Complete vehicle DCDC fault state accurate reporting method and system and vehicle

Abstract

The invention discloses a whole vehicle DCDC fault state accurate reporting method and system and a vehicle, and the method comprises the steps: monitoring the voltage of a DCDC input end, the voltage of a DCDC output end and the current of the DCDC output end under the condition that the whole vehicle is powered on and the DCDC working state is normal; and if the voltage of the DCDC input end, the voltage of the DCDC output end and the current of the DCDC output end meet preset conditions, the power supply system reports a DCDC fault state to a whole vehicle controller, so that the whole vehicle controller stops sending a work request enable signal to the power supply system, and the whole vehicle is powered off. According to the method, whether a high-grade fault state occurs or not can be accurately identified, and meanwhile, after the high-grade fault state occurs, sending of a working request enable signal to a power supply system can be stopped in time, so that the DCDC is stopped in time, and the situation that after the DCDC is damaged, the DCDC is frequently requested due to the low-voltage energy supplement requirement of the whole vehicle, and high-voltage loop short-circuit ablation fire is caused by high voltage on a battery is prevented.

Description

Technical Field

[0001] The present invention relates to new energy vehicles, and in particular to a method and system for accurately reporting a DCDC fault state of a whole vehicle, and a vehicle. Background Art

[0002] With the rise of the new energy vehicle market, the safety of electric vehicles has attracted much attention. Safety issues such as electric vehicle spontaneous combustion, power interruption due to functional failure, and spontaneous combustion during charging have made the safe development of new energy electric vehicles a key to success for major car manufacturers. DCDC (also known as DC controller, DC-DC converter, etc.) is a member of the high-voltage circuit of new energy vehicles and is a key component for converting high voltage to low voltage to supply low-voltage loads. Therefore, the reliability of DCDC determines whether the low-voltage devices of the entire vehicle work reliably, which will affect charging and driving safety.

[0003] Although DCDC is a mature product with a simple structure, there are still some defects in its application in the whole vehicle. This is due to the consistency of raw materials such as high-voltage MOS tubes and chips inside DCDC. As we all know, the failure rate of electronic components cannot be 0PPM, so the work of DCDC cannot be 100% stable. Therefore, it is particularly important to avoid further damage to the whole vehicle after DCDC is damaged through software control logic. The existing DCDC software control can only monitor and protect the faults reported by DCDC, and cannot identify the faults of the internal components of DCDC that have been damaged and report them to the system for protection. Summary of the invention

[0004] In view of this, the purpose of the present invention is to provide a method, system and vehicle for accurately reporting the fault status of the DCDC of a whole vehicle, which can accurately identify whether a high-level fault state occurs. At the same time, after the high-level fault state occurs, it can promptly stop sending a work request enable signal to the power supply system, so that the DCDC stops in time, and prevent the high-voltage circuit from short-circuiting and burning due to frequent requests for DCDC and high voltage on the battery due to the low-voltage energy replenishment demand of the whole vehicle after the DCDC is damaged.

[0005] A method for accurately reporting a vehicle DCDC fault status in the present invention includes: When the vehicle is powered on and the DCDC is working normally, monitor the DCDC input voltage, DCDC output voltage and DCDC output current; If the DCDC input voltage, the DCDC output voltage and the DCDC output current meet preset conditions, the power supply system reports the DCDC fault status to the vehicle controller, so that the vehicle controller stops sending a work request enable signal to the power supply system and the vehicle is powered off.

[0006] If the DCDC input voltage, DCDC output voltage, and DCDC output current meet the preset conditions, the power supply system reports the DCDC fault status to the vehicle controller. At this time, the reported DCDC fault status is a high-level fault status, such as reporting a DCDC level 3 fault, and the power supply system reports the DCDC working status to the vehicle controller as abnormal (abnormal is Failure). After the vehicle controller receives the signal of the DCDC level 3 fault, the vehicle controller stops sending work request enable signals to the power supply system and the battery controller to power off the vehicle. Thereby, after a high-level fault status occurs, the power supply system stops sending work request enable signals to the power supply system in a timely manner, so that the DCDC stops in time, and prevents the DCDC and the battery from frequently requesting high voltage due to the low-voltage energy replenishment demand of the vehicle after the DCDC is damaged, thereby preventing the high-voltage circuit from short-circuiting and burning.

[0007] Further, the preset condition is: the DCDC input terminal voltage is greater than a first preset threshold, the DCDC output terminal voltage is lower than a second preset threshold, and the DCDC output terminal current is lower than a third preset threshold, and the duration is not less than a fourth preset threshold.

[0008] The whole vehicle will apply high voltage in both OFF and ON gears to ensure that DCDC has input energy to power the whole vehicle at low voltage. However, because DCDC and OBC are integrated together to form a power supply system, if the internal detection circuit and auxiliary power supply device of DCDC are damaged, DCDC will not be able to report its correct status, causing the whole vehicle system to continuously request work instructions and continuously apply high voltage, causing the high-voltage circuit to burn and catch fire. And because the output end of DCDC is connected to the battery, the voltage at the output end of DCDC reflects the larger of the DCDC output value and the battery voltage value, while the current at the output end of DCDC changes according to the low-voltage load (the load can be 0). In order to prevent the internal DSP chip or other control components of DCDC from being damaged, resulting in the inability of the application MCU chip to feedback the true value of the DCDC status, the DCDC input voltage U HV is greater than the first preset threshold, the DCDC output voltage U LV is lower than the second preset threshold and the DCDC output current I LV When the voltage drops below the third preset threshold and the duration is not less than the fourth preset threshold, it is determined whether the DCDC working state is normal or abnormal, and whether a high-level fault state occurs can be accurately identified. At the same time, after a high-level fault state occurs, it can promptly stop sending a work request enable signal to the power supply system and the battery controller, so that the DCDC is stopped in time and the high-voltage relay of the power battery is disconnected in time, to prevent frequent requests for high voltage from being applied to the DCDC and the battery due to low-voltage energy replenishment needs of the whole vehicle after the DCDC is damaged, thereby preventing the high-voltage circuit from short-circuiting and burning.

[0009] Further, the monitoring of the DCDC input voltage, the DCDC output voltage and the DCDC output current is performed by the power supply system, and the power supply system includes a DCDC, and the DCDC integrates a microcontroller unit, an input voltage acquisition sensor, an output voltage acquisition sensor and an output current acquisition sensor.

[0010] The microcontroller unit can collect the voltage U of the DCDC input terminal through the input terminal voltage collection sensor, the output terminal voltage collection sensor and the output terminal current collection sensor. HV , DCDC output voltage U LV And the DCDC output current I LV , and can also compare these values ​​with preset thresholds, at the DCDC input voltage U HV is greater than the first preset threshold, the DCDC output voltage U LV is lower than the second preset threshold and the DCDC output current I LV After falling below the third preset threshold, the duration is recorded, and it can be determined whether the above preset conditions are met. In addition, the DCDC fault status (for example: high-level fault status: DCDC level 3 fault) and DCDC working status (for example: normal or abnormal) can also be fed back to the vehicle controller.

[0011] Furthermore, it also includes: when the whole vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected. If the DCDC working instruction is not detected, the DCDC stops working; if the DCDC working instruction is detected, the power supply system reports that the DCDC working status is normal, and the DCDC works normally to output low-voltage DC current and voltage to the battery and / or the low-voltage load of the whole vehicle.

[0012] The DCDC working instruction is continuously issued by the vehicle controller when the vehicle is powered on and the DCDC working status is normal. However, when the DCDC working status is abnormal or the DCDC fails, the vehicle controller stops sending the working request enable signal to the power supply system, and the power supply system can no longer detect the DCDC working instruction, so that the DCDC can stop working in time.

[0013] Furthermore, it also includes: when the whole vehicle has the conditions for high voltage and no DCDC fault state is received, the whole vehicle controller continues to send a work request enable signal to the power supply system and the battery controller to power on the whole vehicle.

[0014] Furthermore, it also includes: when the whole vehicle is powered on, the battery controller determines whether a BCU working instruction is detected. If no BCU working instruction is detected, the high-voltage relay of the power battery is disconnected; if a BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system.

[0015] The battery controller BCU controls the closing and opening of the high-voltage relay by outputting corresponding signals through the drive circuit based on whether the BCU working instructions issued by the vehicle controller are detected.

[0016] A vehicle DCDC fault status accurate reporting system in the present invention comprises a power supply system, a battery controller and a vehicle controller; the power supply system comprises a DCDC, and the DCDC is integrated with a microcontroller unit, an input voltage acquisition sensor, an output voltage acquisition sensor and an output current acquisition sensor; The power supply system is configured to: monitor the DCDC input voltage, DCDC output voltage and DCDC output current when the vehicle is powered on and the DCDC working state is normal; if the DCDC input voltage is greater than a first preset threshold, the DCDC output voltage is lower than a second preset threshold and the DCDC output current is lower than a third preset threshold, and the duration is not less than a fourth preset threshold, the power supply system reports a DCDC fault state to the vehicle controller and reports to the vehicle controller that the DCDC working state is abnormal; The vehicle controller is configured to: be able to determine whether the vehicle has the conditions for high voltage; when the vehicle has the conditions for high voltage, continuously send a work request enable signal to the power supply system and the battery controller through the vehicle controller; and stop sending a work request enable signal to the power supply system and the battery controller after receiving a DCDC fault state.

[0017] Furthermore, it also includes a battery and a low-voltage load of the whole vehicle; the power supply system is also configured as follows: when the whole vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected. If no DCDC working instruction is detected, the DCDC stops working; if a DCDC working instruction is detected, the power supply system reports that the DCDC working status is normal, and the DCDC works normally, and outputs low-voltage DC current and voltage to the battery and / or the low-voltage load of the whole vehicle.

[0018] Furthermore, the battery controller is configured as follows: when the vehicle is powered on, the battery controller determines whether a BCU working instruction is detected. If no BCU working instruction is detected, the high-voltage relay of the power battery is disconnected; if a BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system.

[0019] A vehicle in the present invention uses the above-mentioned method for accurately reporting the DCDC fault status of the entire vehicle, or / and uses the above-mentioned system for accurately reporting the DCDC fault status of the entire vehicle.

[0020] The beneficial effect of the present invention is that in order to avoid the damage of the internal DSP chip or other control components of the DCDC, which causes the application MCU chip to be unable to feedback the true value of the DCDC state, the present invention uses the DCDC input terminal voltage U HV is greater than the first preset threshold, the DCDC output voltage U LV is lower than the second preset threshold and the DCDC output current I LV When the voltage drops below the third preset threshold and the duration is not less than the fourth preset threshold, it is determined whether the DCDC working state is normal or abnormal, and whether a high-level fault state occurs can be accurately identified. At the same time, after a high-level fault state occurs, it can promptly stop sending a work request enable signal to the power supply system and the battery controller, so that the DCDC is stopped in time and the high-voltage relay of the power battery is disconnected in time, to prevent frequent requests for high voltage from being applied to the DCDC and the battery due to low-voltage energy replenishment needs of the whole vehicle after the DCDC is damaged, thereby preventing the high-voltage circuit from short-circuiting and burning. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to make the purpose, technical solution and beneficial effects of the present invention clearer, the present invention provides the following drawings for illustration: Figure 1 It is a flow chart of the method for accurately reporting the DCDC fault status of a whole vehicle of the present invention; Figure 2 It is a simplified diagram of the energy and signal control relationship of the vehicle DCDC fault status accurate reporting system of the present invention. DETAILED DESCRIPTION

[0022] The technical solution of the present invention is described in detail below in conjunction with the accompanying drawings and embodiments.

[0023] like Figure 1 As shown, a method for accurately reporting the DCDC fault status of a vehicle in this embodiment specifically includes the following steps: S1. After the vehicle controller (VCU) completes initialization, it determines whether the vehicle has the conditions for high voltage.

[0024] It is an existing technology to determine whether the vehicle is ready to power on. The vehicle controller sends a signal to the battery controller (i.e. BCU), the power supply system (i.e. PDU) and the low-voltage controller (i.e. BDC), informing the vehicle that it is ready to power on.

[0025] Among them, the battery controller can control the closing and opening of the high-voltage relay of the power battery (i.e. HV_BATTERY) based on the detected BCU working instructions and output corresponding signals through the drive circuit. The battery controller can also collect the power battery's power, voltage, temperature and other status information and feed it back to the vehicle controller.

[0026] The power supply system includes DCDC (also known as DC controller, DC-DC converter, etc.), which integrates a microcontroller unit (MCU), input voltage acquisition sensor, output voltage acquisition sensor, and output current acquisition sensor. In addition, the power supply system also includes components such as the on-board charger (OBC).

[0027] Among them, the low-voltage controller can collect the battery (ie LV_BATTERY) status information such as power, voltage, temperature, etc. and feed it back to the vehicle controller.

[0028] After receiving the command, the battery controller, power supply system and low-voltage controller will feedback the current status information of the power battery and storage battery (such as voltage, temperature, power, etc.), the working status of the on-board charger OBC, the working status of DCDC, etc. to the vehicle controller. The vehicle controller will make comprehensive judgments and decisions to determine whether the conditions for high voltage are met.

[0029] S101. If the vehicle controller determines that the vehicle does not have the conditions for high voltage, the vehicle controller stops sending work request enable signals to the power supply system and the battery controller to power off the vehicle.

[0030] S102: If the vehicle controller determines that the vehicle is capable of being powered on, the vehicle controller continuously sends a work request enable signal to the power supply system and the battery controller to power on the vehicle; then steps S2 and S4 are performed.

[0031] The continuously sending of the work request enable signal to the power supply system and the battery controller includes at least a DCDC work instruction and a BCU work instruction.

[0032] S2. When the vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected.

[0033] S201: If no DCDC working instruction is detected, the DCDC stops working.

[0034] S202, if the DCDC working instruction is detected, the power supply system reports that the DCDC working state is normal (normal means BUCK), and the DCDC works normally, outputting low-voltage DC current and voltage to the battery and / or the low-voltage load of the vehicle; then proceeding to step S3.

[0035] S3. When the vehicle is powered on and the DCDC is in normal working state, the power supply system monitors the DCDC input voltage, the DCDC output voltage and the DCDC output current; If the DCDC input voltage, DCDC output voltage and DCDC output current meet the preset conditions, the power supply system reports the DCDC fault status to the vehicle controller. At this time, the reported DCDC fault status is a high-level fault status, such as reporting a DCDC level 3 fault, and the power supply system reports the DCDC working status to the vehicle controller as abnormal (abnormal means Failure). After the vehicle controller receives the signal of the DCDC level 3 fault, the vehicle controller stops sending the work request enable signal to the power supply system and the battery controller to power off the vehicle.

[0036] If the DCDC input voltage, the DCDC output voltage and the DCDC output current do not meet the preset conditions, the power supply system reports that the DCDC working state is normal (normal means BUCK), and the DCDC works normally, outputting low-voltage DC current and voltage to the battery and / or the low-voltage load of the vehicle; then the next step S202 is cycled.

[0037] The above pre-conditions are: DCDC input voltage U HV is greater than the first preset threshold, the DCDC output voltage U LV is lower than the second preset threshold and the DCDC output current I LV is lower than the third preset threshold, and the duration is not lower than the fourth preset threshold.

[0038] The first preset threshold, the second preset threshold, the third preset threshold and the fourth preset threshold can all be calibration values. For example, the preset condition is: DCDC input voltage U HV is greater than the first preset threshold value 250V, the DCDC output voltage U LV is lower than the second preset threshold 13V and the DCDC output current I LV It is lower than the third preset threshold value of 2A, and the duration is not lower than the fourth preset threshold value of 1min.

[0039] S4: When the vehicle is powered on, the battery controller determines whether a BCU working instruction is detected.

[0040] S401: If no BCU working instruction is detected, disconnect the high-voltage relay of the power battery.

[0041] S402: If a BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system. In addition, the battery controller can also perform self-test after closing the high-voltage relay of the power battery. If the battery controller detects a fault, the high-voltage relay of the power battery is disconnected in time.

[0042] The whole vehicle will apply high voltage in both OFF and ON gears to ensure that DCDC has input energy to power the whole vehicle at low voltage. However, because DCDC and OBC are integrated together to form a power supply system, if the internal detection circuit and auxiliary power supply device of DCDC are damaged, DCDC will not be able to report its correct status, causing the whole vehicle system to continuously request work instructions and continuously apply high voltage, causing the high-voltage circuit to burn and catch fire. And because the output end of DCDC is connected to the battery, the voltage at the output end of DCDC reflects the larger of the DCDC output value and the battery voltage value, while the current at the output end of DCDC changes according to the low-voltage load (the load can be 0). In order to prevent the internal DSP chip or other control components of DCDC from being damaged, resulting in the inability of the application MCU chip to feedback the true value of the DCDC status, the DCDC input voltage U HV is greater than the first preset threshold, the DCDC output voltage U LV is lower than the second preset threshold and the DCDC output current I LV When the voltage drops below the third preset threshold and the duration is not less than the fourth preset threshold, it is determined whether the DCDC working state is normal or abnormal, and whether a high-level fault state occurs can be accurately identified. At the same time, after a high-level fault state occurs, it can promptly stop sending a work request enable signal to the power supply system and the battery controller, so that the DCDC is stopped in time and the high-voltage relay of the power battery is disconnected in time, to prevent frequent requests for high voltage from being applied to the DCDC and the battery due to low-voltage energy replenishment needs of the whole vehicle after the DCDC is damaged, thereby preventing the high-voltage circuit from short-circuiting and burning.

[0043] like Figure 2 As shown, a vehicle DCDC fault status accurate reporting system in this embodiment includes a power supply system, a battery controller and a vehicle controller; the power supply system includes a DCDC, and the DCDC integrates a microcontroller unit, an input voltage acquisition sensor, an output voltage acquisition sensor and an output current acquisition sensor; The power supply system is configured to: monitor the DCDC input voltage, the DCDC output voltage and the DCDC output current when the vehicle is powered on and the DCDC working state is normal; if the DCDC input voltage is greater than a first preset threshold, the DCDC output voltage is lower than a second preset threshold and the DCDC output current is lower than a third preset threshold, and the duration is not less than a fourth preset threshold, the power supply system reports the DCDC fault state to the vehicle controller; The vehicle controller is configured to: be able to determine whether the vehicle has the conditions for high voltage, continuously send work request enable signals to the power supply system and the battery controller when the vehicle has the conditions for high voltage, and stop sending work request enable signals to the power supply system and the battery controller after receiving a DCDC fault state.

[0044] In this embodiment, it also includes a battery and a low-voltage load of the whole vehicle; the power supply system is also configured as follows: when the whole vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected. If the DCDC working instruction is not detected, the DCDC stops working; if the DCDC working instruction is detected, the power supply system reports that the DCDC working status is normal, and the DCDC works normally, outputting low-voltage DC current and voltage to the battery and / or the low-voltage load of the whole vehicle.

[0045] In this embodiment, the battery controller is configured as follows: when the vehicle is powered on, the battery controller determines whether the BCU working instruction is detected. If the BCU working instruction is not detected, the high-voltage relay of the power battery is disconnected. If the BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system.

[0046] A vehicle in this embodiment uses the above-mentioned method for accurately reporting the DCDC fault status of the entire vehicle, or / and uses the above-mentioned system for accurately reporting the DCDC fault status of the entire vehicle.

[0047] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution of the present invention, which should be included in the scope of the claims of the present invention.

Claims

1. A method for accurately reporting the DCDC fault status of a vehicle, characterized in that: include: When the vehicle is powered on and the DCDC is working normally, monitor the DCDC input voltage, DCDC output voltage and DCDC output current; If the DCDC input voltage, the DCDC output voltage and the DCDC output current meet preset conditions, the power supply system reports the DCDC fault status to the vehicle controller, so that the vehicle controller stops sending a work request enable signal to the power supply system and the vehicle is powered off.

2. The method for accurately reporting vehicle DCDC fault status according to claim 1 is characterized in that: The preset conditions are: the DCDC input voltage is greater than a first preset threshold, the DCDC output voltage is lower than a second preset threshold, and the DCDC output current is lower than a third preset threshold, and the duration is not less than a fourth preset threshold.

3. The method for accurately reporting the DCDC fault status of a vehicle according to claim 1 is characterized in that: The monitoring of the DCDC input voltage, the DCDC output voltage and the DCDC output current is performed by the power supply system, which includes a DCDC, and the DCDC integrates a microcontroller unit, an input voltage acquisition sensor, an output voltage acquisition sensor and an output current acquisition sensor.

4. The method for accurately reporting vehicle DCDC fault status according to claim 3 is characterized in that: Also includes: When the vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected. If no DCDC working instruction is detected, the DCDC stops working. If a DCDC working instruction is detected, the power supply system reports that the DCDC working status is normal, and the DCDC works normally to output low-voltage DC current and voltage to the battery and / or the low-voltage load of the vehicle.

5. The method for accurately reporting vehicle DCDC fault status according to claim 1 is characterized in that: Also includes: When the vehicle is in high-voltage condition and no DCDC fault status is received, the vehicle controller continues to send a work request enable signal to the power supply system and the battery controller to power on the vehicle.

6. The method for accurately reporting vehicle DCDC fault status according to claim 5 is characterized in that: Also includes: When the vehicle is powered on, the battery controller determines whether the BCU working instruction is detected. If the BCU working instruction is not detected, the high-voltage relay of the power battery is disconnected. If the BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system.

7. A vehicle DCDC fault status accurate reporting system, characterized by: Including power supply system, battery controller and vehicle controller; The power supply system includes a DCDC, wherein the DCDC integrates a microcontroller unit, an input voltage acquisition sensor, an output voltage acquisition sensor, and an output current acquisition sensor; The power supply system is configured to: monitor the DCDC input voltage, DCDC output voltage and DCDC output current when the vehicle is powered on and the DCDC working state is normal; if the DCDC input voltage is greater than a first preset threshold, the DCDC output voltage is lower than a second preset threshold and the DCDC output current is lower than a third preset threshold, and the duration is not less than a fourth preset threshold, the power supply system reports a DCDC fault state to the vehicle controller and reports to the vehicle controller that the DCDC working state is abnormal; The vehicle controller is configured to: be able to determine whether the vehicle has the conditions for high voltage; when the vehicle has the conditions for high voltage, continuously send a work request enable signal to the power supply system and the battery controller through the vehicle controller; and stop sending a work request enable signal to the power supply system and the battery controller after receiving a DCDC fault state.

8. The vehicle DCDC fault status accurate reporting system according to claim 7 is characterized by: It also includes batteries and low-voltage loads of the vehicle; The power supply system is also configured as follows: when the vehicle is powered on, the power supply system determines whether a DCDC working instruction is detected. If no DCDC working instruction is detected, the DCDC stops working. If a DCDC working instruction is detected, the power supply system reports that the DCDC working status is normal, and the DCDC works normally, outputting low-voltage DC current and voltage to the battery and / or the low-voltage load of the vehicle.

9. The vehicle DCDC fault status accurate reporting system according to claim 8 is characterized by: The battery controller is configured as follows: when the vehicle is powered on, the battery controller determines whether a BCU working instruction is detected. If no BCU working instruction is detected, the high-voltage relay of the power battery is disconnected. If a BCU working instruction is detected, the high-voltage relay of the power battery is closed to output high-voltage DC current and voltage to the power supply system.

10. A vehicle, characterized in that: The method for accurately reporting the DCDC fault status of the whole vehicle as described in any one of claims 1-6 is used, or / and the system for accurately reporting the DCDC fault status of the whole vehicle as described in any one of claims 7-9 is used.

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