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CN-122017571-A - Single-wire SW (switch) identification circuit for three-electric system

CN122017571ACN 122017571 ACN122017571 ACN 122017571ACN-122017571-A

Abstract

The invention relates to the technical field of lithium ion batteries, in particular to a single-wire SW identification circuit for a three-electric system. A single-wire SW identification circuit for a three-electric system comprises an isolated power supply circuit and a high-level signal detection circuit and a low-level signal detection circuit. Compared with the prior art, the single-wire SW identification circuit for the three-electric system can identify high potential and low potential, can accurately distinguish and identify on hardware even after the battery pack is protected, is simple in circuit, simple in logic, strong in compatibility, stable and reliable, and is suitable for all LEV BMS three-electric systems.

Inventors

  • WANG LIANBO

Assignees

  • 上海派智能源股份有限公司

Dates

Publication Date
20260512
Application Date
20260330

Claims (6)

  1. 1. A single-wire SW identification circuit for a three-electric system comprises an isolated power supply circuit, a high-level signal detection circuit and a low-level signal detection circuit, and is characterized in that: The isolation power supply circuit comprises an isolation power supply module (U23), a power tube, a resistor and a capacitor, wherein one end of a first resistor (R307) is respectively connected with one end of a second resistor (R312) and the gate electrode of a first power tube (Q71), the other end of the second resistor (R312) is connected with the source electrode of the first power tube (Q71) in a grounding way, the drain electrode of the first power tube (Q71) is respectively connected with the gate electrode of a second power tube (Q50) and one end of a third resistor (R273), the other end of the third resistor (R273) and the drain electrode of the second power tube (Q50) are combined and connected with 12V voltage, the source electrode of the second resistor (Q50) is respectively connected with one end of a first capacitor (C122) and the No. 2 port of the isolation power supply module (U23), the other end of the first capacitor (C122) and the No. 1 port of the isolation power supply module (U23) are grounded, the No. 4 port of the isolation power supply module (U23) is respectively connected with a high-level signal detection circuit and a low-level signal detection circuit and the gate electrode of the second capacitor (C121), the other end of the second capacitor (C121) is connected with the fourth port of the isolation power supply module (U23) and the other end of the fourth capacitor (C170) is grounded, and the other end of the isolation power module (C) is connected with the fourth port of the isolation power module (C121) is grounded, and the fourth port of the fourth resistor (C23) is grounded; The high-level signal detection circuit and the low-level signal detection circuit comprise a photoelectric coupler, a diode, a voltage stabilizing diode, a resistor and a triode, wherein a number 4 port of an isolation power supply module (U23) is respectively connected with one end of a fifth resistor (R96) and one end of a sixth resistor (R226), the other end of the fifth resistor (R96) is respectively connected with one end of a third capacitor (C93), one end of a seventh resistor (R162), one end of a first bidirectional starting diode (SD 15), the cathode of a first diode (D21), a number 1 port of a first photoelectric coupler (U9), the other end of a third capacitor (C93), the other end of a seventh resistor (R162), the other end of the first bidirectional starting diode (SD 15), the anode of a first diode (D21), the number 2 port of the first photoelectric coupler (U9) is combined and connected with the anode of a second diode (D50), the number 3 port of the first photoelectric coupler (U9) is grounded, the number 4 port of the first photoelectric coupler (U9) is connected with the fourth port of the eighth resistor (D21), and the other end of the fourth resistor (R162) is connected with the fourth resistor (D35), the other end of the fourth resistor (D15) is connected with the fourth resistor (D35), and the other end of the fourth resistor (D23) is connected with the fourth resistor (D35) of the fourth resistor (D9), and the fourth resistor (D9) is connected with the fourth resistor (D50) to the fourth resistor (D50), and the fourth resistor (D9) is connected with the fourth resistor (D9) respectively, and the fourth resistor is connected with the fourth port, the other end of the second bidirectional starting diode (SD 16), the anode of the third diode (D53) and the port No. 2 of the second photoelectric coupler (U21) are combined and connected with the anode of the fourth diode (D56), the port No. 3 of the second photoelectric coupler (U21) is grounded, the port No. 4 of the second photoelectric coupler (U21) is connected with one end of a tenth resistor (R180), the other end of the tenth resistor (R180) is connected with 3.3V voltage, the cathode of the fourth diode (D56) is connected with the collector of a triode (Q69), the base of the triode (Q69) is respectively connected with one end of an eleventh resistor (R291), one end of a twelfth resistor (R285), one end of a thirteenth resistor (R309), the other end of the eleventh resistor (R291) and the emitter of the triode (Q69) are combined and grounded, the other end of the twelfth resistor (R309) is combined and connected with one end of a fourteenth resistor (R180), the other end of the fifteenth resistor (R308) is connected with the collector of the fifteenth resistor (R69), the base of the triode (Q69) is connected with the anode of the fifth resistor (ZD) is connected with the cathode of the fifth resistor (ZD), and the base of the cathode of the fourth resistor (ZD) is connected with the anode of the fifth resistor (ZD) is connected with the cathode of the fourth resistor (ZD) is connected with the anode of the cathode (Z16).
  2. 2. The single wire SW identification circuit for a three-wire electric system according to claim 1, wherein the isolated power module (U23) is of a type B1205S-1WR3, the first power tube (Q71) is of a type L2N7002SLT1G, and the second power tube (Q50) is of a type CJ3407.
  3. 3. A single wire SW identifying circuit for a three-wire system according to claim 1, wherein said first photo coupler (U9), second photo coupler (U21) are of the type EL3H7B, triode (Q69) is of the type MMBT5551, first diode (D21) is of the type A1N4148W, second diode (D50) is of the type 1N4007/M7, third diode (D53) is of the type 1N4148W, fourth diode (D56) and fifth diode (D59) are of the type 1N4148WS, first zener diode (ZD 16) and second zener diode (ZD 15) are of the type BZT52C24, and first bidirectional departure diode (SD 15) and second bidirectional departure diode (SD 16) are of the type WS 05-DLC.
  4. 4. The single-wire SW identifying circuit for a three-wire system according to claim 1, wherein the single-wire SW identifying circuit is arranged in a battery pack, one end of the single-wire SW identifying circuit is connected with a female socket of a discharge socket, the other end of the single-wire SW identifying circuit is connected with an MCU controller, and the female socket of the discharge socket is connected with a male head of the discharge socket.
  5. 5. The single wire SW identifying circuit for three-wire electric system of claim 1, wherein the cathode of the second diode (D50) and the anode of the fifth diode (D59) are respectively connected with the female socket of the discharge socket.
  6. 6. The single-wire SW identifying circuit for a three-electric system according to claim 1, wherein the port No. 4 of the first photoelectric coupler (U9) and the port No. 4 of the second photoelectric coupler (U21) are respectively connected with the MCU controller.

Description

Single-wire SW (switch) identification circuit for three-electric system Technical Field The invention relates to the technical field of lithium ion batteries, in particular to a single-wire SW identification circuit for a three-electric system. Background The lithium battery packs at the outlet increasingly tend to be light and portable, the three battery packs are more and more required for supplying power to the LEV system, and three batteries can improve the endurance and the driving capability. The three-electric system requires that three battery packs with consistent serial numbers can be connected together to supply power for the whole system, when the voltages are consistent, the three battery packs are output together, when the voltages are inconsistent, the battery packs with high voltages are output preferentially, and until the voltages of the three battery packs are consistent, the three battery packs are output together to supply power for the whole system. And when the battery pack is removed from the vehicle, the discharge port of the battery pack is required to have no voltage, so that the physical safety of a person is ensured. At this time, it is necessary to accurately identify the battery pack access system. The existing identification circuit usually uses high potential as an identification signal if the BMS system is controlled to be negative, and uses low potential as an identification signal if the BMS system is controlled to be positive. Although other conventional circuits can identify three electricity, the B-type ground is used as a reference, the sequence of the battery pack access, voltage, electric quantity and the like can influence the circuit, so that the circuit is complex, and the problem that the battery pack cannot be detected or is detected by mistake can occur after the battery pack is protected. Disclosure of Invention The invention provides a single-wire SW identification circuit for a three-electric system, which can identify high potential and low potential, can accurately distinguish and identify on hardware even after battery pack protection, has simple circuit, simple logic and strong compatibility, is stable and reliable, and is suitable for all LEV BMS three-electric systems. In order to achieve the purpose, the single-wire SW identification circuit for the three-electric system is designed to comprise an isolated power supply circuit, a high-level signal detection circuit and a low-level signal detection circuit and is characterized in that: The isolation power supply circuit comprises an isolation power supply module, a power tube, a resistor and a capacitor, wherein one end of the first resistor is respectively connected with one end of the second resistor and the gate electrode of the first power tube, the other end of the second resistor is connected with the source electrode of the first power tube and grounded, the drain electrode of the first power tube is respectively connected with the gate electrode of the second power tube and one end of the third resistor, the other end of the third resistor and the drain electrode of the second power tube are combined and connected with 12V voltage, the source electrode of the second power tube is respectively connected with one end of the first capacitor and the No. 2 port of the isolation power supply module, the other end of the first capacitor and the No. 1 port of the isolation power supply module are grounded, the No.4 port of the isolation power supply module is respectively connected with one end of the high-low level signal detection circuit and the second capacitor, the other end of the second capacitor, the No. 3 port of the isolation power supply module and one end of the fourth resistor are connected with and grounded, and the other end of the fourth resistor is grounded; The high-low level signal detection circuit comprises a photoelectric coupler, a diode, a voltage stabilizing diode, a resistor and a triode, wherein a No. 4 port of an isolation power supply module is respectively connected with one end of a fifth resistor and one end of a sixth resistor, the other end of the fifth resistor is respectively connected with one end of a third capacitor, one end of a seventh resistor, one end of a first bidirectional starting diode, a cathode of a first diode, a No. 1 port of a first photoelectric coupler, the other end of the third capacitor, the other end of the seventh resistor, the other end of the first bidirectional starting diode, the anode of the first diode, a No. 2 port of the first photoelectric coupler are connected with the anode of the second diode in a merging mode, a No. 3 port of the first photoelectric coupler is grounded, a No. 4 port of the first photoelectric coupler is connected with one end of an eighth resistor, the other end of the eighth resistor is connected with 3.3V voltage, the other end of the sixth resistor is respectively connected with one end of a fourth capacitor,