Method for controlling vehicle reversing, vehicle and storage medium

Abstract

The present application provides a method for controlling vehicle reversing, a vehicle, and a storage medium. The method is applied to the field of vehicle technology, and includes: monitoring the actual gear position of the vehicle's gear lever when the vehicle's actual operating mode is an idle hybrid four-wheel drive mode; determining whether the vehicle meets a preset condition for switching to an idle pure electric four-wheel drive mode when the actual gear position of the gear lever is monitored to be R gear; and controlling the vehicle's actual operating mode to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode when it is determined that the vehicle meets the preset condition, so that the vehicle reverses in the idle pure electric four-wheel drive mode. The method can realize the reversing of a four-wheel drive vehicle, ensure the power performance of the vehicle when reversing, and avoid the problem of insufficient power when reversing.

Description

Technical Field

[0001] The present application relates to the field of vehicles, and more particularly, to a method for controlling vehicle reversing, a vehicle, and a storage medium in the field of vehicles. Background Art

[0002] Hybrid vehicles, due to their advantages in environmental protection, energy saving and meeting different driving needs, combined with policy support and growing market demand, are gradually becoming an important choice in the automotive market and showing strong development potential.

[0003] Hybrid vehicles have multiple gear positions, including P (park), D (drive), R (reverse), and N (neutral). When the gear lever is in R, the vehicle must reverse. Hybrid vehicles are prone to power loss during reverse, impacting the user's driving experience. Summary of the Invention

[0004] The present application provides a method for controlling vehicle reversing, a vehicle and a storage medium. The method can realize reversing of a four-wheel drive vehicle, ensure the power performance of the vehicle when reversing, and avoid the problem of insufficient power when reversing the vehicle.

[0005] In a first aspect, a method for controlling vehicle reversing is provided, which is applied to a hybrid vehicle, the vehicle including a hybrid transmission, the hybrid transmission including: a first input shaft and a second input shaft, the first input shaft being connected to a first clutch, the second input shaft being connected to a second clutch, the method comprising: when the actual operating mode of the vehicle is an idle hybrid four-wheel drive mode, monitoring the actual gear position of the vehicle's gear lever; wherein, in the idle hybrid four-wheel drive mode, the vehicle's engine is in an idle state, the first clutch is in a slipping state, the second clutch is in a closed state, the vehicle's rear-drive motor is in a driving state, and the engine drives the vehicle's front-drive motor to rotate , so that the front-wheel drive motor charges the vehicle's battery; when it is monitored that the actual gear position of the gear lever is switched to R gear, it is determined whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode; wherein, in the idle pure electric four-wheel drive mode, the vehicle's engine is in an idle state, the vehicle's front-wheel drive motor and rear-wheel drive motor are in a driving state, the first clutch and the second clutch are both in an open state, the front-wheel drive motor drives the vehicle's front wheels, and the rear-wheel drive motor drives the vehicle's rear wheels; when it is determined that the vehicle meets the preset conditions, the vehicle's actual operating mode is controlled to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode, so that the vehicle can reverse in the idle pure electric four-wheel drive mode.

[0006] In the above technical solution, when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode, after monitoring that the actual gear position of the vehicle's gear lever is switched to the R gear, it is determined that the vehicle currently needs to reverse, and after determining that the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, the vehicle is controlled to switch to the idle pure electric four-wheel drive mode, so that the vehicle reverses in the idle pure electric four-wheel drive mode. In the idle pure electric four-wheel drive mode, the front wheels of the vehicle are driven by the front drive motor and the rear wheels are driven by the rear drive motor. Even if there is no mechanical R gear in the vehicle's hybrid transmission, the vehicle can rely on the front drive motor to drive the front wheels to reverse, realizing the four-wheel drive vehicle reversing, ensuring the power performance of the vehicle when reversing, and avoiding the problem of insufficient power when reversing. In the idle pure electric four-wheel drive mode, the vehicle's engine maintains idling, that is, the engine is always maintained in a running state, so that when the vehicle switches to an operating mode that requires the use of the engine, the engine does not need to be started again, avoiding frequent start and stop of the engine, while improving the efficiency of subsequent mode switching and improving the user's car experience.

[0007] In combination with the first aspect, in some possible implementations, when it is monitored that the actual gear position of the gear lever is switched to the R gear, it is determined whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, including: when it is monitored that the actual gear position of the gear lever is switched to the R gear, it is determined whether the vehicle's hybrid transmission includes a mechanical R gear; when the hybrid transmission does not include a mechanical R gear, it is determined whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0008] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, controlling the actual operating mode of the vehicle to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode includes: controlling the first clutch and the second clutch to be open; when the second clutch is in the open state, controlling the synchronizer corresponding to the second input shaft to be engaged.

[0009] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, controlling the first clutch and the second clutch to open includes: controlling the absolute value of the actual torque of the vehicle's front drive motor and the absolute value of the actual torque of the engine to decrease; when the absolute value of the actual torque of the front drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque, controlling the first clutch and the second clutch to open.

[0010] In the above technical solution, by controlling the absolute value of the actual torque of the front-wheel drive motor to be reduced to less than or equal to the first target torque, and the absolute value of the actual torque of the engine to be reduced to less than or equal to the second target torque, the clutch is controlled to open, thereby reducing the inertia of the front-wheel drive motor and the engine after the clutch is opened, avoiding the front-wheel drive motor and the engine from spinning, reducing damage to the front-wheel drive motor and the engine, and improving the safety of vehicle operation mode switching.

[0011] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the second clutch is in an open state, the synchronizer corresponding to the second input shaft is controlled to engage gear, including: when the second clutch is in an open state, the front drive motor of the vehicle is adjusted according to the speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft; when the speed difference between the two ends of the synchronizer of the second input shaft is less than the preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage gear.

[0012] In the above technical solution, after the second clutch is opened, the rotation of the front-drive motor is controlled based on the speed of the output shaft of the hybrid transmission, which can reduce the speed difference at both ends of the synchronizer of the second input shaft. When the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage gear, thereby avoiding the severe impact between gears caused by gear switching when the speed difference is too large, protecting the hybrid transmission and other transmission system components, achieving smooth gear switching, and improving driving comfort and vehicle stability.

[0013] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage gear, including: when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the torque of the front-wheel drive motor is controlled to be reduced to the third target torque; when the torque of the front-wheel drive motor is equal to the third target torque, the synchronizer corresponding to the second input shaft is controlled to engage gear.

[0014] In this technical solution, by controlling the front-drive motor to reduce torque to the third target torque before engaging the synchronizer corresponding to the second input shaft, and only engaging the gear after confirming that the actual torque of the front-drive motor equals the third target torque, the system effectively avoids torque fluctuations and unnecessary drive output that may occur during the gear shift process. This also prevents premature torque output from the front-drive motor, which could cause the vehicle to move unprepared and affect driving safety.

[0015] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the second clutch is in an open state, the front drive motor of the vehicle is speed-regulated according to the speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft, including: when the second clutch is in an open state, sending a target gear request for the second input shaft to the TCU of the vehicle, and sending a shift permission instruction to the TCU and the FMCU of the vehicle, so that after receiving the target gear request and the shift permission instruction of the second input shaft, the TCU sends a speed control activation request and a target speed request to the FMCU; wherein the target speed request includes a target speed, and the target speed is determined based on the speed of the output shaft; after receiving the shift permission instruction and the speed control activation request, the FMCU enters a speed control mode, and after entering the speed control mode and receiving the target speed request, controls the front drive motor to rotate following the target speed to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0016] In combination with the first aspect and the above-mentioned implementation methods, in some possible implementation methods, when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the torque of the front-wheel drive motor is controlled to be reduced to the third target torque, including: when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, a speed control deactivation request is sent to the FMCU, so that the FMCU switches to the torque control mode after receiving the speed control deactivation request; when it is determined that the FMCU has switched to the torque control mode, the torque of the front-wheel drive motor is controlled to be reduced to the third target torque.

[0017] In summary, when the vehicle is in the idling hybrid four-wheel drive mode, the present application monitors that the actual gear position of the vehicle's gear lever has been switched to the R gear and the vehicle meets the preset conditions for switching to the idling pure electric four-wheel drive mode, and controls the vehicle to switch to the idling pure electric four-wheel drive mode, so that the vehicle can reverse in the idling pure electric four-wheel drive mode. Even if there is no mechanical R gear in the vehicle's hybrid transmission, the vehicle can rely on the front drive motor to drive the front wheels to reverse, realizing the four-wheel drive vehicle reverse, ensuring the power performance of the vehicle when reversing, avoiding the problem of insufficient power when reversing, and in the idling pure electric four-wheel drive mode, the vehicle's engine maintains idling, avoiding frequent starting and stopping of the engine, and improving the user's car experience. After controlling the absolute value of the actual torque of the front drive motor and the absolute value of the actual torque of the engine to be reduced, the clutch is controlled to open, avoiding the front drive motor and the engine from spinning rapidly. The speed differential between the synchronizers on the second input shaft is reduced before engaging the corresponding synchronizer. This prevents the sharp impact between gears caused by excessive speed differentials during gear shifts, protecting the hybrid transmission and other drivetrain components and enabling smooth gear shifts. The front-drive motor is also controlled to reduce torque before engaging the synchronizer on the second input shaft, preventing premature torque output from the motor, which could cause the vehicle to move unprepared and compromise driving safety.

[0018] In a second aspect, a device for controlling vehicle reversing is provided, which is applied to a hybrid vehicle, the vehicle including a hybrid transmission, the hybrid transmission including: a first input shaft and a second input shaft, the first input shaft being connected to a first clutch, the second input shaft being connected to a second clutch, the device including: a monitoring module for monitoring the actual gear position of the vehicle's gear lever when the actual operating mode of the vehicle is an idle hybrid four-wheel drive mode; wherein, in the idle hybrid four-wheel drive mode, the vehicle's engine is in an idle state, the first clutch is in a slipping state, the second clutch is in a closed state, the vehicle's rear drive motor is in a driving state, and the engine drives the vehicle's front drive motor to rotate, so that The front-wheel drive motor charges the vehicle's battery; the judgment module is used to judge whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode when it detects that the actual gear position of the gear lever is switched to R gear; wherein, in the idle pure electric four-wheel drive mode, the vehicle's engine is in an idle state, the vehicle's front-wheel drive motor and rear-wheel drive motor are in a driving state, the first clutch and the second clutch are both in an open state, the front-wheel drive motor drives the front wheels of the vehicle, and the rear-wheel drive motor drives the rear wheels of the vehicle; the control module is used to control the vehicle's actual operating mode to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode when it is determined that the vehicle meets the preset conditions, so that the vehicle can reverse in the idle pure electric four-wheel drive mode.

[0019] In combination with the second aspect, in some possible implementations, the judgment module is specifically used to, when monitoring that the actual gear position of the gear lever is switched to R gear, determine whether the vehicle's hybrid transmission includes a mechanical R gear; when the hybrid transmission does not include a mechanical R gear, determine whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0020] In combination with the second aspect and the above implementation, in some possible implementations, the control module is specifically used to control the first clutch and the second clutch to be open; when the second clutch is in the open state, control the synchronizer corresponding to the second input shaft to engage gear.

[0021] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the control module is specifically used to control the absolute value of the actual torque of the vehicle's front drive motor and the absolute value of the actual torque of the engine to decrease; when the absolute value of the actual torque of the front drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque, control the first clutch and the second clutch to open.

[0022] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the control module is specifically used to, when the second clutch is in an open state, adjust the speed of the vehicle's front drive motor according to the speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft; when the speed difference between the two ends of the synchronizer of the second input shaft is less than the preset speed difference, control the synchronizer corresponding to the second input shaft to engage gear.

[0023] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the control module is specifically used to control the torque of the front-wheel drive motor to be reduced to the third target torque when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference; and to control the synchronizer corresponding to the second input shaft to be engaged when the torque of the front-wheel drive motor is equal to the third target torque.

[0024] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the control module is specifically used to send a target gear request for the second input shaft to the TCU of the vehicle when the second clutch is in an open state, and send a shift permission instruction to the TCU and the FMCU of the vehicle, so that after receiving the target gear request and the shift permission instruction of the second input shaft, the TCU sends a speed control activation request and a target speed request to the FMCU; wherein the target speed request includes a target speed, and the target speed is determined based on the speed of the output shaft; after receiving the shift permission instruction and the speed control activation request, the FMCU enters a speed control mode, and after entering the speed control mode and receiving the target speed request, controls the front drive motor to rotate according to the target speed to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0025] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the control module is specifically used to control the torque of the front-wheel drive motor to be reduced to a third target torque when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, including: when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, sending a speed control deactivation request to the FMCU, so that the FMCU switches to the torque control mode after receiving the speed control deactivation request; when it is determined that the FMCU has switched to the torque control mode, controlling the torque of the front-wheel drive motor to be reduced to the third target torque.

[0026] In a third aspect, a vehicle is provided, comprising a memory and a processor. The memory is configured to store executable program code, and the processor is configured to retrieve and execute the executable program code from the memory, so that the vehicle executes the method of the first aspect or any possible implementation of the first aspect.

[0027] In a fourth aspect, a computer program product is provided, comprising: a computer program code, which, when executed on a computer, enables the computer to execute the method in the first aspect or any possible implementation of the first aspect.

[0028] In a fifth aspect, a computer-readable storage medium is provided, which stores a computer program code. When the computer program code runs on a computer, the computer executes the method in the above-mentioned first aspect or any possible implementation of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 This is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of the present application.

[0030] Figure 2 This is a schematic flowchart of a method for controlling vehicle reversing provided in an embodiment of the present application.

[0031] Figure 3 This is a timing diagram of switching from an idle hybrid four-wheel drive mode to an idle pure electric four-wheel drive mode provided in an embodiment of the present application.

[0032] Figure 4 It is a structural schematic diagram of a device for controlling vehicle reversing provided in an embodiment of the present application.

[0033] Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0034] The following will clearly and thoroughly describe the technical solutions in this application in conjunction with the accompanying drawings. In the description of the embodiments of this application, unless otherwise specified, " / " means or, for example, A / B can mean A or B: "and / or" in the text is only a description of the association relationship of associated objects, indicating that there can be three relationships, for example, A and / or B can mean: A exists alone, A and B exist at the same time, and B exists alone. In addition, in the description of the embodiments of this application, "multiple" means two or more than two.

[0035] In the following, the terms "first" and "second" are used for descriptive purposes only and should not be understood to imply or suggest relative importance or implicitly indicate the number of technical features indicated. Therefore, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0036] Figure 1 This is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of the present application.

[0037] For example, Figure 1 As shown, the hybrid vehicle includes: a first motor 101 , a first motor controller 102 , a hybrid transmission 103 , an engine 104 , a high-voltage battery 105 , a second motor 106 , front wheels 107 , rear wheels 108 and a differential 109 .

[0038] The first motor 101 is also called a front drive motor or a P2.5 motor. The first motor 101 drives the front wheels 107 of the vehicle through the hybrid transmission 103 or works as a generator.

[0039] The first motor controller 102 is used to control the speed, torque, and direction of the first motor 101. Specifically, by adjusting the current and voltage of the first motor 101, the speed of the first motor 101 is precisely controlled, ensuring that the first motor 101 operates within the optimal speed range under different operating conditions. Based on the vehicle's needs, the output torque of the first motor 101 is precisely controlled to ensure sufficient driving force for acceleration, climbing, and other conditions. By controlling the rotation direction of the first motor 101, the first motor 101 can rotate forward or reverse when required.

[0040] The hybrid transmission 103 is a four-speed transmission with four forward gears: 1st, 2nd, 3rd, and 4th. In some embodiments, the hybrid transmission 103 does not include a mechanical R gear for changing the direction of power transmission. The hybrid transmission specifically includes a K1 clutch 1031, a K2 clutch 1032, a first input shaft 1033, a second input shaft 1034, a first synchronizer 1035, and a second synchronizer 1036.

[0041] The K1 clutch 1031 and the K2 clutch 1032 are used to connect or disconnect the mechanical connection between the engine 104 and the input shafts of the hybrid transmission 103, namely the first input shaft 1033 and the second input shaft 1034. Specifically, the K1 clutch 1031 is connected to the first input shaft 1033. When the K1 clutch 1031 is open, the engine 104 and the first input shaft 1033 are disconnected. When the K1 clutch 1031 is closed, the engine 104 and the first input shaft 1033 are connected. The K2 clutch 1032 is connected to the second input shaft 1034. When the K2 clutch 1032 is open, the engine 104 and the second input shaft 1034 are disconnected. When the K2 clutch 1032 is closed, the engine 104 and the second input shaft 1034 are connected.

[0042] The first input shaft 1033 is also referred to as the odd-numbered shaft and includes odd gears: 1st gear and 3rd gear. The first synchronizer 1035 is used to select 1st gear or 3rd gear on the first input shaft 1033 so that the engine 104 transmits the power corresponding to 1st gear or 3rd gear. The second input shaft 1034 is also referred to as the even-numbered shaft and includes even gears: 2nd gear and 4th gear. The second synchronizer 1036 is used to select 2nd gear or 4th gear on the second input shaft 1034 so that the engine 104 transmits the power corresponding to 2nd gear or 4th gear.

[0043] The first motor 101 is also connected to the second input shaft 1034 of the hybrid transmission 103 , and the K2 clutch 1032 is also used to connect or disconnect the engine 104 from the first motor 101 .

[0044] The engine 104 is one of the power sources of the vehicle and generates power by burning fuel (such as gasoline or diesel). The power generated by the engine 104 is transmitted to the hybrid transmission 103 through the clutch, and finally drives the front wheels 107 of the vehicle.

[0045] The high-voltage battery 105 is used to supply power to the second motor 106 and the first motor 101 , so that the second motor 106 and the first motor 101 output torque to drive the vehicle.

[0046] The second motor 106 is a rear-drive motor or a P4 motor. When the second motor 106 is running, it transmits power to the rear wheels 108 of the vehicle to drive the vehicle.

[0047] The differential 109 is used to allow the left and right wheels to rotate at different speeds when the vehicle turns. Through the differential 109, the outside wheel can rotate at a faster speed and the inside wheel can rotate at a slower speed, ensuring that the vehicle turns smoothly.

[0048] In the idling hybrid four-wheel drive mode, the vehicle's K1 clutch 1031 is in a slipping state, the K2 clutch 1032 is in a closed state, the engine 104 remains in an idling state, the second motor 106 is in a driving state, the first synchronizer 1035 selects first gear on the first input shaft 1033, and the second synchronizer 1036 selects neutral gear on the second input shaft 1034. In the idling hybrid four-wheel drive mode, the engine 104 drives the first motor 101 through the K2 clutch 1032 to generate electricity. The electricity generated by the first motor 101 can charge the high-voltage battery 105. The engine 104 outputs power through the slipping K1 clutch 1031 to drive the vehicle's front wheels 107, and the second motor 106 outputs power to drive the vehicle's rear wheels 108.

[0049] The clutch being in a slipping state can be understood as: the clutch is not fully engaged, and there is a certain speed difference between the gears on both sides of the clutch.

[0050] In the idling pure electric four-wheel drive mode, the vehicle's K1 clutch 1031 is in the open state, the K2 clutch 1032 is in the open state, the engine 104 remains in the idling state, the first motor 101 and the second motor 106 are both in the driving state, the second synchronizer 1036 selects the second gear on the second input shaft 1034, the engine 104 is idling, the first motor 101 outputs power to drive the vehicle's front wheels 107, and the second motor 106 outputs power to drive the vehicle's rear wheels 108.

[0051] If the gear position of the hybrid transmission of the vehicle based on the above architecture does not include the mechanical R gear, the engine cannot participate in reversing. If the vehicle is reversing in the idle hybrid four-wheel drive mode, since the engine drives the front wheels of the vehicle in the idle hybrid four-wheel drive mode, the engine cannot participate in reversing and the front-wheel drive motor is generating electricity, the vehicle can only start reversing by driving the rear wheels of the vehicle through the rear-wheel drive motor, resulting in weak reversing power of the vehicle. For scenarios such as reversing and starting the vehicle or reversing uphill, the vehicle is prone to slipping if it is driven only by the rear wheels, resulting in problems with starting or climbing the slope, affecting the user's driving experience.

[0052] Based on this, the present application proposes a method for controlling vehicle reversing to increase the power of the vehicle when reversing and improve the user's driving experience.

[0053] Figure 2 This is a schematic flow chart of a method for controlling vehicle reversing provided by an embodiment of the present application. The method is applied to a vehicle including Figure 1 The vehicle includes a hybrid transmission 103, which includes a first input shaft 1033 and a second input shaft 1034. The first input shaft 1033 is connected to a first clutch, and the second input shaft is connected to a second clutch. Figure 1 The K1 clutch 1031 in the second clutch is Figure 1 K2 clutch 1032 in.

[0054] For example, Figure 2 As shown, the method 200 includes:

[0055] Step 201: When the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode, monitoring the actual gear position of the vehicle's gear lever; wherein, in the idle hybrid four-wheel drive mode, the vehicle's engine is in an idle state, the first clutch is in a slipping state, the second clutch is in a closed state, the vehicle's rear drive motor is in a driving state, and the engine drives the vehicle's front drive motor to rotate, so that the front drive motor charges the vehicle's battery;

[0056] Step 202: When the actual gear position of the gear lever is detected to be R, determining whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode; wherein, in the idle pure electric four-wheel drive mode, the vehicle's engine is in an idle state, the vehicle's front drive motor and rear drive motor are in a driving state, the first clutch and the second clutch are both in an open state, the front drive motor drives the vehicle's front wheels, and the rear drive motor drives the vehicle's rear wheels;

[0057] Step 203 , when it is determined that the vehicle meets the preset conditions, the actual operating mode of the vehicle is controlled to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode, so that the vehicle reverses in the idle pure electric four-wheel drive mode.

[0058] exist Figure 2 In the embodiment shown, when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode, after monitoring that the actual gear position of the vehicle's gear lever is switched to the R gear, it is determined that the vehicle currently needs to reverse, and after determining that the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, the vehicle is controlled to switch to the idle pure electric four-wheel drive mode, so that the vehicle reverses in the idle pure electric four-wheel drive mode. In the idle pure electric four-wheel drive mode, the front wheels of the vehicle are driven by the front drive motor and the rear wheels are driven by the rear drive motor. Even if there is no mechanical R gear in the vehicle's hybrid transmission, the vehicle can rely on the front drive motor to drive the front wheels to reverse, realizing the four-wheel drive vehicle reversing, ensuring the power performance of the vehicle when reversing, and avoiding the problem of insufficient power when reversing. In the idle pure electric four-wheel drive mode, the engine of the vehicle maintains idling, that is, the engine is always maintained in a running state, so that when the vehicle switches to an operating mode that requires the use of the engine, the engine does not need to be started again, avoiding frequent starting and stopping of the engine, while improving the efficiency of subsequent mode switching and improving the user's car experience.

[0059] Below Figure 2 The specific implementation of each step in the embodiment shown is described in detail:

[0060] In step 201, in the idle hybrid four-wheel drive mode, the vehicle's engine is idling, and the engine outputs power to the vehicle's front wheels to drive the vehicle. The vehicle's rear-wheel drive motor is running, and the rear-wheel drive motor outputs power to the vehicle's rear wheels to drive the vehicle.

[0061] The actual gear position of the vehicle's gear lever is manually selected by the driver, usually through a physical gear lever or electronic button / knob. The gear lever gear positions include: P (Park), D (Drive), R (Reverse), N (Neutral), and many others.

[0062] P is Park, the gear used when the vehicle is stopped and is typically used to lock the wheels. When the gear lever is in P, the vehicle is parked. D is Drive, used for normal vehicle movement (i.e., forward travel). When the gear lever is in D, the hybrid transmission automatically selects the appropriate forward gear (such as 1st, 2nd, 3rd, or 4th) based on the operating mode, vehicle speed, and load to provide optimal power output and fuel economy. R is Reverse, used for reverse driving. When the gear lever is in R, the front or rear drive motor reverses, generating power that rotates the front or rear wheels in the opposite direction, thereby moving the vehicle backward. N is Neutral, which disconnects the power connection between the engine and the wheels. When the gear lever is in N, the hybrid transmission does not transmit engine power to the wheels, allowing the vehicle to coast without power.

[0063] The actual gear position of the vehicle's gear lever is the most direct indicator of the driver's driving intent, allowing the vehicle to promptly adjust power output accordingly. Vehicles are typically in idling hybrid four-wheel drive mode when parking. If the vehicle needs to park sideways or reverse into a garage, the driver typically switches the gear lever between D and R to continuously adjust the vehicle's angle and control parking. Therefore, when the vehicle's actual operating mode is idling hybrid four-wheel drive, it is necessary to monitor the actual gear position of the vehicle's gear lever.

[0064] In step 201, when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode, if the actual gear position of the vehicle's gear lever is detected to be R, it can be determined that the vehicle currently needs to reverse, and it can be determined that the vehicle needs to switch the driving mode to the idle pure electric four-wheel drive mode to achieve the four-wheel drive vehicle reverse. Therefore, after monitoring that the actual gear position of the vehicle's gear lever is switched to R, it is necessary to determine whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0065] The preset conditions for switching to the idle pure electric four-wheel drive mode may include: the remaining power of the high-voltage battery is greater than a preset power (e.g., 15%), the power of the high-voltage battery is greater than a preset power, etc. For example, when the remaining power of the high-voltage battery is greater than 15% of the preset power, and the power of the high-voltage battery is greater than the preset power, it can be determined that the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0066] Among them, the preset power level is a minimum power threshold set in advance to ensure that the vehicle has sufficient power to complete the current driving task or at least can safely switch back to other modes (such as series mode or parallel mode) to avoid battery damage caused by deep discharge of the high-voltage battery.

[0067] The preset power is a pre-set minimum power threshold to ensure the high-voltage battery can provide sufficient power when needed. The power output of a high-voltage battery can be affected by temperature, aging, or other factors. By setting a minimum power threshold, the vehicle ensures that the battery is performing well before entering the idle electric all-wheel drive mode, thereby optimizing energy management and the driving experience.

[0068] In one possible implementation, when it is monitored that the actual gear position of the gear lever is switched to the R gear, it is determined whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, including: when it is monitored that the actual gear position of the gear lever is switched to the R gear, it is determined whether the hybrid transmission of the vehicle includes a mechanical R gear; when the hybrid transmission does not include a mechanical R gear, it is determined whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0069] Among them, the mechanical R gear, also known as the reverse gear, is a dedicated gear in the hybrid transmission. It is used to realize the reversing function by changing the rotation direction of the internal gears of the hybrid transmission to make the vehicle move backward.

[0070] In the idle hybrid four-wheel drive mode, the front wheels of the vehicle are driven by the engine output power. When the hybrid transmission includes a mechanical R gear, after the actual gear position of the gear lever is switched to R gear, the hybrid transmission can be shifted to the mechanical R gear to change the direction of the engine output power, causing the front wheels of the vehicle to rotate in the opposite direction, thereby moving the vehicle backward.

[0071] When the hybrid transmission does not include a mechanical R gear, after the actual gear position of the gear lever is switched to R gear, the hybrid transmission cannot change the direction of the engine output power, and the engine cannot reverse. Therefore, the engine cannot participate in reverse in the idling hybrid four-wheel drive mode. In the idling pure electric four-wheel drive mode, the front drive motor outputs power to drive the front wheels. The front drive motor can reverse the output power to drive the front wheels to rotate in the opposite direction, thereby moving the vehicle backward. Therefore, when it is determined that the hybrid transmission does not include a mechanical R gear, in order to ensure the vehicle's four-wheel drive reverse, it is possible to determine whether the vehicle meets the preset conditions for switching to the idling pure electric four-wheel drive mode.

[0072] In step 203, when the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, it can be determined that the vehicle can currently switch to the idle pure electric four-wheel drive mode. At this time, the actual operating mode of the vehicle is controlled to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode.

[0073] In the idle pure electric four-wheel drive mode, the engine is idling, the front-wheel drive motor and the rear-wheel drive motor are both reversed, the front-wheel drive motor drives the front wheels of the vehicle, and the rear-wheel drive motor drives the rear wheels of the vehicle to achieve four-wheel drive reverse.

[0074] In one possible implementation, controlling the actual operating mode of the vehicle to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode includes: controlling both the first clutch and the second clutch to open; and when the second clutch is in the open state, controlling the synchronizer corresponding to the second input shaft to engage gear.

[0075] Specifically, in idling hybrid four-wheel drive mode, the vehicle's first clutch is in a slipping state and the second clutch is in a closed state. The engine drives the vehicle's front wheels through the slipping first clutch, and drives the front-wheel drive motor to generate electricity through the closed second clutch. In idling pure electric four-wheel drive mode, both the first and second clutches are open. Therefore, when controlling the actual operating mode of the vehicle from idling hybrid four-wheel drive mode to idling pure electric four-wheel drive mode, both the first and second clutches need to be controlled to be open.

[0076] In the idle hybrid four-wheel drive mode, the engine transmits power to the output shaft of the hybrid transmission through the first input shaft connected to the first clutch, so the synchronizer corresponding to the first input shaft is in odd gear. The first input shaft is the odd shaft, which includes odd gears 1 and 3. The synchronizer corresponding to the first input shaft is Figure 1 Synchronizer 1035 in the idling hybrid four-wheel drive mode. In the idle hybrid four-wheel drive mode, the front motor is connected to the second input shaft through the second clutch. At this time, the front motor is driven by the engine to generate electricity and does not output power. Therefore, the synchronizer corresponding to the second input shaft is in neutral. The second input shaft is the even-numbered shaft, which includes the even-numbered gears 2 and 4. The synchronizer corresponding to the second input shaft is Figure 1 Synchronizer 1036 in.

[0077] In idle pure electric four-wheel drive mode, the front-wheel drive motor is running. The front-wheel drive motor is connected to the second input shaft and needs to transmit power to the output shaft of the hybrid transmission through the second input shaft. Therefore, the second input shaft needs to be engaged. The gear engagement operation must be performed with the clutch open. Therefore, when the actual operating mode of the vehicle is switched from idle hybrid four-wheel drive mode to idle pure electric four-wheel drive mode, after confirming that the second clutch is open, the synchronizer corresponding to the second input shaft needs to be engaged. The gear engaged by the synchronizer corresponding to the second input shaft is the even-numbered gear 2nd or 4th gear.

[0078] As in the above embodiment, when the vehicle is driving in a parking scenario, the vehicle speed is relatively low. The gear position of the synchronizer corresponding to the first input shaft may be 1st gear, and the even-numbered gear position of the synchronizer corresponding to the second input shaft may be 2nd gear.

[0079] In one possible implementation, controlling both the first clutch and the second clutch to open includes: controlling the absolute value of the actual torque of the vehicle's front-wheel drive motor and the absolute value of the actual torque of the engine to decrease; and controlling both the first clutch and the second clutch to open when the absolute value of the actual torque of the front-wheel drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque.

[0080] As in the above-described embodiment, in the idle hybrid four-wheel drive mode, the engine is in operation, that is, the engine outputs a certain torque. The engine transmits part of the output torque to the wheels through the slipping first clutch, and also transmits part of the output torque to the front-drive motor through the closed second clutch, controlling the front-drive motor to generate power. That is, the front-drive motor also has a certain torque at this time. In some embodiments, because the front-drive motor is currently generating power, the torque of the front-drive motor at this time is referred to as negative torque. After both the first and second clutches are opened, the front-drive motor and the engine are unloaded, and the front-drive motor and the engine are prone to overspin.

[0081] In order to prevent the front-wheel drive motor and the engine from spinning wildly after both the first clutch and the second clutch are opened, after determining that the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode, the absolute value of the actual torque of the front-wheel drive motor and the absolute value of the actual torque of the engine can be controlled to decrease first. After the absolute value of the actual torque of the front-wheel drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque, the first clutch and the second clutch are controlled to open.

[0082] The first target torque is a pre-set torque that prevents the front-drive motor from spinning out of control. It is usually slightly greater than 0 NM (Newton-meter), for example, 3 NM. In this case, the absolute value of the front-drive motor's actual torque needs to be controlled to be less than or equal to 3 NM to keep the actual torque of the front-drive motor close to 0 NM. The second target torque is usually slightly greater than the first target torque. When the second target torque can specifically be an idle load torque at which the engine can maintain a relatively low idle speed, for example, 5 NM, the actual torque of the engine needs to be controlled to be less than or equal to 5 NM.

[0083] In some embodiments, Figure 1The control units in the hybrid vehicle shown may include: a hybrid transmission control unit (TCU), a hybrid control unit (HCU), an engine management system (EMS), and a front motor control unit (FMCU). The control method may be executed by a control unit in the vehicle, such as the HCU, TCU, EMS, or FMCU.

[0084] Specifically, when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode, if it is monitored that the actual gear position of the gear lever has become the R gear, it is determined that the actual operating mode of the vehicle needs to be switched from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode. Assuming that the first input shaft (i.e., the odd-numbered shaft) of the vehicle is in 1st gear in the idle hybrid four-wheel drive mode, the HCU of the vehicle sends a signal to the TCU that the target gear position of the odd shaft is 1st gear, the target gear position of the even shaft is 2nd gear, the target direct drive gear is 1st gear, the Idle H-AWD (idle hybrid four-wheel drive) mode is exited, the Idle E-AWD (idle pure electric four-wheel drive) mode is activated, the K2 clutch (i.e., the second clutch) is closed, and the K1 clutch (i.e., the first clutch) is slipped, so that the TCU can determine the current state of the vehicle. At the same time, the HCU controls the absolute values ​​of the front-wheel drive motor's actual torque and the engine's actual torque to approach 0 NM. When the absolute values ​​of the motor's actual torque fall below the first target torque by 3 NM and the engine's actual torque falls below the second target torque by 5 NM, the HCU sends a K2 clutch open request signal and a K1 clutch open request signal to the TCU. Upon receiving these signals, the TCU controls the K2 clutch and the K1 clutch to open.

[0085] In some embodiments, controlling both the first clutch and the second clutch to open includes: first controlling the second clutch to open and then controlling the first clutch to open.

[0086] Specifically, the first clutch is used to output power to the vehicle's front wheels, while the second clutch is used to generate electricity for the front-wheel drive motor. Controlling the second clutch to open first—that is, the clutch that doesn't output power to the wheels—facilitates switching back to idle hybrid four-wheel drive mode after the second clutch is opened and then the user shifts the gear lever to D. In this case, only the second clutch needs to be closed, improving mode switching efficiency.

[0087] Figure 3This is a timing diagram of switching from an idle hybrid four-wheel drive mode to an idle pure electric four-wheel drive mode provided in an embodiment of the present application.

[0088] For example, Figure 3 As shown, the switching of the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode includes four stages, namely: stage one (idle hybrid four-wheel drive mode), stage two (clutch control stage), stage three (gear control stage), and stage four (idle pure electric four-wheel drive mode).

[0089] In Phase 1, also known as Idle Hybrid AWD mode, the vehicle's engine is idling. To deliver power, the engine rotates at a relatively high idle speed. The engine outputs a certain torque as negative torque to the P2.5 motor, driving it to generate electricity. The P2.5 motor also rotates at a certain speed. The K1 clutch (first clutch) is in a slipping state, while the K2 clutch (second clutch) is in a closed state. The K1 clutch state request is a slipping request, while the K2 clutch state request is a closed request. The first synchronizer S1 is in a gear-up completion state, while the second synchronizer S2 is in a gear-down completion state. The target gear request for the odd-numbered axles is 1st gear (Gear 1), and the target gear request for the even-numbered axles is neutral (Gear N). The target operating mode request is Idle Hybrid AWD mode (Idle H-AWD).

[0090] In Phase 2, the target operating mode request changes to Idle E-AWD mode, the engine speed decreases, and the absolute values ​​of the engine torque and the front-wheel drive motor torque decrease. After the engine speed drops to the target idle speed corresponding to Idle E-AWD mode and the absolute values ​​of the engine torque and the front-wheel drive motor torque drop to 0 NM, the K1 clutch state request changes to an open request, and the K2 clutch state request changes to an open request. After the K1 and K2 clutch state requests change to open requests, the actual state of the K1 clutch changes to open, and the actual state of the K2 clutch changes to open.

[0091] In the above method, by controlling the absolute value of the actual torque of the front-wheel drive motor to be reduced to less than or equal to the first target torque, and the absolute value of the actual torque of the engine to be reduced to less than or equal to the second target torque, the clutch is controlled to open, thereby reducing the inertia of the front-wheel drive motor and the engine after the clutch is opened, avoiding the front-wheel drive motor and the engine from spinning, reducing damage to the front-wheel drive motor and the engine, and improving the safety of vehicle operation mode switching.

[0092] In a possible implementation, when the second clutch is in the open state, controlling the synchronizer corresponding to the second input shaft to engage a gear includes the following steps S11 to S12:

[0093] S11, when the second clutch is in an open state, the front drive motor of the vehicle is adjusted in speed according to the rotation speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0094] like Figure 1 As shown, the second input shaft includes a second synchronizer 1036 between the even-numbered gears 2 and 4, i.e., the synchronizer for the second input shaft. Before controlling the synchronizer corresponding to the second input shaft to engage a gear, the speed difference across the second synchronizer 1036 needs to be reduced to ensure safe gear engagement and avoid gear shock.

[0095] When the second clutch is in the open state, the two ends of the synchronizer of the second input shaft are respectively the front-wheel drive motor and the output shaft of the hybrid transmission. The output shaft of the hybrid transmission is connected to the front wheels of the vehicle. If the vehicle is currently moving, the output shaft of the hybrid transmission has a certain speed. At this time, the speed of the front-wheel drive motor can be adjusted based on the speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0096] In one possible implementation, when the second clutch is in an open state, the front drive motor of the vehicle is regulated according to the speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft, including: when the second clutch is in an open state, sending a target gear request for the second input shaft to the TCU of the vehicle, and sending a shift permission instruction to the TCU and the FMCU of the vehicle, so that after receiving the target gear request and the shift permission instruction of the second input shaft, the TCU sends a speed control activation request and a target speed request to the FMCU; wherein the target speed request includes a target speed, and the target speed is determined based on the speed of the output shaft; after receiving the shift permission instruction and the speed control activation request, the FMCU enters a speed control mode, and after entering the speed control mode and receiving the target speed request, controls the front drive motor to rotate according to the target speed to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0097] After the second clutch is opened, the second input shaft of the vehicle is disconnected from the engine. At this time, it can be determined that the second input shaft can start to shift gears. Therefore, after determining that the second clutch is opened, the HCU sends a target gear request for the second input shaft to the TCU, and sends a gear shift permission instruction to the TCU and the vehicle's FMCU.

[0098] After receiving the target gear request and shift permission command for the second input shaft from the HCU, the TCU determines that the vehicle currently permits the synchronizer corresponding to the second input shaft to engage in gear. Controlling the synchronizer corresponding to the second input shaft to engage in gear requires reducing the speed differential across the synchronizer of the second input shaft to less than a preset speed differential. As in the aforementioned embodiment, when the second clutch is in the open state, the synchronizer of the second input shaft is connected to the output shaft of the hybrid transmission and the front-drive motor, respectively. At this point, the TCU can obtain the speed of the output shaft of the hybrid transmission and add a calibration value to the speed of the output shaft of the hybrid transmission to obtain the target speed. The target speed is the target speed of the front-drive motor. When the front-drive motor is rotating at the target speed, the speeds of the synchronizer of the second input shaft are the same.

[0099] After determining the target speed, the TCU sends a speed control activation request and a target speed request to the FMCU. The target speed request includes the target speed. After receiving the shift permission command from the HCU and the speed control activation request from the TCU, the FMCU enters speed control mode. In this mode, the FMCU controls the front-wheel drive motor based on the target speed. After entering speed control mode and receiving the target speed request from the TCU, the FMCU controls the front-wheel drive motor to rotate at the target speed to reduce the speed difference between the two ends of the synchronizer on the second input shaft.

[0100] S12: When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage a gear.

[0101] The preset speed difference is the maximum speed difference to ensure that the second input shaft can be safely shifted into gear. When the speed difference at both ends of the synchronizer of the second input shaft, i.e., the second synchronizer 1036, is less than the preset speed difference, it can be determined that the synchronizer corresponding to the second input shaft can be safely and smoothly controlled to shift into gear 2 or 4.

[0102] The vehicle may have speed sensors at both ends of the synchronizer on the second input shaft. During the process of adjusting the speed of the front-drive motor, the TCU can obtain the speeds collected by the sensors at both ends of the synchronizer on the second input shaft, calculate the speed difference, and determine whether the speed difference is less than a preset speed difference, such as 50 rpm. If the speed difference is less than the preset speed difference of 50 rpm, the TCU controls the synchronizer corresponding to the second input shaft to engage a gear.

[0103] The target gear request of the second input shaft may further include a target even gear (eg, 2nd gear) to be engaged, so that the TCU controls the synchronizer corresponding to the second input shaft to engage the target even gear.

[0104] For example, Figure 3As shown, after the second clutch is opened, the target gear request of the even-numbered axis in stage three becomes 2nd gear (Gear 2), the second synchronizer S2 becomes synchronized state, the speed of the front-wheel drive motor begins to decrease, and after the speed of the front-wheel drive motor drops to the target speed of 2nd gear, the second synchronizer S2 becomes in gear-moving state, and after the gear-moving is completed, the second synchronizer S2 becomes gear-moving completed state.

[0105] like Figure 3 As shown, in stage three, after the second synchronizer S2 changes to the gear-up completion state, the torque of the front-wheel drive motor begins to increase until the torque of the front-wheel drive motor increases to the required torque of the front axle.

[0106] like Figure 3 As shown, in stage 4, that is, the idle pure electric four-wheel drive mode, the engine maintains the target idle speed corresponding to the idle pure electric four-wheel drive mode. The front drive motor maintains the target speed of 2nd gear and outputs the front axle required torque to the front wheels of the vehicle. The first and second clutches are both in the open state, the first and second synchronizers maintain the gear-up completion state, the odd-numbered axle target gear request remains in 1st gear, the even-numbered axle target gear request remains in 2nd gear, and the target operating mode request maintains the idle pure electric four-wheel drive mode.

[0107] In the above method, after the second clutch is opened, the rotation of the front-wheel drive motor is controlled based on the speed of the output shaft of the hybrid transmission, which can reduce the speed difference at both ends of the synchronizer of the second input shaft. When the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage gear, thereby avoiding the severe impact between gears caused by gear switching when the speed difference is too large, protecting the hybrid transmission and other transmission system components, achieving smooth gear switching, and improving driving comfort and vehicle stability.

[0108] In one possible implementation, when the speed difference between the two ends of the synchronizer of the second input shaft is less than the preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage gear, including: when the speed difference between the two ends of the synchronizer of the second input shaft is less than the preset speed difference, controlling the torque of the front-drive motor to reduce to the third target torque; when the torque of the front-drive motor is equal to the third target torque, controlling the synchronizer corresponding to the second input shaft to engage gear.

[0109] It can be understood that when the above-mentioned TCU controls the synchronizer corresponding to the second input shaft to engage gear, the FMCU enters the speed control mode to adjust the speed of the front-wheel drive motor. At this time, the front-wheel drive motor has a certain torque. At this time, the actual operation mode of the vehicle has not switched to the idle pure electric four-wheel drive mode, that is, the HCU has not yet issued an instruction to control the output torque of the front-wheel drive motor. After the synchronizer corresponding to the second input shaft is engaged, the actual operation mode of the vehicle will switch to the idle pure electric four-wheel drive mode.

[0110] To prevent the front-wheel drive motor from already outputting torque before the HCU issues a command to control the front-wheel drive motor's output torque after switching to the idle pure electric four-wheel drive mode, the front-wheel drive motor's torque needs to be reduced to a third target torque before the synchronizer corresponding to the second input shaft is engaged. The third target torque can be 0 NM to ensure that the front-wheel drive motor does not output torque after switching to the idle pure electric four-wheel drive mode.

[0111] After determining that the actual torque of the front-drive motor is equal to the third target torque 0 NM, the synchronizer corresponding to the second input shaft is controlled to shift into gear.

[0112] This method effectively avoids torque fluctuations and unnecessary drive output that may occur during the gear shift process by controlling the front-drive motor to reduce torque to the third target torque before the synchronizer corresponding to the second input shaft engages a gear. The method then confirms that the front-drive motor's actual torque equals the third target torque before engaging the gear. This prevents premature torque output from the front-drive motor, which could cause the vehicle to move unprepared and compromise driving safety.

[0113] In one possible implementation, when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, the torque of the front-wheel drive motor is controlled to be reduced to the third target torque, including: when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, a speed control deactivation request is sent to the FMCU, so that the FMCU switches to the torque control mode after receiving the speed control deactivation request; when it is determined that the FMCU switches to the torque control mode, the torque of the front-wheel drive motor is controlled to be reduced to the third target torque.

[0114] Specifically, when the speed difference across the synchronizer of the second input shaft is less than a preset speed difference, it can be determined that the second input shaft can be safely controlled to engage a gear, and it is no longer necessary to control the front-drive motor based on the target speed to reduce the speed difference across the synchronizer of the second input shaft. At this point, the TCU sends a speed control deactivation request to the FMCU, causing the FMCU to determine that it is no longer necessary to control the front-drive motor based on the target speed.

[0115] After the FMCU determines that the front-wheel drive motor is no longer controlled based on the target speed, it switches to a torque control model. In this mode, the FMCU controls the front-wheel drive motor based on the target torque. At this point, the vehicle still requires no output torque, so the front-wheel drive motor's torque is reduced to the third target torque of 0 Nm.

[0116] After the TCU detects that the speed difference between the two ends of the second synchronizer S2 is less than the preset speed difference of 50rpm and the torque of the front drive motor is reduced to 0Nm, it controls the synchronizer corresponding to the second input shaft to shift into gear through the second synchronizer S2.

[0117] In some embodiments, after determining that the second synchronizer S2 has been engaged, the HCU further sends a shift disallowed instruction to each control unit and controls the vehicle to reverse in the Idle E-AWD mode.

[0118] In summary, when the vehicle is in the idling hybrid four-wheel drive mode, the present application monitors that the actual gear position of the vehicle's gear lever has been switched to the R gear and the vehicle meets the preset conditions for switching to the idling pure electric four-wheel drive mode, and controls the vehicle to switch to the idling pure electric four-wheel drive mode, so that the vehicle can reverse in the idling pure electric four-wheel drive mode. Even if there is no mechanical R gear in the vehicle's hybrid transmission, the vehicle can rely on the front drive motor to drive the front wheels to reverse, realizing the four-wheel drive vehicle reverse, ensuring the power performance of the vehicle when reversing, avoiding the problem of insufficient power when reversing, and in the idling pure electric four-wheel drive mode, the vehicle's engine maintains idling, avoiding frequent starting and stopping of the engine, and improving the user's car experience. After controlling the absolute value of the actual torque of the front drive motor and the absolute value of the actual torque of the engine to be reduced, the clutch is controlled to open, avoiding the front drive motor and the engine from spinning rapidly. The speed differential between the synchronizers on the second input shaft is reduced before engaging the corresponding synchronizer. This prevents the sharp impact between gears caused by excessive speed differentials during gear shifts, protecting the hybrid transmission and other drivetrain components and enabling smooth gear shifts. The front-drive motor is also controlled to reduce torque before engaging the synchronizer on the second input shaft, preventing premature torque output from the motor, which could cause the vehicle to move unprepared and compromise driving safety.

[0119] Figure 4 It is a structural schematic diagram of a device for controlling vehicle reversing provided in an embodiment of the present application.

[0120] The invention is applied to a hybrid vehicle, the vehicle includes a hybrid transmission, and the hybrid transmission includes: a first input shaft and a second input shaft, the first input shaft is connected to a first clutch, and the second input shaft is connected to a second clutch.

[0121] For example, Figure 4 As shown, the apparatus 400 includes:

[0122] The monitoring module 401 is configured to monitor the actual gear position of the vehicle's gear lever when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode; wherein, in the idle hybrid four-wheel drive mode, the vehicle's engine is in an idle state, the first clutch is in a slipping state, the second clutch is in a closed state, the vehicle's rear-drive motor is in a driving state, and the engine drives the vehicle's front-drive motor to rotate, so that the front-drive motor charges the vehicle's battery;

[0123] The judgment module 402 is configured to judge whether the vehicle satisfies a preset condition for switching to the idle pure electric four-wheel drive mode when the actual gear position of the gear lever is detected to be the R gear; wherein, in the idle pure electric four-wheel drive mode, the vehicle's engine is in an idle state, the vehicle's front drive motor and rear drive motor are in a driving state, the first clutch and the second clutch are both in an open state, the front drive motor drives the vehicle's front wheels, and the rear drive motor drives the vehicle's rear wheels;

[0124] The control module 403 is used to control the actual operation mode of the vehicle to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode when it is determined that the vehicle meets the preset conditions, so that the vehicle can reverse in the idle pure electric four-wheel drive mode.

[0125] In one possible implementation, the judgment module 402 is specifically used to determine whether the vehicle's hybrid transmission includes a mechanical R gear when it is monitored that the actual gear position of the gear lever is switched to R gear; if the hybrid transmission does not include a mechanical R gear, determine whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode.

[0126] In a possible implementation, the control module 403 is specifically configured to control both the first clutch and the second clutch to be open; and when the second clutch is in the open state, control the synchronizer corresponding to the second input shaft to engage gear.

[0127] In one possible implementation, the control module 403 is specifically used to control the absolute value of the actual torque of the vehicle's front-wheel drive motor and the absolute value of the actual torque of the engine to decrease; when the absolute value of the actual torque of the front-wheel drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque, control the first clutch and the second clutch to open.

[0128] In one possible implementation, the control module 403 is specifically used to adjust the speed of the vehicle's front-wheel drive motor according to the rotational speed of the output shaft of the hybrid transmission when the second clutch is in an open state, so as to reduce the speed difference between the two ends of the synchronizer of the second input shaft; and control the synchronizer corresponding to the second input shaft to engage gear when the speed difference between the two ends of the synchronizer of the second input shaft is less than the preset speed difference.

[0129] In one possible implementation, the control module 403 is specifically used to control the torque of the front-drive motor to be reduced to a third target torque when the speed difference at both ends of the synchronizer of the second input shaft is less than a preset speed difference; and to control the synchronizer corresponding to the second input shaft to be engaged when the torque of the front-drive motor is equal to the third target torque.

[0130] In one possible implementation, the control module 403 is specifically used to send a target gear request for the second input shaft to the vehicle's TCU when the second clutch is in an open state, and send a shift permission instruction to the TCU and the vehicle's FMCU, so that after receiving the target gear request and the shift permission instruction for the second input shaft, the TCU sends a speed control activation request and a target speed request to the FMCU; wherein the target speed request includes a target speed, and the target speed is determined based on the speed of the output shaft; after receiving the shift permission instruction and the speed control activation request, the FMCU enters a speed control mode, and after entering the speed control mode and receiving the target speed request, controls the front drive motor to rotate according to the target speed to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

[0131] In one possible implementation, the control module 403 is specifically used to control the torque of the front-wheel drive motor to be reduced to a third target torque when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, including: when the speed difference at both ends of the synchronizer of the second input shaft is less than the preset speed difference, sending a speed control deactivation request to the FMCU, so that the FMCU switches to the torque control mode after receiving the speed control deactivation request; when it is determined that the FMCU has switched to the torque control mode, controlling the torque of the front-wheel drive motor to be reduced to the third target torque.

[0132] Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0133] For example, Figure 5 As shown, the vehicle 500 includes: a memory 501 and a processor 502, wherein the memory 501 stores an executable program code 5011, and the processor 502 is used to call and execute the executable program code 5011 to perform a method for controlling vehicle reversing.

[0134] In addition, an embodiment of the present application also protects a device, which may include a memory and a processor, wherein the memory stores executable program code, and the processor is used to call and execute the executable program code to perform a method for controlling vehicle reversing provided in an embodiment of the present application.

[0135] In this embodiment, the device can be divided into functional modules based on the above-described method examples. For example, each functional module can be mapped to a specific functional module, or two or more functions can be integrated into a single processing module. The integrated module can be implemented in hardware. It should be noted that the module division in this embodiment is illustrative and represents only a logical functional division. In actual implementation, other division methods may be used.

[0136] In the case of dividing each functional module into corresponding functional modules, the device may further include a monitoring module, a judgment module, a control module, etc. It should be noted that all relevant contents of each step involved in the above method embodiment can be referred to the functional description of the corresponding functional module and will not be repeated here.

[0137] It should be understood that the device provided in this embodiment is used to execute the above-mentioned method of controlling vehicle reversing, and thus can achieve the same effect as the above-mentioned implementation method.

[0138] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is used in a vehicle, the processing module may be used to control and manage the vehicle's movements, while the storage module may be used to support the vehicle's execution of relevant program codes.

[0139] The processing module may be a processor or controller that implements or executes the various exemplary logic blocks, modules, and circuits described in conjunction with the present disclosure. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of a digital signal processing (DSP) and a microprocessor, and the storage module may be a memory.

[0140] In addition, the device provided in the embodiments of the present application can specifically be a chip, component or module, and the chip may include a connected processor and memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute a method for controlling vehicle reversing provided in the above embodiment.

[0141] This embodiment also provides a computer-readable storage medium, which stores computer program code. When the computer program code runs on a computer, the computer executes the above-mentioned related method steps to implement a method for controlling vehicle reversing provided in the above embodiment.

[0142] This embodiment further provides a computer program product. When the computer program product is run on a computer, the computer is caused to execute the above-mentioned related steps to implement a method for controlling vehicle reversing provided in the above embodiment.

[0143] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment are all used to execute the corresponding methods provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding methods provided above, and will not be repeated here.

[0144] Through the description of the above implementation methods, technical personnel in the relevant field can understand that for the convenience and simplicity of description, only the division of the above-mentioned functional modules is used as an example. In actual applications, the above-mentioned functions can be distributed and completed by different functional modules as needed, that is, the internal structure of the device can be divided into different functional modules to complete all or part of the functions described above.

[0145] In the embodiments provided in this application, it should be understood that the disclosed devices and methods can be implemented in other ways. For example, the device embodiments described above are merely schematic. For example, the division of modules or units is only a logical function division. In actual implementation, there may be other division methods, such as multiple units or components can be combined or integrated into another device, or some features can be ignored or not executed. Another point is that the mutual coupling or direct coupling or communication connection shown or discussed can be through some interfaces, indirect coupling or communication connection of devices or units, which can be electrical, mechanical or other forms.

[0146] The above content is merely a specific embodiment of the present application, but the scope of protection of the present application is not limited thereto. Any changes or substitutions that can be easily conceived by a person skilled in the art within the technical scope disclosed in this application should be included in the scope of protection of the present application. Therefore, the scope of protection of the present application should be based on the scope of protection of the claims.

Claims

1. A method for controlling a vehicle to reverse, characterized in that: A hybrid vehicle is applied, the vehicle including a hybrid transmission, the hybrid transmission including: a first input shaft and a second input shaft, the first input shaft being connected to a first clutch, the second input shaft being connected to a second clutch, the method comprising: monitoring the actual gear position of the gear lever of the vehicle when the actual operating mode of the vehicle is the idle hybrid four-wheel drive mode; wherein, in the idle hybrid four-wheel drive mode, the engine of the vehicle is in an idle state, the first clutch is in a slipping state, the second clutch is in a closed state, the rear-drive motor of the vehicle is in a driving state, and the engine drives the front-drive motor of the vehicle to rotate, so that the front-drive motor charges the battery of the vehicle; When it is detected that the actual gear position of the gear lever is switched to the R gear, determining whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode; wherein, in the idle pure electric four-wheel drive mode, the engine of the vehicle is in an idle state, the front drive motor and the rear drive motor of the vehicle are in a driving state, the first clutch and the second clutch are both in an open state, the front drive motor drives the front wheels of the vehicle, and the rear drive motor drives the rear wheels of the vehicle; When it is determined that the vehicle meets the preset conditions, the actual operating mode of the vehicle is controlled to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode, so that the vehicle reverses in the idle pure electric four-wheel drive mode.

2. The method according to claim 1, characterized in that When the actual gear position of the gear lever is detected to be the R gear, determining whether the vehicle meets the preset conditions for switching to the idle pure electric four-wheel drive mode includes: When it is detected that the actual gear position of the gear lever is switched to the R gear, determining whether the hybrid transmission of the vehicle includes a mechanical R gear; In a case where the hybrid transmission does not include the mechanical R gear, it is determined whether the vehicle meets a preset condition for switching to an idle pure electric four-wheel drive mode.

3. The method according to claim 1 or 2, characterized in that The controlling the actual operating mode of the vehicle to switch from the idle hybrid four-wheel drive mode to the idle pure electric four-wheel drive mode includes: controlling the first clutch and the second clutch to open; When the second clutch is in an open state, the synchronizer corresponding to the second input shaft is controlled to engage gear.

4. The method according to claim 3, characterized in that The controlling the first clutch and the second clutch to be opened includes: controlling the absolute value of the actual torque of the front drive motor and the absolute value of the actual torque of the engine of the vehicle to decrease; When the absolute value of the actual torque of the front-drive motor is less than or equal to the first target torque and the absolute value of the actual torque of the engine is less than or equal to the second target torque, the first clutch and the second clutch are both controlled to be open.

5. The method according to claim 3, characterized in that When the second clutch is in the open state, controlling the synchronizer corresponding to the second input shaft to engage a gear includes: When the second clutch is in an open state, the vehicle front drive motor is speed-regulated according to the rotational speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft; When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, the synchronizer corresponding to the second input shaft is controlled to engage a gear.

6. The method according to claim 5, characterized in that When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, controlling the synchronizer corresponding to the second input shaft to engage a gear comprises: When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, controlling the torque of the front-drive motor to be reduced to a third target torque; When the torque of the front-drive motor is equal to the third target torque, the synchronizer corresponding to the second input shaft is controlled to engage gear.

7. The method according to claim 5, characterized in that When the second clutch is in the open state, regulating the speed of the vehicle front drive motor according to the rotational speed of the output shaft of the hybrid transmission to reduce the speed difference between the two ends of the synchronizer of the second input shaft includes: When the second clutch is in the open state, a target gear request for the second input shaft is sent to a TCU of the vehicle, and a shift permission instruction is sent to the TCU and the FMCU of the vehicle, so that after receiving the target gear request for the second input shaft and the shift permission instruction, the TCU sends a speed control activation request and a target speed request to the FMCU; wherein the target speed request includes a target speed, and the target speed is determined based on the speed of the output shaft; After receiving the gear shift permission instruction and the speed control activation request, the FMCU enters the speed control mode, and after entering the speed control mode and receiving the target speed request, controls the front drive motor to rotate according to the target speed to reduce the speed difference between the two ends of the synchronizer of the second input shaft.

8. The method according to claim 7, characterized in that When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, controlling the torque of the front-drive motor to reduce to a third target torque includes: When the speed difference between the two ends of the synchronizer of the second input shaft is less than a preset speed difference, a speed control deactivation request is sent to the FMCU, so that the FMCU switches to the torque control mode after receiving the speed control deactivation request; When it is determined that the FMCU is switched to the torque control mode, the torque of the front drive motor is controlled to be reduced to a third target torque.

9. A vehicle, characterized in that: The vehicle comprises: a memory for storing executable program code; A processor is configured to call and run the executable program code from the memory, so that the vehicle executes the method according to any one of claims 1 to 8.

10. A computer-readable storage medium, characterized in that The computer-readable storage medium stores a computer program, and when the computer program is executed, the method according to any one of claims 1 to 8 is implemented.

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