of the main controller 111 of the corresponding battery protection board 100 to control the charging / discharging of all the battery packs 300 .

[0131] It should be noted that the AGV driving load 200 may include multiple ones, and before step S30, the specific steps of the parallel management strategy also include:

[0132] In step A10 , the SOC state, SOH state and SOP state of the plurality of battery packs 300 are calculated according to the states of the plurality of battery packs 300 .

[0133] It should be noted that SOC (State of Charge) indicates the current state of charge of the battery pack, that is, the percentage of remaining power in the battery pack. The SOC status can estimate the remaining power of the battery pack and help determine the battery life. SOH (State of Health) reflects the overall health status or life status of the battery pack. The SOH status can evaluate the performance degradation and aging of the battery pack. SOP (State of Power) describes the current power state of the battery pack and indicates the power capacity that the battery pack can provide or absorb. The SOP status can monitor how much power the battery pack can provide in actual use and ensure that the battery pack operates within a safe range.

[0134] It should be noted that the calculation of the SOC state can be calculated in a combination of the ampere-hour integration method, the battery internal resistance OCV correction method, and the low-temperature capacity compensation algorithm. Among them, the ampere-hour integration method estimates the charge state of the battery pack by accumulating the charge and discharge current of the battery pack. In the battery internal resistance OCV correction method, the internal resistance (Ohmic Resistance) will affect the open circuit voltage (OCV) of the battery. The correction algorithm can adjust the SOC calculation according to the change of the battery internal resistance to improve accuracy. In the low-temperature capacity compensation algorithm, the performance of the battery pack will decrease and the capacity will decrease at low temperatures. The algorithm adjusts the SOC under low temperature conditions to reflect the actual performance of the battery pack. In this embodiment, since the internal resistance of the battery pack 300 is basically fixed in a small range, the internal resistance parameter can be written as a fixed value, and the OCV value is calculated as a correction condition based on the real-time current and internal resistance during actual operation. The calculation of the SOC state is mainly based on the ampere-hour integration method, and OCV is used as a correction parameter. Among them, the basic principle of the ampere-hour integration method is as follows:

[0135]

[0136] Among them, SOC0 is the battery capacity at the initial moment, C is the total capacity of the battery, Represents the integral of the battery current I over time [0, t]. The low temperature capacity compensation algorithm determines the actual available capacity in the low temperature range through battery data and performs a comprehensive calculation based on the reverse effect of temperature rise on capacity during charging and discharging, and finally calculates a total capacity that conforms to the actual measurement results. In this way, the SOC states of multiple battery packs 300 can be comprehensively calculated, and the calculation results are relatively accurate.

[0137] It should be noted that the calculation of the SOH state can be done by the cycle counting method, which is to calculate the cycle number based on the cumulative charging capacity and compare it with the nominal cycle life of the battery. This calculation method is not easy to expose the problems of the battery itself, and avoids the deviation of the user's understanding causing deviation in the SOH state calculation.

[0138] It should be noted that the SOP state can be calculated based on the parallel SOP power, the battery SOP power and the current balance SOP power; step A10, according to the states of the multiple battery packs 300, the steps of calculating the SOP states of the multiple battery packs 300 include A11 to A14:

[0139] Step A11 , calculating the parallel SOP power according to the power required by the AGV to drive the load 200 .

[0140] For example, suppose the power required by AGV to drive load 200 is P load , calculate the parallel SOP power P SOP1 (i.e. total power demand), can be expressed as:

[0141] Formula 1: P SOP1 =P load × Safety factor;

[0142] The safety factor is a factor greater than 1, which is used to ensure that the system can still work normally under peak load. load And the safety factor can be sent by the AGV central control system 500 to the host computer to facilitate calculation.

[0143] Step A12, calculating the battery SOP power P according to the battery rated parameters of the plurality of battery packs 300 SOP2 .

[0144] For example, the rated voltage V of the battery pack 300 may be obtained. rated With rated discharge current I rated , calculate the battery SOP power, which can be expressed as:

[0145] Formula 2: P SOP2 =V rated ×I rated ;

[0146] If the efficiency of the battery pack 300 needs to be considered, Formula 2 can be adjusted to:

[0147] Formula 3: P SOP2 =V rated ×I rated ×Efficiency.

[0148] Step A3 , calculating the current balancing SOP power according to the states of the plurality of battery packs 300 .

[0149] The current balancing power is calculated to ensure that the current between the battery packs 300 is evenly distributed. The formula is:

[0150] Formula 4:

[0151] Wherein, N is the number of battery packs 300, i is the i-th battery pack 300, and I i is the current value of the i-th battery pack 300, which can be calculated based on the current detection signal, V i is the voltage value of the i-th battery pack 300, which can be calculated according to the battery voltage signal.

[0152] Step A14, determining the minimum value of the parallel SOP power, the battery SOP power and the current balance SOP power, and taking the minimum value as the SOP state of the corresponding battery group.

[0153] In this way, this embodiment can obtain relatively accurate parallel SOP power, battery SOP power and current balance SOP power.

[0154] Step S30 includes step S31:

[0155] Step S31, in response to the discharge control signal, based on the SOC status, SOH status and SOP status of multiple battery packs 300, the host is used to assign a corresponding AGV drive load 200 to the corresponding battery pack 300, and control the operation of the main controller 111 of multiple battery protection boards 100, so that the discharge of the corresponding battery pack 300 is adapted to the required power of the multiple AGV drive loads 200; wherein, the SOC status of the battery pack 300 is used to indicate the power status of the battery pack 300; the SOH status is used to indicate the number of cycles of the battery pack 300; and the SOP status is used to indicate the maximum output power of the battery pack 300.

[0156] It should be noted that the weight can be set according to the SOC state, SOH state and SOP state of each battery pack 300, so that the discharge of the corresponding battery pack 300 is adapted to the required power of multiple AGV drive loads 200. Among them, the host continuously monitors the SOC state, SOH state and SOP state of multiple battery packs 300, and dynamically adjusts the load distribution strategy according to real-time data. In this way, this embodiment can reasonably distribute the load according to the SOC state, SOH state and SOP state of each battery pack 300, ensure the balanced operation of the battery pack 300, and avoid excessive discharge or overload of a battery pack 300.

[0157] It should be noted that the parallel operation mode may also include a pre-execution strategy. Under the pre-execution strategy, in response to the discharge control signal, the multiple discharge MOS tubes of the switch array circuit 120 of all battery protection boards 100 are controlled to be turned on to provide power at the fastest speed, and the current value of the current sampling resistor 130 is detected at the same time, and the multiple discharge MOS tubes of the switch array circuit 120 of multiple battery protection boards 100 are turned off in sequence until the power supply of the battery pack 300 corresponding to the remaining conductive discharge MOS tubes is slightly greater than the required power of the AGV drive load 200.

[0158] It should be noted that the parallel operation mode may also include a pre-charging strategy. Under the pre-charging strategy, in response to the charging control signal, the pre-charging circuit 150 of each battery protection board 100 is controlled to start, until the battery voltage of the corresponding battery pack 300 reaches the safety threshold, and then the driving switch array circuit 120 is controlled to work and charge in a normal charging mode.

[0159] It should be noted that the BMS management system for AGV may also include an alarm component, which is connected to the main controller 111 and is used to issue an alarm prompt message when the battery voltage, charge and discharge current, and ambient temperature of the battery pack 300 are abnormal.

[0160] It should be noted that the main controller 111 also pre-stores a single-board operation mode, which is used to start the working process of a single battery protection board. In the single-board operation mode, the main controller 111 is used to control the operation of the analog front-end circuit 112, the heating circuit 160, the pre-charging circuit 150 and the alarm component according to the charging control signal, the battery voltage signal, the current detection signal and the ambient temperature of the battery pack 300, and to control the operation of the analog front-end circuit 112, the heating circuit 160 and the alarm component according to the discharge control signal, the battery voltage signal, the current detection signal and the ambient temperature of the battery pack 300. Among them, the operation steps of the single-board operation mode include:

[0161] Step S101, obtaining the battery voltage signal, the current detection signal and the ambient temperature of the battery pack 300, and determining whether the state of the battery pack 300 is abnormal; wherein,

[0162] If the battery voltage of the battery pack 300 is between the minimum voltage threshold and the maximum voltage threshold, and the current flowing through the current sampling resistor 130 is within the preset current range, and the ambient temperature of the battery pack 300 is between the minimum preset temperature threshold and the maximum preset temperature threshold, the state of the battery pack 300 is judged to be normal; otherwise, the state of the battery pack 300 is judged to be abnormal, and the alarm component is controlled to issue an alarm prompt message.

[0163] In step S102, if the ambient temperature of the battery pack 300 is lower than the minimum preset temperature threshold, the heating circuit 160 is controlled to operate to increase the temperature of the environment where the battery pack 300 is located, and heating is stopped when the ambient temperature of the battery pack 300 reaches the minimum preset temperature threshold.

[0164] Step S103, in response to the charging control signal, if the battery pack 300 is in a normal state, the pre-charging circuit 150 is started to pre-charge the battery pack 300 until the battery pack 300 reaches a safety threshold, and then the charge and discharge drive control module is controlled to drive multiple charging MOS tubes of the switch array circuit 120 to turn on to charge the battery pack 300.

[0165] Step S104 , in response to the discharge control signal, if the battery pack 300 is in a normal state, determining whether the battery pack 300 is in a balanced state based on the battery voltages of the battery cells of the battery pack 300 .

[0166] If so, the charge and discharge drive control module is controlled to drive the multiple discharge MOS tubes of the switch array circuit 120 to be turned on, so as to discharge the battery pack 300 and supply power to the AGV drive load 200 .

[0167] If not, the voltage balancing control module is controlled to drive the voltage balancing circuit 140 to achieve battery voltage balancing of multiple battery cells in the battery pack 300, and after the battery pack 300 is in a balanced state, the charge and discharge drive control module is controlled to drive multiple discharge MOS tubes of the switch array circuit 120 to turn on, so as to discharge the battery pack 300 and supply power to the AGV drive load 200.

[0168] In this way, the present embodiment can realize single-board operation or multi-board parallel operation, and the operation mode is more flexible and scalable. When multiple battery packs are powered in parallel, it is only necessary to connect the main controllers 111 of multiple drive control circuit boards for communication, which simplifies the circuit, and the signal is transmitted between multiple drive control circuit boards without being affected by the power circuit board, making the system more stable.

[0169] The above description is only an exemplary embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the technical concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A BMS management system for AGV, characterized in that: include: Charging power input terminal; AGV drives the load; Battery pack; An AGV start-up circuit, the AGV start-up circuit being electrically connected to the first power supply terminal of the battery pack; the AGV start-up circuit being used to connect / disconnect the power supply connection of the battery pack when triggered by a user; An AGV central control system, the AGV central control system being electrically connected to the AGV starting circuit; the AGV central control system being configured to output a corresponding discharge control signal when triggered by a user; The battery protection board comprises a drive control circuit board and a power circuit board, wherein a first interface of the drive control circuit board is electrically connected to a second interface of the power circuit board; A switch array circuit is arranged on the drive control circuit board; the switch array circuit is electrically connected to the charging power input terminal, the power terminal of the AGV driving load, and the second power terminal of the battery pack respectively; the switch array circuit is used to control the conduction / disconnection of the circuit between the battery pack and the charging power input terminal, and to control the conduction / disconnection of the circuit between the battery pack and the AGV driving load; A main control circuit is arranged on the power circuit board; the main control circuit is electrically connected to the third power supply terminal of the battery pack, the controlled end of the switch array circuit, the control end of the AGV central control system, and the detection end of the charging power input end respectively; The main control circuit is used to output a corresponding first drive control signal according to the discharge control signal to drive the operation of the switch array circuit to control the discharge of the battery pack to the AGV drive load; and is used to output a corresponding second drive control signal according to the voltage value of the charging power input terminal to drive the operation of the switch array circuit to control the charging of the battery pack.

2. The AGV BMS management system according to claim 1, characterized in that: The main control circuit comprises: An analog front-end circuit is arranged on the drive control circuit board; the analog front-end circuit is electrically connected to the battery pack, the switch array circuit, and the charging power input terminal respectively; Wherein, the analog front-end circuit comprises: A charge and discharge drive control module, used for outputting the first drive control signal / the second drive control signal to drive the switch array circuit to operate; A voltage acquisition module, used for acquiring the battery voltage of the battery pack and outputting a corresponding battery voltage signal to the control circuit; A charging detection module, used to collect the voltage at the input end of the charging power supply and output a corresponding charging control signal; The main control circuit also includes: A main controller is arranged on the drive control circuit board; the main controller is electrically connected to the third power supply terminal of the battery pack, the interactive terminal of the analog front-end circuit, and the control terminal of the AGV central control system respectively; The main controller is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the operation of the switch array circuit according to the discharge control signal and the battery voltage signal; and is used to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the operation of the switch array circuit according to the charge control signal and the battery voltage signal.

3. The AGV BMS management system according to claim 2, characterized in that: Also includes: A current sampling resistor is arranged on the power circuit board, one end of the current sampling resistor is electrically connected to the battery pack, the other end of the current sampling resistor is electrically connected to the switch array circuit, and the output end of the current sampling resistor is electrically connected to the analog front-end circuit; The analog front end circuit also includes: A current detection module, the current detection module is used to detect the current flowing through the current sampling resistor and output a corresponding current detection signal; The main controller is used to control the charge and discharge drive control module to output a corresponding first drive control signal to drive the switch array circuit to disconnect the battery pack from the AGV drive load when it is determined according to the current detection signal that the discharge current of the battery pack exceeds a preset current range; and to control the charge and discharge drive control module to output a corresponding second drive control signal to drive the switch array circuit to disconnect the battery pack from the charging power input terminal when it is determined according to the current detection signal that the charging current of the battery pack exceeds a preset current range.

4. The AGV BMS management system according to claim 3, characterized in that: The battery pack includes a plurality of battery cells, and the voltage acquisition module is also used to collect the battery voltages of the plurality of battery cells; the AGV BMS management system also includes: A voltage balancing circuit is arranged on the driving control circuit board, and the voltage balancing circuit is electrically connected to the analog front-end circuit and the plurality of battery cells respectively; the voltage balancing circuit is used to balance the battery voltages of the plurality of battery cells of the battery pack; The analog front end circuit also includes: A voltage balancing control module, used for outputting a third driving control signal to drive the voltage balancing circuit to work; The main controller is used to control the voltage balancing control module to output a corresponding third driving control signal to drive the voltage balancing circuit to work when it is determined that the battery voltages of the multiple battery cells are unbalanced according to the battery voltages of the multiple battery cells.

5. The AGV BMS management system according to claim 4, characterized in that: The main controller comprises a temperature acquisition port, and the temperature acquisition port is arranged close to the battery pack; the main controller is also used to collect the ambient temperature of the battery pack and operate according to the ambient temperature of the battery pack.

6. The AGV BMS management system according to claim 5, characterized in that: Also includes: A pre-charging circuit is provided on the power circuit board, and an input end of the pre-charging circuit is electrically connected to the charging power input end; The output end of the pre-charging circuit is electrically connected to the other end of the current sampling circuit; the controlled end of the pre-charging circuit is electrically connected to the main controller; the pre-charging circuit is used to pre-charge the battery pack; wherein the pre-charging current is not greater than a preset current threshold.

7. The AGV BMS management system according to claim 6, characterized in that: Also includes: A heating film is arranged around the battery pack; A heating circuit is arranged on the power circuit board, and the heating circuit is electrically connected to the main controller and the heating film respectively; the heating circuit is used to provide the electric energy required for the heating film to generate heat.

8. The AGV BMS management system according to claim 7, characterized in that: Also includes: A plurality of communication interface circuits are arranged on the drive control circuit board, and the plurality of communication interface circuits are connected to the main controller; The plurality of communication interface circuits are used for connecting the AGV central control system with the main controller, and for connecting external devices with the main controller.

9. The AGV BMS management system according to claim 8, characterized in that: The AGV BMS management system includes a plurality of battery packs, and a plurality of battery protection boards electrically connected to the plurality of battery packs in a one-to-one correspondence; the plurality of battery protection boards each include a parallel communication interface circuit; the plurality of battery protection boards are communicatively connected via the parallel communication interface circuit; The main controller of the battery protection board pre-stores the parallel operation mode. In the parallel operation mode, the main controller is used to execute the parallel ID diagnosis strategy and the parallel management strategy.

10. The AGV BMS management system according to claim 9, characterized in that: The plurality of battery protection boards are preset with number IDs of different sizes; under the parallel ID diagnosis strategy, the plurality of battery protection boards identify the battery protection board with the smallest number ID according to the number IDs of the plurality of battery protection boards, and use the battery protection board with the smallest number ID as the host to execute the parallel management strategy; Under the parallel management strategy, the host controls the operation of the main controllers of the multiple battery protection boards respectively based on the discharge control signal and the battery voltage signals, current detection signals and ambient temperature of the battery packs of the multiple battery protection boards, so as to control the discharge of the multiple battery packs to the AGV drive load; The host also controls the operation of the main controllers of multiple battery protection boards respectively based on the charging control signal and the battery voltage signals, current detection signals and ambient temperature of the battery pack of multiple battery protection boards to control the charging of multiple battery packs.

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