A hardware safety protection circuit for a steer-by-wire system

Abstract

The hardware safety protection circuit for the steer-by-wire system provided by this utility model includes a power supply chip, a microcontroller unit, a dual transistor conversion circuit, and a dual MOSFET switching circuit. The dual transistor conversion circuit is connected to the power supply chip via a first line and to the microcontroller unit via a second line. The output of the dual transistor conversion circuit is connected to the input of the dual MOSFET switching circuit, and the output of the dual MOSFET switching circuit is connected to the input of the controlled circuit. When the power supply chip and / or the microcontroller unit detect a hardware abnormality, they each send an independent disconnect signal to the dual transistor conversion circuit. The dual transistor conversion circuit receives these signals and converts them into a unified control signal, which is then sent to the dual MOSFET switching circuit. This causes the dual MOSFET switching circuit to disconnect the controlled circuit and stop its operation, thus achieving multiple layers of hardware protection.

Description

Technical Field

[0001] This utility model relates to the field of steer-by-wire technology, specifically to a hardware safety protection circuit for a steer-by-wire system. Background Technology

[0002] Steer-by-wire is a new type of steering technology that achieves steering through electronic signal transmission and electric drive actuators. It eliminates the need for a mechanical connection between the steering wheel and the steering wheels, which greatly simplifies the structure of the steering system, reduces weight and noise, and is increasingly widely used in the automotive and other fields.

[0003] The working principle of the steer-by-wire system is as follows: when the driver turns the steering wheel, the steering wheel sensor transmits the collected signals such as steering angle and torque to the electronic control unit (ECU). After calculation and processing, the ECU sends control commands to the steering motor to drive the steering wheels to achieve steering action. However, this technology is highly dependent on electronic technology and software control system. Failure of electronic components, electromagnetic interference, software vulnerabilities, etc. may cause system abnormalities, affecting the normal driving and safety of the vehicle, which makes the safety and reliability of this technology face severe challenges. Utility Model Content

[0004] The purpose of this invention is to overcome one or more shortcomings in the prior art and provide a hardware safety protection circuit for a steer-by-wire system.

[0005] To achieve the above objectives, the technical solution adopted by this utility model is a hardware safety protection circuit for a steer-by-wire system, including a power supply chip and a microcontroller unit (MCU), as well as a dual transistor conversion circuit and a dual MOSFET switching circuit. The dual transistor conversion circuit is connected to the power supply chip via a first line and is also connected to the microcontroller unit via a second line. The output terminal of the dual transistor conversion circuit is connected to the input terminal of the dual MOSFET switching circuit, and the output terminal of the dual MOSFET switching circuit is connected to the input terminal of the controlled circuit.

[0006] When the power chip and / or microcontroller detect a hardware malfunction, it can send a disconnect signal to the dual transistor switching circuit. The dual transistor switching circuit receives the signal and converts it into a control signal, which is then sent to the dual MOSFET switching circuit. The dual MOSFET switching circuit controls the controlled circuit to disconnect, thus achieving multiple protections for the hardware.

[0007] Preferably, the dual transistor conversion circuit includes transistor A and transistor B. The base of transistor A is connected to the first circuit, the emitter of transistor A is grounded, the collector of transistor A is connected to the base of transistor B, the emitter of transistor B is connected to the second circuit, and the collector of transistor B is led out to form the output terminal of the dual transistor conversion circuit.

[0008] More preferably, the dual transistor switching circuit further includes resistors R1 to R4. One end of resistor R1 is connected to the first line, and the other end is connected to the ground line of the emitter of transistor A. Resistor R2 is connected in series in the connection line between the collector of transistor A and the base of transistor B. One end of resistor R3 is connected to the second line, and the other end is connected to the connection line between the collector of transistor A and the base of transistor B, and is located on the side of resistor R2 closer to the base of transistor B. Resistor R4 is connected in series in the lead-out line of the collector of transistor B.

[0009] Preferably, the dual MOS transistor switching circuit includes MOS transistor A and MOS transistor B. The gate of MOS transistor A is connected to the output terminal of the dual transistor switching circuit, the drain of MOS transistor A is connected to the gate of MOS transistor B, the source of MOS transistor A is connected to the source of MOS transistor B and grounded, and the drain of MOS transistor B is led out to form the output terminal of the dual MOS transistor switching circuit.

[0010] More preferably, the dual MOS transistor switching circuit further includes resistors R5 to R7. One end of resistor R5 is connected in parallel to the connection line between the gate of MOS transistor A and the output terminal of the dual transistor conversion circuit, and the other end is connected in parallel to the connection line between the source of MOS transistor A and the source of MOS transistor B. Resistor R6 is connected in series in parallel to the connection line between the drain of MOS transistor A and the gate of MOS transistor B. One end of resistor R7 is connected in parallel to the connection line between the source of MOS transistor A and the source of MOS transistor B, and the other end is connected in parallel to the connection line between the drain of MOS transistor A and the gate of MOS transistor B, and is located on the side of resistor R6 closer to MOS transistor B.

[0011] More preferably, the dual MOS transistor switching circuit further includes a diode A, the anode of which is connected to the connection line between the drain of MOS transistor A and the gate of MOS transistor B, and is located on the side of resistor R6 close to MOS transistor A, and the cathode of which is connected to the connection line between the source of MOS transistor A and the source of MOS transistor B.

[0012] More preferably, the dual MOS transistor switching circuit further includes resistors R8 and R9. One end of resistor R8 is connected to the drain of MOS transistor A, and the other end is connected to the line supplying external VCC voltage. One end of resistor R9 is connected to the lead-out line from the drain of MOS transistor B, and the other end is connected to the line supplying external VDD voltage.

[0013] Preferably, the power chip and the microcontroller are connected via a third line signal.

[0014] Preferably, the hardware safety protection circuit of the steer-by-wire system further includes a feedback circuit, the input terminal of which is connected in parallel to the connection line between the dual MOS transistor switching circuit and the controlled circuit, and the output terminal is connected to the microcontroller unit via a fourth line.

[0015] More preferably, the feedback circuit includes a resistor R10 connected in series on the fourth line, and a resistor R11, a capacitor C, and a diode B connected in parallel in sequence. One end of the parallel connection of resistor R11, capacitor C, and diode B is connected to the fourth line and located on the side of resistor R10 closer to the microcontroller unit, while the other end is grounded.

[0016] Due to the application of the above technical solution, this utility model has the following advantages compared with the prior art:

[0017] The hardware safety protection circuit for the steer-by-wire system provided by this utility model includes a power supply chip, a microcontroller unit, a dual transistor conversion circuit, and a dual MOSFET switching circuit. The dual transistor conversion circuit is connected to the power supply chip via a first line and to the microcontroller unit via a second line. The output of the dual transistor conversion circuit is connected to the input of the dual MOSFET switching circuit, and the output of the dual MOSFET switching circuit is connected to the input of the controlled circuit. When the power supply chip and / or the microcontroller unit detect a hardware abnormality, they each send an independent disconnect signal to the dual transistor conversion circuit. The dual transistor conversion circuit receives these signals and converts them into a unified control signal, which is then sent to the dual MOSFET switching circuit. This causes the dual MOSFET switching circuit to disconnect the controlled circuit and stop its operation, achieving multiple protections for the hardware and improving the overall safety of the steer-by-wire system. Furthermore, the power supply chip's signal transmission does not need to pass through the microcontroller unit, resulting in a faster response speed and stronger protection capability. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of a preferred embodiment of the present invention.

[0019] Figure 2 yes Figure 1 The detailed structural diagram of the dual transistor switching circuit.

[0020] Figure 3 yes Figure 1 The detailed structure diagram of the dual MOS transistor switching circuit.

[0021] Figure 4 yes Figure 1 The specific structural diagram of the feedback circuit.

[0022] Among them: 10. Power chip; 11. First circuit; 12. Third circuit; 20. Microcontroller unit; 21. Second circuit; 22. Fourth circuit; 30. Dual transistor switching circuit; 31. Transistor A; 32. Transistor B; 40. Dual MOSFET switching circuit; 41. MOSFET A; 42. MOSFET B; 43. Diode A; 50. Controlled circuit; 60. Feedback circuit; 61. Diode B. Detailed Implementation

[0023] like Figures 1 to 4 As shown, the hardware safety protection circuit for the steer-by-wire system provided by this utility model includes a power supply chip 10, a microcontroller unit 20, a dual transistor conversion circuit 30, and a dual MOSFET switching circuit 40. The dual transistor conversion circuit 30 is connected to the power supply chip 10 via a first line 11 and to the microcontroller unit 20 via a second line 21. The output terminal of the dual transistor conversion circuit 30 is connected to the input terminal of the dual MOSFET switching circuit 40, and the output terminal of the dual MOSFET switching circuit 40 is connected to the input terminal of the controlled circuit 50. When the power supply chip 10 and / or the microcontroller unit 20 detect a hardware abnormality (such as hardware overcurrent or overvoltage), they send a disconnect signal to the dual transistor conversion circuit 30. The dual transistor conversion circuit 30 receives this signal and converts it into a control signal, which is then sent to the dual MOSFET switching circuit 40. The dual MOSFET switching circuit 40 controls the controlled circuit 50 to disconnect, thus achieving multiple protections for the hardware.

[0024] The advantage of this setup is that when the power chip and / or microcontroller detect a hardware malfunction, they can each send an independent disconnect signal to the dual transistor conversion circuit. The dual transistor conversion circuit receives these signals and converts them into a unified control signal, which is then sent to the dual MOSFET switching circuit. This causes the dual MOSFET switching circuit to disconnect the controlled circuit and stop its operation, thus achieving multiple protections for the hardware and improving the overall safety of the steer-by-wire system. At the same time, the power chip does not need to send signals through the microcontroller, resulting in a faster response speed and stronger protection capabilities.

[0025] In this embodiment, the dual transistor conversion circuit 30 includes transistor A and transistor B. The base of transistor A is connected to the first line 11, the emitter of transistor A is grounded, the collector of transistor A is connected to the base of transistor B, the emitter of transistor B is connected to the second line 21, and the collector of transistor B is led outward to form the output terminal of the dual transistor conversion circuit 30. Further, the dual transistor conversion circuit 30 also includes resistors R1 to R4. One end of resistor R1 is connected to the first line, and the other end is connected to the ground line of the emitter of transistor A. Resistor R2 is connected in series in the connection line between the collector of transistor A and the base of transistor B. One end of resistor R3 is connected to the second line 21, and the other end is connected to the connection line between the collector of transistor A and the base of transistor B, and is located on the side of resistor R2 closer to the base of transistor B. Resistor R4 is connected in series in the lead-out line of the collector of transistor B.

[0026] In this embodiment, the dual MOSFET switching circuit 40 includes MOSFET A and MOSFET B. The gate of MOSFET A is connected to the output terminal of the dual transistor conversion circuit 30, the drain of MOSFET A is connected to the gate of MOSFET B, the source of MOSFET A is connected to the source of MOSFET B and grounded, and the drain of MOSFET B is led out to form the output terminal of the dual MOSFET switching circuit 40. Specifically, the dual MOSFET switching circuit 40 also includes resistors R5 to R7. One end of resistor R5 is connected in parallel to the connection line between the gate of MOSFET A and the output terminal of the dual transistor conversion circuit 30, and the other end is connected in parallel to the connection line between the source of MOSFET A and the source of MOSFET B. Resistor R6 is connected in series in parallel to the connection line between the drain of MOSFET A and the gate of MOSFET B, and one end of resistor R7 is connected in parallel to the output terminal of MOSFET B. The source of S-transistor A is connected to the source of MOSFET B, and the other end is connected to the connection line between the drain of MOSFET A and the gate of MOSFET B, located on the side of resistor R6 near MOSFET B. Further, the dual MOSFET switching circuit 40 also includes diode A, resistor R8 and resistor R9. The anode of diode A is connected to the connection line between the drain of MOSFET A and the gate of MOSFET B, located on the side of resistor R6 near MOSFET A. The cathode of diode A is connected to the connection line between the source of MOSFET A and the source of MOSFET B. One end of resistor R8 is connected to the drain of MOSFET A, and the other end is connected to the line supplying external VCC voltage. One end of resistor R9 is connected to the lead-out line from the drain of MOSFET B, and the other end is connected to the line supplying external VDD voltage.

[0027] In this embodiment, the power chip 10 and the microcontroller unit 20 are connected via a third line 12. The advantage of this arrangement is that when the power chip 10 detects a hardware malfunction, it will also send a signal to the microcontroller unit 20. If the power chip 10 fails to send a disconnect signal via the first line 11, the microcontroller unit 20 can still send a disconnect signal via the second line 21 to ensure that the controlled circuit 50 can stop operating, thereby achieving hardware protection.

[0028] To detect whether the dual MOSFET switching circuit 40 has successfully sent a control signal to the controlled circuit 50, the hardware safety protection circuit of the steer-by-wire system also includes a feedback circuit 60. The input terminal of the feedback circuit 60 is connected in parallel to the connection line between the dual MOSFET switching circuit 40 and the controlled circuit 50, and the output terminal is connected to the microcontroller unit 20 via the fourth line 22. Specifically, the feedback circuit 60 includes a resistor R10 connected in series on the fourth line 22, and a resistor R11, a capacitor C, and a diode B connected in parallel in sequence. One end of the parallel connection of the resistor R11, capacitor C, and diode B is connected in parallel to the fourth line 22 and is located on the side of the resistor R10 closer to the microcontroller unit 20, while the other end is grounded.

[0029] The hardware safety protection circuit for the steer-by-wire system provided by this utility model is controlled by signals from the power supply chip and the microcontroller unit. When the power supply chip detects overcurrent or overvoltage faults in the hardware, it sends a warning signal to the microcontroller unit and simultaneously sets the level of the first line high, turning on the two transistors in the dual transistor switching circuit. This pulls down the gate level of MOSFET A in the dual MOSFET switching circuit, turning off MOSFET A, and pulls up the gate level of MOSFET B in the dual MOSFET switching circuit, turning on MOSFET B. This pulls down the signal level at the drain of MOSFET B, thus... The controlled circuit enabled by this signal is de-energized and stops operating, thus protecting the overall system from damage due to faults. At the same time, the microcontroller can also send a disconnect signal through the second line to stop the operation of the controlled circuit. Specifically, when the microcontroller detects an abnormality, it sends a low-level signal through the second line, pulling down the gate level of MOSFET A in the dual MOSFET switching circuit, turning MOSFET A off, and pulling up the gate level of MOSFET B, turning MOSFET B on. This pulls down the signal level connected to the drain of MOSFET B, causing the controlled circuit enabled by this signal to be de-energized and stop operating.

[0030] Since the disconnect signal sent by the power chip does not need to be relayed through the microcontroller unit, the hardware protection time is greatly shortened, the timeliness is greatly improved, and the protection capability of the hardware system is stronger. At the same time, when an abnormality occurs that the power chip cannot detect but the microcontroller unit can detect, the microcontroller unit can also directly interrupt the circuit operation, thus achieving multiple insurances in circuit protection.

[0031] The above embodiments are only for illustrating the technical concept and features of this utility model. Their purpose is to enable those skilled in the art to understand the content of this utility model and implement it accordingly. They should not be used to limit the protection scope of this utility model. All equivalent changes or modifications made in accordance with the spirit and essence of this utility model should be included within the protection scope of this utility model.

Claims

1. A hardware safety protection circuit for a steer-by-wire system, comprising a power supply chip and a microcontroller unit, characterized in that: It also includes a dual transistor conversion circuit and a dual MOSFET switching circuit. The dual transistor conversion circuit is connected to the power chip signal via a first line, and the dual transistor conversion circuit is also connected to the microcontroller signal via a second line. The output terminal of the dual transistor conversion circuit is connected to the input terminal of the dual MOSFET switching circuit, and the output terminal of the dual MOSFET switching circuit is connected to the input terminal of the controlled circuit. When the power chip and / or microcontroller detect a hardware malfunction, it can send a disconnect signal to the dual transistor switching circuit. The dual transistor switching circuit receives the signal and converts it into a control signal, which is then sent to the dual MOSFET switching circuit. The dual MOSFET switching circuit controls the controlled circuit to disconnect, thus achieving multiple protections for the hardware.

2. The hardware safety protection circuit for the steer-by-wire system according to claim 1, characterized in that: The dual transistor conversion circuit includes transistor A and transistor B. The base of transistor A is connected to the first circuit, the emitter of transistor A is grounded, the collector of transistor A is connected to the base of transistor B, the emitter of transistor B is connected to the second circuit, and the collector of transistor B is led out to form the output terminal of the dual transistor conversion circuit.

3. The hardware safety protection circuit for the steer-by-wire system according to claim 2, characterized in that: The dual transistor switching circuit also includes resistors R1 to R4. One end of resistor R1 is connected to the first line, and the other end is connected to the ground line of the emitter of transistor A. Resistor R2 is connected in series in the connection line between the collector of transistor A and the base of transistor B. One end of resistor R3 is connected to the second line, and the other end is connected to the connection line between the collector of transistor A and the base of transistor B, and is located on the side of resistor R2 closer to the base of transistor B. Resistor R4 is connected in series in the lead-out line of the collector of transistor B.

4. The hardware safety protection circuit for the steer-by-wire system according to claim 1, characterized in that: The dual MOS transistor switching circuit includes MOS transistor A and MOS transistor B. The gate of MOS transistor A is connected to the output terminal of the dual transistor switching circuit. The drain of MOS transistor A is connected to the gate of MOS transistor B. The source of MOS transistor A is connected to the source of MOS transistor B and grounded. The drain of MOS transistor B is led out to form the output terminal of the dual MOS transistor switching circuit.

5. The hardware safety protection circuit for the steer-by-wire system according to claim 4, characterized in that: The dual MOS transistor switching circuit also includes resistors R5 to R7. One end of resistor R5 is connected in parallel to the connection line between the gate of MOS transistor A and the output terminal of the dual transistor conversion circuit, and the other end is connected in parallel to the connection line between the source of MOS transistor A and the source of MOS transistor B. Resistor R6 is connected in series in parallel to the connection line between the drain of MOS transistor A and the gate of MOS transistor B. One end of resistor R7 is connected in parallel to the connection line between the source of MOS transistor A and the source of MOS transistor B, and the other end is connected in parallel to the connection line between the drain of MOS transistor A and the gate of MOS transistor B, and is located on the side of resistor R6 closer to MOS transistor B.

6. The hardware safety protection circuit for the steer-by-wire system according to claim 5, characterized in that: The dual MOS transistor switching circuit also includes diode A. The anode of diode A is connected in parallel to the connection line between the drain of MOS transistor A and the gate of MOS transistor B, and is located on the side of resistor R6 close to MOS transistor A. The cathode of diode A is connected in parallel to the connection line between the source of MOS transistor A and the source of MOS transistor B.

7. The hardware safety protection circuit for the steer-by-wire system according to claim 5, characterized in that: The dual MOS transistor switching circuit also includes resistors R8 and R9. One end of resistor R8 is connected to the drain of MOS transistor A, and the other end is connected to the line supplying external VCC voltage. One end of resistor R9 is connected to the lead-out line from the drain of MOS transistor B, and the other end is connected to the line supplying external VDD voltage.

8. The hardware safety protection circuit for the steer-by-wire system according to claim 1, characterized in that: The power chip and the microcontroller are connected via a third line signal.

9. The hardware safety protection circuit for the steer-by-wire system according to claim 1, characterized in that: The hardware safety protection circuit of the steer-by-wire system also includes a feedback circuit. The input terminal of the feedback circuit is connected in parallel to the connection line between the dual MOS transistor switching circuit and the controlled circuit, and the output terminal is connected to the microcontroller unit via a fourth line.

10. The hardware safety protection circuit for the steer-by-wire system according to claim 9, characterized in that: The feedback circuit includes a resistor R10 connected in series on the fourth line, and a resistor R11, a capacitor C, and a diode B connected in parallel in sequence. One end of the parallel connection of resistor R11, capacitor C, and diode B is connected to the fourth line and located on the side of resistor R10 closer to the microcontroller unit, while the other end is grounded.

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