Hybrid vehicle and its coasting upshift control method, device and storage medium

Abstract

The present disclosure relates to a hybrid vehicle and a coasting upshift control method, device and storage medium thereof, wherein the hybrid vehicle includes an engine and a front drive motor for providing power to the front axle, and the control method includes: determining whether the hybrid vehicle is in a coasting upshift state; when the hybrid vehicle is in a coasting upshift state, obtaining the charging torque required by the front drive motor; when the charging torque required by the front drive motor is greater than or equal to a first threshold, controlling the engine to increase the output torque. In this way, during the coasting upshift process of the hybrid vehicle, when the charging torque required by the front drive motor is greater than or equal to the first threshold, that is, the charging torque demand is large, the engine can be controlled to increase the output torque, that is, the engine can be controlled to gradually increase the torque to ensure the charging demand of the front drive motor, so that the front axle torque can be reasonably distributed, reducing the vehicle jerking, thereby ensuring the stability of the front axle torque and the torque stability of the entire vehicle during the shifting process.

Description

Technical Field

[0001] The present disclosure relates to the technical field of hybrid vehicles, and in particular, to a coasting upshift control method for a hybrid vehicle, a coasting upshift control device for a hybrid vehicle, a hybrid vehicle, and a computer-readable storage medium. Background Art

[0002] The vehicle torque of a P2+P4 architecture hybrid vehicle is composed of the front axle torque and the rear axle torque. During the coasting upshift process, the vehicle torque is a negative value, that is, the coasting energy recovery torque. At the same time, in this process, most of the vehicle torque is preferentially allocated to the rear axle, and the remaining part is allocated to the front axle, and the torque allocated to the front axle needs to ensure the speed control of the TCU (Transmission Control Unit). Therefore, there will be a situation where the front axle motor charging torque demand is large. The existing P2+P4 architecture hybrid vehicle control strategy does not consider the distribution of engine torque when the front axle motor charging torque is large or small during the coasting upshift process. Therefore, the front axle and the whole vehicle will be shaken due to improper torque scheduling and distribution and unreasonable front axle torque distribution when the clutch is engaged. During the coasting upshift process, the whole vehicle will suddenly reduce a lot of torque. Summary of the invention

[0003] The purpose of the present disclosure is to provide a hybrid vehicle and a coasting upshift control method, device and storage medium thereof, so that the torque of the front axle engine and motor can be reasonably distributed during the coasting upshift process to ensure the stability of the front axle torque and the smoothness of the vehicle torque.

[0004] In order to achieve the above object, the present disclosure provides a coasting upshift control method for a hybrid vehicle, wherein the hybrid vehicle includes an engine and a front drive motor for providing power to a front axle, and the control method includes:

[0005] determining whether the hybrid vehicle is in a coasting upshift state;

[0006] When the hybrid vehicle is in a coasting upshift state, obtaining a charging torque required by the front drive motor;

[0007] When the charging torque required by the front drive motor is greater than or equal to a first threshold, the engine is controlled to increase the output torque.

[0008] Optionally, the step of determining whether the hybrid vehicle is in a coasting upshift state comprises:

[0009] Acquiring a pedal state and a current vehicle speed of the hybrid vehicle;

[0010] When the pedal of the hybrid vehicle is not depressed and the current vehicle speed is greater than or equal to a speed threshold, it is determined that the hybrid vehicle is in a coasting upshift state.

[0011] Optionally, the hybrid vehicle includes a battery for powering the front-drive motor, and the step of obtaining the charging torque required for the front-drive motor includes: obtaining the charge of the battery, and when the charge is less than or equal to a charge threshold, determining the charging torque required for the front-drive motor based on the charge of the battery.

[0012] Optionally, a first clutch is arranged between the engine and the front-drive motor, the front axle also includes a gearbox connected to the front-drive motor, and a second clutch is arranged between the front-drive motor and the gearbox; the control method includes: during the gear shifting process, controlling the second clutch to switch between a slipping state and a closed state.

[0013] Optionally, the second clutch is a dual clutch.

[0014] Optionally, the control method further includes:

[0015] When the charging torque required by the front drive motor is less than a first threshold, the output torque of the engine is controlled to satisfy the friction torque.

[0016] Optionally, the hybrid vehicle further includes a rear-drive motor, and the hybrid vehicle has a P2+P4 architecture power configuration.

[0017] According to a second aspect of the present disclosure, a coasting upshift control device for a hybrid vehicle is provided, the hybrid vehicle comprising an engine and a front drive motor for providing power to a front axle, the control device comprising:

[0018] A determination module, used to determine whether the hybrid vehicle is in a coasting upshift state;

[0019] an acquisition module, configured to acquire the charging torque required by the front drive motor when the hybrid vehicle is in a coasting upshift state; and

[0020] The control module is used to control the engine to increase the output torque when the charging torque required by the front drive motor is greater than or equal to a first threshold.

[0021] According to a third aspect of the present disclosure, a hybrid vehicle is provided, comprising the coasting upshift control device for the hybrid vehicle as described above.

[0022] According to a fourth aspect of the present disclosure, there is provided a computer-readable storage medium having a computer program stored thereon, wherein the program implements the steps of the control method described above when executed by a processor.

[0023] Through the above technical scheme, during the gliding upshift process of the hybrid vehicle, when the charging torque required by the front drive motor is greater than or equal to the first threshold, that is, the charging torque demand is large, the engine can be controlled to increase the output torque, that is, the engine can be controlled to gradually increase the torque to ensure the charging demand of the front drive motor, so that the front axle torque can be reasonably distributed and the vehicle jerking can be reduced, thereby ensuring the stability of the front axle torque and the torque stability of the entire vehicle during the gear shifting process, and at the same time, the vehicle torque can respond to the driver's request in a timely manner during the upshift process.

[0024] Other features and advantages of the present disclosure will be described in detail in the following detailed description. BRIEF DESCRIPTION OF THE DRAWINGS

[0025] The accompanying drawings are used to provide a further understanding of the present disclosure and constitute a part of the specification. Together with the following specific embodiments, they are used to explain the present disclosure but do not constitute a limitation of the present disclosure. In the accompanying drawings:

[0026] Figure 1 is a control logic diagram of a coasting upshift control method for a hybrid vehicle provided by an exemplary embodiment of the present disclosure;

[0027] Figure 2 is a control logic diagram of a coasting upshift control method for a hybrid vehicle provided by another exemplary embodiment of the present disclosure;

[0028] Figure 3 is a block diagram of a coasting upshift control device for a hybrid vehicle provided by an exemplary embodiment of the present disclosure;

[0029] Figure 4 is a block diagram of a hybrid vehicle provided by an exemplary embodiment of the present disclosure. DETAILED DESCRIPTION

[0030] The specific implementation of the present disclosure is described in detail below in conjunction with the accompanying drawings. It should be understood that the specific implementation described herein is only used to illustrate and explain the present disclosure, and is not used to limit the present disclosure.

[0031] In the present disclosure, unless otherwise stated, the directional words used, such as "inside", "outside", refer to the inside and outside of the corresponding component profile. In addition, the terms "first", "second", etc. used in the present disclosure are to distinguish one element from another element and do not have order and importance.

[0032] Reference Figure 1The embodiment of the present disclosure provides a coasting upshift control method for a hybrid vehicle, which is used to control the distribution of the front axle torque (i.e., the engine torque and the motor torque) during the coasting upshift process of the hybrid vehicle. The hybrid vehicle may include an engine and a front drive motor for providing power to the front axle, that is, the front axle may be jointly powered by the engine and the front drive motor. The control method may include the following steps:

[0033] S101, determining whether the hybrid vehicle is in a coasting upshift state;

[0034] S102, when the hybrid vehicle is in a coasting upshift state, obtaining a charging torque required by the front drive motor;

[0035] S103, determining whether the charging torque required by the front drive motor is greater than or equal to a first threshold;

[0036] S104, when the charging torque required by the front drive motor is greater than or equal to a first threshold, controlling the engine to increase the output torque.

[0037] Referring to the description in the background technology, the coasting energy recovery torque during the coasting upshift process, in the control method provided in the embodiment of the present disclosure, when the charging torque demand of the front drive motor is large, for example, greater than or equal to the first threshold, the engine will gradually increase the torque to ensure charging. That is, as the front drive motor outputs more charging (negative torque), in order to ensure the stability of the vehicle torque, the engine needs to output a larger positive torque at this time to ensure the stability of the front axle torque and the stability of the vehicle torque during the gear shifting process. The control method can be implemented by the control of the HCU (Hybrid Control Unit, hybrid vehicle controller). In addition, controlling the engine to increase the output torque can be reflected in the control of the engine output power increase.

[0038] It should be noted that during the process of the hybrid vehicle coasting upshift, when the charging torque required by the front-drive motor is low, the torque allocated to the front axle by the coasting energy recovery torque can meet the required charging torque; when the charging torque required by the front-drive motor is large, that is, it reaches the first threshold or even exceeds the first threshold, the torque allocated to the front axle by the coasting energy recovery torque is insufficient to meet the charging torque required by the front-drive motor. At this time, the engine output torque is needed to supply the front-drive motor to supplement the required charging torque. It is understandable that the engine changes with the front-drive motor. If the front-drive motor charging torque is large, the engine needs to output a larger torque to ensure that the front axle torque is constant or has a smaller deviation from the previous moment, that is, the charging torque of the front-drive motor can be used to adjust the engine output torque, thereby ensuring the stability of the entire vehicle.

[0039] Through the above technical scheme, during the gliding upshift process of the hybrid vehicle, when the charging torque required by the front drive motor is greater than or equal to the first threshold, that is, the charging torque demand is large, the engine can be controlled to increase the output torque, that is, the engine can be controlled to gradually increase the torque to ensure the charging demand of the front drive motor, so that the front axle torque can be reasonably distributed and the vehicle jerking can be reduced, thereby ensuring the stability of the front axle torque and the torque stability of the entire vehicle during the gear shifting process, and at the same time, the vehicle torque can respond to the driver's request in a timely manner during the upshift process.

[0040] According to some embodiments, reference Figure 2 The above step of determining whether the hybrid vehicle is in a coasting upshift state may include:

[0041] S1011, obtaining a pedal state of the hybrid vehicle to determine whether the pedal is in a stepped state;

[0042] S1012, obtaining the current vehicle speed of the hybrid vehicle, and determining whether the current vehicle speed is greater than or equal to a speed threshold.

[0043] That is, the hybrid vehicle's pedal state information and current vehicle speed information can be used to determine whether the hybrid vehicle is in a coasting upshift state. In other words, the pedal state information and current vehicle speed information can be used as the criteria for determining whether the hybrid vehicle is in a coasting upshift state. Figure 2 When the hybrid vehicle's pedal is not stepped on and the current vehicle speed is greater than or equal to the speed threshold, it can be determined that the hybrid vehicle is in a coasting upshift state. That is, when the hybrid vehicle's pedal is not stepped on and the current vehicle speed is greater than or equal to the speed threshold, it can be determined that the hybrid vehicle is in a coasting upshift state, and the next step S102 can be performed, that is, obtaining the charging torque required by the front drive motor.

[0044] It should be noted that the "pedal" in "pedal is not stepped on" may include the accelerator pedal (i.e., gas pedal) and the brake pedal. Correspondingly, "pedal is not stepped on" may mean that the accelerator pedal is completely released and the brake pedal is not stepped on, i.e., both pedals are in the released state at this time.

[0045] Here, as an implementation, the speed threshold may be 50km / h-80km / h. That is, the hybrid vehicle may have a higher vehicle speed to ensure sufficient sliding energy. For example, the pedal may be released when the vehicle speed reaches about 60km / h.

[0046] According to some embodiments, a hybrid vehicle may include a battery for powering a front-drive motor, so as to provide power to the front-drive motor through the battery. The step of obtaining the charging torque required for the front-drive motor may include obtaining the power of the battery, so as to determine the charging torque required for the front-drive motor through the obtained power of the battery. That is, the charging torque required for the front-drive motor can be obtained through the power of the battery, that is, the power of the battery can be used as a preliminary judgment condition for the large charging torque demand of the front-drive motor. In this way, the HCU of the hybrid vehicle can compare the determined charging torque with the first threshold value, so as to control whether the engine needs to increase the output torque.

[0047] In order to reduce the number of comparisons of the HCU internal strategy, the battery power can be further used as a criterion for determining the size of the charging torque requirement. That is, when the battery power is greater than the power threshold, the charging torque required by the front drive motor is relatively small, and the torque allocated to the front axle by the coasting energy recovery torque can meet the charging torque required by the front drive motor. At this time, the HCU internal strategy can not determine the charging torque by the battery power and compare the charging torque with the first threshold; when the battery power is less than or equal to the power threshold, the charging torque required by the front drive motor is relatively large. At this time, the HCU of the hybrid vehicle can calculate the charging torque required by the front drive motor according to the current battery power, thereby obtaining the charging torque required by the front drive motor, and compare the obtained charging torque with the first threshold, so as to control whether the engine needs to increase the output torque. In addition, for the entire coasting upshift process, while satisfying the stability of the front axle torque, the charging torque of the front drive motor is required to meet the consumption of the accessories at the minimum, and the rest can be recovered to the battery, so that there is a certain input power when the next driver requests a drive, to ensure the drive.

[0048] Here, as an implementation, the power threshold may be 10%-13% of the battery capacity. The power threshold, the speed threshold and the first threshold may be set accordingly according to actual conditions, and the present disclosure does not limit this.

[0049] In the embodiments provided in the present disclosure, the charging torque required by the front-drive motor may be between 0 and 120 N·m, which are all within the capacity range of the engine, that is, the engine can meet the maximum charging torque required by the front-drive motor. Among them, the first threshold value may be 55 N·m-65 N·m. For example, when the charging torque required by the front-drive motor is about 60 N·m, it is necessary to control the output torque of the engine to gradually increase to ensure that the front-drive motor has sufficient charging torque.

[0050] According to some embodiments, a first clutch may be provided between the engine and the front drive motor, the front axle may further include a gearbox connected to the front drive motor, and a second clutch may be provided between the front drive motor and the gearbox. That is, the front axle of the hybrid vehicle may be composed of an engine, a first clutch, a front drive motor, a second clutch and a gearbox, and the engine, the first clutch, the front drive motor, the second clutch and the gearbox may be connected in sequence. Among them, the control method may include, during the shifting process, controlling the second clutch to switch between a slipping state and a closed state. The slipping state may be understood as the clutch being in a semi-linked state, and the closed state may be understood as the clutch being in a fully linked state. When the second clutch is in a slipping state, there is a speed difference between the power input end and the power output end, the friction between the pressure plate and the friction plate is less than that in the fully linked state, the pressure plate and the friction plate on the flywheel are in a sliding friction state, and the power transmitted from the flywheel by the engine output shaft is partially transmitted to the gearbox. When the hybrid vehicle is at a high speed during coasting upshift, when the accelerator pedal is completely released, the vehicle moves forward by its own inertia. At this time, the target gear is high, the actual gear rises toward the target gear, the transmission ratio becomes smaller, and the second clutch state switches between closed and slipping until the actual gear rises to the target gear, so that the TCU responds to normal shifting without TCU intervention. By switching the second clutch between the slipping state and the closed state, the problem of jerking during the shifting process can be effectively prevented. During the coasting upshift process, the first clutch can be in a closed state.

[0051] Among them, when the HCU detects that the TCU target gear is equal to the actual gear, if there is no driving request at this time, the second clutch can be controlled to enter the closed state, the vehicle torque is output stably, and the front and rear axle torque is distributed according to the ratio. After the gear shift is completed, the charging torque of a certain gear is output stably according to demand.

[0052] As an implementation method, the second clutch may be a dual clutch. The dual clutch has fast gear shifting, fuel saving, high comfort, and can improve the smoothness of the gear shifting process and reduce the vehicle's sense of frustration.

[0053] According to some embodiments, the control method provided by the present disclosure may further include: when the charging torque required by the front drive motor is less than a first threshold, controlling the output torque of the engine to meet the friction torque. That is, when the charging torque required by the front drive motor is low, the engine only needs to meet the friction torque generated by the friction existing in the engine cylinder itself.

[0054] According to the embodiment provided by the present disclosure, the hybrid vehicle may further include a rear-drive motor, that is, the rear axle may be composed of a rear-drive motor and a gearbox, and the rear-drive motor may output power. As an implementation, the hybrid vehicle may have a P2+P4 architecture power configuration.

[0055] Reference Figure 3 The embodiment of the present disclosure further provides a coasting upshift control device 100 for a hybrid vehicle, comprising: a judgment module 11 , an acquisition module 12 and a control module 13 .

[0056] Among them, the judgment module 11 can be used to judge whether the hybrid vehicle is in a coasting upshift state; the acquisition module 12 can be used to obtain the charging torque required by the front drive motor when the hybrid vehicle is in a coasting upshift state; the control module 13 can be used to control the engine to increase the output torque when the charging torque required by the front drive motor is greater than or equal to a first threshold.

[0057] Therefore, during the gliding and shifting process of the hybrid vehicle, when the charging torque required by the front drive motor is greater than or equal to the first threshold, that is, the charging torque demand is large, the control device can control the engine to increase the output torque, that is, control the engine to gradually increase the torque to ensure the charging demand of the front drive motor, so that the front axle torque can be reasonably distributed and the vehicle jerking can be reduced, thereby ensuring the stability of the front axle torque and the torque stability of the entire vehicle during the shifting process, and at the same time, the vehicle torque can respond to the driver's request in time during the shifting process.

[0058] Furthermore, the judgment module 11 may also be used to judge whether the charging torque required by the front drive motor is greater than or equal to a first threshold.

[0059] Furthermore, the acquisition module 12 can also be used to acquire the pedal state and current vehicle speed of the hybrid vehicle.

[0060] Furthermore, in the case where the hybrid vehicle includes a battery for powering the front drive motor, the acquisition module 12 can also be used to obtain the battery power, and the corresponding judgment module 11 can also be used to judge whether the battery power is less than or equal to the power threshold.

[0061] Furthermore, when a first clutch is provided between the engine and the front-drive motor, the front axle includes a gearbox connected to the front-drive motor, and a second clutch is provided between the front-drive motor and the gearbox, the control module 13 can also be used to control the second clutch to switch between a slipping state and a closed state during gear shifting.

[0062] Furthermore, the control module 13 may also be configured to control the output torque of the engine to satisfy the friction torque when the charging torque required by the front-drive motor is less than a first threshold.

[0063] It should be noted that the above explanation of the embodiment of the coasting upshift control method for a hybrid vehicle is also applicable to the coasting upshift control device for a hybrid vehicle of the present embodiment, and will not be repeated here.

[0064] Reference Figure 4The embodiment of the present disclosure further provides a hybrid vehicle 200, comprising the above-mentioned coasting upshift control device 100 for the hybrid vehicle, so as to implement the above-mentioned coasting upshift control method for the hybrid vehicle.

[0065] The embodiment of the present disclosure also provides a computer-readable storage medium including program instructions, and when the program is executed by a processor, the steps of the coasting upshift control method of the hybrid vehicle can be implemented. For example, the computer-readable storage medium can be a memory including program instructions, and the program instructions can be executed by a processor of an electronic device to complete the coasting upshift control method of the hybrid vehicle.

[0066] The preferred embodiments of the present disclosure are described in detail above in conjunction with the accompanying drawings; however, the present disclosure is not limited to the specific details in the above embodiments. Within the technical concept of the present disclosure, a variety of simple modifications can be made to the technical solution of the present disclosure, and these simple modifications all fall within the protection scope of the present disclosure.

[0067] It should also be noted that the various specific technical features described in the above specific embodiments can be combined in any suitable manner without contradiction. In order to avoid unnecessary repetition, the present disclosure will not further describe various possible combinations.

[0068] In addition, various embodiments of the present disclosure may be arbitrarily combined, and as long as they do not violate the concept of the present disclosure, they should also be regarded as the contents disclosed by the present disclosure.

Claims

1. A method for controlling a coasting upshift of a hybrid vehicle, the hybrid vehicle comprising an engine and a front drive motor for providing power to a front axle, characterized in that: The control method comprises: determining whether the hybrid vehicle is in a coasting upshift state; When the hybrid vehicle is in a coasting upshift state, obtaining a charging torque required by the front drive motor; When the charging torque required by the front drive motor is greater than or equal to a first threshold, the engine is controlled to increase the output torque.

2. The control method according to claim 1, characterized in that: The step of determining whether the hybrid vehicle is in a coasting upshift state comprises: Acquiring a pedal state and a current vehicle speed of the hybrid vehicle; When the pedal of the hybrid vehicle is not stepped on, the current vehicle speed is greater than or equal to a speed threshold, and the actual gear position rises toward the target gear position, it is determined that the hybrid vehicle is in a coasting upshift state.

3. The control method according to claim 1, characterized in that: The hybrid vehicle includes a battery for supplying power to the front motor, and the step of obtaining the charging torque required by the front motor includes: The power level of the battery is obtained, and when the power level is less than or equal to a power threshold, the charging torque required by the front drive motor is determined according to the power level of the battery.

4. The control method according to claim 1, characterized in that: A first clutch is provided between the engine and the front drive motor, the front axle further comprises a gearbox connected to the front drive motor, and a second clutch is provided between the front drive motor and the gearbox; The control method comprises: during a gear shifting process, controlling the second clutch to switch between a slipping state and a closed state.

5. The control method according to claim 4, characterized in that: The second clutch is a dual clutch.

6. The control method according to claim 1, characterized in that: The control method further comprises: When the charging torque required by the front drive motor is less than a first threshold, the output torque of the engine is controlled to satisfy the friction torque.

7. The control method according to any one of claims 1 to 6, characterized in that: The hybrid vehicle also includes a rear-drive motor, and the hybrid vehicle has a P2+P4 architecture power configuration.

8. A coasting upshift control device for a hybrid vehicle, the hybrid vehicle comprising an engine and a front drive motor for providing power to a front axle, characterized in that: The control device comprises: A determination module, used to determine whether the hybrid vehicle is in a coasting upshift state; an acquisition module, configured to acquire the charging torque required by the front drive motor when the hybrid vehicle is in a coasting upshift state; and The control module is used to control the engine to increase the output torque when the charging torque required by the front drive motor is greater than or equal to a first threshold.

9. A hybrid vehicle, characterized in that: The invention comprises the coasting upshift control device for a hybrid vehicle according to claim 8.

10. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the program is executed by a processor, the steps of the control method according to any one of claims 1 to 7 are implemented.

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