CN116572936A

CN116572936A - Vehicle control method and vehicle

Info

Publication number: CN116572936A
Application number: CN202310571772.XA
Authority: CN
Inventors: 刘寒; 杨雪静; 张峻
Original assignee: Great Wall Motor Co Ltd
Current assignee: Great Wall Motor Co Ltd
Priority date: 2023-05-19
Filing date: 2023-05-19
Publication date: 2023-08-11

Abstract

The embodiment of the application is suitable for the technical field of vehicles, and provides a vehicle control method and a vehicle, wherein the method comprises the following steps: if the vehicle is in a limp-home mode, switching the power supply equipment in the vehicle to be low-voltage battery equipment; the relay of the high-voltage battery equipment in the vehicle is disconnected under the limp mode, the driving motor in the vehicle stops working, and the power supply equipment comprises a generator; regulating the voltage of the high-voltage battery device to a pre-charge voltage; the switching power supply equipment is high-voltage battery equipment so as to control the vehicle to be switched into a normal mode; in the normal mode, the relay is closed, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle during operation. By adopting the method, when the relay of the high-voltage battery equipment is disconnected, the mode of the vehicle can be controlled to be switched to the normal mode, and the driving scene of the vehicle is improved.

Description

Vehicle control method and vehicle

Technical Field

The application belongs to the technical field of vehicles, and particularly relates to a vehicle control method and a vehicle.

Background

The limp-home mode of the vehicle refers to that when an electric control device (such as a high-voltage battery device) in the vehicle fails, the whole vehicle controller automatically starts a backup control loop to control an engine so that the vehicle can travel briefly or stop for rescue. However, this vehicle control strategy is not perfect.

For example, when the battery temperature of the high-voltage battery device is lower than the operating temperature, the high-voltage battery device may be limited by the battery performance, and the relay of the high-voltage battery device may be disconnected, resulting in the failure of the high-voltage battery device to discharge normally. At this time, the high-voltage equipment (e.g., the driving motor) in the vehicle cannot function normally. Therefore, in order to maintain the running of the vehicle, the vehicle can be driven only by the engine.

Based on this, in the prior art, the control strategy when the vehicle is in the limp mode due to the relay of the high-voltage battery device being disconnected is not reasonable, and the vehicle cannot be restored to the normal mode for running, resulting in limited running of the vehicle.

Disclosure of Invention

The embodiment of the application provides a vehicle control method and a vehicle, which can solve the problem that a control strategy is unreasonable when the vehicle is in a limp mode due to the disconnection of a relay of high-voltage battery equipment.

In a first aspect, an embodiment of the present application provides a vehicle control method, including:

if the vehicle is in a limp-home mode, switching the power supply equipment in the vehicle to be low-voltage battery equipment; the relay of the high-voltage battery equipment in the vehicle is disconnected under the limp mode, the driving motor in the vehicle stops working, and the power supply equipment comprises a generator;

Regulating the voltage of the high-voltage battery device to a pre-charge voltage;

the switching power supply equipment is high-voltage battery equipment so as to control the vehicle to be switched into a normal mode; in the normal mode, the relay is closed, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle during operation.

In a second aspect, an embodiment of the present application provides a vehicle control apparatus including:

the first switching module is used for switching power supply equipment in the vehicle to be low-voltage battery equipment if the vehicle is in a limp-home mode; the relay of the high-voltage battery equipment in the vehicle is disconnected under the limp mode, the driving motor in the vehicle stops working, and the power supply equipment comprises a generator;

the adjusting module is used for adjusting the voltage of the high-voltage battery equipment to the pre-charging voltage;

the first control module is used for switching the power supply equipment to be high-voltage battery equipment so as to control the vehicle to be switched to a normal mode; in the normal mode, the relay is closed, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle during operation.

In a third aspect, an embodiment of the present application provides a vehicle comprising a memory, a processor and a computer program stored in the memory and executable on the processor, the processor implementing a method according to the first aspect as described above when executing the computer program.

In a fourth aspect, embodiments of the present application provide a computer readable storage medium storing a computer program which when executed by a processor performs a method as in the first aspect.

In a fifth aspect, embodiments of the present application provide a computer program product for causing a vehicle to carry out the method of the first aspect described above when the computer program product is run on the vehicle.

Compared with the prior art, the embodiment of the application has the beneficial effects that: when the vehicle is in a limp-home mode due to the disconnection of the relay of the high-voltage battery equipment, the driving motor in the vehicle stops working, and the engine not only needs to drive the vehicle, but also needs to drive the generator to work so as to supply power to electric equipment (such as low-voltage equipment) of the vehicle and maintain the running of the vehicle. At this time, in order to be able to switch the vehicle to the normal mode, the low-voltage device may be temporarily replaced with a low-voltage battery device in the vehicle to supply power to the low-voltage device. And then, after the voltage of the high-voltage battery equipment is regulated to the pre-charging voltage, the relay is closed, so that the short-circuit condition of the high-voltage battery equipment caused by the closing of the relay can be avoided, and the high-voltage battery equipment is protected. And, after the relay is closed, the high-voltage battery device may normally supply power to the low-voltage device as well as the high-voltage device (e.g., driving motor) instead of the low-voltage battery device and the generator. At this time, the generator and the driving motor can normally provide torque, so that the vehicle can run in a driving mode corresponding to the normal mode. When the generator is in a power supply state, the generator cannot be directly switched to a torque output state, so that in the switching process, the low-voltage equipment can be temporarily powered by the low-voltage equipment first, and the generator is controlled to exit the power supply state on the basis of maintaining the running of the vehicle. Then, after the relay is closed, the generator and the drive motor may be switched to a torque output state to provide torque to the vehicle. Based on this, when the relay of the battery device is turned off, the mode of the vehicle can be controlled to be switched to the normal mode, and the driving scene of the vehicle can be improved.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are needed in the embodiments or the description of the prior art will be briefly introduced below, and it is obvious that the drawings in the following description are only some embodiments of the present application, and that other drawings can be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a flow chart illustrating an implementation of a vehicle control method according to an embodiment of the present application;

FIG. 2 is a flow chart illustrating an implementation of a vehicle control method according to another embodiment of the present application;

FIG. 3 is a schematic diagram illustrating the operation of various devices in a vehicle according to a method for controlling a vehicle according to an embodiment of the present application;

fig. 4 is a schematic structural view of a vehicle control device according to an embodiment of the present application;

fig. 5 is a schematic structural diagram of a vehicle according to an embodiment of the present application.

Detailed Description

In the following description, for purposes of explanation and not limitation, specific details are set forth such as the particular system architecture, techniques, etc., in order to provide a thorough understanding of the embodiments of the present application. It will be apparent, however, to one skilled in the art that the present application may be practiced in other embodiments that depart from these specific details. In other instances, detailed descriptions of well-known systems, devices, circuits, and methods are omitted so as not to obscure the description of the present application with unnecessary detail.

It should be understood that the terms "comprises" and/or "comprising," when used in this specification and the appended claims, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof.

Furthermore, the terms "first," "second," "third," and the like in the description of the present specification and in the appended claims, are used for distinguishing between descriptions and not necessarily for indicating or implying a relative importance.

The limp-home mode of the vehicle refers to when an electronic control device (e.g., a high-voltage battery device) in the vehicle fails, the electronic controller automatically enables a backup control loop to control the engine so that the vehicle can travel briefly or stop for rescue. However, this vehicle control strategy is not perfect.

For example, when the battery temperature of the high-voltage battery device is lower than the operating temperature, for example, the battery temperature is lower than-30 °. At this time, the high-voltage battery device will be limited by the reason of battery performance, and the relay is automatically opened, so that the high-voltage battery device cannot be normally discharged.

In this case, with a hybrid vehicle, in order to maintain the vehicle running, the vehicle needs to be driven by the engine, and the high-voltage apparatus needs to be controlled to stop operating. For example, the drive motor and the high-pressure air conditioner in the vehicle are controlled to prohibit operations. Among them, since the drive motor is prohibited from operating, the device that outputs the drive torque for the vehicle is only the engine.

In view of this, in the prior art, the strategy for controlling the vehicle in the limp-home mode due to the off-state of the relay is not reasonable, and the vehicle cannot be returned to the normal mode, resulting in limitation of the vehicle running.

In this embodiment, in order to switch the vehicle back to the normal mode when the vehicle is in the limp-home mode due to the disconnection of the relay of the battery device, the embodiment of the application provides a vehicle control method which can be applied to the vehicle-mounted device. For example, the in-vehicle device may be a vehicle controller (Vehicle Control Unit) and a battery management system (Battery Management System, BMS) in a vehicle, which is not limited thereto.

In this embodiment, the in-vehicle power supply device includes a generator, a high-voltage battery device, and a low-voltage battery device. However, in the normal mode of the vehicle, the generator is used to provide torque, and the high-voltage battery device is used to power the various consumers (high-voltage device and low-voltage device) in the vehicle, and the low-voltage battery device cannot store a large amount of electricity because of its limited battery performance. Therefore, the low-voltage battery device cannot supply power to the high-voltage device and the low-voltage device for a long time. Thus, in practical applications, the low voltage battery device is only used to power the low voltage device.

Based on this, the high-voltage battery device stops the power supply when the vehicle is in the limp mode, and can be supplied with power only by the generator or the low-voltage battery device. And, because the low-voltage battery device cannot be powered for a long time, the generator is typically powered by the engine in a limp-home mode. However, when the generator is powered, if the high voltage device (driving motor) is powered, the energy consumption of the generator is increased, so that the output power of the generator is greater than the maximum output power of the generator, and overdischarge is caused to the generator. Thus, in limp-home mode, the generator typically only powers the low voltage devices, such that the vehicle cannot resume normal mode.

Referring to fig. 1, fig. 1 shows a flowchart of an implementation of a vehicle control method according to an embodiment of the present application, where the method includes the following steps:

s101, if the vehicle is in a limp mode, switching power supply equipment in the vehicle to be low-voltage battery equipment; in a limp-home mode, a relay of a high-voltage battery device in the vehicle is disconnected, a driving motor in the vehicle stops working, and a power supply device comprises a generator.

In an embodiment, the high-voltage battery device may be a battery pack formed by a plurality of single batteries, or may be a 48V battery, which is not limited thereto. The high-voltage battery device is used for supplying power to each high-voltage device in the vehicle, and the battery voltage output by the high-voltage battery device can be converted into a voltage with a lower amplitude through a direct current-direct current (Direct Current Direct Current, DCDC) converter so as to supply power to the low-voltage device. For example, the battery voltage output by a high voltage battery device is typically 48V, while the operating voltage required by a low voltage device is typically 12V.

In an embodiment, the high voltage devices include, but are not limited to, DCDC converters, driving motors, high voltage air conditioners, and the like, which will not be described in detail. It will be appreciated that after the relay of the high voltage battery device is opened, the high voltage battery device cannot normally supply power, and therefore, the high voltage device will stop working. That is, the driving motor is stopped in a standby state. At this time, the vehicle will be driven by the engine only, and the vehicle cannot resume running in the normal mode.

It should be noted that, in the limp-home mode, the electric equipment in the vehicle needs to be ensured to work normally when the vehicle runs, and at this time, the engine also needs to drive the generator to rotate so that the generator can supply power. That is, the power supply device includes a generator.

It is added that when the consumer comprises low voltage equipment, the voltage generated by the generator is typically greater than 12V. Therefore, the power supply apparatus also typically includes the DCDC converter to convert the voltage generated by the generator.

In an embodiment, the low-voltage battery device may be a 12V battery, or other battery pack that may provide a 12V voltage, which is not limited thereto.

When the vehicle is switched from the limp-home mode to the normal mode, the high-voltage battery device is required to operate normally, and power supply by the generator is not required. However, in order to ensure normal power supply to the electric equipment of the vehicle, if the power supply of the generator is stopped after the relay of the high-voltage battery equipment is closed, the voltage of the power supply of the electric equipment by the generator is lower than the battery voltage generated when the high-voltage battery equipment works. At this point, the high voltage battery device will provide a high voltage to the generator when in operation. However, when the high voltage provided is greater than the voltage at the working output of the generator, the generator will enter a pressure relief state, which is prone to cause generator failure. For example, the rotor in a generator may need to run at high speed to consume the high voltage provided by the high voltage battery device. However, high speed operation may cause rotor failure, reducing driving safety.

And if the generator is controlled to stop working firstly and then the relay is controlled to be closed, the electric equipment in the vehicle cannot work normally in the period from the stop of the working of the generator to the closing of the relay. At this time, the vehicle will be in a powered-down state and stop traveling. That is, the mode can be realized only by the user stopping at the side and powering down the vehicle, so that the user experience is reduced, and the vehicle automation cannot be realized.

Based on this, in order to be able to automatically switch the vehicle from the limp-home mode to the normal mode, no user is required to stop the vehicle at his side, and the vehicle-mounted device may switch the power supply device in the vehicle to the low-voltage battery device. That is, the generator may stop supplying power and be supplied by the low-voltage battery device during the above-described mode switching. At this time, the generator does not need to supply power, and the generator state thereof may be a standby state.

It should be noted that, due to its battery performance, for example, when the battery temperature of the high-voltage battery device is lower than a preset temperature (-30 ℃ or-10 ℃), the relay will be turned off, so that the vehicle runs in the limp-home mode.

Based on this, when the vehicle is in the limp-home mode, the battery temperature is also controlled to be greater than the preset temperature, so that the vehicle control method described above may be executed.

Specifically, the vehicle-mounted device may acquire a battery temperature in the battery device, and then, when the battery temperature is lower than or equal to a preset temperature, heat the high-voltage battery device based on waste heat generated by an engine operation when the vehicle is traveling in a limp mode until the battery temperature is higher than the preset temperature.

When the battery temperature is higher than the preset temperature, the high-voltage battery equipment can be considered to meet the precondition that the relay is closed. Thus, the relay can be controlled to close. I.e., the above-described vehicle control method is performed.

In one embodiment, based on the above description, the vehicle is powered solely by the engine in the limp-home mode. Therefore, in order to implement the vehicle control method, when the battery temperature is determined to be lower than or equal to the preset temperature, the vehicle-mounted device may heat the high-voltage battery device by using waste heat generated by the engine operation, until the battery temperature is detected to be higher than the preset temperature, and then switch the power supply device in the vehicle to be the low-voltage battery device. Otherwise, the vehicle still needs to travel in a limp-home mode. The manner of obtaining the battery temperature is described above, and will not be explained.

In an embodiment, the battery temperature may be determined according to the BMS system, which will not be described in detail.

It should be specifically noted that, because the power supply device in the vehicle is switched to be the low-voltage battery device, the vehicle-mounted device needs to determine whether the battery information of the low-voltage battery device meets the preset power supply condition in advance, so that the low-voltage battery device can normally supply power in the following S102-S103 executing process, thereby avoiding sudden power failure and parking of the vehicle and ensuring driving safety.

For example, the vehicle-mounted device may acquire battery information of the low-voltage battery device, and then, when determining that the low-voltage battery device meets a preset power supply condition according to the battery information, switch the power supply device in the vehicle to be the low-voltage battery device. Otherwise, when the battery equipment is determined to not meet the preset power supply condition according to the battery information, the vehicle is still controlled to maintain the limp mode to run.

Specifically, the vehicle-mounted device may acquire the remaining power and the battery voltage of the battery device. And then, when the residual electric quantity is larger than the preset electric quantity and the battery voltage is larger than the working voltage of the low-voltage equipment in the vehicle during working, determining that the low-voltage equipment meets the preset power supply condition. Further, the power supply device in the vehicle is switched to a low-voltage battery device. Otherwise, when the remaining power is smaller than or equal to the preset power and/or the battery voltage is smaller than or equal to the working voltage of the low-voltage equipment in the vehicle during working, determining that the low-voltage equipment does not meet the preset power supply condition. Further, the vehicle is still controlled to travel in the limp-home mode.

In which the battery voltage of the low-voltage battery device is generally related to the operation performance of the low-voltage battery device itself, and thus the above-described operation voltage can be determined directly based on the device information of the low-voltage battery device.

Specifically, for the battery voltage, the in-vehicle device may acquire the battery temperature and the remaining power of the battery device. And then, determining the battery voltage of the low-voltage battery equipment under the battery temperature and the residual electric quantity according to the preset working performance of the low-voltage battery equipment.

The battery temperature and the residual electric quantity of the low-voltage battery equipment can be determined according to a battery management system. The preset working performance is a property parameter of the battery, and the property parameter is determined when the battery leaves a factory.

Specifically, the preset working performance can be used for representing specific parameters such as rated capacity, working voltage, charge-discharge multiplying power, maximum charging power, impedance, self-discharge rate and the like of the battery equipment under different battery temperatures and residual electric quantities.

In an embodiment, the preset power may be set according to practical situations, and for example, the preset power may be 75% of the rated power of the battery device. And, the operating voltage at which each low-voltage device in the vehicle operates is generally a fixed voltage, and specifically, the operating voltage may be 12V.

It should be noted that, when steps S101-S102 are performed, power is supplied from the battery device. Therefore, the residual electric quantity is required to be larger than the preset electric quantity so as to ensure that the battery equipment can normally supply power, avoid the sudden power failure and parking of the vehicle and ensure the driving safety.

And, the purpose of requiring the battery voltage to be greater than the operating voltage at which the low-voltage equipment in the vehicle operates is to: the battery voltage output by the low-voltage battery device is not stable due to vibration or change of the battery temperature of the low-voltage battery device in the running process of the vehicle. At this time, the battery voltage output by the low-voltage battery device may be far lower than the operating voltage of the low-voltage device, resulting in an under-voltage of the low-voltage battery device, and thus, the power supply to the low-voltage device is stopped. Based on this, it is necessary to determine that the battery voltage is greater than the operating voltage of the low voltage device to ensure driving safety.

In particular, since the in-vehicle device can control the high-voltage device in the vehicle to stop operating (for example, can be in a standby state), it is only necessary to consider the operating voltage of the low-voltage device when executing steps S101 to S103. Therefore, the battery equipment can supply power for a long time, and the battery voltage output by the battery equipment cannot be reduced due to the work of the high-voltage equipment during the power supply period, so that the battery equipment cannot meet the working voltage of the low-voltage equipment. Further, stability of the high-voltage device in the vehicle is ensured when the above steps S101 to S103 are performed. And avoiding the over-discharge of the generator caused by the fact that the output power of the generator is larger than the maximum output power of the generator.

S102, adjusting the voltage of the high-voltage battery equipment to be the pre-charging voltage.

In an embodiment, the pre-charging voltage is a voltage before the high-voltage battery device is powered, which may be set according to practical situations, and is not limited thereto. Wherein, the purpose of prefilling is: the high-voltage current at the moment of powering up the high-voltage battery device is prevented from damaging other electronic components in the high-voltage battery device.

It will be appreciated that the bus voltage in the high voltage battery device will gradually decrease to 0V after the high voltage battery device has stopped operating. At this time, if the relay is directly closed, the high-voltage battery device will output high-voltage current at the moment of power-on, and the bus voltage and the battery voltage provided by the high-voltage battery device have a larger phase difference, so that other electronic components are damaged.

If the low-voltage battery device is used to precharge the high-voltage battery device, the low voltage output from the low-voltage battery device cannot satisfy the precharge voltage required when the high-voltage battery device is precharged. That is, the precharge cannot be completed for the high-voltage battery device.

However, when the DCDC converter is used to convert the low voltage output from the low voltage battery device into the high voltage to precharge the high voltage battery device, the DCDC converter cannot operate because the high voltage battery device stops supplying power. Therefore, the DCDC converter is also powered by the low-voltage battery device. However, when the low-voltage battery device supplies power to the DCDC converter in the high-voltage device, the battery voltage output from the low-voltage battery device to other low-voltage devices will be reduced. Furthermore, there are cases where the voltage received by the low voltage device is far lower than the operating voltage of the low voltage device, resulting in an under-voltage of the low voltage device, which results in that the low voltage device cannot operate normally.

Based on this, the vehicle-mounted device can adjust the voltage of the high-voltage battery device to the precharge voltage through the BMS system. For example, the pre-charge relay (main relay on the positive side in the high-voltage battery device and main relay on the negative side in the high-voltage battery device) in the high-voltage battery device is controlled to be closed by the BMS system to pre-charge the high-voltage battery device. Furthermore, the low-voltage equipment can not work normally while the purpose of pre-charging is achieved.

S103, switching the power supply equipment to be high-voltage battery equipment so as to control the vehicle to be switched to a normal mode; in the normal mode, the relay is closed, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle during operation.

In an embodiment, in normal mode, a relay in the high voltage battery device is closed and can be used to power the powered device. For example, power is supplied to high-voltage devices (drive motors) and low-voltage devices in vehicle devices. That is, the power supply device in the vehicle will be a high-voltage battery device. At this time, the driving motor and the generator can both provide torque for the vehicle, and each electric equipment in the vehicle can work normally to maintain the normal operation of the vehicle.

Specifically, the vehicle-mounted device may send a relay closing instruction to the high-voltage battery device; the relay closing instruction is used for indicating the high-voltage battery equipment to close the relay. And after the relay is closed within the first preset time, the vehicle-mounted equipment is switched to the power supply equipment to be the high-voltage battery equipment so as to control the vehicle to be switched to the normal mode. Otherwise, the vehicle-mounted device may still control the vehicle to travel in the limp-home mode when it is determined that the relay is not closed for the first preset time.

The first preset time may be set according to actual situations, and exemplary, the first preset time may be 10s.

It should be noted that, if the relay is not closed within the first preset time, it may be considered that there is a contact failure of the relay, or there is a failure of other components of the high-voltage battery device, or a failure of the relay closing instruction, or a failure of the pre-charging of the high-voltage battery device (for example, the pre-charging relay in the high-voltage battery device is not closed), and so on. At this time, in order to ensure driving safety, the vehicle-mounted device needs to control the vehicle to still maintain the limp-home running. That is, the power supply equipment within the vehicle will switch back to the generator, while the battery equipment is not operating.

Wherein the high voltage battery device is controlled by the BMS system, and thus, the in-vehicle device can be considered to send a relay closing instruction to the BMS system. The BMS system then responds to the relay closure command to control relay closure in the high voltage battery device.

It should be added that when the relay is not closed within the first preset time, the relay closing instruction may be lost, or the high-voltage battery equipment may be pre-charged and fail. At this time, in order to switch the vehicle to the normal mode as much as possible, the in-vehicle apparatus may execute the target step and the steps subsequent to the target step after the second preset time. The method comprises the following steps of switching a power supply device in a vehicle to be a low-voltage battery device if the vehicle is in a limp-home mode. That is, the in-vehicle apparatus may execute the above steps S101 to S103 again until the vehicle is switched to the normal mode, or the number of execution times of the target step is equal to the preset number.

In an embodiment, the preset number of times may be set according to practical situations, which is not limited. The preset number of times may be 3 times, for example. It will be appreciated that executing steps S101-S103 described above multiple times may avoid situations where the relay is not closed due to accidental failure.

In an embodiment, the second preset time period may be set according to actual situations, which is not limited. When the process of S101 is performed again, the power supply device in the vehicle is switched back to the generator at this time because the vehicle is in the limp-home mode.

It should be noted that, the purpose of the interval second preset duration is to avoid long-time power supply of the low-voltage battery device, and in the second preset duration, the vehicle-mounted device may charge the low-voltage battery device through the generator, so as to ensure that the low-voltage battery device can normally supply power in the process of executing the steps S101-S103, and improve driving safety.

In another embodiment, the second preset time period may be 0s. That is, steps S101 to S103 are directly performed after the control vehicle is driven in the limp-home mode, which is not limited.

In this embodiment, when the vehicle is in the limp-home mode due to the disconnection of the relay of the high-voltage battery device, the driving motor in the vehicle stops working, and the engine is required to drive the vehicle and the generator to work, so as to supply power to the electric equipment (such as the low-voltage device) of the vehicle, and maintain the running of the vehicle. At this time, in order to be able to switch the vehicle to the normal mode, the low-voltage device may be temporarily replaced with a low-voltage battery device in the vehicle to supply power to the low-voltage device. And then, after the voltage of the high-voltage battery equipment is regulated to the pre-charging voltage, the relay is closed, so that the short-circuit condition of the high-voltage battery equipment caused by the closing of the relay can be avoided, and the high-voltage battery equipment is protected. And, after the relay is closed, the high-voltage battery device may normally supply power to the low-voltage device as well as the high-voltage device (e.g., driving motor) instead of the low-voltage battery device and the generator. At this time, the generator and the driving motor can normally provide torque, so that the vehicle can run in a driving mode corresponding to the normal mode. When the generator is in a power supply state, the generator cannot be directly switched to a torque output state, so that in the switching process, the low-voltage equipment can be temporarily powered by the low-voltage equipment first, and the generator is controlled to exit the power supply state on the basis of maintaining the running of the vehicle. For example, the generator is controlled to be in a standby state. Then, after the relay is closed, the generator may be directly switched to a torque output state to provide torque to the vehicle. Based on this, when the relay of the battery device is turned off, the mode of the vehicle can be controlled to be switched to the normal mode, and the driving scene of the vehicle can be improved.

In another embodiment, to further ensure driving safety in the vehicle mode switching process, before switching the power supply device in the vehicle to be the low-voltage battery device, the vehicle-mounted device may further acquire vehicle information of the vehicle, and when determining that the vehicle meets a preset limp-home mode recovery condition according to the vehicle information, switch the power supply device in the vehicle to be the low-voltage battery device; otherwise, when the vehicle is determined to not meet the preset limp mode recovery condition according to the vehicle information, the vehicle is still controlled to maintain limp mode running.

Specifically, the in-vehicle apparatus may acquire the vehicle speed and the accelerator pedal opening of the vehicle. And then, when the vehicle speed is smaller than the preset vehicle speed and the opening degree of the accelerator pedal is smaller than the preset opening degree, determining that the vehicle meets the preset limp-home mode recovery condition. Further, the power supply device in the vehicle is switched to a low-voltage battery device. Otherwise, when the vehicle speed is greater than or equal to the preset vehicle speed and/or the accelerator pedal opening is greater than or equal to the preset opening, determining that the vehicle does not meet the preset limp-home mode recovery condition. Further, the vehicle is still controlled to travel in the limp-home mode.

The preset vehicle speed and the preset opening degree may be set according to actual situations, which is not limited. For example, the preset vehicle speed may be 12Km/h; the preset opening may be 20% of an opening of the accelerator pedal.

In an embodiment, the battery voltage of the battery device is affected when the vehicle is running at a high speed or during a period of large acceleration, so that the battery device cannot normally supply power when the steps S101-S103 are performed. Therefore, in order to secure the running safety, the in-vehicle apparatus needs to control the running of the vehicle at a low speed.

In which the vehicle speed of the vehicle is typically displayed in the dashboard of the vehicle, and thus, it can be considered that there is a device in the vehicle that collects the vehicle speed. Such as a vehicle speed sensor. And the accelerator pedal opening may be determined from an accelerator sensor.

In summary, in an embodiment, referring to fig. 2, fig. 2 is a flowchart illustrating a vehicle control method according to another embodiment of the present application. The vehicle-mounted device is explained by taking a vehicle control unit VCU as an example. When the vehicle is determined to be in a limp-home mode, the VCU may acquire a battery temperature of the high-voltage battery device, and heat the high-voltage battery device through waste heat generated by engine operation when the battery temperature is lower than or equal to a preset temperature until the battery temperature is higher than the preset temperature. Then, when the battery temperature is higher than the preset temperature, the remaining capacity and the battery voltage of the battery device, as well as the vehicle speed and the accelerator pedal opening of the vehicle, may be acquired. And then, when the residual electric quantity, the battery voltage, the speed of the vehicle and the opening degree of the accelerator pedal meet preset conditions, switching the power supply equipment to be the low-voltage battery equipment. Otherwise, the vehicle is controlled to maintain limp mode driving. Wherein, the preset conditions are: the residual electric quantity is larger than the preset electric quantity, the battery voltage is larger than the working voltage of low-voltage equipment in the vehicle when the low-voltage equipment works, the vehicle speed is smaller than the preset vehicle speed, and the opening of the accelerator pedal is smaller than the preset opening.

At this time, after the switching power supply device is the low-voltage battery device, the vehicle-mounted device may adjust the voltage of the high-voltage battery device to the precharge voltage, and send a relay closing instruction to the high-voltage battery device. And then detecting that the relay is closed within a first preset time, namely, considering that the controlled vehicle is switched to a normal mode. Otherwise, if the relay is not closed within the first preset time, the vehicle is continuously controlled to maintain the limp mode to run for a second preset time. And then, repeatedly executing the steps S101-S103 until the vehicle is switched to the normal mode, or repeatedly executing the steps for a preset number of times, and still not switching the vehicle to the normal mode, the vehicle-mounted equipment can control the vehicle to maintain the limp-home mode to run.

In the process of executing the steps S101 to S103, the operation state between the respective devices (such as the high-voltage battery device, the low-voltage battery device, and the generator) in the vehicle is changed to: in a limp-home mode, the generator is required to supply power to electrical equipment (e.g., low voltage equipment) in the vehicle when in operation, and is in a power supply state; the relay in the high-voltage battery equipment is disconnected, and the high-voltage battery equipment can be in a stop working state. After that, when the above S101 is performed to switch the power supply device in the vehicle to the low-voltage battery device, the generator does not need to supply power. Thus, the generator may exit the power state, e.g., may be in a Standby state (Standby). At this time, the battery device is in a power supply state, and the operating state of the high-voltage battery device may be in a standby state.

Then, after the relay is closed, the high-voltage battery device supplies power to the electrical equipment (e.g., a drive motor) in the vehicle. At this time, the high-voltage battery device is in a working state, the high-voltage battery device can stop supplying power, and is in a stopped working state or a standby state, and the generator and the driving motor can normally supply torque. I.e. the generator and the drive unit are in torque output state (Buck). To sum up, the switching of the operation states between the respective devices in the vehicle when the vehicle control method is executed is described.

In an embodiment, referring to fig. 3, fig. 3 is a schematic diagram illustrating operation of each device in a vehicle according to a vehicle control method according to an embodiment of the present application. Each of the devices includes an in-vehicle device (exemplified by a vehicle controller VCU), a generator, a high-voltage battery device, a DCDC converter, a drive motor, a high-voltage device, and a low-voltage battery device (exemplified by a 12V battery).

In the limp mode, the generator is mainly used for supplying power to all electric equipment. For example, the generator may only power the low voltage device. At this time, when in a power supply state, the whole vehicle controller needs to determine a target voltage which should be provided by the generator according to the actual working state of each electric equipment, and send a target voltage request to the generator. Then, the generator normally responds to the target voltage request and outputs the target voltage. Then, the actual voltage output by the generator may fluctuate so as to be greater than or less than the target voltage. Therefore, the generator also needs to detect the actual voltage and the actual current output at each moment and send the actual voltage and the actual current to the whole vehicle controller, so that the whole vehicle controller determines the output power of the generator based on the actual voltage and the actual current, and the situation that the output power provided by the generator cannot meet the normal consumption of low-voltage equipment is avoided.

In addition, when the control vehicle is switched to the normal mode, the generator is mainly used to output driving torque to drive the vehicle to run. Therefore, during the mode switching process, when the low-voltage device of the vehicle is powered by the 12V battery, the vehicle controller needs to send a standby request to the generator to switch the generator from the power supply state to the standby state (standby). And then, the whole vehicle controller can send a target torque working request to the generator according to the driving requirement of the vehicle in the normal mode, so that the generator switches the working state into a torque output state and outputs the target torque. And then, the generator can also detect the actual torque output by the generator and send the actual torque to the whole vehicle controller, so that the whole vehicle controller determines whether the target torque provided by the generator needs to be adjusted or not based on the actual torque. Based on this, the vehicle control unit may also be considered to have a function of controlling the state of a vehicle power system (a system composed of power equipment such as an engine, a generator, and a drive motor).

For the high-voltage battery device, the embodiment of the application aims at the implementation scene of the relay disconnection in the limp state, so that the high-voltage battery device needs to detect the state (the disconnection state or the closing state) of the relay and send the state to the whole vehicle controller. Thereafter, the vehicle controller may send a relay control request (e.g., a relay closing request) to the high-voltage battery device after adjusting the voltage of the high-voltage battery device to the precharge voltage, so that the high-voltage battery device controls the relay to be closed. That is, the high-voltage battery device has a function of controlling the state of the relay.

Wherein, due to the battery performance of the high-voltage battery device itself, the relay needs to be closed when the battery temperature of the high-voltage battery device is greater than a preset temperature (-30 ℃ or-10 ℃). Therefore, the high-voltage battery device also needs to detect the battery temperature of the high-voltage battery device and upload the battery temperature to the vehicle controller. And, the vehicle controller may send a relay control request (e.g., a relay disconnection request) to the high-voltage battery device to control the relay disconnection when the battery temperature of the high-voltage battery device is less than a preset temperature.

And the whole vehicle controller can also determine the required voltage which the high-voltage battery equipment should provide according to the actual working state of each electric equipment, and send a required voltage request to the high-voltage battery equipment so that the high-voltage battery equipment can output the required voltage. And then, the high-voltage battery equipment normally responds to the request of the required voltage and outputs the required voltage. The actual voltage output by the high-voltage battery device may fluctuate so as to be greater than or less than the required voltage. Therefore, the high-voltage battery device also needs to detect the actual voltage and the actual current output at each moment and send the actual voltage and the actual current to the whole vehicle controller, so that the whole vehicle controller determines the output power of the high-voltage battery device based on the actual voltage and the actual current, and the situation that the output power of the high-voltage battery device cannot meet the normal consumption of each electric equipment is avoided. And the high-voltage battery device also needs to determine the available power of the high-voltage battery device at the current battery temperature based on its battery performance. And then, the available power is sent to the whole vehicle controller, so that the whole vehicle controller can adjust the output power of the high-voltage battery equipment based on the available power, and the power overdischarge generated by the high-voltage battery equipment is avoided.

For DCDC converters, they are responsible for voltage conversion between various low voltage devices. Also, in limp-home mode, the generator may output a voltage much higher than the operating voltage of the low voltage device. Therefore, the DCDC converter needs to convert the target voltage supplied from the generator into a low voltage to supply power to each low voltage device in the limp-home mode. Therefore, in the limp-home mode, the DCDC converter needs to switch the standby state to the operating state in response to a state request of the overall vehicle controller.

In the limp-home mode, the whole vehicle controller needs to determine the output power of the generator according to the working consumption of each low-voltage device. Therefore, the DCDC converter needs to detect its own actual current and actual voltage and send the detected actual current and actual voltage to the vehicle controller, so that the vehicle controller can determine the power consumption of the low-voltage device during operation. In addition, in the normal mode, the actual voltage for externally supplying power to the high-voltage battery equipment is also larger than the working voltage of the low-voltage equipment. Therefore, the DCDC converter still needs to be in operation. That is, the vehicle control unit has a function of controlling the operation state of the DCDC converter.

With the drive motor, in the limp-home mode, the vehicle is driven by the engine, and at this time, the high-voltage device (drive motor) cannot be supplied with power due to the relay in the high-voltage battery device being turned off. Therefore, the actual state of the drive motor is the standby state in the limp-home mode. In the normal mode, the vehicle can be driven by the driving motor or the engine, and at the moment, the driving motor needs to switch the actual state of the vehicle according to the state request output by the whole vehicle controller. For example, when switching to the operating state, the drive motor may respond to the required torque sent from the vehicle controller and provide the required torque to the vehicle. That is, the vehicle control unit has a function of controlling the operation state of the drive motor.

For the high-voltage device, when the relay of the high-voltage battery device is disconnected, the high-voltage device can be controlled to be in a standby state. And after the relay is closed, switching is performed according to a state request sent by the whole vehicle controller. Therefore, the situation that the electric quantity of the high-voltage battery equipment is greatly consumed because the high-voltage equipment is in a working state in the mode switching process can be avoided. Furthermore, the power supply time of the low-voltage battery equipment can be prolonged, so that the whole vehicle controller has enough time to execute the vehicle control method. In summary, the vehicle control unit may be considered to have a function of controlling the operating state of the high-voltage device.

For the low-voltage battery equipment, when the power supply equipment in the vehicle is switched to the low-voltage battery equipment, the battery state of the low-voltage battery equipment needs to meet preset requirements so as to ensure that the low-voltage battery equipment can stably supply power to the low-voltage equipment when the mode of the vehicle is switched. For example, the remaining capacity of the low-voltage battery device needs to be larger than the preset capacity, and the actual battery voltage needs to be larger than the operating voltage when the low-voltage device is operated. Therefore, when determining whether the power supply device in the vehicle needs to be switched to the low-voltage battery device, the whole vehicle controller needs to acquire parameters such as the residual electric quantity and the battery voltage from the low-voltage battery device to determine. That is, the whole vehicle controller has a function of detecting the battery state of the battery device.

In another embodiment, in order to ensure the driving safety when switching the modes of the vehicle, the vehicle state of the vehicle is also considered. For example, the whole vehicle controller may acquire a vehicle speed and an accelerator pedal opening of the vehicle based on the respective sensor devices, and switch a power supply device in the vehicle to be a low-voltage device when the vehicle speed is less than a preset vehicle speed and the accelerator pedal opening is less than the preset opening. That is, the whole vehicle controller has a function of detecting the state of the vehicle.

Referring to fig. 4, fig. 4 is a block diagram of a vehicle control apparatus according to an embodiment of the application. The vehicle control apparatus in this embodiment includes modules for executing the steps in the embodiments corresponding to fig. 1 and 2. Refer specifically to fig. 1 and fig. 2 and the related description in the embodiments corresponding to fig. 1 and fig. 2. For convenience of explanation, only the portions related to the present embodiment are shown. Referring to fig. 4, the vehicle control apparatus 400 may include: a first switching module 410, a regulating module 420, and a first control module 430, wherein:

a first switching module 410, configured to switch the power supply device in the vehicle to be a low-voltage battery device if the vehicle is in a limp-home mode; in a limp-home mode, a relay of a high-voltage battery device in the vehicle is disconnected, a driving motor in the vehicle stops working, and a power supply device comprises a generator.

The adjusting module 420 is configured to adjust the voltage of the high-voltage battery device to the pre-charge voltage.

A first control module 430 for switching the power supply device to a high-voltage battery device to control the vehicle to switch to a normal mode; in the normal mode, the relay is closed, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle during operation.

In an embodiment, the vehicle control apparatus 400 further includes:

and the first acquisition module is used for acquiring the battery temperature in the high-voltage battery equipment.

And the heating module is used for heating the high-voltage battery equipment based on waste heat generated by the engine when the vehicle runs in the limp mode until the battery temperature is higher than the preset temperature if the battery temperature is lower than or equal to the preset temperature.

In an embodiment, the vehicle control apparatus 400 further includes:

and the second acquisition module is used for acquiring the residual electric quantity and the battery voltage of the battery equipment.

And the second switching module is used for switching the power supply equipment in the vehicle to be low-voltage battery equipment if the residual electric quantity is larger than the preset electric quantity and the battery voltage is larger than the working voltage of the low-voltage equipment in the vehicle during working.

In an embodiment, the vehicle control apparatus 400 further includes:

And the third acquisition module is used for acquiring the speed of the vehicle and the opening degree of the accelerator pedal.

And the third switching module is used for switching the power supply equipment in the vehicle to be the low-voltage battery equipment if the vehicle speed is smaller than the preset vehicle speed and the opening of the accelerator pedal is smaller than the preset opening.

In an embodiment, the vehicle control apparatus 400 further includes:

the sending module is used for sending a relay closing instruction to the high-voltage battery equipment; the relay closing instruction is used for indicating the high-voltage battery equipment to close the relay.

And the second control module is used for switching the power supply equipment to be high-voltage battery equipment if the relay is closed within the first preset time.

In an embodiment, the vehicle control apparatus 400 further includes:

and the third control module is used for controlling the vehicle to maintain the limp mode to run if the relay is not closed within the first preset time.

In an embodiment, the vehicle control apparatus 400 further includes:

the execution module is used for executing the target step and the steps after the target step after the second preset time until the vehicle is switched to a normal mode or the execution times of the target step are equal to the preset times; the target step is to switch the power supply equipment in the vehicle to be low-voltage battery equipment if the vehicle is in a limp-home mode.

It should be understood that, in the block diagram of the vehicle control device shown in fig. 4, each module is configured to perform each step in the embodiment corresponding to fig. 1 and 2, and each step in the embodiment corresponding to fig. 1 and 2 is explained in detail in the foregoing embodiment, and specific reference is made to fig. 1 and 2 and the related description in the embodiment corresponding to fig. 1 and 2, which are not repeated herein.

Fig. 5 is a block diagram of a vehicle according to an embodiment of the present application. As shown in fig. 5, the vehicle 500 of this embodiment includes: a processor 510, a memory 520, and a computer program 530 stored in the memory 520 and executable on the processor 510, such as a program of a vehicle control method. The steps in the respective embodiments of the above-described vehicle control method are implemented when the processor 510 executes the computer program 530, for example, S101 to S103 shown in fig. 1. Alternatively, the processor 510 may perform the functions of the modules in the embodiment corresponding to fig. 4, for example, the functions of the modules 410 to 430 shown in fig. 4, when executing the computer program 530, and refer to the related description in the embodiment corresponding to fig. 4.

For example, the computer program 530 may be divided into one or more modules, one or more modules being stored in the memory 520 and executed by the processor 510 to implement the vehicle control method provided by the embodiment of the present application. One or more of the modules may be a series of computer program instruction segments capable of performing particular functions for describing the execution of the computer program 530 in the vehicle 500. For example, the computer program 530 may implement the vehicle control method provided by the embodiment of the present application.

The vehicle 500 may include, but is not limited to, a processor 510, a memory 520. It will be appreciated by those skilled in the art that fig. 5 is merely an example of a vehicle 500 and is not intended to limit the vehicle 500, and may include more or fewer components than shown, or may combine certain components, or different components, e.g., the vehicle may further include input and output devices, network access devices, buses, etc.

The processor 510 may be a central processing unit, as well as other general purpose processors, digital signal processors, application specific integrated circuits, off-the-shelf programmable gate arrays or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, or the like. A general purpose processor may be a microprocessor or the processor may be any conventional processor or the like.

The memory 520 may be an internal storage unit of the vehicle 500, such as a hard disk or a memory of the vehicle 500. The memory 520 may also be an external storage device of the vehicle 500, such as a plug-in hard disk, a smart memory card, a flash memory card, etc. provided on the vehicle 500. Further, the memory 520 may also include both internal storage units and external storage devices of the vehicle 500.

Embodiments of the present application provide a computer-readable storage medium storing a computer program that is executed by a processor to perform the vehicle control method in the above-described embodiments.

Embodiments of the present application provide a computer program product for causing a vehicle to execute the vehicle control method in the respective embodiments described above when the computer program product is run on the vehicle.

The above embodiments are only for illustrating the technical solution of the present application, and are not limiting; although the application has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical scheme described in the foregoing embodiments can be modified or some technical features thereof can be replaced by equivalents; such modifications and substitutions do not depart from the spirit and scope of the technical solutions of the embodiments of the present application, and are intended to be included in the scope of the present application.

Claims

1. A vehicle control method, characterized in that the method comprises:

if the vehicle is in a limp-home mode, switching power supply equipment in the vehicle to be low-voltage battery equipment; the relay of the high-voltage battery equipment in the vehicle is disconnected in the limp mode, the driving motor in the vehicle stops working, and the power supply equipment comprises a generator;

Regulating the voltage of the high-voltage battery equipment to a pre-charge voltage;

switching the power supply equipment to the high-voltage battery equipment to control the vehicle to be switched to a normal mode; the relay is closed in the normal mode, the high-voltage battery device is used for supplying power to the driving motor, and the generator and the driving motor are used for providing torque for the vehicle when working.

2. The method of claim 1, further comprising, prior to said switching the power supply device within the vehicle to a low voltage battery device:

acquiring a battery temperature in the high-voltage battery device;

and if the battery temperature is lower than or equal to a preset temperature, heating the high-voltage battery equipment based on waste heat generated by engine operation when the vehicle runs in the limp mode until the battery temperature is higher than the preset temperature.

3. The method of claim 1, wherein before the switching the power supply device within the vehicle to a low voltage battery device, further comprising:

acquiring battery information of the low-voltage battery equipment;

if the low-voltage battery equipment meets the preset power supply condition according to the battery information, switching the power supply equipment in the vehicle to the low-voltage battery equipment;

And if the low-voltage battery equipment does not meet the preset power supply condition according to the battery information, controlling the vehicle to maintain the limp-home running mode.

4. A method according to claim 3, wherein the battery information includes a remaining power of the battery device and a battery voltage; after the battery information of the battery device is acquired, the method further comprises:

if the residual electric quantity is larger than the preset electric quantity and the battery voltage is larger than the working voltage of the low-voltage equipment in the vehicle during working, determining that the low-voltage equipment meets the preset power supply condition;

and if the residual electric quantity is smaller than or equal to a preset electric quantity and/or the battery voltage is smaller than or equal to the working voltage of the low-voltage equipment in the vehicle during working, determining that the low-voltage battery equipment does not meet the preset power supply condition.

5. The method of claim 1, wherein before the switching the power supply device within the vehicle to a low voltage battery device, further comprising:

acquiring vehicle information of the vehicle;

if the vehicle meets the preset limp mode recovery condition according to the vehicle information, switching power supply equipment in the vehicle to be the low-voltage battery equipment;

And if the vehicle is determined to not meet the preset limp mode recovery condition according to the vehicle information, controlling the vehicle to maintain the limp mode to run.

6. The method of claim 5, wherein the vehicle information includes vehicle speed and accelerator pedal opening; before the switching of the power supply device in the vehicle to the low-voltage battery device, further comprising:

if the vehicle speed is smaller than a preset vehicle speed and the accelerator pedal opening is smaller than a preset opening, determining that the vehicle meets a preset limp-home mode recovery condition;

and if the vehicle speed is greater than or equal to a preset vehicle speed and/or the accelerator pedal opening is greater than or equal to a preset opening, determining that the vehicle does not meet a preset limp-home mode recovery condition.

7. The method of claim 1, further comprising, after said switching the power supply device within the vehicle to a low voltage battery device:

controlling high-voltage equipment in the vehicle to stop working;

after the switching of the power supply device to the high-voltage battery device, further comprising:

and controlling the high-voltage equipment in the vehicle to work normally.

8. The method of any of claims 1-7, further comprising, after said adjusting the voltage of the high voltage battery device to a precharge voltage:

Sending a relay closing instruction to the high-voltage battery equipment; the relay closing instruction is used for indicating the high-voltage battery equipment to close the relay;

and if the relay is closed within the first preset time, switching the power supply equipment to be the high-voltage battery equipment.

9. The method of claim 8, further comprising, after the sending a relay close command to the high voltage battery device:

and if the relay is not closed within the first preset time, controlling the vehicle to maintain the limp mode to run.

10. The method of claim 9, further comprising, after maintaining the limp mode if the relay is not closed within the first preset time:

after a second preset time, executing a target step and steps after the target step until the vehicle is switched to the normal mode, or the execution times of the target step are equal to preset times; the target step is to switch the power supply equipment in the vehicle to be the low-voltage battery equipment if the vehicle is in a limp-home mode.

11. A vehicle comprising a memory, a processor and a computer program stored in the memory and executable on the processor, wherein the processor implements the method of any one of claims 1 to 10 when the computer program is executed.