Vehicle high-voltage power-off method, device and equipment and readable storage medium

Abstract

The invention discloses a vehicle high-voltage power-off method, device and equipment and a readable storage medium, and the vehicle high-voltage power-off method comprises the steps: when a vehicle is subjected to high-voltage power-off, if it is detected that a driving motor has a fault and the current rotating speed of the driving motor is greater than a first preset rotating speed, switching the driving motor into a rotating speed control mode, controlling the driving motor by taking the second preset rotating speed as the target rotating speed of the driving motor so as to reduce the rotating speed of the driving motor; when the rotating speed of the driving motor is reduced to a third preset rotating speed, requesting to close an insulated gate bipolar transistor of the driving motor so as to cut off a power supply loop of the driving motor; and when the rotating speed of the driving motor is reduced to a fourth preset rotating speed and the stator current of the driving motor is smaller than the preset safety current, controlling a high-voltage contactor of the driving motor to be switched off, and controlling the driving motor to perform active discharging so as to complete high-voltage power-off. According to the invention, the high-voltage power-off speed of the vehicle is greatly improved through active shutdown intervention.

Description

Technical Field

[0001] This application relates to the field of vehicle safety technology, and in particular to a method, apparatus, device, and readable storage medium for energizing a vehicle under high voltage. Background Technology

[0002] The high-voltage power-off procedure ensures that electric vehicles can safely and orderly disconnect the high-voltage power supply when they are no longer in use or when a malfunction occurs, protecting passengers, maintenance personnel, and the vehicle itself. This process is typically led by the vehicle's overall controller and is completed in coordination with other high-voltage components, such as the battery management system and motor controller.

[0003] Under normal circumstances, the vehicle consumes less electricity under high voltage, has a high level of safety, and can meet the user's requirements.

[0004] However, in some cases, the vehicle's high voltage is de-energized for too long, posing a safety hazard and failing to meet the user's vehicle usage requirements. Summary of the Invention

[0005] This application provides a method, apparatus, device, and readable storage medium for powering off a vehicle at high voltage, aiming to solve the technical problem that in some cases, the power-off time of a vehicle at high voltage is too long, resulting in safety hazards and failing to meet the user's vehicle usage requirements.

[0006] In a first aspect, embodiments of this application provide a method for powering off a vehicle at high voltage, the method comprising: When the vehicle is powered down, if a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed, the drive motor will be switched to speed control mode and the drive motor will be controlled with the second preset speed as the target speed to reduce the speed of the drive motor. When the speed of the drive motor decreases to the third preset speed, it is requested to turn off the insulated gate bipolar transistor of the drive motor in order to cut off the power supply circuit of the drive motor. When the speed of the drive motor decreases to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, the high-voltage contactor of the drive motor is disconnected, and the drive motor is controlled to actively discharge in order to complete the high-voltage power-off.

[0007] Optionally, before switching the drive motor to speed control mode and controlling the drive motor with a second preset speed as the target speed to reduce the drive motor speed when the vehicle is powered down at high voltage, the following steps are included: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, then the vehicle will be powered off.

[0008] Optionally, detecting a fault in the drive motor includes: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference, then it is determined that the drive motor has a control failure fault. If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference, then it is determined that the drive motor has a non-stop fault. If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has an overspeed fault. If the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

[0009] Optionally, before controlling the vehicle to cut off high voltage if the vehicle's current speed is less than a preset safe energizing speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, the following steps are included: Obtain the first vehicle speed calculated and output by the vehicle's electronic braking system and the second vehicle speed calculated and output by the instrument panel; If the first vehicle speed is not an invalid value, and the absolute value of the difference between the first vehicle speed and the second vehicle speed is less than the preset error speed, then the first vehicle speed will be used as the current vehicle speed. If the first vehicle speed is invalid, or if the absolute value of the difference between the first and second vehicle speeds is not less than the preset error speed, then the third vehicle speed is calculated based on the vehicle's gearbox output shaft speed, the overall gear ratio of the transmission system, and the wheel rolling radius, and the third vehicle speed is used as the vehicle's current speed.

[0010] Optionally, before controlling the vehicle to cut off high voltage if the vehicle's current speed is less than a preset safe energizing speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, the following steps are included: When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is not less than the preset safe braking speed, the vehicle's gear will be switched to the last valid gear. When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is less than the preset safe braking speed, or if the vehicle is currently parked, the vehicle's gear will be switched to neutral.

[0011] Secondly, embodiments of this application provide a vehicle high-voltage power-off device, the vehicle high-voltage power-off device comprising: The speed reduction module is used to switch the drive motor to speed control mode when a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed when the vehicle is powered down by high voltage. The drive motor is controlled with the second preset speed as the target speed to reduce the speed of the drive motor. The request module is used to request the insulated gate bipolar transistor of the drive motor to be turned off when the speed of the drive motor decreases to a third preset speed, so as to cut off the power supply circuit of the drive motor. The disconnect module is used to control the high-voltage contactor of the drive motor to disconnect and control the drive motor to actively discharge when the speed of the drive motor drops to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, so as to complete the high-voltage power-off.

[0012] Optionally, the vehicle high-voltage power-off device further includes a power-off module for: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, then the vehicle will be powered off.

[0013] Optionally, detecting a fault in the drive motor is used for: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference, then it is determined that the drive motor has a control failure fault. If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference, then it is determined that the drive motor has a non-stop fault. If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has an overspeed fault. If the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

[0014] Thirdly, embodiments of this application provide a vehicle high-voltage power-off device, which includes a processor, a memory, and a vehicle high-voltage power-off program stored in the memory and executable by the processor. When the vehicle high-voltage power-off program is executed by the processor, it implements the steps of the vehicle high-voltage power-off method as described above.

[0015] Fourthly, embodiments of this application provide a readable storage medium storing a vehicle high-voltage power-down program, wherein when the vehicle high-voltage power-down program is executed by a processor, it implements the steps of the vehicle high-voltage power-down method as described above.

[0016] The beneficial effects of the technical solutions provided in this application include: In this embodiment, when the vehicle is undergoing high-voltage power-off, if a fault is detected in the drive motor and the current speed of the drive motor is greater than a first preset speed, the drive motor is switched to speed control mode, and the drive motor is controlled with a second preset speed as the target speed to reduce the speed of the drive motor; when the speed of the drive motor decreases to a third preset speed, the insulated gate bipolar transistor of the drive motor is requested to be turned off to cut off the power supply circuit of the drive motor; when the speed of the drive motor decreases to a fourth preset speed and the stator current of the drive motor is less than a preset safe current, the high-voltage contactor of the drive motor is controlled to disconnect, and the drive motor is controlled to actively discharge to complete the high-voltage power-off. In this embodiment, when the vehicle is undergoing high-voltage power-down, if the drive motor malfunctions, it may fail to automatically shut down, resulting in a continuous large current in the high-voltage circuit. To ensure safety, the vehicle controller will wait until the drive motor current drops to a safe level before proceeding with the subsequent high-voltage power-down process. This can lead to an excessively long high-voltage power-down time. To avoid unnecessary active intervention, an additional condition is added: if the current speed of the drive motor is too high, the drive motor is actively shut down. This is achieved by switching the drive motor to a precise speed control mode and rapidly reducing its speed to a target speed, such as 0 rpm. When the drive motor speed drops to a lower third preset speed, the insulated gate bipolar transistor of the drive motor is turned off, cutting off the power supply circuit of the drive motor. This proactive shutdown intervention in the event of a drive motor fault greatly improves the speed of high-voltage power-off of the vehicle, avoiding safety hazards caused by excessively long high-voltage power-off time and failing to meet user requirements. In addition, the proactive shutdown intervention of the drive motor is equivalent to actively unloading the drive motor, avoiding the damage to the drive motor that may be caused by rapidly cutting off the high voltage while the drive motor is under load. This achieves fast and safe high-voltage power-off of the vehicle. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the first process of an embodiment of the vehicle high-voltage power-off method of this application; Figure 2 This is a second flowchart illustrating an embodiment of the vehicle high-voltage power-off method of this application; Figure 3 This is a schematic diagram of the third process of an embodiment of the vehicle high-voltage power-off method of this application; Figure 4 This is a functional module diagram of an embodiment of the vehicle high-voltage power-off device of this application; Figure 5 This is a schematic diagram of the hardware structure of the vehicle high-voltage electrical equipment involved in the embodiments of this application. Detailed Implementation

[0018] To enable those skilled in the art to better understand the present application, the technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present application, and not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present application.

[0019] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0020] In a first aspect, embodiments of this application provide a method for powering off a vehicle at high voltage.

[0021] In one embodiment, reference is made to Figure 1 , Figure 1 This is a schematic diagram of the first process of an embodiment of the vehicle high-voltage power-off method of this application, as shown below. Figure 1 As shown, the methods for powering off a vehicle's high voltage include: Step S10: When the vehicle is powered down by high voltage, if a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed, the drive motor is switched to speed control mode and the drive motor is controlled with the second preset speed as the target speed to reduce the speed of the drive motor.

[0022] In this embodiment, when the vehicle is undergoing high-voltage power-down, if the drive motor has a fault (such as control failure, failure to stop, resolver failure, or speed over-limit fault), the drive motor may not be able to stop automatically, resulting in a continuous large current in the high-voltage circuit. To ensure safety, the vehicle controller will wait until the current of the drive motor drops to a safe value before proceeding with the subsequent high-voltage power-down process, which may lead to an excessively long high-voltage power-down time. To avoid unnecessary active intervention, an additional judgment is made that the current speed of the drive motor is greater than a first preset speed, such as 6000 rpm. If the current speed of the drive motor is greater than the first preset speed, it indicates that the current speed of the drive motor is too high, and active intervention to stop the drive motor is required. Specifically, by switching the drive motor's control mode (e.g., the original torque control mode) to a precise speed control mode, and rapidly reducing the drive motor's speed with a second preset speed such as 0 rpm as the target speed, the motor controller adjusts the inverter's output current to make the motor's actual speed converge rapidly towards the target speed such as 0 rpm with maximum acceleration. This can quickly reduce the motor speed from 6000 rpm to below 5500 rpm. The speed control mode directly uses the target speed as the control target, rather than relying on torque commands, which can force the motor to stop quickly, avoiding the waiting time of excessive natural deceleration, shortening the high-voltage power-off time, significantly improving the user experience, and eliminating the risk of "load cut-off" by actively controlling the motor to stop at a safe speed, thus avoiding damage to the drive motor.

[0023] Step S20: When the speed of the drive motor decreases to the third preset speed, request to turn off the insulated gate bipolar transistor of the drive motor to cut off the power supply circuit of the drive motor.

[0024] In this embodiment, when the actual speed of the drive motor drops below a third preset speed, such as 5500 rpm, the vehicle controller sends an IGBT (Insulated Gate Bipolar Transistor) shutdown request command to the drive motor controller. Upon receiving the command, the drive motor controller immediately shuts down the IGBT module, cutting off the power supply circuit to the drive motor. This operation is achieved by gradually attenuating the current (rather than abruptly), causing the stator current of the drive motor to decrease from a high current to a preset safe current, such as 5A, within a short time. The IGBT shutdown is a necessary preliminary step for safe power disconnection. Its function is to rapidly reduce the current to the preset safe current, such as 5A, creating conditions for the high-voltage contactor to disconnect. If this step is skipped and the high-voltage contactor is disconnected directly, the motor will be disconnected under high current conditions, thus triggering a "load-bearing disconnection" fault.

[0025] Step S30: When the speed of the drive motor decreases to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, the high-voltage contactor of the drive motor is controlled to disconnect, and the drive motor is controlled to actively discharge in order to complete the high-voltage power-off.

[0026] In this embodiment, when the actual speed of the drive motor decreases to a fourth preset speed, such as 100 rpm, and the stator current of the drive motor is less than a preset safe current, such as 5A, the high-voltage contactor of the drive motor is disconnected. Disconnecting the high-voltage contactor is the final safe power-off action. At this time, the mechanical contacts of the high-voltage contactor separate, cutting off the high-voltage circuit between the power battery and the drive motor. Subsequently, the drive motor is controlled to actively discharge. Through the active discharge circuit of the drive motor controller (such as a braking resistor or a DC-DC converter), the DC bus voltage of the drive motor is rapidly attenuated to below 60V. The system monitors the bus voltage in real time. When the bus voltage is less than 60V, the vehicle controller automatically shuts off the discharge circuit and enters a low-voltage sleep mode, completing the high-voltage power-off process. After the bus voltage is less than 60V, there is no residual energy in the high-voltage system, better ensuring the safety of maintenance personnel. A bus voltage less than 60V is also a mandatory requirement of the ISO 26262 functional safety standard, ensuring compliance. Based on the above process of reducing the speed of the drive motor, it is easy to understand that the first preset speed, such as 6000 rpm, is greater than the third preset speed, such as 5500 rpm; the third preset speed, such as 5500 rpm, is greater than the fourth preset speed, such as 100 rpm; and the fourth preset speed, such as 100 rpm, is greater than the second preset speed, such as 0 rpm.

[0027] In this embodiment, when the vehicle is undergoing high-voltage power-off, if the drive motor malfunctions (such as control failure, failure to stop, resolver failure, or speed over-limit failure), the drive motor may fail to stop automatically. To avoid unnecessary active intervention, it is additionally determined that the current speed of the drive motor is greater than a first preset speed, such as 6000 rpm. The speed control mode directly uses the target speed as the control objective, rather than relying on torque commands, to force the motor to stop quickly, avoiding excessively long waiting time for natural deceleration. This shortens the high-voltage power-off time, significantly improving the user experience. Furthermore, by actively controlling the motor to stop at a safe speed, the risk of "load cut-off" is eliminated, preventing damage to the drive motor. When the actual speed of the drive motor drops below 5500 rpm, the vehicle controller sends an IGBT shutdown request command to the drive motor controller. Upon receiving the instruction, the IGBT module is immediately shut down, cutting off the power supply circuit to the drive motor. IGBT shutdown is a necessary preliminary step for safe power-off, its function being to rapidly reduce the current to a preset safe current, such as 5A (Amperes), creating conditions for the high-voltage contactor to disconnect. When the actual speed of the drive motor decreases to the fourth preset speed, such as 100 rpm (Revolutions per Minute), and the stator current of the drive motor is less than the preset safe current, such as 5A (Amperes), the control executes the high-voltage contactor disconnection instruction for the drive motor. The mechanical contacts of the high-voltage contactor separate, cutting off the high-voltage circuit between the power battery and the drive motor. Through the active discharge circuit of the drive motor controller, the DC bus voltage of the drive motor is rapidly reduced to below 60V (Volts). The system monitors the bus voltage in real time. When the bus voltage is less than 60V (Volts), the vehicle controller automatically shuts down the discharge circuit and enters a low-voltage sleep mode, completing the high-voltage power-off process. With a bus voltage of <60V, there is no residual electrical energy in the high-voltage system, which better ensures the safety of maintenance personnel. A bus voltage of <60V is also a mandatory requirement of the ISO 26262 functional safety standard, ensuring compliance.

[0028] Furthermore, in one embodiment, reference is made to Figure 2 , Figure 2 This is a second flowchart illustrating an embodiment of the vehicle high-voltage power-off method of this application, as shown below. Figure 2 As shown, before step S10, the following steps are included: Step S00: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is off, then control the vehicle to power off.

[0029] In this embodiment, before executing the high-voltage power-off procedure, the system first performs a triple safety check through a safety condition verification module: when the vehicle's current speed is less than the preset safe power-off speed, the current gear is neutral (N), and the ignition key is in the OFF state, i.e., when all three safety conditions are met simultaneously, the system determines that the vehicle meets the safety conditions for high-voltage power-off and triggers the high-voltage power-off procedure. The preset safe power-off speed is, for example, 0-5 km / h. When the vehicle's current speed is less than this preset safe power-off speed, it is considered that performing high-voltage power-off will not pose a safety risk to the vehicle or its occupants.

[0030] Furthermore, in one embodiment, reference is made to Figure 3 , Figure 3 This is a schematic diagram of the third process of an embodiment of the vehicle high-voltage power-off method of this application, as shown below. Figure 3 As shown, the detection of a fault in the drive motor includes: Step S100: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference greater than the first preset duration, then it is determined that the drive motor has a control failure fault. Step S200: If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference greater than the second preset duration, then it is determined that the drive motor has a non-stop fault. Step S300: If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. Step S400: If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has a speed over-limit fault. In step S500, if the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

[0031] In this embodiment, four common faults that may cause the drive motor to fail to stop automatically are detected in sequence. If one or more of the following faults are detected in the drive motor: control failure fault, failure to stop fault, resolver fault, and speed over-limit fault, it is determined that a fault has been detected in the drive motor. Specifically, if the target torque command of the drive motor is detected to be non-zero (e.g., an acceleration request), and the absolute value of the difference between the actual output torque of the drive motor and the target torque is greater than a first preset difference value, such as 50 Nm, and the duration of this state is greater than a first preset duration, such as 200 ms, it indicates that the drive motor controller cannot respond to the command, and the drive motor cannot stop according to the control command. Therefore, it is determined that the drive motor has a control failure fault. The 200 ms duration threshold helps eliminate signal jitter interference, ensuring the accuracy of fault diagnosis. If the target torque command of the drive motor is detected to be zero (e.g., a stop request), and the second preset difference value is 25 Nm, if the actual output torque is greater than 25 Nm or less than -25 Nm, and the duration of this state is greater than a second preset duration, such as 200 ms, it indicates that the drive motor has not stopped according to the command (e.g., a braking system failure). The high-voltage circuit continues to have current, and it is necessary to wait for the current to decrease. Therefore, it is determined that the drive motor has a control failure fault. If the motor fails to stop, identifying the "drive motor not stopped" scenario can avoid the high-voltage power-off delay caused by waiting for natural deceleration. If a short circuit or open circuit is detected in the drive motor's resolver, a resolver fault is directly determined. The resolver is the drive motor's position / speed sensor. This fault will prevent the system from obtaining the drive motor's status (e.g., misjudging the drive motor's speed as 0), leading to the risk of "load cut-off" when the high voltage is applied. Therefore, there is no need to judge the duration of the fault; the fault state can be directly determined, thus achieving rapid fault response. If the actual speed of the drive motor is detected to be greater than the maximum speed of the drive motor, such as 12000 rpm (revolutions per minute), and the maximum speed is the limit speed of the drive motor, and the duration of this state is greater than a third preset duration, such as 100 ms (milliseconds), then a speed over-limit fault is determined. A speed over-limit is a sign that the drive motor cannot decelerate naturally (e.g., a runaway fault). Without intervention, it will take a long time to decelerate.

[0032] Further, in one embodiment, before step S00, the following steps are included: Obtain the first vehicle speed calculated and output by the vehicle's electronic braking system and the second vehicle speed calculated and output by the instrument panel; If the first vehicle speed is not an invalid value, and the absolute value of the difference between the first vehicle speed and the second vehicle speed is less than the preset error speed, then the first vehicle speed will be used as the current vehicle speed. If the first vehicle speed is invalid, or if the absolute value of the difference between the first and second vehicle speeds is not less than the preset error speed, then the third vehicle speed is calculated based on the vehicle's gearbox output shaft speed, the overall gear ratio of the transmission system, and the wheel rolling radius, and the third vehicle speed is used as the vehicle's current speed.

[0033] In this embodiment, the first vehicle speed V1 calculated and output by the electronic braking system and the second vehicle speed V2 calculated and output by the instrument are first obtained. It is then determined whether V1 is an invalid value, where V1 = FF or FE (representing an invalid vehicle speed signal). If the first vehicle speed V1 is valid, and the absolute value of the difference between the first vehicle speed V1 and the second vehicle speed V2, |V1-V2|, is less than the preset error speed, such as 10 km / h, then the first vehicle speed V1 is taken as the current vehicle speed. Otherwise, the current vehicle speed is calculated based on the vehicle's gearbox output shaft speed, the overall gear ratio of the transmission system, and the wheel rolling radius. The calculation formula is, for example, the current vehicle speed V = (n×2πr×3.6) / (i×60), where n is the gearbox output shaft speed in rpm, r is the wheel rolling radius in m, and i is the dimensionless overall gear ratio of the transmission system. The calculated current vehicle speed V is in km / h. Since the current vehicle speed is compared with a preset safe power-off speed, such as 5 km / h, to determine whether the vehicle can perform high-voltage power-off, verifying the accuracy of the current vehicle speed avoids the problem of inaccurate or invalid current speeds potentially causing the high-voltage resistance to break. This ensures that the vehicle can perform high-voltage power-off when the current speed meets the safe power-off speed, and prevents the vehicle from accidentally triggering the high-voltage power-off permission when it is actually in motion, which could cause the moving vehicle to lose power and high-voltage power steering function, endangering personnel safety. This covers scenarios where the vehicle speed signal fails, thus improving the reliability of the system.

[0034] Further, in one embodiment, before step S00, the following steps are included: When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is not less than the preset safe braking speed, the vehicle's gear will be switched to the last valid gear. When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is less than the preset safe braking speed, or if the vehicle is currently parked, the vehicle's gear will be switched to neutral.

[0035] In this embodiment, when the ignition key is detected to be in the OFF state and the current gear signal C>3 (invalid value), the system executes the following logic: if the vehicle's current speed is ≥5km / h, the last valid gear is maintained (to prevent the vehicle from suddenly shifting into N gear and losing power); if the vehicle's current speed is <5km / h or it is in a parked state, it is forcibly switched to N gear (to ensure that the vehicle is in neutral when the high voltage is off, to avoid accidental driving). By verifying the rationality of the vehicle's current gear status, the system avoids situations where the vehicle is actually in motion, and the loss of the gear signal could mistakenly trigger the high voltage to be off, causing the moving vehicle to lose power and high voltage steering assist function, endangering personnel safety. This covers the scenario of gear signal failure and improves the reliability of the system.

[0036] Secondly, embodiments of this application also provide a vehicle high-voltage power-off device.

[0037] In one embodiment, reference is made to Figure 4 , Figure 4 This is a functional module diagram of an embodiment of the vehicle high-voltage power-off device of this application, as shown below. Figure 4 As shown, the vehicle's high-voltage power-off device includes: The speed reduction module 10 is used to switch the drive motor to speed control mode when the vehicle is powered down by high voltage. If a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed, the drive motor is controlled with the second preset speed as the target speed to reduce the speed of the drive motor. The request module 20 is used to request the shutdown of the insulated gate bipolar transistor of the drive motor when the speed of the drive motor decreases to a third preset speed, so as to cut off the power supply circuit of the drive motor. The disconnect module 30 is used to control the high-voltage contactor of the drive motor to disconnect and control the drive motor to actively discharge when the speed of the drive motor drops to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, so as to complete the high-voltage power-off.

[0038] Furthermore, in one embodiment, the vehicle high-voltage power-off device further includes a power-off module for: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, then the vehicle will be powered off.

[0039] Furthermore, in one embodiment, the detection of a fault in the drive motor is used for: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference, then it is determined that the drive motor has a control failure fault. If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference, then it is determined that the drive motor has a non-stop fault. If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has an overspeed fault. If the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

[0040] Furthermore, in one embodiment, the vehicle high-voltage power-off device further includes a vehicle speed verification module, used for: Obtain the first vehicle speed calculated and output by the vehicle's electronic braking system and the second vehicle speed calculated and output by the instrument panel; If the first vehicle speed is not an invalid value, and the absolute value of the difference between the first vehicle speed and the second vehicle speed is less than the preset error speed, then the first vehicle speed will be used as the current vehicle speed. If the first vehicle speed is invalid, or if the absolute value of the difference between the first and second vehicle speeds is not less than the preset error speed, then the third vehicle speed is calculated based on the vehicle's gearbox output shaft speed, the overall gear ratio of the transmission system, and the wheel rolling radius, and the third vehicle speed is used as the vehicle's current speed.

[0041] Furthermore, in one embodiment, the vehicle high-voltage power-off device further includes a gear control module, used for: When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is not less than the preset safe braking speed, the vehicle's gear will be switched to the last valid gear. When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is less than the preset safe braking speed, or if the vehicle is currently parked, the vehicle's gear will be switched to neutral.

[0042] The functions of each module in the above-mentioned vehicle high-voltage power-off device correspond to the steps in the above-mentioned vehicle high-voltage power-off method embodiment, and their functions and implementation processes will not be described in detail here.

[0043] Thirdly, embodiments of this application provide a vehicle high-voltage electrical device.

[0044] Reference Figure 5 , Figure 5This is a schematic diagram of the hardware structure of the vehicle high-voltage electrical equipment involved in the embodiments of this application. In the embodiments of this application, the vehicle high-voltage electrical equipment may include a processor, a memory, a communication interface, and a communication bus.

[0045] The communication bus can be of any type and is used to interconnect the processor, memory, and communication interface.

[0046] Communication interfaces include input / output (I / O) interfaces, physical interfaces, and logical interfaces used for interconnecting devices within the vehicle's high-voltage electrical equipment, as well as interfaces used for interconnecting the vehicle's high-voltage electrical equipment with other devices (such as other computing devices or user equipment). Physical interfaces can be Ethernet interfaces, fiber optic interfaces, ATM interfaces, etc.; user equipment can be displays, keyboards, etc.

[0047] Memory can be various types of storage media, such as random access memory (RAM), read-only memory (ROM), non-volatile RAM (NVRAM), flash memory, optical storage, hard disk, programmable ROM (PROM), erasable PROM (EPROM), electrically erasable PROM (EEPROM), etc.

[0048] The processor can be a general-purpose processor, which can call the vehicle high-voltage power-down program stored in the memory and execute the vehicle high-voltage power-down method provided in the embodiments of this application. For example, the general-purpose processor can be a central processing unit (CPU). The method executed when the vehicle high-voltage power-down program is called can be referred to in the various embodiments of the vehicle high-voltage power-down method of this application, and will not be repeated here.

[0049] Those skilled in the art will understand that Figure 5 The hardware structure shown does not constitute a limitation of this application and may include more or fewer components than shown, or combine certain components, or have different component arrangements.

[0050] Fourthly, embodiments of this application also provide a readable storage medium.

[0051] The present application has a readable storage medium storing a vehicle high-voltage power-down program, wherein when the vehicle high-voltage power-down program is executed by a processor, it implements the steps of the vehicle high-voltage power-down method as described above.

[0052] The method implemented when the vehicle high-voltage power-off procedure is executed can be referred to in various embodiments of the vehicle high-voltage power-off method of this application, and will not be repeated here.

[0053] It should be noted that the sequence numbers of the embodiments in this application are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0054] The terms "comprising" and "having," and any variations thereof, in the specification, claims, and accompanying drawings of this application are intended to cover non-exclusive inclusion. For example, a process, method, system, product, or apparatus that includes a series of steps or units is not limited to the listed steps or units, but may optionally include steps or units not listed, or may optionally include other steps or units inherent to such process, method, product, or apparatus. The terms "first," "second," and "third," etc., are used to distinguish different objects, etc., and do not indicate a sequence, nor do they limit "first," "second," and "third" to different types.

[0055] In the description of the embodiments of this application, terms such as "exemplary," "for example," or "for instance" are used to indicate examples, illustrations, or explanations. Any embodiment or design described as "exemplary," "for example," or "for instance" in the embodiments of this application should not be construed as being more preferred or advantageous than other embodiments or designs. Specifically, the use of terms such as "exemplary," "for example," or "for instance" is intended to present the relevant concepts in a concrete manner.

[0056] In the description of the embodiments of this application, unless otherwise stated, " / " means "or". For example, A / B can mean A or B. The "and / or" in the text is merely a description of the relationship between related objects, indicating that there can be three relationships. For example, A and / or B can mean: A exists alone, A and B exist simultaneously, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more.

[0057] In some processes described in the embodiments of this application, multiple operations or steps are included in a specific order. However, it should be understood that these operations or steps may not be executed in the order they appear in the embodiments of this application, or they may be executed in parallel. The sequence number of the operation is only used to distinguish different operations, and the sequence number itself does not represent any execution order. In addition, these processes may include more or fewer operations, and these operations or steps may be executed sequentially or in parallel, and these operations or steps may be combined.

[0058] Through the above description of the embodiments, those skilled in the art can clearly understand that the methods of the above embodiments can be implemented by means of software plus necessary general-purpose hardware platforms. Of course, they can also be implemented by hardware, but in many cases the former is a better implementation method. Based on this understanding, the technical solution of this application, in essence, or the part that contributes to the prior art, can be embodied in the form of a software product. This computer software product is stored in a storage medium (such as ROM / RAM, magnetic disk, optical disk) as described above, and includes several instructions to cause a terminal device to execute the methods described in the various embodiments of this application.

[0059] The above are merely preferred embodiments of this application and do not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A method for energizing a vehicle with high voltage, characterized in that, The vehicle high-voltage power-off method includes: When the vehicle is powered down, if a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed, the drive motor will be switched to speed control mode and the drive motor will be controlled with the second preset speed as the target speed to reduce the speed of the drive motor. When the speed of the drive motor decreases to the third preset speed, it is requested to turn off the insulated gate bipolar transistor of the drive motor in order to cut off the power supply circuit of the drive motor. When the speed of the drive motor decreases to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, the high-voltage contactor of the drive motor is disconnected, and the drive motor is controlled to actively discharge in order to complete the high-voltage power-off.

2. The vehicle high-voltage power-off method as described in claim 1, characterized in that, Before switching the drive motor to speed control mode and controlling the drive motor to reduce its speed when the vehicle is powered down at high voltage, if a fault is detected in the drive motor and the current speed of the drive motor is greater than a first preset speed, the following steps are included: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, then the vehicle will be powered off.

3. The vehicle high-voltage power-off method as described in claim 1, characterized in that, The detected fault in the drive motor includes: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference, then it is determined that the drive motor has a control failure fault. If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference, then it is determined that the drive motor has a non-stop fault. If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has an overspeed fault. If the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

4. The vehicle high-voltage power-off method as described in claim 2, characterized in that, Before controlling the vehicle to cut off high voltage if the vehicle's current speed is less than the preset safe energizing speed, the vehicle's current gear is neutral, and the ignition key is off, the following steps are taken: Obtain the first vehicle speed calculated and output by the vehicle's electronic braking system and the second vehicle speed calculated and output by the instrument panel; If the first vehicle speed is not an invalid value, and the absolute value of the difference between the first vehicle speed and the second vehicle speed is less than the preset error speed, then the first vehicle speed will be used as the current vehicle speed. If the first vehicle speed is invalid, or if the absolute value of the difference between the first and second vehicle speeds is not less than the preset error speed, then the third vehicle speed is calculated based on the vehicle's gearbox output shaft speed, the overall gear ratio of the transmission system, and the wheel rolling radius, and the third vehicle speed is used as the vehicle's current speed.

5. The vehicle high-voltage power-off method as described in claim 2, characterized in that, Before controlling the vehicle to cut off high voltage if the vehicle's current speed is less than the preset safe energizing speed, the vehicle's current gear is neutral, and the ignition key is off, the following steps are taken: When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is not less than the preset safe braking speed, the vehicle's gear will be switched to the last valid gear. When the vehicle's ignition key is detected to be off and the vehicle's current gear is invalid, if the vehicle's current speed is less than the preset safe braking speed, or if the vehicle is currently parked, the vehicle's gear will be switched to neutral.

6. A vehicle high-voltage power-off device, characterized in that, The vehicle high-voltage power-off device includes: The speed reduction module is used to switch the drive motor to speed control mode when a fault is detected in the drive motor and the current speed of the drive motor is greater than the first preset speed when the vehicle is powered down by high voltage. The drive motor is controlled with the second preset speed as the target speed to reduce the speed of the drive motor. The request module is used to request the insulated gate bipolar transistor of the drive motor to be turned off when the speed of the drive motor decreases to a third preset speed, so as to cut off the power supply circuit of the drive motor. The disconnect module is used to control the high-voltage contactor of the drive motor to disconnect and control the drive motor to actively discharge when the speed of the drive motor drops to the fourth preset speed and the stator current of the drive motor is less than the preset safe current, so as to complete the high-voltage power-off.

7. The vehicle high-voltage power-off device as described in claim 6, characterized in that, The vehicle high-voltage power-off device also includes a power-off module for: If the vehicle's current speed is less than the preset safe power-off speed, the vehicle's current gear is neutral, and the vehicle's ignition key is in the off state, then the vehicle will be powered off.

8. The vehicle high-voltage power-off device as described in claim 6, characterized in that, The detection of a fault in the drive motor is used for: If the target torque of the drive motor is not zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the first preset difference, then it is determined that the drive motor has a control failure fault. If the target torque of the drive motor is zero, and the absolute value of the difference between the current torque and the target torque of the drive motor is greater than the duration of the second preset difference, then it is determined that the drive motor has a non-stop fault. If the resolver of the drive motor is short-circuited, it is determined that the drive motor has a resolver fault. If the duration for which the current speed of the drive motor is greater than the maximum speed of the drive motor is greater than the third preset duration, then it is determined that the drive motor has an overspeed fault. If the drive motor has one or more of the following faults: control failure, failure to stop, resolver failure, and speed over-limit fault, then it is determined that a fault has been detected in the drive motor.

9. A vehicle high-voltage electrical device, characterized in that, The vehicle high-voltage power-off device includes a processor, a memory, and a vehicle high-voltage power-off program stored in the memory and executable by the processor, wherein when the vehicle high-voltage power-off program is executed by the processor, it implements the steps of the vehicle high-voltage power-off method as described in any one of claims 1 to 5.

10. A readable storage medium, characterized in that, The readable storage medium stores a vehicle high-voltage power-down program, wherein when the vehicle high-voltage power-down program is executed by a processor, it implements the steps of the vehicle high-voltage power-down method as described in any one of claims 1 to 5.

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