CN112124300A

CN112124300A - Vehicle limp control method and controller

Info

Publication number: CN112124300A
Application number: CN202010910029.9A
Authority: CN
Inventors: 陈河; 宋海军; 张�浩; 郝阳; 王林啸; 张庚楠; 吴麦青
Original assignee: Great Wall Motor Co Ltd
Current assignee: Great Wall Motor Co Ltd
Priority date: 2020-09-02
Filing date: 2020-09-02
Publication date: 2020-12-25

Abstract

The invention relates to the technical field of vehicle control, and provides a vehicle limp control method and a controller. The vehicle limp home control method includes: when the fact that the vehicle meets a preset limp-home mode activation condition is determined, controlling an engine to drive a motor to generate power and output voltage to a DCDC converter, wherein the limp-home mode activation condition comprises the fact that a high-voltage battery of the vehicle fails to provide energy for the whole vehicle due to a preset fault and the engine and the motor do not have faults; and determining whether the DCDC converter can work normally, if so, limiting the vehicle to run at a first speed and controlling the DCDC converter to supply power to the vehicle electrical equipment, otherwise, limiting the vehicle to run at a second speed, wherein the first speed is greater than the second speed. The scheme of the invention can exert the characteristics of a plurality of power sources of the vehicle, realize vehicle limping, avoid the condition that the vehicle cannot be electrified to run after the power battery fails, and widen the use scene of the vehicle.

Description

Vehicle limp control method and controller

Technical Field

The invention relates to the technical field of vehicle control, in particular to a vehicle limping control method and a controller.

Background

With the continuous development of new energy automobile technology, the functions of hybrid vehicles are becoming more and more abundant. Correspondingly, control strategies for hybrid vehicles are also in a period of intense development, which are constantly optimized to ensure full performance of the functions of the hybrid vehicle.

However, the existing hybrid vehicle control strategy is still not perfect, for example, when a high-voltage battery of the vehicle breaks down, the phenomenon that the whole vehicle cannot be powered on occurs, so that the vehicle cannot run and only depends on rescue. That is, the conventional vehicle control strategy cannot solve the problem that the vehicle cannot run due to the failure of the high-voltage battery, so that the functions of the vehicle cannot be fully exerted, and the use scene of the vehicle is limited.

Disclosure of Invention

In view of the above, the present invention is directed to a limp home control method for a vehicle to solve the problem that the vehicle cannot run due to a failure of a high voltage battery.

In order to achieve the purpose, the technical scheme of the invention is realized as follows:

a vehicle limp home control method, the vehicle having an engine, a motor connected to the engine, and a DCDC converter connected to the motor, the vehicle limp home control method comprising: when the fact that the vehicle meets a preset limp-home mode activation condition is determined, the engine is controlled to drive the motor to generate electricity and output voltage to the DCDC converter, wherein the limp-home mode activation condition comprises the fact that a high-voltage battery of the vehicle fails to provide energy for the whole vehicle due to a preset fault and the engine and the motor are not in fault; and determining whether the DCDC converter can work normally, if so, limiting the vehicle to run at a first speed and controlling the DCDC converter to supply power to the vehicle electrical equipment, otherwise, limiting the vehicle to run at a second speed, wherein the first speed is greater than the second speed.

Further, after the determining that the vehicle meets the preset limp home mode activation condition, the vehicle limp home control method further includes: activating a flag indicating that the limp home mode has been activated and sending the flag to the engine, the motor, and/or the DCDC converter.

Further, the controlling the engine to drive the motor to generate power and output voltage to the DCDC converter includes: when the vehicle is in a stop state, controlling a starter of the vehicle to start the engine so as to drive the motor to generate power and output voltage to the DCDC converter; or when the vehicle is in a running state, the engine is directly started to drive the motor to generate electricity and output voltage to the DCDC converter; wherein the limp home mode activation condition further comprises no starter failure.

Further, the vehicle limp home control method is executed at a vehicle controller side of a vehicle, and the vehicle controller is one of the electrical devices used in the vehicle, the vehicle limp home control method further includes: and in the process that the engine drives the motor to generate power and outputs voltage to the DCDC converter, controlling the motor to increase the output voltage in a gradient manner until the output voltage is stabilized at the voltage requirement value of the vehicle controller of the vehicle, and controlling the DCDC to enter a working mode.

Further, the vehicle limp home control method further includes: and controlling the motor to be in a power generation mode and quit a driving mode in the process of generating power by the motor.

Further, if the vehicle further has another electric machine not connected to the engine, the vehicle limp home control method further includes: and controlling the other motor to exit the working mode.

Further, when the limiting vehicle operates at the second speed, the vehicle limp home control method further includes: the second speed is determined as a function of the state of charge of a battery for supplying the vehicle electrical system and/or the current voltage of the battery.

Further, the vehicle limp home control method further includes: and partially or totally limiting the comfort function of the whole vehicle according to the low-voltage side power of the DCDC converter, the generated power generated by the motor and/or the charge state of a storage battery for supplying power to the electric device for the vehicle.

Compared with the prior art, the vehicle limp home control method has the following advantages: the vehicle limping control method can exert the characteristic that the vehicle has a plurality of power sources, realize vehicle limping, avoid the condition that the vehicle cannot be electrified to run after a power battery fails, and widen the use scene of the vehicle.

Another object of the present invention is to provide a machine-readable storage medium to solve the problem of the vehicle being unable to run due to the failure of the high voltage battery.

a machine-readable storage medium having instructions stored thereon for causing a machine to perform the vehicle limp home control method described above.

The machine-readable storage medium has the same advantages as the vehicle limp home control method described above over the prior art and will not be described herein again.

Another objective of the present invention is to provide a vehicle controller to solve the problem that the vehicle cannot run due to the failure of the high-voltage battery.

a vehicle controller for running a program, wherein the program is run to perform: the vehicle limp home control method as described above.

The vehicle controller has the same advantages of the vehicle limp home control method compared with the prior art, and the detailed description is omitted.

Additional features and advantages of the invention will be set forth in the detailed description which follows.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate an embodiment of the invention and, together with the description, serve to explain the invention and not to limit the invention. In the drawings:

FIG. 1 is a schematic illustration of the operating state of a powertrain of a vehicle as contemplated by an embodiment of the present invention;

FIG. 2 is a schematic flow diagram of a vehicle limp home control method of an embodiment of the present invention;

fig. 3 is a flowchart illustrating an example of vehicle control using the vehicle limp home control method according to the embodiment of the invention; and

fig. 4 is a signal flow diagram of an exemplary HCU control strategy in accordance with an embodiment of the present invention.

Description of reference numerals:

110. an engine; 120. a motor; 130. a DCDC converter; 140. a high voltage battery; 150. a storage battery; 160. another motor; 170. an electric device for a vehicle.

Detailed Description

In addition, the embodiments of the present invention and the features of the embodiments may be combined with each other without conflict.

It should be noted that, in the embodiment of the present invention, the limp home mode refers to that when some faults occur to the vehicle, the vehicle can still go home or go to a nearby vehicle repair shop for repair. In addition, in the embodiment of the invention, the high-voltage battery and the power battery can be equally understood.

The present invention will be described in detail below with reference to the accompanying drawings in conjunction with embodiments.

The embodiment of the invention provides a vehicle limp control method, which is used for enabling a vehicle to activate a limp mode to continue running under the condition that the whole vehicle cannot be powered up due to the fault of a high-voltage battery. In order to more clearly describe the vehicle limp home control method according to the embodiment of the present invention, a brief description is first given of a powertrain of a vehicle according to the embodiment of the present invention.

Fig. 1 is a schematic diagram of an operating state of a power system of a vehicle according to an embodiment of the present invention, wherein the vehicle is preferably a hybrid vehicle, and the hybrid vehicle is taken as an example hereinafter. For a hybrid vehicle, the powertrain may include: engine 110, motor 120 connected to engine 110, DCDC converter 130 connected to motor 120, high-voltage battery 140 electrically connected to DCDC converter 130, and battery 150. Preferably, the power system may further include another motor 160 not connected to the engine 110, and an On Board Charger (OBC) electrically connected to the two motors and the DCDC converter 130.

The electric machine 120 may be coupled to the engine 110 via a Belt (e.g., Belt drive Starter Generator (BSG)) or a mechanical coupling or a clutch (e.g., P2 electric machine) or a direct coupling (e.g., a Governor (GM)).

The voltage output by the motor 120 for generating power and the voltage output by the high voltage battery 140 are provided to the DCDC converter 130, and the DCDC converter 130 is used for converting a high voltage into a low voltage to supply power to the vehicle electrical device 170. The battery 150 is, for example, a 12V battery, which can also be used to supply power to the vehicle electrical components 170, but which only ensures short-term, low-power-consumption vehicle operation in relation to the supply of power by the DCDC converter 130. In addition, the high voltage battery 140 according to the embodiment of the present invention may be a 48V lithium battery, but is not limited to a 48V lithium battery, and a high voltage battery with a voltage higher than 48V is also suitable for the vehicle limp home control method according to the embodiment of the present invention. In addition, the four blank boxes in fig. 1 represent wheels, and the connections between the wheels and the engine and the motor are well known in the art and will not be described herein.

Fig. 2 is a schematic flow diagram of a vehicle limp home Control method according to an embodiment of the present invention, which is applied to, for example, a Hybrid Control Unit (HCU) of a vehicle, and may include the following steps S210 and S220:

step S210, when it is determined that the vehicle satisfies the preset limp home mode activation condition, controlling the engine 110 to drive the motor 120 to generate power and output voltage to the DCDC converter 130.

Wherein the limp home mode activation condition comprises: the high-voltage battery 140 of the vehicle has a preset fault and cannot provide energy for the whole vehicle; and the engine 110 and the motor 120 are not faulty. For example, the high-voltage battery 140 has an insulation fault or a high-voltage interlock fault, so that energy cannot be continuously supplied to the entire vehicle; the engine 110 and the motor 120 are not faulty and can be in their respective operating modes.

Preferably, after said determining that the vehicle meets a preset limp home mode activation condition, a flag indicating that the limp home mode has been activated may be generated and sent to the engine, the motor and/or the DCDC converter to inform them that they are ready to enter an operating state in limp home mode.

Preferably, the engine-driven motor power generation in step S210 may further include, for different vehicle states:

1) for a vehicle with a starter, when the vehicle is in a stop state, controlling the starter of the vehicle to start the engine 110, so as to drive the motor 120 to generate power and output voltage to the DCDC converter 130; or

2) When the vehicle is in a running state, the engine 110 is directly started to drive the motor 120 to generate power and output voltage to the DCDC converter 130. The 2) solution may be for a vehicle with a starter, or for a vehicle without a 12V starter, for example. For example, for a vehicle without a 12V starter, a limp home mode may also be entered, but with the proviso that the engine must be in operation (corresponding to the vehicle being in operation) before the limp home mode is activated. The vehicle is in a running state, which indicates that the engine 110 is in a working mode, so that the engine is started, namely the engine is in a running state before the limp home mode is activated, and the vehicle is in a stopping state, which indicates that the engine 110 may not be in the working mode, so that the engine is started by using the starter, so that the engine is controlled to drive the motor to rotate to generate electricity. Accordingly, it can be seen that after the limp home mode of the embodiment of the present invention is activated, the engine needs to be in the operating mode, i.e., the engine is inhibited from being stopped, so that the corresponding hybrid vehicle cannot perform the electric-only mode.

Further, corresponding to such a case of applying a starter, the limp home mode activation condition may further include that the starter is not failed.

Preferably, for this step S210, in order to ensure the maximum power supply of the motor in the limp home mode, the motor 120 may be controlled to be in the power generation mode and exit the driving mode during the power generation of the motor 120. The driving mode includes that the motor is used for torque control or rotating speed control, and the driving mode is exited, so that the motor 120 only generates power to supply power to the DCDC converter 130 for supplying power to the whole vehicle.

More preferably, referring to fig. 1, for a vehicle with two front and rear motors, the other motor 160 may be further controlled to exit from the operating mode and enter into an initialization or sleep state to ensure the stability of the voltage output by the power generation of the motor 120 in the power generation mode.

Step S220, determining whether the DCDC converter 130 can normally operate, if so, limiting the vehicle from operating at a first speed and controlling the DCDC converter 130 to supply power to the electrical device 170 for the vehicle, otherwise, limiting the vehicle from operating at a second speed.

Wherein the first speed is greater than the second speed. For example, the first speed is 140km/h, and the second speed is a safe vehicle speed of 30km/h-60 km/h. That is, when the DCDC converter 130 works normally, a slight speed limit (for example, 140km/h) is performed on the vehicle relative to the original vehicle speed, and the DCDC converter 130 converts the high voltage into the low voltage and supplies the low voltage to the low voltage network of the vehicle, so that the corresponding electric devices for the vehicle are powered from the low voltage network to run, thereby ensuring that the vehicle continues to run according to the conventional running mode to the maximum extent; and when the DCDC converter cannot work normally, limiting the speed of the vehicle to a safe vehicle speed (such as a second speed of 30km/h-60km/h) so as to ensure the safe operation of the vehicle.

In a preferred embodiment, for the second speed, it may be determined according to a State of Charge (SOC) of the battery and/or a current voltage of the battery. For example, in the case of a 12V battery, the power supply capacity is not as good as that of the DCDC converter, so that when the DCDC cannot work normally, the vehicle is speed-limited according to the SOC or voltage of the battery 150, so that the vehicle speed is below a safe vehicle speed, and the vehicle can limp for a short time, for example, complete a vehicle moving operation. In a more preferred embodiment, when the DCDC converter cannot work normally, if the SOC or voltage of the DCDC converter is lower than a calibrated value, the power off of the entire vehicle can be directly requested to ensure the safety of the vehicle.

Therefore, while the power generation by the motor 120 of the vehicle is realized in step S210, the embodiment of the present invention performs the speed-limited limp of the vehicle according to the operation condition of the DCDC converter 130 in step S220, so that the vehicle maximally ensures that the vehicle continues to run in the conventional running mode when the DCDC converter is normally powered, and ensures that the vehicle safely runs to complete a simple operation when the DCDC converter fails. In a preferred embodiment, it may also be included whether the DCDC converter 130 is able to operate normally into the limp home mode activation condition described in step S210.

Preferably, the methods of steps S210 and S220 may be performed at the HCU of the vehicle, which is one of the electrical devices for the vehicle and needs to be powered by the DCDC converter 130. Accordingly, the vehicle limp home control method according to the embodiment of the present invention may further include the steps of:

in the process that the engine 110 drives the motor 120 to generate power and output voltage to the DCDC converter 130, the motor 120 may be controlled to gradually increase the output voltage with a certain gradient, i.e., a gradient boost, until the output voltage is stabilized at a voltage requirement value of, for example, an HCU of a vehicle, and then the DCDC converter is controlled to enter a working mode.

The purpose of performing gradient boosting is to pre-charge the motor 120 and the DCDC converter 130, so as to avoid the damage to the motor 120, the DCDC converter 130 or other electric devices due to the impact on the entire vehicle high-voltage network caused by sudden and large increase of voltage. Thus, this step ensures that the HCU can normally execute the vehicle control strategy including the vehicle limp home control method of the embodiment of the invention.

Further, after the output voltage of the motor 120 is stabilized, the stabilized output voltage is required to be within the allowable input voltage range of the DCDC converter 130, and preferably, the low-voltage power supply is satisfied, and a certain calibration value is not allowed to be exceeded.

Preferably, the vehicle limp home control method may further include: and partially or totally limiting the comfort function of the whole vehicle according to the low-voltage side power of the DCDC converter 130, the generated power generated by the motor 120 and/or the SOC of the storage battery.

Wherein the comfort functions, such as seat adjustment, seat heating, air conditioning, entertainment functions, etc., are functions that are not directly related to the operation of the vehicle. As can be seen from the above, both the DCDC converter 130 and the storage battery can directly supply power to the vehicle electrical devices, and in the event of a failure of the high-voltage battery, the power supply capability of the DCDC converter to the vehicle depends on the power generation capability of the motor. Thus, for example, when one or more of the low-voltage side power of the DCDC converter, the generated power of the motor for generating power, and the SOC of the battery is greater than respective preset power supply capacity values, the comfort function, such as the air conditioning, may be partially restricted while the seat adjustment function is retained; the comfort function may be all restricted to prioritize the limp-home running of the vehicle when the low-side power of the DCDC converter 130, the generated power of the motor 120 and the SOC of the battery are less than respective preset power supply capability values.

In summary, the vehicle limping control method provided by the embodiment of the invention can exert the characteristic that the hybrid vehicle has a plurality of power sources, avoid the situation that the vehicle cannot be powered on to run after the power battery fails, broaden the use scenes of the hybrid vehicle, has technical leadership, has strategy compatibility between the production process and the use scenes of users, and is convenient and controllable in strategy.

The application of the vehicle limp home control method of the embodiment of the present invention will be specifically described below by way of example.

Fig. 3 is a schematic flow diagram of an example of vehicle control using the vehicle limp home control method of an embodiment of the invention, in which the HCU executes the corresponding vehicle limp home control method, and the various components associated with the electric machine generation in the vehicle limp home control method are collectively referred to as the electric power generation components, whereby the strategy of the method shown in fig. 3 can be described as the signal flow diagram shown in fig. 4. Accordingly, fig. 4 is a signal flow diagram of an exemplary HCU control strategy of an embodiment of the present invention, which indicates that the corresponding control strategy is: the HCU receives the high-voltage battery signal stream, the engine signal stream, the motor signal stream, and the DCDC signal stream, generates a control signal stream based on the signal streams, and transmits the generated control signal stream to the engine, the motor, the DCDC, the starter, and the like, to implement vehicle limp control.

More specifically, as shown in fig. 3, this example may include the steps of:

and S301, judging whether the limp home mode activation condition is met, if so, executing the S301, and otherwise, exiting the limp home mode.

Therein, the example limp-home mode activation condition may for example comprise the following five points:

1) the high-voltage battery fails (non-insulation or non-high-voltage interlocking failure) and cannot continuously provide energy for the whole vehicle.

If the high-voltage battery has an insulation fault or a high-voltage interlocking fault, the whole vehicle is controlled to be powered off immediately to ensure the safety of the vehicle.

2) The engine is not faulty, allowing it to be in working mode.

3) The electric machine connected to the engine is not faulty, allowing a limp home mode.

4) The starter is not in failure and the start can be completed (if the starter is not available, the start can be ignored).

Wherein, the starter is preferably a 12V conventional starter.

5) The DCDC converter has no fault and can provide a required 12V power supply for the whole vehicle;

step S302, activating a flag bit for showing that the limp home mode has been activated, and sending the flag bit to the power generation means.

In step S303, the power generation component receives the flag bit and feeds back to the HCU that it is ready to enter the limp home mode.

In step S304, the engine state is detected, and if the engine state is not in the running state, step S305a is executed, and if the engine state is in the running state, step S305b is executed.

Step S305a, the HCU sends a first instruction, and the first instruction is used for instructing a starter to start an engine to drive a motor to operate; in step S305b, the HCU issues a second command for the engine to be at the target speed to operate the motor.

And step S306, the corresponding power generation component receives and responds to the first instruction or the second instruction, and feeds back a response result to the HCU. Specifically, the starter, the engine, and the electric machine receive a first command, and the engine and the electric machine receive a second command.

In step S307, the HCU issues a third instruction for instructing the motor to increase the output voltage in a gradient manner and to output a stable voltage until the required voltage of the HCU.

And step S308, the motor receives and responds to the third instruction and feeds back a response result to the HCU.

Specifically, the motor responds to a third instruction and is driven by the engine to operate so as to generate high-voltage direct current to replace a high-voltage battery to provide energy for electric equipment of the vehicle. In addition, the engine is used for driving the vehicle to run while driving the motor to continuously generate electricity.

In step S309, the HCU issues a fourth instruction, where the fourth instruction is used to instruct the DCDC converter to enter the operating mode for low-voltage power supply.

Preferably, the fourth command may also instruct the power battery system to power down.

In step S310, the DCDC converter receives and responds to the fourth instruction, and feeds back a response result to the HCU.

Preferably, when the fourth command also indicates that the power battery system is to be de-energized, the power battery system also receives and responds to the fourth command and feeds back the response to the HCU.

After step S310, the vehicle electric devices including the HCU may be powered from the DCDC converter so that the vehicle limp home mode may be normally performed.

In conclusion, the limp running of the vehicle is realized by the motor, the situation that the vehicle cannot run after the power battery fails can be avoided, and the use scenes of the vehicle are widened.

Another embodiment of the present invention also provides a machine-readable storage medium having instructions stored thereon for causing a machine to perform the vehicle limp home control method of the above-described embodiment.

Another embodiment of the present invention also provides a vehicle controller for executing a program, wherein the program is executed to perform: the vehicle limp home control method according to the above embodiment.

The vehicle controller is, for example, an HCU, but may be another controller configured separately.

As will be appreciated by one skilled in the art, embodiments of the present application may be provided as a method, system, or computer program product. Accordingly, the present application may take the form of an entirely hardware embodiment, an entirely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present application may take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage, CD-ROM, optical storage, and the like) having computer-usable program code embodied therein.

The present application is described with reference to flowchart illustrations and/or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the application. It will be understood that each flow and/or block of the flow diagrams and/or block diagrams, and combinations of flows and/or blocks in the flow diagrams and/or block diagrams, can be implemented by computer program instructions. These computer program instructions may be provided to a processor of a general purpose computer, special purpose computer, embedded processor, or other programmable data processing apparatus to produce a machine, such that the instructions, which execute via the processor of the computer or other programmable data processing apparatus, create means for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be stored in a computer-readable memory that can direct a computer or other programmable data processing apparatus to function in a particular manner, such that the instructions stored in the computer-readable memory produce an article of manufacture including instruction means which implement the function specified in the flowchart flow or flows and/or block diagram block or blocks.

These computer program instructions may also be loaded onto a computer or other programmable data processing apparatus to cause a series of operational steps to be performed on the computer or other programmable apparatus to produce a computer implemented process such that the instructions which execute on the computer or other programmable apparatus provide steps for implementing the functions specified in the flowchart flow or flows and/or block diagram block or blocks.

In a typical configuration, a computing device includes one or more processors (CPUs), input/output interfaces, network interfaces, and memory.

The memory may include forms of volatile memory in a computer readable medium, Random Access Memory (RAM) and/or non-volatile memory, such as Read Only Memory (ROM) or flash memory (flash RAM). The memory is an example of a computer-readable medium.

Computer-readable media, including both non-transitory and non-transitory, removable and non-removable media, may implement information storage by any method or technology. The information may be computer readable instructions, data structures, modules of a program, or other data. Examples of computer storage media include, but are not limited to, phase change memory (PRAM), Static Random Access Memory (SRAM), Dynamic Random Access Memory (DRAM), other types of Random Access Memory (RAM), Read Only Memory (ROM), Electrically Erasable Programmable Read Only Memory (EEPROM), flash memory or other memory technology, compact disc read only memory (CD-ROM), Digital Versatile Discs (DVD) or other optical storage, magnetic cassettes, magnetic tape magnetic disk storage or other magnetic storage devices, or any other non-transmission medium that can be used to store information that can be accessed by a computing device. As defined herein, a computer readable medium does not include a transitory computer readable medium such as a modulated data signal and a carrier wave.

It should also be noted that the terms "comprises," "comprising," or any other variation thereof, are intended to cover a non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements does not include only those elements but may include other elements not expressly listed or inherent to such process, method, article, or apparatus. Without further limitation, an element defined by the phrase "comprising an … …" does not exclude the presence of other identical elements in the process, method, article, or apparatus that comprises the element.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

Claims

1. A vehicle limp home control method, characterized in that the vehicle has an engine, a motor connected to the engine, and a DCDC converter connected to the motor, and the vehicle limp home control method comprises:

when the fact that the vehicle meets a preset limp-home mode activation condition is determined, the engine is controlled to drive the motor to generate electricity and output voltage to the DCDC converter, wherein the limp-home mode activation condition comprises the fact that a high-voltage battery of the vehicle fails to provide energy for the whole vehicle due to a preset fault and the engine and the motor are not in fault; and

and determining whether the DCDC converter can work normally, if so, limiting the vehicle to operate at a first speed and controlling the DCDC converter to supply power to vehicle electrical equipment, otherwise, limiting the vehicle to operate at a second speed, wherein the first speed is greater than the second speed.

2. The vehicle limp home control method of claim 1, wherein after the determination that the vehicle meets a preset limp home mode activation condition, the vehicle limp home control method further comprises:

activating a flag indicating that the limp home mode has been activated and sending the flag to the engine, the motor, and/or the DCDC converter.

3. The vehicle limp home control method as claimed in claim 1, wherein the controlling the engine to drive the motor to generate electricity and output a voltage to the DCDC converter comprises:

when the vehicle is in a stop state, controlling a starter of the vehicle to start the engine so as to drive the motor to generate power and output voltage to the DCDC converter; or

When the vehicle is in a running state, directly starting the engine to drive the motor to generate power and output voltage to the DCDC converter;

wherein the limp home mode activation condition further comprises no starter failure.

4. The vehicle limp control method of claim 1, wherein the vehicle limp control method is performed at a vehicle controller side of a vehicle, and the vehicle controller is one of the vehicle electrical devices, the vehicle limp control method further comprising:

and in the process that the engine drives the motor to generate power and outputs voltage to the DCDC converter, controlling the motor to increase the output voltage in a gradient manner until the output voltage is stabilized at the voltage requirement value of the vehicle controller of the vehicle, and controlling the DCDC to enter a working mode.

5. The vehicle limp control method of claim 1, further comprising:

and controlling the motor to be in a power generation mode and quit a driving mode in the process of generating power by the motor.

6. The vehicle limp home control method of claim 1, wherein if the vehicle further has another electric machine not connected to the engine, the vehicle limp home control method further comprises:

and controlling the other motor to exit the working mode.

7. The vehicle limp control method of claim 1, wherein while the restricted vehicle is operating at the second speed, the vehicle limp control method further comprises:

the second speed is determined as a function of the state of charge of a battery for supplying the vehicle electrical system and/or the current voltage of the battery.

8. The vehicle limp control method of claim 1, further comprising:

and partially or totally limiting the comfort function of the whole vehicle according to the low-voltage side power of the DCDC converter, the generated power generated by the motor and/or the charge state of a storage battery for supplying power to the electric device for the vehicle.

9. A machine-readable storage medium having instructions stored thereon for causing a machine to perform the vehicle limp home control method of any one of claims 1 to 8.

10. A vehicle controller for operating a program, wherein the program is executed to perform: the vehicle limp home control method as recited in any one of claims 1 to 8.