Pure electric vehicle drivetrain control methods and pure electric vehicles

Abstract

This invention discloses a pure electric vehicle drivetrain control method and a pure electric vehicle. The pure electric vehicle drivetrain control method includes: when the accelerator pedal is released in driving mode or the brake pedal is released in regenerative braking mode, determining whether the vehicle enters a delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed; if the vehicle enters the delay mode, a timer is started for a duration; simultaneously, the required preload torque is determined based on the current vehicle speed; the motor outputs the required preload torque; and the vehicle exits the delay mode based on the timer duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed. This method offers high control precision, effectively reducing abnormal noises caused by sudden torque changes, improving driving comfort, and enhancing safety.

Description

Technical Field

[0001] This invention relates to the field of vehicle technology, and more particularly to a control method for the powertrain of a pure electric vehicle and a pure electric vehicle. Background Technology

[0002] The traditional gasoline-powered vehicle industry faces enormous challenges due to energy shortages and climate change, making energy-efficient and environmentally friendly electric vehicles increasingly important. Unlike traditional gasoline-powered vehicles, pure electric vehicles generate negative torque through energy recovery. Therefore, during operation, pure electric vehicles frequently alternate between braking and driving states, inevitably causing frequent abrupt changes in the motor's output torque. In particular, the transmission system of pure electric vehicles, especially the transmission mechanism between the motor and wheels, has gaps between gear meshing and keyed connections. Sudden acceleration or braking, causing abrupt changes in the motor's output torque, can lead to collisions between gears and keyed connections, resulting in abnormal noises.

[0003] To address this phenomenon, existing pure electric vehicle drive system control methods can reduce abnormal noise by controlling changes in the output torque of the motor. However, the control effect and accuracy of existing pure electric vehicle drive system control methods are poor. Summary of the Invention

[0004] The purpose of this invention is to provide a pure electric vehicle drivetrain control method and a pure electric vehicle, so as to solve the problems of poor control effect and poor control accuracy in the existing pure electric vehicle drivetrain control methods.

[0005] To achieve this objective, the present invention adopts the following technical solution:

[0006] The control method for the powertrain of a pure electric vehicle includes:

[0007] When the accelerator pedal is released in drive mode or the brake pedal is released in regenerative braking mode, the system determines whether the vehicle enters a delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed.

[0008] If the vehicle enters the delay mode, a timer begins and lasts for a specified duration. Simultaneously, the required preload torque is determined based on the vehicle's current speed, and the motor outputs the required preload torque.

[0009] The vehicle is determined to exit the delay mode based on the timeout duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed.

[0010] As a preferred embodiment of the above-mentioned pure electric vehicle transmission system control method, the delay mode includes a first delay mode, the timing duration includes a first timing duration, and the required preload torque includes a first required preload torque. When the vehicle releases the accelerator pedal in drive mode, the specific steps for determining whether the vehicle has entered the delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed include:

[0011] Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed; determine if the vehicle is currently in neutral.

[0012] If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then determine whether the current vehicle speed is within the first set speed range; and whether the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change.

[0013] If the current vehicle speed is within the first set vehicle speed range, and the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change, then the vehicle enters the first delay mode.

[0014] If the vehicle enters the first delay mode, the timing begins for the first timing duration; at the same time, the first required preload torque of the vehicle is determined based on the current vehicle speed; the motor outputs the first required preload torque.

[0015] As a preferred embodiment of the above-mentioned pure electric vehicle transmission system control method, when the vehicle enters the first delay mode, the specific steps for determining whether the vehicle exits the delay mode based on the timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed include:

[0016] Real-time detection of whether the brake pedal is pressed; real-time detection of whether the accelerator pedal is pressed; determination of whether the first timing duration is greater than the first set duration;

[0017] If the brake pedal is pressed, or the accelerator pedal is pressed, or the first timer duration exceeds the first set duration, then exit the first delay mode.

[0018] As a preferred embodiment of the above-mentioned pure electric vehicle powertrain control method, after exiting the first delay mode, the pure electric vehicle powertrain control method further includes:

[0019] Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed.

[0020] If neither the brake pedal nor the accelerator pedal is pressed, the vehicle's driving mode is determined based on the current speed.

[0021] As a preferred embodiment of the above-mentioned pure electric vehicle drivetrain control method, determining the vehicle's driving mode based on the current vehicle speed includes:

[0022] Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery;

[0023] If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle enters the coasting recovery mode;

[0024] If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0025] As a preferred embodiment of the above-mentioned pure electric vehicle drivetrain control method, when the vehicle enters the coasting recovery mode, the following steps are also included:

[0026] Real-time detection of whether the brake pedal is pressed;

[0027] If you press the brake pedal, the vehicle will enter regenerative braking mode;

[0028] Real-time detection of whether the accelerator pedal is pressed;

[0029] If the accelerator pedal is pressed, the vehicle enters the aforementioned driving mode;

[0030] Real-time detection of whether the vehicle is in neutral;

[0031] If the vehicle's current gear is returned to neutral, the vehicle will be controlled to enter the initial mode;

[0032] Real-time detection of whether the vehicle speed is greater than or equal to the set speed for coasting recovery;

[0033] If the vehicle speed is greater than or equal to the set speed for coasting recovery, the vehicle maintains the coasting recovery mode;

[0034] If the vehicle speed is less than the set speed for coasting recovery, the vehicle enters the crawl mode.

[0035] As a preferred embodiment of the above-mentioned pure electric vehicle transmission system control method, the delay mode further includes a second delay mode, the timing duration further includes a second timing duration, and the required preload torque further includes a second required preload torque. When the vehicle releases the brake pedal in regenerative braking mode, the specific steps for determining whether the vehicle has entered the delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed include:

[0036] Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed; determine if the vehicle is currently in neutral.

[0037] If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then determine whether the current vehicle speed is within the second set speed range; and whether the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate.

[0038] If the current vehicle speed is within the second set vehicle speed range, and the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate, then the vehicle enters the second delay mode.

[0039] If the vehicle enters the second delay mode, the timing begins for the second timing duration; at the same time, the second required preload torque of the vehicle is determined based on the current vehicle speed; the motor outputs the second required preload torque.

[0040] As a preferred embodiment of the above-mentioned pure electric vehicle transmission system control method, when the vehicle enters the second delay mode, the specific steps for determining whether the vehicle exits the delay mode based on the timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed include:

[0041] Real-time detection of whether the brake pedal is pressed; real-time detection of whether the accelerator pedal is pressed; determination of whether the second timing duration is greater than the second set duration;

[0042] If the brake pedal is pressed, or the accelerator pedal is pressed, or the second timer duration exceeds the second set duration, then exit the second delay mode.

[0043] As a preferred embodiment of the above-mentioned pure electric vehicle powertrain control method, the pure electric vehicle powertrain control method further includes:

[0044] Once the vehicle enters the initial mode, it determines whether to enter drive mode based on the vehicle's current gear position and whether the accelerator pedal is pressed.

[0045] As a preferred embodiment of the above-mentioned pure electric vehicle drivetrain control method, the specific steps for determining whether the vehicle enters drive mode based on the vehicle's current gear status and whether the accelerator pedal is pressed include:

[0046] Determine the vehicle's current gear;

[0047] If the vehicle's current gear is not neutral or park, determine whether the accelerator pedal is pressed.

[0048] If you press the accelerator pedal, the vehicle will enter drive mode.

[0049] As a preferred embodiment of the above-mentioned pure electric vehicle powertrain control method, the pure electric vehicle powertrain control method further includes:

[0050] If the accelerator pedal is pressed before the brake pedal is fully released, the vehicle will be put into regenerative braking mode.

[0051] A pure electric vehicle includes a pure electric vehicle drivetrain, which includes a motor, a transmission mechanism, and wheels. The input end of the transmission mechanism is connected to the output shaft of the motor, and the output end of the transmission mechanism is connected to the wheels. It is used to implement the above-described pure electric vehicle drivetrain control method.

[0052] The beneficial effects of this invention are:

[0053] The purpose of this invention is to provide a pure electric vehicle drivetrain control method and a pure electric vehicle. The pure electric vehicle drivetrain control method includes: when the accelerator pedal is released in driving mode or the brake pedal is released in regenerative braking mode, determining whether the vehicle should enter a delay mode based on whether the brake pedal is depressed and the rate of change in brake pedal depth, whether the accelerator pedal is depressed and the rate of change in accelerator pedal depth, the current gear position, and the current vehicle speed. This setting ensures that the vehicle only enters a delay mode to adjust the motor's output torque when a sudden torque change causes a significant abnormal noise. Compared to the prior art where the motor's output torque is directly controlled to approach zero when a sudden torque change occurs, this effectively improves the accuracy and precision of the vehicle entering the delay mode and also reduces the energy consumption of the pure electric vehicle. Specifically, if the vehicle... When a vehicle enters the delay mode, a timer begins, which is set for a specified duration. Simultaneously, the required preload torque is determined based on the vehicle's current speed, and the motor outputs the required preload torque. In other words, within the delay mode, the optimal required preload torque value changes with the vehicle's current speed, allowing for real-time matching of the optimal preload torque. Controlling the vehicle based on this optimal preload torque further reduces abnormal noises caused by sudden torque changes. Then, the timer duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed determine whether the vehicle exits the delay mode, further improving control precision and accuracy, and further reducing the energy consumption of pure electric vehicles.

[0054] Therefore, the pure electric vehicle transmission system control method can control pure electric vehicles with high control precision and accuracy, effectively improve the phenomenon of abnormal noise caused by sudden torque changes, reduce the energy consumption of pure electric vehicles, and effectively improve driving comfort and user experience. Attached Figure Description

[0055] Figure 1 This is a flowchart of a pure electric vehicle drive system control method provided in a specific embodiment of the present invention. Figure 1 ;

[0056] Figure 2 This is a flowchart of a pure electric vehicle drive system control method provided in a specific embodiment of the present invention. Figure 2 . Detailed Implementation

[0057] The present invention will now be described in further detail with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and not intended to limit it. Furthermore, it should be noted that, for ease of description, the accompanying drawings show only the parts relevant to the present invention, and not all of the structures.

[0058] In the description of this invention, unless otherwise explicitly specified and limited, the terms "connected," "linked," and "fixed" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention based on the specific circumstances.

[0059] In this invention, unless otherwise explicitly specified and limited, "above" or "below" the second feature can include direct contact between the first and second features, or contact between the first and second features through another feature between them. Furthermore, "above," "over," and "on top" of the second feature includes the first feature directly above or diagonally above the second feature, or simply indicates that the first feature is at a higher horizontal level than the second feature. "Below," "below," and "under" the second feature includes the first feature directly below or diagonally below the second feature, or simply indicates that the first feature is at a lower horizontal level than the second feature.

[0060] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on the present invention. In addition, the terms "first" and "second" are used only for distinction in description and have no special meaning.

[0061] This invention provides a pure electric vehicle, including a pure electric vehicle drivetrain. The pure electric vehicle drivetrain includes a motor, a transmission mechanism, and wheels. The input end of the transmission mechanism is connected to the output shaft of the motor, and the output end of the transmission mechanism is connected to the wheels. Thus, the motor can drive the wheels to rotate, enabling the vehicle to move.

[0062] Specifically, in this invention, pure electric vehicles mainly refer to pure electric buses or pure electric trucks, etc.

[0063] Pure electric vehicles typically have initial mode, drive mode, creep mode, regenerative braking mode, and coasting regenerative braking mode.

[0064] The initial mode refers to the state of a pure electric vehicle after low-voltage power is applied, provided the vehicle is fault-free, and before entering drive mode. It's important to clarify that for pure electric buses or trucks, starting the vehicle involves: turning the key from the "lock" position to the "ON" position, illuminating all instrument panel backlights, indicating low-voltage connection; then turning the key to the "Start" position, hearing a "beep" sound and two "clicks" of the relays closing within the battery pack, indicating high-voltage connection of the battery pack, and the "READY" green light on the instrument panel. At this point, the battery pack, motor, and other components have successfully received high-voltage power, and the high-voltage circuit between the motor and battery pack is normal, indicating normal motor operation. The vehicle can then transition from the initial mode to drive mode.

[0065] Driving mode refers to the mode of operation when the vehicle is in forward or reverse gear and the accelerator is pressed.

[0066] Crawl mode, also known as low-speed cycle driving assistance system, means that the driver does not need to press the brake pedal or the accelerator pedal to maintain a constant low speed.

[0067] Regenerative braking mode refers to the operating mode in which the vehicle recovers energy after the brake pedal is pressed.

[0068] Coasting recovery mode refers to the working mode in which energy is recovered when the vehicle is coasting.

[0069] Among them, electric motor is a general term for devices that convert electrical energy into mechanical energy. According to the reversible principle of electric motor, the same electric motor can operate as both a generator and an electric motor. Specifically, when an electric motor is used as a drive, it is equivalent to an electric motor, which can convert electrical energy into mechanical energy to drive a vehicle. When an electric motor is used as a generator, it is equivalent to a generator, which can convert mechanical energy into electrical energy to brake a vehicle.

[0070] For pure electric vehicles, due to the inherent gaps in the gear meshing and keyed connections within the drivetrain, especially the transmission mechanism between the motor and wheels, sudden acceleration or braking can cause abrupt changes in the motor's output torque. This can lead to collisions between the gears and keyed connections, resulting in abnormal noises. Existing drivetrain control methods for pure electric vehicles can mitigate these noises by controlling changes in the motor's output torque; however, these methods suffer from poor control effectiveness and precision.

[0071] Therefore, in response to this phenomenon, the present invention also provides a pure electric vehicle transmission system control method. Using this pure electric vehicle transmission system control method to control pure electric vehicles, the control precision and accuracy are high, which can effectively improve the phenomenon of abnormal noise caused by sudden torque changes in the vehicle, reduce the energy consumption of pure electric vehicles, and effectively improve driving comfort and enhance user experience.

[0072] Specifically, such as Figure 1 and Figure 2 As shown, the pure electric vehicle drive system control method specifically includes the following steps:

[0073] S100, Confirm that the vehicle has entered the initial mode.

[0074] Specifically, the steps to determine when a vehicle enters the initial mode include:

[0075] Determine if the pure electric vehicle is connected to low-voltage power; if so, determine if the vehicle has a malfunction; if not, the vehicle enters initial mode. At this point, the vehicle can be controlled to transition from initial mode to drive mode. Then execute S200.

[0076] Factors that determine whether a vehicle is faulty include, but are not limited to, whether the battery pack is faulty and whether the motor is faulty. Specifically, if the battery and / or motor is faulty, the fault will be reported on the instrument panel.

[0077] S200 determines whether the vehicle enters drive mode based on the vehicle's current gear position and whether the accelerator pedal is pressed.

[0078] Specifically, the steps to determine whether a vehicle has entered drive mode based on its current gear position and whether the accelerator pedal is pressed include:

[0079] Determine the vehicle's current gear.

[0080] If the vehicle's current gear is not neutral or park, then determine whether to press the accelerator pedal.

[0081] If the accelerator pedal is pressed, the vehicle enters drive mode. Execute S300.

[0082] If the vehicle's current gear is neutral or park (P), and / or the accelerator pedal is not depressed, the vehicle is not in drive mode. Specifically, if the vehicle's current gear is not neutral or park (P), i.e., it is in drive or reverse, and the accelerator pedal is not depressed, the vehicle enters crawl mode. It is understood that the brake pedal should not be depressed when the vehicle transitions from initial mode to drive mode or crawl mode.

[0083] Continue to determine the vehicle's current gear and whether the accelerator pedal is pressed; until the vehicle's current gear is not neutral or park, and the accelerator pedal is pressed, the vehicle enters drive mode.

[0084] Specifically, the delay modes include a first delay mode and a second delay mode. When the vehicle is in drive mode, releasing the accelerator pedal determines whether to enter the first delay mode; when the vehicle is in regenerative braking mode, releasing the brake pedal determines whether to enter the second delay mode. The timing duration includes a first timing duration and a second timing duration, with the first timing duration corresponding to the first delay mode and the second timing duration corresponding to the second delay mode. The required preload torque includes a first required preload torque and a second required preload torque, with the first required preload torque corresponding to the first delay mode and the second required preload torque corresponding to the second delay mode.

[0085] When the vehicle is in drive mode, pressing and releasing the accelerator pedal triggers S300.

[0086] S300 determines whether the vehicle enters the first delay mode based on whether the brake pedal is pressed and the rate of change of the brake pedal depth, whether the accelerator pedal is pressed and the rate of change of the accelerator pedal depth, the current gear status, and the current vehicle speed.

[0087] The brake pedal depth change rate refers to the amount of change in brake pedal depth per unit time.

[0088] Among them, the accelerator pedal depth change rate refers to the amount of change in accelerator pedal depth per unit time.

[0089] Specifically, the steps for determining whether a vehicle has entered the first delay mode based on whether the brake pedal is depressed and the rate of change of brake pedal depth, whether the accelerator pedal is depressed and the rate of change of accelerator pedal depth, the current gear position, and the current vehicle speed include:

[0090] Steps S310, S320, and S330 are preferably performed simultaneously.

[0091] S310, Determine whether the brake pedal is pressed.

[0092] If the brake pedal is pressed, the vehicle will enter regenerative braking mode.

[0093] S320: Determine whether the accelerator pedal is currently pressed.

[0094] If the accelerator pedal is pressed, the vehicle will remain in drive mode.

[0095] S330: Determine if the vehicle is currently in neutral.

[0096] If the vehicle's current gear is returned to neutral, the vehicle will be controlled to enter the initial mode. Specifically, when the vehicle's current gear is returned to neutral, it is determined that the driver intends to stop, and the vehicle will be controlled to enter the initial mode.

[0097] If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then proceed to step S340. At this time, the brake pedal depth change rate is zero.

[0098] S340, Determine whether the current vehicle speed is within the first set vehicle speed range; determine whether the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change.

[0099] If the current vehicle speed is within the first set speed range, and the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change, then the vehicle enters the first delay mode. Execute S400.

[0100] Specifically, for different types and sizes of pure electric vehicles, the speed range corresponding to a significant abnormal noise caused by a sudden torque change varies. For example, some pure electric vehicles experience significant abnormal noises due to sudden torque changes at low speeds, while others experience them at high speeds. Secondly, a large absolute value of the rate of change in accelerator pedal depth can also lead to significant abnormal noises caused by sudden torque changes. Therefore, by using the vehicle's current speed and the absolute value of the rate of change in accelerator pedal depth to determine whether the vehicle enters the first delay mode, the vehicle only enters the first delay mode to adjust the motor's output torque when a significant abnormal noise occurs due to a sudden torque change in drive mode. Compared to existing technologies that directly control the motor's output torque to near zero when a sudden torque change occurs, this effectively improves the accuracy and precision of the vehicle's transition from drive mode to the first delay mode.

[0101] The first set speed range is an empirical value obtained from a large number of previous tests. The first set speed range is different for different types of pure electric vehicles and pure electric vehicles of different sizes.

[0102] The first set rate of change is an empirical value obtained from a large number of previous experiments.

[0103] If the current vehicle speed is not within the first set speed range, and / or the absolute value of the rate of change of accelerator pedal depth is less than the first set rate of change, then the vehicle's driving mode is determined based on the current vehicle speed.

[0104] Understandably, if the current vehicle speed is not within the first set speed range, it means that in drive mode, the current speed is not enough to cause a large abnormal noise when the vehicle experiences a sudden change in torque. If the absolute value of the rate of change of accelerator pedal depth is less than the first set rate of change, it means that the driver did not press the accelerator pedal very hard. In this case, the sudden change in torque is relatively smooth and will not cause a large abnormal noise when the torque changes.

[0105] This setting can further improve the accuracy and precision of the vehicle entering the first delay mode, and also reduce the electrical energy consumed when adjusting torque sudden changes, thereby reducing the energy consumption of pure electric vehicles.

[0106] The specific steps for determining the vehicle's driving mode based on the current vehicle speed include:

[0107] Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery.

[0108] If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle will enter the coasting recovery mode.

[0109] If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0110] It is understandable that the coasting recovery set speed is the critical speed for entering the coasting recovery mode. When the current speed is less than the coasting recovery set speed, it indicates that the current speed is insufficient for energy recovery in coasting mode, so the vehicle enters crawl mode.

[0111] The speed set for coasting recovery is an empirical value obtained from a large number of previous tests.

[0112] S400, start timing for the first timing duration; at the same time, determine the vehicle's first required preload torque based on the vehicle's current speed; the motor outputs the first required preload torque.

[0113] Specifically, the controller of a pure electric vehicle controls the motor based on the first required preload torque, ensuring that the motor's output torque is equal to the first required preload torque. This first required preload torque is less than the maximum output torque of the motor at the previous moment, allowing for a smooth transition in the motor's output torque.

[0114] Specifically, assuming the vehicle transitions from driving mode to the first delay mode, a first cur is obtained from extensive prior testing, which correlates the vehicle speed with the first required preload torque. The first required preload torque is then determined from this first cur based on the vehicle's current speed.

[0115] Preferably, in the first delay mode, as the vehicle's current speed changes, the value of the optimal first required preload torque will also change accordingly, so that the optimal first required preload torque can be matched in real time according to the vehicle's current speed. At this time, controlling the vehicle to drive according to the optimal first required preload torque can better reduce the phenomenon of abnormal noise caused by sudden torque changes in the vehicle.

[0116] As an alternative, assuming the vehicle transitions from driving mode to the first delay mode, a first table of vehicle speed and required preload torque can be obtained from extensive prior testing. The required preload torque can then be retrieved from this first table based on the vehicle speed when entering the first delay mode.

[0117] S500 determines whether the vehicle has exited the first delay mode based on the first timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed.

[0118] Specifically, the steps for determining whether the vehicle has exited the first delay mode based on the first timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed include:

[0119] Steps S510, S520, and S530 are preferably performed simultaneously.

[0120] S510: Real-time detection of whether the brake pedal is pressed.

[0121] If you press the brake pedal, the vehicle will enter regenerative braking mode.

[0122] S520: Real-time detection of whether the accelerator pedal is pressed.

[0123] If you press the accelerator pedal, the vehicle will enter drive mode.

[0124] S530, Determine whether the first timing duration is greater than the first set duration.

[0125] If the first timeout duration exceeds the first set duration, exit the first delay mode.

[0126] After exiting the first delay mode, determine whether the brake pedal is pressed; determine whether the accelerator pedal is pressed.

[0127] If neither the brake pedal nor the accelerator pedal is pressed, the vehicle's driving mode is determined based on the current speed.

[0128] Specifically, the steps for determining the vehicle's driving mode based on the current vehicle speed include:

[0129] Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery.

[0130] If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle will enter the coasting recovery mode.

[0131] If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0132] Understandably, when the first timing duration exceeds the first set duration, it indicates that the vehicle's time in the first delay mode is long enough, and the initial preload torque output by the motor is sufficient to reduce the abnormal noises caused by sudden torque changes, thus exiting the first delay mode. If the first timing duration is less than or equal to the first set duration, without pressing the brake pedal or accelerator pedal, it indicates that the motor still needs to continuously output the initial preload torque to reduce the abnormal noises caused by sudden torque changes.

[0133] This configuration can further improve control precision and accuracy, and further reduce the energy consumption of pure electric vehicles.

[0134] The initial set duration is an empirical value obtained from extensive prior testing. This initial set duration varies depending on the type of pure electric vehicle and its size.

[0135] Among them, such as Figure 2 As shown, after the vehicle depresses and releases the brake pedal in regenerative braking mode, steps S600 to S800 are also included.

[0136] The S600 determines whether the vehicle enters the second delay mode based on whether the brake pedal is pressed and the rate of change of the brake pedal depth, whether the accelerator pedal is pressed and the rate of change of the accelerator pedal depth, the current gear status, and the current vehicle speed.

[0137] Specifically, the steps for determining whether a vehicle has entered the second delay mode based on whether the brake pedal is depressed and the rate of change in brake pedal depth, whether the accelerator pedal is depressed and the rate of change in accelerator pedal depth, the current gear position, and the current vehicle speed include:

[0138] Steps S610 to S630 are preferably performed simultaneously.

[0139] S610: Determine whether the brake pedal is currently pressed.

[0140] If the brake pedal is pressed, the vehicle will remain in regenerative braking mode.

[0141] S620: Determine whether the accelerator pedal is currently pressed.

[0142] If the accelerator pedal is pressed, the vehicle enters drive mode.

[0143] S630: Determine if the vehicle is currently in neutral.

[0144] If the vehicle's current gear is returned to neutral, the vehicle will be controlled to enter the initial mode. Specifically, when the vehicle's current gear is returned to neutral, it is determined that the driver intends to stop, and the vehicle will be controlled to enter the initial mode.

[0145] If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then proceed to step S640. At this time, the accelerator pedal depth change rate is zero.

[0146] S640: Determine whether the current vehicle speed is within the second set vehicle speed range; determine whether the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate.

[0147] If the current vehicle speed is within the second set speed range, and the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate, the vehicle enters the second delay mode. Execute S700.

[0148] By determining whether the vehicle has entered the second delay mode based on the vehicle's current speed and the absolute value of the rate of change of the brake pedal depth, the system ensures that in regenerative braking mode, the vehicle only enters the second delay mode to adjust the motor's output torque when a sudden torque change causes a significant abnormal noise. Compared to existing technologies that directly control the motor's output torque to approach zero when a sudden torque change occurs, this system further improves the accuracy and precision of the vehicle's transition from regenerative braking mode to the second delay mode.

[0149] The second set speed range is an empirical value obtained from extensive prior testing. This second set speed range varies for different types of pure electric vehicles and for pure electric vehicles of different sizes.

[0150] The second set rate of change is an empirical value obtained from a large number of previous experiments.

[0151] Specifically, the first set speed range and the second set speed range may be the same or different, or they may partially overlap; the first set change rate and the second set change rate may be the same or different.

[0152] If the current vehicle speed is not within the second set speed range, and / or the absolute value of the brake pedal depth change rate is less than the second set change rate, then the vehicle's driving mode is determined based on the current vehicle speed.

[0153] Understandably, if the current vehicle speed is not within the second set speed range, it means that in regenerative braking mode, the current speed is not enough to cause a large abnormal noise when the vehicle experiences a sudden change in torque. If the absolute value of the rate of change of brake pedal depth is less than the first set rate of change, it means that the driver did not press the brake pedal very hard. In this case, the sudden change in vehicle torque is relatively smooth and will not cause a large abnormal noise when the torque changes.

[0154] This setting can further improve the accuracy and precision of the vehicle entering the second delay mode, and can also further reduce the electrical energy consumed when adjusting the sudden torque change, thereby further reducing the energy consumption of pure electric vehicles.

[0155] Specifically, the steps for determining the vehicle's driving mode based on the current vehicle speed include:

[0156] Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery.

[0157] If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle will enter the coasting recovery mode.

[0158] If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0159] S700, start timing for the second timing duration; at the same time, determine the second required preload torque based on the vehicle's current speed; the motor outputs the second required preload torque.

[0160] Specifically, assuming the vehicle transitions from regenerative braking mode to the second delayed mode, a second cur is generated based on the vehicle speed and the second required preload torque obtained from extensive prior testing. The second required preload torque is then determined from this second cur based on the vehicle's current speed.

[0161] Preferably, in the second delay mode, as the vehicle's current speed changes, the value of the optimal second required preload torque will also change accordingly, so that the optimal second required preload torque can be matched in real time according to the vehicle's current speed. At this time, controlling the vehicle to drive according to the optimal second required preload torque can better reduce the phenomenon of abnormal noise caused by sudden torque changes in the vehicle.

[0162] As an alternative, assuming the vehicle transitions from regenerative braking mode to the second delay mode, a second table of vehicle speed and required preload torque can be obtained from extensive prior testing. The required preload torque can then be retrieved from this second table based on the vehicle speed when entering the second delay mode.

[0163] S800 determines whether the vehicle should exit the second delay mode based on the second timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed.

[0164] Specifically, the steps for determining whether the vehicle has exited the second delay mode based on the second timing duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed include:

[0165] Steps S810, S820, and S830 are preferably performed simultaneously.

[0166] S810: Real-time detection of whether the brake pedal is pressed.

[0167] If the brake pedal is pressed, the vehicle will remain in regenerative braking mode.

[0168] S820: Real-time detection of whether the accelerator pedal is pressed.

[0169] If you press the accelerator pedal, the vehicle will enter drive mode.

[0170] S830: Determine whether the second timing duration is greater than the second set duration.

[0171] If the second timeout duration exceeds the second set duration, exit the second delay mode.

[0172] After exiting the second delay mode, determine whether the brake pedal is pressed; determine whether the accelerator pedal is pressed.

[0173] If neither the brake pedal nor the accelerator pedal is pressed, the vehicle's driving mode is determined based on the current speed.

[0174] Specifically, the steps for determining the vehicle's driving mode based on the current vehicle speed include:

[0175] Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery.

[0176] If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle will enter the coasting recovery mode.

[0177] If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0178] Understandably, when the second timing duration exceeds the second set duration, it indicates that the vehicle remains in the second delay mode long enough that the second required preload torque output by the motor is sufficient to reduce the abnormal noises caused by sudden torque changes, thus exiting the second delay mode. If the second timing duration is less than or equal to the second set duration, without pressing the brake or accelerator pedals, it indicates that the motor needs to continuously output the second required preload torque to reduce the abnormal noises caused by sudden torque changes.

[0179] This configuration can further improve control precision and accuracy, and further reduce the energy consumption of pure electric vehicles.

[0180] The second set duration is an empirical value obtained from a large number of previous tests. The second set duration varies for different types of pure electric vehicles and pure electric vehicles of different sizes.

[0181] The process includes steps S900 to S1200 after the vehicle enters the coasting recovery mode.

[0182] Steps S900 to S1200 are preferably performed simultaneously.

[0183] S900: Real-time detection of whether the brake pedal is pressed.

[0184] If you press the brake pedal, the vehicle will enter regenerative braking mode.

[0185] S1000: Real-time detection of whether the accelerator pedal is pressed.

[0186] If you press the accelerator pedal, the vehicle will enter drive mode.

[0187] S1100: Real-time detection of whether the vehicle is in neutral.

[0188] If the vehicle's current gear is shifted back to neutral, the vehicle will be controlled to enter the initial mode.

[0189] S1200: Real-time judgment of whether the vehicle speed is greater than or equal to the set speed for coasting recovery.

[0190] If the vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle will remain in coasting recovery mode.

[0191] If the vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

[0192] In order to avoid the inaccuracy in determining the vehicle's driving mode when the accelerator pedal is pressed before the brake pedal is fully released, the pure electric vehicle drivetrain control method also includes:

[0193] If the accelerator pedal is pressed before the brake pedal is fully released, the vehicle will be put into regenerative braking mode.

[0194] This design effectively avoids situations where the accelerator pedal is pressed before the brake pedal is fully released, which could lead to an inaccurate determination of the vehicle's driving mode. It also further enhances the driving safety of pure electric vehicles and ensures the driver's safety.

[0195] This configuration ensures that the vehicle only enters a delay mode to adjust the motor's output torque when a sudden torque change causes a significant abnormal noise. Compared to existing technologies that directly control the motor's output torque to near zero when a sudden torque change occurs, this effectively improves the accuracy and precision of the vehicle entering the delay mode and also reduces the energy consumption of pure electric vehicles.

[0196] Therefore, by controlling pure electric vehicles through this pure electric vehicle transmission system control method, the control precision and accuracy are high, which can effectively improve the phenomenon of abnormal noise caused by sudden torque changes in the vehicle, reduce the energy consumption of pure electric vehicles, effectively improve driving comfort, enhance user experience, and ensure driver safety.

[0197] The specific control methods for the vehicle in crawl mode, the specific control methods for the vehicle in regenerative braking mode, and the specific control methods for the vehicle in coasting regenerative braking mode are all existing technologies and will not be described in detail here.

[0198] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the implementation of the present invention. Those skilled in the art will be able to make various obvious changes, readjustments, and substitutions without departing from the scope of protection of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the claims of the present invention.

Claims

1. A control method for the transmission system of a pure electric vehicle, characterized in that, include: When the accelerator pedal is released in drive mode or the brake pedal is released in regenerative braking mode, the system determines whether the vehicle enters a delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed. If the vehicle enters the delay mode, a timer begins and lasts for a specified duration. Simultaneously, the required preload torque is determined based on the vehicle's current speed, and the motor outputs the required preload torque. The vehicle is determined to exit the delay mode based on the timeout duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed. The delay mode includes a first delay mode, the timing duration includes a first timing duration, and the required preload torque includes a first required preload torque. When the accelerator pedal is released in drive mode, the specific steps for determining whether the vehicle has entered the delay mode based on whether the brake pedal is depressed and the rate of change of brake pedal depth, whether the accelerator pedal is depressed and the rate of change of accelerator pedal depth, the current gear position, and the current vehicle speed include: Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed; determine if the vehicle is currently in neutral. If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then determine whether the current vehicle speed is within the first set speed range; and whether the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change. If the current vehicle speed is within the first set vehicle speed range, and the absolute value of the rate of change of the accelerator pedal depth is greater than or equal to the first set rate of change, then the vehicle enters the first delay mode. If the vehicle enters the first delay mode, the timing begins and is the first timing duration; at the same time, the first required preload torque of the vehicle is determined based on the current vehicle speed; the motor outputs the first required preload torque. The specific steps for determining whether a vehicle should exit the first delay mode when it enters the first delay mode, based on the timeout duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed, include: Real-time detection of whether the brake pedal is pressed; real-time detection of whether the accelerator pedal is pressed; determination of whether the first timing duration is greater than the first set duration; If the brake pedal is pressed, or the accelerator pedal is pressed, or the first timer duration exceeds the first set duration, then exit the first delay mode.

2. The pure electric vehicle transmission system control method according to claim 1, characterized in that, After exiting the first delay mode, the pure electric vehicle drive system control method further includes: Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed. If neither the brake pedal nor the accelerator pedal is pressed, the vehicle's driving mode is determined based on the current speed.

3. The pure electric vehicle transmission system control method according to claim 2, characterized in that, Determining the vehicle's driving mode based on the current speed includes: Determine if the current vehicle speed is greater than or equal to the set speed for coasting recovery; If the current vehicle speed is greater than or equal to the coasting recovery set speed, the vehicle enters the coasting recovery mode; If the current vehicle speed is less than the set speed for coasting recovery, the vehicle enters crawl mode.

4. The pure electric vehicle transmission system control method according to claim 3, characterized in that, Once the vehicle enters coasting recovery mode, the following steps are also included: Real-time detection of whether the brake pedal is pressed; If you press the brake pedal, the vehicle will enter regenerative braking mode; Real-time detection of whether the accelerator pedal is pressed; If the accelerator pedal is pressed, the vehicle enters the aforementioned driving mode; Real-time detection of whether the vehicle is in neutral; If the vehicle's current gear is returned to neutral, the vehicle will be controlled to enter the initial mode; Real-time detection of whether the vehicle speed is greater than or equal to the set speed for coasting recovery; If the vehicle speed is greater than or equal to the set speed for coasting recovery, the vehicle maintains the coasting recovery mode; If the vehicle speed is less than the set speed for coasting recovery, the vehicle enters the crawl mode.

5. The pure electric vehicle drivetrain control method according to any one of claims 1-4, characterized in that, The delay mode also includes a second delay mode, the timing duration also includes a second timing duration, and the required preload torque also includes a second required preload torque. When the vehicle releases the brake pedal in regenerative braking mode, the specific steps for determining whether the vehicle has entered the delay mode based on whether the brake pedal is pressed and the rate of change of brake pedal depth, whether the accelerator pedal is pressed and the rate of change of accelerator pedal depth, the current gear status, and the current vehicle speed include: Determine if the brake pedal is pressed; determine if the accelerator pedal is pressed; determine if the vehicle is currently in neutral. If the brake pedal is not currently depressed, the accelerator pedal is not depressed, and the vehicle is not currently in neutral, then determine whether the current vehicle speed is within the second set speed range; and whether the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate. If the current vehicle speed is within the second set vehicle speed range, and the absolute value of the brake pedal depth change rate is greater than or equal to the second set change rate, then the vehicle enters the second delay mode. If the vehicle enters the second delay mode, the timing begins for the second timing duration; at the same time, the second required preload torque of the vehicle is determined based on the current vehicle speed; the motor outputs the second required preload torque.

6. The pure electric vehicle drivetrain control method according to claim 5, characterized in that, When the vehicle enters the second delay mode, the specific steps for determining whether the vehicle should exit the delay mode based on the timeout duration, whether the brake pedal is pressed, and whether the accelerator pedal is pressed include: Real-time detection of whether the brake pedal is pressed; real-time detection of whether the accelerator pedal is pressed; determination of whether the second timing duration is greater than the second set duration; If the brake pedal is pressed, or the accelerator pedal is pressed, or the second timer duration exceeds the second set duration, then exit the second delay mode.

7. The pure electric vehicle drive system control method according to claim 1, characterized in that, The pure electric vehicle drivetrain control method also includes: Once the vehicle enters the initial mode, it determines whether to enter drive mode based on the vehicle's current gear position and whether the accelerator pedal is pressed.

8. The pure electric vehicle transmission system control method according to claim 7, characterized in that, The specific steps to determine whether the vehicle has entered drive mode based on its current gear position and whether the accelerator pedal is pressed include: Determine the vehicle's current gear; If the vehicle's current gear is not neutral or park, determine whether the accelerator pedal is pressed. If you press the accelerator pedal, the vehicle will enter drive mode.

9. The pure electric vehicle drive system control method according to claim 1, characterized in that, The pure electric vehicle drivetrain control method also includes: If the accelerator pedal is pressed before the brake pedal is fully released, the vehicle will be put into regenerative braking mode.

10. A pure electric vehicle, comprising a pure electric vehicle drivetrain, the pure electric vehicle drivetrain including a motor, a transmission mechanism, and wheels, wherein the input end of the transmission mechanism is connected to the output shaft of the motor, and the output end of the transmission mechanism is connected to the wheels, characterized in that, Used to implement the pure electric vehicle drive system control method according to any one of claims 1-9.

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