Method to control a hybrid powertrain, vehicle comprising such a hybrid powertrain, computer program for controlling such a hybrid powertrain, and a computer program product comprising program code

Patent metadata

Field	Value
Publication number	US-10214218-B2
Application number	US-201515511592-A
Country	US
Kind code	B2
Filing date	Sep 29, 2015
Priority date	Sep 29, 2014
Publication date	Feb 26, 2019
Grant date	Feb 26, 2019

Abstract

A method is provided to control a hybrid powertrain comprising an internal combustion engine, a gearbox, a range gearbox, and two electrical machines to achieve a shift operation from a low range position to a high range position with minimal to no torque interruption and optimal brake regeneration, on the one hand, and a large torque and a lame number of gear steps are achieved on the other hand.

First claim

The invention claimed is:

1. A method to control a hybrid powertrain, in order to achieve a shifting from a low range position to a high range position, wherein the hybrid powertrain comprises an internal combustion engine; a gearbox with an input shaft and an output shaft; a range gearbox connected to the output shaft of the gearbox; a first planetary gear connected to the input shaft of the gearbox; a second planetary gear connected to the first planetary gear; a first electrical machine connected to the first planetary gear; a second electrical machine connected to the second planetary gear; at least one first gear pair connected to the first planetary gear and the output shaft of the gearbox; and at least second one gear pair connected to the second planetary gear and the output shaft of the gearbox, wherein the internal combustion engine is connected to the first planetary gear via the input shaft of the gearbox, said method comprising:
a) engaging a gear by way of connecting two rotatable components in the first planetary gear;
b) connecting the at least one second gear pair connected to the second planetary gear and the output shaft of the gearbox;
c) connecting a sixth gear pair arranged between a countershaft and the range gearbox to the countershaft, so that the countershaft is connected to the output shaft via the range gearbox;
d) controlling the range gearbox from a low range position to a neutral position, in which no torque transmission occurs through the range gearbox;
e) controlling the first electrical machine to achieve a synchronous rotational speed between two rotatable components in the range gearbox;
f) connecting the rotatable components of the range gearbox by means of a displaceable third coupling device; and
g) engaging a gear by connecting two rotatable components in the second planetary gear.

2. The method according to claim 1 , further comprising:
after step f) and before step g):
h) controlling the internal combustion engine, in such a manner that a synchronous rotational speed arises between the two rotatable components in the second planetary gear.

3. The method according to claim 1 , wherein in step f) the two rotatable components in the range gearbox, which are connected with the use of the displaceable third coupling device, consist of a third ring gear and a third planetary wheel carrier in a third planetary gear.

4. The method according to claim 1 further comprising:
following step c) and before step d):
i) disconnecting the rotatable components of the first planetary gear from each other.

5. The method according to claim 1 further comprising:
before step a):
j) preventing a rotatable component in the range gearbox from rotating.

6. The method according to claim 5 , wherein in step j), connecting the first planetary gear to an input shaft to the range gearbox by means of a coupling mechanism.

7. The method according to claim 1 , wherein during step d) and e), a torque is generated by means of the second electrical machine.

8. The method according to claim 1 , wherein in step c), the sixth gear pair is connected to the countershaft, by generating a synchronous rotational speed with the second electrical machine, between the countershaft and a seventh cogwheel of the sixth gear pair.

9. The method according to claim 1 , wherein in step e) the first electrical machine is controlled in such a manner that a third sun wheel in the range gearbox, which is connected to the input shaft of the gearbox to the range gearbox, is controlled in order to generate a synchronous rotational speed between the rotatable components in a third planetary gear of the range gearbox.

10. The method according to claim 9 , wherein in step e), the second electrical machine is operated by electric power from an energy storage device.

11. The method according to claim 1 , wherein the at least one first gear pair, which is connected to the first planetary gear comprises a pinion gear and a cogwheel in engagement with each other, which pinion gear of the first gear pair is fixedly arranged with the first planetary gear, and which cogwheel of the first gear pair is connectable to and disconnectable from the countershaft, wherein in step b) the cogwheel is disconnected from the countershaft.

12. The method according to claim 1 , wherein the at least one second gear pair, which is connected to the second planetary gear, comprises a pinion gear and a cogwheel in engagement with each other, which pinion gear of the second gear pair is fixedly arranged with the second planetary gear, and which cogwheel of the second gear pair is connectable to and disconnectable from the countershaft, wherein in step b) the cogwheel is connected to the countershaft.

13. The method according to claim 1 , further comprising a fifth gear pair which comprises a fifth and sixth cogwheel in engagement with each other, wherein the fifth cogwheel of the fifth gear pair is arranged to be connected and disconnected on the countershaft using a fifth coupling element, wherein, in step b), the fifth cogwheel of the fifth gear pair is disconnected from the countershaft.

14. The method according to claim 1 , wherein an output shaft of the internal combustion engine is connected to a planetary wheel carrier arranged in the first planetary gear.

15. A vehicle with a hybrid powertrain, comprising an internal combustion engine; a gearbox with an input shaft and an output shaft; a range gearbox connected to the output shaft of the gearbox; a first planetary gear connected to the input shaft of the gearbox; a second planetary gear connected to the first planetary gear; a first electrical machine connected to the first planetary gear; a second electrical machine connected to the second planetary gear; at least one first gear pair connected to the first planetary gear and the output shaft of the gearbox; and at least one second gear pair connected to the second planetary gear and the output shaft of the gearbox, wherein the internal combustion engine is connected to the first planetary gear via the input shaft of the gearbox, wherein the hybrid powertrain is controlled according to a method comprising
a) engaging a gear by way of connecting two rotatable components in the first planetary gear;
b) connecting the at least one second gear pair connected to the second planetary gear and the output shaft of the gearbox;
c) connecting a sixth gear pair arranged between a countershaft and the range gearbox to the countershaft, so that the countershaft is connected to the output shaft via the range gearbox;
d) controlling the range gearbox from a low range position to a neutral position, in which no torque transmission occurs through the range gearbox;
e) controlling the first electrical machine to achieve a synchronous rotational speed between two rotatable components in the range gearbox;
f) connecting the rotatable components of the range gearbox by means of a displaceable third coupling device; and
g) engaging a gear by connecting two rotatable components in the second planetary gear.

16. A computer program comprising program code stored in a non-transitory computer-readable medium readable by a computer, said computer program used to achieve a shifting from a low range position to a high range position, wherein the hybrid powertrain comprises an internal combustion engine; a gearbox with an input shaft and an output shaft; a range gearbox connected to the output shaft of the gearbox; a first planetary gear connected to the input shaft of the gearbox; a second planetary gear connected to the first planetary gear; a first elect

Assignees

• Scania Cv Ab

Inventors

• Bergquist Mikael
• Björkman Mathias
• Lindström Johan
• Pettersson Niklas

Classifications

• F16H2306/44

  Removing torque from current gears · CPC title

• F16H2200/201

  with three sets of orbital gears · CPC title

• F16H2061/6602

  with at least two dynamo-electric machines for creating an electric power path inside the transmission device, e.g. using generator and motor for a variable power torque path · CPC title

• F16H2037/102

  the input or output shaft of the transmission is connected or connectable to two or more differentials · CPC title

• F16H2003/008

  comprising means for selectively driving countershafts · CPC title