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DE-112024003127-T5 - CIRCUITS, BATTERY MANAGEMENT SYSTEM AND ELECTRIC VEHICLE

DE112024003127T5DE 112024003127 T5DE112024003127 T5DE 112024003127T5DE-112024003127-T5

Abstract

The present application relates to a circuit, a battery management system, and an electric vehicle. The circuit comprises a first current sensing module, a second current sensing module, and a calculation module. The first and second current sensing modules are connected in series in the main circuit and the control circuit, respectively, of the battery management system. The calculation module is configured to calculate the state of charge (SOC) of the battery management system based on the first current information acquired by the first current sensing module and the second current information acquired by the second current sensing module.

Inventors

  • Zhen Liu
  • Wenbing XIAO
  • Shaowei XIE
  • LIPING WAN

Assignees

  • EVE ENERGY CO., LTD.

Dates

Publication Date
20260513
Application Date
20240826
Priority Date
20230825

Claims (20)

  1. A state-of-charge (SOC) sensing circuit of a battery management system, comprising: a first current sensing module (101) connected in series in a main circuit (300) of the battery management system and configured to acquire initial current information from the main circuit (300); a second current sensing module (102) connected in series in a control circuit (200) of the battery management system and configured to acquire secondary current information from the control circuit (200); a calculation module (103) connected to both the first current sensing module (101) and the second current sensing module (102), respectively, and configured to calculate a SOC value of the battery management system based on the initial and secondary current information.
  2. SOC detection circuit of a battery management system according to Claim 1 , wherein the main circuit (300) comprises: a first interface (301), a charge/discharge control module (302) and a battery (303) electrically connected in series; wherein the first interface (301) is configured to be connected to a load or a charge source, wherein the first current sensing module (101) is connected between the first interface (301) and the battery (303) and is configured to sensing the current flowing through the load in the main circuit (300).
  3. SOC detection circuit of a battery management system according to Claim 2 , wherein the first current sensing module (101) comprises a first sampling resistor (1011); wherein a first end of the first sampling resistor (1011) is connected to the first interface (301) and a first sampling terminal (1031) of the computation module (103), and a second end of the first sampling resistor (1011) is connected to a second terminal of the battery (303) and a second sampling terminal (1032) of the computation module (103).
  4. SOC detection circuit of a battery management system according to one of the Claims 1 until 3 , wherein the control circuit (200) is connected to the battery (303) of the main circuit (300), wherein the battery (303) is configured to supply power to the control circuit (200); wherein the second current sensing module (102) is connected between an earth terminal of the control circuit (200) and a second terminal of the battery (303) and is configured to detect the self-consumption of the control circuit (200).
  5. SOC detection circuit of a battery management system according to Claim 4 , wherein the second current sensing module (102) comprises a second sampling resistor (1021); wherein a first end of the second sampling resistor (1021) is connected to a second terminal of the battery (303) and a third sampling terminal (1033) of the computation module (103), and a second end of the second sampling resistor (1021) is connected to a fourth sampling terminal (1034) of the computation module (103) and a ground terminal.
  6. SOC detection circuit of a battery management system according to one of the Claims 1 until 5 , wherein the calculation module (103) comprises: an analog-to-digital conversion unit (1035) which is connected to the first current sensing module (101) and the second current sensing module (102) respectively and is configured to convert the first current information and the second current information into digital signals; a signal processing unit (1036) which is connected to the analog-to-digital conversion unit (1035) and is configured to calculate the SOC value of the battery management system based on the first and second current information converted into digital signals.
  7. A charge/discharge control circuit comprising: a processing module (103) configured to generate a first control signal and a second control signal in response to an operating instruction from a target user; a charge control module (105) connected to the processing module (103) and configured to generate a charge voltage control signal in response to the first control signal; a discharge control module (106) connected to the processing module (103) and configured to generate a discharge voltage control signal in response to the second control signal; wherein the charge voltage control is configured to switch a charge switching transistor (M1) on or off, and the discharge voltage control is configured to switch a discharge switching transistor (M2) on or off.
  8. Charging/discharging control circuit according to Claim 7 , wherein the loading control module (105) comprises: a first tracking unit (1051) connected to the computation module (103) and configured to receive the first control signal a first drive unit (1052) connected to the first tracking unit (1051) and configured to switch on and output a first supply signal based on the first control signal; a first switching unit (1053) connected to the first drive unit (1052) and configured to switch on and output based on the first supply signal; a first output unit (1054) connected to the first switching unit (1053) and configured to output the charging voltage control.
  9. Charging/discharging control circuit according to Claim 8 , wherein the first drive unit (1052) comprises a first switching transistor (Q1), a second switching transistor (Q2), a first resistor (R1), a second resistor (R2), a third resistor (R3), and a fourth resistor (R4); wherein a first end of the first resistor (R1) is connected to the output of the first tracking unit (1051), and the second end of the first resistor (R1) is connected to the control terminal of the first switching transistor (Q1); wherein a first electrode of the first switching transistor (Q1) is connected to the control terminal of the second switching transistor (Q2), and a second electrode of the first switching transistor (Q1) is grounded; wherein a first electrode of the second switching transistor (Q2) is connected to a first supply voltage input, and the second electrode of the second switching transistor (Q2) is connected to the control terminal of the first switching unit (1053); wherein the second resistor (R2) is located between the control terminal and the second electrode of the first switching transistor (Q1), the third resistor (R3) is located between the first electrode of the first switching transistor (Q1) and the control terminal of the second switching transistor (Q2), and the fourth resistor (R4) is located between the control terminal and the first electrode of the second switching transistor (Q2).
  10. Charging/discharging control circuit according to Claim 8 , wherein the first switching unit (1053) comprises a third switching transistor (Q3) and a fifth resistor (R5); wherein the control terminal of the third switching transistor (Q3) is connected to the output of the first drive unit (1052), a first electrode of the third switching transistor (Q3) is connected to a first terminal of the first output unit (1054), and a second electrode of the third switching transistor (Q3) is grounded; wherein the fifth resistor (R5) is connected between the control terminal and the second electrode of the third switching transistor (Q3).
  11. Charging/discharging control circuit according to Claim 10 , wherein the first output unit (1054) comprises a first voltage divider network, wherein a first end of the first voltage divider network is connected to the first electrode of the third switching transistor (Q3), a second end of the first voltage divider network is configured to be connected to a second supply voltage input, and a third end of the first voltage divider network is configured to be connected to the control terminal of the charging switching transistor (M1).
  12. Charging/discharging control circuit according to one of the Claims 7 until 11 , wherein the discharge control module (106) comprises: a second tracking unit (1061) connected to the computation module (103) and configured to receive and output the second control signal; a second drive unit (1062) connected to the second tracking unit (1061) and configured to switch on and output a first supply signal based on the second control signal; a second switching unit (1063) connected to the second drive unit (1062) and configured to switch on and output based on the first supply signal; a second output unit (1064) connected to the second switching unit (1063) and configured to output the discharge voltage control.
  13. Charging/discharging control circuit according to Claim 12 , wherein the second drive unit (1062) comprises a fourth switching transistor (Q4), a fifth switching transistor (Q5), a sixth resistor (R6), a seventh resistor (R7), an eighth resistor (R8), and a ninth resistor (R9); wherein a first end of the sixth resistor (R6) is connected to the output of the second tracking unit (1061) and the second end of the sixth resistor (R6) is connected to the control terminal of the fourth switching transistor (Q4); wherein a first electrode of the fourth switching transistor (Q4) is connected to the control terminal of the fifth switching transistor (Q5) and a second electrode of the fourth switching transistor (Q4) is grounded; wherein a first electrode of the fifth switching transistor (Q5) is configured to be connected to a first supply voltage input, and a second electrode of the fifth switching transistor (Q5) is connected to the control terminal of the second switching unit (1063); wherein the seventh resistor (R7) is connected between the control terminal and the second electrode of the fourth switching transistor (Q4), which eighth resistor (R8) between the first electrode of the fourth switching transistor (Q4) and the control terminal of the fifth switching transistor (Q5); and the ninth resistor (R9) between the control terminal and the first electrode of the fifth switching transistor (Q5).
  14. Charging/discharging control circuit according to Claim 12 , wherein the second switching unit (1063) comprises a sixth switching transistor (Q6) and a tenth resistor (R10); wherein the control terminal of the sixth switching transistor (Q6) is connected to the output of the second drive unit (1062), a first electrode of the sixth switching transistor (Q6) is connected to a first terminal of the second output unit (1064), and a second electrode of the sixth switching transistor (Q6) is grounded; wherein the tenth resistor (R10) is connected between the control terminal and the second electrode of the sixth switching transistor (Q6).
  15. Charging/discharging control circuit according to Claim 14 , wherein the second output unit (1064) comprises a second voltage divider network, wherein a first end of the second voltage divider network is connected to the first electrode of the sixth switching transistor (Q6), a second end of the second voltage divider network is configured to be connected to a second supply voltage input, and a third end of the second voltage divider network is configured to be connected to the control terminal of the discharge switching transistor (M2).
  16. Charging/discharging control circuit according to one of the Claims 7 until 15 , wherein the charge/discharge control circuit further comprises an initialization module (107); wherein an input of the initialization module (107) is connected to a first supply voltage input, and an output of the initialization module (107) is connected to the charge control module (105) and the discharge control module (106); wherein the initialization module (107) is configured to initialize the charge control module (105) and the discharge control module (106) during an initialization phase, and to turn off the charge switching transistor (M1) and the discharge switching transistor (M2).
  17. Charging/discharging control circuit according to Claim 16 , wherein the initialization module (107) comprises a first capacitor (C1), an eleventh resistor (R11) and a twelfth resistor (R12); wherein a first end of the first capacitor (C1) is connected to the first supply voltage input, and a second end of the first capacitor (C1) is connected to a first end of the eleventh resistor (R11) and a first end of the twelfth resistor (R12); wherein the second end of the eleventh resistor (R11) is grounded, and the second end of the twelfth resistor (R12) is connected to the reset terminal of the first tracking unit (1051) of the charge control module (105) and to the reset terminal of the second tracking unit (1061) of the discharge control module (106).
  18. A boost control circuit comprising: a processing module (103) configured to generate a first control signal and a second control signal in response to an operating instruction from a target user; a drive module (108) connected to the processing module (103) and a first power supply input, configured to generate a switching control signal and a first voltage driver signal in response to the first and second control signals; a switching module (109) connected to a second power supply input and the drive module (108), configured to switch on or off in response to the switching control signal; a boost converter module (110) connected to the switching module (109) and the drive module (108), configured to receive a second supply signal from the second power supply input when the switching module (109) is switched on, and to perform a boost conversion based on the second supply signal and the first voltage driver signal, and to output a second voltage signal; where the magnitude of the second voltage signal is greater than the magnitude of the second supply signal.
  19. Upward control circuit after Claim 18 , wherein the drive module (108) comprises: an input logic module (1081) connected to the computation module (103) and configured to generate a first logic control signal based on the first control signal and the second control signal; a first drive module (1082) connected to the input logic module (1081) and the switching module (109) and configured to switch on and off based on the first logic control signal and output a switching control signal to the switching module (109); a second drive module (1083) connected to the input logic module (1081) and the first power supply input and configured to output a first drive signal based on the first logic control signal and the first supply signal output by the first power supply input; an output logic module (1084) connected to the two ten drive module (1083) is connected and is configured to generate the first voltage driver signal based on the first drive signal.
  20. Upward control circuit after Claim 19 , wherein the first drive module (1082) comprises a seventh switching transistor (Q7), an eighth switching transistor (Q8) and a thirteenth resistor (R13); wherein the control terminal of the seventh switching transistor (Q7) is connected to the output of the input logic module (1081), a first electrode of the seventh switching transistor (Q7) is connected to the control terminal of the eighth switching transistor (Q8) and to a first end of the thirteenth resistor (R13), a second end of the thirteenth resistor (R13) is arranged to be connected to the first power supply input, a first electrode of the eighth switching transistor (Q8) is connected to the control terminal of the switching module (109), and a second electrode of the seventh switching transistor (Q7) and a second electrode of the eighth switching transistor (Q8) are grounded.

Description

The application claims the priority right of the Chinese patent applications filed with the Chinese Patent Office on August 25, 2023, with the application numbers 202322305685.8, 202322305751.1, 202311084408.7, 202322305827.0 and 202311087750.2 , the entire content of which is incorporated into this application by reference. Technical field The present application relates to the field of battery technology and in particular to a circuit, a battery management system and an electric vehicle. State of the art The term SOC (State of Charge) refers to the remaining capacity of a battery, and the accuracy of the measurement is a crucial indicator for a battery management system. SOC measurement in a battery management system is typically performed using the ampere-hour integration method, which calculates the accumulated electrical charge. This method is widely used for both traction batteries and energy storage batteries. Technical problem In relevant technologies, such as 12V low-voltage lithium battery systems, the ampere-hour integration method for determining the state of charge (SOC) only records the external current entering and leaving the battery, without considering changes in the internal state of the battery management system. However, since the electronic components within the battery management system also draw energy directly from the battery, albeit in very small currents, the discharge accumulated over long periods can affect the accuracy of the battery management system's SOC measurement. Disclosure of registration In a first aspect, the present application provides a SOC detection circuit for a battery management system, comprising: a first current sensing module connected in series in a main circuit of the battery management system and configured to acquire initial current information from the main circuit; a second current sensing module connected in series in a control circuit of the battery management system and configured to acquire second current information from the control circuit; a calculation module that is connected to the first current sensing module and the second current sensing module and is configured to calculate the SOC value of the battery management system based on the first and second current information. In a second aspect, the present application also provides a charging/discharging control circuit, comprising: a calculation module that is configured to generate a first control signal and a second control signal in response to an operating instruction from a target user; a charging control module connected to the calculation module and configured to generate a charging voltage control in response to the first control signal; a discharge control module connected to the calculation module and configured to generate a discharge voltage control in response to the second control signal; wherein the charging voltage control is configured to switch a charging switching transistor on or off; and the discharging voltage control is configured to switch a discharging switching transistor on or off. In a third aspect, the present application also provides an upward control circuit, comprising: a calculation module that is configured to generate a first control signal and a second control signal in response to an operating instruction from a target user; a drive module connected to the calculation module and to a first power supply input, and configured to generate a switching control signal and a first voltage driver signal in response to the first and second control signals; a switching module that is connected to a second power supply input as well as to the drive module and is configured to switch on or off in response to the switching control signal; a boost converter module that is connected to the switching module and the drive module and is configured to, when switched through, The switching module receives a second supply signal from the second power supply input and performs a boost conversion based on the second supply signal and the first voltage driver signal to output a second voltage signal; where the magnitude of the second voltage signal is greater than the magnitude of the second supply signal. In a fourth aspect, the present application also provides a switching transistor detection circuit for a battery management system, wherein the battery management system comprises a battery, a charging switching module, a discharging switching module and a charging/discharging interface; wherein the charging/discharging interface is connected to the charging switching module at a first test terminal, the charging switching module is connected to the discharging switching module at a second test terminal, and the discharging switching module is connected to the battery at a third test terminal; the switching transistor detection circuit of the battery management system comprises the following: a calculation module that is set up to generate a first control signal and a second