Interlocking circuit and battery management system
By incorporating a voltage regulator circuit into the high-voltage connector circuitry to provide a fixed voltage value, the problem of inaccurate high-voltage connector detection is solved, thereby improving the safety and detection accuracy of the high-voltage system.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SUNWODA MOBILITY ENERGY TECHNOLOGY CO LTD
- Filing Date
- 2025-05-06
- Publication Date
- 2026-05-12
AI Technical Summary
In the prior art, voltage detection of high-voltage connectors is inaccurate due to voltage fluctuations, which reduces the safety and detection accuracy of high-voltage systems.
By setting a voltage regulator sub-circuit between the first power supply terminal and the interlock terminal of the high-voltage connector, a fixed voltage value is provided to prevent the voltage at both ends of the high-voltage connector from being affected by power supply fluctuations. The voltage regulator sub-circuit, composed of a voltage regulator and a resistor, combined with the acquisition sub-circuit and the switching sub-circuit, enables accurate detection of the high-voltage connector.
It improves the accuracy and circuit safety of high-voltage connector testing, reduces the false positive rate, enhances anti-disturbance capability, reduces software diagnostic errors, and improves testing accuracy and response speed.
Smart Images
Figure CN224233358U_ABST
Abstract
Description
Technical Field
[0001] This application relates to the field of high-voltage power supply technology, and in particular to an interlocking circuit and a battery management system. Background Technology
[0002] With the rapid development of new energy vehicles, batteries, as core components, directly affect a vehicle's range, safety, and lifespan. The Battery Management System (BMS) is responsible for monitoring and managing the battery status. To ensure efficient and safe battery operation, it's necessary to monitor in real time whether the high-voltage connectors in the battery pack are fault-free and properly connected to the high-voltage power supply circuit. Currently, a common high-voltage interlock detection scheme involves detecting the voltage across the high-voltage connector to determine its connection. However, because the voltage signal fluctuates with the input voltage value to the BMS, a wide voltage range is set. If the voltage across the high-voltage connector falls within this range, it's considered properly connected. This large voltage range leads to a high error rate, reducing the safety of the high-voltage system. Utility Model Content
[0003] In view of this, the purpose of this application is to provide an interlock circuit and a battery management system, which can provide a fixed voltage value to the interlock terminal by setting a voltage regulator sub-circuit between the first power supply terminal and the interlock terminal for connecting the high-voltage connector, thereby preventing the voltage at both ends of the high-voltage connector from being affected by power supply fluctuations. This solves the technical problem of inaccurate detection of the high-voltage connector caused by voltage fluctuations in the prior art, and achieves the technical effect of improving detection accuracy and circuit safety.
[0004] In a first aspect, embodiments of this application provide an interlock circuit, the interlock circuit comprising: a first power supply terminal for connecting to a power supply; a first interlock terminal connected to the first power supply terminal and for connecting to a first end of a high-voltage connector; a second interlock terminal for connecting to a second end of the high-voltage connector; and a voltage regulator sub-circuit, wherein a first connection terminal of the voltage regulator sub-circuit is connected between the first power supply terminal and the first interlock terminal, a second connection terminal of the voltage regulator sub-circuit is connected to a ground point, and a voltage regulator terminal of the voltage regulator sub-circuit is connected to the second interlock terminal to provide a fixed voltage value.
[0005] Optionally, the voltage regulator sub-circuit includes a voltage regulator, a first resistor, and a second resistor, wherein the cathode of the voltage regulator serves as the first connection terminal of the voltage regulator sub-circuit, the anode of the voltage regulator serves as the second connection terminal of the voltage regulator sub-circuit, the reference terminal of the voltage regulator is connected to the first terminal of the first resistor, the second terminal of the first resistor serves as the voltage regulator terminal of the voltage regulator sub-circuit, the first terminal of the second resistor is connected to the reference terminal of the voltage regulator, and the second terminal of the second resistor is connected to a ground point.
[0006] Optionally, the interlock circuit further includes: a first interlock acquisition sub-circuit, wherein a first end of the first interlock acquisition sub-circuit is connected between a first connection terminal of the voltage regulator sub-circuit and the first interlock terminal, and a second end of the first interlock acquisition sub-circuit serves as a first acquisition terminal for connection to the microprocessor unit; and / or, a second interlock acquisition sub-circuit, wherein a first end of the second interlock acquisition sub-circuit is connected between the voltage regulator terminal of the voltage regulator sub-circuit and the second interlock terminal, and a second end of the second interlock acquisition sub-circuit serves as a second acquisition terminal for connection to the microprocessor unit.
[0007] Optionally, the first interlocked acquisition sub-circuit includes a third resistor and a fourth resistor, wherein the first end of the third resistor serves as the first terminal of the first interlocked acquisition sub-circuit, the second end of the third resistor is connected to the first end of the fourth resistor, the second end of the fourth resistor is connected to a ground point, and the area between the third resistor and the fourth resistor serves as the first acquisition terminal; and / or, the second interlocked acquisition sub-circuit includes a fifth resistor and a sixth resistor, wherein the first end of the fifth resistor serves as the first terminal of the second interlocked acquisition sub-circuit, the second end of the fifth resistor is connected to the first end of the sixth resistor, the second end of the sixth resistor is connected to a ground point, and the area between the fifth resistor and the sixth resistor serves as the second acquisition terminal.
[0008] Optionally, the interlock circuit further includes a switching sub-circuit, wherein a first connection terminal of the switching sub-circuit is connected to the first power supply terminal, and a second connection terminal of the switching sub-circuit is connected to the first connection terminal of the voltage regulator sub-circuit. The on / off state of the switching sub-circuit is changed to change whether the first power supply terminal supplies power to the voltage regulator sub-circuit.
[0009] Optionally, the switching sub-circuit includes a current limiting unit and an isolation unit, wherein the first connection terminal of the current limiting unit serves as the first connection terminal of the switching sub-circuit, the second connection terminal of the current limiting unit serves as the second connection terminal of the switching sub-circuit, the control terminal of the current limiting unit is connected to the first connection terminal of the isolation unit, the second connection terminal of the isolation unit is connected to a ground point, and the control terminal of the isolation unit serves as the control terminal of the switching sub-circuit for connection to the microprocessor unit.
[0010] Optionally, the current limiting unit includes a seventh resistor, an eighth resistor, a ninth resistor, and a first control switch, wherein the first end of the seventh resistor serves as the first connection terminal of the current limiting unit, the second end of the seventh resistor is connected to the first connection terminal of the first control switch, the second connection terminal of the first control switch serves as the second connection terminal of the current limiting unit, the control terminal of the first control switch is connected to the first end of the eighth resistor, the second end of the eighth resistor is connected to the second end of the seventh resistor, the first end of the ninth resistor is connected to the control terminal of the first control switch, and the second end of the ninth resistor serves as the control terminal of the current limiting unit; and / or, the isolation unit includes a tenth resistor, an eleventh resistor, and a second control switch, wherein the first connection terminal of the second control switch serves as the first connection terminal of the isolation unit, the second connection terminal of the second control switch serves as the second connection terminal of the isolation unit, the control terminal of the second control switch is connected to the first end of the tenth resistor, the second end of the tenth resistor serves as the control terminal of the isolation unit, the first end of the eleventh resistor is connected to the control terminal of the second control switch, and the second end of the eleventh resistor is connected to a ground point.
[0011] Optionally, the circuit further includes a fault detection sub-circuit, the first end of which is connected to a pull-up power supply, and the second end of which is connected between the voltage regulator terminal of the voltage regulator sub-circuit and the second interlock terminal. The voltage value of the second interlock terminal is limited to be different from the voltage value of the power supply by setting the voltage value of the pull-up power supply and the specifications of the electronic components in the fault detection sub-circuit.
[0012] Optionally, the fault detection sub-circuit includes a twelfth resistor and a reverse protection diode, wherein the anode of the reverse protection diode serves as the first terminal of the fault detection sub-circuit, the cathode of the reverse protection diode is connected to the first terminal of the twelfth resistor, and the second terminal of the twelfth resistor serves as the second terminal of the fault detection sub-circuit.
[0013] Secondly, embodiments of this application also provide a battery management system, the battery management system comprising: a microprocessor unit, a first acquisition pin of the microprocessor unit for connecting to the first interlock terminal, and a second acquisition pin of the microprocessor unit for connecting to the second interlock terminal; an interlock circuit as described in the first aspect or any possible implementation of the first aspect; wherein the power supply is the input power supply of the battery management system.
[0014] This application provides an interlock circuit and battery management system. The interlock circuit includes: a first power supply terminal for connecting to a power supply; a first interlock terminal connected to the first power supply terminal and used to connect to a first end of a high-voltage connector; a second interlock terminal for connecting to a second end of the high-voltage connector; and a voltage regulator sub-circuit, wherein a first connection terminal of the voltage regulator sub-circuit is connected between the first power supply terminal and the first interlock terminal, a second connection terminal of the voltage regulator sub-circuit is connected to a ground point, and a voltage regulator terminal of the voltage regulator sub-circuit is connected to the second interlock terminal to provide a fixed voltage value. By placing the voltage regulator sub-circuit between the first power supply terminal and the interlock terminal for connecting the high-voltage connector, a fixed voltage value can be provided to the interlock terminal through the voltage regulator sub-circuit, preventing the voltage across the high-voltage connector from being affected by power supply fluctuations. This solves the technical problem of inaccurate high-voltage connector detection caused by voltage fluctuations in the prior art, and achieves the technical effect of improving detection accuracy and circuit safety.
[0015] To make the above-mentioned objectives, features and advantages of this application more apparent and understandable, preferred embodiments are described below in detail with reference to the accompanying drawings. Attached Figure Description
[0016] To more clearly illustrate the technical solutions of the embodiments of this application, the accompanying drawings used in the embodiments will be briefly introduced below. It should be understood that the following drawings only show some embodiments of this application and should not be regarded as a limitation of the scope. For those skilled in the art, other related drawings can be obtained based on these drawings without creative effort.
[0017] Figure 1 A schematic diagram of an interlock circuit provided in an embodiment of this application is shown.
[0018] Figure 2 A circuit diagram of an interlock circuit provided in an embodiment of this application is shown.
[0019] Explanation of key component symbols:
[0020] In the diagram: First power supply terminal V1; First interlock terminal K1; High-voltage connector S1; Second interlock terminal K2; Voltage regulator sub-circuit 101; Grounding point GND; Voltage regulator U1; First resistor R1; Second resistor R2; First interlock acquisition sub-circuit 102; Third resistor R3; Fourth resistor R4; First acquisition terminal Y1; Second interlock acquisition sub-circuit 103; Fifth resistor R5; Sixth resistor R6; Second acquisition terminal Y2; Switch sub-circuit 104; Current limiting unit 1041; Seventh resistor R7; Eighth resistor R8; Ninth resistor R9; First control switch Q1; Isolation unit 1042; Tenth resistor R10; Eleventh resistor R11; Second control switch Q2; Control terminal Y3 of switch sub-circuit 104; Fault detection sub-circuit 105; Pull-up power supply V2; Twelfth resistor R12; Anti-reverse diode D1; Freewheeling diode D2. Detailed Implementation
[0021] To make the objectives, technical solutions, and advantages of the embodiments of this application clearer, the technical solutions of the embodiments of this application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of this application, and not all embodiments. The components of the embodiments of this application described and shown in the accompanying drawings can generally be arranged and designed in various different configurations. Therefore, the following detailed description of the embodiments of this application provided in the accompanying drawings is not intended to limit the scope of the claimed application, but merely represents selected embodiments of this application. Based on the embodiments of this application, every other embodiment obtained by those skilled in the art without inventive effort falls within the scope of protection of this application.
[0022] Since the battery pack supplies power to the vehicle, it needs to provide a warning to the vehicle controller before the high-voltage circuit is de-energized, allowing the vehicle system sufficient response time to take countermeasures. High-voltage interlocking uses the detection signal from the low-voltage circuit to determine whether the high-voltage connector in the high-voltage circuit is fully and securely connected, ensuring the electrical continuity and integrity of the high-voltage circuit. Existing technology uses the level signals or pulse width modulation (PWM) pulse signals at the output and input terminals of the low-voltage interlock circuit to determine the voltage signals at both ends of the high-voltage connector, thus detecting the integrity of the high-voltage interlock circuit. Because the voltage signals corresponding to the output and input terminals of the interlock fluctuate with the supply voltage of the battery management system, setting a wide voltage range for judgment results in a high fault tolerance rate, reducing the safety of the high-voltage system. Furthermore, due to the line impedance between the high-voltage connector and the interlock circuit, a voltage drop occurs, which may cause inconsistencies in the voltage values collected when detecting the output and input terminals, leading to misjudgments and low detection accuracy. It is also susceptible to interference from other signals, which can interfere with the status of high-voltage interlock diagnosis, causing the signals detected at the output and input terminals to deviate by a large or small amount, which can easily lead to misjudgment.
[0023] To address the aforementioned problems, this application provides an interlock circuit and battery management system. By placing a voltage regulator sub-circuit between the first power supply terminal and the interlock terminal for connecting the high-voltage connector, a fixed voltage value is provided to the interlock terminal through the voltage regulator sub-circuit. This prevents the voltage across the high-voltage connector from being affected by power supply fluctuations, solving the technical problem of inaccurate high-voltage connector detection caused by voltage fluctuations in the prior art. The system achieves the technical effect of improving detection accuracy and circuit safety, as detailed below:
[0024] Please see Figure 1 , Figure 1 This is a schematic diagram of an interlocking circuit provided in an embodiment of this application. Figure 1 As shown, the interlock circuit provided in this application embodiment includes: a first power supply terminal V1 for connecting to a power supply; a first interlock terminal K1 connected to the first power supply terminal V1 and for connecting to the first end of a high-voltage connector S1; a second interlock terminal K2 for connecting to the second end of the high-voltage connector S1; and a voltage regulator sub-circuit 101, wherein the first connection terminal of the voltage regulator sub-circuit 101 is connected between the first power supply terminal V1 and the first interlock terminal K1, the second connection terminal of the voltage regulator sub-circuit 101 is connected to a ground point GND, and the voltage regulator terminal of the voltage regulator sub-circuit 101 is connected to the second interlock terminal K2 to provide a fixed voltage value.
[0025] The first interlocking end K1 and the second interlocking end K2 are used to connect the two ends of the high-voltage connector S1, which is installed on the high-voltage power supply circuit. When the high-voltage connector S1 is open, the high-voltage power supply circuit is open; when the high-voltage connector S1 is closed, the high-voltage power supply circuit is open. That is, the on / off state of the high-voltage connector S1 is used to indicate whether high-voltage power supply is being provided.
[0026] Furthermore, the connection status of the high-voltage connector S1 can be determined by collecting the voltage values of the first interlock terminal K1 and the second interlock terminal K2. When the high-voltage connector S1 is closed, the voltage values of the first interlock terminal K1 and the second interlock terminal K2 are equal, and this is a fixed voltage value provided by the voltage regulator circuit 101. This prevents voltage fluctuations at the first power supply terminal V1 from affecting the voltage values of the first interlock terminal K1 and the second interlock terminal K2. Therefore, providing a fixed voltage value increases the circuit's anti-disturbance capability, improves detection accuracy, and prevents misjudgments.
[0027] Please see Figure 2 , Figure 2 This is a circuit diagram of an interlocking circuit provided in an embodiment of this application. Figure 2 As shown, the voltage regulator sub-circuit 101 includes a voltage regulator U1, a first resistor R1, and a second resistor R2. The cathode of the voltage regulator U1 serves as the first connection terminal of the voltage regulator sub-circuit 101, and the anode of the voltage regulator U1 serves as the second connection terminal of the voltage regulator sub-circuit 101. The reference terminal of the voltage regulator U1 is connected to the first terminal of the first resistor R1, and the second terminal of the first resistor R1 serves as the voltage regulator terminal of the voltage regulator sub-circuit 101. The first terminal of the second resistor R2 is connected to the reference terminal of the voltage regulator U1, and the second terminal of the second resistor R2 is connected to the ground point GND.
[0028] In other words, when the high-voltage connector S1 is closed, the electrical energy received by the first power supply terminal V1 is transmitted sequentially to the voltage regulator circuit 101 through the first interlock terminal K1, the high-voltage connector S1, and the second interlock terminal K2. The voltage regulator U1 of the voltage regulator circuit 101 changes the conduction between the anode and cathode of the voltage regulator U1 by the voltage value collected by its reference terminal, so that the voltage value at the reference terminal of the voltage regulator U1 is maintained at the preset reference voltage of the voltage regulator U1. When the voltage value collected at the reference electrode of voltage regulator U1 is greater than the preset reference voltage, the cathode and anode of voltage regulator U1 are connected. Since the anode of voltage regulator U1 is grounded, the voltage value of the anode of voltage regulator U1 is lowered, and the voltage values of the first interlock terminal K1 and the second interlock terminal K2 are also lowered accordingly, and the voltage of the reference electrode of voltage regulator U1 is also lowered accordingly. When the voltage value collected at the reference electrode of voltage regulator U1 is less than the preset reference voltage, the cathode and anode of voltage regulator U1 are disconnected, and the voltage value of the anode of voltage regulator U1 is raised. The voltage values of the first interlock terminal K1 and the second interlock terminal K2 are also raised accordingly, and the voltage of the reference electrode of voltage regulator U1 is also raised accordingly. Thus, the reference electrode of voltage regulator U1 can be stabilized at the preset reference voltage.
[0029] Furthermore, the fixed voltage value provided at the reference terminal of the voltage regulator circuit 101 Among them, V ref This refers to the preset reference voltage of the reference terminal of the voltage regulator U1, R1 refers to the resistance value of the first resistor R1, and R2 refers to the resistance value of the second resistor R2. Therefore, by selecting the resistance values of the first resistor R1 and the second resistor R2 paired with the voltage regulator U1, the fixed voltage value of the reference terminal of the voltage regulator sub-circuit 101 can be stabilized at the desired voltage value.
[0030] Furthermore, the microcontroller unit (MCU) can determine whether the high-voltage connector S1 is closed by acquiring the voltage values corresponding to the first interlock terminal K1 and the second interlock terminal K2, respectively. If the voltage values of the first interlock terminal K1 and the second interlock terminal K2 are equal and are the fixed voltage values of the reference terminal of the voltage regulator circuit 101, the high-voltage connector S1 is considered closed. If the voltage values of the first interlock terminal K1 and the second interlock terminal K2 are not equal, and the voltage value of either interlock terminal is not at the fixed voltage value of the reference terminal of the voltage regulator circuit 101, the high-voltage connector S1 is considered open. Thus, the closure status of the high-voltage connector S1 can be detected, and even if there are voltage fluctuations in the power supply connected to the first power terminal V1, the fixed voltage value provided by the voltage regulator circuit 101 remains stable, preventing fluctuations in the voltage values of the first interlock terminal K1 and the second interlock terminal K2. This eliminates the need for a wide voltage range and improves detection accuracy.
[0031] For example, the resistance values of the first resistor R1 and the second resistor R2 are set to reduce the impedance effect caused by the high-voltage connector S1 and the wiring. The wiring includes a first line connecting the first end of the high-voltage connector S1 to the first interlocking end K1 and a second line connecting the second end of the high-voltage connector S1 to the second interlocking end K2.
[0032] In other words, a connection line needs to be set between the first end of the high-voltage connector S1 and the first interlocking end K1, and a connection line also needs to be set between the second end of the high-voltage connector S1 and the second interlocking end K2. When the connection line is too long, there will be impedance, which may cause the voltage values corresponding to the first interlocking end K1 and the second interlocking end K2 to be different, affecting the accuracy of detection. Since the voltage regulator circuit 101 of this application is equipped with a first resistor R1 and a second resistor R2, and the resistance values of the first resistor R1 and the second resistor R2 are set to the kiloohm level, the existence of the first resistor R1 and the second resistor R2 can ignore the line impedance between the high-voltage connector S1 and the interlocking end, thereby preventing the voltage values of the first interlocking end K1 and the second interlocking end K2 from being different due to line impedance.
[0033] like Figure 2 As shown, the interlock circuit further includes: a first interlock acquisition sub-circuit 102, the first end of which is connected between the first connection terminal of the voltage regulator sub-circuit 101 and the first interlock terminal K1, and the second end of which serves as the first acquisition terminal Y1 for connection to the microprocessor unit; and / or, a second interlock acquisition sub-circuit 103, the first end of which is connected between the voltage regulator terminal of the voltage regulator sub-circuit 101 and the second interlock terminal K2, and the second end of which serves as the second acquisition terminal Y2 for connection to the microprocessor unit.
[0034] In other words, the microprocessor unit does not directly collect the voltage values of the first interlock terminal K1 and the second interlock terminal K2. Instead, the microprocessor unit collects the voltage value of the second terminal of the first interlock acquisition sub-circuit 102 through the first acquisition terminal Y1 and calculates the voltage value of the first interlock terminal K1 based on it. It also collects the voltage value of the second terminal of the second interlock acquisition sub-circuit 103 through the second acquisition terminal Y2 and calculates the voltage value of the second interlock terminal K2 based on it. This prevents the microprocessor unit from directly connecting to the first interlock terminal K1 and the second interlock terminal K2, thus avoiding excessive voltage values at the interlock terminals that could burn out the microprocessor unit.
[0035] For example, the first interlocked acquisition sub-circuit 102 includes a third resistor R3 and a fourth resistor R4, wherein the first end of the third resistor R3 serves as the first end of the first interlocked acquisition sub-circuit 102, the second end of the third resistor R3 is connected to the first end of the fourth resistor R4, the second end of the fourth resistor R4 is connected to the ground point GND, and the area between the third resistor R3 and the fourth resistor R4 serves as the first acquisition terminal Y1.
[0036] For example, the second interlocked acquisition sub-circuit 103 includes a fifth resistor R5 and a sixth resistor R6, wherein the first end of the fifth resistor R5 serves as the first end of the second interlocked acquisition sub-circuit 103, the second end of the fifth resistor R5 is connected to the first end of the sixth resistor R6, the second end of the sixth resistor R6 is connected to the ground point GND, and the area between the fifth resistor R5 and the sixth resistor R6 serves as the second acquisition terminal Y2.
[0037] In other words, the voltage value of the first interlock terminal K1 Among them, V Y1 This refers to the voltage value at the first acquisition terminal Y1, R3 refers to the resistance value of the third resistor R3, and R4 refers to the resistance value of the fourth resistor R4. The voltage value at the second interlock terminal K2... Among them, V Y2 R1 refers to the voltage value at the second acquisition terminal Y2, R5 refers to the resistance value of the fifth resistor R5, and R6 refers to the resistance value of the sixth resistor R6. Furthermore, the voltage value at the first interlock terminal K1 is reduced by dividing the voltage between the third resistor R3 and the fourth resistor R4, and the voltage value at the second interlock terminal K2 is reduced by dividing the voltage between the fifth resistor R5 and the sixth resistor R6, preventing high voltage from burning out the microprocessor unit.
[0038] like Figure 2 As shown, the interlock circuit also includes a switch sub-circuit 104, wherein the first connection terminal of the switch sub-circuit 104 is connected to the first power supply terminal V1, and the second connection terminal of the switch sub-circuit 104 is connected to the first connection terminal of the voltage regulator sub-circuit 101. By changing the on / off state of the switch sub-circuit 104, the first power supply terminal V1 supplies power to the voltage regulator sub-circuit 101.
[0039] In other words, when the switching sub-circuit 104 is in the on state, the power supply connected to the first power supply terminal V1 supplies power to the voltage regulator sub-circuit 101; when the switching sub-circuit 104 is in the off state, the power supply connected to the first power supply terminal V1 does not supply power to the voltage regulator sub-circuit 101.
[0040] Specifically, the switching sub-circuit 104 includes a current limiting unit 1041 and an isolation unit 1042. The first connection terminal of the current limiting unit 1041 serves as the first connection terminal of the switching sub-circuit 104, and the second connection terminal of the current limiting unit 1041 serves as the second connection terminal of the switching sub-circuit 104. The control terminal of the current limiting unit 1041 is connected to the first connection terminal of the isolation unit 1042, and the second connection terminal of the isolation unit 1042 is connected to the ground point GND. The control terminal of the isolation unit 1042 serves as the control terminal Y3 of the switching sub-circuit 104, which is used to connect to the microprocessor unit.
[0041] In other words, the current limiting unit 1041 can limit the voltage and current flowing from the first power supply terminal V1 to the first connection terminal of the voltage regulator circuit 101, so as to prevent the first connection terminal of the voltage regulator circuit 101 from receiving excessive current and voltage. The isolation unit 1042 can isolate the microprocessor unit from the first power supply terminal V1, preventing the microprocessor unit from being burned out. Furthermore, the microprocessor unit sends a control signal through the control terminal Y3 of the switching sub-circuit 104 to change the on / off state of the switching sub-circuit 104.
[0042] For example, the current limiting unit 1041 includes a seventh resistor R7, an eighth resistor R8, a ninth resistor R9, and a first control switch Q1. The first end of the seventh resistor R7 serves as the first connection terminal of the current limiting unit 1041. The second end of the seventh resistor R7 is connected to the first connection terminal of the first control switch Q1. The second connection terminal of the first control switch Q1 serves as the second connection terminal of the current limiting unit 1041. The control terminal of the first control switch Q1 is connected to the first end of the eighth resistor R8. The second end of the eighth resistor R8 is connected to the second end of the seventh resistor R7. The first end of the ninth resistor R9 is connected to the control terminal of the first control switch Q1. The second end of the ninth resistor R9 serves as the control terminal of the current limiting unit 1041.
[0043] For example, the isolation unit 1042 includes a tenth resistor R10, an eleventh resistor R11, and a second control switch Q2. The first connection terminal of the second control switch Q2 serves as the first connection terminal of the isolation unit 1042, the second connection terminal of the second control switch Q2 serves as the second connection terminal of the isolation unit 1042, the control terminal of the second control switch Q2 is connected to the first terminal of the tenth resistor R10, the second terminal of the tenth resistor R10 serves as the control terminal of the isolation unit 1042, the first terminal of the eleventh resistor R11 is connected to the control terminal of the second control switch Q2, and the second terminal of the eleventh resistor R11 is connected to the ground point GND.
[0044] In this circuit, the seventh resistor R7 limits the maximum current input to the first interlock terminal K1. The eighth resistor R8 and the ninth resistor R9 serve as the driving resistors for the first control switch Q1, which can be a PNP transistor. The tenth resistor R10 and the eleventh resistor R11 serve as the driving resistor and current-limiting resistor for the second control switch Q2, which can be an NPN transistor. When the microprocessor unit sends a high-level signal to the control terminal of the second control switch Q2, the second control switch Q2 is turned on, pulling the control terminal of the first control switch Q1 low through the second control switch Q2, thus turning on the first control switch Q1. This allows the seventh resistor R7 to perform its current-limiting function and the switch sub-circuit 104 to conduct. When the microprocessor unit sends a low-level signal to the control terminal of the second control switch Q2, the second control switch Q2 is turned off, and the control terminal of the first control switch Q1 is no longer grounded through the second control switch Q2, thus turning off the first control switch Q1 and disconnecting the switch sub-circuit 104.
[0045] Specifically, since it is necessary to continuously detect whether the high-voltage connector S1 is conducting in practical applications, the microprocessor unit will continuously send a high-level signal to the control terminal of the second control switch Q2 to control the switch sub-circuit 104 to close, so as to continuously detect the on / off state of the high-voltage connector S1.
[0046] For example, the interlock circuit also includes a freewheeling diode D2, the anode of which is connected to the first connection terminal of the voltage regulator sub-circuit 101, and the cathode of which is connected to the first terminal of the first interlock acquisition sub-circuit 102. Furthermore, the freewheeling diode D2 can smooth the current and prevent reverse voltage, improving the safety of the connection between the first power supply terminal V1 and the first connection terminal of the voltage regulator sub-circuit 101.
[0047] Therefore, when the high-voltage connector S1 is not conducting and the circuit is fault-free, the voltage value of the first interlock terminal K1 should be the voltage value of the first power supply terminal V1 minus the voltage value between the collector and emitter of the first control switch Q1, and then minus the voltage value of the freewheeling diode D2. At this time, since the high-voltage connector S1 is not conducting, the voltage regulator circuit 101 will not provide a fixed voltage value, and the voltage value of the first interlock terminal K1 is not equal to the fixed voltage value. However, the microprocessor unit can still determine the fault condition of the first interlock terminal K1 by determining the voltage value of the first interlock terminal K1.
[0048] In other words, whether the first interlock terminal K1 is short-circuited to the power supply is determined by whether the voltage value of the first interlock terminal K1 is equal to the voltage value of the power supply; whether the first interlock terminal K1 has a ground fault is determined by whether the voltage value of the first interlock terminal K1 is zero. If the voltage value of the first interlock terminal K1 is equal to the voltage value of the power supply, it is considered that the first interlock terminal K1 is short-circuited to the power supply; if the voltage value of the first interlock terminal K1 is zero, it is considered that the first interlock terminal K1 has a ground fault.
[0049] like Figure 2 As shown, the circuit also includes a fault detection sub-circuit 105. The first end of the fault detection sub-circuit 105 is connected to the pull-up power supply V2, and the second end of the fault detection sub-circuit 105 is connected between the voltage regulator terminal of the voltage regulator sub-circuit 101 and the second interlock terminal K2. The voltage value of the pull-up power supply V2 and the specifications of the electronic components in the fault detection sub-circuit 105 are set to limit the voltage value of the second interlock terminal K2 from being different from the voltage value of the power supply when the high-voltage connector S1 is not turned on.
[0050] In other words, when the high-voltage connector S1 is not conducting, fault detection is performed by collecting the voltage value of the second interlock terminal K2. At this time, since the high-voltage connector S1 is not conducting, the voltage value of the second interlock terminal K2 is not equal to the fixed voltage value, and the microprocessor unit can still determine the fault condition of the second interlock terminal K2 by determining the voltage value of the second interlock terminal K2.
[0051] Furthermore, whether the voltage value of the second interlock terminal K2 is equal to the voltage value of the power supply is used to determine if the second interlock terminal K2 is short-circuited with the power supply, and whether the voltage value of the second interlock terminal K2 is zero is used to determine if the second interlock terminal K2 has a ground fault. If the voltage value of the second interlock terminal K2 is equal to the voltage value of the power supply, it is considered that the second interlock terminal K2 is short-circuited with the power supply; if the voltage value of the second interlock terminal K2 is zero, it is considered that the second interlock terminal K2 has a ground fault. Therefore, it is necessary to set the voltage value of the pull-up power supply V2 and the specifications of the electronic components in the fault detection sub-circuit 105 to ensure that the voltage value of the second interlock terminal K2 is different from the voltage value of the power supply when the high-voltage connector S1 is not conducting, thus preventing detection errors.
[0052] For example, the fault detection sub-circuit 105 includes a twelfth resistor R12 and a reverse protection diode D1, wherein the anode of the reverse protection diode D1 serves as the first terminal of the fault detection sub-circuit 105, the cathode of the reverse protection diode D1 is connected to the first terminal of the twelfth resistor R12, and the second terminal of the twelfth resistor R12 serves as the second terminal of the fault detection sub-circuit 105.
[0053] Among them, the anti-reverse diode D1 prevents reverse voltage, and the twelfth resistor R12 is a voltage divider resistor. When the high-voltage connector S1 is not conducting, the voltage value at the second interlock terminal K2 is... Where V2 refers to the voltage value of the pull-up power supply V2, V D1 This refers to the voltage rating of the reverse protection diode D1, R5 refers to the resistance value of the fifth resistor R5, and R6 refers to the resistance value of the sixth resistor R6. 12 This refers to the resistance value of the twelfth resistor, R12. Furthermore, when the high-voltage connector S1 is not conducting, the voltage value V at the second interlock terminal K2... K2 The voltage value should be different from that of the power supply to facilitate detection of whether the second interlock terminal K2 is short-circuited with the power supply.
[0054] Furthermore, when the high-voltage connector S1 is not conducting, the voltage values of the first interlock terminal K1 and the second interlock terminal K2 can be used to analyze whether there is a short circuit fault or grounding fault in the circuit. When the high-voltage connector S1 is conducting, due to the fixed voltage value provided by the voltage regulator terminal of the voltage regulator sub-circuit 101, the voltage values of the first interlock terminal K1 and the second interlock terminal K2 can be adjusted to a fixed voltage value, allowing for continuous detection of whether the high-voltage connector S1 is closed.
[0055] Therefore, the interlocking circuit provided in this application can reduce the impact of harness impedance and external voltage fluctuations, improve the acquisition accuracy by providing a fixed voltage value, enhance the detection accuracy, response speed and reliability, narrow the set voltage range, reduce software diagnostic errors, improve the correctness of interlocking circuit fault judgment, and use simple components for construction in the circuit design process, which is low cost and has a small number of components, saving costs and printing circuit board (PCB) layout space of the interlocking circuit.
[0056] Based on the same application concept, this application also provides a battery management system corresponding to the interlock circuit provided in the above embodiments. Since the principle of the battery management system in this application is similar to that of the interlock circuit in the above embodiments, the implementation of the battery management system can refer to the implementation of the above embodiments, and the repeated parts will not be described again.
[0057] For example, this application provides a battery management system, which includes: a microprocessor unit, a first acquisition pin of the microprocessor unit for connecting to the first interlock terminal K1, and a second acquisition pin of the microprocessor unit for connecting to the second interlock terminal K2; and an interlock circuit as described in the above embodiment; wherein the power supply is the input power supply of the battery management system.
[0058] Furthermore, the microprocessor unit determines the voltage value of the first interlock terminal K1 through the first acquisition pin and the voltage value of the second interlock terminal K2 through the second acquisition pin, thereby detecting the continuity of the high-voltage connector S1. In this way, the battery management system continuously detects whether the high-voltage power supply circuit is conducting normally during the battery pack power supply process, preventing faults from occurring.
[0059] In the description of this application, it should be noted that the terms "inner" and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, or the orientation or positional relationship commonly used when the product is in use. They are used only for the convenience of describing this application and for simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application. Furthermore, the terms "first," "second," etc., are used only to distinguish descriptions and should not be construed as indicating or implying relative importance.
[0060] It should also be noted that, unless otherwise explicitly specified and limited, the terms "setup" and "connection" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection of two components. Those skilled in the art can understand the specific meaning of the above terms in this application based on the specific circumstances.
[0061] The above description is merely an embodiment of this application and is not intended to limit the scope of protection of this application. Various modifications and variations can be made to this application by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of this application should be included within the scope of protection of this application.
Claims
1. An interlocking circuit, characterized in that, The interlock circuit includes: The first power supply terminal (V1) is used to connect to the power supply. The first interlock terminal (K1) is connected to the first power supply terminal (V1) and is used to connect to the first terminal of the high-voltage connector (S1). The second interlock terminal (K2) is used to connect to the second terminal of the high-voltage connector (S1); A voltage regulator circuit (101) is provided, wherein the first connection terminal of the voltage regulator circuit (101) is connected between the first power supply terminal (V1) and the first interlock terminal (K1), the second connection terminal of the voltage regulator circuit (101) is connected to the ground point (GND), and the voltage regulator terminal of the voltage regulator circuit (101) is connected to the second interlock terminal (K2) to provide a fixed voltage value.
2. The interlocking circuit according to claim 1, characterized in that, The voltage regulator sub-circuit (101) includes a voltage regulator (U1), a first resistor (R1), and a second resistor (R2). In this circuit, the cathode of the voltage regulator (U1) serves as the first connection terminal of the voltage regulator sub-circuit (101), the anode of the voltage regulator (U1) serves as the second connection terminal of the voltage regulator sub-circuit (101), the reference terminal of the voltage regulator (U1) is connected to the first terminal of the first resistor (R1), the second terminal of the first resistor (R1) serves as the voltage regulator terminal of the voltage regulator sub-circuit (101), the first terminal of the second resistor (R2) is connected to the reference terminal of the voltage regulator (U1), and the second terminal of the second resistor (R2) is connected to the ground point (GND).
3. The interlocking circuit according to claim 1, characterized in that, The interlock circuit also includes: The first interlocked acquisition sub-circuit (102) has a first end connected between the first connection end of the voltage regulator sub-circuit (101) and the first interlock end (K1), and the second end of the first interlocked acquisition sub-circuit (102) serves as the first acquisition end (Y1) for connection to the microprocessor unit. And / or, a second interlocked acquisition sub-circuit (103), the first end of which is connected between the voltage regulator terminal of the voltage regulator sub-circuit (101) and the second interlock terminal (K2), and the second end of which serves as the second acquisition terminal (Y2) for connection to the microprocessor unit.
4. The interlocking circuit according to claim 3, characterized in that, The first interlocked acquisition sub-circuit (102) includes a third resistor (R3) and a fourth resistor (R4). Wherein, the first end of the third resistor (R3) serves as the first end of the first interlocked acquisition sub-circuit (102), the second end of the third resistor (R3) is connected to the first end of the fourth resistor (R4), the second end of the fourth resistor (R4) is connected to the ground point (GND), and the area between the third resistor (R3) and the fourth resistor (R4) serves as the first acquisition end (Y1). And / or, the second interlocked acquisition sub-circuit (103) includes a fifth resistor (R5) and a sixth resistor (R6), Wherein, the first end of the fifth resistor (R5) serves as the first end of the second interlocked acquisition sub-circuit (103), the second end of the fifth resistor (R5) is connected to the first end of the sixth resistor (R6), the second end of the sixth resistor (R6) is connected to the ground point (GND), and the area between the fifth resistor (R5) and the sixth resistor (R6) serves as the second acquisition terminal (Y2).
5. The interlocking circuit according to claim 1, characterized in that, The interlock circuit also includes a switch sub-circuit (104). The first connection terminal of the switch sub-circuit (104) is connected to the first power supply terminal (V1), and the second connection terminal of the switch sub-circuit (104) is connected to the first connection terminal of the voltage regulator sub-circuit (101). The on / off state of the switch sub-circuit (104) is changed to change whether the first power supply terminal (V1) supplies power to the voltage regulator sub-circuit (101).
6. The interlocking circuit according to claim 5, characterized in that, The switching sub-circuit (104) includes a current limiting unit (1041) and an isolation unit (1042). Wherein, the first connection terminal of the current limiting unit (1041) serves as the first connection terminal of the switching sub-circuit (104), the second connection terminal of the current limiting unit (1041) serves as the second connection terminal of the switching sub-circuit (104), the control terminal of the current limiting unit (1041) is connected to the first connection terminal of the isolation unit (1042), the second connection terminal of the isolation unit (1042) is connected to the ground point (GND), and the control terminal of the isolation unit (1042) serves as the control terminal (Y3) of the switching sub-circuit (104), which is used to connect to the microprocessor unit.
7. The interlocking circuit according to claim 6, characterized in that, The current limiting unit (1041) includes a seventh resistor (R7), an eighth resistor (R8), a ninth resistor (R9), and a first control switch (Q1). Wherein, the first end of the seventh resistor (R7) serves as the first connection end of the current limiting unit (1041), the second end of the seventh resistor (R7) is connected to the first connection end of the first control switch (Q1), the second connection end of the first control switch (Q1) serves as the second connection end of the current limiting unit (1041), the control end of the first control switch (Q1) is connected to the first end of the eighth resistor (R8), the second end of the eighth resistor (R8) is connected to the second end of the seventh resistor (R7), the first end of the ninth resistor (R9) is connected to the control end of the first control switch (Q1), and the second end of the ninth resistor (R9) serves as the control end of the current limiting unit (1041); And / or, the isolation unit (1042) includes a tenth resistor (R10), an eleventh resistor (R11), and a second control switch (Q2). Wherein, the first connection terminal of the second control switch (Q2) serves as the first connection terminal of the isolation unit (1042), the second connection terminal of the second control switch (Q2) serves as the second connection terminal of the isolation unit (1042), the control terminal of the second control switch (Q2) is connected to the first terminal of the tenth resistor (R10), the second terminal of the tenth resistor (R10) serves as the control terminal of the isolation unit (1042), the first terminal of the eleventh resistor (R11) is connected to the control terminal of the second control switch (Q2), and the second terminal of the eleventh resistor (R11) is connected to the ground point (GND).
8. The interlocking circuit according to claim 1 or 5, characterized in that, The interlock circuit further includes a fault detection sub-circuit (105), the first terminal of which is connected to the pull-up power supply (V2), and the second terminal of which is connected between the voltage regulator terminal of the voltage regulator sub-circuit (101) and the second interlock terminal (K2). Specifically, by setting the voltage value of the pull-up power supply and the specifications of the electronic components in the fault detection sub-circuit (105), the voltage value of the second interlock terminal (K2) is limited to be different from the voltage value of the power supply when the high-voltage connector (S1) is not turned on.
9. The interlocking circuit according to claim 8, characterized in that, The fault detection sub-circuit (105) includes a twelfth resistor (R12) and a reverse protection diode (D1). Wherein, the anode of the anti-reverse diode (D1) serves as the first terminal of the fault detection sub-circuit (105), the cathode of the anti-reverse diode (D1) is connected to the first terminal of the twelfth resistor (R12), and the second terminal of the twelfth resistor (R12) serves as the second terminal of the fault detection sub-circuit (105).
10. A battery management system, characterized in that, The battery management system includes: The microprocessor unit has a first acquisition pin for connecting to the first interlock terminal (K1) and a second acquisition pin for connecting to the second interlock terminal (K2). The interlocking circuit as described in any one of claims 1 to 9; in, The power supply is the input power for the battery management system.