A PDU security control system

Abstract

The application discloses a PDU safety control system and belongs to the electronic technical field.The system comprises a controller unit, a relay, a controller and a power supply, and the controller unit further comprises an MCU, an IGN control circuit, a PDU backup circuit and an MCU shutdown control circuit.The self-locking circuit is formed through the PDU backup circuit, and the PDU backup circuit is closed through the MCU shutdown control circuit to form the PDU safety control system.The technical effect of the application is that the IGN control circuit can normally output when the MCU is abnormal, and a system safety power-off method is provided, and the safety and reliability of the system are improved.

Description

Technical Field

[0001] This invention belongs to the field of electronic technology, specifically, it relates to a PDU safety control system. Background Technology

[0002] Driven by market demands for automotive safety, the safety requirements for PDU (Power Distribution Unit) control are becoming increasingly stringent. When a customer is using a vehicle, the MCU controls the IGN (Ignition Switch) output. IGN refers to the power supply system controlled by the ignition switch. If the MCU malfunctions or fails, causing it to fail, the entire vehicle's IGN will lose power, thus affecting overall PDU control and impacting customer safety. Therefore, a safer PDU control method is becoming increasingly urgent.

[0003] Prior art document (CN113685302A) discloses a method for preventing accidental triggering of the vehicle's IGN power-off. This solution sets the signal output type of the control port on the MCU main chip in the IGN power supply system, used to break the self-locking circuit, to a PWM type with adjustable pulse width. When the MCU outputs a PWM signal with a preset frequency and preset pulse width, the IGN self-locking circuit is broken. This solution effectively prevents other interference signals from causing the IGN to power off, improving the reliability of IGN power-on and power-off in the product.

[0004] As can be seen from the above patent, this patent uses a PWM signal to break the IGN self-locking circuit to improve the stability of IGN power-on and power-off. However, this patent does not provide a safe and reliable IGN self-locking circuit. The structure of the self-locking circuit is of great significance to the safety control of the PDU of the whole vehicle. This invention combines the method of breaking the self-locking circuit of the above patent and provides a more complete, safer and more reliable self-locking scheme, and based on this, a safe and reliable PDU safety control system is constructed. Summary of the Invention

[0005] This invention aims to overcome the shortcomings of the prior art and proposes a PDU safety control system to ensure the normal operation of the power supply system when the MCU fails and to achieve safe power-off at any time, thereby improving the overall safety and reliability.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows:

[0007] A PDU safety control system includes a controller unit, relays, a controller, and a power supply. The controller unit further includes an MCU, an IGN control circuit, a PDU backup circuit, and an MCU shutdown control circuit.

[0008] The MCU is used to output control signals to the input terminal of the IGN control circuit. The MCU also outputs signals to the MCU shutdown control circuit to start the MCU shutdown control circuit.

[0009] The PDU backup circuit is used to output a control signal to the input terminal of the IGN control circuit after receiving the feedback voltage.

[0010] The IGN control circuit is used to control the relay to turn on after receiving the control signal from the MCU or the control signal from the PDU backup circuit;

[0011] After being turned on, the relay is used to provide voltage to the controller and output feedback voltage to the PDU backup circuit;

[0012] The MCU shutdown control circuit is used to shut down the output of the PDU backup circuit after receiving a signal from the MCU.

[0013] Furthermore, the MCU is connected to the input terminals of the IGN control circuit and the MCU shutdown control circuit, respectively; the output terminal of the MCU shutdown control circuit is connected to the input terminal of the PDU backup circuit; the output terminal of the PDU backup circuit is also connected to the input terminal of the IGN control circuit; one end of the relay coil is connected to the output terminal of the IGN control circuit, and the other end is connected to the positive terminal of the power supply; the output terminal of the relay is connected to the controller and the PDU backup circuit, respectively.

[0014] Furthermore, the power supply voltage is KL30.

[0015] Furthermore, the PDU backup circuit includes resistors R1, R2, R3, and R4, capacitors C1 and C2, a PNP transistor Q1, and an N-type MOSFET Q2. One end of resistor R1 is connected to the feedback voltage, and the other end is connected to the input terminal of the PDU backup circuit. The first end of capacitor C1 is connected to the input terminal of the PDU backup circuit, and the second end of capacitor C1 is grounded. The first end of resistor R2 is connected to the first end of capacitor C1, and the second end of resistor R2 is grounded. The N-type MOSFET Q2... The gate of transistor Q2 is connected to the first terminal of resistor R2, the source is grounded, and the drain is connected to the base of PNP transistor Q1 through resistor R3. The emitter of PNP transistor Q1 is connected to positive 5V. One end of resistor R4 is connected to the emitter of PNP transistor Q1, and the other end is connected to the base of PNP transistor Q1. The first terminal of capacitor C2 is connected to the collector of PNP transistor Q1, the second terminal of capacitor C2 is grounded, and the first terminal of capacitor C2 is also connected to the output terminal of PDU backup circuit.

[0016] The MCU shutdown control circuit includes resistors R5 and R6, capacitors C3 and C4, a switching diode D1, and an N-type MOSFET Q3. The common terminal of the switching diode D1 is connected to the input terminal of the MCU shutdown control circuit via capacitor C3. One end of resistor R5 is connected to the input terminal of the MCU shutdown control circuit, and the other end is grounded. The first end of capacitor C4 is connected to the negative terminal of the switching diode D1, and the second end of capacitor C4 is grounded and also connected to the positive terminal of the switching diode D1. The first end of resistor R6 is connected to the first end of capacitor C4, and the second end of resistor R6 is grounded. The gate of the N-type MOSFET Q3 is connected to the first segment of resistor R6, the source is grounded, and the drain is connected to the output terminal of the MCU shutdown control circuit. The N-type MOSFETs Q2 and Q3 are of model NX7002BKW, the switching diode D1 is of model BAV99, and the PNP transistor Q1 is of model PDTA114YU.

[0017] The IGN control circuit includes a power driver chip, resistors R7, R8, and R9, capacitors C5 and C6, and a switching diode D2. The MCU control signal is output to the input terminal of the power driver chip via resistor R7. The output terminal of the PDU backup circuit is connected to the input terminal of the power driver chip via the switching diode D2. The drain terminal of the power driver chip serves as the control signal output terminal of the IGN control circuit. The first terminal of capacitor C5 is connected to the drain terminal of the power driver chip, and the second terminal of capacitor C5 is grounded. The first terminal of resistor R8 is connected to the first terminal of capacitor C5, and the second terminal of resistor R8 is connected to the diagnostic signal output terminal of the IGN control circuit. The first terminal of resistor R9 is connected to the second terminal of resistor R8, and the second terminal is grounded. The first terminal of capacitor C6 is connected to the first terminal of resistor R9, and the second terminal of capacitor C6 is grounded. The source terminal of the power driver chip is grounded. The input, drain, and source terminals of the power driver chip are a set of pins on the same side. The power driver chip is selected as VNLD5300-E, and the switching diode D2 is selected as BAV21WS.

[0018] Furthermore, the MCU outputs a PWM signal to activate the MCU shutdown control circuit.

[0019] The technical effects of the present invention are as follows: (1) When the MCU fails to output control signals to the IGN control circuit, the PDU backup circuit continues to output control signals to achieve the backup effect, ensuring the normal operation of the system; (2) Under normal circumstances, when the system wants to power down, the MCU shuts down the output to the IGN control circuit and sends a PWM signal to the MCU shutdown circuit to shut down the output of the PDU backup circuit, thus realizing the normal power-down function; (3) The implementation of the above circuit improves the safety and reliability of the PDU control system. Attached Figure Description

[0020] Figure 1 This is a system block diagram of a PDU safety control system according to the present invention;

[0021] Figure 2 This is a PDU backup circuit diagram of a PDU safety control system according to the present invention;

[0022] Figure 3 This is a circuit diagram of the MCU shutdown control circuit of a PDU safety control system according to the present invention;

[0023] Figure 4 This is a circuit diagram of the IGN control circuit of a PDU safety control system according to the present invention.

[0024] The following are the labels in the diagram: R1, R2, R3, R4, R5, R6, R7, R8, and R9 are resistors; C1, C2, C3, C4, C5, and C6 are capacitors; D1 and D2 are switching diodes; Q1 is a PNP transistor; and Q2 and Q3 are N-type MOSFETs. Detailed Implementation

[0025] The specific embodiments of the present invention will be further described in detail below with reference to the accompanying drawings, in order to help those skilled in the art to have a more complete, accurate and in-depth understanding of the inventive concept and technical solution of the present invention, and to facilitate its implementation.

[0026] This system is a safety-optimized version of the traditional PDU control system and can be applied to currently used PDU control systems.

[0027] A PDU safety control system, such as Figure 1 As shown, the system includes a controller unit, relays, a controller, and a power supply. The controller unit further includes an MCU, an IGN control circuit, a PDU backup circuit, and an MCU shutdown control circuit, wherein:

[0028] The MCU is used to output control signals to the input terminal of the IGN control circuit. The MCU also outputs signals to the MCU shutdown control circuit to start the MCU shutdown control circuit.

[0029] The PDU backup circuit is used to output a control signal to the input terminal of the IGN control circuit after receiving the feedback voltage.

[0030] The IGN control circuit is used to control the relay to turn on after receiving the control signal from the MCU or the control signal from the PDU backup circuit;

[0031] After being turned on, the relay is used to provide voltage to the controller and output feedback voltage to the PDU backup circuit;

[0032] The MCU shutdown control circuit is used to shut down the output of the PDU backup circuit after receiving a signal from the MCU.

[0033] Furthermore, the MCU is connected to the input terminals of the IGN control circuit and the MCU shutdown control circuit, respectively; the output terminal of the MCU shutdown control circuit is connected to the input terminal of the PDU backup circuit; the output terminal of the PDU backup circuit is also connected to the input terminal of the IGN control circuit; one end of the relay coil is connected to the output terminal of the IGN control circuit, and the other end is connected to the positive terminal of the power supply (in this embodiment, the controller unit is powered by the vehicle battery, and the power supply voltage is KL30); the output terminal of the relay is connected to the controller and the PDU backup circuit, respectively.

[0034] In this solution, the controller unit can be a standalone starter controller or body controller with only this function, or it can be integrated into other controllers, i.e., an integrated body controller. This invention relates to the application of PDU safety control through a PDU backup circuit when the MCU in the controller unit experiences an abnormal state. When the PDU is normally powered on, the controller unit controls the IGN control circuit to be energized. When the controller unit malfunctions and the MCU stops outputting control signals to the IGN control circuit, the PDU backup lock-up circuit activates, allowing the IGN control circuit to continue outputting, preventing power loss and ensuring safety. When the PDU needs to be powered down under normal power-on conditions, the MCU controls the MCU to shut down the control circuit via a PWM signal, causing the PDU backup lock-up circuit to deactivate, and then performs the power-down action, stopping the IGN control circuit from outputting.

[0035] Specifically, such as Figure 2As shown, the PDU backup circuit includes a 270KR resistor R1, a 150KR resistor R2, a 10KR resistor R3, a 47KR resistor R4, a 1uF capacitor C1, a 100nF capacitor C2, a PNP transistor Q1 (model PDTA114YU in this embodiment), and an N-type MOSFET Q2 (model NX7002BKW in this embodiment). One end of resistor R1 is connected to the feedback voltage, and the other end is connected to the input terminal of the PDU backup circuit. The first end of capacitor C1 is connected to the input terminal of the PDU backup circuit, and the second end of capacitor C1 is grounded. The first terminal of resistor R2 is connected to the first terminal of capacitor C1, and the second terminal of resistor R2 is grounded. The gate of the N-type MOSFET Q2 is connected to the first terminal of resistor R2, the source is grounded, and the drain is connected to the base of the PNP transistor Q1 through resistor R3. The emitter of the PNP transistor Q1 is connected to a positive 5V voltage. One end of resistor R4 is connected to the emitter of the PNP transistor Q1, and the other end is connected to the base of the PNP transistor Q1. The first terminal of capacitor C2 is connected to the collector of the PNP transistor Q1, the second terminal of capacitor C2 is grounded, and the first terminal of capacitor C2 is also connected to the output terminal of the PDU backup circuit.

[0036] like Figure 3 As shown, the MCU shutdown control circuit includes a 6.8KR resistor R5, a 1MR resistor R6, a 10nF capacitor C3, a 220nF capacitor C4, a switching diode D1 (model BAV99 in this embodiment), and an N-type MOSFET Q3 (model NX7002BKW in this embodiment). The common terminal of the switching diode D1 is connected to the input terminal of the MCU shutdown control circuit via capacitor C3. One end of resistor R5 is connected to the input terminal of the MCU shutdown control circuit, and the other end is grounded. The first end of capacitor C4 is connected to the negative terminal of switching diode D1, and the second end of capacitor C4 is grounded. The second end of capacitor C4 is also connected to the positive terminal of switching diode D1. The first end of resistor R6 is connected to the first end of capacitor C4, and the second end of resistor R6 is grounded. The gate of the N-type MOSFET Q3 is connected to the first segment of resistor R6, the source is grounded, and the drain is connected to the output terminal of the MCU shutdown control circuit.

[0037] like Figure 4As shown, the IGN control circuit includes a power driver chip VNLD5300-E, a 40KR resistor R7, a 400KR resistor R8, a 188KR resistor R9, a 10nF capacitor C5, a 1nF capacitor C6, and a switching diode D2 (model BAV21WS in this embodiment). The MCU control signal is output to the input terminal of the power driver chip via resistor R7; the output terminal of the PDU backup circuit is connected to the input terminal of the power driver chip via the switching diode D2; and the drain terminal of the power driver chip serves as the IGN control signal. The control signal output terminal of the GN control circuit; the first terminal of capacitor C5 is connected to the drain terminal of the power driver chip, and the second terminal of capacitor C5 is grounded; the first terminal of resistor R8 is connected to the first terminal of capacitor C5, and the second terminal of resistor R8 is connected to the diagnostic signal output terminal of the IGN control circuit; the first terminal of resistor R9 is connected to the second terminal of resistor R8, and the second terminal is grounded; the first terminal of capacitor C6 is connected to the first terminal of resistor R9, and the second terminal of capacitor C6 is grounded; the source terminal of the power driver chip is grounded, and the input terminal, drain terminal, and source terminal of the power driver chip are a set of pins on the same side.

[0038] This PDU safety system primarily achieves PDU safety control through a PDU hardware backup circuit. The MCU outputs a PWM signal to control the MCU shutdown control circuit, which then shuts down the PDU backup circuit. In actual implementation, when the system powers on, the MCU outputs a valid 5V level via IGN1_CONTROL_OUT, controlling the IGN control circuit to output a low level, causing the external relay to engage. After the external relay engages, the entire controller is powered on by the KL30 power supply, simultaneously forming an IGN feedback voltage output to the PDU backup circuit. Upon receiving the feedback voltage, the PNP transistor Q1 and N-type MOSFET Q2 of the PDU backup circuit conduct. The PDU backup circuit outputs a 5V level via PDU_LIMPHOME_OUT, giving the ING control circuit two 5V controls: one from the MCU output IGN1_CONTROL_OUT and the other from the PDU backup circuit output PDU_LIMPHOME_OUT. This achieves a safety backup control effect, improving the system's safety and reliability.

[0039] When the MCU receives a power-down command, it must first shut down the PDU backup circuit before turning off the IGN control circuit output. Specifically, after receiving the power-down command, one of the MCU's control output terminals outputs a PWM signal to the input terminal of the MCU shutdown control circuit via BACKUP_SW. The PWM signal, through the switching diode D1, turns on the N-type MOSFET Q3. After Q3 turns on, the output terminal of the MCU shutdown control circuit is grounded through the source of Q3. At this time, the output terminal of the MCU shutdown control circuit, through BACKUP_DISABLE, is at a low level. The low level of BACKUP_DISABLE is input to the PDU backup circuit, causing the N-type MOSFET Q2 of the PDU backup circuit to turn off. The non-conducting N-type MOSFET Q2, in turn, causes the PNP transistor Q1 of the PDU backup circuit to not work. Therefore, the output terminal of the PDU backup circuit has no output through PDU_LIMPHOME_OUT, meaning the PDU backup circuit is not working. Then, the MCU turns off the output of the IGN control circuit through IGN1_CONTROL_OUT, thus achieving a safe power-down of the system.

[0040] In the event of MCU failure when the controller unit outputs through the IGN control circuit, this invention forms a closed-loop lockout circuit through the output feedback of the IGN control circuit. This provides an additional backup output for the IGN control circuit, ensuring the safety of the IGN control circuit output and protecting the user's safety. Furthermore, it provides a method for the system to safely power down using a PWM signal, improving the overall system's safety and reliability. The invention has been described above with reference to the accompanying drawings. Obviously, the specific implementation of this invention is not limited to the above-described manner. Any non-substantial improvements made using the inventive concept and technical solution, or the direct application of the above-described concept and technical solution to other situations without modification, are all within the protection scope of this invention.

Claims

1. A PDU safety control system, characterized in that: The system includes a controller unit, relays, a controller, and a power supply. The controller unit further includes an MCU, an IGN control circuit, a PDU backup circuit, and an MCU shutdown control circuit, wherein: The MCU is used to output control signals to the input terminal of the IGN control circuit. The MCU also outputs signals to the MCU shutdown control circuit to start the MCU shutdown control circuit. The PDU backup circuit is used to output a control signal to the input terminal of the IGN control circuit after receiving the feedback voltage. The IGN control circuit is used to control the relay to turn on after receiving the control signal from the MCU or the control signal from the PDU backup circuit; After being turned on, the relay is used to provide voltage to the controller and output feedback voltage to the PDU backup circuit; The MCU shutdown control circuit is used to shut down the output of the PDU backup circuit after receiving a signal from the MCU. The PDU backup circuit includes resistors (R1), (R2), (R3), and (R4), capacitors (C1) and (C2), a PNP transistor (Q1), and an N-type MOSFET (Q2). One end of resistor (R1) is connected to the feedback voltage, and the other end is connected to the input terminal of the PDU backup circuit. The first end of capacitor (C1) is connected to the input terminal of the PDU backup circuit, and the second end of capacitor (C1) is grounded. The first end of resistor (R2) is connected to the first end of capacitor (C1), and the second end of resistor (R2) is grounded. The N-type MOSFET... The gate of the OS transistor (Q2) is connected to the first terminal of the resistor (R2), the source is grounded, and the drain is connected to the base of the PNP transistor (Q1) through the resistor (R3). The emitter of the PNP transistor (Q1) is connected to a positive 5V voltage. One end of the resistor (R4) is connected to the emitter of the PNP transistor (Q1), and the other end is connected to the base of the PNP transistor (Q1). The first terminal of the capacitor (C2) is connected to the collector of the PNP transistor (Q1), and the second terminal of the capacitor (C2) is grounded. The first terminal of the capacitor (C2) is also connected to the output terminal of the PDU backup circuit.

2. The PDU safety control system according to claim 1, characterized in that: The MCU is connected to the input terminals of the IGN control circuit and the MCU shutdown control circuit, respectively; the output terminal of the MCU shutdown control circuit is connected to the input terminal of the PDU backup circuit; the output terminal of the PDU backup circuit is also connected to the input terminal of the IGN control circuit; one end of the relay coil is connected to the output terminal of the IGN control circuit, and the other end is connected to the positive terminal of the power supply; the output terminal of the relay is connected to the controller and the PDU backup circuit, respectively.

3. A PDU safety control system according to claim 1 or 2, characterized in that: The power supply voltage is KL30.

4. A PDU safety control system according to claim 1, characterized in that: The MCU shutdown control circuit includes resistors (R5), (R6), capacitors (C3), (C4), a switching diode (D1), and an N-type MOSFET (Q3). The common terminal of the switching diode (D1) is connected to the input terminal of the MCU shutdown control circuit via capacitor (C3). One end of resistor (R5) is connected to the input terminal of the MCU shutdown control circuit, and the other end is grounded. The first end of capacitor (C4) is connected to the negative terminal of switching diode (D1), and the second end of capacitor (C4) is grounded and also connected to the positive terminal of switching diode (D1). The first end of resistor (R6) is connected to the first end of capacitor (C4), and the second end of resistor (R6) is grounded. The gate of the N-type MOSFET (Q3) is connected to the first end of resistor (R6), the source is grounded, and the drain is connected to the output terminal of the MCU shutdown control circuit.

5. A PDU safety control system according to claim 4, characterized in that: The N-type MOSFET is model number NX7002BKW, and the PNP-type transistor is model number PDTA114YU.

6. A PDU safety control system according to claim 4, characterized in that: The switching diode (D1) is model BAV99.

7. A PDU safety control system according to claim 1, characterized in that: The IGN control circuit includes a power driver chip, resistors (R7), (R8), and (R9), capacitors (C5) and (C6), and a switching diode (D2). The MCU control signal is output to the input terminal of the power driver chip via resistor (R7); the output terminal of the PDU backup circuit is connected to the input terminal of the power driver chip via the switching diode (D2); the drain terminal of the power driver chip serves as the control signal output terminal of the IGN control circuit; the first terminal of capacitor (C5) is connected to… The drain terminal of the power driver chip is connected, and the second terminal of the capacitor (C5) is grounded; the first terminal of the resistor (R8) is connected to the first terminal of the capacitor (C5), and the second terminal of the resistor (R8) is connected to the diagnostic signal output terminal of the IGN control circuit; the first terminal of the resistor (R9) is connected to the second terminal of the resistor (R8), and the second terminal is grounded; the first terminal of the capacitor (C6) is connected to the first terminal of the resistor (R9), and the second terminal of the capacitor (C6) is grounded; the source terminal of the power driver chip is grounded, and the input terminal, drain terminal, and source terminal of the power driver chip are a set of pins on the same side.

8. A PDU safety control system according to claim 7, characterized in that: The power driver chip is selected as VNLD5300-E, and the switching diode (D2) is selected as BAV21WS.

9. A PDU safety control system according to any one of claims 1, 4, 5, and 6, characterized in that: The MCU outputs a PWM signal to start the MCU shutdown control circuit.

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