A method, device, vehicle and storage medium for controlling mode switching

Abstract

The present application provides a method, device, vehicle and storage medium for controlling mode switching, the method comprising: in the process of switching the vehicle from the series mode to the direct drive mode, when it is determined that the second clutch is open, controlling the second input shaft to be engaged in an even gear; if it is detected that the gear position of the second input shaft is neutral, determining that the even gear on the second input shaft is unavailable; when it is determined that the even gear on the second input shaft is unavailable, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, controlling the second clutch to close; when the second clutch is in a closed state, controlling the first clutch to open, so that the vehicle switches back from the direct drive mode to the series mode. The method can automatically switch back to the series mode when the vehicle is stuck during the mode change process, ensuring the normal power output of the vehicle.

Description

Technical Field

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

[0002] Hybrid vehicles are becoming an important choice in the automotive market and showing strong development potential due to their advantages in environmental protection, energy saving and meeting different driving needs, combined with policy support and market demand growth. Hybrid vehicles usually include multiple driving modes, such as direct drive mode, pure electric mode, series mode, etc. Multiple modes are usually switched under certain conditions to ensure the driving performance and driving experience of the vehicle.

[0003] In the prior art, when switching from the series mode to the direct drive mode, when switching to the second input shaft to engage gear, if the even gears on the second input shaft are not available, the vehicle will be stuck in an intermediate state, resulting in abnormal vehicle power output. Summary of the invention

[0004] The present application provides a method, device, vehicle and storage medium for controlling mode switching. The method can automatically switch back to the series mode when the vehicle becomes stuck during the mode change process, thereby ensuring normal power output of the vehicle.

[0005] In a first aspect, a method for controlling mode switching is provided, which is applied to a hybrid vehicle, the vehicle comprising a hybrid transmission, the hybrid transmission comprising: 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: in the process of the vehicle switching from a series mode to a direct drive mode, when it is determined that the second clutch is open, controlling the second input shaft to engage in an even gear; if it is detected that the gear position of the second input shaft is neutral, determining that the even gear on the second input shaft is unavailable; when it is determined that the even gear on the second input shaft is unavailable, if it is monitored that the vehicle meets a preset condition for switching to the series mode, controlling the second clutch to close; when the second clutch is in a closed state, controlling the first clutch to open, so that the vehicle switches back from the direct drive mode to the series mode.

[0006] In the above technical solution, when the vehicle switches from the series mode to the direct drive mode, if it is determined that the even gear on the second input shaft is unavailable, it is determined that the vehicle mode change is stuck, that is, the vehicle is currently in an intermediate state. At this time, after detecting that the vehicle meets the preset conditions for switching to the series mode, the vehicle is directly controlled to switch back to the series mode, ensuring the normal output of the vehicle power and avoiding the problem of the vehicle being stuck in the intermediate state, resulting in the problem of limited system output power. And directly switching back to the series mode before the vehicle switches the mode is simple and efficient, ensuring the normal driving of the vehicle.

[0007] In combination with the first aspect, in certain possible implementations, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, the second clutch is controlled to close, including: if it is monitored that the vehicle meets the preset conditions for switching to the series mode, the front drive motor of the vehicle is controlled to rotate based on the target speed; the difference between the actual speed of the front drive motor and the target speed is calculated; when the difference is less than the preset difference, the second clutch is controlled to close.

[0008] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, when the second clutch is in a closed state, the first clutch is controlled to open, including: when the second clutch is in a closed state, controlling the torque output from the vehicle's engine to the front wheels to be reduced; when the torque output from the vehicle's engine to the front wheels is reduced to a preset torque, controlling the first clutch to open.

[0009] In combination with the first aspect and the above-mentioned implementation method, when the second clutch is in a closed state, the torque output from the vehicle's engine to the front wheels is controlled to be reduced, including: when the second clutch is in a closed state, the output torque of the engine is output as a power generation torque to the front drive motor of the vehicle, so that the torque output from the engine to the front wheels is reduced, and the front drive motor generates electricity based on the power generation torque.

[0010] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, when it is determined that the second clutch is open, before controlling the second input shaft to shift into an even gear, the method also includes: when it is determined that the vehicle needs to switch from series mode to direct drive mode, judging whether the vehicle is in a target operating condition; wherein the target operating condition is a condition in which the accelerator pedal depth of the vehicle is greater than a preset depth; when it is determined that the vehicle is in the target operating condition, detecting whether the first input shaft of the vehicle is shifted into an odd gear; when the first input shaft is shifted into an odd gear, controlling the first clutch to be in a slipping state; when the first clutch is in a slipping state, controlling the engine output torque of the vehicle so that the first clutch transmits the engine output torque to the wheels of the vehicle in a slipping state, and when the first clutch is in a slipping state, controlling the second clutch to open.

[0011] In the above technical solution, the target working condition is a working condition where the accelerator pedal depth is greater than a preset depth, i.e., a high throttle working condition. When it is determined that the vehicle needs to switch from the series mode to the direct drive mode under the high throttle working condition, after detecting that the odd-numbered shaft of the vehicle is in gear, the vehicle directly controls the first clutch to be in a slipping state, and controls the engine to output torque when the first clutch is in a slipping state, which can effectively reduce the delay in the power output of the vehicle during the mode switching process. In this embodiment, when switching from the series mode to the direct drive mode under the high throttle working condition, the clutch is controlled to start outputting power when it is in a slipping state. Compared with the prior art in which the clutch is controlled to be closed before power output, the control of the first clutch slipping does not require the speed difference at both ends of the clutch to be less than a certain value, so the clutch can be controlled to be in a slipping state after determining that the odd-numbered shaft is in gear, and then the engine is controlled to output power, which shortens the time of engine power output during the mode switching process and can effectively reduce the delay in the power output of the vehicle.

[0012] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, when the first clutch is in a slipping state, the engine output torque of the vehicle is controlled so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state, including: when it is determined that the first clutch is in a slipping state, setting the actual operating mode of the vehicle to a direct drive mode; when the actual operating mode of the vehicle is set to a direct drive mode, controlling the engine output torque of the vehicle, and controlling the clutch pressure of the first clutch to increase as the engine output torque increases, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state.

[0013] In combination with the first aspect and the above-mentioned implementation methods, in certain possible implementation methods, when the first clutch is in a slipping state, the second clutch of the vehicle is controlled to open, including: when it is determined that the first clutch is in a slipping state, controlling the absolute value of the torque of the front drive motor of the vehicle to decrease; when it is determined that the absolute value of the actual torque of the front drive motor is reduced to the target torque, controlling the second clutch to open.

[0014] In the above technical solution, when the vehicle switches from the series mode to the direct drive mode, the torque output by the engine has been controlled to be transmitted to the front wheels of the vehicle through the first clutch when the first clutch is in a slip state. At this time, opening the second clutch can prevent the engine from outputting torque to the front drive motor through the second clutch to generate electricity, thereby ensuring the driving power of the vehicle. And when the absolute value of the actual torque of the front drive motor is reduced to the target torque, the second clutch is controlled to open, thereby ensuring the safety of the front drive motor and avoiding the problem of the front drive motor spinning rapidly after the second clutch is opened when the actual torque of the front drive motor is not reduced.

[0015] In summary, in the present application, when the vehicle is stuck during the process of switching from the series mode to the direct drive mode, the vehicle is directly controlled to switch back to the series mode, which ensures the normal output of the vehicle power and avoids the problem that the vehicle is stuck in the middle state, resulting in the problem of limited system output power. And directly switching back to the series mode before the vehicle switches modes is simple and efficient, ensuring the normal driving of the vehicle. And when it is determined that the vehicle is in a scenario where the series mode switches to the direct drive mode under a large throttle condition, it can be determined that the speed difference between the two ends of the first clutch is large. At this time, when the first clutch is controlled to be in a slip state, the engine output power is controlled. Compared with the method of controlling the clutch to close and then controlling the engine output torque in the prior art, the engine power output time during the mode switching process is shortened, which can effectively reduce the delay in the vehicle power output. When the first clutch is in a slip state, opening the second clutch can avoid the engine outputting torque to the front drive motor through the second clutch to generate electricity, thereby ensuring the power of the vehicle. And when the absolute value of the actual torque of the front-drive motor is reduced to the target torque, the second clutch is controlled to open, which ensures the safety of the front-drive motor and avoids the problem of the front-drive motor spinning after the second clutch is opened when the actual torque of the front-drive motor is not reduced.

[0016] In a second aspect, a device for controlling mode switching 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 first control module, for controlling the second input shaft to engage in an even gear when determining that the second clutch is open during the process of the vehicle switching from a series mode to a direct drive mode; a determination module, for determining that the even gear on the second input shaft is unavailable if it is detected that the gear position of the second input shaft is neutral; a second control module, for controlling the second clutch to close when determining that the even gear on the second input shaft is unavailable and monitoring that the vehicle meets preset conditions for switching to the series mode; and a third control module, for controlling the first clutch to open when the second clutch is in a closed state, so as to switch the vehicle back to the series mode from the direct drive mode.

[0017] In combination with the second aspect, in certain possible implementations, the second control module is specifically used to, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, control the front drive motor of the vehicle to rotate based on the target speed; calculate the difference between the actual speed of the front drive motor and the target speed; and control the second clutch to close when the difference is less than the preset difference.

[0018] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the third control module is specifically used to control the reduction of the torque output by the vehicle's engine to the front wheels when the second clutch is in a closed state; and to control the opening of the first clutch when the torque output by the vehicle's engine to the front wheels is reduced to a preset torque.

[0019] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the third control module 404 is specifically used to output the output torque of the engine as the generating torque to the front drive motor of the vehicle when the second clutch is in a closed state, so as to reduce the torque output by the engine to the front wheels and enable the front drive motor to generate electricity based on the generating torque.

[0020] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the device also includes: a judgment module, which is used to judge whether the vehicle is in a target operating condition when it is determined that the vehicle needs to switch from a series mode to a direct drive mode; wherein the target operating condition is a condition in which the accelerator pedal depth of the vehicle is greater than a preset depth; a detection module, which is used to detect whether the first input shaft of the vehicle is engaged in an odd gear when it is determined that the vehicle is in the target operating condition; a fourth control module, which is used to control the first clutch to be in a slipping state when the first input shaft is engaged in an odd gear; and a fifth control module, which is used to control the engine output torque of the vehicle when the first clutch is in a slipping state, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state, and controls the second clutch to open when the first clutch is in a slipping state.

[0021] In combination with the second aspect and the above-mentioned implementation methods, in certain possible implementation methods, the fifth control module is specifically used to, when it is determined that the first clutch is in a slipping state, set the actual operating mode of the vehicle to a direct drive mode; when the actual operating mode of the vehicle is set to the direct drive mode, control the engine output torque of the vehicle, and control the clutch pressure of the first clutch to increase as the engine output torque increases, so that the first clutch transmits the engine output torque to the wheels of the vehicle in a slipping state.

[0022] In combination with the second aspect and the above-mentioned implementation methods, in some possible implementation methods, the fifth control module is specifically used to control the absolute value of the torque of the vehicle's front drive motor to decrease when it is determined that the first clutch is in a slipping state; and to control the second clutch to open when it is determined that the absolute value of the actual torque of the front drive motor is reduced to the target torque.

[0023] In a third aspect, a vehicle is provided, comprising a memory and a processor. The memory is used to store executable program code, and the processor is used to call and run the executable program code from the memory, so that the vehicle executes the method in the first aspect or any possible implementation of the first aspect.

[0024] 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.

[0025] 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 manner of the first aspect. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] Figure 1 It is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of the present application.

[0027] Figure 2 It is a flowchart of a method for controlling mode switching provided in an embodiment of the present application.

[0028] Figure 3 It is a timing diagram of switching from a series mode to a direct drive mode provided in an embodiment of the present application.

[0029] Figure 4 It is a structural schematic diagram of a control mode switching device provided in an embodiment of the present application.

[0030] Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application. DETAILED DESCRIPTION

[0031] The technical solution in the present application will be described clearly and in detail below in conjunction with the accompanying drawings. In the description of the embodiments of the present 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 the present application, "multiple" means two or more than two.

[0032] In the following, the terms "first" and "second" are used for descriptive purposes only and are not to be understood as suggesting or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0033] Figure 1 It is a schematic diagram of the architecture of a hybrid vehicle provided in an embodiment of the present application.

[0034] 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 .

[0035] 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.

[0036] 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 accurately controlled to ensure that the first motor 101 operates within the optimal speed range under different working conditions. According to the needs of the vehicle, the output torque of the first motor 101 is accurately controlled to ensure that the vehicle obtains sufficient driving force under acceleration, climbing, etc. By controlling the rotation direction of the first motor 101, it is ensured that the first motor 101 can rotate forward or reverse when needed.

[0037] The hybrid transmission 103 is a 4-speed transmission, including 4 forward gears, namely 1st gear, 2nd gear, 3rd gear and 4th gear. 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 .

[0038] 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 shaft of the hybrid transmission 103, and the input shaft of the hybrid transmission is 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 in an open state, the engine 104 and the first input shaft 1033 are disconnected. When the K1 clutch 1031 is in a closed state, 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 in an open state, the engine 104 and the second input shaft 1034 are disconnected. When the K2 clutch 1032 is in a closed state, the engine 104 and the second input shaft 1034 are connected.

[0039] The first input shaft 1033 is also called an odd-numbered shaft, including odd-numbered gears: 1st gear and 3rd gear. The first synchronizer 1035 is used to select the 1st gear or 3rd gear on the first input shaft 1033, so that the engine 104 transmits the power corresponding to the 1st gear or 3rd gear. The second input shaft 1034 is also called an even-numbered shaft, including even-numbered gears: 2nd gear and 4th gear. The second synchronizer 1036 is used to select the 2nd gear or 4th gear on the second input shaft 1034, so that the engine 104 transmits the power corresponding to the 2nd gear or 4th gear.

[0040] 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 .

[0041] 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.

[0042] 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.

[0043] 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.

[0044] 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 outer wheels can rotate at a faster speed, and the inner wheels can rotate at a slower speed, ensuring that the vehicle turns smoothly.

[0045] In the series mode, the K1 clutch 1031 of the vehicle is in an open state, the K2 clutch 1032 is in a closed state, the engine 104 is running, and the engine 104 drives the first motor 101 to run and generate electricity through the K2 clutch 1032, and the high-voltage battery 105 supplies power to the second motor 106, so that the second motor 106 drives the rear wheel 108 of the vehicle. That is, in the series mode, the electric energy generated by the front drive motor can charge the high-voltage battery. The front wheel 107 of the vehicle is in a driven state, the rear drive motor runs to output power, and the rear wheel 108 is driven to drive the vehicle to move.

[0046] In direct drive mode, the engine 104 and the motor drive the vehicle together. Specifically, the K1 clutch 1031 or the K2 clutch 1032 of the vehicle is in a closed state, the engine 104 is running, the engine 104 drives the front wheels 107 of the vehicle through the K1 clutch 1031 or the K2 clutch 1032, and the high-voltage battery 105 supplies power to the second motor 106 so that the second motor 106 drives the rear wheels 108 of the vehicle. When the vehicle is in 1st gear or 3rd gear, the K1 clutch 1031 is closed; when the vehicle is in 2nd gear or 4th gear, the K2 clutch 1032 is closed.

[0047] In direct drive mode, the state of the front drive motor is related to the current vehicle speed, which is described below:

[0048] In direct drive mode, if the current vehicle speed is less than or equal to the preset speed, the front drive motor is in a non-working state. The non-working state can be understood as a 0 torque state, that is, the front drive motor does not output torque. In the non-working state, the front drive motor neither participates in the driving of the front wheels nor charges the battery. In direct drive mode, if the current vehicle speed is greater than the preset speed, the front drive motor is in a power generation state or a driving state. When the front drive motor is in a power generation state, the front drive motor is used to charge the high-voltage battery. When the front drive motor is in a driving state, the engine and the front drive motor are used to jointly drive the front wheels. Among them, the preset speed is usually small.

[0049] In the prior art, there are Figure 1 When a vehicle with the architecture shown switches from series mode to direct drive mode and switches to the second input shaft to engage gear, if the even gears on the second input shaft are not available, the vehicle will be stuck in an intermediate state, resulting in abnormal vehicle power output.

[0050] Based on this, the present application proposes a method for switching control modes, so that when the vehicle gets stuck during the mode change process, it can automatically switch back to the series mode, thereby ensuring the normal power output of the vehicle.

[0051] Figure 2 is a flow chart of a method for controlling mode switching provided in an embodiment of the present application. The method is applied to include Figure 1The vehicle includes a hybrid transmission, 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. Figure 1 The odd-numbered axis 1033 in the second input axis is Figure 1 The even-numbered shaft 1034, the first clutch is Figure 1 The K1 clutch 1031 in the second clutch is Figure 1 K2 clutch 1032 in.

[0052] For example, Figure 2 As shown, the method 200 includes:

[0053] Step 201, when the vehicle is switched from the series mode to the direct drive mode, if it is determined that the second clutch is open, the second input shaft is controlled to be engaged in an even gear;

[0054] Step 202, if it is detected that the gear position of the second input shaft is neutral, then determining that the even-numbered gear on the second input shaft is unavailable;

[0055] Step 203, when it is determined that the even-numbered gear on the second input shaft is unavailable, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, controlling the second clutch to close;

[0056] Step 204 , when the second clutch is in a closed state, control the first clutch to open so that the vehicle switches back from the direct drive mode to the series drive mode.

[0057] exist Figure 2 In the embodiment shown, when the vehicle switches from the series mode to the direct drive mode, if it is determined that the even gear on the second input shaft is unavailable, it is determined that the vehicle mode change is stuck, that is, the vehicle is currently in an intermediate state. At this time, after detecting that the vehicle meets the preset conditions for switching to the series mode, the vehicle is directly controlled to switch back to the series mode, ensuring the normal output of the vehicle power and avoiding the problem of the vehicle being stuck in the intermediate state, resulting in the problem of limited system output power. And directly switching back to the series mode before the vehicle switches the mode is simple and efficient, ensuring the normal driving of the vehicle.

[0058] In step 201, the even-numbered gears include the 2nd gear and the 4th gear, and controlling the second input shaft to shift into the even-numbered gears means controlling the second input shaft to shift into the 2nd gear or the 4th gear.

[0059] The vehicle switches from the series mode to the direct drive mode, that is, the actual operation mode before the vehicle switches modes is the series mode, and the target operation mode of the vehicle is the direct drive mode. In the series mode, the first clutch is in an open state, the second clutch is in a closed state, and the second input shaft is in neutral. If the second input shaft of the vehicle needs to be in the 2nd gear or the 4th gear during the switching from the series mode to the direct drive mode, the second clutch needs to be in an open state. Therefore, the second input shaft can be controlled to be in the 2nd gear or the 4th gear when the second clutch is determined to be in an open state.

[0060] In a possible implementation, when it is determined that the second clutch is open, before controlling the second input shaft to engage in an even-numbered gear, the method further includes the following steps S11 to S14:

[0061] S11 determines whether the vehicle is in a target operating condition when it is determined that the vehicle needs to switch from the series mode to the direct drive mode.

[0062] The target operating condition is a condition in which the accelerator pedal depth of the vehicle is greater than a preset depth.

[0063] The preset depth is used to determine whether the vehicle is in high-throttle driving. When it is determined that the vehicle needs to switch from series mode to direct drive mode, the vehicle's current accelerator pedal depth can be obtained. When the accelerator pedal depth is greater than the preset depth (for example, 90%), it is determined that the vehicle is in the target operating condition.

[0064] In some embodiments, the target operating condition may also be a condition where the vehicle speed is less than a preset speed and the accelerator pedal depth is greater than a preset depth. The preset speed is used to determine whether the vehicle is in a low-speed driving state, and the preset speed is, for example, 15 kph, and the preset depth is, for example, 90%. When the current speed of the vehicle is less than the preset speed of 15 kph and the accelerator pedal depth is greater than 90% of the preset depth, it can be determined that the vehicle is in a low-speed high-throttle operating condition, that is, it is determined that the vehicle is in a target operating condition. The mode switching method in the embodiments shown below is more effective when used in a target operating condition of low speed and high throttle.

[0065] In some embodiments, the scenario in which the vehicle switches from series mode to direct drive mode under the target operating condition can be defined as a preset scenario, and the vehicle's current speed, accelerator pedal depth, actual operating mode and target operating mode are obtained. Based on the vehicle speed, accelerator pedal depth, actual operating mode and target operating mode, it is determined whether the vehicle is in the preset scenario. When it is determined that the vehicle is in the preset scenario, subsequent mode change operations are performed.

[0066] Specifically, when the current speed of the vehicle is less than the preset speed, the accelerator pedal depth is greater than the preset depth, the actual operation mode is the series mode and the target operation mode is the direct drive mode, it is determined that the vehicle is in the preset scenario.

[0067] In the actual driving process of the vehicle, when the vehicle is starting or going uphill, the vehicle may be in the above-mentioned preset scenario.

[0068] The target operating mode can be determined based on the current operating parameters of the vehicle, or based on the mode switching instruction of the user. It is understandable that when the vehicle is in the series mode and detects that the accelerator pedal depth is greater than the preset depth and the power of the high-voltage battery is greater than the preset power, it can automatically trigger the switch from the series mode to the direct drive mode, and at this time it can be determined that the target operating mode is the direct drive mode. When the user needs the vehicle to switch to the direct drive mode, a mode switching instruction carrying the target operating mode as the direct drive mode can be sent to the vehicle, and at this time the vehicle can determine the target operating mode based on the instruction.

[0069] In some embodiments, a low-speed high-throttle mode switching flag is provided in the vehicle, and a condition for activating the low-speed high-throttle mode switching flag is provided, and the activation condition includes, for example: the current speed of the vehicle is less than the preset speed, the accelerator pedal depth is greater than the preset depth, the actual operation mode is the series mode, and the target operation mode is the direct drive mode. The low-speed high-throttle mode switching flag is activated when the current speed of the vehicle is less than the preset speed, the accelerator pedal depth is greater than the preset depth, the actual operation mode is the series mode, and the target operation mode is the direct drive mode. Therefore, when it is determined that the low-speed high-throttle mode switching flag is activated, it can be determined that the vehicle is in the preset scene.

[0070] In some embodiments, the vehicle is further provided with a condition for inactivation of the low-speed high-throttle mode switching flag, and the inactivation condition includes, for example: the target operation mode is not the direct drive mode, the actual operation mode is not the series mode, the vehicle speed is higher than the preset speed, and the accelerator pedal depth is lower than the preset depth. When the vehicle satisfies any one of the following conditions: the target operation mode is not the direct drive mode, the actual operation mode is not the series mode, the vehicle speed is higher than the preset speed, and the accelerator pedal depth is lower than the preset depth, the low-speed high-throttle mode switching flag is not activated.

[0071] In some embodiments, when it is determined that the low-speed high-throttle mode switch flag is activated, if it is detected that the vehicle meets any one of the conditions that the target operation mode is not the direct drive mode, the actual operation mode is not the series mode, the vehicle speed is higher than the preset speed, and the accelerator pedal depth is lower than the preset depth, it is still determined that the low-speed high-throttle mode switch flag is activated, that is, it is still determined that the vehicle is in the preset scenario, so that the vehicle continues to complete the mode switch.

[0072] It is understandable that when it is determined that the low-speed high-throttle mode switch flag is activated, the vehicle has usually sent a request signal for the relevant mode switch and is ready to start switching from the series mode to the direct drive mode. If it is detected at this time that the vehicle meets the condition that the low-speed high-throttle mode switch flag is not activated, the low-speed high-throttle mode switch flag is still determined to be activated to ensure that the vehicle completes the triggered mode switching process to avoid stopping the process halfway through, which may cause a logical error in the vehicle.

[0073] S12, when it is determined that the vehicle is in the target operating condition, detecting whether the first input shaft of the vehicle is engaged in an odd gear.

[0074] Among them, odd gears include 1st gear and 3rd gear. Detecting whether the first input shaft of the vehicle is in odd gears means detecting whether the first input shaft of the vehicle is in 1st gear or 3rd gear. Figure 1 The first input axis 1033 in the embodiment may also be defined as an odd-numbered axis.

[0075] It is understandable that when the vehicle is running in series mode, the first clutch is in an open state, that is, the first clutch Figure 1 The K1 clutch 1031 in Figure 1 As shown, the first input shaft 1033 is connected to the first clutch 1031. To facilitate subsequent mode switching, the vehicle usually shifts the odd-numbered shafts into gear in advance in the series mode to shorten the time required for subsequent mode switching.

[0076] When the odd-numbered shaft is engaged, the gear position to be engaged of the first input shaft can generally be determined based on the vehicle speed. For example, when the vehicle speed is less than or equal to the vehicle speed threshold of 60 kph, the gear position to be engaged of the first input shaft can be determined to be the 1st gear, and when the vehicle speed is greater than the vehicle speed threshold of 60 kph, the gear position to be engaged of the first input shaft can be determined to be the 3rd gear.

[0077] Exemplarily, the target operating condition currently in which the vehicle is located is the low-speed, high-throttle operating condition in the above-mentioned embodiment, and the vehicle speed is usually less than the vehicle speed threshold. At this time, the first input shaft will be shifted into the 1st gear. Therefore, when it is determined that the vehicle is in a scenario where it switches from the series mode to the direct drive mode under the target operating condition, it can be detected whether the first input shaft of the vehicle is shifted into the 1st gear.

[0078] In some embodiments, Figure 1The control unit in the hybrid vehicle shown may include: a hybrid transmission controller (Transmission Control Unit, TCU), a vehicle controller (Hybrid Control Unit, HCU), an EMS (Engine Management System), and a FMCU (Front Motor Control Unit). The execution subject of the control method may be a control unit in the vehicle, such as the above-mentioned HCU or TCU or EMS or FMCU.

[0079] In some embodiments, when it is detected that the vehicle has not engaged the first input shaft in advance, the first input shaft can be controlled to engage the gear. The specific process of controlling the first input shaft to engage the gear includes: when the HCU determines that the vehicle needs to switch from the series mode to the direct drive mode under the target operating condition of low speed and high throttle, the HCU sends a target operation mode request, an odd-axis target gear request, and an even-axis target gear request to the TCU of the vehicle, so that when the TCU receives the target operation mode request, the odd-axis target gear request, and the even-axis target gear request, the first input shaft is controlled to engage the gear and the second input shaft is controlled to disengage the gear; wherein the target operation mode carried by the target operation mode request is the direct drive mode, the target gear carried by the odd-axis target gear request is the 1st gear or the 3rd gear, and the target gear carried by the even-axis target gear request is the neutral gear.

[0080] In some embodiments, the HCU also sends a direct drive target gear request to the TCU, where the target gear carried in the direct drive target gear request is 1st gear or 3rd gear, so that the TCU determines that the actual gear of the vehicle in the direct drive mode is 1st gear or 3rd gear.

[0081] Figure 3 It is a timing diagram of switching from a series mode to a direct drive mode provided in an embodiment of the present application.

[0082] For example, Figure 3 As shown, the switching from the series mode to the direct drive mode includes four stages, namely: stage one (series mode), stage two (gear control stage), stage three (clutch control stage), and stage four (direct drive mode).

[0083] In stage one, that is, in series mode, the vehicle's engine rotates at a certain speed, the speed of the hybrid transmission input shaft (i.e., odd-numbered shaft) is zero, and the engine outputs a certain torque as the negative torque of the P2.5 motor, driving the P2.5 motor to generate electricity. The front axle demand torque and the actual K1 clutch torque are both zero. At this time, the vehicle is driven by the rear-drive motor. The K1 clutch (first clutch) is in the open state, and the K2 clutch (second clutch) is in the closed state. The state request of the K1 clutch is an open request, and the state request of the K2 clutch is a closed request. Synchronizer 1 (i.e. Figure 1 The first synchronizer 1035) and synchronizer 2 (ie Figure 1 The second synchronizer 1036 in the transmission is in the gear disengagement completion state. The odd-numbered axis target gear position request, the even-numbered axis target gear position request and the actual target gear position request are all neutral (Gear N), and the target operation mode request is the series mode.

[0084] In phase 2, the target gear request of the odd-numbered axle changes to 1st gear (Gear 1), and the target gear request of the even-numbered axle remains in neutral. The state of synchronizer 1 changes from synchronized state to gear in progress and then gear completed, so as to control the odd-numbered axle to engage in 1st gear, and the actual target gear request is 1st gear. The state of synchronizer 2 remains in the gear disengagement completion state. The front axle torque demand gradually increases, usually to the front axle torque demand corresponding to the actual gear of the vehicle in direct drive mode (e.g. 1st gear). The target operating mode request changes from series mode to direct drive mode.

[0085] S13, when the first input shaft is engaged in an odd-numbered gear, the first clutch is controlled to be in a slipping state.

[0086] The slip state refers to the relative sliding between the friction plate and the flywheel during the clutch engagement process, which occurs when the clutch is disengaged and fully engaged. In the slip state, the speeds of the two ends of the clutch may be inconsistent.

[0087] It is understandable that the first clutch is in the open state in the series mode, and when the series mode is switched to the direct drive mode, the first clutch is usually closed so that the engine transmits power to the front wheels of the vehicle through the first clutch and the 1st gear or the 3rd gear. Since the vehicle is in the target working condition of high throttle or low speed high throttle, the speeds at both ends of the first clutch are inconsistent and the speed difference is large. Therefore, controlling the first clutch to close at this time means controlling the first clutch to be in a slip state first, and then controlling the first clutch to close after the speed difference at both ends of the first clutch is less than a certain value.

[0088] Controlling the first clutch to be in a slipping state includes: the HCU sends a first clutch closing request to the TCU, so that after the TCU receives the first clutch closing request and determines that the first input shaft is engaged in the first gear, the first clutch is controlled to complete pre-filling of oil within a calibrated time (for example, within 150ms), so as to control the first clutch to be in a slipping state. The TCU can also send a signal that the first clutch is in a slipping state to the HCU after the first clutch completes pre-filling of oil. The slipping state is an intermediate state of the first clutch in the process of controlling the first clutch to be in a closed state. In the process of the first clutch transmitting torque in the slipping state, if the speed difference between the two ends of the first clutch is less than a certain difference, the first clutch will be closed.

[0089] In some embodiments, the HCU further sends a second clutch closing request to the TCU, so that the TCU maintains the second clutch closed based on the second clutch closing request. Figure 1 The K2 clutch shown.

[0090] like Figure 3 As shown, in stage 2, the state request of the K1 clutch changes to a closing request, and the state request of the K2 clutch remains a closing request; the actual state of the K1 clutch remains in an open state. The actual state of the K2 clutch remains in a closed state. In stage 3, the actual state of the K1 clutch changes to a slipping state, and in the first half of stage 3, the actual state of the K2 clutch remains in a closed state.

[0091] S14, when the first clutch is in a slipping state, controlling the engine output torque of the vehicle so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state, and when the first clutch is in a slipping state, controlling the second clutch to open.

[0092] Specifically, after receiving the signal from the TCU indicating that the first clutch is in the slipping state, the HCU determines that the first clutch is in the slipping state. After determining that the first clutch is in the slipping state, the HCU starts to control the engine to output torque.

[0093] like Figure 1 As shown, the torque output by the engine is transmitted to the odd-numbered shafts of the hybrid transmission through the first clutch K1 in a slipping state, and the odd-numbered shafts are transmitted to the front wheels of the vehicle through the currently engaged gear 1st gear.

[0094] like Figure 3 As shown, after the actual state of the K1 clutch changes to the slipping state in stage three, the engine torque gradually increases, the actual K1 clutch torque gradually increases, the engine speed gradually decreases, the speed of the hybrid transmission input shaft (odd-numbered shaft) gradually increases, and the engine begins to output torque through the K1 clutch in the slipping state.

[0095] like Figure 1 As shown, the vehicle also includes a K2 clutch 1032, i.e., a second clutch, which is used to control the connection and disconnection of the engine 104 and the second input shaft 1034 of the hybrid transmission 103. The second input shaft 1034 is connected to the first motor 101 (i.e., the front drive motor), so the second clutch also controls the connection and disconnection of the connection between the engine 104 and the first motor 101. In the series mode, the second clutch is closed, and the engine drives the front drive motor to reverse and generate electricity through the second clutch. After determining that the first clutch is in a slip state, the second clutch can also be controlled to open to disconnect the power output of the engine to the front drive motor.

[0096] It is understandable that the current target operating condition of the vehicle is a low-speed high-throttle scenario, indicating that the vehicle currently requires a larger power torque to drive the vehicle, and when the second clutch is in a closed state, the engine also needs to transmit part of the torque to the front drive motor for power generation. At this time, in order to meet the power torque required for vehicle driving, the second clutch needs to be opened.

[0097] In the above method, the target working condition is a working condition where the accelerator pedal depth is greater than a preset depth, i.e., a high throttle working condition. When it is determined that the vehicle needs to switch from the series mode to the direct drive mode under the high throttle working condition, after detecting that the odd-numbered shaft of the vehicle is in gear, the vehicle directly controls the first clutch to be in a slipping state, and controls the engine to output torque when the first clutch is in a slipping state, which can effectively reduce the delay in the power output of the vehicle during the mode switching process. In this embodiment, when switching from the series mode to the direct drive mode under the high throttle working condition, the clutch is controlled to start outputting power when it is in a slipping state. Compared with the prior art in which the clutch is controlled to be closed before power output, the control of the first clutch slipping does not require the speed difference between the two ends of the clutch to be less than a certain value, so the clutch can be controlled to be in a slipping state after determining that the odd-numbered shaft is in gear, and then the engine is controlled to output power, which shortens the time of engine power output during the mode switching process and can effectively reduce the delay in the power output of the vehicle.

[0098] In one possible implementation, when the first clutch is in a slipping state, the engine output torque of the vehicle is controlled so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state, including: when it is determined that the first clutch is in a slipping state, setting the actual operating mode of the vehicle to a direct drive mode; when the actual operating mode of the vehicle is set to the direct drive mode, controlling the engine output torque of the vehicle and controlling the clutch pressure of the first clutch to increase as the engine output torque increases, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state.

[0099] Specifically, after the HCU determines that the first clutch is in a slipping state, the vehicle can output the engine torque to the front wheels through the first clutch in a slipping state. There is a signal in the vehicle indicating the current operating mode of the vehicle. At this time, the signal can be set to direct drive mode, indicating that the actual operating mode of the vehicle is direct drive mode.

[0100] After determining that the first clutch is in a slipping state, the HCU also starts to increase the engine torque demand to instruct the engine to start outputting torque. The engine torque demand indicates that the front axle of the vehicle needs torque to drive the front wheels of the vehicle.

[0101] It is understandable that when the first clutch is in the open state, the engine is idling and does not output torque. When the first clutch is closed and the engine needs to be instructed to output torque, the engine torque demand needs to be increased. After the TCU detects that the actual operation mode of the vehicle is set to the direct drive mode and the torque demand increased by the HCU, it controls the first clutch to maintain slip and transmit the engine torque to the front wheels of the vehicle.

[0102] The engine output torque usually increases gradually from zero to the front axle required torque based on a certain slope. The TCU can control the clutch pressure of the first clutch to increase as the engine output torque increases, so as to control the torque transmitted by the first clutch to increase as the engine output torque increases.

[0103] In one possible implementation, when the first clutch is in a slipping state, the second clutch of the vehicle is controlled to open so that the vehicle switches from series mode to direct drive mode, including: when it is determined that the first clutch is in a slipping state, controlling the absolute value of the torque of the front drive motor of the vehicle to decrease; when it is determined that the absolute value of the actual torque of the front drive motor is reduced to the target torque, controlling the second clutch to open so that the vehicle switches from series mode to direct drive mode.

[0104] It is understandable that in the series mode, the vehicle engine transmits torque through the closed second clutch, and the first motor 101 (i.e., the front drive motor) is driven to reverse and generate electricity. At this time, the front drive motor has negative torque for generating electricity. Therefore, the absolute value of the torque of the front drive motor needs to be reduced before controlling the second clutch to open.

[0105] The target torque is the torque of the front motor when the second clutch can be safely opened, which is usually 0 Nm (Newton meter). Therefore, the second clutch can be controlled to open after the absolute value of the torque of the front motor is reduced to 0 Nm. Specifically, when the actual torque of the first motor 101 is 0 Nm, the HCU sends a second clutch opening request to the TCU; after receiving the K2 clutch opening request, the TCU controls the second clutch to open.

[0106] like Figure 3As shown, the first clutch is in a slipping state in stage 3, and in the first half of stage 3, the torque of the first motor 101 gradually changes from negative torque to 0 Nm. After the torque of the first motor 101 gradually changes from negative torque to 0 Nm, the state request of the K2 clutch changes to an opening request, and the actual state of the K2 clutch changes to an opening state.

[0107] In some embodiments, in direct drive mode, when the vehicle outputs torque based on the K1 clutch in a slipping state, the difference between the hybrid transmission input shaft speed and the engine speed becomes smaller and smaller. When the difference is less than a certain difference, the first clutch switches from the slipping state to the closed state.

[0108] like Figure 3 As shown, in stage 4, i.e., in direct drive mode, the engine speed and the hybrid transmission input shaft speed are maintained at the target speed of 1st gear, the engine torque and the actual K1 clutch torque are maintained the same as the front axle required torque, the first motor 101 is maintained at 0Nm state (i.e., shutdown state), and the K1 clutch is switched from the slip state to the closed state. The state request of the K2 clutch remains the open request and the actual state remains the open state, and the state request of the K1 clutch remains the closed state and the actual state remains the closed state. The first synchronizer 1035 remains in the gear-in completion state, and the second synchronizer 1036 remains in the gear-out completion state. The target gear position request of the odd-numbered shaft remains in 1st gear, the target gear position request of the even-numbered shaft remains in neutral, the actual target gear position request remains in 1st gear, and the target operation mode request remains in direct drive mode.

[0109] In the above method, when the vehicle switches from the series mode to the direct drive mode, the torque output by the engine has been controlled to be transmitted to the front wheels of the vehicle through the first clutch when the first clutch is in a slip state. At this time, opening the second clutch can prevent the engine from outputting torque to the front drive motor through the second clutch to generate electricity, thereby ensuring the driving power of the vehicle. And when the absolute value of the actual torque of the front drive motor is reduced to the target torque, the second clutch is controlled to open, thereby ensuring the safety of the front drive motor and avoiding the problem of the front drive motor spinning rapidly after the second clutch is opened when the actual torque of the front drive motor is not reduced.

[0110] In step 202, after the second input shaft is controlled to shift into the 2nd gear or the 4th gear, the actual gear position of the second input shaft may be monitored. When it is detected that the actual gear position of the second input shaft is still neutral, it is determined that the even gear (i.e., the 2nd gear or the 4th gear) on the second input shaft is unavailable.

[0111] It can be understood that when the vehicle switches from series mode to direct drive mode under the target operating condition of high throttle, the second input shaft needs to be shifted into gear in advance after the second clutch is controlled to open. The target gear position of the second input shaft can be determined based on the current odd-numbered shaft gear position. For example, the target gear position of the second input shaft is equal to the odd-numbered shaft gear position plus 1.

[0112] For example, if the current odd-numbered shaft gear is 1st gear, the target gear for the second input shaft to be engaged is 2nd gear, and if the current odd-numbered shaft gear is 3rd gear, the target gear for the second input shaft to be engaged is 4th gear.

[0113] As in the above embodiment, under the target working condition of low speed and high throttle, when switching modes, the odd-numbered shaft is controlled to be engaged in the 1st gear, that is, the current gear position of the odd-numbered shaft is the 1st gear, and it can be determined that the target gear position of the second input shaft is the 2nd gear, so after the second clutch is opened, the second input shaft is controlled to be engaged in the 2nd gear. If the actual gear position of the second input shaft is monitored to be neutral after the second input shaft is controlled to be engaged in the 2nd gear, it can be determined that the 2nd gear of the second input shaft is unavailable, and the vehicle mode switching state is stuck, and the state in which the vehicle is stuck can be called an intermediate state.

[0114] In step 203, when it is determined that the even gear of the second input shaft is unavailable, it can be determined that the vehicle is currently in an intermediate state and the vehicle mode change is stuck. At this time, the power output of the vehicle is limited and the vehicle cannot currently drive normally in direct drive mode. At this time, the vehicle needs to be switched to other modes to ensure that the vehicle power is not limited.

[0115] It is understandable that when the vehicle is driving in direct drive mode, it needs to gradually switch gears from 1st gear to 4th gear as the vehicle speed changes, where the corresponding vehicle speed from 1st gear to 4th gear is getting faster and faster. The even gears of the second input shaft are not available, that is, the vehicle cannot currently shift to 2nd gear or 4th gear. At this time, it is determined that the vehicle cannot drive normally in direct drive mode.

[0116] In the series mode, the engine does not need to output power to the front wheels of the vehicle, and the rear wheels of the vehicle are driven by the rear-drive motor. At this time, the vehicle does not need to be in gear, and the power output of the vehicle is not limited. Therefore, when it is determined that the even gear of the second input shaft is unavailable, it can be determined whether the vehicle currently meets the preset conditions for switching to the series mode. When it is confirmed that the vehicle meets the preset conditions for switching to the series mode, the vehicle is switched back to the series mode from the intermediate state.

[0117] The preset conditions include that the remaining power of the power battery is less than a preset power (eg, 20%) and / or the vehicle's required torque is less than a preset torque.

[0118] In the intermediate state, the second clutch is in an open state, and the second input shaft is in neutral gear; in the series mode, the second clutch is in a closed state, and the second input shaft is in neutral gear. When it is determined that the even gear on the second input shaft is unavailable, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, the second clutch can be controlled to close.

[0119] In one possible implementation, if it is monitored that the vehicle meets the preset conditions for switching to the series mode, the second clutch is controlled to close, including: if it is monitored that the vehicle meets the preset conditions for switching to the series mode, the front drive motor of the vehicle is controlled to rotate based on the target speed; the difference between the actual speed of the front drive motor and the target speed is calculated; when the difference is less than the preset difference, the second clutch is controlled to close.

[0120] It can be understood that controlling the closing of the second clutch requires that the speed difference between the two ends of the second clutch is less than a certain value to ensure safe closing of the clutch.

[0121] like Figure 1 The two ends of the K2 clutch 1032 (second clutch) shown are the first motor 101 (front drive motor) and the engine 104, respectively. When the vehicle switches from the series mode to the direct drive mode, the second clutch is opened after the absolute value of the torque of the front drive motor is controlled to drop to 0Nm, that is, the front drive motor is in a shutdown state in the intermediate state, and the speed of the front drive motor is 0 or close to 0. In the intermediate state, the engine is in a driving state, that is, the engine has a large speed. Therefore, when it is determined that the even gear on the second input shaft is unavailable, it is necessary to first control the front drive motor of the vehicle to rotate based on the target speed so that the speed difference at both ends of the second clutch is less than a certain value, so as to facilitate the subsequent closing of the second clutch.

[0122] The target speed may be determined based on the current speed of the engine. Specifically, the speed of the front drive motor when the speeds of the gears on both sides of the second clutch are the same may be determined based on the current speed of the engine to obtain the target speed.

[0123] During the rotation of the front-drive motor, the actual speed of the front-drive motor is monitored in real time, and when the difference between the actual speed of the front-drive motor and the target speed is less than a preset difference, the second clutch is controlled to close. The difference between the actual speed of the front-drive motor and the target speed is less than the preset difference, indicating that the speed difference between the two ends of the second clutch is small, and the clutch can be safely closed at this time.

[0124] Specifically, the various signals when switching from the series mode to the direct drive mode are recorded as the first signal. When it is determined that the even gear on the second input shaft is unavailable, the HCU in the vehicle sends the second odd-axis target gear signal, the second even-axis target gear signal, the second target operation mode signal, the second actual operation mode signal and the shift permission signal to the TCU, and sends the shift permission signal to the FMCU. Among them, the target gear carried by the second odd-axis target gear signal is the 1st gear or the 3rd gear, the target gear carried by the second even-axis target gear signal is the neutral gear, the target operation mode carried by the second target operation mode signal is the series mode, and the actual operation mode carried by the second actual operation mode signal is the direct drive mode.

[0125] When TCU receives the second target operation mode signal, the second actual operation mode signal, the second even-axis target gear signal, the second odd-axis target gear signal and the gear shift permission signal sent by HCU, it determines that the vehicle is currently in the intermediate state, and TCU sends a P2.5 motor speed control activation command to FMCU, calculates the target speed of the front P2.5 motor according to the current speed of the engine, and sends the target speed to FMCU.

[0126] When the FMCU receives the P2.5 motor speed activation command and the gear shift permission command, it controls the P2.5 motor to switch from torque control to speed control. When the P2.5 motor switches to speed control, the FMCU controls the P2.5 motor speed to follow the target speed calculated by the TCU.

[0127] Among them, in the torque control state, the front drive motor is controlled to rotate based on the target torque, and in the speed control state, the front drive motor is controlled to rotate based on the target speed.

[0128] When the front-drive motor of the vehicle is rotating, the actual speed of the front-drive motor is monitored in real time, the difference between the actual speed and the target speed is calculated, and when the difference is less than the preset difference (such as 100rpm), it is determined that the second clutch can be controlled to close. The HCU sends a second clutch closing command to the TCU. After receiving the second clutch closing command sent by the HCU, the TCU quickly closes the second clutch and sends the actual clutch closing status to the HCU.

[0129] In some embodiments, after receiving the second clutch closing command sent by the HCU, the TCU determines that the vehicle switches to the series mode. In the series mode, the P2.5 motor is controlled to generate electricity based on the generating torque. The TCU can also send a P2.5 motor speed control deactivation command to the FMCU. After the FMCU receives the P2.5 motor speed control deactivation command sent by the TCU, it controls the P2.5 motor to switch from speed control to torque control. When the P2.5 motor switches to torque control, the FMCU controls the P2.5 motor to generate electricity based on the generating torque.

[0130] In some embodiments, after the K2 clutch is closed, the vehicle switches to the series mode. In the series mode, the vehicle does not need to shift gears. The VCU can send a shift not allowed signal to the TCU / FMCU so that the TCU / FMCU no longer controls the vehicle shifting.

[0131] In step 204, in the intermediate state, the first clutch of the vehicle is closed, and the first input shaft is engaged in the first gear. In the series mode, the first clutch of the vehicle is opened, and the first input shaft is engaged in the first gear, the third gear, or the neutral gear. Therefore, after determining that the second clutch is closed, the first clutch needs to be opened to switch the vehicle back to the series mode from the current intermediate state.

[0132] In one possible implementation, when the second clutch is in a closed state, the first clutch is controlled to open, including: when the second clutch is in a closed state, the torque output by the vehicle's engine to the front wheels is reduced; when the torque output by the vehicle's engine to the front wheels is reduced to a preset torque, the first clutch is controlled to open to switch the vehicle from direct drive mode to series mode.

[0133] It can be understood that in the intermediate state, the first clutch is closed, and the engine outputs torque to the front wheels of the vehicle through the first clutch to drive the front wheels of the vehicle, that is, at this time, there is a certain torque on the front axle of the vehicle, that is, the engine of the vehicle outputs a certain torque to the front wheels of the vehicle. After the first clutch is opened, the engine no longer outputs torque to the front wheels of the vehicle to drive the vehicle, so before controlling the first clutch to open, it is necessary to reduce the torque output by the engine of the vehicle to the front wheels to a preset torque. Among them, the preset torque is usually 0NM.

[0134] In some embodiments, the torque output from the vehicle's engine to the front wheels is also referred to as the front axle torque. When the second clutch is in a closed state, after the front axle torque of the vehicle is reduced to equal to the preset torque 0 NM, the first clutch is controlled to open.

[0135] Specifically, when it is determined that the second clutch is closed and the P2.5 motor switches to torque control, the VCU controls the front axle torque to be reduced to 0Nm. When it is determined that the front axle torque is reduced to 0Nm, the HCU sends the first clutch opening command to the TCU. After receiving the first clutch opening command sent by the HCU, the TCU quickly opens the first clutch and sends the actual state of the first clutch as the open state to the HCU.

[0136] In some embodiments, after the first clutch is opened, the VCU may also set the actual operating mode of the vehicle to the series mode.

[0137] In one possible implementation, when the second clutch is in a closed state, the torque output from the vehicle's engine to the front wheels is controlled to be reduced, including: when the second clutch is in a closed state, the output torque of the engine is output as a power generation torque to the front drive motor of the vehicle, so that the torque output from the engine to the front wheels is reduced, and the front drive motor generates electricity based on the power generation torque.

[0138] like Figure 1 As shown, the front-drive motor is connected to the second clutch. After the second clutch is closed, the engine and the front-drive motor are connected. That is, after the second clutch is closed, the vehicle can transmit the torque output by the engine to the front-drive motor of the vehicle through the second clutch to generate electricity.

[0139] When the second clutch is in a closed state, the output torque of the engine can be used as the power generation torque, and the power generation torque can be transmitted to the front drive motor through the second clutch to reduce the torque output by the engine to the front wheels, that is, to reduce the torque of the front axle of the vehicle.

[0140] The front-drive motor can generate electricity based on the transmitted generating torque, and transmit the generated electric energy to the high-voltage battery to charge the high-voltage battery.

[0141] In some embodiments, when the second clutch is in a closed state, reducing the torque output by the engine to the front wheels also includes: controlling the engine to maintain idle rotation, reducing the torque output by the engine, and reducing the front axle torque of the vehicle to 0Nm.

[0142] It is understandable that in direct drive mode, the vehicle engine drives the front wheels of the vehicle while the rear drive motor drives the rear wheels of the vehicle, and the vehicle has front axle demand torque and rear axle demand torque. In series mode, the vehicle is driven by the rear drive motor. When switching from the intermediate state to the series mode, the front axle demand torque of the vehicle needs to be transferred to the rear axle demand torque to ensure normal driving of the vehicle.

[0143] In summary, in the present application, when the vehicle is stuck during the process of switching from the series mode to the direct drive mode, the vehicle is directly controlled to switch back to the series mode, which ensures the normal output of the vehicle power and avoids the problem that the vehicle is stuck in the middle state, resulting in the problem of limited system output power. And directly switching back to the series mode before the vehicle switches modes is simple and efficient, ensuring the normal driving of the vehicle. And when it is determined that the vehicle is in a scenario where the series mode switches to the direct drive mode under a large throttle condition, it can be determined that the speed difference between the two ends of the first clutch is large. At this time, when the first clutch is controlled to be in a slip state, the engine output power is controlled. Compared with the method of controlling the clutch to close and then controlling the engine output torque in the prior art, the engine power output time during the mode switching process is shortened, which can effectively reduce the delay in the vehicle power output. When the first clutch is in a slip state, opening the second clutch can avoid the engine outputting torque to the front drive motor through the second clutch to generate electricity, thereby ensuring the power of the vehicle. And when the absolute value of the actual torque of the front-drive motor is reduced to the target torque, the second clutch is controlled to open, which ensures the safety of the front-drive motor and avoids the problem of the front-drive motor spinning after the second clutch is opened when the actual torque of the front-drive motor is not reduced.

[0144] Figure 4 1 is a schematic diagram of a control mode switching device provided in an embodiment of the present application. The device 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.

[0145] For example, Figure 4 As shown, the device 400 includes:

[0146] The first control module 401 is used for controlling the second input shaft to engage an even-numbered gear when it is determined that the second clutch is open during the process of the vehicle switching from the series mode to the direct drive mode;

[0147] A determination module 402 is used to determine that the even-numbered gear on the second input shaft is unavailable if it is detected that the gear position of the second input shaft is neutral;

[0148] The second control module 403 is used for controlling the second clutch to close if it is detected that the vehicle meets the preset condition for switching to the series mode when it is determined that the even gear on the second input shaft is unavailable;

[0149] The third control module 404 is configured to control the first clutch to open when the second clutch is in a closed state, so as to switch the vehicle from the direct drive mode back to the series drive mode.

[0150] In one possible implementation, the second control module 403 is specifically used to control the front drive motor of the vehicle to rotate based on the target speed if it is monitored that the vehicle meets the preset conditions for switching to the series mode; calculate the difference between the actual speed of the front drive motor and the target speed; and control the second clutch to close when the difference is less than the preset difference.

[0151] In one possible implementation, the third control module 404 is specifically used to control the torque output from the vehicle's engine to the front wheels to be reduced when the second clutch is in a closed state; and to control the first clutch to be opened when the torque output from the vehicle's engine to the front wheels is reduced to a preset torque.

[0152] In one possible implementation, the third control module 404 is specifically used to output the output torque of the engine as a generating torque to the front drive motor of the vehicle when the second clutch is in a closed state, so as to reduce the torque output by the engine to the front wheels and enable the front drive motor to generate electricity based on the generating torque.

[0153] In one possible implementation, the device also includes: a judgment module, which is used to judge whether the vehicle is in a target operating condition when it is determined that the vehicle needs to switch from a series mode to a direct drive mode; wherein the target operating condition is a condition in which the depth of the vehicle's accelerator pedal is greater than a preset depth; a detection module, which is used to detect whether the first input shaft of the vehicle is engaged in an odd gear when it is determined that the vehicle is in the target operating condition; a fourth control module, which is used to control the first clutch to be in a slipping state when the first input shaft is engaged in an odd gear; and a fifth control module, which is used to control the engine output torque of the vehicle when the first clutch is in a slipping state, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state, and controls the second clutch to open when the first clutch is in a slipping state.

[0154] In one possible implementation, the fifth control module is specifically used to, when it is determined that the first clutch is in a slipping state, set the actual operating mode of the vehicle to the direct drive mode; when the actual operating mode of the vehicle is set to the direct drive mode, control the engine output torque of the vehicle, and control the clutch pressure of the first clutch to increase as the engine output torque increases, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slipping state.

[0155] In one possible implementation, the fifth control module is specifically used to control the absolute value of the torque of the vehicle's front drive motor to decrease when it is determined that the first clutch is in a slipping state; and to control the second clutch to open when it is determined that the absolute value of the actual torque of the front drive motor is reduced to the target torque.

[0156] Figure 5 It is a structural schematic diagram of a vehicle provided in an embodiment of the present application.

[0157] 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 switching a control mode.

[0158] In addition, an embodiment of the present application also protects a device, which may include a memory and a processor, wherein the memory stores an executable program code, and the processor is used to call and execute the executable program code to perform a method for control mode switching provided in an embodiment of the present application.

[0159] In this embodiment, the functional modules of the device can be divided according to the above method example. For example, each functional module can be corresponded, or two or more functions can be integrated into one processing module. The above integrated module can be implemented in the form of hardware. It should be noted that the division of modules in this embodiment is schematic and is only a logical function division. There may be other division methods in actual implementation.

[0160] In the case of dividing each functional module according to each function, the device may also include a first control module, a determination module, a second control module, and a third control module. 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, which will not be repeated here.

[0161] It should be understood that the device provided in this embodiment is used to execute the above-mentioned method for switching control modes, and thus can achieve the same effect as the above-mentioned implementation method.

[0162] In the case of an integrated unit, the device may include a processing module and a storage module. When the device is applied to a vehicle, the processing module may be used to control and manage the actions of the vehicle. The storage module may be used to support the vehicle in executing relevant program codes, etc.

[0163] The processing module may be a processor or a controller, which may implement or execute various exemplary logic blocks, modules and circuits shown in combination with the contents disclosed in this application. The processor may also be a combination that implements computing functions, such as a combination of one or more microprocessors, a combination of digital signal processing (DSP) and a microprocessor, etc. The storage module may be a memory.

[0164] In addition, the device provided in the embodiments of the present application may specifically be a chip, a component or a module, and the chip may include a connected processor and a memory; wherein the memory is used to store instructions, and when the processor calls and executes the instructions, the chip can execute a control mode switching method provided in the above embodiments.

[0165] This embodiment also provides a computer-readable storage medium, in which a computer program code is stored. When the computer program code is executed on a computer, the computer executes the above-mentioned related method steps to implement a control mode switching method provided in the above embodiment.

[0166] 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 control mode switching method provided in the above embodiment.

[0167] Among them, the device, computer-readable storage medium, computer program product or chip provided in this embodiment is used to execute the corresponding method provided above. Therefore, the beneficial effects that can be achieved can refer to the beneficial effects in the corresponding method provided above, and will not be repeated here.

[0168] 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 assigned to 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.

[0169] In the embodiments provided in the present 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 only schematic, for example, the division of modules or units is only a logical function division, and there may be other division methods in actual implementation, 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.

[0170] The above contents are only specific implementation methods of the present application, but the protection scope of the present application is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed in the present application, which should be included in the protection scope of the present application. Therefore, the protection scope of the present application should be based on the protection scope of the claims.

Claims

1. A method for switching a control mode, characterized in that: A hybrid vehicle is applied, the vehicle includes a hybrid transmission, the hybrid transmission includes: a first input shaft and a second input shaft, the first input shaft is connected to a first clutch, the second input shaft is connected to a second clutch, the method includes: When the vehicle is switched from the series mode to the direct drive mode, if it is determined that the second clutch is open, controlling the second input shaft to engage an even-numbered gear; If it is detected that the gear position of the second input shaft is neutral, determining that the even-numbered gear on the second input shaft is unavailable; In the case where it is determined that the even-numbered gear on the second input shaft is unavailable, if it is monitored that the vehicle meets a preset condition for switching to the series mode, controlling the second clutch to close; When the second clutch is in the closed state, the first clutch is controlled to be opened, so that the vehicle switches back from the direct drive mode to the series mode.

2. The method according to claim 1, characterized in that If it is detected that the vehicle meets the preset condition for switching to the series mode, controlling the second clutch to close includes: If it is detected that the vehicle meets a preset condition for switching to the series mode, controlling the front drive motor of the vehicle to rotate based on a target speed; Calculating a difference between an actual rotation speed of the front drive motor and the target rotation speed; When the difference is smaller than a preset difference, the second clutch is controlled to close.

3. The method according to claim 1, characterized in that When the second clutch is in a closed state, controlling the first clutch to open includes: When the second clutch is in a closed state, controlling the torque outputted from the engine of the vehicle to the front wheels to be reduced; When the torque output from the engine of the vehicle to the front wheels is reduced to a preset torque, the first clutch is controlled to be opened.

4. The method according to claim 3, characterized in that When the second clutch is in a closed state, controlling the torque outputted from the engine of the vehicle to the front wheels to be reduced comprises: When the second clutch is in a closed state, the output torque of the engine is output as power generation torque to the front drive motor of the vehicle, so that the torque output by the engine to the front wheels is reduced and the front drive motor generates electricity based on the power generation torque.

5. The method according to any one of claims 1 to 4, characterized in that: When it is determined that the second clutch is open, before controlling the second input shaft to engage in an even-numbered gear, the method further includes: In the case where it is determined that the vehicle needs to switch from the series mode to the direct drive mode, determining whether the vehicle is in a target operating condition; wherein the target operating condition is a condition in which the accelerator pedal depth of the vehicle is greater than a preset depth; In the case where it is determined that the vehicle is in the target operating condition, detecting whether the first input shaft of the vehicle is engaged in an odd-numbered gear; When the first input shaft is engaged in an odd-numbered gear, controlling the first clutch to be in a slipping state; When the first clutch is in a slipping state, the engine output torque of the vehicle is controlled so that the first clutch transmits the torque output by the engine to the wheels of the vehicle in the slipping state, and when the first clutch is in a slipping state, the second clutch is controlled to open.

6. The method according to claim 5, characterized in that When the first clutch is in a slipping state, controlling the engine output torque of the vehicle so that the first clutch transmits the torque output by the engine to the wheels of the vehicle in the slipping state includes: When it is determined that the first clutch is in a slipping state, setting the actual operation mode of the vehicle to a direct drive mode; When the actual operating mode of the vehicle is set to the direct drive mode, the engine output torque of the vehicle is controlled, and the clutch pressure of the first clutch is controlled to increase as the engine output torque increases, so that the first clutch transmits the engine output torque to the wheels of the vehicle in the slip state.

7. The method according to claim 5, characterized in that When the first clutch is in a slipping state, controlling the second clutch of the vehicle to open includes: When it is determined that the first clutch is in a slipping state, controlling the absolute value of the torque of the front drive motor of the vehicle to decrease; When it is determined that the absolute value of the actual torque of the front drive motor is reduced to the target torque, the second clutch is controlled to be opened.

8. A device for controlling mode switching, characterized in that: A hybrid vehicle is applied, the vehicle includes a hybrid transmission, the hybrid transmission includes: a first input shaft and a second input shaft, the first input shaft is connected to a first clutch, the second input shaft is connected to a second clutch, the device includes: The first control module is used for controlling the second input shaft to engage an even-numbered gear when it is determined that the second clutch is open during the process of the vehicle switching from the series mode to the direct drive mode; a determination module, configured to determine that an even-numbered gear on the second input shaft is unavailable if it is detected that the gear position of the second input shaft is a neutral gear; a second control module, configured to control the second clutch to close if it is detected that the vehicle meets a preset condition for switching to the series mode when it is determined that the even-numbered gear on the second input shaft is unavailable; The third control module is used for controlling the first clutch to open when the second clutch is in a closed state, so that the vehicle switches from the direct drive mode back to the series drive mode.

9. A vehicle, characterized in that: The vehicle comprises: A memory for storing executable program codes; A processor, 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 7.

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 7 is implemented.

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