Drivetrain with infinitely and electrically variable transmission capabilities

Patent metadata

Field	Value
Publication number	US-12485774-B2
Application number	US-202318539103-A
Country	US
Kind code	B2
Filing date	Dec 13, 2023
Priority date	May 7, 2021
Publication date	Dec 2, 2025
Grant date	Dec 2, 2025

Abstract

Methods and systems are provided for an electric drive train of a vehicle. In one example, a four-node planetary gear set is included in the electric drive train with a first motor coupled to a first input node and a second motor coupled to a second input node of the four-node planetary gear set. The drive train may be operated at a first mechanical point when the first electric machine is operated at a substantially zero speed, and the drive train may be operated at a second mechanical point when the second electric machine is operated at a substantially zero speed, in one or more examples. Operation at either the first mechanical point or the second mechanical point may be achieved without clutches or hydro-mechanical devices.

First claim

The invention claimed is:

1 . A drive train for a hybrid electric vehicle (HEV), comprising:
a four-node planetary gear set; a first motor coupled to a first input node and a second motor coupled to a second input node of the four-node planetary gear set; an engine coupled to a third input node of the four-node planetary gear set, the third input node positioned between the first input node and the second input node, wherein torque generated by each of the first motor, the second motor, and the engine is summed at an output node of the four-node planetary gear set, the output node positioned between the third input node and one of the first input node and the second input node, and wherein the first motor and the second motor are asymmetric; and a controller with instructions stored therein to operate the second motor at a higher and wider speed and torque range than the first motor, and to operate in a mode that includes both a cruise sub-mode and a vehicle launch sub-mode achieved by inverting a speed and torque sign of the first motor.

2 . The drive train of claim 1 , wherein the first motor is coupled to the first input node and the second motor is coupled to the second input node without clutches, and wherein the controller is further configured to operate one of the first motor and the second motor in a speed control mode and the other of the first motor and the second motor in a torque control mode, including altering a speed setpoint of the first motor in the speed control mode to change a power ratio between the asymmetric first motor and second motor.

3 . The drive train of claim 1 , wherein the drive train is operated at a first mechanical point when the first motor is commanded to operate at zero speed and the second motor provides torque to supplement torque generated by the engine.

4 . The drive train of claim 1 , wherein the drive train is operated at a second mechanical point when the second motor is commanded to operate at zero speed and the first motor provides torque to supplement torque generated by the engine.

5 . The drive train of claim 1 , wherein the four-node planetary gear set is a Ravigneaux gear set, and wherein the first motor is coupled to a first sun gear and the second motor is coupled to a second sun gear of the Ravigneaux gear set.

6 . The drive train of claim 5 , wherein the engine is coupled to a ring gear of the Ravigneaux gear set and the output node is located at a carrier of the Ravigneaux gear set.

7 . The drive train of claim 5 , wherein the engine is coupled to a carrier of the Ravigneaux gear set and the output node is located at a ring gear of the Ravigneaux gear set.

8 . The drive train of claim 1 , wherein the controller is further configured to operate the first motor as a low speed, high torque device in a torque control mode.

9 . The drive train of claim 8 , wherein the controller is further configured to operate the second motor as a comparatively high speed, low torque device in a speed control mode.

10 . A drive train for a hybrid electric vehicle (HEV), comprising:
a four-node planetary of the drive train, the four-node planetary of the drive train comprising an output node; a first electric machine, the drive train operated at a first mechanical point when the first electric machine is operated at a substantially zero speed; a second electric machine, the drive train operated at a second mechanical point when the second electric machine is operated at a substantially zero speed, wherein the first electric machine and the second electric machine are coupled to an input node on opposite sides of the output node, and wherein, during a first power split mode,
the first electric machine is configured to operate at the substantially zero speed, and
the second electric machine is configured to supplement torque provided by an engine of the HEV, wherein the first electric machine and the second electric machine are asymmetric with different operating speed and torque ranges; and
a controller configured to operate the first electric machine as a low speed, high torque device in a torque control mode, and to operate the second electric machine as a comparatively high speed, low torque device in a speed control mode.

11 . The drive train of claim 10 , wherein operation at either the first mechanical point or the second mechanical point is achieved without clutches or hydro-mechanical devices.

12 . The drive train of claim 10 , wherein both the first electric machine and the second electric machine are configured to provide torque in a dual motor operation mode.

13 . The drive train of claim 10 , wherein only the second electric machine supplements the torque provided by the engine in the first power split mode.

14 . The drive train of claim 10 , wherein, during a second power split mode:
the first electric machine is configured to supplement torque provided by the engine of the HEV, and the second electric machine is configured to operate at zero speed.

15 . The drive train of claim 10 , wherein the first mechanical point is an operating condition where a transmission is turning while the first electric machine controlling a speed ratio of the transmission is operated at the substantially zero speed.

16 . A method for a drive train for a hybrid electric vehicle (HEV) with a first electric machine and a second electric machine, comprising:
outputting torque at an output node of a four-node planetary of the drive train by operating the drive train at a first mechanical point of two mechanical points when the drive train is in a power split mode, wherein operation at the first mechanical point is enabled when the first electric machine of the drive train is commanded to operate at zero speed and the second electric machine of the drive train supplements torque provided by an engine of the HEV, the first and second electric machines coupled to input nodes arranged on opposite sides of the output node of the four-node planetary, and operating the first electric machine as a low speed, high torque device in a torque control mode, and operating the second electric machine as a comparatively high speed, low torque device in a speed control mode.

17 . The method of claim 16 , wherein outputting torque at the output node further includes operating the drive train at a second mechanical point of the two mechanical points, and wherein operation at the second mechanical point is enabled when the second electric machine of the drive train is commanded to operate at zero speed and the first electric machine supplements torque provided by the engine of the HEV.

18 . The method of claim 17 , wherein operating the drive train at each of the first mechanical point and the second mechanical point includes adjusting operation of the drive train between dual motor operation and single motor operation without use of a clutch.

19 . The method of claim 16 , wherein outputting torque at the output node of the four-node planetary includes outputting torque at one of a Ravigneaux gear set, a pair of simple planetary gear sets, compound planetary gear sets, and stepped planetary gear sets.

Assignees

• Dana Heavy Vehicle Sys Group

Inventors

• David Jeffrey M
• Miller Travis J
• Davis Mark A

Classifications

• B60Y2400/73

  Planetary gearings · CPC title

• B60L15/2045

  for optimising the use of energy · CPC title

• B60L2240/423

  Torque · CPC title

• B60L2240/12

  Speed · CPC title

• B60L2240/421

  Speed · CPC title