Shift control method for an automatic manual transmission vehicle

Abstract

The present invention relates to a shift control method for an automatic manual transmission vehicle. A shift control method for an automatic manual transmission (AMT) of a vehicle includes, when a shift operation is started, increasing torque of a second motor while reducing torque of a first motor so that output torque variation of an output shaft due to the torque of the first motor is minimized. According to the shift control method, the torque of the second motor, which is increased when the transmission is released, speed synchronized, and engaged, is kept constant. After the control of the transmission engagement is completed, the torque of the second motor is controlled so that the output torque of the output shaft follows a predetermined target torque while the torque of the first motor is controlled to be increased.

Description

Technical Field

[0001] This invention generally relates to a shift control method for vehicles, and more specifically, to a shift control technology for vehicles equipped with an automatic manual transmission (AMT). Background Technology

[0002] The statements in this section are provided only as background information in relation to the present invention and do not constitute prior art.

[0003] Although AMT uses the same shifting mechanism as a typical manual transmission, AMT allows clutch operation and gear shifting to be performed automatically by separate clutch actuators and shift actuators, thereby improving driver convenience.

[0004] However, it has been found that because the shifting operation of an AMT is automatically performed by the actuator according to the driving situation, unlike the manual shifting operation performed according to the driver's intention, torque interruption basically accompanies the shifting process, which can cause uncomfortable shifting feeling and lead to a decrease in the vehicle's power performance.

[0005] The foregoing is intended only to help understand the background technology of the present invention and is not intended to imply that the present invention falls within the scope of related technologies known to those skilled in the art. Summary of the Invention

[0006] This invention proposes a shift control method for AMT vehicles (i.e., vehicles equipped with AMT). Specifically, this method can suppress or prevent torque interruption during AMT shifting to provide a superior shifting feel and prevent a decline in the power performance of AMT vehicles, thereby improving the marketability of AMT vehicles.

[0007] In one aspect of the invention, a shift control method for an automated manual transmission (AMT) for a vehicle is provided. The AMT includes a first motor, a second motor, and a planetary gear unit. The first motor powers a first rotating element of the planetary gear unit, and the second motor powers either the first or second rotating element of the planetary gear unit. The second rotating element is connected to an output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method may include: when a shift operation begins, increasing the torque of the second motor while decreasing the torque of the first motor, thereby minimizing the change in output torque of the output shaft caused by the change in torque of the first motor; maintaining a constant torque increase from the second motor during transmission release, speed synchronization, and transmission engagement control; and after transmission engagement control is completed, controlling the torque of the second motor while controlling the increase in torque of the first motor, such that the output torque of the output shaft follows a predetermined target torque.

[0008] The output torque of the output shaft can be kept constant from the previous steps by following the target torque.

[0009] The target torque followed by the output torque of the output shaft can be a gradually increasing target torque in the later stages.

[0010] According to another aspect of the invention, a shift control method for an automated manual transmission (AMT) is provided, the AMT including a first motor, a second motor, and a planetary gear unit, wherein the first motor provides power to a first rotating element of the planetary gear unit, the second motor provides power to either the first or second rotating element of the planetary gear unit, the second rotating element is coupled to an output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method may include: when a shift operation begins, increasing the torque of the second motor while decreasing the torque of the first motor, such that the output torque of the output shaft follows a predetermined pre-increased target torque; maintaining a constant torque increase from the second motor during transmission release, speed synchronization, and transmission engagement control; and after transmission release control is completed, controlling the torque of the second motor while controlling the increase of the torque of the first motor, such that the output torque of the output shaft follows a predetermined target torque.

[0011] The output torque of the output shaft can be kept constant from the previous steps by following the target torque.

[0012] The target torque followed by the output torque of the output shaft can be a gradually increasing target torque in the later stages.

[0013] The target torque to be increased in the early stage can be set to be greater than or equal to the maximum torque of the second motor.

[0014] The target torque for later increases can be set to be greater than or equal to the maximum torque of the second motor.

[0015] Even if the target torque is increased later and is set to be greater than the maximum torque of the second motor, the second motor can still be controlled by the maximum torque of the second motor.

[0016] According to another aspect of the present invention, a shift control method for an automated manual transmission (AMT) is provided, the AMT including a first motor, a second motor, and a planetary gear unit, wherein the first motor provides power to a first rotating element of the planetary gear unit, the second motor provides power to either the first or second rotating element of the planetary gear unit, the second rotating element is coupled to an output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method may include: when a shift operation begins, increasing the torque of the first motor while decreasing the torque of the second motor, such that the output torque variation of the output shaft caused by the torque variation of the second motor is minimized; maintaining a constant torque increase from the first motor during transmission release, speed synchronization, and transmission engagement control; and after transmission release control is completed, controlling the torque of the first motor while controlling the increase of the torque of the second motor, such that the output torque of the output shaft follows a predetermined target torque.

[0017] The output torque of the output shaft can be kept constant from the previous steps by following the target torque.

[0018] The target torque followed by the output torque of the output shaft can be a gradually increasing target torque in the later stages.

[0019] According to another aspect of the present invention, a shift control method for an automated manual transmission (AMT) is provided, the AMT including a first motor, a second motor, and a planetary gear unit, wherein the first motor provides power to a first rotating element of the planetary gear unit, the second motor provides power to either the first or second rotating element of the planetary gear unit, the second rotating element is coupled to an output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method may include: when a shift operation begins, increasing the torque of the first motor while decreasing the torque of the second motor, such that the output torque of the output shaft follows a predetermined target torque that has been increased previously; maintaining a constant torque increase in the first motor during transmission release, speed synchronization, and transmission engagement control; and after transmission release control is completed, controlling the torque of the first motor while controlling the increase in the torque of the second motor, such that the output torque of the output shaft follows a predetermined target torque.

[0020] The output torque of the output shaft can be kept constant from the previous steps by following the target torque.

[0021] The target torque followed by the output torque of the output shaft can be a gradually increasing target torque in the later stages.

[0022] The shift control method for AMT vehicles according to the present invention can suppress or prevent torque interruption during the shifting process of AMT vehicles, so as to provide a good shifting feel and prevent the power performance of AMT vehicles from deteriorating, thereby improving the marketability of AMT vehicles.

[0023] In addition, during gear shifting, the output torque of the output shaft can remain constant or increase, thereby achieving excellent acceleration response and maximizing the vehicle's power performance.

[0024] Other applications will become apparent from the description provided herein. It should be understood that the specification and specific examples are for illustrative purposes only and are not intended to limit the scope of the invention. Attached Figure Description

[0025] To provide a good understanding of the invention, various embodiments of the invention will now be described by way of example with reference to the accompanying drawings, in which:

[0026] Figure 1 A schematic diagram illustrating the structure of an AMT to which the present invention can be applied;

[0027] Figure 2 To show Figure 1 A diagram showing the operating modes of AMT;

[0028] Figure 3 A flowchart illustrating a shift control method for an AMT according to a first embodiment of the present invention is provided.

[0029] Figure 4 A schematic diagram illustrating a shift control method for an AMT according to a first embodiment of the present invention;

[0030] Figure 5 A flowchart illustrating a shift control method for an AMT according to a second embodiment of the present invention is provided.

[0031] Figure 6 A schematic diagram illustrating a shift control method for an AMT according to a second embodiment of the present invention;

[0032] Figure 7 A flowchart illustrating a shift control method for an AMT according to a third embodiment of the present invention is provided.

[0033] Figure 8 A schematic diagram illustrating a shift control method for an AMT according to a third embodiment of the present invention;

[0034] Figure 9 A flowchart illustrating a shift control method for an AMT according to a fourth embodiment of the present invention is provided.

[0035] Figure 10 A schematic diagram illustrating a shift control method for an AMT according to a fourth embodiment of the present invention;

[0036] Figure 11 A schematic diagram illustrating a shift control method for an AMT according to a fifth embodiment of the present invention;

[0037] Figure 12 A schematic diagram illustrating a shift control method for an AMT according to a sixth embodiment of the present invention;

[0038] Figure 13 A schematic diagram illustrating a shift control method for an AMT according to a seventh embodiment of the present invention is provided.

[0039] The accompanying drawings described herein are for illustrative purposes only and are not intended to limit the scope of the invention in any way. Detailed Implementation

[0040] The following description is merely exemplary in nature and is not intended to limit the invention, application, or use. It should be understood that in all the drawings, corresponding reference numerals denote the same or corresponding parts and features.

[0041] Figure 1 The schematic diagram illustrates the structure of an AMT to which the present invention can be applied, wherein two power sources are connected to the AMT. Here, the two power sources are a first motor MG1 and a second motor MG2.

[0042] The AMT is configured such that it can supply power from the first motor MG1 to the planetary gear unit PG by changing the transmission ratio, and change the path of supplying power from the second motor MG2 to the planetary gear unit PG, thereby outputting power to the output shaft OUT connected to the planetary gear unit PG.

[0043] The first planetary gear unit PG includes a first rotating element, a second rotating element, and a third rotating element. Figure 1 In the diagram, the first rotating element corresponds to the sun gear S, the second rotating element corresponds to the planet carrier C, and the third rotating element corresponds to the internal gear ring R.

[0044] In other words, the planetary gear unit PG includes a sun gear S, a planet carrier C, and an internal ring gear R. The first motor MG1 is configured to provide power to the sun gear S by changing the gear ratio using a first transmission unit. The second motor MG2 is configured to change the path of power delivery to either the planet carrier C or the sun gear using a second transmission unit. The internal ring gear R is configured to move between a position where it is directly connected to the planet carrier C via a third transmission unit S3 and a position where it is fixed to the transmission housing CS.

[0045] The output shaft OUT is directly connected to the planetary carrier C, the output gear OG is integrally mounted on the output shaft OUT, and the intermediate shaft MS is mounted on the sun gear S.

[0046] A first motor MG1 is connected to a first input shaft IN1. A first driving gear D1 and a second driving gear D2 are rotatably connected to the first input shaft IN1. A first driven gear P1 meshing with the first driving gear D1 and a second driven gear P2 meshing with the second driving gear D2 are mounted on an intermediate shaft MS. A first synchronization unit S1, capable of directly connecting either the first driving gear D1 or the second driving gear D2 to the first input shaft IN1, is mounted on the first input shaft IN1.

[0047] Here, the first synchronization unit S1, the first driving gear D1, the second driving gear D2, the first driven gear P1, and the second driven gear P2 constitute the first transmission unit.

[0048] The second motor MG2 is connected to the second input shaft IN2. The third drive gear D3 and the fourth drive gear D4 are rotatably arranged on the second input shaft IN2. The third driven gear P3, meshing with the third drive gear D3, and the fourth driven gear P4, meshing with the fourth drive gear D4, are mounted on the intermediate shaft MS. A second synchronization unit S2, capable of directly connecting either the third drive gear D3 or the fourth drive gear D4 to the second input shaft IN2, is mounted on the second input shaft IN2.

[0049] Here, the second synchronization unit S2, the third driving gear D3, the fourth driving gear D4, the third driven gear P3, and the fourth driven gear P4 constitute the second transmission unit.

[0050] The third transmission unit S3 is configured such that it can slide in the axial direction of the intermediate shaft MS, thereby directly connecting the internal gear ring R to the planet carrier C or the transmission housing CS.

[0051] Each of the first synchronization unit S1 of the first transmission unit, the second synchronization unit S2 of the second transmission unit, and the third transmission unit S3 is operated by a corresponding shift actuator. Such shift actuators are controlled by a controller that receives information such as vehicle speed and accelerator pedal displacement.

[0052] In addition, the controller can be configured to control the torque and speed of the first motor MG1 and the second motor MG2.

[0053] refer to Figure 2 The AMT is configured to enable the AMT to achieve six shift positions, namely the first shift position to the sixth shift position, based on the working states of the first synchronization unit S1, the second synchronization unit S2 and the third transmission unit S3.

[0054] refer to Figures 3 to 6 According to the first and second embodiments of the present invention, the shift control method for an AMT for a vehicle includes: step S11, that is, when the shift operation begins, while decreasing the torque of the first motor MG1, increasing the torque of the second motor MG2, so as to minimize the change in output torque of the output shaft OUT caused by the change in torque of the first motor MG1; step S12, that is, when performing control on the transmission release, speed synchronization and transmission engagement, keeping the increased torque of the second motor MG2 constant; and the following step, that is, after the control on transmission engagement is completed, when controlling the increase in torque of the first motor MG1, controlling the torque of the second motor MG2, so that the output torque of the output shaft OUT follows a predetermined target torque.

[0055] In the first embodiment, the target torque followed by the output torque of the output shaft OUT remains a constant value continuously from the previous steps. Conversely, in the second embodiment, the target torque followed by the output torque of the output shaft OUT is a gradually increasing, predetermined, later-increased target torque.

[0056] In other words, the first implementation scheme is configured to minimize the change in output torque of the output shaft OUT caused by the change in torque of the first motor MG1.

[0057] Therefore, the first solution includes step S13, which is to increase the torque of the first motor MG1 while decreasing the torque of the second motor MG2, so as to keep the output torque of the output shaft OUT constant, as described above.

[0058] For example, when shifting to 1st or 2nd gear while the driver has already pressed the accelerator pedal, the shifting operation can consist of a total of seven (7) steps, such as... Figure 4 As shown.

[0059] The first shift position is such that the first drive gear D1 is directly connected to the first input shaft IN1 through the first synchronization unit S1, the fourth drive gear D4 is directly connected to the second input shaft IN2 through the second synchronization unit S2, and the internal gear ring R is fixed to the transmission housing CS through the third transmission unit S3.

[0060] In order to shift from the first shift position to the second shift position, it is desirable for the first synchronization unit S1 to release the first drive gear D1 from the first input shaft IN1 and to directly connect the second drive gear D2 to the first input shaft IN1.

[0061] In step 1, the shift operation begins in response to the generation of a shift command indicating a shift from the first shift position to the second shift position.

[0062] In step 2, the following coordinated control is performed: when the torque of the first motor MG1 is reduced, the torque of the second motor MG2 is increased to suppress or compensate for the reduction in torque output via the output shaft OUT in response to the torque change of the first motor MG1, so that the first synchronization unit S1 releases the first drive gear D1 from the first input shaft IN1.

[0063] In step 3, when the torque of the first motor MG1 is sufficiently reduced, the first synchronization unit S1 releases the first drive gear D1 from the first input shaft IN1.

[0064] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0065] In step 4, when the first drive gear D1 is released from the first input shaft IN1 and is in neutral, the speed of the first motor MG1 is reduced so that the speed of the second drive gear D2 is synchronized with the speed of the first input shaft IN1.

[0066] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0067] In step 5, when the speed of the first input shaft IN1 is synchronized with the speed of the second drive gear D2, the second drive gear D2 is directly connected to the first input shaft IN1 through the first synchronization unit S1.

[0068] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0069] In step 6, when the connection between the second drive gear D2 and the first input shaft IN1 is completed, the following coordinated control is executed: when the torque of the first motor MG1 is increased, the torque of the second motor MG2 is decreased, so that the output torque change caused by the change in torque of the first motor MG1 is reduced or minimized.

[0070] In step 7, it can be understood that the shift from the first shift position to the second shift position is completed due to the control of the torque of the first motor MG1 and the torque of the second motor MG2 in step 6.

[0071] Therefore, it can be assumed that the actual gear shifting operation is performed through steps 2 to 6. Figure 4 As shown, during gear shifting, the output torque of the output shaft OUT can remain constant.

[0072] Therefore, this shift control method can obtain reliable and constant output torque by eliminating the torque interruption that occurs during shifting operations in related technologies, thereby improving the shifting feel and thus enhancing the marketability of the vehicle.

[0073] For reference, the operations of "transmission release", "speed synchronization" and "transmission engagement" mentioned above correspond to steps 3, 4 and 5, respectively.

[0074] refer to Figure 5 and Figure 6 According to a second embodiment of the present invention, the shift control method for an AMT (Automated Manual Transmission) for a vehicle includes: step S21, that is, when the shift operation begins, while decreasing the torque of the first motor MG1, increasing the torque of the second motor MG2, so that the output torque change of the output shaft OUT caused by the torque change of the first motor MG1 is reduced or minimized; step S22, that is, when performing control on the transmission release, speed synchronization and transmission engagement, keeping the increased torque of the second motor MG2 constant; and step S23, that is, after the control of transmission engagement is completed, when controlling the increase of the torque of the first motor MG1, controlling the torque of the second motor MG2, so that the output torque of the output shaft OUT follows the predetermined target torque to be increased later.

[0075] For example, a 2-1 downshift performed while the driver has already pressed the accelerator pedal can be described as consisting of a total of 7 steps, such as... Figure 6 As shown.

[0076] In step 1, the shift operation begins in response to the generation of a shift command indicating a shift from the second shift position to the first shift position.

[0077] In step 2, the following coordinated control is performed: when the torque of the first motor MG1 is reduced, the torque of the second motor MG2 is increased to prevent or compensate for the reduction in torque output via the output shaft OUT in response to the torque change of the first motor MG1, so that the first synchronization unit S1 releases the second drive gear D2 from the first input shaft IN1.

[0078] In step 3, when the torque of the first motor MG1 is sufficiently reduced, the first synchronization unit S1 releases the second drive gear D2 from the first input shaft IN1.

[0079] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0080] In step 4, when the second drive gear D2 is released from the first input shaft IN1 and is in neutral, the speed of the first motor MG1 is increased so that the speed of the first drive gear D1 is synchronized with the speed of the first input shaft IN1.

[0081] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0082] In step 5, when the speed of the first input shaft IN1 is synchronized with the speed of the first drive gear D1, the first drive gear D1 is directly connected to the first input shaft IN1 through the first synchronization unit S1.

[0083] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0084] In step 6, when the connection between the first drive gear D1 and the first input shaft IN1 is completed, the following coordinated control is executed: the torque of the first motor MG1 is increased, and the torque of the second motor MG2 is increased at the same time, so that the output torque of the output shaft OUT follows the target torque that is increased later.

[0085] In this embodiment, unlike the first embodiment, the output torque is increased to follow the target torque that increases later, rather than keeping the output torque constant, thereby further improving the feeling of vehicle acceleration.

[0086] Therefore, based on the characteristics of the corresponding vehicle model, through multiple experiments and analyses, the target torque to be increased later can be pre-designed and set to an appropriate value so as to increase the target torque to be increased in proportion to the displacement of the accelerator pedal moved by the driver, the operation acceleration, etc.

[0087] In step 7, it can be understood that the shift from the second shift position to the first shift position is completed due to the control of the torque of the first motor MG1 and the torque of the second motor MG2 in step 6.

[0088] According to this implementation scheme, the output torque of the output shaft OUT remains constant without torque interruption during vehicle downshifting, but increases in the final stage of the shift operation. Therefore, the shifting feel of the vehicle can be improved, and a sense of acceleration can be obtained, thereby significantly improving the vehicle's power performance.

[0089] refer to Figures 7 to 10 According to the third and fourth embodiments of the present invention, the shift control method for an AMT (Automated Manual Transmission) in a vehicle includes: step S31, that is, when the shift operation begins, while decreasing the torque of the first motor MG1, increasing the torque of the second motor MG2, so that the output torque of the output shaft OUT follows a predetermined target torque that has been increased in the early stage; step S32, that is, when performing control on the transmission release, speed synchronization, and transmission engagement, keeping the increased torque of the second motor MG2 constant; and the following step, that is, after the control on transmission engagement is completed, when controlling the increase of the torque of the first motor MG1, controlling the torque of the second motor MG2, so that the output torque of the output shaft OUT follows a predetermined target torque. The target torque that has been increased in the early stage refers to the torque value that has increased in the early stage.

[0090] In the third embodiment, the target torque followed by the output torque of the output shaft OUT remains a constant value continuously from the previous steps. Conversely, in the fourth embodiment, the target torque followed by the output torque of the output shaft OUT is a gradually increasing, predetermined, later-increased target torque.

[0091] In other words, the third implementation scheme is configured to reduce or minimize the change in output torque of the output shaft OUT caused by the change in torque of the first motor MG1.

[0092] Therefore, the third solution includes step S33, which is to reduce the torque of the second motor MG2 while increasing the torque of the first motor MG1, so as to keep the output torque of the output shaft OUT at a constant value, as described above.

[0093] For example, a 2-1 downshift performed while the driver has already pressed the accelerator pedal can be described as consisting of a total of seven (7) steps, such as Figure 8 As shown.

[0094] In step 1, the shift operation begins in response to the generation of a shift command indicating a shift from the second shift position to the first shift position.

[0095] In step 2, the following coordinated control is performed: while reducing the torque of the first motor MG1, the torque of the second motor MG2 is increased, so that the output torque of the output shaft OUT follows the previously increased target torque, so that the first synchronization unit S1 releases the second drive gear D2 from the first input shaft IN1.

[0096] In this embodiment, unlike the first embodiment, the output torque is increased to follow the previously increased target torque, rather than remaining constant, thereby further improving the feeling of vehicle acceleration.

[0097] Therefore, based on the characteristics of the corresponding vehicle model, through multiple experiments and analyses, the target torque to be increased in the early stage can be pre-designed and set to an appropriate value so as to increase the target torque in the early stage in proportion to the displacement of the accelerator pedal moved by the driver, the operation acceleration, etc.

[0098] In step 3, when the torque of the first motor MG1 is sufficiently reduced, the first synchronization unit S1 releases the second drive gear D2 from the first input shaft IN1.

[0099] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0100] In step 4, when the second drive gear D2 is released from the first input shaft IN1 and is in neutral, the speed of the first motor MG1 is increased so that the speed of the first drive gear D1 is synchronized with the speed of the first input shaft IN1.

[0101] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0102] In step 5, when the speed of the first input shaft IN1 is synchronized with the speed of the first drive gear D1, the first drive gear D1 is directly connected to the first input shaft IN1 through the first synchronization unit S1.

[0103] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0104] In step 6, when the connection between the first drive gear D1 and the first input shaft IN1 is completed, the following cooperative operation is performed: when the torque of the first motor MG1 is increased, the torque of the second motor MG2 is decreased, so that the output torque change caused by the change in torque of the first motor MG1 is reduced or minimized.

[0105] In step 7, it can be understood that the shift from the second shift position to the first shift position is completed due to the control of the torque of the first motor MG1 and the torque of the second motor MG2 in step 6.

[0106] According to the present invention, during the downshifting process of the vehicle, the output torque of the output shaft OUT increases in the early stage of the shift operation and then remains constant without torque interruption until the shift operation is completed. Therefore, the shifting feel of the vehicle can be improved, and a sense of acceleration can be obtained, thereby significantly improving the vehicle's power performance.

[0107] refer to Figure 9 and Figure 10 According to a fourth embodiment of the present invention, the shift control method for an AMT (Automated Manual Transmission) for a vehicle includes: step S41, that is, when the shift operation begins, while decreasing the torque of the first motor MG1, increasing the torque of the second motor MG2, such that the output torque of the output shaft OUT follows a predetermined target torque that increases in the early stage; step S32, that is, when performing control on the transmission release, speed synchronization and transmission engagement, keeping the increased torque of the second motor MG2 constant; and step S43, that is, after the control on transmission engagement is completed, while controlling the increase of the torque of the first motor MG1, controlling the torque of the second motor MG2, such that the output torque of the output shaft OUT follows a predetermined target torque that increases in the later stage.

[0108] For example, a 2-1 downshift performed while the driver has already pressed the accelerator pedal can be described as consisting of a total of 7 steps, such as... Figure 10 As shown.

[0109] Here, only steps 2 and 6 of the above 7 steps will be described, because the other steps are the same as those in the first to third implementation schemes.

[0110] The difference between this implementation scheme and the first to third implementation schemes is that, in steps 2 and 6, the output torque of the output shaft OUT is controlled to follow the target torque that increases in the early stage and the target torque that increases in the later stage.

[0111] Therefore, the output torque is controlled to follow the target torque that increases in the early stage before the first synchronization unit S1 is in neutral, and to follow the target torque that increases in the later stage after the first synchronization unit S1 is in neutral. This allows the vehicle to accelerate in the early and late stages of the shift operation, and keeps the output torque constant without torque interruption. Therefore, the shifting feel of the vehicle can be improved, and the feeling of acceleration can be obtained, thus significantly improving the vehicle's power performance.

[0112] The target torque to be increased in the early stage can be set to be greater than or equal to the maximum torque of the second motor MG2.

[0113] In this situation, the second motor MG2 can be controlled to generate torque close to its maximum torque, which further helps to improve the feeling of vehicle acceleration.

[0114] exist Figure 10 As shown in step 6, when the torque of the first motor MG1 increases to the target torque that follows the subsequent increase, the torque of the first motor MG1 can be slightly reduced. This indicates that the torque of the second motor MG2 can be controlled to remain constant or decrease based on the magnitude of the target torque that follows the increase and the increment of the torque of the first motor MG1.

[0115] In other words, Figure 10 In step 2, when the torque of the second motor MG2 increases to its maximum torque, since the target torque increase in the early stage is set to be greater than or equal to the maximum torque of the second motor MG2, the maximum torque of the second motor MG2 is maintained during steps 3 to 5. In step 6, the torque of the second motor MG2 is slightly reduced according to the magnitude of the target torque increase in the later stage and the torque of the first motor MG1, and the output torque of the output shaft OUT follows the target torque that increases with the delay.

[0116] The target torque for later increases can be set to be greater than or equal to the maximum torque of the second motor MG2.

[0117] In other words, Figure 11 The fifth embodiment shown is essentially the same as the fourth embodiment, except that in step 6 the target torque for the later increase is set to be greater than or equal to the maximum torque of the second motor MG2. Therefore, the second motor MG2 is controlled so that the torque of the second motor MG2 increases to the maximum torque in step 2 and remains the same even after step 6.

[0118] Even if the target torque is increased later and is set to be greater than the maximum torque of the second motor MG2, the second motor MG2 can be controlled by the maximum torque of the second motor MG2, thereby obtaining the durability of the second motor MG2 and the maximum acceleration performance of the vehicle.

[0119] As described above Figure 1 The transmission shown illustrates the 1-2 upshift and 2-1 downshift operations. The 2-3, 4-5, and 5-6 upshift operations can also be performed in essentially the same manner as the 1-2 upshift operation. Similarly, the 6-5, 5-4, and 3-2 downshift operations can be performed in essentially the same manner as the 2-1 downshift operation.

[0120] Reference Figure 12 The remaining 3-4 gear shifting operations are described.

[0121] In the third shift position, the second drive gear D2 is directly connected to the first input shaft IN1 through the first synchronization unit S1, the third drive gear D3 is directly connected to the second input shaft IN2 through the second synchronization unit S2, and the internal gear ring R is fixed to the transmission housing CS through the third transmission unit S3.

[0122] exist Figure 12 In the diagram, the 3-4 gear shifting operation is shown to consist of steps 1 to 7.

[0123] In step 1, in response to the generation of an upshift command indicating an upshift to the fourth shift position, the shift operation begins.

[0124] In step 2, the following coordinated control is performed: when the torque of the first motor MG1 is reduced, the torque of the second motor MG2 is increased to prevent or compensate for the reduction in torque output via the output shaft OUT in response to the torque change of the first motor MG1, so that the first synchronization unit S1 releases the first drive gear D1 from the first input shaft IN1.

[0125] In step 3, when the reduction of the torque of the first motor MG1 is completed, and the torque level of the second motor MG2, which was finally increased in step 2, is kept at a level that reduces or minimizes the change in output torque, the first synchronization unit S1 releases the second drive gear D2 from the first input shaft IN1, and the third transmission unit S3 releases the internal gear ring R from the transmission housing CS.

[0126] In step 4, while the torque level of the second motor MG2 remains the same as that of the second motor MG2 in step 3, the third transmission unit S3 directly connects the internal gear ring R to the planet C, and the speed of the first motor MG1 is reduced to synchronize the speed of the second drive gear D2 with the speed of the first input shaft IN1, so as to reduce or minimize the output torque variation of the output shaft OUT.

[0127] In step 5, when the speed of the first input shaft IN1 is synchronized with the speed of the second drive gear D2, the first synchronization unit S1 directly connects the second drive gear D2 to the first input shaft IN1.

[0128] Here, the torque of the second motor MG2 remains constant, thus the output torque of the output shaft OUT remains constant.

[0129] In step 6, when the connection between the second drive gear D2 and the first input shaft IN1 is completed, the following coordinated control is executed: when the torque of the first motor MG1 is increased, the torque of the second motor MG2 is decreased, so that the output torque change caused by the change in torque of the first motor MG1 is reduced or minimized.

[0130] In step 7, it can be understood that the shift to the fourth shift position is completed due to the control of the torque of the first motor MG1 and the torque of the second motor MG2 in step 6.

[0131] at last, Figure 13 The power-on 4-3 downshifting operation, consisting of steps 1 to 7, is shown.

[0132] In step 1, in response to the generation of a downshift command indicating a downshift to the third shift position, the shift operation begins.

[0133] In step 2, the following coordinated control is performed: while reducing the torque of the first motor MG1, the torque of the second motor MG2 is increased, so that the output torque of the output shaft OUT follows the previously increased target torque, so that the first synchronization unit S1 releases the first drive gear D1 from the first input shaft IN1.

[0134] Here, the torque of the second motor MG2 can be increased to the maximum torque of the second motor MG2.

[0135] In step 3, when the torque of the first motor MG1 is sufficiently reduced, the second motor MG2 maintains the torque at the level that was finally increased in step 2, so that the output torque change is reduced or minimized. The first synchronization unit S1 releases the first drive gear D1 from the first input shaft IN1, and the third transmission unit S3 releases the internal gear ring R from the planet carrier C that is already directly connected to the internal gear ring R.

[0136] In step 4, when the first drive gear D1 is released from the first input shaft IN1 and the internal gear ring R is released from the planet carrier C, the third transmission unit S3 fixes the internal gear ring R to the transmission housing CS and increases the speed of the first motor MG1, so that when the torque level of the second motor MG2 remains constant after step 3, the speed of the second drive gear D2 and the speed of the first input shaft IN1 can be synchronized, so that the output torque variation of the output shaft OUT is reduced or minimized.

[0137] In step 5, when the speed of the second drive gear D2 is synchronized with the speed of the first input shaft IN1, while the torque level of the second motor MG2 remains constant after step 4, the first synchronization unit S1 connects the second drive gear D2 to the first input shaft IN1 to reduce or minimize the output torque variation.

[0138] In step 6, when the connection between the second drive gear D2 and the first input shaft IN1 is completed, the torque of the first motor MG1 is increased, and the torque of the second motor MG2 is controlled so that the output torque of the output shaft OUT follows the target torque that is increased later. Figure 13 In the middle, the torque of the second motor MG2 is slightly reduced.

[0139] In step 7, it can be understood that the shift to the third shift position is completed due to the control of the torque of the first motor MG1 and the torque of the second motor MG2 in step 6.

[0140] In addition to interchangeably functioning the first motor MG1 and the second motor MG2, a shift control method similar to the first and second embodiments can also be provided. A shift control method for an AMT (Automated Manual Transmission) for a vehicle according to an eighth embodiment of the present invention is also provided. The AMT includes a first motor MG1, a second motor MG2, and a planetary gear unit PG, wherein the first motor MG1 can provide power to a first rotating element of the planetary gear unit PG, the second motor MG2 can provide power to either the first or second rotating element of the planetary gear unit PG, the second rotating element is connected to an output shaft OUT, and the power output from the first motor MG1 and the power output from the second motor MG2 are combined via the planetary gear unit PG.

[0141] The shift control method may include the following steps: when the shift operation begins, while decreasing the torque of the second motor MG2, increasing the torque of the first motor MG1, so that the output torque change of the output shaft OUT caused by the torque change of the second motor MG2 is reduced or minimized; the following steps: when controlling the release, speed synchronization and engagement of the transmission, keeping the increased torque of the first motor MG1 constant; and the following steps: after the control of the transmission engagement is completed, controlling the torque of the first motor MG1, so that when the torque of the second motor MG2 is increased, the output torque of the output shaft OUT follows a predetermined target torque.

[0142] Here, the target torque followed by the output torque of the output shaft OUT can be continuously maintained as a constant value from the previous steps.

[0143] Furthermore, the target torque followed by the output torque of the output shaft OUT can be a gradually increasing, predetermined target torque that increases later.

[0144] In addition to interchangeably functioning the first motor MG1 and the second motor MG2, a shift control method similar to the third and fourth embodiments can also be provided. A shift control method for an AMT (Automated Manual Transmission) for a vehicle according to a ninth embodiment of the present invention is also provided. The AMT includes a first motor MG1, a second motor MG2, and a planetary gear unit PG, wherein the first motor MG1 can provide power to a first rotating element of the planetary gear unit PG, the second motor MG2 can provide power to either the first or second rotating element of the planetary gear unit PG, the second rotating element is connected to an output shaft OUT, and the power output from the first motor MG1 and the power output from the second motor MG2 are combined via the planetary gear unit PG.

[0145] The shift control method may include the following steps: when the shift operation begins, while decreasing the torque of the second motor MG2, increasing the torque of the first motor MG1, so that the output torque of the output shaft OUT follows a predetermined target torque that has been increased previously; the following steps: when controlling the release, speed synchronization, and engagement of the transmission, keeping the increased torque of the first motor MG1 constant; and the following steps: after the control of the transmission engagement is completed, controlling the torque of the first motor MG1, so that when the torque of the second motor MG2 is increased, the output torque of the output shaft OUT follows a predetermined target torque.

[0146] Here, the target torque followed by the output torque of the output shaft OUT can be continuously maintained as a constant value from the previous steps.

[0147] Furthermore, the target torque followed by the output torque of the output shaft OUT can be a gradually increasing, predetermined target torque that increases later.

[0148] Although specific embodiments of the invention have been described for illustrative purposes, those skilled in the art will understand that various modifications, additions, and deletions are possible without departing from the scope and spirit of the invention.

Claims

1. A shift control method for an automatic-manual transmission, the automatic-manual transmission comprising a first motor, a second motor, and a planetary gear unit, wherein, The first motor provides power to the first rotating element of the planetary gear unit, and the second motor provides power to either the first or second rotating element of the planetary gear unit. The second rotating element is connected to the output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method includes: In response to the shifting operation, when the torque supplied from the first motor to the first rotating element of the planetary gear unit is reduced, the torque supplied from the second motor to the first or second rotating element of the planetary gear unit is increased, so that the output torque change of the output shaft caused by the change in torque supplied from the first motor to the first rotating element of the planetary gear unit is minimized. When controlling the release, speed synchronization and transmission engagement of the transmission, the increased torque supplied from the second motor to the first or second rotating element of the planetary gear unit is kept constant; After the control of the gearbox engagement is completed, when the torque supplied from the first motor to the first rotating element of the planetary gear unit is increased, the torque supplied from the second motor to the first or second rotating element of the planetary gear unit is controlled so that the output torque of the output shaft follows the predetermined target torque.

2. The shift control method for an automatic-manual transmission according to claim 1, wherein, The predetermined target torque remains constant.

3. The shift control method for an automatic-manual transmission according to claim 1, wherein, The predetermined target torque is a target torque that gradually increases in the later stages.

4. A shift control method for an automatic-manual transmission, the automatic-manual transmission comprising a first motor, a second motor, and a planetary gear unit, wherein, The first motor provides power to the first rotating element of the planetary gear unit, and the second motor provides power to either the first or second rotating element of the planetary gear unit. The second rotating element is connected to the output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method includes: In response to the shifting operation, when the torque supplied from the first motor to the first rotating element of the planetary gear unit is reduced, the torque supplied from the second motor to the first or second rotating element of the planetary gear unit is increased, so that the output torque of the output shaft follows the predetermined target torque that has been increased in the previous period. When controlling the release, speed synchronization and transmission engagement of the transmission, the increased torque supplied from the second motor to the first or second rotating element of the planetary gear unit is kept constant; After the control of the transmission release is completed, when the torque supplied from the first motor to the first rotating element of the planetary gear unit is increased, the torque supplied from the second motor to the first or second rotating element of the planetary gear unit is controlled so that the output torque of the output shaft follows the predetermined target torque.

5. The shift control method for an automatic-manual transmission according to claim 4, wherein, The predetermined target torque remains constant.

6. The shift control method for an automatic-manual transmission according to claim 4, wherein, The predetermined target torque is a target torque that gradually increases in the later stages.

7. The shift control method for an automatic-manual transmission according to claim 6, wherein, The predetermined target torque for the initial increase is set to be greater than or equal to the maximum torque supplied from the second motor to the first or second rotating element of the planetary gear unit.

8. The shift control method for an automatic-manual transmission according to claim 6, wherein, The target torque for the later increase is set to be greater than or equal to the maximum torque provided from the second motor to the first or second rotating element of the planetary gear unit.

9. The shift control method for an automatic-manual transmission according to claim 8, wherein, Even if the target torque is increased later and set to be greater than the maximum torque provided from the second motor to the first or second rotating element of the planetary gear unit, the second motor is controlled by the maximum torque of the second motor.

10. A shift control method for an automatic manual transmission, the automatic manual transmission comprising a first motor, a second motor, and a planetary gear unit, wherein, The first motor provides power to the first rotating element of the planetary gear unit, and the second motor provides power to either the first or second rotating element of the planetary gear unit. The second rotating element is connected to the output shaft, and the power output from the first motor and the power output from the second motor are combined via the planetary gear unit. The shift control method includes: In response to the shifting operation, when the torque supplied from the second motor to the first rotating element or the second rotating element of the planetary gear unit is reduced, the torque supplied from the first motor to the first rotating element of the planetary gear unit is increased, so that the output torque change of the output shaft caused by the change in the torque supplied from the second motor to the first rotating element or the second rotating element of the planetary gear unit is minimized. When performing control of transmission release, speed synchronization and transmission engagement, the increased torque supplied from the first motor to the first rotating element of the planetary gear unit is kept constant; After the control of the transmission release is completed, when the torque supplied from the second motor to the first rotating element or the second rotating element of the planetary gear unit is increased, the torque supplied from the first motor to the first rotating element of the planetary gear unit is controlled so that the output torque of the output shaft follows the predetermined target torque.

11. The shift control method for an automatic-manual transmission according to claim 10, wherein, The predetermined target torque remains constant.

12. The shift control method for an automatic-manual transmission according to claim 10, wherein, The predetermined target torque is a target torque that gradually increases in the later stages.

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