Shift control method, vehicle controller, vehicle, and storage medium

Abstract

A shift control method includes determining (110) a torque exchange time length and a total clutch required torque T0 of a torque exchange phase, and gradually decreasing (120) a shift torque Toff assigned to a clutch to be disengaged and gradually increasing (130) a shift torque Ton assigned to a clutch to be engaged, so as to satisfy Toff+Ton=T0, within the torque exchange time length, wherein Ton and Toff are set to change nonlinearly within the torque exchange time length to suppress the effect of changes in the response speed of the torque control system on the smoothness of the torque exchange. Further disclosed are a vehicle controller, a vehicle, and a storage medium.

Description

[Technical Field]

[0001] The present disclosure relates to, but is not limited to, the field of vehicle shifting technology. [Background technology]

[0002] Shifting is required during vehicle operation, and can be achieved by synchronously controlling the disengagement of the offgoing clutch and the engagement of the oncoming clutch. While the performance of shift control has a significant impact on drivability, the smoothness of the current shift process still needs to be improved. Summary of the Invention

[0003] The following provides a brief summary of the subject matter detailed herein, but is not intended to limit the scope of the claims. [Means for solving the problem]

[0004] One embodiment of the present disclosure provides a shift control method, the motor control method comprising: determining a torque exchange time length and a total clutch torque demand T0 for a torque exchange phase; Gradually decreasing the shift torque Toff assigned to the clutch to be disengaged and gradually increasing the shift torque Ton assigned to the clutch to be engaged within the torque exchange time length, and satisfying Toff+Ton=T0; Ton and Toff are set to change nonlinearly within the torque exchange time length in order to suppress the influence of changes in the response speed of the torque control system on the smoothness of torque exchange.

[0005] One embodiment of the present disclosure further provides a vehicle controller, the vehicle controller comprising: a processor and a storage device storing a computer program; When the processor executes the computer program, it can realize the shift control method described in any of the embodiments of the present disclosure.

[0006] An embodiment of the present disclosure further provides a vehicle, the vehicle including a vehicle controller according to any embodiment of the present disclosure.

[0007] One embodiment of the present disclosure further provides a non-transitory computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, can realize the shift control method described in any of the embodiments of the present disclosure.

[0008] In the above-described embodiments of the present disclosure, the shift torque assigned to the disengaging clutch and the shift torque assigned to the engaging clutch vary nonlinearly during the torque exchange phase, thereby allowing the clutch hydraulic system to adapt to respond to nonlinear changes in the torque exchange process and enhancing the smoothness of the shift process. [Brief explanation of the drawings]

[0009] Other aspects may be appreciated after reading and understanding the drawings and detailed description. [Figure 1] FIG. 1 is a schematic diagram of a hybrid vehicle in series mode according to one embodiment of the present disclosure. [Figure 2] FIG. 1 is a schematic diagram of a hybrid vehicle in parallel mode according to one embodiment of the present disclosure. [Figure 3] FIG. 1 is a schematic diagram of a hybrid architecture according to one embodiment of the present disclosure. [Figure 4] 4 is a flowchart of a shift control method according to one embodiment of the present disclosure. [Figure 5A] 10 is a graph of the progress percentage of an on-coming clutch without correction. [Figure 5B]10 is a graph of the progress percentage of an on-coming clutch after correction according to an embodiment of the present disclosure. [Figure 5C] 10 is a graph of the progress percentage of the clutch to be separated without correction. [Figure 5D] 10 is a graph of the progress percentage of the clutch to be separated after correction according to an embodiment of the present disclosure. [Figure 6] FIG. 2 is a schematic diagram of oil pressure changes during a refueling phase according to one embodiment of the present disclosure. [Figure 7] 1 is a hardware configuration diagram of a shift control device according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE INVENTION

[0010] Hereinafter, the technical solutions in the embodiments of the present disclosure will be clearly and completely described with reference to the drawings of the embodiments of the present disclosure. Obviously, the described embodiments are only some embodiments of the present disclosure, and not all embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by those skilled in the art without any creative work fall within the scope of protection of the present disclosure.

[0011] In describing the present disclosure, words such as "exemplary" or "for example" are used to denote an example, illustration, or explanation. Any embodiment described in the present disclosure as "exemplary" or "for example" should not be construed as preferred or advantageous over other embodiments. "And / or" in this specification describes a relationship between related objects and means that a three-way relationship can exist; for example, A and / or B can represent three cases: A exists alone, A and B exist simultaneously, and B exists alone. In describing the present disclosure, "plurality" means at least two, e.g., two, three, etc., unless otherwise specified and limited.

[0012] Note that directional designations (e.g., up, down, left, right, front, rear) in the embodiments of the present disclosure are used only to describe the relative positional relationships, movement situations, etc. between components in a specific position (as shown in the drawings) and do not indicate or imply that the indicated structure has a specific orientation, is constructed in a specific orientation, or is operated in a specific orientation. If the specific position changes, the directional designation also changes accordingly. Therefore, they should not be understood as limitations on the present disclosure. Furthermore, in the embodiments of the present disclosure, terms such as "first," "second," etc. are used for descriptive purposes only and should not be understood as indicating or implying the relative importance of, or implicitly indicating the number of, the technical features shown. Therefore, a feature defining "first" or "second" may explicitly or implicitly include at least one feature.

[0013] In the present disclosure, the terms "connected," "fixed," and the like should be understood in a broad sense unless otherwise clearly specified and limited. For example, unless otherwise limited, "fixed" may mean a fixed connection, a detachable connection, or an integral connection, a mechanical connection, an electrical connection, a direct connection, an indirect connection via an intermediate medium, an internal connection between two elements, or an interactive relationship between two elements. Those skilled in the art will be able to understand the specific meaning of the above terms in this specification depending on the context.

[0014] In this disclosure, the technical solutions in each embodiment may be combined with each other, but this must be based on what a person skilled in the art can achieve. If the combination of technical solutions is inconsistent or cannot be achieved, it should be considered that such combination of technical solutions does not exist and does not fall within the scope of protection claimed by this disclosure.

[0015] As fuel economy and emissions requirements become increasingly stringent and electrification systems continue to develop, hybrid technology is key to achieving energy savings and reducing emissions. To adapt and meet emissions requirements, automakers and parts suppliers are seeking solutions. Currently, hybrid systems are widely adopted due to the complexity and high cost of battery technology in pure electric vehicle technology systems.

[0016] The shift control method according to the embodiment of the present disclosure is shown in FIGS. 2 The present invention can be applied to a hybrid vehicle shown in FIG. 1. A two-motor hybrid system has three modes: pure electric mode, series mode, and parallel mode, and the hybrid vehicle can switch between these modes. As shown in the figure, the hybrid vehicle includes a first power mechanism including a connected engine 1 (denoted as ICE in the figure) and a first motor 2 (denoted as P1 in the figure), and a second power mechanism including a second motor 3 (denoted as P2 in the figure). A clutch 4 (denoted as C0 in the figure) for mode switching is connected between the first motor 2 and the second motor 3. FIG. 1 is a schematic diagram of the drive system of a hybrid vehicle in series mode. In series mode, the clutch 4 is in a disengaged state, and the engine 1 supplies power to the battery 6 and the second motor 3 via the first motor 2, and the second motor 3 drives the wheels via the transmission 5. FIG. 2 is a schematic diagram of the drive system of a hybrid vehicle in parallel mode. In parallel mode, the clutch 4 is in an engaged state (also called a coupled state), and both the engine 1 and the second motor 3 drive the wheels via the transmission 5.

[0017] The shift control method of the present disclosure can be applied to the hybrid architecture shown in FIG. 3. As shown, this hybrid architecture includes a first power mechanism, a second power mechanism, and a transmission mechanism. The first power mechanism includes a connected engine ICE and a first motor P1, and the second power mechanism includes a second motor P2. The transmission mechanism includes a fourth clutch C0 for mode switching, a second-row planetary gear set, and a first clutch B1, a second clutch B2, and a third clutch C3 for shift control. The second-row planetary gear set includes a first planetary gear set consisting of a first sun gear S1, a first carrier PC1, and a first ring gear R1, and a second planetary gear set consisting of a second sun gear S2, a second carrier PC2, and a second ring gear R2.

[0018] As shown in the figure, the output shaft of the first motor P1 can be connected to the second sun gear S2 via a fourth clutch C0 to drive the second sun gear S2. The output shaft of the second motor P2 can also be connected to the first sun gear S1 via a third clutch C3 to drive the first sun gear S1. The first sun gear S1 is connected to one end of the second clutch B2, and the other end of the second clutch B2 is connected to the hydraulic system. The first carrier PC1 is connected to the second ring gear R2, and both the first carrier PC1 and the second ring gear R2 are connected to one end of the first clutch B1, and the other end of the first clutch B1 is connected to the hydraulic system. The first ring gear R1 is connected to the second carrier PC2. Power input to the two-row planetary gear is transmitted to the wheel end from the output shaft connected to the first ring gear R1 and the second carrier PC2.

[0019] The hybrid architecture described above can achieve shifting among three forward gears. Among the first clutch B1, the second clutch B2, and the third clutch C3, first gear is achieved when only the first clutch B1 is engaged, second gear is achieved when only the second clutch B2 is engaged, and third gear is achieved when only the third clutch C3 is engaged. Shifting among gears can be achieved by disengaging one clutch (i.e., the disengaging clutch) and engaging the other clutch (i.e., the engaging clutch). The disengaging clutch is also called an active clutch, and the engaging clutch is also called a passive clutch. After the states of the disengaging clutch and the engaging clutch change, the transmission ratio changes due to a change in the power transmission path, thereby achieving a shift.

[0020] As can be understood, taking the first clutch B1 as an example, at a first time, it is the clutch to be separated and its separation is controlled, and at a second time, it is the clutch to be engaged and its engagement is controlled, where the first time and the second time represent different times and there is no difference between them in time. For example, currently, the first clutch B1 is engaged, and the second clutch B2 and the third clutch C3 are disengaged. When shifting from first to second gear, the first clutch B1 is controlled to be disengaged as the clutch to be separated, the second clutch B2 is controlled to be engaged as the clutch to be separated, and the third clutch C3 is not changed and controlled to remain disengaged. When shifting from second to third gear, the first clutch B1 is controlled to be disengaged, the second clutch B2 is controlled to be disengaged as the clutch to be separated, and the third clutch C3 is controlled to be engaged as the clutch to be separated.

[0021] Whether a hybrid vehicle is operating in series mode or parallel mode, it requires shift control. The performance of the shift control has a significant impact on drivability, and currently, the smoothness of the shift process needs to be improved. While the hybrid architectures to which the embodiments of the present disclosure are applicable have been described above, the shift control method of the embodiments of the present disclosure is not limited to a specific hybrid architecture, nor is it limited to hybrid vehicle shifting. It can also be used for electric and fuel-powered vehicles. In other power architectures, the shift control method of the embodiments of the present disclosure can be used in any case where one clutch is disengaged and another clutch is engaged.

[0022] In one embodiment, the shift process includes three stages. When the shift type is power on up and power off down, the three stages are sequentially: a fueling stage, a torque exchange stage, and a speed regulation stage. When the shift type is power on down and power off up, the three stages are sequentially: a fueling stage, a speed regulation stage, and a torque exchange stage. Here, power on up is also referred to as an accelerator upshift, power on down is also referred to as an accelerator downshift, power off up is also referred to as an accelerator release upshift, and power off down is also referred to as an accelerator release downshift.

[0023] Before the on-coming clutch engages, there is a certain gap between the driving part (e.g., driving disc) and the driven part (e.g., driven disc) of the clutch, and the oiling stage controls the oiling of the on-coming clutch to quickly eliminate this gap so that the on-coming clutch can reach a torque transmission state in a short time. The speed of oiling of the clutch and the pressure compliance after oiling are completed have a significant impact on drivability and power response during shifting.

[0024] In the torque exchange stage, the disengagement of the disengagement target clutch and the engagement of the engagement target clutch are performed synchronously, and the clutch torque is switched from the disengagement target clutch to the engagement target clutch.

[0025] During the speed regulation phase, the transmission control unit sends a down or up torque request to generate inertial torque, also known as speed regulation intervention torque, which changes the rotation speed of the power mechanism, such as the engine, until the target rotation speed is reached.

[0026] During the torque exchange phase, torque control for the disengaging and engaging clutches is performed at set time intervals and can be implemented based on a progress percentage, where the progress percentage is equal to the ratio of the current exchanged time length to the torque exchange time length (i.e., the time length of the torque exchange phase), and the current exchanged time length is equal to the difference between the current time and the start time of the torque exchange phase. In some exemplary embodiments, during torque exchange, the shift torques allocated to the disengaging and engaging clutches change linearly (i.e., the absolute value of the shift torque gradient does not change). Here, the shift torque allocated to the disengaging clutch decreases linearly over time, while the shift torque allocated to the engaging clutch increases linearly over time. However, the shift torque allocated to the clutches is the clutch's demand torque, and the actual torque generated when torque control is performed is also related to the response characteristics of the torque control system. For example, torque control systems respond differently to the same demand torque change at different control phases. Such a change in response speed can cause torque to rise, resulting in a "bump" phenomenon, which affects shift smoothness.

[0027] One embodiment of the present disclosure provides a shift control method, which includes steps 110 and 120, as shown in FIG.

[0028] In step 110, the torque exchange time length of the torque exchange phase and the total clutch torque demand T0 are determined.

[0029] In one exemplary embodiment of the present disclosure, the total clutch torque request may be equal to the torque request of the clutch to be disengaged before the torque exchange.

[0030] In step 120, within the torque exchange time length, the shift torque Toff assigned to the clutch to be disengaged is gradually decreased and the shift torque Ton assigned to the clutch to be engaged is gradually increased until Toff+Ton=T0 is satisfied.

[0031] Here, Ton and Toff are set to change nonlinearly within the torque exchange time length in order to suppress the effect of changes in the response speed of the torque control system on the smoothness of torque exchange.

[0032] In one exemplary embodiment of the present disclosure, the torque control system may have a fast response speed at the beginning of torque exchange and a slower response speed thereafter. In this case, the absolute value of the gradients of Ton and Toff may be controlled to first increase from a small value within the torque exchange time period, and the absolute value of the gradients of Ton and Toff may reflect the rate of change of Ton and Toff. In this case, the response speed of the hydraulic system is fast at the beginning, but the changes of Ton and Toff are slow, which may suppress the torque increase, avoid the bulging phenomenon, and improve shift smoothness. After the absolute value of the gradients of Ton and Toff increase from a small value, the response speed of the torque control system tends to stabilize. At this time, the rate of change of Ton and Toff may be maintained, and the rate of change of Ton and Toff may be slowed down to stabilize the later stage of torque exchange until the end. Throughout the torque exchange time period, the absolute value of the gradients of Ton and Toff may be set to other change modes, such as a change mode from small to large and then from large to small, a change mode that remains unchanged, or a change mode that goes from large to small and then remains unchanged.

[0033] In another exemplary embodiment of the present disclosure, the torque control system may have a slow response speed at the beginning of torque exchange and a fast response speed thereafter. In this case, the absolute values ​​of the gradients of Ton and Toff may be controlled to first decrease from large to small within the torque exchange time period. This may prevent torque increases due to changes in the response speed of the torque control system and facilitate smooth torque exchange. After the absolute values ​​of the gradients of Ton and Toff decrease from large to small, the absolute values ​​of the gradients of Ton and Toff may be set to a change mode in which they remain unchanged, a change mode from small to large, or another change mode.

[0034] In the shift control method of this embodiment, in order to reduce the impact of changes in the response speed of the torque control system on the smoothness of torque exchange, the shift torque assigned to the disengagement clutch and the engagement clutch is set to a nonlinear change based on the response characteristics of the torque control system rather than simply set to a linear change, thereby improving the smoothness of the shift process. The torque control system in the embodiments of the present disclosure refers to a torque control system for controlling clutch torque, and may be, but is not limited to, a hydraulic system.

[0035] In another exemplary embodiment of the present disclosure, the torque control system is hydraulic Control System The absolute values ​​of the gradients of Ton and Toff are set to initially increase from a small value within the torque exchange time period (e.g., monotonically increase). This setting is for a case where the response speed of the hydraulic system is fast at the start of torque exchange and then slows down, in order to suppress the effect of changes in the response speed of the hydraulic system on the smoothness of torque exchange at the start of torque exchange; the hydraulic system may be a hydraulic system. The absolute values ​​of the gradients of Ton and Toff can increase from a small value and then remain the same, or can decrease from a large value to a small value (e.g., monotonically decrease).

[0036] In one exemplary embodiment of the present disclosure, gradually decreasing the shift torque Toff assigned to the clutch to be disengaged and gradually increasing the shift torque Ton assigned to the clutch to be engaged within the torque exchange time length includes: The method includes: performing the following process at set time intervals within the torque exchange time length, obtaining an initial progress percentage based on a ratio between the currently exchanged time length and the torque exchange time length; correcting the initial progress percentage, and calculating Toff and Ton based on the corrected progress percentage and T0; Within the torque exchange time length, the absolute value of the gradient of the corrected progress percentage first goes from small to large and then goes from large to small, or first goes from small to large and then stays the same, and the current exchanged time length is equal to the current time minus the start time of the torque exchange phase.

[0037] In one example of this embodiment, correcting the initial progress percentage includes adding a current correction value to the initial progress percentage to obtain a corrected progress percentage, where the current correction value is calculated based on a trigonometric function that uses the initial progress percentage as an argument. For example, the current correction value is calculated using the following formula: X = sin(P0 × 0.0628) × k, where X is the current correction value, P0 is the initial progress percentage, and k is a correction coefficient that is determined based on the total clutch demand torque, for example, obtained by table lookup based on the total clutch demand torque. In this example, the torque exchange progress percentage is corrected by introducing a sine curve, but the sine function can be replaced with a cosine function or another function form that can change the absolute value of the slope of the corrected progress percentage from small to large.

[0038] In one example of the present disclosure, Toff and Ton calculated from the corrected progress percentage and T0 are Ton=T0×P′, Toff=T0×(100%− P’), and P' is the corrected progress percentage. There are many specific calculation processes for Toff and Ton. For example, Toff can be calculated and then subtracted from T0 to obtain Ton, or Ton can be calculated and then subtracted from T0 to obtain Toff, or Toff and Ton can be calculated directly using the formulas Ton=T0×P' and Toff=T0×(100-P'). P' may represent the corrected progress percentage of the disengagement clutch, and (100-P') may represent the corrected progress percentage of the engagement clutch.

[0039] In one example of the present disclosure, the corrected progress percentage of the clutch to be separated P'=((current replaced time length / torque replaced time length)×100+correction value)%, where (current replaced time length / torque replaced time length)×100 % is the initial progress percentage P, and the correction value = sin(initial progress percentage x 0.0628) x correction coefficient. The correction coefficient can be obtained by table lookup based on the total clutch required torque. The sum of the corrected progress percentages of the disengagement target clutch and the engagement target clutch is 100. % and by calculating the corrected percentage advance of one clutch, one can obtain the corrected percentage advance of the other clutch using direct subtraction.

[0040] FIG. 5A is a graph of the progress percentage of the on-coming clutch without compensation. FIG. 5B is a graph of the progress percentage of the on-coming clutch after compensation according to an embodiment of the present disclosure. FIG. 5C is a graph of the progress percentage of the off-going clutch without compensation. FIG. 5D is a graph of the progress percentage of the off-going clutch after compensation according to an embodiment of the present disclosure. It can be seen that the progress percentage curve after compensation according to an embodiment of the present disclosure exhibits sinusoidal characteristics, with a slow change in the beginning, a fast change in the middle, and a slow change in the end, i.e., the absolute value of the slope changes from small to large and back again. In addition to sinusoidal functions, other trigonometric functions, as well as continuous functions, discrete functions, or combinations of functions that can achieve this characteristic, can be used in embodiments of the present disclosure.

[0041] In another exemplary embodiment of the present disclosure, the progress percentage is calculated without any correction, and is calculated from the uncorrected progress percentage (i.e., the above-mentioned initial progress percentage) and T0 to obtain the shift torque assigned to the clutch to be separated and the shift torque assigned to the clutch to be engaged.The calculated shift torque assigned to the clutch to be separated is then corrected to obtain Toff, and the calculated shift torque assigned to the clutch to be engaged is corrected to obtain Ton, and Toff and Ton can be torque exchanged as the required torque assigned to the clutch to be separated and the clutch to be engaged, respectively.This method has the same effect as the method of correcting the progress percentage, and both are within the scope of protection of the present disclosure.

[0042] In an embodiment of the present disclosure, a progress percentage is obtained based on the ratio of the currently exchanged time length to the torque exchange time length, and the obtained progress percentage is corrected (e.g., by introducing a sinusoidal characteristic), and Toff and Ton are calculated based on the corrected progress percentage and T0. The absolute values ​​of the gradients of Ton and Toff can be small to large within the torque exchange time length, so that the shift torque assigned to the engaging clutch changes slowly in the beginning, quickly in the middle, and slowly in the end, thereby suppressing the bulging phenomenon caused by changes in the response speed of the torque control system and improving shift smoothness.

[0043] In one exemplary embodiment of the present disclosure, the torque exchange time length is obtained according to a process of the following steps.

[0044] In the first step, the corresponding torque exchange time lengths are obtained by the following methods.

[0045] In the first method, the torque exchange time length is obtained by table lookup based on the total clutch torque requirement and the input shaft rotational speed corresponding to the target gear. To prevent clutch overheating, the greater the total clutch torque requirement and the higher the input shaft rotational speed corresponding to the target gear, the shorter the time. Here, if the forward gears include 1st, 2nd, and 3rd gears, the target gear is 2nd or 3rd gear for power-on up and power-off up, and 1st or 2nd gear for power-on down and power-off down. Taking the hybrid architecture shown in Figure 3 as an example, the shaft connected to the second sun gear S2 of the two-row planetary gear in the figure and realizing power input is called the input shaft.

[0046] In the second method, a table lookup is performed based on the oil temperature of the hydraulic system to obtain a torque exchange time length, which is the maximum torque exchange time length allowed at the current oil temperature.

[0047] In a third method, a table lookup is performed based on the clutch temperature to obtain a torque exchange time length, which is the maximum torque exchange time length allowed for the current clutch temperature.

[0048] In the fourth method, the torque exchange time length is calculated based on the maximum clutch energy (based on the hardware setting), and the torque exchange time length is calculated as follows: maximum clutch energy value / (total clutch required torque x slip difference).

[0049] In the second step, the minimum value of all the obtained torque exchange time lengths is set as the final torque exchange time length, i.e., this torque exchange time length is used to calculate the shift torques assigned to the clutch to be disengaged and the clutch to be engaged.

[0050] When the shift torque of the clutch to be disengaged is equal to the total clutch torque demand, the torque exchange phase is completed and the speed regulation phase can be delayed for a period of time to ensure that the torque of the clutch to be disengaged is fully removed.

[0051] In one exemplary embodiment of the present disclosure, the method further includes, before the torque exchange stage, performing oil supply control in three stages, and oiling the clutch to be engaged using a first oil pressure, a second oil pressure, and a third oil pressure in a first stage, a second stage, and a third stage, respectively, wherein the third oil pressure is equal to a half-engagement point pressure of the clutch to be engaged, and the second oil pressure is greater than the third oil pressure and less than the first oil pressure.

[0052] In one example of this embodiment, the difference obtained by subtracting the second hydraulic pressure from the first hydraulic pressure is greater than the difference obtained by subtracting the third hydraulic pressure from the second hydraulic pressure. By setting the first hydraulic pressure to be larger, the oil supply speed can be increased and the time required for the oil supply phase can be shortened.

[0053] In one example of this embodiment, the duration of the first stage is less than the sum of the durations of the second and third stages so that the hydraulic pressure reaches the half-engagement pressure of the on-coming clutch sooner.

[0054] FIG. 6 shows a pressure control curve (ie, oil supply curve, clutch filling strategy diagram) of the on-coming clutch according to this embodiment, and as shown in the figure, the oil supply control process of this embodiment includes the following three stages in sequence.

[0055] The first stage (which can be referred to as the high-pressure oil supply stage) corresponds to period t1 in FIG. 6. As shown, the high-pressure oil supply stage uses a high first oil pressure to supply oil to the clutch in order to operate the solenoid valve, thereby enhancing the actual clutch pressure response. The duration of the high-pressure oil supply stage is shorter than the other two stages. The oil supply pressure (first oil pressure) and oil supply time used in the high-pressure oil supply stage are correlated with the oil temperature and can be determined based on the current oil temperature and the oil supply pressure and oil supply time calibrated at different oil temperatures. The oil supply pressure and oil supply time for this stage calibrated at different oil temperatures can be determined based on the measurement results.

[0056] The second stage (which can be referred to as the medium-pressure oil supply stage) corresponds to period t2 in Figure 6. As shown, during the medium-pressure oil supply stage, the second hydraulic pressure is used to supply oil to the clutch and allow oil to flow through the clutch's oil passage. The second hydraulic pressure is lower than the first hydraulic pressure and slightly higher than the clutch's half-engagement point (i.e., KP point). The difference between the first hydraulic pressure and the second hydraulic pressure is greater than the difference between the second hydraulic pressure and the third hydraulic pressure, ensuring that the clutch's supply pressure approaches the KP point pressure as quickly as possible. The oil supply pressure and oil supply time during the medium-pressure oil supply stage are correlated with oil temperature and can be determined based on the oil supply pressure and oil supply time for this stage, which are calibrated at oil temperatures different from the current oil temperature.

[0057] The third stage (which can be referred to as the low-pressure oil supply stage) corresponds to period t3 in Figure 6. As shown, during the low-pressure oil supply stage, the clutch is oiled using a third oil pressure, which is equal to the KP point pressure, and the clutch pressure reaches the KP point, preventing over-oiling. There will be differences in KP point pressure between different ambient temperatures and different samples. A single sample can be tested during the previous oil supply calibration, and calibration can be performed based on the test results. The clutch KP point pressure can then be determined through self-learning.

[0058] Each of the above steps may cause the transmission control unit or other control unit to send a corresponding hydraulic pressure request to a hydraulic control system that supplies oil to the clutch, and the hydraulic control system may generate the corresponding hydraulic pressure.

[0059] In this embodiment, the oil supply stage is divided into three stages: high-pressure oil supply, medium-pressure oil supply, and low-pressure oil supply. First, high-pressure oil supply is used to improve the clutch pressure response, then medium-pressure oil supply is used to bring the clutch oil pressure closer to the KP point pressure as quickly as possible, and finally low-pressure oil supply is used to bring the clutch pressure to the KP point. This embodiment's oil supply process is quick and stable, preventing over-oiling, and ensuring stable torque transmission at the initial shift stage, without any sense of instability, and allowing the shift process to be completed quickly.

[0060] During the torque exchange and speed adjustment stages of the shift process, hydraulic pressure control is required, as shown in the oil supply curve after time t3 in Figure 6. By controlling the hydraulic pressure at each stage of the shift process, the on-coming clutch can be smoothly engaged and pushed to lock, and the off-going clutch can be quickly released, ensuring power stability during the shift process.

[0061] During the torque exchange phase, the engagement of the on-coming clutch and the disengagement of the off-going clutch are synchronized, with the torque of the on-coming clutch gradually increasing and the torque of the off-going clutch gradually decreasing. When the torque exchange phase ends, the torque is already fully generated by the on-coming clutch. The shift process then enters the speed regulation phase, also known as the inertia phase.

[0062] The present disclosure further provides a vehicle controller, which includes a processor and a storage device storing a computer program, as shown in FIG. 7 , and when the processor executes the computer program, the vehicle controller can realize the shift control method described in any of the embodiments of the present disclosure. The vehicle controller can further include components such as a memory and a network interface. The vehicle controller can be a transmission control module, an overall control module, etc., and the present disclosure is not limited thereto.

[0063] The processor in the above embodiments of the present disclosure may be a general-purpose processor, including a central processor (CPU), a network processor (NP), a microprocessor, or other conventional processor. The processor may be a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field programmable gate array (FPGA), a discrete logic or other programmable logic device, a discrete gate or transistor logic device, a discrete hardware component, or other equivalent integrated or discrete logic circuit, or a combination of the above devices. That is, the processor in the above embodiments may be any processing device or combination of devices that implements the methods, steps, and logical block diagrams disclosed in the embodiments of the present disclosure. When the embodiments of the present disclosure are implemented partially in software, instructions for the software may be stored in a suitable non-volatile computer-readable storage medium, and one or more processors may be used to execute the instructions in hardware to perform the methods of the embodiments of the present disclosure. As used herein, the term "processor" may refer to the above structure or any other structure suitable for implementing the techniques described herein.

[0064] An embodiment of the present disclosure further provides a vehicle, the vehicle including the vehicle controller according to any embodiment of the present disclosure. In one example, the vehicle is a hybrid vehicle, and the disengaged clutch and the engaged clutch are clutches of a hybrid transmission. In another example, the vehicle may be a fuel-powered vehicle, an electric vehicle, or the like.

[0065] One embodiment of the present disclosure further provides a non-transitory computer-readable storage medium, wherein the computer-readable storage medium stores a computer program, which, when executed by a processor, can realize the shift control method described in any of the embodiments of the present disclosure.

[0066] In the one or more exemplary embodiments above, the functions described may be implemented in hardware, software, firmware, or any combination thereof. If implemented in software, the functions may be stored on or transmitted via a computer-readable medium as one or more instructions or code and executed by a hardware-based processing unit. A computer-readable medium may include a computer-readable storage medium corresponding to a tangible medium, such as a data storage medium, or a communication medium facilitating a computer program, such as any medium transferred from one place to another according to a communication protocol. In this manner, a computer-readable medium may generally correspond to a non-transitory tangible computer-readable storage medium or a communication medium, such as a signal or carrier wave. A data storage medium may be any available medium accessible by one or more computers or one or more processors to obtain instructions, code, and / or data structures for implementing the techniques described in this disclosure. A computer program product may include a computer-readable medium.

[0067] By way of example, and not limitation, such computer-readable storage media may include RAM, ROM, EEPROM, CD-ROM or other optical disk storage, magnetic disk storage or other magnetic storage, flash memory, or any other medium that can store desired program code in the form of instructions or data structures and that can be accessed by a computer. Also, any connection may be referred to as a computer-readable medium; for example, coaxial cable, fiber optic cable, twisted pair, digital subscriber line (DSL), or wireless technologies such as infrared, radio, or microwave are used to transmit instructions from a website, server, or other remote source, and the coaxial cable, fiber optic cable, twisted pair, DSL, or wireless technologies such as infrared, radio, or microwave are included within the definition of medium. It should be recognized, however, that computer-readable storage media and data storage media do not include connections, carrier waves, signals, or other transient media, but are instead intended to refer to non-transient tangible storage media. As used herein, magnetic disks and optical disks include compact disks (CDs), laser disks, optical disks, digital versatile disks (DVDs), floppy disks, Blu-ray disks, etc., where magnetic disks typically reproduce data magnetically, and optical disks reproduce data optically using a laser. Combinations of the above should also be included within the scope of computer-readable media. Although the embodiments disclosed in this disclosure are as described above, the above content is merely an embodiment adopted for understanding the present disclosure and is not intended to limit the present disclosure. Anyone skilled in the art to which this disclosure pertains may make any amendments or changes to the embodiments and details without departing from the spirit and scope of the present disclosure. The patentable scope of the present disclosure is defined by the appended claims.

[0068] This application claims priority to a Chinese patent application bearing application number 202211449384.6 and entitled "Shift Control Method, Vehicle Controller, Vehicle and Storage Medium" filed with the China Patent Office on November 18, 2022, the entire contents of which are hereby incorporated by reference.

Claims

1. 1. A shift control method, comprising: determining a torque exchange time length of a torque exchange phase and a total clutch torque demand T0; Gradually decreasing the shift torque Toff assigned to the clutch to be disengaged and gradually increasing the shift torque Ton assigned to the clutch to be engaged within the torque exchange time length, and satisfying Toff + Ton = T0; Ton and Toff are set to change nonlinearly within the torque exchange time length in order to suppress the influence of changes in the response speed of the torque control system on the smoothness of torque exchange. Shift control method.

2. The torque control system is controlled by a hydraulic system, and the absolute values ​​of the gradients of Ton and Toff are set so as to first go from small to large within the torque exchange time length. The method of claim 1.

3. Gradually decreasing the shift torque Toff assigned to the clutch to be disengaged and gradually increasing the shift torque Ton assigned to the clutch to be engaged within the torque exchange time length Obtaining an initial progress percentage based on a ratio of a currently exchanged time length to the torque exchange time length at set time intervals within the torque exchange time length, correcting the initial progress percentage, and calculating Toff and Ton based on the corrected progress percentage and T0; Within the torque exchange time length, the absolute value of the gradient of the corrected progress percentage first increases from small to large and then decreases from large to small, or first increases from small to large and then remains unchanged. The method of claim 1.

4. Correcting the initial progress percentage includes: adding a current correction value to the initial progress percentage to obtain a corrected progress percentage; The current correction value is calculated based on a trigonometric function that uses the initial progress percentage as an argument. The method of claim 2.

5. The current correction value is calculated by the following formula: X=sin(P0×0.0628)×k X is the current correction value, P0 is the initial progress percentage, and k represents a correction coefficient, which is determined based on the total clutch torque demand. The method of claim 4.

6. Toff and Ton calculated based on the corrected progress percentage and T0 satisfy Ton = T0 × P and Toff = T0 × (100% - P), where P is the corrected progress percentage. The method of claim 3.

7. The method further comprises: Before the torque exchange stage, oil supply control is performed in three stages, and oil is supplied to the engaging clutch using a first hydraulic pressure, a second hydraulic pressure, and a third hydraulic pressure in a first stage, a second stage, and a third stage, respectively; the third hydraulic pressure is equal to a half-engagement point pressure of the clutch to be engaged, and the second hydraulic pressure is greater than the third hydraulic pressure and less than the first hydraulic pressure; The method of claim 1.

8. a difference obtained by subtracting the second hydraulic pressure from the first hydraulic pressure is greater than a difference obtained by subtracting the third hydraulic pressure from the second hydraulic pressure; The method of claim 7.

9. the duration of the first stage is less than the sum of the durations of the second stage and the third stage; 9. The method according to claim 7 or 8.

10. A vehicle controller, a processor and a storage device storing a computer program; When the processor executes the computer program, the processor can realize the shift control method according to any one of claims 1 to 9. Vehicle controller.

11. A vehicle, A vehicle comprising the vehicle controller of claim 10.

12. the vehicle is a hybrid vehicle, and the clutch to be disengaged and the clutch to be engaged are clutches in a hybrid transmission; 12. The vehicle of claim 11.

13. A non-transitory computer-readable storage medium, comprising: The computer-readable storage medium stores a computer program, and the computer program, when executed by a processor, can realize the shift control method according to any one of claims 1 to 9. A non-transitory computer-readable storage medium.

Images