Vehicle gear shifting methods, devices, processors, and vehicles

Abstract

This invention discloses a method, apparatus, processor, and vehicle for adjusting vehicle gears. The method includes: acquiring the vehicle's speed during operation; determining a target gear information based on the speed; adjusting the wheel speeds and motor speeds based on the target gear information to obtain an adjustment result, wherein the adjustment result indicates that the wheel speeds and motor speeds are the same; and controlling the vehicle's two-speed reducer to adjust the vehicle's original gear to the target gear according to the target gear information. This invention solves the technical problem of poor stability during vehicle gear shifting.

Description

Technical Field

[0001] This invention relates to the field of vehicles, and more specifically, to a method, apparatus, processor, and vehicle for adjusting gears. Background Technology

[0002] Currently, vehicles typically use single-speed reducers for operation. However, the fixed gear ratio of a single-speed reducer makes it impossible to simultaneously achieve both power and fuel economy. Using a two-speed reducer allows the motor's operating points to be distributed more widely in the high-efficiency range by changing the gear ratio, thereby improving driving efficiency, reducing energy loss, and extending driving range. However, two-speed reducers can experience power interruptions during gear shifting, affecting vehicle power and smoothness. Therefore, the technical issue of poor stability during gear shifting remains.

[0003] There is currently no effective solution to the aforementioned technical problem of poor stability during vehicle gear shifting. Summary of the Invention

[0004] This invention provides a method, apparatus, processor, and vehicle for adjusting vehicle gears, in order to at least solve the technical problem of poor stability during vehicle gear shifting.

[0005] According to one aspect of the present invention, a method for adjusting the gear position of a vehicle is provided. The method may include: acquiring the vehicle's speed during operation; determining target gear information based on the speed; adjusting the wheel-end rotational speed and motor-end rotational speed of the vehicle based on the target gear information to obtain an adjustment result, wherein the adjustment result indicates that the wheel-end rotational speed and motor-end rotational speed are the same; and controlling the vehicle's two-speed reducer to adjust the vehicle's original gear to the target gear according to the target gear information based on the adjustment result.

[0006] Optionally, before adjusting the wheel speed and motor speed of the vehicle based on the target gear information to obtain the adjustment result, the method further includes: performing torque alternation processing on the front axle motor and the rear axle motor of the vehicle based on the target gear information; and controlling the two-speed reducer to adjust the original gear to neutral in response to the completion of the torque alternation processing.

[0007] Optionally, based on the target gear information, torque alternation processing is performed on the front axle motor and the rear axle motor of the vehicle, including: in response to the target gear information being sent to the front axle motor and the rear axle motor, determining a first target torque for the front axle motor and a second target torque for the rear axle motor, wherein the first target torque is determined based on the vehicle's required torque, and the second target torque is determined based on the required torque and the first target torque; transferring the first target torque to the rear axle motor to complete the torque alternation processing.

[0008] Optionally, in response to the completion of torque alternation processing, the two-speed reducer is controlled to adjust its original gear to neutral, including: sending a neutral request signal to the two-speed reducer; and in response to the two-speed reducer receiving the neutral request signal, adjusting its original gear to neutral and maintaining it for a target duration.

[0009] Optionally, based on the target gear information, the wheel-end speed and motor-end speed of the vehicle are adjusted to obtain the adjustment result, including: determining the rear axle speed of the vehicle's rear axle motor based on the vehicle's rear left axle speed and rear right axle speed, wherein the motor end includes the rear axle motor and the front axle motor; determining the target speed of the rear axle motor based on the vehicle's pre-accelerated axle speed and rear axle speed; determining the second target torque of the rear axle motor based on the target speed; and in response to the speed difference between the rear axle wheel end and the rear axle motor being less than a speed threshold, completing the adjustment of the wheel-end speed and motor-end speed, and generating the adjustment result, wherein the wheel end includes the rear axle wheel end and the front axle wheel end of the vehicle.

[0010] Optionally, based on the adjustment result, the two-speed reducer of the vehicle adjusts the original gear of the vehicle to the target gear according to the target gear information, including: based on the adjustment result, sending a target gear request signal to the two-speed reducer, wherein the target gear corresponds to the target gear signal; in response to the two-speed reducer receiving the target gear request signal, adjusting the neutral gear of the vehicle to the target gear, and maintaining it for a target duration.

[0011] Optionally, after the two-speed reducer receives a target gear request signal, adjusts the vehicle's neutral gear to the target gear, and maintains it for a target duration, the method further includes: after adjusting the neutral gear to the target gear, performing torque recovery on the first target torque of the front axle motor and the second target torque of the rear axle motor.

[0012] According to another aspect of the present invention, a vehicle gear adjustment device is also provided. The device may include: an acquisition unit for acquiring the vehicle's speed during operation; a determination unit for determining a target gear information of the vehicle based on the speed; an adjustment unit for adjusting the wheel-end rotational speed and the motor-end rotational speed of the vehicle based on the target gear information to obtain an adjustment result, wherein the adjustment result indicates that the wheel-end rotational speed and the motor-end rotational speed are the same; and a control unit for controlling the vehicle's two-speed reducer to adjust the vehicle's original gear to the target gear according to the target gear information based on the adjustment result.

[0013] According to another aspect of the present invention, a computer-readable storage medium is also provided. The computer-readable storage medium includes a stored program, wherein, when the program is executed, it controls the device where the computer-readable storage medium is located to perform the gear shifting method of the vehicle according to the present invention.

[0014] According to another aspect of the present invention, a processor is also provided. The processor is configured to run a program, wherein the program, when running, executes the vehicle gear adjustment method of the present invention.

[0015] According to another aspect of the present invention, a vehicle is also provided. This vehicle is used to perform the gear shifting method of the vehicle according to the embodiments of the present invention.

[0016] In this embodiment of the invention, the vehicle's speed during operation is acquired; based on the speed, the target gear information is determined; based on the target gear information, the wheel speeds and motor speeds are adjusted to obtain an adjustment result, where the adjustment result indicates that the wheel speeds and motor speeds are the same; based on the adjustment result, the vehicle's two-speed reducers are controlled to adjust the vehicle's original gear to the target gear according to the target gear information. In other words, in this embodiment of the invention, the vehicle's speed during operation can be monitored in real time, and the target gear information is determined based on the speed. The wheel speeds and motor speeds can be adjusted to be the same according to the target gear information, and after adjustment, based on the adjustment result, the two-speed reducers are controlled to adjust the vehicle's original gear to the target gear according to the target gear information. Since power interruption can occur when a vehicle uses a two-speed reducer for gear shifting, resulting in poor vehicle power and smoothness, the problem of shock or power interruption during gear shifting can be solved by adjusting the wheel speed to match the motor speed. This addresses the technical issue of poor stability during gear shifting and improves the stability of the vehicle during gear shifting. Attached Figure Description

[0017] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this application, illustrate exemplary embodiments of the invention and, together with their description, serve to explain the invention and do not constitute an undue limitation thereof. In the drawings:

[0018] Figure 1 This is a flowchart of a vehicle gear adjustment method according to an embodiment of the present invention;

[0019] Figure 2 This is a schematic diagram of a vehicle rear axle equipped with a two-speed reducer according to an embodiment of the present invention.

[0020] Figure 3 This is a schematic diagram illustrating the slope change of torque according to an embodiment of the present invention;

[0021] Figure 4 This is a schematic diagram illustrating another variation in the slope of the torque according to an embodiment of the present invention;

[0022] Figure 5 This is a schematic diagram of a vehicle gear adjustment device according to an embodiment of the present invention. Detailed Implementation

[0023] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0024] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0025] Example 1

[0026] According to an embodiment of the present invention, an embodiment of a method for adjusting the gear position of a vehicle is provided. It should be noted that the steps shown in the flowchart in the accompanying drawings can be executed in a computer system such as a set of computer-executable instructions. Furthermore, although a logical order is shown in the flowchart, in some cases, the steps shown or described may be executed in a different order than that shown here.

[0027] Figure 1 This is a flowchart of a vehicle gear adjustment method according to an embodiment of the present invention, such as... Figure 1 As shown, the method may include the following steps:

[0028] Step S102: Obtain the vehicle's speed during the driving process.

[0029] In the technical solution provided in step S102 of the present invention, the vehicle can be a pure electric vehicle, such as a pure electric four-wheel drive car. Driving speed, also known as vehicle speed, can be used to characterize the vehicle's driving state.

[0030] In this embodiment, during vehicle operation, the vehicle's driving status can be identified, and the appropriate gear can be determined based on the vehicle's speed.

[0031] Optionally, before acquiring the vehicle's speed during operation, it's possible to check if the vehicle is powered on. After powering on, the vehicle's gears can be initialized. For example, the gear information stored when the vehicle was last powered off can be read as the vehicle's initial gear information. Timing begins after power-on; when the time exceeds a time threshold t, gear initialization is considered complete. The value of the time threshold t can be determined after calibration for different vehicles. It should be noted that this is merely an illustrative example, and no specific restrictions are placed on the determination method or value of the time threshold.

[0032] Optionally, after the gear initialization is completed, the initial gear can be called the original gear, and the target gear can be identified based on the monitored vehicle driving status.

[0033] Step S104: Determine the target gear information of the vehicle based on the driving speed.

[0034] In the technical solution provided in step S104 of the present invention, the target gear information can be information corresponding to the target gear that matches the current vehicle speed, and can be the name of the target gear, such as first forward gear (D1) and second forward gear (D2). It should be noted that this is only an example and does not impose specific limitations on the expression form of the target gear information.

[0035] In this embodiment, after obtaining the vehicle's speed during driving, it is possible to determine which target gear corresponds to the speed, thereby determining the target gear information corresponding to the current speed.

[0036] For example, when the vehicle's speed is less than v1, the target gear information could be D1. When the vehicle's speed is greater than v2, the target gear information could be D2. When the vehicle's speed is within the range [v1, v2], the target gear information can remain unchanged from the previous time step. Here, v1 and v2 are related to the vehicle's driving model and the characteristic curve of the vehicle's drive motor to ensure the driver's driving style and that the motor's efficiency is within the optimal range. Driving modes can include Sport mode, Comfort mode, and Eco mode. It should be noted that the specific modes included in the above driving models are only illustrative and are not specifically limited here.

[0037] Step S106: Based on the target gear information, adjust the wheel speed and motor speed of the vehicle to obtain the adjustment result.

[0038] In the technical solution of step S106 of the present invention, the adjustment result can be used to indicate that the wheel end speed and the motor end speed are the same. The wheel end speed can be the speed of the rear axle wheel end of the vehicle. The motor end speed can be the speed of the rear axle motor of the vehicle. It should be noted that the above wheel end speed and motor end speed are only illustrative examples and are not specifically limited here.

[0039] In this embodiment, after determining the target gear information of the vehicle based on the driving speed, the speed of the rear axle wheel end and the speed of the rear axle motor end of the vehicle can be adjusted based on the target gear information so that the speeds of the two are the same, that is, the speed synchronization is achieved.

[0040] Optionally, before synchronizing the speed at the rear axle wheel end with the speed at the rear axle motor end, a torque alternation phase can be performed first, that is, the torque of the motor at the front axle of the vehicle is transferred to the motor at the rear axle of the vehicle, thereby ensuring that there is no power interruption during gear shifting.

[0041] Optionally, after the torque alternation phase, a neutral (N) shift phase can be performed to adjust the original gear to neutral.

[0042] Optionally, after completing the neutral gear shift, the speed adjustment phase can be initiated. The speed adjustment phase primarily aims to synchronize the rotational speeds of the rear axle wheels and the rear axle motor, thereby reducing the impact force during gear shifting and improving the smoothness of gear transitions.

[0043] During the process of adjusting the vehicle's gears using a two-speed reducer, power interruption can occur, affecting the vehicle's power and smoothness. Therefore, the technical problem of poor stability during gear shifting persists. However, in this embodiment of the invention, by synchronizing the rotational speeds of the rear axle wheels and the rear axle motor during the speed adjustment phase, the impact during gear engagement is reduced, thereby improving the smoothness of gear shifting and ultimately enhancing the stability of the vehicle during gear shifting.

[0044] Step S108: Based on the adjustment result, control the vehicle's two-speed reducer to adjust the vehicle's original gear to the target gear according to the target gear information.

[0045] In the technical solution of step S108 of the present invention, the target gear can be a gear that matches the current driving speed of the vehicle.

[0046] In this embodiment, after adjusting the wheel end speed and the motor end speed to be consistent based on the target gear information, the vehicle's two-speed reducer can be controlled to adjust the vehicle's original gear to the target gear.

[0047] Optionally, based on the adjustment results, the system can proceed to the target gear engagement stage. In this stage, a gear request signal for the target gear can be sent to the two-speed reducers. Based on this gear request signal, the vehicle's gear is adjusted to the target gear. When the actual gear status reported by the two-speed reducers changes to the target gear and remains so for a certain period, the target gear engagement stage is considered complete, and the system can proceed to the next torque recovery stage. In this stage, the torque of the front axle motor and the rear axle motor can be adjusted.

[0048] Steps S102 to S108 of this application can monitor the vehicle's speed in real time and determine the target gear information based on the speed. The vehicle's wheel speed and motor speed can be adjusted to be the same according to the target gear information. After adjustment, the two-speed reducer is controlled to adjust the vehicle's original gear to the target gear according to the target gear information. Since power interruption can occur during gear shifting using a two-speed reducer, leading to poor vehicle power and smoothness, adjusting the wheel speed and motor speed to be the same can solve the problem of shock or power interruption during gear shifting. This solves the technical problem of poor stability during gear shifting and improves the stability of the vehicle during gear shifting.

[0049] The method described in this embodiment will be further described below.

[0050] As an optional embodiment, in step S106, before adjusting the wheel speed and motor speed of the vehicle based on the target gear information to obtain the adjustment result, the method further includes: performing torque alternation processing on the front axle motor and the rear axle motor of the vehicle based on the target gear information; and controlling the two-speed reducer to adjust the original gear to neutral in response to the completion of the torque alternation processing.

[0051] In this embodiment, before adjusting the wheel axle speed and motor speed based on the target gear information, torque alternation processing can be performed on the front axle motor and the rear axle motor of the vehicle based on the target gear information. After the torque alternation processing is completed, the two-speed reducer is controlled to adjust the original gear to neutral. The front axle motor can be called the front drive (Technological Motor, abbreviated as TM) motor, and can be referred to as TM1. The rear axle motor can be called the rear drive motor, and can be referred to as TM2.

[0052] Optionally, before adjusting the speed at the motor end and the wheel end, a torque alternation stage and a neutral (N) shift stage are also included.

[0053] When adjusting vehicle gears using a two-speed reducer, a technical problem arises where power interruption can occur. However, in this embodiment of the invention, the torque of the front axle motor can be transferred to the rear axle motor during the torque alternation phase, ensuring no power interruption during gear shifting and thus achieving the technical effect of avoiding power interruption.

[0054] As an optional embodiment, step S106 involves performing torque alternation processing on the front axle motor and the rear axle motor of the vehicle based on the target gear information. This includes: in response to the target gear information being sent to the front axle motor and the rear axle motor, determining a first target torque for the front axle motor and a second target torque for the rear axle motor, wherein the first target torque is determined based on the vehicle's required torque, and the second target torque is determined based on the required torque and the first target torque; and transferring the first target torque to the rear axle motor to complete the torque alternation processing.

[0055] In this embodiment, during the torque alternation process between the front axle motor and the rear axle motor of the vehicle based on target gear information, the target gear information can be sent to both the front and rear axle motors to determine a first target torque for the front axle motor and a second target torque for the rear axle motor. The first target torque is then transferred from the front axle motor to the rear axle motor, completing the torque alternation process. The first target torque is determined based on the vehicle's required torque and can be the target torque for the front motor. The second target torque is determined based on the required torque and the first target torque and can be the target torque for the rear motor, such as the target torque for the rear left motor. The required torque can be the torque required by the driver in the vehicle, or simply the driver's required torque.

[0056] Optionally, during the torque alternation phase, the target gear information, as well as the target torque of the front motor and the target torque of the rear left motor, can be sent to the front axle motor and the rear axle motor. The target torque of the front motor can be the driver's required torque of the front motor transitioning to 0 torque at a certain slope.

[0057] Optionally, the target torque of the rear left motor = the driver's required torque of the rear motor + the driver's required torque of the front motor - the target torque of the front motor.

[0058] Optionally, the driver's required torque for the front motor = total driver's required torque × (1 - inter-axle distribution coefficient); the driver's required torque for the rear motor = total driver's required torque × inter-axle distribution coefficient, wherein the total driver's required torque can be determined by looking up a table based on the vehicle's throttle and speed. The inter-axle distribution coefficient (inter-axle torque distribution coefficient) can be determined based on the vehicle's driving state. It should be noted that in this embodiment of the invention, the value of the inter-axle distribution coefficient is not displayed and can be preset to 0.5. When torque alternates, the inter-axle torque distribution coefficient can transition from the current value of 0.5 to 0 with a constant slope. When the vehicle is in front-wheel drive mode, the inter-axle torque distribution coefficient can be set to 0.

[0059] Alternatively, torque zeroing can be achieved using a segmented filtering method, which directly zeroes the torque of the drive motor, resulting in a significant impact and affecting driving smoothness.

[0060] Alternatively, the filtering method can be as follows: when the filtered torque changes near 0, slow down the rate of change of torque; when the torque before filtering and the torque after filtering are less than a certain value, slow down the rate of change of torque; under other operating conditions, the torque should change according to a certain slope.

[0061] Optionally, during the torque alternation phase, a gear request signal for the original gear can be sent to the two-speed reducer. Once the actual torque of the current motor is less than 3 Nm, it can be considered that the torque alternation phase is complete, and the vehicle can enter the neutral (N) gear shift phase.

[0062] As an optional embodiment, step S106, in response to the completion of torque alternation processing, controls the two-speed reducer to adjust the original gear to neutral, including: sending a neutral request signal to the two-speed reducer; in response to the two-speed reducer receiving the neutral request signal, adjusting the original gear to neutral, and continuing for a target duration.

[0063] In this embodiment, after the torque alternation is completed, a neutral request signal can be sent to the two-speed reducer. After the two-speed reducer detects that it has received the neutral request signal, the original gear can be adjusted to neutral and maintained for a target duration, wherein the target duration can be set to t1.

[0064] Optionally, during the N gear engagement phase, target torque and the original gear position signal can be sent to the front and rear axle motors of the vehicle, where the target torque for the rear motor is 0. The target torque for the front motor can be the total torque required by the driver. At this time, the gear request signal sent to the two-speed reducer is N. When the actual gear position status fed back by the two-speed reducer changes to N and remains so for a time t1, it indicates that the N gear engagement phase is complete, and the speed adjustment phase can begin.

[0065] As an optional embodiment, step S106 involves adjusting the wheel-end speed and motor-end speed of the vehicle based on the target gear information to obtain an adjustment result. This includes: determining the rear axle speed of the vehicle's rear axle motor based on the vehicle's rear left axle speed and rear right axle speed, wherein the motor end includes the rear axle motor and the front axle motor; determining the target speed of the rear axle motor based on the vehicle's pre-accelerated axle speed and rear axle speed; determining the second target torque of the rear axle motor based on the target speed; and, in response to the speed difference between the rear axle wheel end and the rear axle motor being less than a speed threshold, completing the adjustment of the wheel-end speed and motor-end speed and generating an adjustment result, wherein the wheel end includes the rear axle wheel end and the front axle wheel end of the vehicle.

[0066] In this embodiment, during the adjustment of the wheel-end speed and motor-end speed based on the target gear information, the rear axle speed of the vehicle's rear axle motor can be determined based on the rear left and right speeds and the rear right axle speed. The target speed of the rear axle motor is determined based on the pre-accelerated axle speed and the rear axle speed. Based on the target speed, a second target torque of the rear axle motor can be determined. When the speed difference between the rear axle wheel-end and the rear axle motor is less than a speed threshold, the adjustment of the wheel-end speed and motor-end speed can be completed, obtaining the adjustment result. The motor-end can include both the rear axle motor and the front axle motor. The wheel-end can include both the rear axle wheel-end and the front axle wheel-end.

[0067] Optionally, during the speed adjustment phase, the main focus is to synchronize the speed of the rear axle wheel end with that of the rear axle motor end in order to reduce the impact of engaging the target gear and improve the smoothness of gear shifting.

[0068] Optionally, the target speed of the rear axle motor is calculated. The target speed can consist of two parts: the rear axle speed and the pre-increased shaft speed. The rear axle speed can be determined using the following formula:

[0069] n r =(n rl +n rr ) / 2

[0070] Where, n r It can be used to indicate the rear axle speed of the rear axle motor; n rl It can be used to indicate the speed of the rear left shaft; n rr It can be used to indicate the speed of the rear right shaft.

[0071] Alternatively, the target rotational speed can be determined using the following formula:

[0072] n tgt =n r +n pre

[0073] Where, n tgt It can be used to indicate the target speed of the rear axle motor; n pre It can be used to represent the pre-accelerated axle speed, which can be obtained by looking up a table based on the vehicle's current speed and acceleration.

[0074] Optionally, the rear axle motor can be made to rotate at the target speed for closed-loop speed difference control. Furthermore, the target torque of the rear axle motor can be calculated using the following formula:

[0075] T tgt =k p ×(n TM2 -n tgt )+k i ×∫(n TM2 -n tgt )

[0076] Among them, T tgt It can be used to represent the target torque of the rear axle motor; n TM2 It can be used to indicate the speed of the rear axle motor; k p The proportional gain, which can be used to represent the proportional gain of a linear controller (PI controller), can be determined through actual vehicle calibration; k i This can be used to represent the integral coefficient of a PI controller, and can be determined through actual vehicle calibration; n TM2 This can be the actual speed of the rear axle motor.

[0077] Optionally, the target torque of the front motor can be the total torque required by the driver. In this case, the gear request signal sent to the two-speed reducer is N. When the speed difference between the rear axle wheel end and the rear axle motor end is <n...thd When n is reached, it indicates that the speed adjustment phase has ended and the target gear can be engaged. thd It is the speed difference between the actual speed and the target speed. The value can be determined through actual vehicle calibration, for example, it can be 0-100 rpm.

[0078] As an optional embodiment, step S108, based on the adjustment result, controls the two-speed reducer of the vehicle to adjust the original gear of the vehicle to the target gear according to the target gear information, including: based on the adjustment result, sending a target gear request signal to the two-speed reducer, wherein the target gear corresponds to the target gear signal; in response to the two-speed reducer receiving the target gear request signal, adjusting the neutral gear of the vehicle to the target gear, and maintaining it for a target duration.

[0079] In this embodiment, during the process of controlling the two-speed reducer of the vehicle to adjust the original gear of the vehicle to the target gear according to the target gear information based on the adjustment result, a target gear request signal can be sent to the two-speed reducer based on the adjustment result. When the two-speed reducer receives the target gear request signal, it can adjust the neutral gear of the vehicle to the target gear and maintain it for a target time. The target gear can correspond to the target gear signal.

[0080] Optionally, during the target gear engagement phase, a target gear request signal can be sent to the two-speed reducer. When the actual gear status fed back by the reducer changes to the target gear and remains so for a duration of t1, the target gear engagement phase is completed, and the torque recovery phase can then begin.

[0081] As an optional embodiment, in step S108, after the two-speed reducer receives a target gear request signal, adjusts the vehicle's neutral gear to the target gear, and maintains it for a target duration, the method further includes: after adjusting the neutral gear to the target gear, performing torque recovery on the first target torque of the front axle motor and the second target torque of the rear axle motor.

[0082] In this embodiment, after the neutral gear is adjusted to the target gear, the first target torque of the front axle motor and the second target torque of the rear axle motor can be restored.

[0083] Optionally, the target torque of the front axle motor during the torque recovery phase is the target torque at the moment of disengagement during the target gear engagement phase, adjusted according to a certain slope, to transition the torque required by the driver to the front axle motor.

[0084] Optionally, the target torque of the rear axle motor = the driver's required torque of the rear axle motor + the driver's required torque of the front axle motor - the target torque of the front axle motor.

[0085] Optionally, the driver's required torque for the front axle motor = total driver's required torque × (1 - inter-axle distribution coefficient); the driver's required torque for the rear axle motor = total driver's required torque × inter-axle distribution coefficient, wherein the total driver's required torque can be determined by referring to a table based on throttle and vehicle speed. The inter-axle distribution coefficient can be determined based on the vehicle's driving conditions. In this embodiment of the invention, the inter-axle distribution coefficient can be set to 0.5. When torque recovers, the inter-axle torque distribution coefficient can transition from 0 to the target value of 0.5 with a constant slope.

[0086] Optionally, if the drive motor torque is directly reset to zero, it will generate a large impact, thereby affecting the smoothness of vehicle driving. However, in this embodiment of the invention, to avoid the above-mentioned problem, the torque recovery slope can be achieved by using a segmented filtering method to prevent the impact caused by directly resetting the drive motor torque to zero.

[0087] Optionally, the filtering method can be as follows: when the filtered torque changes near 0, the rate of change of torque is slowed down; when the torque before filtering and the torque after filtering are less than a certain value, the rate of change of torque is slowed down; under other operating conditions, the torque changes according to a certain slope.

[0088] In this embodiment of the invention, the vehicle's speed can be monitored in real time, and the target gear information can be determined based on the speed. The wheel speed and motor speed can be adjusted to be the same according to the target gear information. After adjustment, the two-speed reducer is controlled to adjust the vehicle's original gear to the target gear according to the target gear information. Since power interruption can occur during gear shifting using a two-speed reducer, leading to poor vehicle power and smoothness, aligning the wheel speed and motor speed can resolve the impact or power interruption during gear shifting. This solves the technical problem of poor stability during gear shifting and improves the stability of the vehicle during gear shifting.

[0089] Example 2

[0090] The technical solutions of the embodiments of the present invention will be illustrated below with reference to preferred embodiments.

[0091] Currently, pure electric vehicles typically use single-speed reduction, and the fixed gear ratio makes it impossible to simultaneously achieve both power and fuel economy. Using a two-speed reducer allows the motor's operating points to be distributed more widely in the high-efficiency range by changing the gear ratio, thereby improving drive system efficiency, reducing system energy loss, and extending driving range. However, two-speed reducers experience power interruption during gear shifts, affecting the vehicle's power and smoothness. Only shifting without power interruption can meet the higher demands of electric vehicles.

[0092] One related technology proposes a two-speed automatic transmission for electric vehicles and its shift control method. This addresses the problem in existing technologies where the shifting process between forward and reverse gears involves the impact of the overrunning clutch, affecting shifting comfort and shortening the overrunning clutch's lifespan. This new method transforms the shifting process into an automatic engagement process using a clutch plate, eliminating power interruption during shifting. Furthermore, a pre-engagement process eliminates the impact of the overrunning clutch during shifting, improving shifting comfort and driving smoothness. This method uses gear pairs for power transmission, resulting in high transmission efficiency. Furthermore, providing two forward gears increases the likelihood of the motor operating in its high-efficiency range, leading to higher energy utilization and increased vehicle range under the same conditions. However, due to the unavoidable issue of poor smoothness during shifting, the technical problem of poor stability during vehicle shifting still exists.

[0093] In another related technology, a shifting system for a pure electric vehicle equipped with a two-speed transmission is proposed. The vehicle controller is connected to the two-speed transmission system and inputs gear control signals to it. The two-speed transmission system has a manual shifting mechanism installed inside the vehicle, which inputs gear control signals to the transmission system. The vehicle controller is connected to a manual shift switch, which inputs a signal indicating manual or automatic transmission mode to the controller. This shifting system and method allow the user to manually control the transmission gears and select the appropriate gear based on actual road conditions, which helps improve vehicle smoothness and range. However, since poor smoothness is unavoidable during gear shifting, the technical problem of poor stability during vehicle gear shifting still exists.

[0094] However, this invention proposes a two-speed reducer control method for a pure electric four-wheel drive vehicle. This method can monitor the vehicle's speed in real time and determine the target gear information based on the speed. The method adjusts the wheel speed and motor speed to be the same according to the target gear information. After adjustment, the two-speed reducer is controlled to adjust the vehicle's original gear to the target gear. Since power interruption can occur during gear shifting using a two-speed reducer, leading to poor vehicle power and smoothness, this method addresses the impact or power interruption during gear shifting by aligning the wheel speed and motor speed. This solves the technical problem of poor stability during gear shifting and improves overall vehicle stability.

[0095] The embodiments of the present invention will be further described below.

[0096] Figure 2 This is a schematic diagram of a vehicle rear axle equipped with a two-speed reducer according to an embodiment of the present invention, as shown below. Figure 2 As shown, the vehicle may include a two-speed reducer 201, a rear drive motor 202, a front drive motor 203, and a power battery 204. The problem of power interruption during gear shifts is solved by controlling the torque of the front and rear motors, ensuring the vehicle's power performance; the impact problem during gear shifts is solved by controlling the motor speed, thus improving the vehicle's smoothness. In this embodiment of the invention, the configuration with a two-speed shock absorber mounted on the rear axle is used as an example; the control principle is the same for the configuration with a two-speed shock absorber mounted on the front axle.

[0097] In this embodiment of the invention, the module for controlling the two-speed reducer may include a gear decision module and a gear switching control module.

[0098] In this embodiment, the gear selection module can initialize the target gear after the vehicle is powered on. After initialization, the gear information stored during the last power-off can be read as the current target gear. Timing begins after the vehicle is powered on, and initialization is complete after a time > t. The target gear is then identified based on the vehicle's driving status, where t can be determined based on actual vehicle calibration.

[0099] Optionally, when the vehicle speed is <v1, the target gear is D1; ​​when the vehicle speed is >v2, the target gear is D2; when the vehicle speed is in the range [v1, v2], the target gear remains unchanged from the previous moment. Here, v1 and v2 are related to the vehicle's driving mode and the drive motor's characteristic curve, taking into account the driver's driving style and ensuring the motor operates within its optimal efficiency range. The driving model typically includes Sport mode, Comfort mode, and Eco mode.

[0100] In this embodiment, the gear shifting control module can take upshifting control when the target gear changes from D1 to D2 as an example. Upshifting control includes stages such as alternating torque between the front and rear axles, shifting to neutral (N), speed adjustment (deceleration), shifting to D2, and torque recovery. The downshifting control method when the target gear changes from D2 to D1 is similar to the upshifting control method and will not be described again.

[0101] Optionally, during the torque alternation phase, the torque of the front axle motor can be transferred to the rear axle motor to ensure that there is no power interruption during gear shifting, thereby achieving the technical effect of avoiding power interruption.

[0102] Optionally, during the torque alternation phase, the target gear information, as well as the target torque of the front motor and the target torque of the rear left motor, can be sent to the front axle motor and the rear axle motor. The target torque of the front motor can be the driver's required torque of the front motor transitioning to 0 torque at a certain slope.

[0103] Optionally, the target torque of the rear left motor = the driver's required torque of the rear motor + the driver's required torque of the front motor - the target torque of the front motor.

[0104] Optionally, the driver's required torque for the front motor = total driver's required torque × (1 - inter-axle distribution coefficient); the driver's required torque for the rear motor = total driver's required torque × inter-axle distribution coefficient, wherein the total driver's required torque can be determined by looking up a table based on the vehicle's throttle and speed. The inter-axle distribution coefficient (inter-axle torque distribution coefficient) can be determined based on the vehicle's driving state. It should be noted that in this embodiment of the invention, the value of the inter-axle distribution coefficient is not displayed and can be preset to 0.5. When torque alternates, the inter-axle torque distribution coefficient can transition from the current value of 0.5 to 0 with a constant slope. When the vehicle is in front-wheel drive mode, the inter-axle torque distribution coefficient can be set to 0.

[0105] Optionally, Figure 3 This is a schematic diagram illustrating the slope change of torque according to an embodiment of the present invention, as shown below. Figure 3 As shown, torque can be zeroed using a segmented filtering method. Directly zeroing the torque of the drive motor will generate a large impact and affect the smoothness of driving. The filtering method can be as follows: (1) When the filtered torque changes near 0, slow down the rate of torque change; (2) When the torque before filtering and the torque after filtering are less than a certain value, slow down the rate of torque change; (3) Under other operating conditions, the torque should change according to a certain slope.

[0106] Optionally, during the torque alternation phase, a gear request signal for the original gear can be sent to the two-speed reducer. Once the actual torque of the current motor is less than 3 Nm, it can be considered that the torque alternation phase is complete, and the vehicle can enter the neutral (N) gear shift phase.

[0107] Optionally, during the N gear engagement phase, target torque can be sent to both the front and rear axle motors. The target torque for the rear motor is 0; the target torque for the front motor is the total torque required by the driver. The gear request signal sent to the two-speed reducer is N. When the actual gear position feedback from the two-speed reducer changes to N and remains so for a duration of t_1, the N gear engagement phase is complete, and the speed reduction and adjustment phase begins.

[0108] Optionally, the speed adjustment stage mainly aims to synchronize the speed of the rear axle wheel end and the rear axle motor end, so as to reduce the impact of shifting into D2 gear and improve the smoothness of gear shifting.

[0109] Optionally, firstly, calculate the target speed of the rear axle motor. The target speed consists of two parts: the rear axle speed and the pre-increased shaft speed. The rear axle speed can be determined using the following formula:

[0110] n r =(n rl +n rr ) / 2

[0111] Where, n r It can be used to indicate the rear axle speed of the rear axle motor; n rl It can be used to indicate the speed of the rear left shaft; n rr It can be used to indicate the speed of the rear right shaft.

[0112] Alternatively, the target rotational speed can be determined using the following formula:

[0113] n tgt =n r +n pre

[0114] Where, n tgt It can be used to indicate the target speed of the rear axle motor; n pre It can be used to represent the pre-accelerated axle speed, which can be obtained by looking up a table based on the vehicle's current speed and acceleration.

[0115] Optionally, the rear axle motor can be made to rotate at the target speed for closed-loop speed difference control. Furthermore, the target torque of the rear axle motor can be calculated using the following formula:

[0116] T tgt =k p ×(n TM2 -n tgt )+k i ×∫(n TM2 -n tgt )

[0117] Among them, T tgt It can be used to represent the target torque of the rear axle motor; n TM2 It can be used to indicate the speed of the rear axle motor; k p The proportional gain, which can be used to represent the proportional gain of a linear controller (PI controller), can be determined through actual vehicle calibration; k i This can be used to represent the integral coefficient of a PI controller, and can be determined through actual vehicle calibration; n TM2 This can be the actual speed of the rear axle motor.

[0118] Optionally, the target torque of the front motor can be the total torque required by the driver. In this case, the gear request signal sent to the two-speed reducer is N. When the speed difference between the rear axle wheel end and the rear axle motor end is <n...thd When n is reached, it indicates that the speed adjustment phase has ended and the target gear can be engaged. thd It is the speed difference between the actual speed and the target speed. The value can be determined through actual vehicle calibration, for example, it can be 0-100 rpm.

[0119] Optionally, the gear request signal sent to the two-speed reducer during the D2 gear engagement phase is D2. When the actual gear status fed back by the two-speed reducer changes to D2 and remains so for a period of t_1, the D2 gear engagement phase is completed, and the torque recovery phase begins.

[0120] Optionally, the target torque of the front axle motor during the torque recovery phase is the target torque at the moment of disengagement during the target gear engagement phase, adjusted according to a certain slope, to transition the torque required by the driver to the front axle motor.

[0121] Optionally, the target torque of the rear axle motor = the driver's required torque of the rear axle motor + the driver's required torque of the front axle motor - the target torque of the front axle motor.

[0122] Optionally, the driver's required torque for the front axle motor = total driver's required torque × (1 - inter-axle distribution coefficient); the driver's required torque for the rear axle motor = total driver's required torque × inter-axle distribution coefficient, wherein the total driver's required torque can be determined by referring to a table based on throttle and vehicle speed. The inter-axle distribution coefficient can be determined based on the vehicle's driving conditions. In this embodiment of the invention, the inter-axle distribution coefficient can be set to 0.5. When torque recovers, the inter-axle torque distribution coefficient can transition from 0 to the target value of 0.5 with a constant slope.

[0123] Optionally, Figure 4 This is a schematic diagram illustrating another variation in the slope of the torque according to an embodiment of the present invention, as shown below. Figure 4 As shown, if the drive motor torque is directly reset to zero, it will generate a large impact, thereby affecting the smoothness of vehicle driving. However, in this embodiment of the invention, in order to avoid the above problem, the torque recovery slope can be adopted by segmented filtering to prevent the impact caused by the direct reset of the drive motor torque to zero. The filtering method can be as follows: (1) when the filtered torque changes near 0, the torque change rate is slowed down; (2) when the torque before filtering and the torque after filtering are less than a certain value, the torque change rate is slowed down; (3) under other operating conditions, the torque changes according to a certain slope.

[0124] In this embodiment of the invention, the vehicle's speed can be monitored in real time, and the target gear information can be determined based on the speed. The wheel speed and motor speed can be adjusted to be the same according to the target gear information. After adjustment, the two-speed reducer is controlled to adjust the vehicle's original gear to the target gear according to the target gear information. Since power interruption can occur during gear shifting using a two-speed reducer, leading to poor vehicle power and smoothness, aligning the wheel speed and motor speed can resolve the impact or power interruption during gear shifting. This solves the technical problem of poor stability during gear shifting and improves the stability of the vehicle during gear shifting.

[0125] Example 3

[0126] According to an embodiment of the present invention, a vehicle gear shifting device is also provided. It should be noted that this vehicle gear shifting device can be used to perform the vehicle gear shifting method in Embodiment 1.

[0127] Figure 5 This is a schematic diagram of a vehicle gear shifting device according to an embodiment of the present invention. Figure 5 As shown, the gear adjustment device 500 of the vehicle may include: an acquisition unit 502, a determination unit 504, an adjustment unit 506, and a control unit 508.

[0128] The acquisition unit 502 is used to acquire the vehicle's speed during the driving process.

[0129] The determining unit 504 is used to determine the target gear information of the vehicle based on the driving speed.

[0130] The adjustment unit 506 is used to adjust the wheel end speed and the motor end speed of the vehicle based on the target gear information to obtain the adjustment result, wherein the adjustment result is used to indicate that the wheel end speed and the motor end speed are the same.

[0131] The control unit 508 is used to control the vehicle's two-speed reducer to adjust the vehicle's original gear to the target gear according to the target gear information, based on the adjustment results.

[0132] Optionally, the device may further include: a first processing unit for performing torque alternation processing on the front axle motor and the rear axle motor of the vehicle based on the target gear information; and a first control unit for controlling the two-speed reducer to adjust the original gear to neutral in response to the completion of the torque alternation processing.

[0133] Optionally, the first processing unit may include: a first determining module, configured to determine a first target torque of the front axle motor and a second target torque of the rear axle motor in response to the target gear information being sent to the front axle motor and the rear axle motor, wherein the first target torque is determined based on the vehicle's required torque and the second target torque is determined based on the required torque and the first target torque; and a transfer module, configured to transfer the first target torque to the rear axle motor to complete the torque alternation process.

[0134] Optionally, the first control unit may include: a first sending module for sending a neutral request signal to the two-speed reducer; and a first adjustment module for adjusting the original gear to neutral in response to the two-speed reducer receiving the neutral request signal, and maintaining it for a target duration.

[0135] Optionally, the adjustment unit 506 may include: a second determining module, used to determine the rear axle speed of the vehicle's rear axle motor based on the vehicle's rear left axle speed and the vehicle's rear right axle speed, wherein the motor end includes the rear axle motor and the front axle motor; a third determining module, used to determine the target speed of the rear axle motor based on the vehicle's pre-accelerated axle speed and the rear axle speed; a fourth determining module, used to determine the second target torque of the rear axle motor based on the target speed; and a processing module, used to adjust the wheel end speed and the motor end speed in response to the speed difference between the rear axle wheel end and the rear axle motor being less than a speed threshold, and to generate an adjustment result, wherein the wheel end includes the rear axle wheel end and the vehicle's front axle wheel end.

[0136] Optionally, the control unit 508 may include: a second sending module, configured to send a target gear request signal to the two-speed reducer based on the adjustment result, wherein the target gear corresponds to the target gear signal; and a second adjustment module, configured to adjust the vehicle's neutral gear to the target gear in response to the two-speed reducer receiving the target gear request signal, and maintain the adjustment for the target duration.

[0137] Optionally, the device may further include a recovery unit for restoring the first target torque of the front axle motor and the second target torque of the rear axle motor after the neutral gear is adjusted to the target gear.

[0138] In this embodiment of the invention, the vehicle's speed during driving is acquired by an acquisition unit; the target gear information of the vehicle is determined by a determination unit based on the driving speed; the wheel speed and motor speed of the vehicle are adjusted by an adjustment unit based on the target gear information to obtain an adjustment result, wherein the adjustment result indicates that the wheel speed and motor speed are the same; and the vehicle's two-speed reducer is controlled by a control unit based on the adjustment result to adjust the vehicle's original gear to the target gear according to the target gear information, thereby solving the technical problem of poor stability during vehicle gear shifting and achieving the technical effect of improving stability during vehicle gear shifting.

[0139] Example 4

[0140] According to an embodiment of the present invention, a computer-readable storage medium is also provided, the storage medium including a stored program, wherein the program executes the vehicle gear adjustment method of Embodiment 1.

[0141] Example 5

[0142] According to an embodiment of the present invention, a processor is also provided for running a program, wherein the program executes the vehicle gear adjustment method of Embodiment 1 during runtime.

[0143] Example 6

[0144] According to an embodiment of the present invention, a vehicle is also provided for performing the gear shifting method of the vehicle according to the embodiment of the present invention.

[0145] The sequence numbers of the above embodiments of the present invention are for descriptive purposes only and do not represent the superiority or inferiority of the embodiments.

[0146] In the above embodiments of the present invention, the descriptions of each embodiment have different focuses. For parts not described in detail in a certain embodiment, please refer to the relevant descriptions of other embodiments.

[0147] In the several embodiments provided in this application, it should be understood that the disclosed technical content can be implemented in other ways. The device embodiments described above are merely illustrative; for example, the division of units can be a logical functional division, and in actual implementation, there may be other division methods. For instance, multiple units or components may be combined or integrated into another system, or some features may be ignored or not executed. Furthermore, the displayed or discussed mutual coupling, direct coupling, or communication connection may be through some interfaces; the indirect coupling or communication connection between units or modules may be electrical or other forms.

[0148] The units described as separate components may or may not be physically separate. The components shown as units may or may not be physical units; that is, they may be located in one place or distributed across multiple units. Some or all of the units can be selected to achieve the purpose of this embodiment according to actual needs.

[0149] Furthermore, the functional units in the various embodiments of the present invention can be integrated into one processing unit, or each unit can exist physically separately, or two or more units can be integrated into one unit. The integrated unit can be implemented in hardware or as a software functional unit.

[0150] If the integrated unit is implemented as a software functional unit and sold or used as an independent product, it can be stored in a computer-readable storage medium. Based on this understanding, the technical solution of the present invention, in essence, or the part that contributes to the prior art, or all or part of the technical solution, can be embodied in the form of a software product. This computer software product is stored in a storage medium and includes several instructions to cause a computer device (which may be a personal computer, server, or network device, etc.) to execute all or part of the steps of the methods described in the various embodiments of the present invention. The aforementioned storage medium includes various media capable of storing program code, such as USB flash drives, read-only memory (ROM), random access memory (RAM), portable hard drives, magnetic disks, or optical disks.

[0151] The above description is only a preferred embodiment of the present invention. It should be noted that for those skilled in the art, several improvements and modifications can be made without departing from the principle of the present invention, and these improvements and modifications should also be considered within the scope of protection of the present invention.

Claims

1. A method for adjusting the gear position of a vehicle, characterized in that, include: Obtain the vehicle's speed during operation; Based on the driving speed, the target gear information of the vehicle is determined; Based on the target gear information, the front axle motor and the rear axle motor of the vehicle are subjected to torque alternation processing. In response to the completion of the torque alternation process, the two-speed reducer of the vehicle is controlled to adjust the original gear of the vehicle to neutral. The rear axle speed of the rear axle motor is determined based on the rear left axle speed and the rear right axle speed of the vehicle. Based on the vehicle's pre-accelerated axle speed and the rear axle speed, the target speed of the rear axle motor is determined; Based on the target rotational speed, the second target torque of the rear axle motor is determined; In response to the speed difference between the rear axle wheel end and the rear axle motor of the vehicle being less than a speed threshold, the speed of the wheel end and the speed of the motor end are adjusted, and an adjustment result is generated. The adjustment result indicates that the speed of the wheel end and the speed of the motor end are the same. The motor end includes the rear axle motor and the front axle motor, and the wheel end includes the rear axle wheel end and the front axle wheel end of the vehicle. Based on the adjustment results, a target gear request signal is sent to the two-speed reducers. In response to the two-speed reducer receiving the target gear request signal, the original gear position is adjusted from neutral to the target gear. After adjusting the neutral gear to the target gear and maintaining the target gear for the target duration, torque recovery is performed on the first target torque of the front axle motor and the second target torque of the rear axle motor. The torque recovery employs segmented filtering, which includes: slowing down the torque change rate when the torque before filtering and the torque after filtering are less than a certain value, or when the torque after filtering changes within a preset range of zero; and in other operating conditions, the torque changes according to a preset slope.

2. The method according to claim 1, characterized in that, Based on the target gear information, the front axle motor and the rear axle motor of the vehicle are subjected to torque alternation processing, including: In response to the target gear information being sent to the front axle motor and the rear axle motor, a first target torque for the front axle motor and a second target torque for the rear axle motor are determined, wherein the first target torque is determined based on the required torque of the vehicle, and the second target torque is determined based on the required torque and the first target torque; The first target torque is transferred to the rear axle motor to complete the torque alternation process.

3. The method according to claim 1, characterized in that, In response to the completion of the torque alternation process, controlling the two-speed reducer to adjust the original gear to neutral includes: Send a neutral request signal to the two-speed reducers; In response to the two-speed reducer receiving the neutral request signal, the original gear is adjusted to neutral and maintained for the target duration.

4. A gear shifting device for a vehicle, characterized in that, include: The acquisition unit is used to acquire the vehicle's speed during the driving process; A determining unit is used to determine the target gear information of the vehicle based on the driving speed; The device is further configured to perform torque alternation processing on the front axle motor and the rear axle motor of the vehicle based on the target gear information; and in response to the completion of the torque alternation processing, control the two-speed reducer of the vehicle to adjust the original gear of the vehicle to neutral. An adjustment unit is used to determine the rear axle speed of the rear axle motor based on the rear left axle speed and the rear right axle speed of the vehicle. Based on the vehicle's pre-accelerated axle speed and the rear axle speed, the target speed of the rear axle motor is determined; based on the target speed, the second target torque of the rear axle motor is determined. In response to the speed difference between the rear axle wheel end and the rear axle motor of the vehicle being less than a speed threshold, the speed of the wheel end and the speed of the motor end are adjusted, and an adjustment result is generated. The adjustment result indicates that the speed of the wheel end and the speed of the motor end are the same. The motor end includes the rear axle motor and the front axle motor, and the wheel end includes the rear axle wheel end and the front axle wheel end of the vehicle. The control unit is configured to send a target gear request signal to the two-speed reducer based on the adjustment result; and in response to the two-speed reducer receiving the target gear request signal, adjust the original gear from neutral to the target gear. The device is further configured to perform torque recovery on the first target torque of the front axle motor and the second target torque of the rear axle motor after adjusting the neutral gear to the target gear and maintaining the target gear for the target duration. The torque recovery employs segmented filtering, which includes: slowing down the torque change rate when the torque before filtering and the torque after filtering are less than a certain value or when the torque after filtering changes within a preset range of zero; and in other operating conditions, the torque changes according to a preset slope.

5. A processor, characterized in that, The processor is used to run a program, wherein the program is executed by the processor to perform the method according to any one of claims 1 to 3.

6. A vehicle, characterized in that, Used to perform the method according to any one of claims 1 to 3.

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