Power split type multi-gear hybrid gearbox acceleration linear control method and system

Abstract

The invention provides a power split type multi-gear hybrid transmission acceleration linear control method and system, and belongs to the technical field of automobile multi-gear hybrid transmissions.The method comprises the steps that transmission gear information, target wheel end torque, engine maximum wheel end driving torque under a target parallel gear and P3 motor end maximum wheel end driving torque are obtained; when the actual gear is the ECVT gear and the target gear is the first direct drive gear or the third direct drive gear, the difference value between the target wheel end torque and the maximum wheel end driving torque of the engine and the difference value between the target wheel end torque and the maximum wheel end driving torque of the P3 motor end under the target parallel gear are calculated; whether the difference value exceeds a first preset torque difference threshold value or not is judged, and when the difference value exceeds the first preset torque difference threshold value, it is confirmed that the P1 motor participates in assistance, and information that the P1 motor participates in assistance is sent out; when the information that the P1 motor participates in assistance is received, the final P1 motor target rotating speed is calculated according to the first preset slope and the original P1 motor target rotating speed, a P1 motor rotating speed control instruction is sent, and the first preset slope is used for controlling the rotating speed of the P1 motor.

Description

Technical Field

[0001] This invention relates to the field of automotive multi-speed hybrid transmission technology, and particularly to a power-split multi-speed hybrid transmission acceleration linear control method and system. Background Technology

[0002] There is now an ECVT power-split multi-speed hybrid transmission. This is an advanced hybrid transmission that is based on the smoothness of an electric car, uses "power split" technology to achieve extreme fuel efficiency, and adds several physical gears to make up for the shortcomings in high-speed and rapid acceleration scenarios.

[0003] This hybrid transmission has multiple gears and operating modes, ranging from ECVT mode to engine direct drive modes such as 1st / 2nd / 3rd / 4th gears. The maximum driving capability differs between ECVT mode and parallel mode. For example, when accelerating at full throttle, ECVT2 switches to 3rd gear in parallel mode, the power suddenly and noticeably increases, giving the driver a distinct sense of abrupt acceleration. Furthermore, when shifting from ECVT2 to 3rd gear in parallel mode, the maximum drive torque at the wheels initially decreases and then increases with vehicle speed. This amplifies the change in maximum drive torque at the wheels before and after the ECVT2 enters 3rd gear, further enhancing the abrupt acceleration sensation.

[0004] Therefore, how to reduce or even eliminate this abrupt acceleration has become a key technical problem that urgently needs to be solved. Summary of the Invention

[0005] The present invention aims to solve at least one of the above-mentioned problems in the prior art and provide a technical solution for switching the ECVT power split mode to the engine direct drive mode (including the initial entry into the direct drive mode) to improve the abrupt acceleration caused by the step change in wheel torque during high throttle acceleration.

[0006] In a first aspect, embodiments of the present invention provide an acceleration linear control method for a power-split multi-speed hybrid transmission, comprising:

[0007] Obtain transmission gear information, target wheel-end torque, maximum engine wheel-end drive torque under target parallel gear, and maximum P3 motor wheel-end drive torque under target parallel gear;

[0008] When the actual gear is ECVT and the target gear is direct drive 1st gear or direct drive 3rd gear, the difference between the target wheel end torque and the maximum wheel end drive torque of the engine and the maximum wheel end drive torque of the P3 motor under the target parallel gear is calculated as the first difference.

[0009] Determine whether the first difference exceeds the first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, confirm that the P1 motor is involved in assist and issue the P1 motor assist information.

[0010] When the P1 motor is received as assist information, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor. Then, a P1 motor speed control command is sent to control the speed of the P1 motor using the first preset slope.

[0011] In a preferred embodiment, when information indicating that motor P1 is participating in assist is received, the final target speed of motor P1 is calculated based on a first preset slope and the original target speed of motor P1, and a speed control command for motor P1 is sent to control the speed of motor P1 using the first preset slope.

[0012] The first preset slope is the descending slope.

[0013] In a preferred embodiment, when information indicating that motor P1 is participating in assist is received, the final target speed of motor P1 is calculated based on a first preset slope and the original target speed of motor P1, and a speed control command for motor P1 is sent to control the speed of motor P1 using the first preset slope.

[0014] The first preset slope includes a first descending slope and a first ascending slope. First, the speed of motor P1 is controlled to decrease according to the first descending slope, and then the speed of motor P1 is controlled to increase according to the first ascending slope.

[0015] In a preferred embodiment, the step of determining whether the first difference exceeds a first preset torque difference threshold, and confirming that the P1 motor participates in assist and issuing P1 motor assist participation information when the first difference exceeds the first preset torque difference threshold includes:

[0016] Hysteresis control is used to determine whether the first difference exceeds the first preset torque difference threshold.

[0017] The first preset torque difference threshold includes: an upper limit for torque difference and a lower limit for torque difference;

[0018] The first difference is continuously calculated;

[0019] When the first difference exceeds the upper limit of the torque difference, it is confirmed that the P1 motor participates in the assist and the P1 motor participates in the assist information is issued. If the new first difference is lower than the lower limit of the torque difference after the P1 motor participates in the assist, it is confirmed that the parallel P1 motor assist limit is exited. The P1 motor participates in the assist information exits after a preset delay.

[0020] In a preferred embodiment, the method further includes: when receiving information that the P1 motor is participating in the power assist, limiting the maximum drive torque of the P1 motor from 0 with a second preset slope, and calculating the total drive torque limit at the P1 end as the sum of the maximum drive torque of the P1 motor after the slope limitation and the current maximum torque of the engine.

[0021] In a preferred embodiment, the method further includes: taking the smaller value between the total driving torque limit at P1 and the original target driving torque at P1 to obtain the final target driving torque at P1.

[0022] In a preferred embodiment, the method further includes: when it is confirmed that the parallel P1 motor assist limit is released when it is confirmed that the P1 motor is not involved in assist, or the actual gear is not in parallel, or the difference between the actual wheel-end transmitted torque and the target wheel-end required torque does not exceed the second preset torque difference threshold, and the maximum drive torque of the P1 motor is no longer limited.

[0023] In a second aspect, embodiments of the present invention provide a power-split multi-speed hybrid transmission acceleration linear control system, the system being configured to implement any of the methods described in the first aspect, the system comprising:

[0024] The acquisition module is used to acquire transmission gear information, target wheel-end torque, maximum engine wheel-end drive torque under the target parallel gear, and maximum P3 motor wheel-end drive torque under the target parallel gear. When the actual gear is ECVT and the target gear is direct drive 1 or direct drive 3, the module calculates the difference between the target wheel-end torque and the maximum engine wheel-end drive torque and the maximum P3 motor wheel-end drive torque under the target parallel gear as the first difference. The module then determines whether the first difference exceeds a first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, the module confirms that the P1 motor is involved in power assist and issues information about the P1 motor's involvement in power assist.

[0025] The control module is used to calculate the final target speed of the P1 motor based on the first preset slope and the original target speed of the P1 motor when it receives the information that the P1 motor is participating in the assist. It then sends a P1 motor control speed command to control the speed of the P1 motor using the first preset slope.

[0026] Thirdly, embodiments of the present invention provide an electronic device, including:

[0027] One or more processors;

[0028] Memory, used to store one or more programs;

[0029] When the one or more programs are executed by the one or more processors, the one or more processors implement any of the methods described in the first aspect.

[0030] Fourthly, embodiments of the present invention provide a computer-readable medium storing a computer program that, when executed by a processor, implements the steps of any of the methods described in the first aspect.

[0031] Beneficial effects of this invention:

[0032] This invention, based on the structural characteristics, principles, and driving capabilities of a multi-speed hybrid transmission integrating ECVT power split mode, addresses the abrupt acceleration issue caused by the initial decrease followed by a step increase in wheel-end drive torque during ECVT parallel mode switching. Firstly, a linear slope control strategy for the target engine and generator speeds during ECVT parallel mode switching is designed to mitigate the rate and extent to which the P1 motor drags down the engine speed during direct drive gear shifts. Secondly, a linear torque limiting control strategy for the P1 motor is designed to limit the torque assist from the P1 motor when the ECVT immediately enters parallel mode during high-throttle acceleration. Combining these control strategies, a smooth increase in wheel-end drive torque during ECVT parallel mode switching and upon entering parallel mode is achieved, resulting in more linear vehicle acceleration, avoiding subjective acceleration sensations for the driver, and significantly improving the overall driving experience. Attached Figure Description

[0033] Figure 1 This is a schematic diagram of an ECVT power-split multi-speed hybrid transmission.

[0034] Figure 2 A schematic diagram of the lever method for shifting gears in ECVT power splitting and direct drive mode.

[0035] Figure 3 This is a schematic diagram showing the change curves of drive torque capability in ECVT mode and 3rd gear parallel mode at different vehicle speeds.

[0036] Figure 4 This diagram illustrates the process of ECVT switching to parallel mode and the system's behavior immediately upon entering parallel mode.

[0037] Figure 5 This is a schematic flowchart of an acceleration linear control method for a power-split multi-speed hybrid transmission provided in an embodiment of the present invention.

[0038] Figure 6 This is a block diagram of the target speed control logic for the ECVT direct drive shifting speed regulation process provided in an embodiment of the present invention.

[0039] Figure 7 This is a schematic diagram illustrating the target engine speed control effect during ECVT direct drive shifting, as provided in an embodiment of the present invention.

[0040] Figure 8 This is a block diagram of the drive torque limiting control logic when entering parallel mode, provided in an embodiment of the present invention.

[0041] Figure 9 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Detailed Implementation

[0042] To enable those skilled in the art to better understand the technical solutions of the present invention, exemplary embodiments of the present invention are described below in conjunction with the accompanying drawings, including various details of the embodiments of the present invention to aid understanding. These should be considered merely exemplary. Therefore, those skilled in the art should recognize that various changes and modifications can be made to the embodiments described herein without departing from the scope and spirit of the present invention. Similarly, for clarity and brevity, descriptions of well-known functions and structures are omitted in the following description.

[0043] Where there is no conflict, the various embodiments of the present invention and the features thereof may be combined with each other.

[0044] As used herein, the term “and / or” includes any and all combinations of one or more related enumerated entries.

[0045] The terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the invention. As used herein, the singular forms “a” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will also be understood that when the terms “comprising” and / or “made of” are used in this specification, the presence of the stated feature, integral, step, operation, element, and / or component is specified, but the presence or addition of one or more other features, integrals, steps, operations, elements, components, and / or groups thereof is not excluded. Terms such as “connected” or “linked” are not limited to physical or mechanical connections but can include electrical connections, whether direct or indirect.

[0046] Unless otherwise specified, all terms used herein (including technical and scientific terms) have the same meaning as commonly understood by one of ordinary skill in the art. It will also be understood that terms such as those defined in commonly used dictionaries should be interpreted as having the meaning consistent with their meaning in the context of the relevant art and the invention, and will not be interpreted as having an idealized or overly formal meaning unless expressly so defined herein.

[0047] In the technical solution of this invention, the collection, storage, use, processing, transmission, provision, and disclosure of user personal information all comply with relevant laws and regulations and do not violate public order and good morals. The use of user data in this technical solution follows relevant national laws and regulations (e.g., the "Information Security Technology - Personal Information Security Specification"). For example: appropriate measures are taken for personal information access control; restrictions are imposed on the display of personal information; the purpose of using personal information does not exceed the scope of direct or reasonable association; and explicit identity targeting is eliminated when using personal information to avoid precisely locating a specific individual.

[0048] The abbreviations and key terms of this invention are defined as follows:

[0049] ECVT stands for Electric Continuously Variable Transmission.

[0050] Figure 1 This is a schematic diagram of an ECVT power-split multi-speed hybrid transmission, which integrates the ECVT power-split mode. Figure 1 As shown, the engine flywheel is connected to the planetary carrier of the single planetary gear set. The P1 generator is coaxially connected to the S2 synchronizer hub and the sun gear. The ring gear is connected to the wheels via the left and right sides of the S1 synchronizer and two sets of gear trains with different speed ratios, through the differential and half-shaft. The P3 drive motor is also connected to the wheels via the differential and half-shaft to another set of gear trains. When the S2 synchronizer is in the middle position and the left / right side of the S1 synchronizer is engaged, two ECVT gears with different speed ratios are formed. The left and right sides of the S1 synchronizer and the left and right sides of the S2 synchronizer can be combined in pairs to achieve four engine direct drive gears. The left side of the S2 synchronizer and the middle of the S1 synchronizer are series gears. When both the S1 and S2 synchronizers are in the middle, it is neutral, i.e., the pure electric EV gear. The shift drum rotates to different positions, controlling the two synchronizers to different positions, corresponding to different gears. The shift drum positions are executed sequentially, as shown in Table 1.

[0051] Table 1

[0052]

[0053] Based on the kinematic characteristics of a single planetary gear set, the engine, P1 generator, and ring gear speeds in ECVT mode satisfy the following relationship: In this configuration, the ring gear speed and wheel speed have a fixed proportional relationship. However, in ECVT mode, the engine speed and wheel speed are not fixed, meaning the engine and wheel speeds are decoupled. Furthermore, based on the dynamic characteristics of a single planetary gear set, the torques acting on the planet carrier, sun gear, and ring gear satisfy the following relationship: =1 : K : (1+K) corresponds to this hybrid transmission. When the ECVT is running stably, if the engine is running, the engine torque is input to the planetary carrier. Engine torque is transferred to P1 generator, and the rest... Engine torque is transmitted to the wheels via the ring gear and gear system, achieving torque splitting; that is, the engine torque is not decoupled from the wheel torque. The lever method can be used to qualitatively analyze the speed-torque relationship of the three components of the planetary gear set, see [link to analysis]. Figure 2As shown, this operating condition is a common ECVT power-split mode. The engine outputs positive torque and positive speed, while the P1 motor outputs negative torque, positive speed, and negative power to generate electricity. The P3 drive motor can drive or generate electricity according to the driver's needs. From ECVT gear to engine direct drive gears (1 / 2 / 3 / 4 gears), i.e., switching from ECVT power-split mode to parallel mode, the S2 synchronizer needs to be engaged from the middle position to the left / right. To avoid power interruption during gear shifting, the engine always outputs drive and charging torque as needed. Based on the gearbox configuration and the operating characteristics of the engine and P1 generator, the P1 generator's speed is adjusted to synchronize with the S2 synchronizer's speed to complete gear engagement. According to the planetary gear set dynamics principle, the planetary gear set is in a balanced state, and the engine torque is always distributed to the P1 generator in a fixed proportion. Simultaneously, the P1 generator outputs the same amount of negative torque to maintain the planetary gear set's balance. To achieve speed regulation of the P1 generator, additional speed-regulating torque is needed to break the existing balance of the planetary gear set, adjusting the P1 generator speed and engine speed to the target direct drive gear speed. See [link to relevant documentation]. Figure 3 As shown. Therefore, in ECVT mode (including the process of switching from ECVT to direct drive mode), the total wheel-end torque is: (engine torque + P1 end inertial torque) * P1 end speed ratio + P3 drive motor torque * P3 end speed ratio. Furthermore, based on the transmission's structural characteristics and parameters, the total wheel-end torque in parallel mode is: (engine + P1 generator) * P1 end speed ratio + P3 drive motor torque * P3 end speed ratio.

[0054] Based on the above analysis of the structure and operating characteristics of multi-speed hybrid transmissions, the maximum driving capacity of ECVT mode and parallel mode is different. For example, the maximum wheel-end driving torque of 1st gear is greater than that of ECVT1 and 3rd gear is greater than that of ECVT1. Figure 3The diagram shows the relationship between the maximum wheel-end drive torque and vehicle speed of ECVT2 and 3 in parallel mode. At 80km / h, the maximum drive torque of 3rd gear is at least 500Nm greater than that of ECVT2. If ECVT2 switches to 3rd gear parallel mode at full throttle acceleration at this time, the wheel-end drive torque will increase by 500Nm, that is, the power suddenly increases significantly, and the driver will have a noticeable abrupt acceleration feeling. Furthermore, during the shift from ECVT2 to parallel 3rd gear, the P1 generator is used for gear shifting and speed adjustment. In ECVT2 mode, the engine speed is relatively high to meet the driver's acceleration needs. However, when shifting into 3rd gear, since engine speed is proportional to vehicle speed, the P1 generator needs to adjust the engine speed to the speed corresponding to the current vehicle speed. Therefore, there is a relatively significant drop in engine speed during the gear shift. Based on the engine's external characteristics, the maximum drive torque also decreases at this time. As the vehicle speed increases during subsequent gear shifts, the engine speed continuously increases, and the maximum drive torque continuously rises. Therefore, from ECVT2 to 3rd gear in parallel, the maximum drive torque at the wheels first decreases and then increases with increasing vehicle speed. This increases the magnitude of the change in maximum drive torque at the wheels before and after the ECVT2 shifts into 3rd gear, further enhancing the abruptness of acceleration. Figure 4 As shown.

[0055] The working principle of this clear distinction lies in:

[0056] 1) Based on the wheel-end torque difference, calculate and identify the working condition that requires activation of the target speed slope control of P1 motor during the ECVT shifting to direct drive gear at high throttle acceleration, and perform linear slope control on the target P1 motor speed under this working condition to avoid the engine speed dropping rapidly and to a relatively low level during the shifting speed adjustment process, which would cause the engine and wheel-end drive torque to become sluggish.

[0057] 2) When entering parallel mode from ECVT mode, the activation and deactivation conditions of P1 motor assist torque limit are identified. After activation, the maximum drive assist torque of P1 motor is limited from 0 with a controllable linear slope, thereby limiting the total drive torque at P1 end. This causes the actual wheel end torque to approach the target, achieving a linear transition of wheel end torque when entering parallel mode, making the vehicle acceleration more linear and avoiding obvious acceleration abruptness.

[0058] Figure 5 This is a flowchart illustrating an acceleration linear control method for a power-split multi-speed hybrid transmission provided in an embodiment of the present invention. Figure 6 This is a block diagram of the target speed control logic for the ECVT direct drive shifting speed regulation process provided in an embodiment of the present invention. Figure 5 and Figure 6 As shown, the method includes:

[0059] Step S1: Obtain the gearbox gear information, target wheel-end torque, maximum wheel-end drive torque of the engine under the target parallel gear, and maximum wheel-end drive torque of the P3 motor under the target parallel gear;

[0060] Step S2: When the actual gear is ECVT and the target gear is direct drive 1 or direct drive 3, calculate the difference between the target wheel end torque and the maximum wheel end drive torque of the engine and the maximum wheel end drive torque of the P3 motor under the target parallel gear as the first difference.

[0061] Step S3: Determine whether the first difference exceeds the first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, confirm that the P1 motor participates in the assist and issue the P1 motor participates in the assist information.

[0062] Step S4: When receiving the information that the P1 motor is participating in the assist, calculate the final target speed of the P1 motor based on the first preset slope and the original target speed of the P1 motor, and send a P1 motor control speed command to control the speed of the P1 motor using the first preset slope.

[0063] Among them, the maximum drive torque capability of direct drive 2nd gear or direct drive 4th gear is not much different from that of the adjacent ECVT gear, and there is no obvious acceleration abruptness. Therefore, there is no need to identify the ECVT switching to 2nd / 4th gear. What needs to be identified is when the actual gear is ECVT gear and the target gear is direct drive 1st gear or direct drive 3rd gear, as a judgment criterion for activating the target speed slope control.

[0064] Considering that the main issue to be addressed is the abrupt acceleration problem after switching from ECVT to direct drive at high throttle, it is only necessary to identify the ECVT switching to direct drive mode at high throttle. Under other operating conditions, there is no need to control the target speed adjustment RPM, otherwise the shift time will be prolonged, which is not conducive to fuel economy. In this system, the torque control strategy prioritizes meeting the driver's torque demands with the engine and P3 drive motor. Only when insufficient are the P1 motors used to output torque to assist the vehicle's acceleration under heavy throttle. Therefore, using the difference between the target wheel-end torque and the maximum wheel-end drive torque of the engine and P3 motor in the target parallel gear position is one of the main criteria for determining whether to activate the target speed slope control during heavy throttle acceleration. There are two reasons for this: First, based on the analysis of the maximum drive torque capability of ECVT and parallel mode, the abrupt acceleration under heavy throttle is mainly due to the participation of the parallel P1 motor in assisting. Therefore, based on the aforementioned wheel-end torque difference, it can be predicted in advance that the P1 motor will participate in assisting when entering parallel mode. Second, if the throttle opening is used directly for identification, because the maximum drive torque capability of the engine and P3 motor varies under different operating conditions and environments, there may be situations where the throttle is very large but the maximum drive torque is small. In this case, the acceleration capability after ECVT switches to direct drive will not be obviously abrupt, and there is no need for target speed slope control.

[0065] When the ECVT switches to direct drive mode and begins shifting speed regulation, the target engine speed decreases in a step manner, controlling the target engine speed to the target speed with a controllable slope. Based on the above-mentioned ECVT shifting speed regulation principle when engaging direct drive, the target engine speed slope control is equivalent to the target P1 motor slope control. Therefore, after the above-mentioned target speed slope control is activated, the target speed of the P1 motor during shifting speed regulation in ECVT direct drive mode is controlled linearly for its rising and falling slopes, where the slope, i.e., the first preset slope mentioned above, is calibrated based on the actual vehicle.

[0066] In some embodiments, the step of switching from ECVT gear to direct drive gear 1 or direct drive gear 3 when the actual gear is ECVT gear and the target gear is direct drive gear 1 or direct drive gear 3 includes: switching from ECVT gear 1 to direct drive gear 1, and switching from ECVT gear 2 to direct drive gear 2.

[0067] In some embodiments, in step S4, when the information indicating that the P1 motor is participating in the assist is received, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor, and a P1 motor control speed command is sent to control the speed of the P1 motor using the first preset slope.

[0068] The first preset slope is the descending slope, so as to control the P1 motor speed to decrease slowly and prevent the target engine speed from dropping abruptly due to a sudden drop in motor speed.

[0069] In some embodiments, in step S4, when the information indicating that the P1 motor is participating in the assist is received, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor, and a P1 motor control speed command is sent to control the speed of the P1 motor using the first preset slope.

[0070] The first preset slope includes a first descending slope and a first ascending slope. First, the speed of motor P1 is controlled to decrease according to the first descending slope, and then the speed of motor P1 is controlled to increase according to the first ascending slope. By controlling the speed of motor P1 to decrease slowly, the problem of a step-like decrease in the target engine speed caused by a sudden drop in motor speed is prevented. By controlling the speed of motor P1 to decrease slowly, the effect of stable speed of motor P1 can be achieved.

[0071] After the above steps, the engine target speed control effect achieved by the embodiment of the present invention during ECVT direct drive shifting is shown in the figure. Figure 7 As shown.

[0072] In some embodiments, step S3, determining whether the first difference exceeds a first preset torque difference threshold, and confirming that the P1 motor participates in assist and issuing P1 motor assist participation information when the first difference exceeds the first preset torque difference threshold, includes the following steps:

[0073] like Figure 6As shown, hysteresis control is used to determine whether the first difference exceeds the first preset torque difference threshold.

[0074] The first preset torque difference threshold includes: an upper limit for torque difference and a lower limit for torque difference;

[0075] The first difference is continuously calculated;

[0076] When the first difference exceeds the upper limit of the torque difference, it is confirmed that the P1 motor participates in the assist and the P1 motor participates in the assist information is issued. If the new first difference is lower than the lower limit of the torque difference after the P1 motor participates in the assist, it is confirmed that the parallel P1 motor assist limit is exited. The P1 motor participates in the assist information exits after a preset delay.

[0077] The torque difference threshold for activation is determined by hysteresis control, and a delay is added after the torque difference condition is activated to exit. This avoids the target speed slope control activation jump, thereby avoiding unstable gear shifting and speed regulation.

[0078] In some embodiments, the method further includes: step S5, when receiving information that the P1 motor participates in assist, limiting the maximum driving torque of the P1 motor from 0 with a second preset slope, and calculating the total driving torque limit at the P1 end as the sum of the maximum driving torque of the P1 motor after the slope limitation and the current maximum torque of the engine.

[0079] In some embodiments, the method further includes: step S6, taking the smaller value between the total drive torque limit at P1 and the original target drive torque at P1 to obtain the final target drive torque at P1.

[0080] In some embodiments, the method further includes: step S7, when it is confirmed that the parallel P1 motor assist limit is exited and the maximum drive torque of the P1 motor is no longer limited when it is confirmed that the P1 motor is not involved in the assist, or the actual gear is not in parallel, or the difference between the actual wheel-end transmitted torque and the target wheel-end required torque does not exceed the second preset torque difference threshold (e.g., 50 Nm, the specific value can be adjusted according to the actual vehicle).

[0081] Figure 8 This is a block diagram of the drive torque limiting control logic when entering parallel mode, provided in an embodiment of the present invention. Figure 8 As shown, the drive torque limiting control logic when entering parallel mode is as follows:

[0082] 1. Enter the parallel P1 motor assist torque limit activation judgment:

[0083] Based on the target speed slope control of the ECVT in direct drive mode, it is determined whether the P1 motor participates in power assistance. When the ECVT enters parallel mode and P1 participates in power assistance, the parallel P1 motor power assistance torque limit control is activated and locked until it is determined that P1 motor power assistance is not needed or the actual gear is no longer parallel, or the actual wheel-end transmitted torque is close to the target wheel-end required torque, that is, the difference between the target and actual wheel-end torque exceeds the threshold (e.g., 50Nm, the specific value can be adjusted according to the actual vehicle). Then, the parallel P1 motor power assistance torque limit control is reset.

[0084] 2. Enter parallel P1 motor assist torque limit control:

[0085] When the parallel P1 motor assist torque limit is activated, the maximum torque used by the P1 motor for driving is limited from 0 with a certain linear slope. The total driving torque limit at the P1 end is the sum of the maximum driving torque of the P1 motor after the slope limit and the current maximum torque of the engine. Otherwise, there is no need to limit the total driving torque at the P1 end.

[0086] 3. Enter parallel P1 terminal drive torque limiting control:

[0087] To address the abrupt acceleration caused by the rapid intervention of the P1 motor's assist torque when the ECVT enters parallel mode under heavy throttle, the final target P1 driving torque is obtained by subtracting the previously limited total driving torque limit from the original target P1 driving torque. Consequently, when entering parallel mode, the wheel torque gradually increases as the P1 motor's assist torque is released at a controllable slope, eliminating the step-like increase in wheel torque. Once the actual wheel torque approaches the target, the P1 motor's assist torque is fully released, thus eliminating the abrupt acceleration felt when entering parallel mode. Furthermore, while maintaining parallel mode, the P1 motor torque is no longer limited to meet acceleration demands.

[0088] Based on the same inventive concept, embodiments of the present invention also provide a power-split multi-speed hybrid transmission acceleration linear control system, the system being configured to implement any of the methods described in the above embodiments, the system comprising:

[0089] The acquisition module is used to acquire transmission gear information, target wheel-end torque, maximum engine wheel-end drive torque under the target parallel gear, and maximum P3 motor wheel-end drive torque under the target parallel gear. When the actual gear is ECVT and the target gear is direct drive 1 or direct drive 3, the module calculates the difference between the target wheel-end torque and the maximum engine wheel-end drive torque and the maximum P3 motor wheel-end drive torque under the target parallel gear as the first difference. The module then determines whether the first difference exceeds a first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, the module confirms that the P1 motor is involved in power assist and issues information about the P1 motor's involvement in power assist.

[0090] The control module is used to calculate the final target speed of the P1 motor based on the first preset slope and the original target speed of the P1 motor when it receives the information that the P1 motor is participating in the assist. It then sends a P1 motor control speed command to control the speed of the P1 motor using the first preset slope.

[0091] Based on the same inventive concept, embodiments of the present invention also provide an electronic device. Figure 9 This is a structural block diagram of an electronic device provided in an embodiment of the present invention. Figure 9 As shown, an embodiment of the present invention provides an electronic device including: one or more processors 101, a memory 102, and one or more I / O interfaces 103. The memory 102 stores one or more programs, which, when executed by the one or more processors, cause the one or more processors to implement any of the methods described in the above embodiments; the one or more I / O interfaces 103 are connected between the processor and the memory, configured to enable information interaction between the processor and the memory.

[0092] The processor 101 is a device with data processing capabilities, including but not limited to a central processing unit (CPU); the memory 102 is a device with data storage capabilities, including but not limited to random access memory (RAM, more specifically SDRAM, DDR, etc.), read-only memory (ROM), electrically erasable programmable read-only memory (EEPROM), and flash memory (FLASH); the I / O interface (read / write interface) 103 is connected between the processor 101 and the memory 102, and can realize information interaction between the processor 101 and the memory 102, including but not limited to a data bus (Bus).

[0093] In some embodiments, the processor 101, memory 102, and I / O interface 103 are interconnected via bus 104, and thus connected to other components of the computing device.

[0094] In some embodiments, the one or more processors 101 include a field-programmable gate array.

[0095] This invention also provides a computer-readable medium. The computer-readable medium stores a computer program, which, when executed by a processor, implements the steps of any of the methods described in the above embodiments. The computer-readable storage medium may be a volatile or non-volatile computer-readable storage medium.

[0096] Those skilled in the art will understand that all or some of the steps, systems, and apparatuses disclosed above, and their functional modules / units, can be implemented as software, firmware, hardware, or suitable combinations thereof. In hardware implementations, the division between functional modules / units mentioned above does not necessarily correspond to the division of physical components; for example, a physical component may have multiple functions, or a function or step may be performed collaboratively by several physical components. Some or all physical components may be implemented as software executed by a processor, such as a central processing unit, digital signal processor, or microprocessor, or as hardware, or as an integrated circuit, such as an application-specific integrated circuit (ASIC). Such software can be distributed on a computer-readable storage medium, which may include computer storage media (or non-transitory media) and communication media (or transient media).

[0097] As is known to those skilled in the art, the term computer storage medium includes volatile and non-volatile, removable and non-removable media implemented in any method or technology for storing information, such as computer-readable program instructions, data structures, program modules, or other data. Computer storage media includes, but is not limited to, random access memory (RAM), read-only memory (ROM), erasable programmable read-only memory (EPROM), static random access memory (SRAM), flash memory or other memory technologies, portable compact disc read-only memory (CD-ROM), digital versatile disc (DVD) or other optical disc storage, magnetic cartridges, magnetic tape, disk storage or other magnetic storage devices, or any other medium that can be used to store desired information and is accessible to a computer. Furthermore, it is known to those skilled in the art that communication media typically contain computer-readable program instructions, data structures, program modules, or other data in modulated data signals such as carrier waves or other transmission mechanisms, and may include any information delivery medium.

[0098] The computer-readable program instructions described herein can be downloaded from computer-readable storage media to various computing / processing devices, or downloaded via a network, such as the Internet, local area network, wide area network, and / or wireless network, to an external computer or external storage device. The network may include copper transmission cables, fiber optic transmission, wireless transmission, routers, firewalls, switches, gateway computers, and / or edge servers. A network adapter card or network interface in each computing / processing device receives the computer-readable program instructions from the network and forwards them to the computer-readable storage media in the respective computing / processing device.

[0099] The computer program instructions used to perform the operations of this invention may be assembly instructions, instruction set architecture (ISA) instructions, machine instructions, machine-dependent instructions, microcode, firmware instructions, state setting data, or source code or object code written in any combination of one or more programming languages, including object-oriented programming languages ​​such as Smalltalk, C++, etc., and conventional procedural programming languages ​​such as the "C" language or similar programming languages. The computer-readable program instructions may be executed entirely on the user's computer, partially on the user's computer, as a standalone software package, partially on the user's computer and partially on a remote computer, or entirely on a remote computer or server. In cases involving a remote computer, the remote computer may be connected to the user's computer via any type of network—including a local area network (LAN) or a wide area network (WAN)—or may be connected to an external computer (e.g., via the Internet using an Internet service provider). In some embodiments, electronic circuitry, such as programmable logic circuitry, field-programmable gate arrays (FPGAs), or programmable logic arrays (PLAs), is personalized by utilizing state information from the computer-readable program instructions. This electronic circuitry can execute the computer-readable program instructions to implement various aspects of the invention.

[0100] The computer program product described herein can be implemented specifically through hardware, software, or a combination thereof. In one alternative embodiment, the computer program product is specifically embodied in a computer storage medium; in another alternative embodiment, the computer program product is specifically embodied in a software product, such as a software development kit (SDK), etc.

[0101] Various aspects of the present invention are described herein with reference to flowchart illustrations and / or block diagrams of methods, apparatus (systems), and computer program products according to embodiments of the invention. It should be understood that each block of the flowchart illustrations and / or block diagrams, and combinations of blocks in the flowchart illustrations and / or block diagrams, can be implemented by computer-readable program instructions.

[0102] These computer-readable program instructions can be provided to a processor of a general-purpose computer, a special-purpose computer, or other programmable data processing apparatus to produce a machine such that, when executed by the processor of the computer or other programmable data processing apparatus, they create means for implementing the functions / actions specified in one or more blocks of the flowchart and / or block diagram. These computer-readable program instructions can also be stored in a computer-readable storage medium that causes a computer, programmable data processing apparatus, and / or other device to operate in a particular manner; thus, the computer-readable medium storing the instructions comprises an article of manufacture that includes instructions for implementing aspects of the functions / actions specified in one or more blocks of the flowchart and / or block diagram.

[0103] Computer-readable program instructions may also be loaded onto a computer, other programmable data processing apparatus, or other device to cause a series of operational steps to be performed on the computer, other programmable data processing apparatus, or other device to produce a computer-implemented process, thereby causing the instructions executed on the computer, other programmable data processing apparatus, or other device to perform the functions / actions specified in one or more boxes of a flowchart and / or block diagram.

[0104] The flowcharts and block diagrams in the accompanying drawings illustrate the architecture, functionality, and operation of possible implementations of systems, methods, and computer program products according to various embodiments of the present invention. In this regard, each block in a flowchart or block diagram may represent a module, segment, or portion of an instruction, which contains one or more executable instructions for implementing a specified logical function. In some alternative implementations, the functions marked in the blocks may occur in a different order than those shown in the drawings. For example, two consecutive blocks may actually be executed substantially in parallel, and they may sometimes be executed in reverse order, depending on the functions involved. It should also be noted that each block in the block diagrams and / or flowcharts, and combinations of blocks in the block diagrams and / or flowcharts, may be implemented using a dedicated hardware-based system that performs the specified function or action, or using a combination of dedicated hardware and computer instructions.

[0105] Example embodiments have been disclosed herein, and while specific terminology has been used, it is for illustrative purposes only and should be construed as such, and is not intended to be limiting. In some instances, it will be apparent to those skilled in the art that features, characteristics, and / or elements described in conjunction with particular embodiments may be used alone, or in combination with features, characteristics, and / or elements described in conjunction with other embodiments, unless otherwise expressly indicated. Therefore, those skilled in the art will understand that various changes in form and detail may be made without departing from the scope of the invention as set forth in the appended claims.

Claims

1. A method for linear acceleration control of a power-split multi-speed hybrid transmission, characterized in that, include: Obtain the gearbox gear information, target wheel-end torque, maximum wheel-end drive torque of the engine under the target parallel gear, and maximum wheel-end drive torque of the P3 motor under the target parallel gear; When the actual gear is ECVT and the target gear is direct drive 1st gear or direct drive 3rd gear, the difference between the target wheel end torque and the maximum wheel end drive torque of the engine and the maximum wheel end drive torque of the P3 motor under the target parallel gear is calculated as the first difference. Determine whether the first difference exceeds the first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, confirm that the P1 motor is involved in assist and issue the P1 motor assist information. When the P1 motor is received as assist information, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor. Then, a P1 motor speed control command is sent to control the speed of the P1 motor using the first preset slope.

2. The method according to claim 1, characterized in that, When the P1 motor is received as assist information, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor. A P1 motor control speed command is then sent to control the P1 motor speed using the first preset slope. (This is part of the following steps.) The first preset slope is the descending slope.

3. The method according to claim 1, characterized in that, When the P1 motor is received as assist information, the final target speed of the P1 motor is calculated based on the first preset slope and the original target speed of the P1 motor. A P1 motor control speed command is then sent to control the P1 motor speed using the first preset slope. (This is part of the following steps.) The first preset slope includes a first descending slope and a first ascending slope. First, the speed of motor P1 is controlled to decrease according to the first descending slope, and then the speed of motor P1 is controlled to increase according to the first ascending slope.

4. The method according to claim 1, characterized in that, The step of determining whether the first difference exceeds the first preset torque difference threshold, and confirming that the P1 motor participates in assist and issuing P1 motor assist participation information when the first difference exceeds the first preset torque difference threshold includes: Hysteresis control is used to determine whether the first difference exceeds the first preset torque difference threshold. The first preset torque difference threshold includes: an upper limit for torque difference and a lower limit for torque difference; The first difference is continuously calculated; When the first difference exceeds the upper limit of the torque difference, it is confirmed that the P1 motor participates in the assist and the P1 motor participates in the assist information is issued. If the new first difference is lower than the lower limit of the torque difference after the P1 motor participates in the assist, it is confirmed that the parallel P1 motor assist limit is exited. The P1 motor participates in the assist information exits after a preset delay.

5. The method according to claim 1, characterized in that, Also includes: When the P1 motor is received to participate in the assist, the maximum driving torque of the P1 motor is limited from 0 with the second preset slope. The total driving torque limit of the P1 end is calculated to be the sum of the maximum driving torque of the P1 motor after the slope limit and the current maximum torque of the engine.

6. The method according to claim 5, characterized in that, Also includes: The final target P1 driving torque is obtained by taking the smaller value between the total driving torque limit at P1 and the original target P1 driving torque.

7. The method according to claim 6, characterized in that, Also includes: When it is confirmed that the P1 motor is not participating in the assist, or the actual gear is not in parallel, or the difference between the actual wheel-end transmitted torque and the target wheel-end required torque does not exceed the second preset torque difference threshold, the parallel P1 motor assist restriction is confirmed to be off, and the maximum drive torque of the P1 motor is no longer restricted.

8. A power-split multi-speed hybrid transmission acceleration linear control system, characterized in that, The system is configured to implement the method as described in any one of claims 1 to 7, the system comprising: The acquisition module is used to acquire transmission gear information, target wheel-end torque, maximum engine wheel-end drive torque under the target parallel gear, and maximum P3 motor wheel-end drive torque under the target parallel gear. When the actual gear is ECVT and the target gear is direct drive 1 or direct drive 3, the module calculates the difference between the target wheel-end torque and the maximum engine wheel-end drive torque and the maximum P3 motor wheel-end drive torque under the target parallel gear as the first difference. The module then determines whether the first difference exceeds a first preset torque difference threshold. If the first difference exceeds the first preset torque difference threshold, the module confirms that the P1 motor is involved in power assist and issues information about the P1 motor's involvement in power assist. The control module is used to calculate the final target speed of the P1 motor based on the first preset slope and the original target speed of the P1 motor when it receives the information that the P1 motor is participating in the assist. It then sends a P1 motor control speed command to control the speed of the P1 motor using the first preset slope.

9. An electronic device, characterized in that, include: One or more processors; Memory, used to store one or more programs; When the one or more programs are executed by the one or more processors, the one or more processors implement the method as described in any one of claims 1 to 7.

10. A computer-readable medium having a computer program stored thereon, characterized in that, When the computer program is executed by a processor, it implements the steps of the method as described in any one of claims 1 to 7.

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