JP2006010044A - Sudden shift control device for hybrid transmission - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To actualize compensation for the shift speed of a hybrid transmission which performs shift operation with a motor/generator even when a sudden shift exceeding the limit of the capability of the motor/generator is requested. <P>SOLUTION: During the sudden shift of the hybrid transmission from a current shift condition shown by a solid line lever into a target shift condition shown by a dashed line lever, an engine-side speed (an engine speed) of an engine clutch E/C is increased to a value higher than a transmission-side speed (an E-point equivalent value) of the engine clutch E/C, preferably to a speed at a F-point corresponding to a target shift ratio shown by the dashed line lever and furthermore the engine clutch E/C is slip-joined. Thus, the transmission-side speed (the E-point equivalent value) of the engine clutch E/C is helped to be increased to a F-point equivalent value shown by the same and a low-side shift is promoted to be attained by the increase of rotation. Thereby, the compensation for the shift speed is actualized as required in sudden low-side shift exceeding the limit of the capability of the motor/generator MG1, MG2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a technique for appropriately performing a shift when a sudden shift request of a hybrid transmission is generated during electric travel.

  The hybrid transmission is configured by connecting the engine, the output shaft, and the motor / generator to each other by a differential device, and the vehicle can be electrically driven only by the power from the motor / generator. Hybrid driving can be performed by the power from the motor / generator, and a shift can be performed by the motor / generator in any driving mode.

Thus, in a shift control device for a hybrid transmission that creates a gear ratio by a motor / generator, conventionally, as described in Patent Document 1, for example, the engine speed during hybrid travel is set to a constant value that achieves optimum fuel consumption, for example. In general, the hybrid transmission is shift-controlled so as to be maintained.
Further, at the time of deceleration, the target gear ratio is determined according to the traveling state such as the required driving force and the vehicle speed, and the hybrid transmission is decelerated while controlling the shift so that the actual gear ratio follows this.
JP 2000-034154 A

By the way, in the hybrid transmission, among the rotating elements constituting the differential device, if the rotating element related to the engine and the engine are always coupled, the engine is not used during the electric travel, although the engine is not used. Since the vehicle travels by dragging, the energy loss increases.
Therefore, it is general that an engine clutch is interposed between the rotating element related to the engine and the engine so that these can be appropriately separated.

  When shifting the hybrid transmission during electric travel, the gear is controlled only by the motor / generator with the engine clutch released, but the motor / generator is limited by torque limit, power limit, inverter limit, etc. Therefore, when there is a sudden change in the driving condition that requires a sudden shift exceeding this, the shift cannot be performed at the requested speed, and the target gear ratio is transiently changed. It will not be realized, causing a problem that the power performance is adversely affected.

According to the present invention, if the engine clutch is slip-coupled, the shift can be promoted (assisted) by controlling the engine speed, and the lack of the shift speed at the time of the sudden shift request can be compensated. Based on fact recognition,
It is an object of the present invention to propose a new rapid transmission control device for a hybrid transmission that can embody this idea and solve the above problems.

For this purpose, the rapid transmission control device for a hybrid transmission according to the present invention is as follows.
First, the premised hybrid transmission is configured such that the engine, the output shaft, and the motor / generator are connected to each other by a differential device and can be shifted by the motor / generator, and constitutes the differential device. Among the rotating elements, a rotating element related to the engine and an engine clutch interposed between the engines.

In the present invention, the following configuration is added to the hybrid transmission.
In other words, during a sudden change in the driving state in which the shift becomes a sudden shift while the engine clutch is released, the engine speed is controlled to change in a direction corresponding to the shift direction, and the engine clutch is slip-coupled. The above-described speed change is promoted by engine rotation.

According to the sudden speed change control device of the present invention, at the time of a sudden speed change request in a traveling state with the engine clutch released, the engine speed is controlled to change in a direction corresponding to the speed change direction and the engine clutch is slip-coupled. Thus, the above-mentioned shift can be promoted by the engine rotation (shift assist).
Even if the motor / generator is subject to operation limitations such as torque limit, power limit, inverter limit, etc. and sudden shift is requested, even if it cannot shift at the requested speed, the above-mentioned shift assist will The shift speed can be compensated, and the above-mentioned problem that the target speed ratio is not realized transiently and the power performance is adversely affected can be solved.

Hereinafter, embodiments of the present invention will be described in detail based on examples shown in the drawings.
FIG. 1 shows a drive system of a vehicle equipped with a hybrid transmission 1 equipped with a sudden speed change control device of the present invention together with the control system.
The vehicle drive system includes a hybrid transmission 1, an engine 2 on the input side thereof, an engine clutch E / C interposed therebetween, a differential gear device 3 on the output side of the hybrid transmission 1, and a hybrid transmission. The output from the machine 1 is composed of left and right drive wheels 4L and 4R that are distributed and transmitted by the differential gear device 3.

The hybrid transmission 1 has the following configuration as shown in FIG. 2 and is useful for use as a transaxle for a front engine / front wheel drive vehicle (FF vehicle), and includes a differential gear device 3.
The hybrid transmission 1 will be described in detail with reference to FIG. 2, which comprises two simple planetary gear sets 21 and 22 arranged coaxially in the axial direction (left and right in the figure).
The planetary gear set 21 on the side close to the engine 2 is constituted by a ring gear R1, a sun gear S1, and a pinion P1 meshed with these gears,
The planetary gear set 22 on the side far from the engine 2 is constituted by a ring gear R2, a sun gear S2, and a pinion P2 meshed with these gears.

Here, the pinion P1 of the planetary gear set 21 is a small-diameter long pinion extending to the planetary gear set 22, the pinion P2 of the planetary gear set 22 is a large-diameter short pinion, and the small-diameter long P1 is a large-diameter short pinion. Mesh with P2,
These pinions P1 and P2 are rotatably supported on a common carrier C so that the planetary gear sets 21 and 22 constitute a Ravigneaux type planetary gear set.
This Ravigneaux type planetary gear set corresponds to the differential in the present invention.

A compound current two-layer motor 23 is provided on the side far from the engine 2 across the Ravigneaux planetary gear set, and is housed in the transmission case 24 together with the Ravigneaux planetary gear set.
The composite current two-layer motor 23 includes an inner rotor 23ri and an annular outer rotor 23ro that surrounds the inner rotor 23ri so as to be coaxially rotatable in the transmission case 24, and between the inner rotor 23ri and the outer rotor 23ro. An annular stator 23 s arranged coaxially in the annular space is fixed to the transmission case 1.

In the composite current two-layer motor 23, the outer rotor 23ro and the annular stator 23s constitute a first motor / generator MG1, and the annular stator 23s and the inner rotor 23ri constitute a second motor / generator MG2.
The first motor / generator MG1 (outer rotor 23ro) is coupled to the sun gear S1 in the Ravigneaux type planetary gear set, and the second motor / generator MG2 (inner rotor 23ri) is coupled to the sun gear S2 in the Ravigneaux type planetary gear set. To do.

Further, the ring gear R2 in the Ravigneaux type planetary gear set can be appropriately fixed by the low brake L / B, and the sun gear S2 can be appropriately fixed by the overdrive brake OD / B.
The ring gear R1 is an input element and can be coupled to the engine 3 via the engine clutch E / C.
Further, the carrier C is an output element, and the output gear 25 is coaxially coupled to the output element 25, and the counter gear 26 is engaged with the output gear 25.
The counter gear 26 is connected to a counter shaft 27, and a final drive pinion 28 is further connected to the counter shaft 27.
Then, the final drive pinion 28 is engaged with the final drive ring gear 29 coupled to the differential gear device 3.

The hybrid transmission 1 described above with reference to FIG. 2 is represented by the collinear diagram of FIG. 3, in which In indicates input from the engine 2, and Out indicates output to the wheels 4L and 4R. α, β, and γ mean the ratio of the distance between the rotating elements determined by the gear ratio of the planetary gear sets 21 and 22, respectively.
As shown by the lever LB in FIG. 3, in the shift (LB) mode in which the low brake L / B is engaged and the ring gear R2 is fixed at the rotation speed 0, the lever LB on the nomograph rotates with A as a fulcrum. Therefore, the gear ratio fixed mode is set, and the torque from the engine 2 (input In) and the torque from the motor / generator MG1, MG2 are increased to the output Out by the lever ratio, so the low brake L / B is released. A larger driving force can be directed to the wheels 4L, 4R than in the case where the vehicle is present.
Therefore, the LB mode with a fixed gear ratio is used when starting a vehicle that requires a large driving force.

When driving at a high speed, where the wheels 4L and 4R are required to be driven at a high speed, as shown by a lever OD in FIG. 3, the overdrive brake OD / B is fastened to fix the sun gear S1 at a rotational speed of zero.
At this time, since the lever OD on the nomograph rotates around B as a fulcrum, the gear ratio is fixed in this case as well, but here the rotation of the engine 2 (input In) is increased at that lever ratio and output. Since it leads to Out, high-speed rotation can be directed to the wheels 4L and 4R as compared with the case where the overdrive brake OD / B is released.
Therefore, the OD mode with a fixed gear ratio is used when the vehicle is traveling at a high speed where high-speed rotation of the output Out is required.

  When running with both the low brake L / B and overdrive brake OD / B released, the motor / generator MG1, MG2 can be continuously variable, and the rotational speed limits of the motor / generator MG1, MG2 and engine 2 are limited. The shift state at the high speed limit determined by is as shown by lever MAX in FIG.

All of the above are gear shift states during hybrid driving. However, in order to make the vehicle travel electric (EV) only by the motor / generators MG1, MG2, the rotation of the ring gear R1 coupled to the engine as shown by lever EV in FIG. The motor / generator MG1 is driven to rotate in reverse while the number is kept at 0, and the motor / generator MG2 is driven to rotate forward so that only the motor / generator MG1, MG2 is used as a power source to extract forward rotation from the output Out. Do it like this.
In shifting control during electric travel, the required shifting can be performed by controlling the reverse rotation speed of the motor / generator MG1 and the forward rotation speed of the motor / generator MG2.
As described above, when the rotational speed of the ring gear R1 coupled to the engine is kept at 0 during electric traveling, it is not always necessary to release the engine clutch E / C. However, in this embodiment, the engine clutch E / C is not operated during electric traveling. Let C be released.

  When the vehicle travels backward, as shown by a lever REV in FIG. 3, the motor / generator MG1 is driven to rotate forward while the rotational speed of the ring gear R1 coupled to the engine is kept at 0, and the motor / generator MG2 is driven. Is driven in reverse rotation to extract reverse rotation from the output Out using only the motor / generator MG1, MG2 as a power source.

As shown in FIG. 1, the vehicle drive system control system configured by inserting the hybrid transmission 1 as described above is an engine controller that controls the engine 2 including a rotational speed control for sudden shift control, which will be described later. 5, a clutch controller 6 including a hydraulic power source for controlling the engagement force of the engine clutch E / C, motor controllers 7 and 8 for controlling the motor / generators MG1 and MG2 in the hybrid transmission 1, and a low brake L / B A low brake controller 9 including a hydraulic power source that controls the fastening force of the overdrive brake, an overdrive brake controller 10 that includes a hydraulic power source that controls the fastening force control of the overdrive brake OD / B, and an integrated controller 11 for these controllers 5 to 10. Constitute.
The integrated controller 11 performs predetermined calculations based on various types of input information, and controls the corresponding parts via the controllers 5 to 10 as usual, as well as the rapid shift control targeted by the present invention as described later. Shall be executed.

  Here, in the above hybrid transmission, since the motor / generator MG1, MG2 controls the shift control, the operating speed limited by the torque limit, power limit, inverter limit, etc. of the motor / generator has been exceeded. When there is a sudden change in the driving condition that requires sudden gear shifting, gear shifting cannot be performed at the required speed, and the target gear ratio will not be realized transiently, resulting in an adverse effect on power performance. Arise.

In order to solve this problem, in this embodiment, the integrated controller 11 in FIG. 1 executes the control program shown in FIG. 4 to perform shift control during electric (EV) travel.
First, in step S1, it is checked whether or not the above sudden shift request has occurred. When making this determination, it is possible to determine that a sudden gear change request has occurred when the actual gear ratio becomes unable to follow the target gear ratio due to the torque limit, power limit, inverter limit, etc. of the motor / generator MG1, MG2. it can.

If it is not a sudden shift, the above-described normal electric (EV) travel shift control is executed in step S2. However, if there is a sudden shift request, the control is advanced to step S3 and thereafter, and the sudden shift targeted by the present invention is performed. Shift control is performed.
In this sudden shift control, first, in step S3, it is determined whether or not the sudden shift request is a low shift toward the shift ratio on the low side with respect to the current shift ratio (the sudden shift request is the current shift ratio). It is determined whether it is a high-side shift toward a higher gear ratio.

In the case where it is determined in step S3 that the shift is the low side, this is a shift in which the motor / generators MG1 and MG2 change the hybrid transmission from the current shift state indicated by the solid line lever in FIG. If
First, in step S4, the engine side rotational speed (engine rotational speed) of the engine clutch E / C is set higher than the transmission side rotational speed of the engine clutch E / C (value corresponding to point E in FIG. 6). Rotational speed control is performed to provide a rotational difference according to the speed change direction.
In this engine speed control, it is best to increase the engine speed to the speed at the point F corresponding to the target gear ratio indicated by the broken line lever in FIG.

  In addition to the engine speed control, in step S5, the engine clutch E / C is slip-coupled, and the transmission-side speed of the engine clutch E / C (corresponding to the point E in FIG. 6) is F in FIG. It is possible to assist the increase toward the point equivalent value, and the low-side shift achieved by the increase in the rotation can be promoted by the engine speed control and the engine clutch control.

Conventionally, only the motors / generators MG1 and MG2 perform the above-mentioned low-side shift. Therefore, the motor / generator torque limit, power limit, inverter limit, etc. limit the operation, and as required during sudden low-side shifts. The shifting speed of
According to the present embodiment, this shift can be promoted as described above by the engine speed control and the slip coupling of the engine clutch, and the requested shift speed can be compensated even when a sudden low shift is requested. This can solve the problem that the target speed ratio is not realized transiently and the power performance is adversely affected.

  As described above, when the engine speed is increased to the speed at the point F corresponding to the target speed ratio indicated by the broken line lever in FIG. 6, the acceleration of the low side shift becomes excessive or insufficient. Can be prevented, and the adverse effects of the engine speed control can be eliminated.

On the other hand, when it is determined in step S3 that the gear shift is the high side, that is, the motor / generators MG1 and MG2 change the hybrid transmission from the current shift state indicated by the solid line lever in FIG. If it is,
First, in step S6, the engine-side rotational speed (engine rotational speed) of the engine clutch E / C is made lower than the transmission-side rotational speed of the engine clutch E / C (corresponding to the point G in FIG. 7). Rotational speed control is performed to provide a rotational difference according to the speed change direction.
In this engine speed control, it is best to reduce the engine speed to the speed at point H corresponding to the target gear ratio indicated by the broken line lever in FIG.

  In addition to the engine speed control, in step S5, the engine clutch E / C is slip-coupled, and the transmission-side speed of the engine clutch E / C (corresponding to the point G in FIG. 7) is H in FIG. It is possible to assist the reduction toward the point equivalent value, and the high-side shift achieved by the reduction in the rotation can be promoted by the engine speed control and the engine clutch control.

Conventionally, only the motors / generators MG1 and MG2 perform the above-mentioned high-side shift. Therefore, the motor / generator torque limit, power limit, inverter limit, etc. limit the operation, and as required during sudden high-side shifts. The shifting speed of
According to the present embodiment, this shift can be promoted as described above by the engine speed control and the slip coupling of the engine clutch, and the requested shift speed can be compensated even when a sudden high-side shift request is made. This can solve the problem that the target speed ratio is not realized transiently and the power performance is adversely affected.

  As described above, when the engine speed is increased to the speed at the point H corresponding to the target gear ratio indicated by the broken line lever in FIG. 7, the acceleration of the high side shift becomes excessive or insufficient. Can be prevented, and the adverse effects of the engine speed control can be eliminated.

  The low-side sudden shift control in step S4 and step S5 described above or the high-side sudden shift control in step S6 and step S5 described above continues until the end of the shift in which it is determined in step S7 that the target gear ratio has been achieved. When it is determined in S7 that the shift has been completed, the rapid shift control according to the present invention is terminated.

FIG. 5 is an electric (EV) traveling speed change control program showing another embodiment of the present invention. This embodiment is not limited to the slip coupling of the engine clutch E / C, and the low brake L / B or By the cooperative control with the slip coupling of the overdrive brake OD / B, the shift can be further promoted as compared with the above-described embodiment.
For this reason, in this embodiment, as shown in FIG. 5, step S5 and step S7 in FIG. 4 are replaced with step S11 to step S14 to construct an electric (EV) running speed shift control program.

At the time of the low-side sudden shift determined as the low-side shift in step S3, the engine speed is controlled in step S4 by the engine speed control similar to that described above with reference to FIG. F point equivalent value).
Next, in step S11, the engine clutch E / C is slip-engaged and the low brake L / B is slip-engaged in the same manner as in step S5 of FIG. 4, and the engine clutch E / C and the low brake L / B are connected. By controlling the slip coupling force in a coordinated manner, the engagement capacity of the slip coupling is made larger than in the case of the above-described embodiment, so that the transmission side rotation speed of the engine clutch E / C (the value corresponding to point E in FIG. 6) It is possible to assist the increase toward the F point equivalent value with a greater force, and to further promote the low-side shift more strongly, making the operational effects of the above-described embodiment more remarkable.

On the other hand, at the time of the high-side sudden shift that is determined to be the high-side shift in step S3, the engine speed is controlled in step S6 by the engine speed control similar to that described above with reference to FIG. 7 equivalent to H point).
Next, in step S12, the engine clutch E / C is slip-engaged and the overdrive brake OD / B is slip-engaged in the same manner as in step S6 of FIG. 4, and the engine clutch E / C and overdrive brake OD / By cooperatively controlling the slip coupling force of B, the engagement capacity of the slip coupling is made larger than in the case of the above-described embodiment, and the transmission side rotational speed of the engine clutch E / C (the value corresponding to the G point in FIG. 7) is It is possible to assist the increase toward the value corresponding to the H point in the figure with a greater force, and to promote the high-side shift more powerfully, thereby making the operational effects of the embodiment more remarkable.

  The above-described low-side sudden shift control at step S4 and step S11 or the above-described high-side sudden shift control at step S6 and step S12 is continued until the end of shift where it is determined that the target gear ratio has been achieved in step S13 or step S14. When it is determined in step S13 or step S14 that the shift has been completed, the rapid shift control according to the present invention is terminated.

  Although not shown, slip engagement of the engine clutch E / C is performed in the gear ratio fixed mode (the shift state indicated by the lever LB or OD in FIG. 3) in which the low brake L / B or the overdrive brake OD / B is engaged. It goes without saying that acceleration assist and deceleration assist can be performed by control.

1 is a system diagram showing a drive system of a vehicle equipped with a hybrid transmission equipped with a rapid transmission control device according to an embodiment of the present invention, together with the control system. FIG. 2 is a diagrammatic longitudinal side view of the hybrid transmission in FIG. 1. FIG. 3 is a collinear diagram of the hybrid transmission shown in FIG. 2. It is a flowchart which shows the sudden shift control program at the time of the electric driving | running | working which the integrated controller in FIG. 1 performs. It is a flowchart which shows the other embodiment of this invention and shows the sudden gear shift control program at the same time as FIG. FIG. 5 is an alignment chart used for explaining the operation of the low-side sudden shift when the electric travel sudden shift control program shown in FIG. 4 is executed. FIG. 5 is an alignment chart used for explaining the operation of the high-side sudden shift when the electric travel sudden shift control program shown in FIG. 4 is executed.

Explanation of symbols

1 Hybrid transmission 2 Engine
E / C engine clutch 3 Differential gear unit
4L left drive wheel
4R Right drive wheel 5 Engine controller 6 Clutch controller
7,8 Motor controller 9 Low brake controller
10 Overdrive brake controller
11 Integrated controller
21 Simple planetary gear set (differential device)
22 Simple planetary gear set (differential device)
25 Output gear
27 Countershaft
MG1, MG2 Motor / Generator

Claims (5)

The engine, the output shaft, and the motor / generator are connected to each other by a differential device and can be shifted by the motor / generator. Of the rotating elements constituting the differential device, the engine is related to the engine. In a hybrid transmission in which an engine clutch is interposed between a rotating element and an engine,
When the engine clutch is disengaged and the driving speed is suddenly changed, the engine speed is controlled to change in a direction corresponding to the speed change direction and the engine clutch is slip-coupled. A rapid transmission control device for a hybrid transmission, wherein the shift is accelerated by engine rotation. The rapid transmission control device for a hybrid transmission according to claim 1,
A rapid shift control device for a hybrid transmission, wherein the engine speed is controlled in accordance with a required gear ratio. Of the rotating elements constituting the differential device, by fixing one rotating element other than the rotating elements related to the engine and the output shaft, the driving force is greater than when the one rotating element is unlocked. The other one rotating element is released from being fixed by fixing a low brake that allows the engine to face the output shaft and one rotating element other than the rotating element related to the engine and the output shaft. 2. The rapid transmission control device for a hybrid transmission according to claim 1, further comprising an overdrive brake that enables high-speed rotation to be directed toward the output shaft.
At the time of sudden change of the driving state in which the shift becomes a sudden shift, the low brake or the overdrive brake is also slip-coupled according to the shift direction, and by cooperative control of the slip coupling of the brake and the slip coupling of the engine clutch, A rapid transmission control apparatus for a hybrid transmission, characterized in that the transmission is promoted. The rapid transmission control device for a hybrid transmission according to any one of claims 1 to 3,
The hybrid transmission is characterized in that the sudden shift is determined when the shift becomes impossible to follow the demand due to the torque limit, motor power limit, or inverter limit of the motor / generator. Shift control device. The rapid transmission control device for a hybrid transmission according to claim 3 or 4,
A rapid transmission control device for a hybrid transmission, wherein acceleration assist and deceleration assist are performed by slip engagement control of the engine clutch in a gear ratio fixed mode in which the low brake or overdrive brake is engaged.

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