Vehicle control method and vehicle

Abstract

The invention relates to the technical field of hybrid vehicles, and provides a vehicle control method and a vehicle. The method comprises the following steps: acquiring a motor running state in a power shunting mode; if the running state of the motor is an overspeed state, a clutch is controlled to be opened; after the clutch is opened, the engine rotating speed is controlled to be reduced to a preset first range along with the output shaft rotating speed; determining a first target rotating speed of the motor based on the engine rotating speed, wherein the first target rotating speed does not exceed a preset maximum motor rotating speed limit; and controlling the rotating speed of a motor of the hybrid vehicle based on the first target rotating speed. When the motor of the hybrid vehicle is overspeed, the clutch can be controlled to be opened, the rotating speed of the engine is reduced, the rotating speed of the motor is controlled, the motor is protected, and the running safety of the vehicle is guaranteed.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of hybrid vehicles, in particular to a vehicle control method and vehicle. BACKGROUND

[0002] A hybrid vehicle, also known as a Hybrid Electric Vehicle (HEV), is a vehicle that combines an engine and an electric motor as power sources. When only the electric motor is used for driving, it is in pure electric mode, and when the electric motor and engine are used together for driving, it is in hybrid mode. By changing the driving mode, the hybrid vehicle can adapt to different operating scenarios to meet the torque and speed requirements of the vehicle. Hybrid vehicles are increasingly popular in the market due to their long driving range, low fuel consumption, low emissions, and no charging problems.

[0003] Power split is a specific technology in hybrid mode, which distributes the power generated by the engine to the electric motor and drive wheels through a specific mechanical structure such as a planetary gear set. In a power split system, the power of the engine can be divided into mechanical power and electrical power at the input end, which are used for generating electricity and directly driving the wheels, respectively. In this mode, the electric motor and engine can work more flexibly to adapt to different driving conditions.

[0004] Currently, a common input power split configuration consists of an engine, a generator, a drive motor, a planetary gear set, and a gear shifting mechanism. The engine and generator are connected to different shafts of the planetary gear set, and the drive motor is directly connected to the output shaft. The engine's power is divided into two parts through the planetary gear set, one part directly drives the wheels, and the other part is used for generating electricity. The electrical energy is transmitted to the drive motor, which is ultimately combined on the output shaft. A typical example is the Toyota THS hybrid system.

[0005] A second power split configuration also exists in related technologies, which consists of an engine, a front axle motor, a planetary gear set, and a gear shifting mechanism. The engine and front axle motor are connected to different shafts of the planetary gear set, and the engine's power is divided into two parts through the planetary gear set, one part directly drives the wheels, and the other part is used for generating electricity. The electrical energy is transmitted to the power battery or rear axle motor. A typical example is the patent document with application number 202321764877.9, which discloses a configuration of this type. In power split mode, the front axle motor acts as a generator, and in pure electric mode, the front axle motor acts as a drive motor.

[0006] The inventor of the present application finds that the hardware structure relationship of the second power split configuration determines that the output shaft speed, the engine speed and the front axle motor speed of the vehicle in the power split mode are related to each other. For example, under the condition that the engine speed is fixed, the output shaft speed increases, which causes the front axle motor speed to decrease (i.e., to increase in the opposite direction). Based on this, in some road conditions, such as the road condition scenario in which the left front wheel is in the snow and the right front wheel is on the normal road, the left front wheel speed increases, which causes the output shaft speed to increase, and further causes the front axle motor speed to increase in the opposite direction, which may exceed the design threshold of the reverse rotation speed of the front axle motor, thereby easily causing damage to the motor hardware or affecting the service life of the motor. SUMMARY

[0007] The present application provides a vehicle control method and device and a vehicle to solve the problem of motor reverse overspeed of a hybrid vehicle in some scenarios, which easily causes damage to the motor hardware or affects the service life of the motor.

[0008] In a first aspect, the present application provides a vehicle control method, comprising:

[0009] acquiring a motor operating state in a power split mode;

[0010] if the motor operating state is an overspeed state, controlling a clutch to open;

[0011] controlling the engine speed to decrease to a preset first range following the output shaft speed after the clutch is opened;

[0012] determining a first target motor speed based on the engine speed, wherein the first target motor speed does not exceed a preset maximum motor speed limit;

[0013] controlling the motor speed of the hybrid vehicle based on the first target motor speed.

[0014] As can be seen from the above, the present application acquires the motor operating state in the power split mode, controls the clutch to open when the motor operating state is an overspeed state, and controls the engine speed to decrease to a preset first range following the output shaft speed after the clutch is opened. Since the driving force cannot be transmitted to the output shaft after the clutch is opened, the output shaft speed decreases, and the engine speed also decreases following the output shaft speed. Since the engine speed and the motor speed are related to each other due to the configuration, the first target motor speed determined based on the engine speed decreases after the engine speed decreases. If the first target motor speed is lower than the maximum motor speed limit of the motor, the motor speed of the hybrid vehicle is controlled based on the first target motor speed, thereby solving the problem of motor overspeed, protecting the motor, and ensuring the safety of vehicle operation.

[0015] Based on the first aspect, in a possible implementation manner, the control of the clutch to open comprises:

[0016] limiting the engine torque and the motor torque to zero;

[0017] controlling the clutch to open after the engine torque and the motor torque are zero and for a preset first duration.

[0018] The application can reduce impact to ensure smooth transition of the power system by limiting the engine torque and the motor torque first and then opening the clutch.

[0019] In a possible implementation manner of the first aspect, the controlling the engine speed to follow the output shaft speed to decrease to the preset first range comprises:

[0020] obtaining an engine first target speed curve based on the output shaft speed;

[0021] controlling the engine speed to decrease to the preset first range by a first PI torque speed control loop based on the first target speed curve.

[0022] The application can realize accurate control of the engine speed by the PI torque speed control loop, and can improve the response speed of the control to ensure stability of the power system.

[0023] In a possible implementation manner of the first aspect, the determining the motor first target speed based on the engine speed comprises:

[0024] obtaining a motor speed target value based on the engine speed, the output shaft speed and the gear speed ratio;

[0025] determining the motor speed target value that is not greater than a preset maximum motor speed limit value as the first target speed.

[0026] The application can realize speed reduction control of the motor by limiting the motor target speed below the maximum motor speed limit value, so that the motor can be out of the overspeed state.

[0027] In a possible implementation manner of the first aspect, the method further comprises:

[0028] if the target operating mode and the actual operating mode of the hybrid vehicle are both the power split mode, determining that the hybrid vehicle operates in the power split mode;

[0029] Correspondingly, after obtaining the motor operating state in the power split mode, the method further comprises:

[0030] if the motor operating state is the overspeed state, prohibiting switching the target operating mode to the series mode or the direct drive mode.

[0031] The application prohibits specific operation mode switching when the motor is in an overspeed state, can avoid system control conflicts, and maintains stable operation of the control system.

[0032] In a possible implementation manner of the first aspect, before the motor operating state is acquired in the power split mode, the method further includes:

[0033] If the current driving mode is the preset driving mode, and the absolute value of the actual motor speed is higher than the preset first speed threshold, and the front axle left and right wheel speed difference is greater than the preset calibration threshold, it is determined that the motor operating state is an overspeed state.

[0034] If the current driving mode is not the preset driving mode, or the absolute value of the actual motor speed is not higher than the preset first speed threshold, or the front axle left and right wheel speed difference is not higher than the preset calibration threshold, it is determined that the motor operating state is a non-overspeed state.

[0035] The implementation manner can more accurately determine the overspeed state of the motor by the conditions of the driving mode, the actual motor speed, and the front axle left and right wheel speed difference.

[0036] In a possible implementation manner of the first aspect, after the motor speed control is performed on the motor of the hybrid vehicle based on the first target speed, the method further includes:

[0037] The second target speed of the motor is obtained based on the engine speed, the output shaft speed, and the target gear ratio.

[0038] If the second target speed is lower than a preset second speed threshold, and the duration for being lower than the preset second speed threshold is not less than a preset second duration, and the front axle left and right wheel speed difference is not higher than the preset calibration threshold, it is determined that the motor operating state changes from the overspeed state to the non-overspeed state.

[0039] The second speed threshold is less than the maximum motor speed limit.

[0040] The implementation manner can more accurately determine the change of the motor from the overspeed state to the non-overspeed state by the conditions of the second target speed of the motor, the duration for satisfying a specific condition, and the front axle left and right wheel speed difference.

[0041] In a possible implementation manner of the first aspect, the method further includes:

[0042] If the motor operating state changes from the overspeed state to the non-overspeed state, the clutch is controlled to be closed.

[0043] The clutch torque capacity is increased based on a preset gradient after the clutch is closed.

[0044] After the clutch torque capacity increases to a preset threshold, the requested engine torque is based on the front axle torque distribution, and the requested motor torque is based on the front axle torque distribution.

[0045] The present implementation closes the clutch and performs the front axle torque distribution strategy after the motor transitions to the non-over-speed state, thereby restoring the normal driving operation state of the vehicle, and the gradient increase of the clutch torque capacity can help achieve smoother power transmission.

[0046] This is because as the torque gradually increases, the impact of the powertrain will be reduced, thereby improving the driving experience. The engagement degree of the clutch can be more accurately controlled, which is very beneficial for applications that require precise control of power flow

[0047] Based on the first aspect, in a possible implementation, the control of the clutch closure includes:

[0048] Based on the output shaft speed, a second target engine speed curve is obtained;

[0049] Based on the second target speed curve, the second PI torque speed control loop is used to control the engine speed to follow the output shaft speed and stabilize in a preset second range;

[0050] After the speed difference on both sides of the clutch is lower than a preset first speed difference threshold, the motor speed control is released, the clutch is pre-charged for a preset third time, and after the pre-charging is completed, the clutch torque is gradually increased to a preset first torque range;

[0051] After the motor speed control is released, the engine speed control is released;

[0052] After the speed difference on both sides of the clutch is lower than a preset second speed difference threshold, the clutch is controlled to close for a preset fourth time, wherein the second speed difference threshold is less than the first speed difference threshold.

[0053] The present implementation can achieve precise control and improve control response speed of the engine speed through the PI torque speed control loop, thereby ensuring the stability of the powertrain. On the other hand, by monitoring the speed difference on both sides of the clutch, a smaller speed difference means that the impact during power transmission will be smaller, thereby performing the clutch closing operation at the appropriate time, which is beneficial for achieving smooth power conversion.

[0054] Secondly, the present application provides a control device of a vehicle, which comprises:

[0055] A state acquisition unit is configured to acquire a motor operating state in a power split mode;

[0056] A clutch control unit is configured to control the clutch to open if the motor operating state is an over-speed state;

[0057] an engine speed control unit, configured to control the engine speed to follow the output shaft speed to decrease to a preset first range after the clutch is opened;

[0058] a motor speed determination unit, configured to determine a first target motor speed based on the engine speed, wherein the first target motor speed is not greater than a preset maximum motor speed limit;

[0059] a motor speed control unit, configured to control the motor speed of the hybrid vehicle based on the first target motor speed.

[0060] With reference to the second aspect, in a possible implementation manner, the clutch control unit is specifically configured to limit the engine torque and the motor torque to zero, and control the clutch to be opened after the engine torque and the motor torque are zero and a preset first time duration is continued.

[0061] With reference to the second aspect, in a possible implementation manner, the engine speed control unit is specifically configured to obtain an engine first target speed curve based on the output shaft speed, and control the engine speed to decrease to the preset first range by a first PI torque speed control loop based on the first target speed curve.

[0062] With reference to the second aspect, in a possible implementation manner, the motor speed determination unit is specifically configured to obtain a motor speed target value based on the engine speed, the output shaft speed and the gear ratio, and determine the first target motor speed as the motor speed target value that is not greater than the preset maximum motor speed limit.

[0063] With reference to the second aspect, in a possible implementation manner, the apparatus further includes:

[0064] a split mode determination unit, configured to determine that the hybrid vehicle operates in the power split mode if the target operation mode and the actual operation mode of the hybrid vehicle are both the power split mode;

[0065] a switching control unit, configured to prohibit the target operation mode from being switched to the series mode or the direct drive mode if the motor operating state is the overspeed state.

[0066] With reference to the second aspect, in a possible implementation manner, the apparatus further includes:

[0067] an operating state determination unit, configured to determine that the motor operating state is the overspeed state if the current driving mode is a preset driving mode, the absolute value of the actual motor speed is higher than a preset first speed threshold, and the speed difference between the left wheel and the right wheel of the front axle is greater than a preset calibration threshold before the state acquisition unit acquires the motor operating state in the power split mode.

[0068] If the current driving mode is not the preset driving mode, or the absolute value of the actual motor speed is not higher than the preset first speed threshold, or the speed difference between the left and right front axle wheels is not higher than the preset calibration threshold, then the motor operating state is determined to be non-overspeed state.

[0069] Based on the second aspect, in one possible implementation, the device further includes:

[0070] The state switching determination unit is used to determine the second target speed of the motor based on the engine speed, output shaft speed and target gear ratio after the motor speed control unit controls the motor speed of the hybrid vehicle based on the first target speed. If the second target speed is lower than a preset second speed threshold, and the duration of the lower speed threshold is not less than a preset second duration, and the speed difference between the left and right front axles is not higher than a preset calibration threshold, then the motor operating state is determined to change from an overspeed state to a non-overspeed state. Wherein, the second speed threshold is less than the maximum motor speed limit.

[0071] Based on the second aspect, in one possible implementation, the clutch control unit is further configured to: control the clutch to close if the motor operating state changes from an overspeed state to a non-overspeed state; increase the clutch torque capacity based on a preset gradient after the clutch is closed; request engine torque distribution based on front axle torque after the clutch torque capacity increases to a preset threshold; and request motor torque distribution based on front axle torque.

[0072] Based on the second aspect, in one possible implementation, the clutch control unit is further used for,

[0073] The second target engine speed curve is obtained based on the output shaft speed;

[0074] Based on the second target speed curve, the second PI torque speed control loop is used to control the engine speed to follow the output shaft speed and stabilize it within the preset second range.

[0075] After the speed difference between the two ends of the clutch is lower than the preset first speed difference threshold, the motor speed control is released, and the clutch is pre-charged within a preset third time period. After the pre-charging is completed, the clutch torque is gradually increased to the preset first torque range.

[0076] After disengaging the motor speed control, disengage the engine speed control;

[0077] After the speed difference between the two ends of the clutch is lower than the preset second speed difference threshold, the clutch is controlled to close within a preset fourth time period, wherein the second speed difference threshold is less than the first speed difference threshold.

[0078] Thirdly, this application provides a vehicle comprising:

[0079] a memory for storing executable program code;

[0080] a processor for calling and running the executable program code from the memory, so that the vehicle executes the control method described above.

[0081] In a fourth aspect, the present application provides a computer readable storage medium, which stores a computer program, and the computer program is executed by a processor to implement the control method described above.

[0082] In a fifth aspect, the present application provides a computer program product containing instructions, which, when executed on a computer, cause the computer to perform the steps of the control method described above.

[0083] It can be understood that the beneficial effects of the second aspect, the third aspect, the fourth aspect and the fifth aspect described above can be referred to the related description in the first aspect, which will not be repeated here. BRIEF DESCRIPTION OF DRAWINGS

[0084] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments or the prior art description. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0085] Figure 1 is a structural schematic diagram of a first power split configuration of a vehicle provided by the embodiments of the present application;

[0086] Figure 2 is a structural schematic diagram of a second power split configuration of a vehicle provided by the embodiments of the present application;

[0087] Figure 3 is a structural schematic diagram of a front axle of the vehicle of the second power split configuration provided by the embodiments of the present application;

[0088] Figure 4 is an implementation flowchart of a control method of a vehicle provided by the embodiments of the present application;

[0089] Figure 5 is a structural schematic diagram of a control device of a vehicle provided by the embodiments of the present application;

[0090] Figure 6 is a structural schematic diagram of a vehicle provided by the embodiments of the present application. DETAILED DESCRIPTION

[0091] In the following description, specific details such as particular system architectures and techniques are set forth for illustrative purposes and not for limitation, in order to provide a thorough understanding of the embodiments of this application. However, those skilled in the art will understand that this application may also be implemented in other embodiments without these specific details. In other instances, detailed descriptions of well-known systems, apparatuses, circuits, and methods have been omitted so as not to obscure the description of this application with unnecessary detail.

[0092] To make the objectives, technical solutions, and advantages of this application clearer, the embodiments of this application will be described in further detail below with reference to the accompanying drawings.

[0093] It should be understood that "multiple" as mentioned in this application refers to two or more. In the description of this application, unless otherwise stated, " / " indicates "or," for example, A / B can mean A or B; "and / or" in this document is merely a description of the relationship between related objects, indicating that three relationships can exist, for example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Furthermore, to facilitate a clear description of the technical solutions of this application, the terms "first," "second," etc., are used to distinguish identical or similar items with essentially the same function and effect. Those skilled in the art will understand that the terms "first," "second," etc., do not limit the quantity or execution order, and that "first," "second," etc., do not necessarily imply differences.

[0094] The configuration of the hybrid vehicle involved in the embodiments of this application will be explained below.

[0095] First, this application introduces the first power split configuration of hybrid vehicles mentioned in the background section, such as... Figure 1 As shown, this power split configuration typically consists of an engine, a generator, an electric motor, a power distribution unit, and an output chain. For example, the power distribution unit here is a single-row planetary gear set, the output chain may include a transmission mechanism, and both the generator and the electric motor are front axle motors. The engine and generator are connected to different shafts of the planetary gear set (e.g., ...). Figure 1 As shown, the engine is connected to the planet carrier of the planetary mechanism, the generator is connected to the sun gear of the planetary mechanism, and the electric motor is directly connected to the output chain. The power of the engine is divided into two parts through the planetary mechanism. One part is directly output to the output chain to drive the wheel (mechanical energy, through the planet carrier and the external gear ring to the output chain), and the other part is used to generate electricity. The electrical energy is then transmitted to the electric motor and finally merges back to the output chain to drive the wheel (electrical energy, through the planet carrier, the sun gear, the generator, and the electric motor to the output chain).

[0096] Next, we introduce the second power split configuration of hybrid vehicles mentioned in the background technology of this application, such as... Figure 2As shown, the configuration consists of an engine, a front axle motor, a power distribution device and an output chain. Similarly, the power distribution device here is a single-row planetary mechanism (planetary gear set), and the output chain can include a variable speed mechanism. The engine and the front axle motor are connected to different shafts of the planetary mechanism (e.g. Figure 2 As shown, the engine is connected to the planet carrier of the planetary mechanism, and the generator is connected to the sun gear of the planetary mechanism), the power of the engine is split by the planetary mechanism, one part is directly output to the output chain to drive the wheels (mechanical energy, through the planet carrier, the outer ring gear to the output chain), and the other part is used for power generation, and the electric energy is transmitted to the power battery or the rear axle motor (electric energy, through the planet carrier, the sun gear, the front axle motor, the rear axle motor or the power battery), and this part of the electric energy is used for rear axle drive.

[0097] Based on the above, comparing the two power split configurations, the second power split configuration only includes one front axle motor, which functions as a generator in the power split mode, converting part of the output power of the engine into electric energy and transmitting it to the rear axle motor and / or the power battery. The second power split configuration reduces one drive motor in the front axle compared to the first power split configuration, and the driving power of the front axle is only a part of the engine power.

[0098] In the second power split configuration, when the driving mode of the vehicle is in the power split mode, the relationship between the output shaft speed (or vehicle speed), the engine speed and the front axle motor speed is similar to a lever principle, with the engine speed as the fulcrum and the output shaft speed (or vehicle speed) and the front axle motor speed on the left and right sides, respectively, which will affect each other. For example, under the condition that the engine speed is fixed, an increase in the output shaft speed will cause the front axle motor speed to decrease (or increase in the opposite direction).

[0099] In combination with Figure 1 And Figure 2 It should also be noted that in the first power split configuration, the output shaft speed is related not only to the engine speed and the generator speed, but also to the electric motor (i.e., the drive motor), so when the output shaft speed is increased under the above specific working conditions, it can be adjusted and controlled by the electric motor, which usually does not affect the generator speed, preventing it from reversing and overspeeding. In the second power split configuration, since the drive motor is reduced, the output shaft speed cannot be adjusted by other power transmission links when the engine speed is constant, only the front axle motor speed is affected, which may cause it to reverse and overspeed.

[0100] To further illustrate the relationship between the output shaft speed (or vehicle speed), the engine speed and the front axle motor speed, Figure 3 A specific structural diagram of the front axle of the hybrid vehicle in the second power split configuration is given as follows: Figure 3As shown, the cut-off device C1 is located between the output end of the engine A1 and the planetary mechanism 20, and the planetary mechanism 30 is a single-row planetary gear set known to those skilled in the art, which includes a sun gear 21, a planet carrier 23 and a ring gear 22, the sun gear 21 is in meshing connection with a plurality of planet gears in the planetary mechanism 20, and the ring gear 22 is also in meshing connection with the plurality of planet gears, the plurality of planet gears are rotationally supported on the planet carrier 23, and the transmission relationship of the single-row planetary gear set is known to those skilled in the art, which will not be described here.

[0101] Further, as shown, Figure 3 The hybrid power transmission system further includes a transmission mechanism 30, and in an embodiment, the first engagement element S1 is arranged between the planet carrier and the transmission mechanism. The first engagement element S1 can be a synchronizer or a dog clutch known to those skilled in the art, which is a bidirectional engagement synchronizer or dog clutch, that is, the first engagement element S1 can be selectively engaged or disengaged with the components arranged on both sides thereof. When the first engagement element S1 is engaged with the planet carrier 23, the ring gear 22 is in power connection with the planet carrier 23, so that the planetary mechanism 20 forms an integral whole, and the power transmitted by the engine A1 or the front axle motor 10 to the planetary mechanism 20 is outputted at a 1:1 ratio; when the first engagement element S1 is not engaged, the power transmitted by the engine A1 and the front axle motor 10 to the planetary mechanism 20 is distributed by the gears meshing inside the planetary mechanism 20, and a continuous speed ratio is outputted; when the first engagement element S1 is engaged with the transmission mechanism 30, the power transmitted by the engine A1 and the motor to the planetary mechanism is distributed by the gears meshing inside the planetary mechanism 20, and then transmitted to a gear in the transmission mechanism 30, so as to realize the output of the gear.

[0102] When the vehicle is in the power split driving mode, the first engagement element S1 is not engaged, the front axle motor 10 acts on the sun gear 21, and the engine A1 transmits power to the planet carrier 23 through the cut-off device C1, so as to transmit the power to the sun gear 21 and the ring gear 22 through the meshing of the gears inside the planetary mechanism 20: part of the power is transmitted to the front axle motor 10 by the sun gear 21, and the front axle motor 10 generates electricity under the control of the motor controller; the other part of the power is transmitted to the intermediate shaft by the ring gear 22, and then different gears are selected by the transmission mechanism 30 to realize different gear outputs.

[0103] As can be known from the above structural description, when the vehicle is in the power split driving mode, part of the torque output by the engine is provided to the front axle through the planetary mechanism and the transmission mechanism, for providing driving force to the front axle, and the other part of the torque is transmitted to the front axle motor through the planetary mechanism, for controlling the front axle motor to generate electricity to meet the power demand of the vehicle.

[0104] For example, in a specific architecture, the vehicle speed, the engine speed and the front axle motor speed of the hybrid vehicle have the following relationship:

[0105] nc = V x ig / 0.337 / Rw x K (1 + K) + ns * 1 / (1 + K)

[0106] Wherein, nc represents the engine speed corresponding to the target gear; V represents the current vehicle speed (which can also be converted into the output shaft speed); ig represents the speed ratio of the target gear; Rw represents the tire radius of the vehicle; K represents the speed ratio of the planetary mechanism of the vehicle; ns represents the front axle motor speed.

[0107] It can be seen that, under the condition that the engine speed is fixed, the output shaft speed increases, which will cause the front axle motor speed to decrease (i.e. increase in reverse).

[0108] Based on this, in some road conditions, such as the road condition scene where the left front wheel is on snow and the right front wheel is on normal road, the left front wheel speed will increase, causing the output shaft speed to increase, which may cause the front axle motor speed to increase in reverse, which may exceed the reverse speed design threshold of the front axle motor, thereby easily causing the hardware damage of the front axle motor or affecting the service life of the front axle motor.

[0109] In view of the above problems, the embodiments of the present application provide a vehicle control method, which can control the motor to slow down when the reverse overspeed of the motor is detected, so as to avoid the hardware damage of the motor or affect the service life of the motor, and ensure the driving safety.

[0110] The vehicle control method provided by the embodiments of the present application will be explained and described in detail below.

[0111] It should be noted that the control method provided by the embodiments can be applied to a hybrid vehicle, and the execution subject of the vehicle method can be one or more controllers of the hybrid vehicle, such as a vehicle control unit (VCU), a transmission control unit (TCU), a control device integrating TCU and VCU, or an engine control module (ECM), etc.

[0112] It should also be noted that the motor that occurs reverse overspeed in the embodiments refers to the motor that participates in power split and converts part of the mechanical energy of the engine into electrical energy, and is not limited to the front axle motor. For example, in actual application, the front axle configuration in the embodiments can also be interchanged with the rear axle.

[0113] Referring to Figure 4 which shows the implementation flowchart of the vehicle control method provided by the embodiments of the present application, which is described in detail as follows:

[0114] In step 401, the motor operating state is acquired in the power split mode.

[0115] In the embodiment of the present application, the power split mode refers to a mode in which the hybrid vehicle is driven by the engine and the motor in cooperation, a part of the output power of the engine is split by the power distribution device to the transmission mechanism and the output shaft to drive the wheels, and another part is split by the power distribution device to the front axle motor and converted into electric energy by the front axle motor and output to the rear axle motor or the power battery.

[0116] In some implementations, it can be determined whether the current is the power split mode based on the operating mode of the vehicle. For example, when the target operating mode of the vehicle is the power split mode and the actual operating mode is the power split mode, it can be determined that the vehicle is currently in the power split mode.

[0117] The motor operating state can include an overspeed state and a non-overspeed state. The overspeed state refers to a state in which the motor speed exceeds the designed maximum speed limit. Correspondingly, the non-overspeed state refers to a state in which the motor speed does not exceed the designed maximum speed limit. In the embodiment of the present application, the motor overspeed refers to the reverse overspeed of the front axle motor, that is, a part of the mechanical energy of the engine is converted into electric energy in the power split mode. In this working condition, the front axle motor operates as a generator and is in a reverse state (the front axle motor drives the vehicle, which is defined as forward rotation). Therefore, the motor overspeed in this embodiment refers to the reverse overspeed, that is, the reverse speed exceeds the designed maximum reverse speed limit.

[0118] In some implementations, in order to better protect the motor, a buffer interval can be set before the speed limit is reached. When the motor speed enters the buffer interval, it is determined to be in an overspeed state. For example, the motor speed limit is 7000 rpm, and the buffer interval can be defined as 6800-7000 rpm. Therefore, when the motor speed exceeds 6800 rpm, it is also determined to be in an overspeed state.

[0119] In addition, it should be noted that the problem of motor reverse overspeed in the present application can occur in some specific off-road road conditions, that is, road surfaces with high load demand, such as snow, mud, sand, etc. When driving on these road surfaces, the difference in road friction of the two front wheels may be too large, resulting in reverse overspeed of the motor. Therefore, in the embodiment of the present application, the driving mode can also be calibrated. When the driving mode of the vehicle is the calibrated mode, the problem of reverse overspeed of the motor can occur. The calibrated driving mode can include: snow mode, mud mode, sand mode, high-speed four-wheel drive mode or low-speed four-wheel drive mode. Therefore, in some implementations, the current driving mode of the vehicle can also be used as one of the conditions for determining whether the motor operating state is in a reverse overspeed state.

[0120] In some embodiments, the actual gear of the vehicle can also be used as one of the conditions for determining whether the motor operating state is in the reverse overspeed state. For example, when the motor operating state is in the reverse overspeed state, the actual gear of the vehicle should be in one of the gears 1 / 2 / 3 / R (referring to the transmission mechanism shown in FIG. 3). Figure 3

[0121] In an optional embodiment, before step 301, the control method can further include:

[0122] If the current driving mode is the preset driving mode, the absolute value of the actual motor speed is higher than the preset first speed threshold, and the speed difference between the left and right front wheels is greater than the preset calibration threshold, it is determined that the motor operating state is in the overspeed state.

[0123] If the current driving mode is not the preset driving mode, or the absolute value of the actual motor speed is not higher than the preset first speed threshold, or the speed difference between the left and right front wheels is not greater than the preset calibration threshold, it is determined that the motor operating state is not in the overspeed state.

[0124] In the embodiments of the present application, the preset driving mode can include the snow mode, the mud mode, the sand mode, the high-speed four-wheel drive mode, or the low-speed four-wheel drive mode. The first speed threshold can be the maximum speed limit of the motor, or a pre-calibrated value close to the maximum speed limit. The calibration threshold can be a pre-calibrated value related to the steering angle and the slope; the calibration threshold can represent the allowable speed difference between the left and right front wheels caused by the steering angle and the slope. Greater than the calibration threshold means that the speed difference between the left and right front wheels is not only caused by the steering angle and the slope, but is more likely caused by the driving mode and the specific road conditions, and the motor needs to be controlled in speed. Therefore, by combining the actual motor speed and the speed difference between the left and right front wheels, it can be more accurately determined whether the motor is overspeed.

[0125] In some embodiments, when it is detected that the motor operating state is in the overspeed state, a set motor overspeed flag can be activated. When the vehicle controller detects that the motor overspeed flag is activated, it is determined that the motor operating state is in the overspeed state. When the vehicle controller detects that the motor overspeed flag is not activated, it is determined that the motor operating state is not in the overspeed state.

[0126] In step 402, if the motor operating state is in the overspeed state, the clutch is controlled to be opened.

[0127] ​In the embodiment of the present application, when it is detected that the motor operating state is the overspeed state, it means that the reverse overspeed of the front axle motor has occurred or is about to occur. Therefore, the motor speed needs to be controlled, and since there is a certain coupling relationship between the motor speed and the engine speed, the engine speed needs to be reduced to reduce the motor speed, and since there is a coupling relationship between the engine speed and the output shaft speed, the engine needs to be separated from the transmission system, so the clutch needs to be opened first.

[0128] In an optional embodiment, the control of the opening of the clutch in step 402 can be implemented based on the following manner:

[0129] limiting the engine torque and the motor torque to zero; and after the engine torque and the motor torque are zero and for a preset first duration, controlling the opening of the clutch.

[0130] In a hybrid vehicle, the engine and the motor are connected to the transmission system through a clutch. When it is necessary to separate the engine and the transmission system, the output torque of the engine and the motor needs to be reduced to zero first to ensure smooth transition of the power system, reduce the wear of mechanical parts, and improve the efficiency and reliability of the overall system.

[0131] For example, taking the VCU as the execution subject, the VCU can send a clutch open request to the TCU, and limit the engine torque and the motor torque to 0 Nm. In addition, in order to be able to smoothly control the engine speed later, the VCU can also predefine an engine target speed curve following the output shaft speed. After the engine torque and the motor torque are limited to 0 Nm and for a preset first duration, and after the TCU receives the clutch open request from the VCU, the TCU can control the opening of the clutch.

[0132] In step 403, after the clutch is opened, the engine speed is controlled to follow the output shaft speed to decrease to a preset first range.

[0133] In the embodiment of the present application, after the clutch is opened, the engine is separated from the transmission system, and then the engine can be controlled to follow the output shaft speed to decrease. For example, based on the engine target speed curve predefined in the above embodiment to follow the change of the output shaft speed, the engine speed can be controlled to decrease to a preset first range, which represents a speed range that can make the motor speed out of the overspeed state.

[0134] In an optional embodiment, the control of the engine speed to follow the output shaft speed to decrease to a preset first range in step 403 can include:

[0135] obtaining an engine first target speed curve based on the output shaft speed;

[0136] Based on the first target engine speed curve, the engine speed is controlled to decrease to a preset first range by a first PI torque speed control loop.

[0137] For example, in the embodiment, the VCU can send a shift permission to the TCU after the clutch is opened, so as to match the actual gear with the engine speed. Meanwhile, a first PI torque speed control loop is activated to the ECM by using a predefined engine first target speed curve based on the output shaft speed, so as to control the engine speed to follow the output shaft speed to decrease to a preset first range. The engine speed can be controlled to decrease linearly by a proportional integral (PI) controller, so as to realize a stable and accurate decrease of the engine speed to the preset first range.

[0138] In step 404, a first target motor speed is determined based on the engine speed, wherein the first target motor speed is not greater than a preset maximum motor speed limit.

[0139] In the embodiment, the maximum motor speed limit refers to a designed maximum reverse rotation limit of the motor. If the reverse rotation speed of the motor exceeds the limit, the motor hardware can be damaged.

[0140] In an optional embodiment, the step 304 of determining the first target motor speed based on the engine speed can specifically include:

[0141] The motor speed target value is obtained based on the engine speed, the output shaft speed and the gear speed ratio;

[0142] The motor speed target value not greater than the preset maximum motor speed limit is determined as the first target motor speed.

[0143] In the embodiment, the target motor speed can be calculated based on the engine speed during the process of controlling the engine speed to decrease to the preset first range. Specifically, the matching relationship between the engine speed, the motor speed, the output shaft speed, the target gear speed ratio and the planetary mechanism speed ratio determined based on the hardware configuration can be used. Under the condition that the engine speed (real-time value), the output shaft speed (real-time value), the target gear speed ratio (constant value) and the planetary mechanism speed ratio (constant value) are known, the target motor speed is calculated.

[0144] If the calculated target motor speed is still greater than the preset maximum motor speed limit, the target motor speed is recalculated based on the real-time engine speed value. Since the engine speed is decreasing, the calculated target motor speed will be lower than the maximum motor speed limit as the real-time engine speed value decreases. At this time, the calculated target motor speed can be used as the first target motor speed.

[0145] For example, when the clutch is opened, the actual gear position is 1 / 2 / 3 / R, and the shift permission is received from the VCU, the TCU can request motor speed control and send the first target speed to the VCU, so that the VCU controls the motor speed based on the first target speed. During this process, the TCU can also set shift_in_progress to in progress and send it to the VCU to indicate that the transmission is in the process of shifting.

[0146] In step 405, the motor of the hybrid vehicle is controlled based on the first target speed.

[0147] In this embodiment, when the first target speed sent by the TCU requesting motor speed control is a speed value lower than the maximum motor speed limit, the result of controlling the motor speed based on the first target speed will make the motor speed out of the over-speed state, thereby solving the problem of the motor speed exceeding the maximum motor speed limit in this scenario and ensuring the safe operation of the motor.

[0148] As can be seen from the above, by obtaining the motor operating state in the power split mode, when the motor operating state is in the over-speed state, the clutch is first controlled to be opened, and the engine speed is controlled to follow the output shaft speed to decrease to a preset first range after the clutch is opened. Since the driving force cannot be transmitted to the output shaft after the clutch is opened, the output shaft speed will decrease, and the engine speed will also decrease following the output shaft speed. Since the engine speed and the motor speed are related due to the configuration, after the engine speed decreases, the first target speed of the motor determined based on the engine speed will also decrease. If it is lower than the maximum motor speed limit of the motor, the motor speed of the hybrid vehicle can be controlled based on the first target speed, thereby solving the problem of motor over-speed, achieving protection of the motor, and ensuring the safety of vehicle operation.

[0149] Based on the above embodiment, after step 405, the motor speed is controlled to decrease, and the motor will be out of the over-speed state and remain in the non-over-speed state. After the motor changes from the over-speed state to the non-over-speed state, the protection control of the motor speed needs to be released, and the normal operating state of the hybrid vehicle needs to be restored. The following embodiments are implemented based on this purpose.

[0150] First, it is necessary to identify that the motor has changed from the over-speed state to the non-over-speed state.

[0151] In an optional embodiment, after the motor of the hybrid vehicle is controlled based on the first target speed in step 405, the control method can further include:

[0152] The second target speed of the motor is obtained based on the engine speed, the output shaft speed, and the target gear ratio.

[0153] If the second target speed is lower than the preset second speed threshold, and the duration that the second target speed is lower than the preset second speed threshold is not less than the preset second duration, and the front axle left and right wheel speed difference is not higher than the preset calibration threshold, it is determined that the motor operating state is changed from the overspeed state to the non-overspeed state.

[0154] The second speed threshold is less than the maximum motor speed limit.

[0155] In the embodiments of the present application, whether the motor is changed from the overspeed state to the non-overspeed state can be detected based on three conditions. One is that the second target speed of the motor is lower than the preset second speed threshold, which is calculated based on the engine speed (real-time value), the output shaft speed (real-time value), the speed ratio (constant value) of the target gear, and the speed ratio (constant value) of the planetary mechanism. Here, the second speed threshold is less than the maximum motor speed limit. For example, the maximum motor speed limit is 7000 revolutions per minute, and the second speed threshold can be 6000 revolutions per minute. The second is that the duration that the second target speed is lower than the preset second speed threshold is not less than the preset second duration. For example, the preset second duration can be 50 milliseconds. The third is that the front axle left and right wheel speed difference is not higher than the calibration threshold, which represents the allowable front axle left and right wheel speed difference caused by the steering angle and the slope. When the three conditions are met, it is determined that the operating state is changed from the overspeed state to the non-overspeed state.

[0156] In some implementations, when it is detected that the motor operating state is in the overspeed state, a set motor overspeed flag is activated. When it is determined that the motor operating state is changed from the overspeed state to the non-overspeed state, the motor overspeed flag can be switched from the activated state to the inactivated state.

[0157] Secondly, when it is identified that the motor is changed from the overspeed state to the non-overspeed state, the aforementioned protection control of the motor speed needs to be released, and the normal operating state of the hybrid vehicle is restored.

[0158] Specifically, in an optional embodiment, the above control method can further include:

[0159] If the motor operating state is changed from the overspeed state to the non-overspeed state, the clutch is controlled to be closed.

[0160] After the clutch is closed, the clutch torque capacity is increased based on a preset gradient.

[0161] After the clutch torque capacity is increased to a preset threshold, the engine torque is requested to be based on the front axle torque distribution, and the motor torque is requested to be based on the front axle torque distribution.

[0162] In the embodiment, when it is identified that the motor is changed from the overspeed state to the non-overspeed state, the clutch is controlled to be closed to release the aforementioned protection control on the motor speed. After the clutch is closed, to maintain smooth switching of power, the clutch torque capacity can be increased based on a preset gradient, and after the clutch torque capacity is increased to a preset threshold, the engine torque is requested to be based on the front axle torque distribution, and the motor torque is requested to be based on the front axle torque distribution, so as to restore the normal operating state of the hybrid vehicle.

[0163] Further, in an optional implementation, the step of controlling the clutch to be closed can include:

[0164] obtaining an engine second target speed curve based on the output shaft speed;

[0165] controlling the engine speed to follow the output shaft speed to be stabilized in a preset second range by using a second PI torque speed control loop based on the second target speed curve;

[0166] after the speed difference between the two ends of the clutch is lower than a preset first speed difference threshold, releasing the motor speed control, and controlling the clutch to be pre-charged for a preset third time length, and increasing the clutch torque to a preset first torque range by a gradient after the pre-charging is completed;

[0167] releasing the engine speed control after the motor speed control is released;

[0168] after the speed difference between the two ends of the clutch is lower than a preset second speed difference threshold, controlling the clutch to be closed for a preset fourth time length, wherein the second speed difference threshold is smaller than the first speed difference threshold.

[0169] In the embodiment, the step of closing the clutch after the motor is restored to the non-overspeed state, specifically, after it is identified that the motor is restored to the non-overspeed state, the VCU can send a clutch state request of No request to the TCU, and the first PI torque speed control loop for controlling the engine speed is no longer activated; the engine target curve is redefined based on the output shaft speed, that is, the engine second target speed curve. The second PI torque speed control loop is activated to control the engine speed to follow the output shaft speed to be stabilized in a preset second range.

[0170] Here, the control purpose of the first PI torque speed control loop is to reduce the engine speed to a preset first range, so as to reduce the motor speed; and the control purpose of the second PI torque speed control loop is to stabilize the engine speed in a preset second range, for example, about 100 rpm, so as to close the clutch.

[0171] TCU receives the clutch state request No request sent by VCU, and after the speed difference between the two ends of the clutch is lower than the preset second speed difference threshold, the TCU can send the motor speed control request No request to the VCU, set shift_in_progress as not in progress, and send it to the VCU. At the same time, the clutch pre-charge can be controlled within a preset third time length, and after the pre-charge is completed, the clutch torque is increased to a preset first torque range; for example, the third time length can be 150 milliseconds, and the first torque range can be about 20 newton-meters. When the clutch pre-charge ends and the torque capacity reaches a calibration threshold, the TCU also needs to send the clutch slip state to the VCU. The calibration threshold is exemplarily 10 newton-meters.

[0172] After receiving the motor speed control request No request from the TCU, the VCU can no longer activate the second PI torque speed control loop; after receiving shift_in_progress as not in progress from the TCU, the VCU can set the shift permission and send it to the TCU to inform the TCU that it is no longer in the shift control state. After the speed difference between the two ends of the clutch is lower than the preset second speed difference threshold, the TCU can control the clutch to close within a preset fourth time length. For example, the second speed difference threshold can be 200 revolutions per minute; the fourth time length can be 50 milliseconds.

[0173] In addition, in the embodiment of the present application, after the motor operating state is obtained in the power split mode in the above-mentioned step 401, if the motor operating state is an overspeed state, the target operating mode is required to be switched to the series mode or the direct drive mode.

[0174] In the embodiment, the motor operating state is an overspeed state, and the target operating mode (power split mode) needs to be performed, so if the current target operating mode, the hybrid vehicle will not respond to the instruction to switch the target operating mode to the series mode or the direct drive mode.

[0175] It should be understood that the size of the serial number of each step in the above-mentioned embodiment does not mean the order of execution, and the execution order of each process should be determined according to its function and inherent logic, and should not constitute any limitation on the implementation process of the embodiment of the present application.

[0176] The following is the device embodiment of the present application. For details not described in detail, please refer to the corresponding method embodiments described above.

[0177] Figure 5 The structure schematic diagram of the control device of the vehicle provided by the embodiment of the present application is shown. For the convenience of description, only the parts related to the embodiment of the present application are shown, and the details are as follows:

[0178] As Figure 5 shown, the control device 5 of the vehicle comprises:

[0179] a state acquisition unit 51 configured to acquire a motor operating state in the power split mode;

[0180] a clutch control unit 52 configured to control the clutch to open if the motor operating state is an overspeed state;

[0181] an engine speed control unit 53 configured to control the engine speed to follow the output shaft speed to decrease to a preset first range after the clutch is opened;

[0182] a motor speed determination unit 54 configured to determine a first target motor speed based on the engine speed, wherein the first target motor speed does not exceed a preset maximum motor speed limit;

[0183] a motor speed control unit 55 configured to control the motor of the hybrid vehicle based on the first target motor speed.

[0184] Based on the second aspect, in a possible implementation, the clutch control unit 52 is specifically configured to limit the engine torque and the motor torque to zero; and control the clutch to open after the engine torque and the motor torque are zero and a preset first duration is continued.

[0185] Based on the second aspect, in a possible implementation, the engine speed control unit 53 is specifically configured to obtain an engine first target speed curve based on the output shaft speed; and control the engine speed to decrease to the preset first range by a first PI torque speed control loop based on the first target speed curve.

[0186] Based on the second aspect, in a possible implementation, the motor speed determination unit 54 is specifically configured to obtain a motor speed target value based on the engine speed, the output shaft speed and the gear speed ratio; and determine the motor speed target value that is not greater than the preset maximum motor speed limit as the first target motor speed.

[0187] Based on the second aspect, in a possible implementation, the control device 5 can further comprise:

[0188] a split mode determination unit configured to determine that the hybrid vehicle operates in the power split mode if both the target operating mode and the actual operating mode of the hybrid vehicle are the power split mode;

[0189] a switching control unit configured to prohibit the target operating mode from being switched to the series mode or the direct drive mode if the motor operating state is the overspeed state.

[0190] Based on the second aspect, in a possible implementation, the control device 5 can further comprise:

[0191] The running state determination unit is configured to determine that the motor running state is an overspeed state if the current driving mode is the preset driving mode, the absolute value of the actual motor speed is higher than the preset first speed threshold, and the front axle left-right wheel speed difference is greater than the preset calibration threshold before the state acquisition unit acquires the motor running state in the power split mode.

[0192] The running state determination unit is configured to determine that the motor running state is a non-overspeed state if the current driving mode is not the preset driving mode, or the absolute value of the actual motor speed is not higher than the preset first speed threshold, or the front axle left-right wheel speed difference is not greater than the preset calibration threshold.

[0193] In a possible implementation manner of the second aspect, the control device 5 can further include:

[0194] The state switching determination unit is configured to determine that the motor running state is switched from the overspeed state to the non-overspeed state if the second target speed is lower than the preset second speed threshold, the duration for which the second target speed is lower than the preset second speed threshold is not less than the preset second duration, and the front axle left-right wheel speed difference is not greater than the preset calibration threshold after the motor speed control unit controls the motor of the hybrid vehicle based on the first target speed. The second speed threshold is less than the maximum motor speed limit.

[0195] In a possible implementation manner of the second aspect, the clutch control unit is further configured to control the clutch to be closed if the motor running state is switched from the overspeed state to the non-overspeed state, increase the clutch torque capacity based on a preset gradient after the clutch is closed, and request the engine torque to be based on the front axle torque distribution and the motor torque to be based on the front axle torque distribution after the clutch torque capacity is increased to a preset threshold.

[0196] In a possible implementation manner of the second aspect, the clutch control unit 52 can be specifically configured to:

[0197] obtain an engine second target speed curve based on the output shaft speed;

[0198] control the engine speed to follow the output shaft speed to be stable in a preset second range by using a second PI torque speed control loop based on the second target speed curve;

[0199] release the motor speed control after the speed difference between the two ends of the clutch is lower than a preset first speed difference threshold, control the clutch to be pre-charged within a preset third duration, and increase the clutch torque to a preset first torque range by a gradient after the pre-charging is completed;

[0200] After the motor speed control is released, the engine speed control is released.

[0201] After the speed difference of the clutch is lower than a preset second speed difference threshold, the clutch is controlled to be closed within a preset fourth time length, wherein the second speed difference threshold is smaller than the first speed difference threshold.

[0202] As can be seen from the above, the motor running state is acquired in the power split mode, when the motor running state is the overspeed state, the clutch is first controlled to be opened, and the engine speed is controlled to follow the output shaft speed to decrease to a preset first range after the clutch is opened. Since the driving force cannot be transmitted to the output shaft after the clutch is opened, the output shaft speed will decrease, and the engine speed will also follow the output shaft speed to decrease. Since the engine speed and the motor speed are related due to the configuration, the motor first target speed determined based on the engine speed will decrease after the engine speed decreases, and if the motor first target speed is lower than the maximum motor speed limit of the motor, the motor of the hybrid vehicle can be controlled in speed based on the first target speed, thereby solving the problem of motor overspeed, achieving protection of the motor, and ensuring the safety of vehicle operation.

[0203] The embodiment of the present application also provides a computer program product, which has program codes, the program codes perform the steps in any one of the vehicle control method embodiments of the present application when running in a corresponding processor, controller, computing device or controller, for example Figure 4 The steps 401 to 405 shown. Those skilled in the art should understand that the method and the device proposed by the embodiment of the present application can be realized in various forms of hardware, software, firmware, special processor or combination thereof. The special processor can include application specific integrated circuit (ASIC), reduced instruction set computer (RISC) and / or field programmable gate array (FPGA). The proposed method and device are preferably realized as a combination of hardware and software. The software is preferably installed as an application program on a program storage device. It is typically a machine based on a computer platform with hardware, such as one or more central processing units (CPUs), random access memories (RAMs) and one or more input / output (I / O) interfaces. An operating system is also typically installed on the computer platform. The various processes and functions described herein can be part of the application program, or part thereof can be executed by the operating system.

[0204] Figure 6 is a schematic view of the vehicle provided by the embodiment of the present application. As Figure 6 shown, the vehicle 6 comprises a processor 60, a memory 61, and a computer program 62 stored in the memory 61 and executable on the processor 60. The processor 60 implements the steps in each of the control method embodiments described above when executing the computer program 62, for example Figure 4The steps 401-405 are shown. Alternatively, the processor 60 implements the functions of the units in the above-described apparatus embodiments when executing the computer program 62, for example Figure 5 The functions of the modules 51-55 are shown.

[0205] The computer program 62 can be divided into one or more modules / units, which are stored in the memory 61 and executed by the processor 60, to complete / execute the schemes provided in the present application. The one or more modules / units can be a series of computer program instruction segments capable of completing specific functions, which are used to describe the execution process of the computer program 62 in the controller 6.

[0206] The vehicle 6 can include, but is not limited to, the processor 60, the memory 61. Those skilled in the art can understand that the vehicle 6 can further include other components, for example, an input / output device, a network access device, a bus, etc. Figure 6 The vehicle 6 is only an example and does not constitute a limitation on the vehicle 6, and can include more or fewer components than shown, or combine certain components, or different components, for example, the vehicle can also include an input / output device, a network access device, a bus, etc.

[0207] The processor 60 can be a central processing unit (CPU), and can also be other general-purpose processors, a digital signal processor (DSP), an application specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic devices, discrete gate or transistor logic devices, discrete hardware components, etc. The general-purpose processor can be a microprocessor or the processor can also be any conventional processor.

[0208] The memory 61 can be an internal storage unit of the vehicle 6, for example, a hard disk or a memory of the vehicle 6. The memory 61 can also be an external storage device of the vehicle 6, for example, a plug-in hard disk, a smart media card (SMC), a secure digital (SD) card, a flash card, etc. Further, the memory 61 can include both the internal storage unit and the external storage device of the vehicle 6. The memory 61 is used to store the computer program and other programs and data required by the controller. The memory 61 can also be used to temporarily store data that has been output or will be output.

[0209] Those skilled in the art can clearly understand that, for the convenience and brevity of description, only the above-mentioned division of each functional unit and module is exemplified, and in actual application, the above-mentioned functions can be completed by different functional units and modules according to needs, that is, the internal structure of the device is divided into different functional units or modules to complete all or part of the functions described above. Each functional unit and module in the embodiment can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The above-mentioned integrated unit can be realized in the form of hardware or software function unit. In addition, the specific name of each functional unit and module is only for the convenience of mutual distinction, and does not limit the protection scope of the present application. The specific working process of the unit and module in the above system can refer to the corresponding process in the foregoing method embodiment, which will not be described here.

[0210] In the above embodiments, the description of each embodiment has its own emphasis, and the parts not described or recorded in detail in a certain embodiment can be referred to the related description of other embodiments.

[0211] Those of ordinary skill in the art can realize that the units and algorithm steps of each example described in combination with the embodiments disclosed herein can be realized in electronic hardware or a combination of computer software and electronic hardware. Whether the functions are executed in hardware or software depends on the specific application and design constraints of the technical solution. Professionals can use different methods to implement the described functions for each specific application, but such implementation should not be considered beyond the scope of the present application.

[0212] In the embodiments provided in the present application, it should be understood that the disclosed devices / controllers and methods can be implemented in other ways. For example, the device / controller embodiments described above are only schematic. For example, the division of the modules or units is only a logical function division, and actual implementation can have another division manner. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. In addition, the coupling or direct coupling or communication connection between the units shown or discussed can be indirect coupling or communication connection through some interface, device or unit, and can be electrical, mechanical or other forms.

[0213] The units described as separate components can or can not be physically separated, and the components shown as units can or can not be physical units, that is, they can be located in one place, or can be distributed on multiple network units. Some or all of the units can be selected according to actual needs to achieve the purpose of the embodiment.

[0214] In addition, each functional unit in each embodiment of the present application can be integrated in one processing unit, or each unit can be physically present separately, or two or more units can be integrated in one unit. The integrated unit can be realized in the form of hardware or in the form of a software functional unit.

[0215] The integrated module / unit, if realized in the form of a software functional unit and sold or used as an independent product, can be stored in a computer-readable storage medium. Based on such understanding, all or part of the processes in the above-mentioned embodiments can be implemented by a computer program instructing related hardware to complete, and the computer program can be stored in a computer-readable storage medium. When executed by a processor, the computer program can implement the steps of each vehicle anti-skid protection method embodiment. The computer program includes computer program code, which can be in the form of source code, object code, executable files, or some intermediate forms, etc. The computer-readable medium can include any entity or device capable of carrying the computer program code, recording medium, U disk, mobile hard disk, magnetic disk, optical disk, computer memory, read-only memory (ROM), random access memory (RAM), electrical carrier signal, telecommunication signal, and software distribution medium, etc. It should be noted that the computer-readable medium can include appropriate additions or subtractions according to the requirements of legislation and patent practice in the jurisdiction, for example, in some jurisdictions, according to legislation and patent practice, the computer-readable medium does not include electrical carrier signals and telecommunication signals.

[0216] In one embodiment, the present application provides a vehicle comprising a controller as described above.

[0217] In addition, the features of the embodiments shown in the drawings of the present application or mentioned in the specification of the present application are not necessarily understood as independent embodiments from each other. Rather, each feature described in one example of an embodiment can be combined with one or more other desired features from other embodiments, thereby generating other embodiments not described in words or with reference to the drawings.

[0218] The above-described embodiments are only used to illustrate the technical solutions of the present application, and not to limit them; although the present application has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that they can modify the technical solutions recorded in the foregoing embodiments, or make equivalent replacements for part of the technical features; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the spirit and scope of the technical solutions of the embodiments of the present application, and should be included in the protection scope of the present application.

Claims

1. A method for controlling a vehicle, characterized in that, The method includes: Obtain motor operating status in power split mode; If the motor is in an overspeed state, the clutch will be disengaged. After the clutch is disengaged, the engine speed is controlled to decrease to a preset first range, following the output shaft speed. The first target speed of the motor is determined based on the engine speed, wherein the first target speed does not exceed a preset maximum motor speed limit; The motor speed of the hybrid vehicle is controlled based on the first target speed.

2. The vehicle control method as described in claim 1, characterized in that, The control clutch opening includes: Limit engine torque and electric motor torque to zero; When the engine torque and motor torque are both zero, and after a preset first duration, the clutch is disengaged.

3. The vehicle control method as described in claim 1, characterized in that, The control of the engine speed to decrease to a preset first range in accordance with the output shaft speed includes: The first target engine speed curve is obtained based on the output shaft speed; Based on the first target speed curve, the engine speed is reduced to a preset first range by controlling the first PI torque speed control loop.

4. The vehicle control method as described in claim 1, characterized in that, The determination of the first target motor speed based on engine speed includes: The target value of the motor speed is obtained based on the engine speed, output shaft speed, and gear ratio; The target motor speed, which is not greater than the preset maximum motor speed limit, is determined as the first target speed.

5. The vehicle control method as described in claim 1, characterized in that, The method further includes: If both the target operating mode and the actual operating mode of the hybrid vehicle are power split mode, then the hybrid vehicle is determined to be operating in power split mode. Accordingly, after obtaining the motor operating status in the power split mode, the method further includes: If the motor is in an overspeed state, it is prohibited to switch the target operating mode to series mode or direct drive mode.

6. The vehicle control method according to any one of claims 1 to 5, characterized in that, Before obtaining the motor operating status in the power shunt mode, the following steps are also included: If the current driving mode is the preset driving mode, and the absolute value of the actual speed of the motor is higher than the preset first speed threshold, and the speed difference between the left and right wheels of the front axle is greater than the preset calibration threshold, then the motor operating state is determined to be overspeed. If the current driving mode is not the preset driving mode, or the absolute value of the actual motor speed is not higher than the preset first speed threshold, or the speed difference between the left and right front axle wheels is not higher than the preset calibration threshold, then the motor operating state is determined to be non-overspeed state.

7. The vehicle control method as described in claim 6, characterized in that, After controlling the motor speed of the hybrid vehicle based on the first target speed, the method further includes: The second target speed of the motor is obtained based on the engine speed, output shaft speed, and target gear ratio; If the second target speed is lower than the preset second speed threshold, and the duration of the speed difference between the left and right front axles is not less than the preset second duration, and the speed difference between the left and right front axles is not higher than the preset calibration threshold, then the motor operating state is determined to change from overspeed state to non-overspeed state. Wherein, the second speed threshold is less than the maximum motor speed limit.

8. The vehicle control method as described in claim 7, characterized in that, The method further includes: If the motor's operating state changes from overspeed to non-overspeed, then the clutch is controlled to close. Increase clutch torque capacity based on a preset gradient after clutch engagement; After the clutch torque capacity increases to a preset threshold, the engine torque is requested to be distributed based on the front axle torque, and the electric motor torque is requested to be distributed based on the front axle torque.

9. The vehicle control method as described in claim 8, characterized in that, The control of clutch engagement includes: The second target engine speed curve is obtained based on the output shaft speed; Based on the second target speed curve, the second PI torque speed control loop is used to control the engine speed to follow the output shaft speed and stabilize it within the preset second range. After the speed difference between the two ends of the clutch is lower than the preset first speed difference threshold, the motor speed control is released, and the clutch is pre-charged within a preset third time period. After the pre-charging is completed, the clutch torque is gradually increased to the preset first torque range. After disengaging the motor speed control, disengage the engine speed control; After the speed difference between the two ends of the clutch is lower than the preset second speed difference threshold, the clutch is controlled to close within a preset fourth time period, wherein the second speed difference threshold is less than the first speed difference threshold.

10. A vehicle, characterized in that, The vehicles include: Memory, used to store executable program code; A processor is configured to call and run the feasible program code from the memory, causing the vehicle to perform the vehicle control method as described in any one of claims 1 to 9.

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