CN117719487A

CN117719487A - Hybrid electric vehicle and driving method thereof

Info

Publication number: CN117719487A
Application number: CN202410073380.5A
Authority: CN
Inventors: 饶俊威; 张安伟; 周文太; 张良; 郑智伟; 张轩
Original assignee: Guangzhou Automobile Group Co Ltd
Current assignee: Guangzhou Automobile Group Co Ltd
Priority date: 2024-01-18
Filing date: 2024-01-18
Publication date: 2024-03-19

Abstract

The application belongs to the technical field of new energy automobiles, and particularly relates to a hybrid electric vehicle and a driving method thereof. The driving method of the hybrid electric vehicle includes: when the hybrid electric vehicle accelerates, determining a target rotating speed of an engine according to a battery charge state of a power battery, wherein the target rotating speed is lower than a maximum rotating speed of the engine; when the rotating speed of the engine reaches the target rotating speed, maintaining the rotating speed of the engine unchanged, and adjusting the torque of the engine according to the required power of the driving motor; when the driving mode switching condition is met, the range extending mode of the driving mode of the hybrid electric vehicle, which is driven by the driving motor alone, is switched to the series-parallel mode of the driving motor and the engine together. The method and the device can improve the switching speed of the driving mode of the hybrid electric vehicle.

Description

Hybrid electric vehicle and driving method thereof

Technical Field

The application belongs to the technical field of new energy automobiles, and particularly relates to a hybrid electric vehicle and a driving method thereof.

Background

The hybrid vehicle is a vehicle that can be driven by both gasoline and electric power. In the running process of the hybrid electric vehicle, different driving modes can be switched according to actual requirements. In the process of switching the driving modes of the hybrid electric vehicle, the problem of slower switching speed of the driving modes is caused by the large difference between the rotation speed of the engine and the rotation speed of the wheel end of the vehicle.

Disclosure of Invention

The present application provides a hybrid vehicle and a driving method thereof, and aims to improve the switching speed of a driving mode of the hybrid vehicle.

Other features and advantages of the present application will be apparent from the following detailed description, or may be learned in part by the practice of the application.

According to an aspect of an embodiment of the present application, there is provided a driving method of a hybrid vehicle, the method including:

when the hybrid electric vehicle accelerates, determining a target rotating speed of an engine according to a battery charge state of a power battery, wherein the target rotating speed is lower than a maximum rotating speed of the engine;

when the rotating speed of the engine reaches the target rotating speed, maintaining the rotating speed of the engine unchanged, and adjusting the torque of the engine according to the required power of the driving motor;

when the driving mode switching condition is met, the range extending mode of the driving mode of the hybrid electric vehicle, which is driven by the driving motor alone, is switched to the series-parallel mode of the driving motor and the engine together.

In some embodiments of the present application, based on the above technical solutions, determining the target rotation speed of the engine according to the battery state of charge of the power battery includes:

determining the output power of a power battery according to the battery charge state of the power battery;

determining the required power of the engine according to the output power of the power battery, wherein the required power of the engine and the output power of the power battery are in a negative correlation;

and determining the target rotating speed of the engine according to the required power of the engine.

In some embodiments of the present application, based on the above technical solutions, determining the target rotation speed of the engine according to the required power of the engine includes:

acquiring an external characteristic curve of the engine;

and inquiring the external characteristic curve according to the required power of the engine to obtain the target rotating speed of the engine.

In some embodiments of the present application, based on the above technical solutions, determining the required power of the engine according to the output power of the power battery includes:

obtaining peak power of the driving motor, system efficiency of the driving motor and system efficiency of a generator;

and determining the required power of the engine according to the peak power of the driving motor, the system efficiency of the generator and the output power of the power battery, wherein the required power of the engine and the peak power of the driving motor are in positive correlation, and the required power of the engine, the system efficiency of the driving motor and the system efficiency of the generator are in negative correlation.

In some embodiments of the present application, based on the above technical solution, adjusting the torque of the engine according to the required power of the driving motor includes:

acquiring the system efficiency of a driving motor and the system efficiency of a generator;

determining the required power of the engine according to the required power of the driving motor, the system efficiency of the driving motor and the system efficiency of the generator;

and adjusting the torque of the engine according to the required power of the engine.

In some embodiments of the present application, based on the above technical solutions, the driving mode switching condition includes that a torque jointly driven by the driving motor and the engine is larger than a torque separately driven by the driving motor.

In some embodiments of the present application, based on the above technical solutions, switching a range extending mode in which a driving mode of the hybrid vehicle is driven by the driving motor alone to a series-parallel mode in which the driving motor and the engine are driven together includes:

reducing the torque of the engine and obtaining the rotating speed of the engine;

when the rotating speed of the engine and the rotating speed of the wheel end of the hybrid electric vehicle meet preset conditions, switching a driving mode of the hybrid electric vehicle from a range-extending mode of independently driving the driving motor to a series-parallel mode of jointly driving the driving motor and the engine.

In some embodiments of the present application, based on the above technical solutions, before adjusting the torque of the engine according to the required power of the driving motor, the method further includes:

acquiring the speed and the wheel end required torque of the hybrid electric vehicle;

and determining the required power of the driving motor according to the vehicle speed and the wheel end required torque, wherein the required power of the driving motor is in positive correlation with the vehicle speed and the wheel end required torque.

In some embodiments of the present application, based on the above technical solutions, obtaining a vehicle speed and a wheel end required torque of the hybrid vehicle includes:

acquiring the speed of the hybrid electric vehicle according to a speed sensor of the hybrid electric vehicle;

and acquiring the wheel end required torque of the hybrid electric vehicle according to the depth of the accelerator pedal of the hybrid electric vehicle.

According to an aspect of the embodiments of the present application, there is provided a hybrid vehicle including: and the whole vehicle controller is used for realizing the driving method of the hybrid electric vehicle.

In the technical scheme provided by the embodiment of the application, when the hybrid electric vehicle accelerates, the target rotating speed of the engine is determined according to the battery charge state of the power battery, and the target rotating speed is lower than the maximum rotating speed of the engine; when the rotating speed of the engine reaches the target rotating speed, maintaining the rotating speed of the engine unchanged, and adjusting the torque of the engine according to the required power of the driving motor; when the driving mode switching condition is met, the range extending mode of the driving mode of the hybrid electric vehicle, which is independently driven by the driving motor, is switched to the series-parallel mode of the driving motor and the engine. According to the method and the device for controlling the target rotating speed of the hybrid electric vehicle, the difference between the rotating speed of the engine and the rotating speed of the wheel end can be reduced, and the switching speed of the driving mode of the hybrid electric vehicle is improved.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application.

Drawings

The accompanying drawings, which are incorporated in and constitute a part of this specification, illustrate embodiments consistent with the application and together with the description, serve to explain the principles of the application. It is apparent that the drawings in the following description are only some embodiments of the present application, and that other drawings may be obtained from these drawings without inventive effort for a person of ordinary skill in the art.

Fig. 1 shows a schematic diagram of a power system of a hybrid vehicle.

Fig. 2 shows a graph of battery output power change from a range-extending mode to a series-parallel mode in the related art of the present application.

Fig. 3 shows a flowchart of a driving method of the hybrid vehicle in one embodiment of the present application.

FIG. 4 illustrates a flow chart for determining a target speed of an engine in one embodiment of the present application.

Fig. 5 shows an external characteristic diagram of an embodiment of the present application in an application scenario.

FIG. 6 illustrates a flow chart for adjusting engine torque in one embodiment of the present application.

Fig. 7 shows a flow chart of switching drive modes in one embodiment of the present application.

Fig. 8 shows a schematic diagram of the change of the engine speed of the hybrid electric vehicle in one application scenario according to the embodiment of the present application.

Fig. 9 shows a block diagram of the overall vehicle controller in one embodiment of the present application.

Fig. 10 shows a schematic structural diagram of a hybrid vehicle in one embodiment of the present application.

Detailed Description

Example embodiments will now be described more fully with reference to the accompanying drawings. However, the exemplary embodiments may be embodied in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the example embodiments to those skilled in the art.

Furthermore, the described features, structures, or characteristics may be combined in any suitable manner in one or more embodiments. In the following description, numerous specific details are provided to give a thorough understanding of embodiments of the present application. One skilled in the relevant art will recognize, however, that the aspects of the application can be practiced without one or more of the specific details, or with other methods, components, devices, steps, etc. In other instances, well-known methods, devices, implementations, or operations are not shown or described in detail to avoid obscuring aspects of the application.

In the present embodiment, the term "module" or "unit" refers to a computer program or a part of a computer program having a predetermined function, and works together with other relevant parts to achieve a predetermined object, and may be implemented in whole or in part by using software, hardware (such as a processing circuit or a memory), or a combination thereof. Also, a processor (or multiple processors or memories) may be used to implement one or more modules or units. Furthermore, each module or unit may be part of an overall module or unit that incorporates the functionality of the module or unit.

The block diagrams depicted in the figures are merely functional entities and do not necessarily correspond to physically separate entities. That is, the functional entities may be implemented in software, or in one or more hardware modules or integrated circuits, or in different networks and/or processor devices and/or microcontroller devices.

The flow diagrams depicted in the figures are exemplary only, and do not necessarily include all of the elements and operations/steps, nor must they be performed in the order described. For example, some operations/steps may be decomposed, and some operations/steps may be combined or partially combined, so that the order of actual execution may be changed according to actual situations.

In the hundred kilometers test process of the hybrid electric vehicle, the whole vehicle controller (Vehicle Control Unit, VCU) can select a mode with the largest torque at the wheel end of the whole vehicle to operate, and in the front accelerating stage, the range increasing mode can only be selected because the rotating speed condition of the engine for directly driving the wheels is not reached (the rotating speed of the direct-drive engine is too low at the moment, the efficiency is very low), and after the condition of direct drive is met, if the torque at the wheel end of the engine for directly driving the vehicle is larger than the torque at the wheel end of the range increasing mode (namely, the series mode), at the moment, the VCU can control the vehicle to enter the series-parallel mode (namely, the parallel mode). In series-parallel mode, the engine may drive the wheel end directly while the battery may provide power to the drive motor and then drive the wheel end.

In the range-extending mode, the engine speed is decoupled from the wheel end; in the process of switching the parallel mode in series, the engine needs to adjust the rotating speed to be coupled with the wheel end so as to enter the parallel mode. The speed of the vehicle in and out is related to the battery power. Therefore, selecting different engine speeds in the range-extending mode has an effect on the NVH characteristics (noise, vibration and harshness, i.e., noise, vibration, harshness) of the vehicle and the speed of serial-parallel switching, and how to consider the switching speed and the NVH characteristics is a key technical problem.

Fig. 1 shows a schematic diagram of a power system of a hybrid vehicle. As shown in fig. 1, the power system of the hybrid vehicle includes an engine 101, a generator 102, a power battery 103, and a drive motor 104. The power coupling mode of the hybrid electric vehicle comprises two modes of electric coupling and electromechanical coupling.

In the electric coupling mode, i.e., the series mode, the engine 101 generates electric power by the generator 102, generating a first drive current. The power battery 103 outputs a second driving current. The two work simultaneously, after the first driving current and the second driving current are adjusted by the coupling device, the electric energy is supplied to the driving motor 104 together, and then the driving motor 104 supplies driving force to the wheels 105.

In an electromechanical coupling mode, such as a conventional parallel mode, the engine 101 directly drives the wheels 105 through the gearbox. At the same time, the electric power of the power battery 103 reaches the driving motor 104, and the driving motor 104 drives the wheels 105, and both can be physically connected with the driving device of the vehicle, and simultaneously apply the power for moving the vehicle.

In the related art of the present application, the range-extending mode preferentially increases the engine speed to the maximum speed at the time of full throttle, and the engine outputs the maximum power.

As shown in fig. 2, in the range-increasing mode, the battery outputs power P according to the demand of the motor _BAT ＝P _MOTOR -P _ICE . Wherein P is _BAT For the output power of the battery, P _MOTOR To drive the motor to power demand, P _ICE Is the power demand of the engine.

In the initial stage, the engine has redundant power to charge the battery due to low speed, and the battery outputs power P _BAT Is negative. After the vehicle speed rises to a certain degree, the battery output power P _BAT Positive values.

In the related art of the present application, in the range-extending mode, the engine speed is directly increased to the maximum speed, resulting in poor NVH performance. When the range-extending mode is switched to the series-parallel mode, the engine speed is switched from high speed to low speed, and the parallel switching time is longer due to the high speed of the series engine, so that the acceleration performance of the automobile is affected.

Fig. 3 shows a flowchart of a driving method of the hybrid vehicle in one embodiment of the present application. As shown in fig. 3, the driving method of the hybrid vehicle includes the following steps S310 to S330.

S310: when the hybrid electric vehicle accelerates, a target rotational speed of the engine is determined according to a battery state of charge of the power battery, the target rotational speed being lower than a maximum rotational speed of the engine.

S320: when the rotation speed of the engine reaches the target rotation speed, the rotation speed of the engine is maintained unchanged, and the torque of the engine is adjusted according to the required power of the driving motor.

S330: when the driving mode switching condition is met, the range extending mode of the driving mode of the hybrid electric vehicle, which is independently driven by the driving motor, is switched to the series-parallel mode of the driving motor and the engine.

According to the method and the device for controlling the target rotating speed of the hybrid electric vehicle, the difference between the rotating speed of the engine and the rotating speed of the wheel end can be reduced, and the switching speed of the driving mode of the hybrid electric vehicle is improved.

FIG. 4 illustrates a flow chart for determining a target speed of an engine in one embodiment of the present application. As shown in fig. 4, on the basis of the above embodiment, determining the target rotation speed of the engine according to the battery state of charge of the power battery in step S310 may include steps S311 to S313 as follows.

S311: and determining the output power of the power battery according to the battery charge state of the power battery.

The State of Charge (SOC), which may also be referred to as the remaining Charge of the power battery, represents the ratio of the remaining Charge of the power battery to the fully charged Charge, typically a percentage. Soc=0, indicating that the power battery is fully discharged; when soc=1, it indicates that the power battery is fully charged. SOC is a value estimated by a set of algorithm models established by comparing the collected mass data with the actual battery data. The higher the estimation accuracy of the SOC is, the longer the discharging time of the battery with the same capacity is, so that the electric automobile has more frequent endurance mileage. High accuracy SOC estimation may maximize the performance of the power cell.

The output power of the power battery and the remaining power of the battery are mutually influenced. Generally, the larger the remaining power, the larger the output power; the smaller the remaining power, the smaller the output power. The output power of the power battery is also affected by the voltage and the point flow; the higher the battery voltage, the greater the output power; the higher the battery current, the greater the output power.

S312: and determining the required power of the engine according to the output power of the power battery, wherein the required power of the engine and the output power of the power battery are in negative correlation.

In one embodiment of the present application, determining the required power of the engine according to the output power of the power battery may further include: obtaining peak power of a driving motor, system efficiency of the driving motor and system efficiency of a generator; and determining the required power of the engine according to the peak power of the driving motor, the system efficiency of the generator and the output power of the power battery, wherein the required power of the engine and the peak power of the driving motor are in positive correlation, and the required power of the engine and the system efficiency of the driving motor and the system efficiency of the generator are in negative correlation. According to the embodiment of the application, the required power of the engine is corrected according to the system efficiency of the driving motor and the system efficiency of the generator, and the accuracy of engine power control can be improved.

In one embodiment of the present application, the required power of the engine may be determined according to the following formula.

P _ICE ＝(P _{MOTOR_MAX} /η _MOTOR -P _BAT )/η _GE

Wherein P is _ICE For the power demand of the engine, P _{MOTOR_MAX} To drive peak power of motor, P _BAT Is the output power of the power battery, eta _MOTOR For system efficiency of driving motor, eta _GE Is an electric generatorIs a system efficiency of (a).

S313: a target rotational speed of the engine is determined based on the demanded power of the engine.

According to the method and the device for controlling the engine speed, the output power of the power battery is determined according to the battery charge state of the power battery, and then the target speed of the engine is determined according to the power relation among the engine, the driving motor and the generator, so that the engine speed can be accurately controlled below the maximum speed, the difference between the engine speed and the wheel end speed can be effectively reduced, and the switching speed of the driving mode of the hybrid electric vehicle is improved.

In one embodiment of the present application, determining the target rotational speed of the engine according to the required power of the engine may further include: acquiring an external characteristic curve of an engine; and inquiring an external characteristic curve according to the required power of the engine to obtain the target rotating speed of the engine.

The engine external characteristic curve refers to a curve of the power or torque measured at the time of full load of the engine as a function of the rotational speed. By querying the engine external characteristic, the engine target rotation speed corresponding to the required power of the engine can be obtained.

According to the method and the device for controlling the engine, the engine external characteristic curve which is mapped in advance is utilized, and the engine external characteristic curve can be quickly queried to obtain the engine target speed corresponding to the engine required power when the hybrid electric vehicle accelerates, so that the engine control time delay can be reduced, and the switching efficiency of the driving mode can be improved.

Fig. 5 shows an external characteristic diagram of an embodiment of the present application in an application scenario. As shown in fig. 5, according to the power of the power battery under different SOCs, the embodiment of the present application may obtain the rotational speed of the engine under the SOC, that is, the rotational speed corresponding to the engine power external characteristic curve. Therefore, the method can be used for controlling the engine speed in a real vehicle, and the NVH performance is improved.

The power of the power battery under different SOC is matched with different engine speeds, so that the time for series switching and parallel connection can be minimized, the switching process can be completed as soon as possible, and the power performance of the whole vehicle is improved.

FIG. 6 illustrates a flow chart for adjusting engine torque in one embodiment of the present application. As shown in fig. 6, on the basis of the above embodiment, adjusting the torque of the engine according to the required power of the driving motor in step S320 may include the following steps S321 to S323.

S321: the system efficiency of the drive motor and the system efficiency of the generator are obtained.

S322: and determining the required power of the engine according to the required power of the driving motor, the system efficiency of the driving motor and the system efficiency of the generator.

S323: the torque of the engine is adjusted according to the power demand of the engine.

According to the embodiment of the application, the required power of the engine is corrected according to the system efficiency of the driving motor and the system efficiency of the generator, the torque of the engine is further adjusted according to the required power of the engine, the accuracy of engine torque adjustment can be improved, and the reliability of engine speed control is further improved.

In one embodiment of the present application, the torque of the engine may be adjusted as follows.

P _ICE ＝(P _{MOTOR_REAL} /η _MOTOR -P _BAT )/η _GE

T _ICE ＝P _ICE ×9549

Wherein P is _ICE For the power demand of the engine, P _{MOTOR_REAL} To drive the motor to power demand, P _BAT Is the output power of the power battery, eta _MOTOR For system efficiency of driving motor, eta _GE T is the system efficiency of the generator _ICE Is the torque of the engine.

In one embodiment of the present application, the drive mode switching condition includes that the torque jointly driven by the drive motor and the engine is greater than the torque solely driven by the drive motor. According to the embodiment of the application, the driving mode switching condition is controlled, so that the driving mode of the hybrid electric vehicle can be switched when the torque jointly driven by the driving motor and the engine is larger than the torque independently driven by the driving motor, on one hand, the accuracy of switching time can be improved, on the other hand, the loss of torque output can be reduced, and the energy consumption of vehicle control is saved.

Fig. 7 shows a flow chart of switching drive modes in one embodiment of the present application. As shown in fig. 7, on the basis of the above embodiment, the range extending mode in which the drive mode of the hybrid vehicle is driven by the drive motor alone in step S330 is switched to the series-parallel mode in which the drive motor and the engine are driven together, including steps S331 to S332 as follows.

S331: the torque of the engine is reduced and the rotational speed of the engine is obtained.

S332: when the rotating speed of the engine and the rotating speed of the wheel end of the hybrid electric vehicle meet preset conditions, switching a range extending mode of a driving mode of the hybrid electric vehicle, which is independently driven by the driving motor, to a series-parallel mode of the driving motor and the engine.

The preset conditions may be the same, or the rotational speeds differ by no more than a set threshold. When the driving mode switching condition is met, the embodiment of the application precisely controls the switching time point of the driving mode according to the relation between the engine rotating speed and the wheel end rotating speed, and can switch the range-increasing mode of the driving mode of the hybrid electric vehicle, which is independently driven by the driving motor, to the series-parallel mode which is jointly driven by the driving motor and the engine when the engine rotating speed is close to the wheel end rotating speed of the vehicle by reducing the engine torque and acquiring the engine rotating speed, so that the success rate of mode switching can be improved, and the problem of failure of mode switching caused by overlarge rotating speed difference is avoided.

In one embodiment of the present application, the vehicle speed and the wheel end required torque of the hybrid vehicle may be obtained before the torque of the engine is adjusted according to the required power of the driving motor; and determining the required power of the driving motor according to the vehicle speed and the wheel end required torque, wherein the required power of the driving motor is in positive correlation with the vehicle speed and the wheel end required torque. According to the method and the device for determining the power demand of the driving motor, the required power of the driving motor can be determined according to the vehicle speed and the required torque of the wheel end by acquiring the vehicle speed and the required torque of the wheel end of the vehicle, the required power of the driving motor is determined according to the real running state of the vehicle, the accuracy of power calculation can be improved, and the reliability of mode switching can be improved.

In one embodiment of the present application, obtaining the vehicle speed and the wheel end required torque of the hybrid vehicle may further include: acquiring the speed of the hybrid electric vehicle according to a speed sensor of the hybrid electric vehicle; and obtaining the wheel end required torque of the hybrid electric vehicle according to the depth of the accelerator pedal of the hybrid electric vehicle. According to the embodiment of the application, the speed sensor and the accelerator pedal depth of the vehicle are utilized to determine the speed of the vehicle and the required torque of the wheel end, the real running state of the vehicle can be rapidly and conveniently obtained, and the mode switching efficiency is improved.

Fig. 8 shows a schematic diagram of the change of the engine speed of the hybrid electric vehicle in one application scenario according to the embodiment of the present application. As shown in fig. 8, the acceleration process of the hybrid vehicle may include four stages as follows.

The first stage: in the initial stage of full accelerator acceleration, a wheel end transmits a torque demand, a complete Vehicle Controller (VCU) responds, a signal is transmitted to a motor controller (IPU), a driving motor responds to the maximum torque, at the moment, the power required by an engine and the target demand of the rotating speed of the engine are calculated according to the peak power of the driving motor and the power of a battery pack under the current SOC, and the rotating speed of the engine is increased from 0 to the target rotating speed n _ICE . The above values are all offline calibration values, as shown in fig. 5, and are rotational speed values corresponding to different SOCs, and can be obtained by looking up a table in a real vehicle according to offline.

And a second stage: after the engine speed is increased to the target speed, maintaining the target speed unchanged, and calculating the engine demand power P according to the current motor demand power _ICE ＝(P _{MOTOR_REAL} /η _MOTOR -P _BAT )/η _GE And calculates the required output torque T of the engine _ICE ＝P _ICE X 9549. At this time, the first stage and the second stage are both in extended range mode.

And a third stage: at the moment, the VCU judges that the torque of the series-parallel mode is larger than that of the range-extending mode, the engine reduces the torque, and the rotation speed of the engine is reduced due to the counter-drag torque and the rotation inertia of the generator. When the speed of the engine is close to the speed of the wheel end, the clutch is engaged, and the speed difference of series-parallel switching is smaller than that of the prior scheme because the speed of the engine is controlled at a lower point in the range-increasing mode, so that the switching process is faster than that of the prior scheme.

Fourth stage: the clutch is combined, a series-parallel mode is entered, and the engine and the driving motor jointly drive wheels.

Based on the description of the application scene, in the scheme provided by the embodiment of the application, the rotation speed of the engine connected in series is controlled under different vehicle speeds, and different rotation speeds are selected according to different SOCs, so that the whole vehicle can obtain good NVH performance, acceleration performance can be ensured, comfort is improved, user experience of the hybrid electric vehicle is improved, and meanwhile, the scheme provided by the embodiment of the application has the advantages of high convenience, stability and reliability.

It should be noted that although the steps of the methods in the present application are depicted in the accompanying drawings in a particular order, this does not require or imply that the steps must be performed in that particular order, or that all illustrated steps be performed, to achieve desirable results. Additionally or alternatively, certain steps may be omitted, multiple steps combined into one step to perform, and/or one step decomposed into multiple steps to perform, etc.

The embodiment of the application also provides a hybrid electric vehicle, which comprises a whole vehicle controller, wherein the whole vehicle controller is used for realizing the driving method of the hybrid electric vehicle.

Fig. 9 shows a block diagram of the overall vehicle controller in one embodiment of the present application. As shown in fig. 9, the vehicle controller 900 may include:

a speed determination module 910 configured to determine a target speed of an engine from a battery state of charge of a power battery when a hybrid vehicle is accelerating, the target speed being lower than a maximum speed of the engine;

a torque adjustment module 920 configured to maintain the rotational speed of the engine when the rotational speed of the engine reaches the target rotational speed, and adjust the torque of the engine according to the required power of the driving motor;

the mode switching module 930 is configured to switch the range-extending mode of the hybrid vehicle, in which the driving motor alone drives the hybrid vehicle, to the series-parallel mode of the hybrid vehicle, in which the driving motor and the engine are driven together, when the driving mode switching condition is satisfied.

In some embodiments of the present application, based on the above technical solutions, the rotation speed determination module 910 may be further configured to: determining the output power of a power battery according to the battery charge state of the power battery; determining the required power of the engine according to the output power of the power battery, wherein the required power of the engine and the output power of the power battery are in a negative correlation; and determining the target rotating speed of the engine according to the required power of the engine.

In some embodiments of the present application, based on the above technical solutions, the rotation speed determination module 910 may be further configured to: acquiring an external characteristic curve of the engine; and inquiring the external characteristic curve according to the required power of the engine to obtain the target rotating speed of the engine.

In some embodiments of the present application, based on the above technical solutions, the rotation speed determination module 910 may be further configured to: obtaining peak power of the driving motor, system efficiency of the driving motor and system efficiency of a generator; and determining the required power of the engine according to the peak power of the driving motor, the system efficiency of the generator and the output power of the power battery, wherein the required power of the engine and the peak power of the driving motor are in positive correlation, and the required power of the engine, the system efficiency of the driving motor and the system efficiency of the generator are in negative correlation.

In some embodiments of the present application, based on the above technical solutions, the torque adjustment module 920 may be further configured to: acquiring the system efficiency of a driving motor and the system efficiency of a generator; determining the required power of the engine according to the required power of the driving motor, the system efficiency of the driving motor and the system efficiency of the generator; and adjusting the torque of the engine according to the required power of the engine.

In some embodiments of the present application, based on the above technical solutions, the mode switching module 930 may be further configured to: reducing the torque of the engine and obtaining the rotating speed of the engine; when the rotating speed of the engine and the rotating speed of the wheel end of the hybrid electric vehicle meet preset conditions, switching a driving mode of the hybrid electric vehicle from a range-extending mode of independently driving the driving motor to a series-parallel mode of jointly driving the driving motor and the engine.

In some embodiments of the present application, based on the above technical solutions, the whole vehicle controller further includes:

the required power determining module is configured to acquire the speed and the wheel end required torque of the hybrid electric vehicle; and determining the required power of the driving motor according to the vehicle speed and the wheel end required torque, wherein the required power of the driving motor is in positive correlation with the vehicle speed and the wheel end required torque.

In some embodiments of the present application, based on the above technical solutions, the required power determining module may be further configured to: acquiring the speed of the hybrid electric vehicle according to a speed sensor of the hybrid electric vehicle; and acquiring the wheel end required torque of the hybrid electric vehicle according to the depth of the accelerator pedal of the hybrid electric vehicle.

Fig. 10 shows a schematic structural diagram of a hybrid vehicle in one embodiment of the present application. As shown in fig. 10, the hybrid vehicle in the embodiment of the present application includes a vehicle controller 1000, and the vehicle controller 1000 may include one or more of the following components: a processor 1001, memory 1002, and one or more application programs. Wherein one or more application programs may be stored in the memory 1002 and configured to be executed by the one or more processors 1001, the one or more application programs configured to perform the driving method of the hybrid vehicle as described in the foregoing method embodiments.

The processor 1001 may include one or more processing cores. The processor 1001 connects various parts of the entire hybrid vehicle using various interfaces and lines, performs various functions of the hybrid vehicle and processes data by running or executing instructions, programs, code sets, or instruction sets stored in the memory 1002, and calling data stored in the memory 1002. Alternatively, the processor 1001 may be implemented in at least one hardware form of digital signal processing (Digital Signal Processing, DSP), field-Programmable gate array (FPGA), programmable Logic Array (PLA). The processor 1001 may integrate one or a combination of several of a central processing unit (CentralProcessing Unit, CPU), an image processor (Graphics Processing Unit, GPU), and a modem, etc. The CPU mainly processes an operating system, a user interface, an application program and the like; the GPU is used for being responsible for rendering and drawing of display content; the modem is used to handle wireless communications. It will be appreciated that the modem may not be integrated into the processor 1001 and may be implemented solely by a single communication chip.

The Memory 1002 may include a random access Memory (Random Access Memory, RAM) or a Read Only Memory (Read Only Memory). Memory 1002 may be used to store instructions, programs, code, sets of codes, or instruction sets. The memory 1002 may include a stored program area and a stored data area, wherein the stored program area may store instructions for implementing an operating system, instructions for implementing at least one function, instructions for implementing the various method embodiments described above, and the like. The stored data area may also store data created by the hybrid vehicle during use.

In particular, according to embodiments of the present application, the processes described in the various method flowcharts may be implemented as computer software programs. For example, embodiments of the present application include a computer program product comprising a computer program embodied on a computer readable medium, the computer program comprising program code for performing the method shown in the flowcharts. In such embodiments, the computer program may be downloaded and installed from a network via a communication portion, and/or installed from a removable medium. The computer program, when executed by a processor, performs the various functions defined in the system of the present application.

It should be noted that, the computer readable medium shown in the embodiments of the present application may be a computer readable signal medium or a computer readable storage medium, or any combination of the two. The computer readable storage medium can be, for example, but not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, apparatus, or device, or a combination of any of the foregoing. More specific examples of the computer-readable storage medium may include, but are not limited to: an electrical connection having one or more wires, a portable computer diskette, a hard disk, a Random Access Memory (RAM), a read-Only Memory (ROM), an erasable programmable read-Only Memory (Erasable Programmable Read Only Memory, EPROM), flash Memory, an optical fiber, a portable compact disc read-Only Memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing. In the context of this document, a computer readable storage medium may be any tangible medium that can contain, or store a program for use by or in connection with an instruction execution system, apparatus, or device. In the present application, however, a computer-readable signal medium may include a data signal that propagates in baseband or as part of a carrier wave, with the computer-readable program code embodied therein. Such a propagated data signal may take any of a variety of forms, including, but not limited to, electro-magnetic, optical, or any suitable combination of the foregoing. A computer readable signal medium may also be any computer readable medium that is not a computer readable storage medium and that can communicate, propagate, or transport a program for use by or in connection with an instruction execution system, apparatus, or device. Program code embodied on a computer readable medium may be transmitted using any appropriate medium, including but not limited to: wireless, wired, etc., or any suitable combination of the foregoing.

The flowcharts and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to various embodiments of the present application. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that, in some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. It will also be noted that each block of the block diagrams or flowchart illustration, and combinations of blocks in the block diagrams or flowchart illustration, can be implemented by special purpose hardware-based systems which perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.

It should be noted that although in the above detailed description several modules or units of a device for action execution are mentioned, such a division is not mandatory. Indeed, the features and functions of two or more modules or units described above may be embodied in one module or unit, in accordance with embodiments of the present application. Conversely, the features and functions of one module or unit described above may be further divided into a plurality of modules or units to be embodied.

From the above description of embodiments, those skilled in the art will readily appreciate that the example embodiments described herein may be implemented in software, or may be implemented in software in combination with the necessary hardware. Thus, the technical solution according to the embodiments of the present application may be embodied in the form of a software product, which may be stored in a non-volatile storage medium (may be a CD-ROM, a usb disk, a mobile hard disk, etc.) or on a network, and includes several instructions to cause a computing device (may be a personal computer, a server, a touch terminal, or a network device, etc.) to perform the method according to the embodiments of the present application.

Other embodiments of the present application will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the application following, in general, the principles of the application and including such departures from the present disclosure as come within known or customary practice within the art to which the application pertains.

It is to be understood that the present application is not limited to the precise arrangements and instrumentalities shown in the drawings, which have been described above, and that various modifications and changes may be effected without departing from the scope thereof. The scope of the application is limited only by the appended claims.

Claims

1. A driving method of a hybrid vehicle, comprising:

2. The driving method of a hybrid vehicle according to claim 1, wherein determining the target rotation speed of the engine based on the battery state of charge of the power battery includes:

3. The driving method of the hybrid vehicle according to claim 2, characterized in that determining the target rotation speed of the engine from the required power of the engine includes:

acquiring an external characteristic curve of the engine;

4. The driving method of the hybrid vehicle according to claim 2, characterized in that determining the required power of the engine from the output power of the power battery includes:

5. The driving method of a hybrid vehicle according to claim 1, wherein adjusting the torque of the engine according to the required power of the driving motor includes:

6. The driving method of the hybrid vehicle according to claim 1, wherein the driving mode switching condition includes that a torque jointly driven by the driving motor and the engine is larger than a torque separately driven by the driving motor.

7. The driving method of the hybrid vehicle according to claim 6, characterized in that switching the range-extending mode in which the driving mode of the hybrid vehicle is driven by the driving motor alone to the series-parallel mode in which the driving motor and the engine are driven together, includes:

8. The driving method of a hybrid vehicle according to any one of claims 1 to 7, characterized in that before adjusting the torque of the engine according to the required power of the driving motor, the method further comprises:

9. The driving method of a hybrid vehicle according to claim 8, wherein obtaining a vehicle speed and a wheel end demand torque of the hybrid vehicle includes:

10. A hybrid vehicle characterized by comprising:

an overall vehicle controller for implementing the driving method of a hybrid vehicle according to any one of claims 1 to 9.