Distributed active equalization system

Abstract

The invention provides a distributed active equalization system. The distributed active equalization system comprises a switch array module, a bidirectional DCDC converter module, a control module and a voltage feedback module. The input end of the switch array module is connected with the positive electrodes of the multiple strings of battery cells, and the output end of the switch array module is connected with the VO positive electrode end charge and the negative electrode end chargeN of the bidirectional DCDC converter module. The control module controls the optocoupler in the switch array through an IO pin, and an enabling pin is connected with the control end of the bidirectional DCDC converter; the voltage feedback module collects the voltage between the chargee and the chargeN and feeds back the voltage to the voltage detection pin of the control module. The switch array module adopts a modular design, each independent switch group corresponds to 6-7 strings of battery cells, and high-voltage isolation is realized through a hierarchical MOS switch structure. Abnormal channels can be automatically isolated, normal work of other modules is maintained, and the reliability and economical efficiency of the system are improved.

Description

Technical Field

[0001] This invention relates to the field of battery management system technology, and more specifically, to a distributed active balancing system. Background Technology

[0002] In active balancing circuits based on bidirectional DC-DC converters, a bidirectional DC-DC converter is typically used to transfer high-energy cells to low-energy cells to achieve battery pack balancing. This application requires a switching array to switch between charging and discharging different cells, and the switching array typically uses MOSFETs as switching elements. When the number of battery cells is large, i.e., the system voltage is high, a large number of high-voltage (Vds) MOSFETs are required. This not only increases cost but also raises the risk of failure due to the increased number of MOSFETs. Furthermore, existing active balancing systems often cannot effectively diagnose and handle MOSFET malfunctions, further limiting the system's reliability and practicality.

[0003] In implementing the embodiments of the present invention, the prior art has at least the following problems or defects: on the one hand, a large number of high-voltage MOSFETs are required under high system voltage, resulting in excessively high costs; on the other hand, the existing system cannot effectively diagnose and handle faults when MOSFETs are abnormal, affecting the reliability and safety of the system. Summary of the Invention

[0004] This invention provides a distributed active load balancing system, comprising: Switch array module, bidirectional DC-DC converter module, control module and voltage feedback module; The input terminal of the switch array module is connected to the positive terminal of multiple battery cells, and the first node of the output terminal is connected to the positive terminal of the VO terminal of the bidirectional DC-DC converter module. The second node at the output is connected to the negative terminal of the VO terminal. ; The IO pin of the control module is connected to the anode of the primary side of the optocoupler in the switch array module, and the enable pin of the control module is connected to the control terminal of the bidirectional DC-DC converter module. The first input terminal of the voltage feedback module is connected to The second input terminal is connected to The output terminal is connected to the voltage detection pin of the control module; The switch array module is divided into multiple independent switch groups, each group corresponding to six or seven strings of battery cells.

[0005] Furthermore, the switch array module includes multiple sets of switch units; Each switch unit includes a main switch submodule and branch switch submodules; The input terminal of the main switch submodule is connected to the positive terminal of the drive power supply, and the output terminal is connected to the common terminal of the branch switch submodules. The input terminal of the branch switch submodule is connected to the positive terminal of the corresponding battery cell, and the output terminal is connected to the output terminal of the main switch submodule. The grounding terminal of the main switch submodule is connected to the VO terminal. ; The grounding terminal of the switch submodule is connected to the VO terminal. .

[0006] Furthermore, the main switch submodule includes: First optocoupler U3: Its primary-side anode is connected to the first I / O pin of the control module. The primary cathode is grounded; First diode D9: Its anode is connected to the drive power supply. The cathode is connected to the first terminal of the first gate resistor R22; The first gate resistor R22: its second end is connected to the gate of the first MOS switch Q9 and the first end of the first voltage divider resistor R18; The first voltage divider resistor R18: its second terminal is connected to the VO terminal. ; The first MOS switch Q9 has its drain connected to the anode of the second diode D10, and its source connected to the VO terminal. ; The second diode D10: its cathode is connected to the first terminal of the second gate resistor R23; The second gate resistor R23: its second end is connected to the gate of the second MOS switch Q10 and the first end of the second voltage divider resistor R19; The second voltage divider resistor R19: its second end is connected to the common terminal of the switch submodule; The second MOS switch Q10: its drain serves as the output terminal of the main switch submodule, and its source is connected to the common terminal of the branch switch submodule.

[0007] Furthermore, the disconnect switch submodule includes: Second optocoupler U1: Its primary side anode is connected to the second IO pin of the control module. The primary cathode is grounded; The third diode D2: its anode is connected to the drive power supply. The cathode is connected to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2 and the first terminal of the third voltage divider resistor R2. The third voltage divider resistor R2: its second end is connected to the positive terminal of the battery cell; The third MOS switch Q2: its drain is connected to the anode of the fourth diode D1, and its source is connected to the drain of the fourth MOS switch Q1; The fourth diode D1: its cathode is connected to the first terminal of the fourth gate resistor R8; The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1 and the first terminal of the fourth voltage divider resistor R15. The fourth voltage divider resistor R15: its second terminal is connected to the VO terminal. ; The fourth MOS switch Q1: its source is connected to the VO terminal. .

[0008] Furthermore, the voltage feedback module includes: The fifth voltage divider resistor R1: its first terminal is connected to the VO terminal. The second end is connected to the first end of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The sixth voltage divider resistor R2: its second terminal is connected to the VO terminal. ; Feedback optocoupler U4: Its primary cathode is connected to the VO terminal. The collector of the secondary side is connected to the power supply VCC, and the emitter of the secondary side is connected to the voltage detection pin of the control module. .

[0009] Furthermore, the conduction path of the main switch submodule is as follows: The control module uses the first IO pin Output a high level to the primary anode of the first optocoupler U3; Drive power supply Connect the anode of the first diode D9, and connect the cathode of the first diode D9 to the first terminal of the first gate resistor R22; The second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9; The source of the first MOS switch Q9 is connected to the VO terminal. Forming a conductive loop; The drain of the first MOS switch Q9 is connected to the anode of the second diode D10, and the cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23. The second gate resistor R23 is connected to the gate of the second MOS switch Q10. The source of the second MOS switch Q10 is connected to the common terminal of the branch switch submodule to form a conduction loop.

[0010] Furthermore, the conduction path of the switch submodule is as follows: The control module uses the second IO pin. Output a high level to the primary anode of the second optocoupler U1; Drive power supply Connect the anode of the third diode D2, and connect the cathode of the third diode D2 to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2; The source of the third MOS switch Q2 is connected to the charge_N terminal of the VO terminal through the body diode of the fourth MOS switch Q1 to form an initial circuit; The drain of the third MOS switch Q2 is connected to the anode of the fourth diode D1, and the cathode of the fourth diode D1 is connected to the first terminal of the fourth gate resistor R8. The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1; The source of the fourth MOS switch Q1 is connected to the VO terminal. A conductive loop is formed.

[0011] Furthermore, the operation process of the voltage feedback module is as follows: VO terminal Connect the first terminal of the fifth voltage divider resistor R1; The second terminal of the fifth voltage divider resistor R1 is connected to the first terminal of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The second terminal of the sixth voltage divider resistor R2 is connected to the VO terminal. ; Feedback optocoupler U4 primary cathode connected to VO terminal Forming a current path; The secondary emitter of the feedback optocoupler U4 is connected to the voltage detection pin of the control module. .

[0012] Furthermore, the fault diagnosis process includes: Before turning on the MOS switch of the target cell, the control module reads the voltage detection pin level status. After the control module turns on the MOS switch of the target cell, it reads the voltage detection pin level status again. After the control module turns off the MOS switch of the target cell, it reads the voltage detection pin level for the third time. The control module determines the fault type based on the three voltage levels.

[0013] Furthermore, the fault handling mechanism is as follows: The control module records the fault switch group number when a fault is detected; The control module permanently disables all IO pin outputs corresponding to the fault group. The control module maintains the I / O pin control functions of other switch groups.

[0014] The embodiments of the present invention have at least the following beneficial effects: 1. By using a modular switch array design and a hierarchical MOS drive structure, the high-voltage battery pack balancing task is decomposed into multiple independent switch groups, which reduces the voltage stress that a single MOSFET needs to withstand. This allows the use of low-voltage, low-cost MOSFET devices, effectively solving the problem of excessively high power device costs in high-voltage battery pack balancing systems while maintaining the system's balancing performance.

[0015] 2. By adopting a three-stage voltage detection mechanism in conjunction with a feedback optocoupler circuit, the entire process of MOSFET switching status monitoring is realized. It can accurately identify various fault types such as DS breakdown, GS breakdown, and fuse blowing, solving the technical problem that traditional equalization systems have difficulty in diagnosing MOSFET failure status and improving the reliability and safety of the system.

[0016] 3. By using power supply potential isolation technology and modular redundancy design, when a fault is detected in a switch group, all IO outputs of that group can be automatically disabled without affecting the normal operation of other modules. This achieves intelligent isolation of fault channels, solves the problem of overall functional paralysis caused by local faults in traditional equalization systems, and ensures the continuous and stable operation of the system. Attached Figure Description

[0017] The above and other objects, features, and advantages of exemplary embodiments of the present invention will become readily apparent from the following detailed description taken in conjunction with the accompanying drawings. Several embodiments of the invention are illustrated in the drawings by way of example and not limitation, wherein: Figure 1 This is a schematic diagram of the structure of a distributed active load balancer system provided in an embodiment of the present invention; Figure 2 This is a schematic diagram of a voltage feedback module provided in an embodiment of the present invention. Detailed Implementation

[0018] The principles and spirit of the invention will now be described with reference to several exemplary embodiments. It should be understood that these embodiments are provided merely to enable those skilled in the art to better understand and implement the invention, and are not intended to limit the scope of the invention in any way. Rather, these embodiments are provided to make the invention more thorough and complete, and to fully convey the scope of the invention to those skilled in the art.

[0019] Those skilled in the art will recognize that embodiments of the present invention can be implemented as a system, apparatus, device, method, or computer program product. Therefore, the present invention can be specifically implemented in the following forms: entirely hardware, entirely software (including firmware, resident software, microcode, etc.), or a combination of hardware and software.

[0020] It should be noted that the number of any elements in the accompanying drawings is for illustrative purposes only and not as a limitation, and any naming is for distinction only and has no limiting meaning.

[0021] The following is for reference. Figure 1 , Figure 1 This is a schematic diagram of the structure of a distributed active load balancing system provided in an embodiment of the present invention. Figure 1 As shown, a distributed active load balancing system includes: Switch array module, bidirectional DC-DC converter module, control module and voltage feedback module; The input terminal of the switch array module is connected to the positive terminal of multiple battery cells, and the first node of the output terminal is connected to the positive terminal of the VO terminal of the bidirectional DC-DC converter module. The second node at the output is connected to the negative terminal of the VO terminal. ; The IO pin of the control module is connected to the anode of the primary side of the optocoupler in the switch array module, and the enable pin of the control module is connected to the control terminal of the bidirectional DC-DC converter module. The first input terminal of the voltage feedback module is connected to The second input terminal is connected to The output terminal is connected to the voltage detection pin of the control module; The switch array module is divided into multiple independent switch groups, each group corresponding to six or seven strings of battery cells.

[0022] It should be noted that a distributed active balancing system is a device for battery pack energy management. Its core lies in achieving energy transfer between cells within the battery pack through a switch array module and a bidirectional DC-DC converter module, thereby balancing the battery pack voltage. The switch array module consists of multiple independent switch groups, each corresponding to a set of cells, typically six or seven cells in series. This design effectively reduces system complexity and cost. The bidirectional DC-DC converter module is the key component for bidirectional energy conversion; by controlling its forward or reverse operation, it can charge or discharge the cells. The control module is responsible for the coordination and control of the entire system, using its I / O pins and enable pins to precisely control the switch array module and the bidirectional DC-DC converter module. The voltage feedback module is used to monitor the output voltage of the bidirectional DC-DC converter module in real time, ensuring the stability and safety of the system operation.

[0023] Specifically, the switch array module comprises multiple sets of switch units, each set including a master switch submodule and individual switch submodules. The input of the master switch submodule is connected to the positive terminal of the drive power supply, and its output is connected to the common terminal of the individual switch submodules. The input of each individual switch submodule is connected to the positive terminal of its corresponding battery cell, and its output is connected to the output of the master switch submodule. The ground terminal of the master switch submodule is connected to the chargeN terminal of the VO terminal, and the ground terminal of each individual switch submodule is also connected to the chargeN terminal of the VO terminal. These master and individual switch submodules are two key components of the switch array module. The master switch submodule controls the switching of the entire switch group, while the individual switch submodules control the connection status of specific battery cells. The ground terminals of both the master and individual switch submodules are connected to the negative terminal chargeN of the bidirectional DC-DC converter module to ensure circuit stability and safety. The I / O pins of the control module are connected to the switch array module via optocouplers. The optocouplers provide electrical isolation to prevent high voltage from damaging the control module. The control terminal of the bidirectional DC-DC converter module is controlled through its enable pin, thereby adjusting the direction of power conversion. The input of the voltage feedback module is connected to the outputs chargeP and chargeN of the bidirectional DC-DC converter module. The voltage signal is fed back to the voltage detection pin of the control module through voltage divider resistors and optocouplers so as to monitor the voltage status in real time.

[0024] Preferably, the conduction path of the main switch submodule is as follows: the control module outputs a high level to the anode of the primary side of the first optocoupler U3 through the first IO pin MCUIO1; the drive power supply VCCDRIVE1 is connected to the anode of the first diode D9; the cathode of the first diode D9 is connected to the first terminal of the first gate resistor R22; the second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9; and the source of the first MOS switch Q9 is connected to the chargeN terminal of VO to form a conduction loop. The drain of the first MOS switch Q9 is connected to the anode of the second diode D10; the cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23; the second terminal of the second gate resistor R23 is connected to the gate of the second MOS switch Q10; and the source of the second MOS switch Q10 is connected to the common terminal of the branch switch submodule to form a conduction loop. In actual operation, the control module outputs a high-level signal to the anode of the primary side of the optocoupler, triggering the optocoupler to conduct, thereby enabling the drive power supply to provide sufficient voltage to the gate of the MOS switch through the diode and the gate resistor, thus turning it on. This process, through a multi-stage switch design, effectively reduces the voltage that the MOS switch withstands in the off state, thereby allowing the selection of MOS transistors with lower withstand voltage and reducing system costs. Meanwhile, precise control signals and circuit design ensure the reliability and stability of the switch.

[0025] In some embodiments, the switch array module includes multiple sets of switch units; Each switch unit includes a main switch submodule and branch switch submodules; The input terminal of the main switch submodule is connected to the positive terminal of the drive power supply, and the output terminal is connected to the common terminal of the branch switch submodules. The input terminal of the branch switch submodule is connected to the positive terminal of the corresponding battery cell, and the output terminal is connected to the output terminal of the main switch submodule. The grounding terminal of the main switch submodule is connected to the VO terminal. ; The grounding terminal of the switch submodule is connected to the VO terminal. .

[0026] It should be noted that the switch array module comprises multiple sets of switch units, each set including a master switch submodule and individual switch submodules. The input terminal of the master switch submodule is connected to the positive terminal of the drive power supply, and its output terminal is connected to the common terminal of the individual switch submodules. The input terminal of each individual switch submodule is connected to the positive terminal of its corresponding battery cell, and its output terminal is connected to the output terminal of the master switch submodule. The ground terminal of the master switch submodule is connected to the chargeN terminal of the VO terminal, and the ground terminal of each individual switch submodule is also connected to the chargeN terminal of the VO terminal. This switch array module is the core component of the distributed active balancing system, used to control the connection status between different battery cells, thereby achieving energy transfer and balancing. The master switch submodule and individual switch submodules are designed to achieve group management and precise control of the battery cells. This hierarchical structure effectively reduces system complexity and improves reliability.

[0027] Specifically, the master switch submodule and branch switch submodules in the switch array module are key components for controlling the cell connection. The input terminal of the master switch submodule is connected to the positive terminal of the drive power supply, providing power input for the entire switch group. Its output terminal is connected to the common terminal of the branch switch submodules, used to transmit the state of the master switch submodule to the branch switch submodules. The input terminal of the branch switch submodule is connected to the positive terminal of the corresponding cell, and its output terminal is connected to the output terminal of the master switch submodule, used to control the connection state of the specific cell. The ground terminals of both the master switch submodule and the branch switch submodules are connected to the negative terminal (chargeN) of the bidirectional DC-DC converter module to ensure circuit stability and safety. This design, through multi-stage switching, reduces the voltage across the MOSFETs (switches down to drain) when the switches are off, allowing for the selection of MOSFETs with lower voltage ratings and reducing system costs. Simultaneously, the coordinated operation of the master switch submodule and the branch switch submodules enables precise control of the cells, ensuring stable system operation under various conditions.

[0028] Preferably, the specific implementation of the main switch submodule and the branch switch submodules of the switch array module can be further refined. For example, the main switch submodule can be connected to the control module via an optocoupler. The optocoupler provides electrical isolation to prevent high voltage from damaging the control module. The control module outputs a high-level signal to the primary anode of the optocoupler, triggering the optocoupler to conduct. This, in turn, allows the drive power supply to provide sufficient voltage to the gate of the MOS switch through the diode and gate resistor, enabling it to conduct. The branch switch submodules control specific battery cells using a similar circuit structure. In practical applications, the parameters of the main switch submodule and the branch switch submodules, such as the withstand voltage and on-resistance of the MOS transistors, can be flexibly selected according to the voltage level and number of battery cells in the battery pack to ensure efficient operation and reliability of the system. Furthermore, by optimizing the circuit design, switching losses can be further reduced, improving the system's energy conversion efficiency.

[0029] In some embodiments, the main switch submodule includes: First optocoupler U3: Its primary-side anode is connected to the first I / O pin of the control module. The primary cathode is grounded; First diode D9: Its anode is connected to the drive power supply. The cathode is connected to the first terminal of the first gate resistor R22; The first gate resistor R22: its second end is connected to the gate of the first MOS switch Q9 and the first end of the first voltage divider resistor R18; The first voltage divider resistor R18: its second terminal is connected to the VO terminal. ; The first MOS switch Q9 has its drain connected to the anode of the second diode D10, and its source connected to the VO terminal. ; The second diode D10: its cathode is connected to the first terminal of the second gate resistor R23; The second gate resistor R23: its second end is connected to the gate of the second MOS switch Q10 and the first end of the second voltage divider resistor R19; The second voltage divider resistor R19: its second end is connected to the common terminal of the switch submodule; The second MOS switch Q10: its drain serves as the output terminal of the main switch submodule, and its source is connected to the common terminal of the branch switch submodule.

[0030] It should be noted that the main switch submodule is designed to control the on / off state of the battery cell array within the switch array module. Its circuit structure includes components such as optocouplers, diodes, gate resistors, voltage divider resistors, and MOS switches. These components, through specific connection methods, ensure that the main switch submodule can reliably turn on or off under the command of the control module. The optocoupler provides electrical isolation for the control signal, preventing high voltage from damaging the control module; the MOS switch is the core component for controlling the on / off state of the battery cell array. Through this design, the main switch submodule can effectively reduce the voltage stress on the battery cell array even with low-voltage MOS switches, thereby reducing costs and improving system reliability.

[0031] Specifically, the circuit structure of the master switch submodule includes the following key components and their functions: The primary-side anode of the first optocoupler U3 is connected to the first IO pin MCUIO1 of the control module for receiving control signals; the primary-side cathode is grounded to ensure stable signal transmission. The anode of the first diode D9 is connected to the drive power supply VCCDRIVE1, and the cathode is connected to the first terminal of the first gate resistor R22 for providing a bias voltage to the gate of the MOS switch. The second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9 and the first terminal of the first voltage divider resistor R18 for limiting the gate current and providing a stable gate voltage. The second terminal of the first voltage divider resistor R18 is connected to the chargeN terminal of VO for providing a stable reference potential. The drain of the first MOS switch Q9 is connected to the anode of the second diode D10, and the source is connected to the chargeN terminal of VO for implementing the on / off control of the battery pack. The cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23. The second terminal of the second gate resistor R23 is connected to the gate of the second MOS switch Q10 and the first terminal of the second voltage divider resistor R19. The second terminal of the second voltage divider resistor R19 is connected to the common terminal of the branch switch submodule. The drain of the second MOS switch Q10 serves as the output terminal of the master switch submodule, and its source is connected to the common terminal of the branch switch submodule. This connection method ensures that the master switch submodule can reliably control the on / off state of the battery pack under the action of the control signal.

[0032] Preferably, the operation process of the master switch submodule can be further refined into the following steps: First, the control module outputs a high-level signal to the primary anode of the first optocoupler U3 through the first IO pin MCUIO1, triggering the optocoupler to conduct. At this time, the drive power supply VCCDRIVE1 provides sufficient voltage to the gate of the first MOS switch Q9 through the first diode D9 and the first gate resistor R22, enabling it to conduct. After the first MOS switch Q9 conducts, the current provides voltage to the gate of the second MOS switch Q10 through the second diode D10 and the second gate resistor R23, enabling it to conduct. Finally, the current is output through the drain of the second MOS switch Q10, completing the conduction path of the master switch submodule. In practical applications, appropriate parameters for the optocoupler, diode, gate resistor, and MOS switch can be selected according to the voltage and current requirements of the battery pack. For example, the isolation voltage of the optocoupler should be higher than the operating voltage of the system, the withstand voltage of the MOS switch should meet the voltage requirements of the battery pack, and the resistance value of the gate resistor should be optimized according to the gate drive current of the MOS switch to ensure the stability and reliability of the system. Furthermore, by properly designing the resistance values ​​of the voltage divider resistors, the gate voltage can be precisely controlled, further improving the system performance.

[0033] In some embodiments, the disconnector submodule includes: Second optocoupler U1: Its primary side anode is connected to the second IO pin of the control module. The primary cathode is grounded; The third diode D2: its anode is connected to the drive power supply. The cathode is connected to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2 and the first terminal of the third voltage divider resistor R2. The third voltage divider resistor R2: its second end is connected to the positive terminal of the battery cell; The third MOS switch Q2: its drain is connected to the anode of the fourth diode D1, and its source is connected to the drain of the fourth MOS switch Q1; The fourth diode D1: its cathode is connected to the first terminal of the fourth gate resistor R8; The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1 and the first terminal of the fourth voltage divider resistor R15. The fourth voltage divider resistor R15: its second terminal is connected to the VO terminal. ; The fourth MOS switch Q1: its source is connected to the VO terminal. .

[0034] It should be noted that the splitter submodule is designed to achieve precise control of individual battery cells. Its circuit structure includes components such as optocouplers, diodes, gate resistors, voltage divider resistors, and MOS switches. These components, through specific connection methods, ensure that the splitter submodule can reliably conduct or cut off under the command of the control module. The optocoupler provides electrical isolation for the control signal, preventing high voltage from damaging the control module; the MOS switch is the core component for controlling the switching of the battery cells. Through this design, the splitter submodule can effectively reduce the voltage stress on the battery cells even with low-voltage MOS switches, thereby reducing costs and improving system reliability.

[0035] Specifically, the circuit structure of the splitter submodule includes the following key components and their functions: The primary anode of the second optocoupler U1 is connected to the second IO pin MCUIO2 of the control module to receive control signals; the primary cathode is grounded to ensure stable signal transmission. The anode of the third diode D2 is connected to the drive power supply VCCDRIVE1, and the cathode is connected to the first terminal of the third gate resistor R5 to provide a bias voltage for the gate of the MOS switch. The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2 and the first terminal of the third voltage divider resistor R2 to limit the gate current and provide a stable gate voltage. The second terminal of the third voltage divider resistor R2 is connected to the positive terminal of the battery cell to provide a stable reference potential. The drain of the third MOS switch Q2 is connected to the anode of the fourth diode D1, and the source is connected to the drain of the fourth MOS switch Q1 to realize the on / off control of the battery cell. The cathode of the fourth diode D1 is connected to the first terminal of the fourth gate resistor R8. The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1 and the first terminal of the fourth voltage divider resistor R15. The second terminal of the fourth voltage divider resistor R15 is connected to the chargeN terminal of VO. The source of the fourth MOS switch Q1 is connected to the chargeN terminal of VO. This connection method ensures that the switch submodule can reliably control the on / off state of the battery cell under the action of the control signal.

[0036] Preferably, the operation process of the splitter submodule can be further refined into the following steps: First, the control module outputs a high-level signal to the primary anode of the second optocoupler U1 through the second IO pin MCUIO2, triggering the optocoupler to conduct. At this time, the drive power supply VCCDRIVE1 provides sufficient voltage to the gate of the third MOS switch Q2 through the third diode D2 and the third gate resistor R5, enabling it to conduct. After the third MOS switch Q2 conducts, the current provides voltage to the gate of the fourth MOS switch Q1 through the fourth diode D1 and the fourth gate resistor R8, enabling it to conduct. Finally, the current returns to the chargeN terminal of VO through the source of the fourth MOS switch Q1, completing the conduction path of the splitter submodule. In practical applications, appropriate parameters for the optocoupler, diode, gate resistor, and MOS switch can be selected according to the voltage and current requirements of the battery cell. For example, the isolation voltage of the optocoupler should be higher than the operating voltage of the system, the withstand voltage of the MOS switch should meet the voltage requirements of the battery cell, and the resistance value of the gate resistor should be optimized according to the gate drive current of the MOS switch to ensure the stability and reliability of the system. Furthermore, by properly designing the resistance values ​​of the voltage divider resistors, the gate voltage can be precisely controlled, further improving the system performance.

[0037] like Figure 2 As shown, in some embodiments, the voltage feedback module includes: The fifth voltage divider resistor R1: its first terminal is connected to the VO terminal. The second end is connected to the first end of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The sixth voltage divider resistor R2: its second terminal is connected to the VO terminal. ; Feedback optocoupler U4: Its primary cathode is connected to the VO terminal. The collector of the secondary side is connected to the power supply VCC, and the emitter of the secondary side is connected to the voltage detection pin of the control module. .

[0038] It should be noted that the voltage feedback module is a crucial component of the distributed active balancing system. Its main function is to monitor the output voltage of the bidirectional DC-DC converter module in real time and feed this voltage information back to the control module. Through this feedback mechanism, the control module can dynamically adjust the system based on the actual voltage conditions, ensuring the stability and safety of the active balancing process. The core of the voltage feedback module lies in using voltage divider resistors and optocouplers to achieve voltage signal acquisition and isolated transmission, thereby providing the control module with an accurate voltage detection signal.

[0039] Specifically, the voltage feedback module's circuit structure includes a fifth voltage-dividing resistor R1, a sixth voltage-dividing resistor R2, and a feedback optocoupler U4. The first terminal of the fifth voltage-dividing resistor R1 is connected to the chargeP terminal of the bidirectional DC-DC converter module for initial voltage division of the output voltage; its second terminal is connected to the first terminal of the sixth voltage-dividing resistor R2 and the anode of the primary side of the feedback optocoupler U4. The second terminal of the sixth voltage-dividing resistor R2 is connected to the chargeN terminal of the bidirectional DC-DC converter module for further voltage division and stabilizing the feedback signal. The cathode of the primary side of the feedback optocoupler U4 is connected to the chargeN terminal to convert the divided voltage signal into an optical signal for isolated transmission; its secondary collector is connected to the power supply VCC, and its secondary emitter is connected to the voltage detection pin MCUDETECT of the control module. This design reduces the high-voltage signal to a suitable level range for optocoupler transmission through the voltage-dividing resistors, while utilizing the isolation characteristics of the optocoupler to prevent high voltage from damaging the control module, ensuring the system's reliability and safety.

[0040] Preferably, the operation of the voltage feedback module can be further refined into the following steps: First, the output voltage of the bidirectional DC-DC converter module is connected to the first terminal of the fifth voltage divider resistor R1 through the chargeP terminal. Through the voltage division effect of R1 and R2, the high-voltage signal is reduced to a level suitable for optocoupler transmission. Then, the divided voltage signal is input through the anode of the primary side of the feedback optocoupler U4, and the cathode is connected to the chargeN terminal, forming a current path. The optocoupler converts the electrical signal into an optical signal and restores the optical signal to an electrical signal on the secondary side, outputting it through the emitter of the secondary side to the voltage detection pin MCUDETECT of the control module. The control module determines the operating state of the bidirectional DC-DC converter module based on the detected voltage signal and performs corresponding control operations accordingly. In practical applications, a suitable voltage divider resistor value can be selected according to the system's operating voltage range to ensure that the divided voltage signal can accurately trigger the optocoupler. Simultaneously, the isolation voltage and transmission characteristics of the optocoupler should meet the system requirements to ensure the accuracy and reliability of the feedback signal. With this design, the voltage feedback module can feed back the output voltage of the bidirectional DC-DC converter module to the control module in real time and accurately, providing an important guarantee for the stable operation of the system.

[0041] In some embodiments, the conduction path of the main switch submodule is as follows: The control module uses the first IO pin Output a high level to the primary anode of the first optocoupler U3; Drive power supply Connect the anode of the first diode D9, and connect the cathode of the first diode D9 to the first terminal of the first gate resistor R22; The second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9; The source of the first MOS switch Q9 is connected to the VO terminal. Forming a conductive loop; The drain of the first MOS switch Q9 is connected to the anode of the second diode D10, and the cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23. The second gate resistor R23 is connected to the gate of the second MOS switch Q10. The source of the second MOS switch Q10 is connected to the common terminal of the branch switch submodule to form a conduction loop.

[0042] It should be noted that the conduction path of the main switch submodule is achieved by the control module outputting a high-level signal, which passes through components such as optocouplers, diodes, and gate resistors, ultimately turning on the MOS switch. This process establishes a current path from the drive power supply to the battery cell, ensuring that the battery cell can be correctly connected to the bidirectional DC-DC converter module for charging and discharging operations. The conduction path design is based on the electrical isolation and signal transmission requirements of the circuit. Through reasonable component layout and parameter selection, stable signal transmission and reliable switch conduction are ensured.

[0043] Specifically, the conduction path of the master switch submodule involves the following key components and their functions: The primary anode of the first optocoupler U3 is connected to the first IO pin MCUIO1 of the control module to receive high-level signals from the control module; the primary cathode is grounded to form a complete signal loop. The anode of the first diode D9 is connected to the drive power supply VCCDRIVE1, and the cathode is connected to the first terminal of the first gate resistor R22 to prevent reverse current and provide a stable voltage source for the gate resistor. The second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9 and the first terminal of the first voltage divider resistor R18 to limit the gate current and provide a stable gate voltage. The second terminal of the first voltage divider resistor R18 is connected to the chargeN terminal of VO to provide a stable reference potential. The drain of the first MOS switch Q9 is connected to the anode of the second diode D10, and the source is connected to the chargeN terminal of VO to realize the on / off control of the battery cell. The cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23. The second terminal of the second gate resistor R23 is connected to the gate of the second MOS switch Q10 and the first terminal of the second voltage divider resistor R19. The second terminal of the second voltage divider resistor R19 is connected to the common terminal of the branch switch submodule. The drain of the second MOS switch Q10 serves as the output terminal of the master switch submodule, and its source is connected to the common terminal of the branch switch submodule. The coordinated operation of these components ensures that the master switch submodule can reliably conduct under the action of the control signal.

[0044] Preferably, the conduction path operation of the main switch submodule can be further refined into the following steps: First, the control module outputs a high-level signal to the primary anode of the first optocoupler U3 through the first IO pin MCUIO1, triggering the optocoupler to conduct. At this time, the drive power supply VCCDRIVE1 provides sufficient voltage to the gate of the first MOS switch Q9 through the first diode D9 and the first gate resistor R22, enabling it to conduct. After the first MOS switch Q9 conducts, the current provides voltage to the gate of the second MOS switch Q10 through the second diode D10 and the second gate resistor R23, enabling it to conduct. Finally, the current is output through the drain of the second MOS switch Q10, completing the conduction path of the main switch submodule. In practical applications, appropriate parameters for the optocoupler, diode, gate resistor, and MOS switch can be selected according to the voltage and current requirements of the battery cell. For example, the isolation voltage of the optocoupler should be higher than the operating voltage of the system, the withstand voltage of the MOS switch should meet the voltage requirements of the battery cell, and the resistance value of the gate resistor should be optimized according to the gate drive current of the MOS switch to ensure the stability and reliability of the system. Furthermore, by properly designing the resistance values ​​of the voltage divider resistors, the gate voltage can be precisely controlled, further improving the system performance.

[0045] In some embodiments, the conduction path of the switch submodule is as follows: The control module uses the second IO pin. Output a high level to the primary anode of the second optocoupler U1; Drive power supply Connect the anode of the third diode D2, and connect the cathode of the third diode D2 to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2; The source of the third MOS switch Q2 is connected to the charge_N terminal of the VO terminal through the body diode of the fourth MOS switch Q1 to form an initial circuit; The drain of the third MOS switch Q2 is connected to the anode of the fourth diode D1, and the cathode of the fourth diode D1 is connected to the first terminal of the fourth gate resistor R8. The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1; The source of the fourth MOS switch Q1 is connected to the VO terminal. A conductive loop is formed.

[0046] It should be noted that the conduction path of the switch submodule is achieved by the control module outputting a high-level signal, which passes through components such as optocouplers, diodes, and gate resistors, ultimately turning on the MOS switch. This process establishes a current path from the battery cell to the bidirectional DC-DC converter module, ensuring that the battery cell can be correctly connected to the bidirectional DC-DC converter module for charging and discharging operations. The conduction path design of the switch submodule is based on the electrical isolation and signal transmission requirements of the circuit. Through reasonable component layout and parameter selection, stable signal transmission and reliable switch conduction are ensured.

[0047] Specifically, the conduction path of the switch submodule involves the following key components and their functions: The primary anode of the second optocoupler U1 is connected to the second IO pin MCUIO2 of the control module to receive high-level signals from the control module; the primary cathode is grounded to form a complete signal loop. The anode of the third diode D2 is connected to the drive power supply VCCDRIVE1, and the cathode is connected to the first terminal of the third gate resistor R5 to prevent reverse current and provide a stable voltage source for the gate resistor. The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2 and the first terminal of the third voltage divider resistor R2 to limit the gate current and provide a stable gate voltage. The second terminal of the third voltage divider resistor R2 is connected to the positive terminal of the battery cell to provide a stable reference potential. The drain of the third MOS switch Q2 is connected to the anode of the fourth diode D1, and the source is connected to the drain of the fourth MOS switch Q1 to realize the on / off control of the battery cell. The cathode of the fourth diode D1 is connected to the first terminal of the fourth gate resistor R8. The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1 and the first terminal of the fourth voltage divider resistor R15. The second terminal of the fourth voltage divider resistor R15 is connected to the chargeN terminal of VO. The source of the fourth MOS switch Q1 is connected to the chargeN terminal of VO. The coordinated operation of these components ensures that the switch submodule can be reliably turned on under the action of the control signal.

[0048] Preferably, the conduction path operation of the splitter submodule can be further refined into the following steps: First, the control module outputs a high-level signal to the primary anode of the second optocoupler U1 through the second IO pin MCUIO2, triggering the optocoupler to conduct. At this time, the drive power supply VCCDRIVE1 provides sufficient voltage to the gate of the third MOS switch Q2 through the third diode D2 and the third gate resistor R5, enabling it to conduct. After the third MOS switch Q2 conducts, the current provides voltage to the gate of the fourth MOS switch Q1 through the fourth diode D1 and the fourth gate resistor R8, enabling it to conduct. Finally, the current returns to the chargeN terminal of VO through the source of the fourth MOS switch Q1, completing the conduction path of the splitter submodule. In practical applications, appropriate parameters for the optocoupler, diode, gate resistor, and MOS switch can be selected according to the voltage and current requirements of the battery cell. For example, the isolation voltage of the optocoupler should be higher than the operating voltage of the system, the withstand voltage of the MOS switch should meet the voltage requirements of the battery cell, and the resistance value of the gate resistor should be optimized according to the gate drive current of the MOS switch to ensure the stability and reliability of the system. Furthermore, by properly designing the resistance values ​​of the voltage divider resistors, the gate voltage can be precisely controlled, further improving the system performance.

[0049] In some embodiments, the voltage feedback module operates as follows: VO terminal Connect the first terminal of the fifth voltage divider resistor R1; The second terminal of the fifth voltage divider resistor R1 is connected to the first terminal of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The second terminal of the sixth voltage divider resistor R2 is connected to the VO terminal. ; Feedback optocoupler U4 primary cathode connected to VO terminal Forming a current path; The secondary emitter of the feedback optocoupler U4 is connected to the voltage detection pin of the control module. .

[0050] It should be noted that the voltage feedback module works by converting the output voltage of the bidirectional DC-DC converter module into a signal suitable for the control module to detect through voltage divider resistors and optocouplers. This process ensures that the control module can monitor the output voltage status of the bidirectional DC-DC converter module in real time, thereby achieving precise control of the system's operating status and fault diagnosis. The voltage feedback module is designed based on the voltage divider principle and the electrical isolation characteristics of optocouplers. Through reasonable circuit design, it achieves safe conversion and transmission of high-voltage signals to low-voltage signals.

[0051] Specifically, the operation of the voltage feedback module involves the following key components and their functions: The first terminal of the fifth voltage-dividing resistor R1 is connected to the chargeP terminal of the bidirectional DC-DC converter module, used for initial voltage division of the output voltage; its second terminal is connected to the first terminal of the sixth voltage-dividing resistor R2 and the anode of the primary side of the feedback optocoupler U4. The second terminal of the sixth voltage-dividing resistor R2 is connected to the chargeN terminal of the bidirectional DC-DC converter module, used for further voltage division and stabilizing the feedback signal. The cathode of the primary side of the feedback optocoupler U4 is connected to the chargeN terminal, used to convert the divided voltage signal into an optical signal for isolated transmission; its secondary collector is connected to the power supply VCC, and its secondary emitter is connected to the voltage detection pin MCUDETECT of the control module. In this process, the resistance values ​​of the voltage-dividing resistors R1 and R2 determine the voltage division ratio, while the isolation voltage and transmission characteristics of the optocoupler U4 ensure the safe and accurate transmission of the signal.

[0052] Preferably, the operation of the voltage feedback module can be further refined into the following steps: First, the output voltage of the bidirectional DC-DC converter module is input to the first terminal of the fifth voltage divider resistor R1 through the chargeP terminal. After voltage division by R1 and R2, the high voltage signal is reduced to a level suitable for optocoupler transmission. Subsequently, the voltage signal after voltage division is input through the anode of the primary side of the feedback optocoupler U4, and the cathode of the primary side is connected to the chargeN terminal, forming a current path. The optocoupler converts the electrical signal into an optical signal, and then converts the optical signal back into an electrical signal on the secondary side, outputting it to the voltage detection pin MCUDETECT of the control module through the emitter of the secondary side. The control module determines the operating state of the bidirectional DC-DC converter module based on the detected voltage signal and performs corresponding control operations accordingly. In practical applications, an appropriate voltage divider resistor value can be selected according to the operating voltage range of the system to ensure that the voltage signal after voltage division can accurately trigger the optocoupler. At the same time, the isolation voltage and transmission characteristics of the optocoupler should meet the system requirements to ensure the accuracy and reliability of the feedback signal. With this design, the voltage feedback module can feed back the output voltage of the bidirectional DC-DC converter module to the control module in real time and accurately, providing an important guarantee for the stable operation of the system.

[0053] In some embodiments, the fault diagnosis process includes: Before turning on the MOS switch of the target cell, the control module reads the voltage detection pin level status. After the control module turns on the MOS switch of the target cell, it reads the voltage detection pin level status again. After the control module turns off the MOS switch of the target cell, it reads the voltage detection pin level for the third time. The control module determines the fault type based on the three voltage levels.

[0054] It should be noted that the fault diagnosis process is a crucial step in the distributed active balancing system for detecting and determining fault types. This process involves the control module reading the voltage detection pin's level at different stages of turning the target cell's MOS switch on and off, thereby determining the fault type. This process utilizes real-time voltage information provided by the voltage feedback module, combined with the control module's logical judgment, to achieve rapid fault diagnosis. The fault diagnosis process is designed based on the voltage feedback mechanism and the control module's logical control capabilities, ensuring the accuracy and reliability of fault diagnosis through multiple level readings.

[0055] Specifically, the fault diagnosis process involves the following key steps and parameters: Before turning on the target cell's MOS switch, the control module reads the voltage detection pin's level. Theoretically, there should be no voltage feedback at this point because the cell is not yet connected to the bidirectional DC-DC converter module. After turning on the target cell's MOS switch, the control module reads the voltage detection pin's level again. Theoretically, there should be voltage feedback at this point because the cell is now connected to the bidirectional DC-DC converter module. After turning off the target cell's MOS switch, the control module reads the voltage detection pin's level a third time. Theoretically, there should be no voltage feedback at this point because the cell has been disconnected from the bidirectional DC-DC converter module. Through these three level readings, the control module can determine the fault type. For example, if voltage feedback is detected before turning on the MOS switch, it may indicate that the power module was mistakenly turned on or the MOS transistor was short-circuited. If no voltage feedback is detected after turning on the MOS switch, it may indicate that the MOS transistor is not conducting properly or the fuse is blown. These judgments are based on the real-time voltage information provided by the voltage feedback module and the control module's logical analysis of the level status.

[0056] Preferably, the fault diagnosis process can be further refined as follows: First, before the system prepares to perform equalization on a specific cell, the control module reads the initial voltage level through the voltage detection pin to ensure the system is in normal standby mode. Then, the control module outputs a high-level signal through the IO pin to turn on the MOS switch of the target cell and immediately reads the voltage detection pin again to confirm whether the MOS switch is successfully turned on. If the expected voltage feedback is not detected at this time, the control module records the fault information and takes corresponding fault handling measures. After completing the equalization operation, the control module turns off the MOS switch of the target cell and reads the voltage detection pin a third time to confirm whether the MOS switch is successfully turned off. Through this multiple detection method, the control module can accurately determine the fault type and take corresponding handling measures, such as recording fault information or disabling fault channels. In practical applications, the logic judgment threshold and fault handling strategy of the control module can be adjusted according to the specific needs of the system and the characteristics of the cell to improve the reliability and safety of the system.

[0057] In some embodiments, the fault handling mechanism is as follows: The control module records the fault switch group number when a fault is detected; The control module permanently disables all IO pin outputs corresponding to the fault group. The control module maintains the I / O pin control functions of other switch groups.

[0058] It should be noted that the fault handling mechanism is a series of measures taken by the distributed active load balancer system after detecting a fault, aiming to isolate the fault and ensure the safe operation of the system. This mechanism records the faulty switch group number through the control module and permanently disables all I / O pin outputs corresponding to the faulty group, while maintaining the normal function of other switch groups. This approach avoids the impact of the fault on the system while ensuring the normal operation of other parts of the system, thus improving the system's reliability and fault tolerance.

[0059] Specifically, the fault handling mechanism involves the following key steps and parameters: When the control module detects a fault, it records the faulty switch group number. This step is to pinpoint the exact location of the fault, facilitating subsequent maintenance and diagnosis. Subsequently, the control module permanently disables all IO pin outputs corresponding to the faulty group. This measure prevents further fault propagation and ensures the faulty group does not cause further impact on the system. Simultaneously, the control module maintains the IO pin control functions of other switch groups, meaning the system can still operate normally, only the faulty portion is isolated. Here, the faulty switch group number refers to the number of multiple independent switch groups divided within the system's switch array module. Each switch group corresponds to a set of battery cells, and the fault location can be quickly identified through these numbers. IO pin outputs refer to the signal outputs used by the control module to control the on / off state of the MOS switches in the switch array module. Disabling these outputs cuts off the control signals for the faulty group, preventing it from continuing to operate.

[0060] Preferably, the fault handling mechanism can be further refined into the following steps: First, when the control module determines that a certain switch group is faulty through the fault diagnosis process, it immediately records the switch group number and stores the fault information in the system's fault log for subsequent analysis and maintenance. Then, the control module sends a command to permanently disable all IO pin outputs corresponding to the faulty group. This process is implemented through software logic to ensure that the MOS switches of the faulty group are no longer falsely triggered. Simultaneously, the control module checks the status of other switch groups to ensure that their IO pin control functions are unaffected and continue to operate normally. In practical applications, a fault alarm mechanism can be designed according to the specific needs of the system, such as issuing fault warnings to users via indicator lights or communication interfaces. Furthermore, to further improve the system's fault tolerance, redundant switch groups can be designed in the system. When a switch group fails, it can automatically switch to the redundant group to ensure uninterrupted system operation. Through this fault handling mechanism, the distributed active balancing system can quickly take measures after detecting a fault, isolate the fault, and maintain the normal operation of the system, thereby improving the system's reliability and security.

[0061] The above embodiments of the present invention have the following beneficial effects: 1. By using a modular switch array design and a hierarchical MOS drive structure, the high-voltage battery pack balancing task is decomposed into multiple independent switch groups, which reduces the voltage stress that a single MOSFET needs to withstand. This allows the use of low-voltage, low-cost MOSFET devices, effectively solving the problem of excessively high power device costs in high-voltage battery pack balancing systems while maintaining the system's balancing performance.

[0062] 2. By adopting a three-stage voltage detection mechanism in conjunction with a feedback optocoupler circuit, the entire process of MOSFET switching status monitoring is realized. It can accurately identify various fault types such as DS breakdown, GS breakdown, and fuse blowing, solving the technical problem that traditional equalization systems have difficulty in diagnosing MOSFET failure status and improving the reliability and safety of the system.

[0063] 3. By using power supply potential isolation technology and modular redundancy design, when a fault is detected in a switch group, all IO outputs of that group can be automatically disabled without affecting the normal operation of other modules. This achieves intelligent isolation of fault channels, solves the problem of overall functional paralysis caused by local faults in traditional equalization systems, and ensures the continuous and stable operation of the system.

[0064] Furthermore, the storage medium in the embodiments of this application stores program instructions capable of implementing all the above methods. These program instructions can be stored in the storage medium in the form of a software product, including several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) or processor to execute all or part of the steps of the methods described in the various embodiments of this application. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, portable hard drives, read-only memory (ROM), random access memory (RAM), magnetic disks, or optical disks, or terminal devices such as computers, servers, mobile phones, and tablets.

[0065] The above description is merely an explanation of some preferred embodiments of the present invention and the technical principles employed. Those skilled in the art should understand that the scope of the invention as described in the embodiments of the present invention is not limited to technical solutions formed by specific combinations of the above-described technical features, but should also cover other technical solutions formed by arbitrary combinations of the above-described technical features or their equivalents without departing from the above-described inventive concept. For example, technical solutions formed by substituting the above-described features with (but not limited to) technical features with similar functions disclosed in the embodiments of the present invention.

Claims

1. A distributed active load balancing system, characterized in that, It includes a switch array module, a bidirectional DC-DC converter module, a control module, and a voltage feedback module; The input terminal of the switch array module is connected to the positive terminal of multiple battery cells, and the first node of the output terminal is connected to the positive terminal of the VO terminal of the bidirectional DC-DC converter module. The second node at the output is connected to the negative terminal of the VO terminal. ; The IO pin of the control module is connected to the anode of the primary side of the optocoupler in the switch array module, and the enable pin of the control module is connected to the control terminal of the bidirectional DC-DC converter module. The first input terminal of the voltage feedback module is connected to The second input terminal is connected to The output terminal is connected to the voltage detection pin of the control module; The switch array module is divided into multiple independent switch groups, each group corresponding to six or seven strings of battery cells.

2. The system according to claim 1, characterized in that, The switch array module includes multiple sets of switch units; Each switch unit includes a main switch submodule and branch switch submodules; The input terminal of the main switch submodule is connected to the positive terminal of the drive power supply, and the output terminal is connected to the common terminal of the branch switch submodules. The input terminal of the branch switch submodule is connected to the positive terminal of the corresponding battery cell, and the output terminal is connected to the output terminal of the main switch submodule. The grounding terminal of the main switch submodule is connected to the VO terminal. ; The grounding terminal of the switch submodule is connected to the VO terminal. .

3. The system according to claim 2, characterized in that, The master switch submodule includes: First optocoupler U3: Its primary-side anode is connected to the first I / O pin of the control module. The primary cathode is grounded; First diode D9: Its anode is connected to the drive power supply. The cathode is connected to the first terminal of the first gate resistor R22; The first gate resistor R22: its second end is connected to the gate of the first MOS switch Q9 and the first end of the first voltage divider resistor R18; The first voltage divider resistor R18: its second terminal is connected to the VO terminal. ; The first MOS switch Q9 has its drain connected to the anode of the second diode D10, and its source connected to the VO terminal. ; The second diode D10: its cathode is connected to the first terminal of the second gate resistor R23; The second gate resistor R23: its second end is connected to the gate of the second MOS switch Q10 and the first end of the second voltage divider resistor R19; The second voltage divider resistor R19: its second end is connected to the common terminal of the switch submodule; The second MOS switch Q10: its drain serves as the output terminal of the main switch submodule, and its source is connected to the common terminal of the branch switch submodule.

4. The system according to claim 2, characterized in that, The switch submodule includes: Second optocoupler U1: Its primary side anode is connected to the second IO pin of the control module. The primary cathode is grounded; The third diode D2: its anode is connected to the drive power supply. The cathode is connected to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2 and the first terminal of the third voltage divider resistor R2. The third voltage divider resistor R2: its second end is connected to the positive terminal of the battery cell; The third MOS switch Q2: its drain is connected to the anode of the fourth diode D1, and its source is connected to the drain of the fourth MOS switch Q1; The fourth diode D1: its cathode is connected to the first terminal of the fourth gate resistor R8; The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1 and the first terminal of the fourth voltage divider resistor R15. The fourth voltage divider resistor R15: its second terminal is connected to the VO terminal. ; The fourth MOS switch Q1: its source is connected to the VO terminal. .

5. The system according to claim 1, characterized in that, The voltage feedback module includes: The fifth voltage divider resistor R1: its first terminal is connected to the VO terminal. The second end is connected to the first end of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The sixth voltage divider resistor R2: its second terminal is connected to the VO terminal. ; Feedback optocoupler U4: Its primary cathode is connected to the VO terminal. The collector of the secondary side is connected to the power supply VCC, and the emitter of the secondary side is connected to the voltage detection pin of the control module. .

6. The system according to claim 3, characterized in that, The conduction path of the main switch submodule is as follows: The control module uses the first IO pin Output a high level to the primary anode of the first optocoupler U3; Drive power supply Connect the anode of the first diode D9, and connect the cathode of the first diode D9 to the first terminal of the first gate resistor R22; The second terminal of the first gate resistor R22 is connected to the gate of the first MOS switch Q9; The source of the first MOS switch Q9 is connected to the VO terminal. Forming a conductive loop; The drain of the first MOS switch Q9 is connected to the anode of the second diode D10, and the cathode of the second diode D10 is connected to the first terminal of the second gate resistor R23. The second gate resistor R23 is connected to the gate of the second MOS switch Q10. The source of the second MOS switch Q10 is connected to the common terminal of the branch switch submodule to form a conduction loop.

7. The system according to claim 4, characterized in that, The conduction path of the switch submodule is as follows: The control module uses the second IO pin. Output a high level to the primary anode of the second optocoupler U1; Drive power supply Connect the anode of the third diode D2, and connect the cathode of the third diode D2 to the first terminal of the third gate resistor R5; The second terminal of the third gate resistor R5 is connected to the gate of the third MOS switch Q2; The source of the third MOS switch Q2 is connected to the charge_N terminal of the VO terminal through the body diode of the fourth MOS switch Q1 to form an initial circuit; The drain of the third MOS switch Q2 is connected to the anode of the fourth diode D1, and the cathode of the fourth diode D1 is connected to the first terminal of the fourth gate resistor R8. The second terminal of the fourth gate resistor R8 is connected to the gate of the fourth MOS switch Q1; The source of the fourth MOS switch Q1 is connected to the VO terminal. A conductive loop is formed.

8. The system according to claim 5, characterized in that, The voltage feedback module operates as follows: VO terminal Connect the first terminal of the fifth voltage divider resistor R1; The second terminal of the fifth voltage divider resistor R1 is connected to the first terminal of the sixth voltage divider resistor R2 and the anode of the primary side of the feedback optocoupler U4; The second terminal of the sixth voltage divider resistor R2 is connected to the VO terminal. ; Feedback optocoupler U4 primary cathode connected to VO terminal Forming a current path; The secondary emitter of the feedback optocoupler U4 is connected to the voltage detection pin of the control module. .

9. The system according to claim 1, characterized in that, The fault diagnosis process includes: Before turning on the MOS switch of the target cell, the control module reads the voltage detection pin level status. After the control module turns on the MOS switch of the target cell, it reads the voltage detection pin level status again. After the control module turns off the MOS switch of the target cell, it reads the voltage detection pin level for the third time. The control module determines the fault type based on the three voltage levels.

10. The system according to claim 9, characterized in that, The fault handling mechanism is as follows: The control module records the fault switch group number when a fault is detected; The control module permanently disables all IO pin outputs corresponding to the fault group. The control module maintains the I / O pin control functions of other switch groups.

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