Hybrid vehicle and driving method therefor

Abstract

The present application relates to the technical field of new energy vehicles, and in particular to a hybrid vehicle and a driving method therefor. The driving method for the hybrid vehicle comprises: when the hybrid vehicle accelerates, determining a target rotation speed of an engine on the basis of the state of charge of a power battery, the target rotation speed being lower than the maximum rotation speed of the engine; when the rotation speed of the engine reaches the target rotation speed, maintaining the rotation speed of the engine unchanged, and adjusting the torque of the engine on the basis of the required power of a driving motor; and when a driving mode switching condition is satisfied, switching the driving mode of the hybrid vehicle from an extended range mode in which driving is performed independently by the driving motor to a series-parallel mode in which driving is performed jointly by the driving motor and the engine. The present application can improve the switching speed of the driving mode of the hybrid vehicle.

Description

Hybrid electric vehicle and driving method thereof

[0001] This application claims priority to the Chinese patent application filed with the China Patent Office on January 18, 2024, with application number 202410073380.5 and invention name “Hybrid vehicle and driving method thereof”, the entire contents of which are incorporated herein by reference. Technical Field

[0002] The present application belongs to the field of new energy vehicle technology, and specifically relates to a hybrid vehicle and a driving method thereof. Background Art

[0003] A hybrid vehicle is a car that can be driven by both gasoline and electricity. During operation, a hybrid vehicle can switch between different drive modes based on actual needs. However, the significant difference between engine speed and wheel speed during drive mode switching can result in slow switching. Summary of the Invention

[0004] The present application provides a hybrid vehicle and a driving method thereof, aiming to increase the switching speed of the driving mode of the hybrid vehicle.

[0005] Other features and advantages of the present application will become apparent from the following detailed description, or may be learned in part by practice of the present application.

[0006] According to one aspect of an embodiment of the present application, a driving method for a hybrid vehicle is provided, the method comprising:

[0007] When the hybrid vehicle accelerates, determining a target speed of the engine according to the battery state of charge of the power battery, wherein the target speed is lower than the maximum speed of the engine;

[0008] When the speed of the engine reaches the target speed, the speed of the engine is maintained unchanged, and the torque of the engine is adjusted according to the required power of the drive motor;

[0009] When a driving mode switching condition is met, the driving mode of the hybrid vehicle is switched from the range-extending mode in which the driving motor is driven alone to the parallel-parallel mode in which the driving motor and the engine are driven together.

[0010] In some embodiments of the present application, based on the above technical solution, determining the target speed of the engine according to the battery state of charge of the power battery includes:

[0011] determining the output power of the power battery according to the battery state of charge of the power battery;

[0012] determining the required power of the engine according to the output power of the power battery, wherein the required power of the engine is negatively correlated with the output power of the power battery;

[0013] The target speed of the engine is determined according to the required power of the engine.

[0014] In some embodiments of the present application, based on the above technical solution, determining the target speed of the engine according to the required power of the engine includes:

[0015] Obtaining an external characteristic curve of the engine;

[0016] The external characteristic curve is queried according to the required power of the engine to obtain the target speed of the engine.

[0017] In some embodiments of the present application, based on the above technical solution, determining the required power of the engine according to the output power of the power battery includes:

[0018] Obtaining the peak power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator;

[0019] The required power of the engine is determined based on the peak power of the drive motor, the system efficiency of the drive motor, the system efficiency of the generator and the output power of the power battery. The required power of the engine is positively correlated with the peak power of the drive motor, and negatively correlated with the system efficiency of the drive motor and the system efficiency of the generator.

[0020] 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 drive motor includes:

[0021] Obtain the system efficiency of the drive motor and the system efficiency of the generator;

[0022] determining the required power of the engine according to the required power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator;

[0023] The torque of the engine is adjusted according to the required power of the engine.

[0024] In some embodiments of the present application, based on the above technical solution, the driving mode switching condition includes that the torque jointly driven by the driving motor and the engine is greater than the torque driven by the driving motor alone.

[0025] In some embodiments of the present application, based on the above technical solution, the driving mode of the hybrid vehicle is switched from the extended-range mode in which the drive motor is driven alone to the parallel-parallel mode in which the drive motor and the engine are driven together, including:

[0026] reducing the torque of the engine and obtaining the speed of the engine;

[0027] When the engine speed and the wheel end speed of the hybrid vehicle meet preset conditions, the driving mode of the hybrid vehicle is switched from the extended-range mode driven by the drive motor alone to the parallel-parallel mode driven by the drive motor and the engine together.

[0028] In some embodiments of the present application, based on the above technical solution, before adjusting the torque of the engine according to the required power of the drive motor, the method further includes:

[0029] Obtaining the vehicle speed and wheel-end required torque of the hybrid vehicle;

[0030] The required power of the drive motor is determined according to the vehicle speed and the required wheel end torque, and the required power of the drive motor is positively correlated with the vehicle speed and the required wheel end torque.

[0031] In some embodiments of the present application, based on the above technical solution, obtaining the vehicle speed and wheel-end required torque of the hybrid vehicle includes:

[0032] acquiring a vehicle speed of the hybrid vehicle according to a vehicle speed sensor of the hybrid vehicle;

[0033] The wheel end required torque of the hybrid vehicle is obtained according to the accelerator pedal depth of the hybrid vehicle.

[0034] According to one aspect of an embodiment of the present application, a hybrid vehicle is provided, comprising: a vehicle controller for implementing the driving method of the hybrid vehicle as described in the above technical solution.

[0035] In the technical solution provided in the embodiments of this application, when a hybrid vehicle accelerates, the target engine speed is determined based on the power battery's state of charge, with the target speed being lower than the engine's maximum speed. When the engine speed reaches the target speed, the engine speed is maintained constant, and the engine torque is adjusted based on the required power of the drive motor. When the drive mode switching conditions are met, the hybrid vehicle's drive mode is switched from extended-range mode, where the drive motor alone drives, to parallel-parallel mode, where both the drive motor and the engine drive. By controlling the hybrid vehicle's target speed, the embodiments of this application can reduce the difference between the engine speed and the wheel-end speed, thereby increasing the speed of the hybrid vehicle's drive mode switching.

[0036] It should be understood that the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0037] The accompanying drawings are incorporated into and constitute a part of the specification, illustrate embodiments consistent with the present application, and together with the specification, are used to explain the principles of the present application. Obviously, the drawings described below are only some embodiments of the present application, and those skilled in the art can derive other drawings based on these drawings without inventive effort.

[0038] FIG1 shows a schematic diagram of a power system of a hybrid electric vehicle.

[0039] FIG2 shows a diagram showing the battery output power change when switching from the extended-range mode to the parallel-parallel mode in the related art of this application.

[0040] FIG3 shows a flow chart of a driving method for a hybrid vehicle in one embodiment of the present application.

[0041] FIG4 shows a flow chart for determining a target speed of an engine in one embodiment of the present application.

[0042] FIG5 is a schematic diagram showing an external characteristic curve of an embodiment of the present application in an application scenario.

[0043] FIG6 shows a flowchart of adjusting engine torque in one embodiment of the present application.

[0044] FIG7 shows a flow chart of switching driving modes in one embodiment of the present application.

[0045] FIG8 is a schematic diagram showing changes in engine speed when a hybrid vehicle accelerates in an application scenario according to an embodiment of the present application.

[0046] FIG9 shows a structural block diagram of a vehicle controller in one embodiment of the present application.

[0047] FIG10 shows a schematic structural diagram of a hybrid vehicle in one embodiment of the present application. DETAILED DESCRIPTION

[0048] Example embodiments will now be described more fully with reference to the accompanying drawings. However, example embodiments can be implemented in many forms and should not be construed as limited to the examples set forth herein; rather, these embodiments are provided so that this application will be thorough and complete and will fully convey the concepts of the example embodiments to those skilled in the art.

[0049] In addition, described feature, structure or characteristic can be combined in one or more embodiments in any suitable manner.In the following description, many specific details are provided so as to provide a full understanding of the embodiments of the present application. However, it will be appreciated by those skilled in the art that the technical scheme of the present application can be put into practice without one or more of the specific details, or other methods, components, devices, steps etc. can be adopted. In other cases, known methods, devices, implementations or operations are not shown or described in detail to avoid blurring the various aspects of the application.

[0050] In the embodiments of the present application, the term "module" or "unit" refers to a computer program or a part of a computer program that has a predetermined function and works together with other related parts to achieve a predetermined goal, and can be implemented in whole or in part by using software, hardware (such as processing circuits or memories) or a combination thereof. Similarly, a processor (or multiple processors or memories) can be used to implement one or more modules or units. In addition, each module or unit can be part of an overall module or unit that includes the function of the module or unit.

[0051] The block diagrams shown in the accompanying drawings are merely functional entities and do not necessarily correspond to physically separate entities. That is, these functional entities may be implemented in software, in one or more hardware modules or integrated circuits, or in different networks and / or processor devices and / or microcontroller devices.

[0052] The flowcharts shown in the accompanying drawings are for illustrative purposes only and do not necessarily include all contents and operations / steps, nor must they be executed in the order described. For example, some operations / steps may be decomposed, while others may be combined or partially combined. Therefore, the actual execution order may vary depending on the actual situation.

[0053] During the 100km / h test of a hybrid vehicle, the vehicle control unit (VCU) selects the mode with the maximum wheel-end torque for operation. In the early stages of acceleration, because the engine's speed conditions for directly driving the wheels are not met (the direct-drive engine speed is too low at this time, making the efficiency very low), only the extended-range mode can be selected. After the conditions for direct drive are met, if the engine's direct-drive wheel-end torque is greater than that of the extended-range mode (i.e., series mode), the VCU controls the vehicle to enter the series-parallel mode. In series-parallel mode, the engine can directly drive the wheels, while the battery can also provide power to the drive motor, which then drives the wheels.

[0054] In extended-range mode, the engine speed is decoupled from the wheels; when switching from series to parallel mode, the engine speed must be adjusted to couple with the wheels before entering parallel mode. The vehicle speed at which parallel operation is achieved is related to battery power. Therefore, selecting different engine speeds in extended-range mode affects both the vehicle's NVH (noise, vibration, and harshness) characteristics and the speed of series-parallel switching. Balancing switching speed and NVH characteristics is a key technical issue.

[0055] Figure 1 shows a schematic diagram of the power system of a hybrid electric vehicle. As shown in Figure 1, the power system of a hybrid electric vehicle includes an engine 101, a generator 102, a power battery 103, and a drive motor 104. The power coupling methods of a hybrid electric vehicle include electric-electrical coupling and electromechanical coupling.

[0056] In electric-electric coupling mode, or series mode, engine 101 generates electricity through generator 102, producing a first drive current. Power battery 103 outputs a second drive current. Both operate simultaneously, and after adjustment by the coupling device, the first and second drive currents jointly provide electrical energy to drive motor 104, which then provides driving force to wheels 105.

[0057] In an electromechanical coupling mode, such as the commonly used parallel mode, engine 101 directly drives wheels 105 through a gearbox. Simultaneously, power from power battery 103 reaches drive motor 104, which in turn drives wheels 105. Both physically connect to the vehicle's drive system and simultaneously provide the power to move the vehicle.

[0058] In the related art of the present application, the range-extending mode prioritizes increasing the engine speed to the maximum speed at full throttle, so that the engine outputs maximum power.

[0059] FIG2 shows a diagram showing the battery output power change when switching from the extended-range mode to the parallel-parallel mode in the related art of this application.

[0060] As shown in Figure 2, in the extended range mode, the battery outputs power P according to the needs of the motor. BAT =P MOTOR -P ICE Among them, P BAT is the output power of the battery, P MOTOR is the required power of the drive motor, P ICE The required power of the engine.

[0061] In the initial stage, due to the low vehicle speed, the engine has excess power to charge the battery. At this time, the battery output power P BAT When the vehicle speed increases to a certain level, the battery output power P BATIs a positive value.

[0062] In the related art of this application, in extended-range mode, the engine speed is directly increased to the maximum speed, resulting in poor NVH performance. When switching from extended-range mode to parallel hybrid mode, the engine speed switches from high to low speed. Due to the high speed of the series engine, the parallel switching time is long, affecting the vehicle's acceleration performance.

[0063] Figure 3 shows a flow chart of a method for driving a hybrid electric vehicle in one embodiment of the present application. As shown in Figure 3 , the method for driving a hybrid electric vehicle includes the following steps S310 to S330 .

[0064] S310: When the hybrid vehicle accelerates, a target engine speed is determined according to the battery state of charge of the power battery, and the target engine speed is lower than the maximum engine speed.

[0065] S320: When the engine speed reaches the target speed, the engine speed is maintained unchanged, and the engine torque is adjusted according to the required power of the drive motor.

[0066] S330: When a driving mode switching condition is met, the driving mode of the hybrid vehicle is switched from the range-extending mode in which the driving motor is driven alone to the parallel-parallel mode in which the driving motor and the engine are driven together.

[0067] The embodiment of the present application can reduce the difference between the engine speed and the wheel end speed by controlling the target speed of the hybrid vehicle, thereby increasing the switching speed of the hybrid vehicle's driving mode.

[0068] FIG4 shows a flow chart for determining the target engine speed in one embodiment of the present application. As shown in FIG4 , based on the above embodiment, determining the target engine speed based on the battery state of charge of the power battery in step S310 may include the following steps S311 to S313.

[0069] S311: Determine the output power of the power battery according to the battery state of charge of the power battery.

[0070] The battery state of charge (SOC), also known as the remaining capacity of the power battery, represents the ratio of the remaining capacity of the power battery to the fully charged capacity, usually as a percentage. When SOC = 0, it means that the power battery is fully discharged; when SOC = 1, it means that the power battery is fully charged. SOC is a value estimated by comparing a large amount of collected data with an algorithm model established by comparing the actual battery data. The higher the accuracy of the SOC estimation, the longer the discharge time of the battery with the same capacity, which can enable electric vehicles to have a longer driving range. High-precision SOC estimation can maximize the efficiency of the power battery.

[0071] The output power of a power battery is influenced by its remaining charge. Generally speaking, the greater the remaining charge, the greater the output power; the smaller the remaining charge, the smaller the output power. The output power of a power battery is also affected by voltage and current: higher voltages produce greater output power, while higher currents produce greater output power.

[0072] S312: Determine the required power of the engine according to the output power of the power battery. The required power of the engine is negatively correlated with the output power of the power battery.

[0073] In one embodiment of the present application, determining the required engine power based on the output power of the power battery may further include: obtaining the peak power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator; determining the required engine power based on the peak power of the drive motor, the system efficiency of the drive motor, the system efficiency of the generator, and the output power of the power battery, wherein the required engine power is positively correlated with the peak power of the drive motor, and negatively correlated with the system efficiency of the drive motor and the system efficiency of the generator. This embodiment of the present application corrects the required engine power based on the system efficiency of the drive motor and the system efficiency of the generator, thereby improving the accuracy of engine power control.

[0074] In one embodiment of the present application, the required power of the engine can be determined according to the following formula. ICE =(P MOTOR_MAX / η MOTOR -P BAT ) / η GE

[0075] Among them, P ICE is the engine's required power, P MOTOR_MAX is the peak power of the driving motor, P BAT is the output power of the power battery, η MOTOR is the system efficiency of the drive motor, η GE is the system efficiency of the generator.

[0076] S313: Determine the target engine speed according to the required engine power.

[0077] The embodiment of the present application determines the output power of the power battery according to the battery state of charge of the power battery, and then determines the target speed of the engine according to the power relationship between the engine, the drive motor and the generator. This can accurately control the engine speed below its maximum speed and effectively reduce the difference between the engine speed and the wheel end speed, thereby improving the switching speed of the hybrid vehicle's drive mode.

[0078] In one embodiment of the present application, determining the target speed of the engine according to the required power of the engine may further include: obtaining an external characteristic curve of the engine; and querying the external characteristic curve according to the required power of the engine to obtain the target speed of the engine.

[0079] The engine's external characteristic curve is a graph showing how power or torque changes with engine speed at full load. By querying the engine's external characteristic curve, you can determine the target engine speed corresponding to the engine's required power.

[0080] The embodiment of the present application utilizes a pre-mapped engine external characteristic curve, which can quickly query the engine external characteristic curve to obtain the engine target speed corresponding to the engine demand power when the hybrid vehicle accelerates, thereby reducing the engine control delay and improving the switching efficiency of the driving mode.

[0081] Figure 5 shows a schematic diagram of the external characteristic curve of an embodiment of the present application in an application scenario. As shown in Figure 5, the embodiment of the present application can calculate the engine speed at different SOCs based on the power of the power battery at that SOC, i.e., the speed corresponding to the engine power external characteristic curve. This method can be used in actual vehicles to control engine speed and improve NVH performance.

[0082] By matching the power of the power battery at different SOCs to different engine speeds, the time for switching from series to parallel can be minimized, thereby completing the switching process as quickly as possible and improving the power performance of the entire vehicle.

[0083] FIG6 shows a flow chart of adjusting the engine torque in one embodiment of the present application. As shown in FIG6 , based on the above embodiment, adjusting the engine torque according to the required power of the drive motor in step S320 may include the following steps S321 to S323.

[0084] S321: Obtaining the system efficiency of the drive motor and the system efficiency of the generator.

[0085] S322: Determine the required power of the engine according to the required power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator.

[0086] S323: Adjust the engine torque according to the required power of the engine.

[0087] The embodiment of the present application corrects the engine's required power according to the system efficiency of the drive motor and the system efficiency of the generator, and further adjusts the engine's torque according to the engine's required power, which can improve the accuracy of the engine's torque adjustment and thereby improve the reliability of the engine's speed control.

[0088] In one embodiment of the present application, the engine torque can be adjusted according to the following formula. ICE =(P MOTOR_REAL / η MOTOR -P BAT ) / η GE T ICE =P ICE ×9549

[0089] Among them, P ICE is the engine's required power, P MOTOR_REAL is the required power of the drive motor, P BAT is the output power of the power battery, η MOTOR is the system efficiency of the drive motor, η GE is the system efficiency of the generator, T ICE is the engine torque.

[0090] In one embodiment of the present application, the drive mode switching condition includes the torque generated by the combined drive motor and engine being greater than the torque generated by the drive motor alone. By controlling the drive mode switching condition, the present embodiment can switch the drive mode of the hybrid vehicle when the torque generated by the combined drive motor and engine is greater than the torque generated by the drive motor alone. This improves the accuracy of the switching timing and reduces torque output loss, thereby saving energy consumption for vehicle control.

[0091] FIG7 shows a flowchart for switching drive modes in one embodiment of the present application. As shown in FIG7 , based on the above embodiment, step S330 of switching the hybrid vehicle's drive mode from the extended-range mode (driven solely by the drive motor) to the parallel-parallel mode (driven jointly by the drive motor and the engine) includes the following steps S331 to S332.

[0092] S331: Reduce the engine torque and obtain the engine speed.

[0093] S332: When the engine speed and the wheel end speed of the hybrid vehicle meet preset conditions, the driving mode of the hybrid vehicle is switched from the extended-range mode driven solely by the drive motor to the parallel-parallel mode driven jointly by the drive motor and the engine.

[0094] The preset condition can be that the speeds are the same, or that the speed difference does not exceed a set threshold. While satisfying the drive mode switching conditions, embodiments of the present application also precisely control the drive mode switching timing based on the relationship between the engine speed and the wheel-end speed. By reducing engine torque and obtaining engine speed, the hybrid vehicle's drive mode can be switched from the extended-range mode (driven solely by the drive motor) to the parallel-parallel mode (driven jointly by the drive motor and the engine) when the engine speed approaches the vehicle's wheel-end speed. This improves the success rate of mode switching and avoids the problem of mode switching failure caused by excessive speed differences.

[0095] In one embodiment of the present application, before adjusting the engine torque based on the required power of the drive motor, the vehicle speed and wheel-end required torque of the hybrid vehicle can be obtained; the required power of the drive motor can be determined based on the vehicle speed and wheel-end required torque, and the required power of the drive motor is positively correlated with the vehicle speed and wheel-end required torque. By obtaining the vehicle speed and wheel-end required torque, the embodiment of the present application can determine the required power of the drive motor based on the vehicle speed and wheel-end required torque. By combining the determination of the required power of the drive motor with the actual driving state of the vehicle, the accuracy of power calculation can be improved, thereby improving the reliability of mode switching.

[0096] In one embodiment of the present application, obtaining the hybrid vehicle's speed and wheel-end torque requirement may further include: obtaining the hybrid vehicle's speed based on the hybrid vehicle's speed sensor; and obtaining the hybrid vehicle's wheel-end torque requirement based on the hybrid vehicle's accelerator pedal depth. This embodiment of the present application utilizes the vehicle's own speed sensor and accelerator pedal depth to determine the vehicle's speed and wheel-end torque requirement, enabling quick and convenient acquisition of the vehicle's actual driving status and improving mode switching efficiency.

[0097] Figure 8 shows a schematic diagram of the change in engine speed when a hybrid vehicle accelerates in an application scenario according to an embodiment of the present application. As shown in Figure 8 , the acceleration process of a hybrid vehicle may include the following four stages.

[0098] Phase 1: In the initial stage of full throttle acceleration, the wheel end sends a torque demand, the vehicle controller (VCU) responds, sends a signal to the motor controller (IPU), and the drive motor responds with maximum torque. At this time, based on the peak power of the drive motor and the power of the battery pack at the current SOC, the required engine power and engine speed target demand are calculated, and the engine speed is increased from 0 to the target speed n ICE The above values ​​are all offline calibration values, as shown in Figure 5, which are the speed values ​​corresponding to different SOCs. They can be obtained by looking up the table offline in the actual vehicle.

[0099] Phase 2: After the engine speed reaches the target speed, the target speed is maintained unchanged, and the engine power requirement P is calculated based on the current motor power requirement. ICE =(P MOTOR_REAL / η MOTOR -P BAT ) / η GE , and calculate the required output torque T of the engine ICE =P ICE ×9549. At this time, both the first and second stages are in extended range mode.

[0100] Phase 3: At this point, the VCU determines that the torque in the hybrid mode is greater than that in the extended-range mode. The engine reduces its torque, and the engine speed drops due to the generator's counter-torque and rotational inertia. When the speed is close to the wheel-end speed, the clutch engages. Because the engine speed in the extended-range mode is controlled at a lower point in this application, the speed difference between series and parallel switching is smaller than that of existing solutions, resulting in a faster switching process.

[0101] Stage 4: The clutch engages, entering the hybrid mode, and the engine and drive motor jointly drive the wheels.

[0102] Based on the introduction of the above application scenarios, it can be seen that in the solution provided in the embodiment of the present application, by controlling the speed of the engine in series at different vehicle speeds and selecting different speeds according to different SOCs, the entire vehicle can obtain good NVH performance while ensuring acceleration performance, improving comfort, and improving the user experience of hybrid vehicles. At the same time, the solution provided in the embodiment of the present application has the advantages of high convenience, stability and reliability.

[0103] It should be noted that although the steps of the method of the present application are described in a specific order in the drawings, this does not require or imply that the steps must be performed in this specific order, or that all steps must be performed to achieve the desired results. Additionally or alternatively, some steps may be omitted, multiple steps may be combined into one step, and / or one step may be decomposed into multiple steps.

[0104] An embodiment of the present application further provides a hybrid electric vehicle, which includes a vehicle controller, and the vehicle controller is used to implement the driving method of the hybrid electric vehicle as described in the above embodiment.

[0105] Figure 9 shows a block diagram of a vehicle controller in one embodiment of the present application. As shown in Figure 9, the vehicle controller 900 may include:

[0106] A speed determination module 910 is configured to determine a target speed of the engine according to the battery state of charge of the power battery when the hybrid vehicle accelerates, wherein the target speed is lower than the maximum speed of the engine;

[0107] a torque adjustment module 920 configured to maintain the engine speed unchanged when the engine speed reaches the target speed, and adjust the engine torque according to the required power of the drive motor;

[0108] The mode switching module 930 is configured to switch the driving mode of the hybrid vehicle from the extended-range mode driven solely by the driving motor to the parallel-parallel mode driven jointly by the driving motor and the engine when a driving mode switching condition is met.

[0109] In some embodiments of the present application, based on the above technical solution, the speed determination module 910 can be further configured to: determine the output power of the power battery according to the battery state of charge of the power battery; determine the required power of the engine according to the output power of the power battery, and the required power of the engine is negatively correlated with the output power of the power battery; determine the target speed of the engine according to the required power of the engine.

[0110] In some embodiments of the present application, based on the above technical solution, the speed determination module 910 can be further configured to: obtain the external characteristic curve of the engine; query the external characteristic curve according to the required power of the engine to obtain the target speed of the engine.

[0111] In some embodiments of the present application, based on the above technical solution, the speed determination module 910 can be further configured to: obtain the peak power of the drive motor, the system efficiency of the drive motor and the system efficiency of the generator; determine the required power of the engine according to the peak power of the drive motor, the system efficiency of the drive motor, the system efficiency of the generator and the output power of the power battery, the required power of the engine is positively correlated with the peak power of the drive motor, and the required power of the engine is negatively correlated with the system efficiency of the drive motor and the system efficiency of the generator.

[0112] In some embodiments of the present application, based on the above technical solution, the torque adjustment module 920 can be further configured to: obtain the system efficiency of the drive motor and the system efficiency of the generator; determine the required power of the engine according to the required power of the drive motor, the system efficiency of the drive motor and the system efficiency of the generator; and adjust the torque of the engine according to the required power of the engine.

[0113] In some embodiments of the present application, based on the above technical solution, the driving mode switching condition includes that the torque jointly driven by the driving motor and the engine is greater than the torque driven by the driving motor alone.

[0114] In some embodiments of the present application, based on the above technical solution, the mode switching module 930 can be further configured to: reduce the torque of the engine and obtain the speed of the engine; when the speed of the engine and the wheel-end speed of the hybrid vehicle meet preset conditions, the driving mode of the hybrid vehicle is switched from the extended-range mode driven by the drive motor alone to the hybrid mode driven by the drive motor and the engine together.

[0115] In some embodiments of the present application, based on the above technical solution, the vehicle controller further includes:

[0116] The required power determination module is configured to obtain the vehicle speed and wheel-end required torque of the hybrid vehicle; determine the required power of the drive motor based on the vehicle speed and wheel-end required torque, and the required power of the drive motor is positively correlated with the vehicle speed and wheel-end required torque.

[0117] In some embodiments of the present application, based on the above technical solution, the required power determination module can be further configured to: obtain the vehicle speed of the hybrid vehicle according to the vehicle speed sensor of the hybrid vehicle; obtain the wheel-end required torque of the hybrid vehicle according to the accelerator pedal depth of the hybrid vehicle.

[0118] Figure 10 shows a schematic diagram of the structure of a hybrid vehicle in one embodiment of the present application. As shown in Figure 10, the hybrid vehicle in this embodiment of the present application includes a vehicle controller 1000, which may include one or more of the following components: a processor 1001, a memory 1002, and one or more application programs. The 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 are configured to execute the hybrid vehicle driving method described in the aforementioned method embodiment.

[0119] Processor 1001 may include one or more processing cores. Processor 1001 utilizes various interfaces and circuits to connect various components of the hybrid vehicle. It executes instructions, programs, code sets, or instruction sets stored in memory 1002, as well as accesses data stored in memory 1002, to perform various hybrid vehicle functions and process data. Optionally, processor 1001 may be implemented using at least one of the following hardware forms: a digital signal processing (DSP), a field-programmable gate array (FPGA), or a programmable logic array (PLA). Processor 1001 may integrate one or a combination of a central processing unit (CPU), a graphics processing unit (GPU), and a modem. The CPU primarily processes the operating system, user interface, and application programs; the GPU is responsible for rendering and drawing display content; and the modem handles wireless communications. It is understood that the modem may not be integrated into processor 1001 but may be implemented separately via a communications chip.

[0120] Memory 1002 may include random access memory (RAM) or read-only memory (ROM). Memory 1002 may be used to store instructions, programs, code, code sets, or instruction sets. Memory 1002 may include a program storage area and a data storage area. The program storage area may store instructions for implementing an operating system, instructions for implementing at least one function, and instructions for implementing the various method embodiments described above. The data storage area may also store data generated by the hybrid vehicle during use.

[0121] In particular, according to an embodiment of the present application, the processes described in the various method flow charts can be implemented as computer software programs. For example, an embodiment of the present application includes a computer program product comprising a computer program carried on a computer-readable medium, the computer program containing program code for executing the methods shown in the flow charts. In such an embodiment, the computer program can be downloaded and installed from a network via a communication portion, and / or installed from a removable medium. When the computer program is executed by a processor, the various functions defined in the system of the present application are performed.

[0122] 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 may be, for example, but not limited to, an electrical, magnetic, optical, electromagnetic, infrared, or semiconductor system, device or component, or any combination of the above. More specific examples of computer-readable storage media may include, but are not limited to: an electrical connection with one or more wires, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM), a flash memory, an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the above. In the present application, a computer-readable storage medium may be any tangible medium containing or storing a program that can be used by or in combination with an instruction execution system, device or device. In the present application, a computer-readable signal medium may include a data signal propagated in baseband or as part of a carrier wave, which carries a computer-readable program code. Such propagated data signals may take various forms, including but not limited to electromagnetic signals, optical signals, or any suitable combination thereof. A computer-readable signal medium may also be any computer-readable medium other than a computer-readable storage medium that can transmit, 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 suitable medium, including but not limited to wireless, wired, or any suitable combination thereof.

[0123] The flowcharts and block diagrams in the accompanying drawings illustrate the possible implementation architecture, functions and operations of the systems, methods and computer program products according to various embodiments of the present application. In this regard, each box in the flowchart or block diagram can represent a module, program segment, or a part of code, and the above-mentioned module, program segment, or a part of code contains one or more executable instructions for realizing the specified logical function. It should also be noted that in some alternative implementations, the functions marked in the box can also occur in an order different from that marked in the accompanying drawings. For example, two boxes represented in succession can actually be executed substantially in parallel, and they can sometimes be executed in the opposite order, depending on the functions involved. It should also be noted that each box in the block diagram or flowchart, and the combination of the boxes in the block diagram or flowchart, can be implemented with a dedicated hardware-based system that performs the specified function or operation, or can be implemented with a combination of dedicated hardware and computer instructions.

[0124] It should be noted that, although several modules or units of the device for action execution are mentioned in the above detailed description, this division is not mandatory. In fact, according to the embodiment of the application, the features and functions of two or more modules or units described above can be concretized in one module or unit. On the contrary, the features and functions of one module or unit described above can be further divided into multiple modules or units to be concretized.

[0125] Through the description of the above embodiments, it is easy for those skilled in the art to understand that the example embodiments described herein can be implemented by software or by combining software with necessary hardware. Therefore, the technical solution according to the embodiments of the present application can be embodied in the form of a software product, which can be stored in a non-volatile storage medium (which can be a CD-ROM, a USB flash drive, a mobile hard disk, etc.) or on a network, and includes several instructions to enable a computing device (which can be a personal computer, a server, a touch terminal, or a network device, etc.) to execute the method according to the embodiments of the present application.

[0126] Those skilled in the art will readily appreciate other embodiments of the present invention after considering the specification and practicing the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of the present invention that follow the general principles of this application and include common knowledge or customary techniques in the art that are not disclosed herein.

[0127] It should be understood that the present application is not limited to the exact structures described above and shown in the drawings, and that various modifications and changes may be made without departing from the scope thereof. The scope of the present application is limited only by the appended claims.

Claims

1. A driving method for a hybrid vehicle, characterized in that, Including: When the hybrid vehicle accelerates, determine the target speed of the engine according to the state of charge of the power battery, and the target speed is lower than the maximum speed of the engine; When the speed of the engine reaches the target speed, maintain the speed of the engine unchanged, and adjust the torque of the engine according to the required power of the drive motor; When the drive mode switching condition is met, switch the drive mode of the hybrid vehicle from the range-extending mode driven by the drive motor alone to the series-parallel mode driven by the drive motor and the engine together.

2. The driving method of the hybrid vehicle according to claim 1, characterized in that, Determining the target speed of the engine according to the state of charge of the power battery includes: Determine the output power of the power battery according to the state of charge of the power battery; Determine the required power of the engine according to the output power of the power battery, and the required power of the engine is negatively correlated with the output power of the power battery; Determine the target speed of the engine according to the required power of the engine.

3. The driving method of the hybrid vehicle according to claim 2, wherein Determining the target speed of the engine according to the required power of the engine includes: Obtain the external characteristic curve of the engine; Query the external characteristic curve according to the required power of the engine to obtain the target speed of the engine.

4. The driving method of a hybrid vehicle according to claim 2, characterized in that, Determining the required power of the engine according to the output power of the power battery includes: Obtain the peak power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator; Determine the required power of the engine according to the peak power of the drive motor, the system efficiency of the drive motor, the system efficiency of the generator, and the output power of the power battery. The required power of the engine is positively correlated with the peak power of the drive motor, and the required power of the engine is negatively correlated with the system efficiency of the drive motor and the system efficiency of the generator.

5. The driving method of the hybrid vehicle according to claim 1, characterized in that, Adjusting the torque of the engine according to the required power of the drive motor includes: Obtain the system efficiency of the drive motor and the system efficiency of the generator; Determine the required power of the engine according to the required power of the drive motor, the system efficiency of the drive motor, and the system efficiency of the generator; Adjust the torque of the engine according to the required power of the engine.

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

7. The driving method of the hybrid vehicle according to claim 6, characterized in that, Switching the drive mode of the hybrid vehicle from the range-extending mode driven by the drive motor alone to the series-parallel mode driven by the drive motor and the engine together includes: Reduce the torque of the engine and obtain the speed of the engine; When the speed of the engine and the wheel-end speed of the hybrid vehicle meet the preset conditions, switch the drive mode of the hybrid vehicle from the range-extending mode driven by the drive motor alone to the series-parallel mode driven by the drive motor and the engine together.

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 drive motor, the method further includes: Obtain the vehicle speed and the wheel-end required torque of the hybrid vehicle; Determine the required power of the drive motor according to the vehicle speed and the required torque at the wheel end, and the required power of the drive motor has a positive correlation with the vehicle speed and the required torque at the wheel end.

9. The driving method of a hybrid vehicle according to claim 8, characterized in that, Obtain the vehicle speed and the required torque at the wheel end of the hybrid vehicle, including: Obtain the vehicle speed of the hybrid vehicle according to the vehicle speed sensor of the hybrid vehicle; Obtain the required torque at the wheel end of the hybrid vehicle according to the depth of the accelerator pedal of the hybrid vehicle.

10. A hybrid vehicle, characterized in that, Include: A vehicle controller for implementing the drive method of the hybrid vehicle according to any one of claims 1 to 9.

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