Methods, systems, and vehicles with electromechanical variable transmission

• US 10,315,643 B2
• Filed: 09/23/2016
• Issued: 06/11/2019
• Est. Priority Date: 03/14/2013
• Status: Active Grant

• Current Assignee: Oshkosh Defense LLC (Oshkosh Corporation)
• Original Assignee: Oshkosh Defense LLC (Oshkosh Corporation)
• Inventors: Shukla, Deepak, Zhang, Rongjun, Nasr, Nader
• Primary Examiner(s): Scott, Jacob S.
• Application Number:
  US15/274,946
• Publication Number:
  US 20170008507A1
• Time in Patent Office: 991 Days
• Field of Search: None
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/34 characterised by the absence of energy storing means
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/387 Actuated clutches, i.e. clutches engaged or disengaged by electric, hydraulic or mechanical actuating means
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/52 Driving a plurality of drive axles, e.g. four-wheel drive
• CPC Class Codes: B60K 6/543 the transmission being a continuously variable transmission
• CPC Class Codes: B60L 50/11 using DC generators and DC motors
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: B60W 2510/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2510/0604 Throttle position
• CPC Class Codes: B60W 2510/0638 Engine speed
• CPC Class Codes: B60W 2510/08 Electric propulsion units
• CPC Class Codes: B60W 2510/081 Speed
• CPC Class Codes: B60W 2520/10 Longitudinal speed
• CPC Class Codes: B60W 2710/021 Clutch engagement state
• CPC Class Codes: B60W 2710/06 Combustion engines, Gas turbines
• CPC Class Codes: B60W 2710/0644 : Engine speed
• CPC Class Codes: B60W 2710/0677 : Engine power
• CPC Class Codes: B60W 2710/08 : Electric propulsion units
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60Y 2200/92 : Hybrid vehicles
• CPC Class Codes: B60Y 2300/42 : Control of clutches
• CPC Class Codes: B60Y 2300/43 : Control of engines
• CPC Class Codes: B60Y 2300/60 : Control of electric machines, e.g. problems related to electric motors or generators
• CPC Class Codes: B60Y 2300/72 : Facilitate disengaging of gears, e.g. by inducing a torque reversal
• CPC Class Codes: B60Y 2400/72 : Continous variable transmissions [CVT]
• CPC Class Codes: B60Y 2400/73 : Planetary gearings
• CPC Class Codes: F16H 1/28 : with gears having orbital motion
• CPC Class Codes: F16H 3/72 : with a secondary drive, e.g. regulating motor, in order to vary speed continuously
• CPC Class Codes: F16H 3/727 : with at least two dynamo electric machines for creating an electric power path inside the gearing, e.g. using generator and motor for a variable power torque path special adapted for a hybrid electric vehicle B60K6/20
• CPC Class Codes: F16H 3/728 : with means to change ratio in the mechanical gearing
• CPC Class Codes: Y02T 10/62 : Hybrid vehicles
• CPC Class Codes: Y02T 10/92 : Energy efficient charging or discharging systems for batteries, ultracapacitors, supercapacitors or double-layer capacitors specially adapted for vehicles
• CPC Class Codes: Y10S 903/906 : Motor or generator
• CPC Class Codes: Y10S 903/91 : Orbital, e.g. planetary gears
• CPC Class Codes: Y10S 903/914 : Actuated, e.g. engaged or disengaged by electrical, hydraulic or mechanical means
• CPC Class Codes: Y10S 903/916 : with plurality of drive axles
• CPC Class Codes: Y10S 903/918 : Continuously variable
• CPC Class Codes: Y10S 903/93 : Conjoint control of different elements

Abstract

A method of operating a first electric machine and a second electric machine in a vehicle drive includes operating the vehicle drive in: a first operating mode by operating the first electric machine in a voltage mode and the second electric machine in a torque mode; and a second operating mode by operating the first electric machine in the torque mode and the second electric machine in the voltage mode.

Claims

1. A method of operating a first electric machine and a second electric machine in a vehicle drive, the first electric machine electrically coupled to the second electric machine by a DC bus and the vehicle drive configured to propel a vehicle, the method comprising:

operating the vehicle drive in a first operating mode by;

operating the first electric machine in a voltage mode, wherein the first electric machine regulates electrical power at the DC bus to maintain a first voltage on the DC bus when operated in the voltage mode; and

operating the second electric machine in a torque mode, wherein the second electric machine consumes electrical power from the DC bus when operated in the torque mode;

wherein a sum of the electrical power regulated by the first electric machine, the electrical power losses, and the electrical power consumed by the second electric machine is zero;

wherein the first electric machine regulates electrical power at the DC bus and the second electric machine consumes electrical power from the DC bus without doing either of (a) providing electrical power to an energy storage device or (b) consuming electrical power from an energy storage device; and

operating the vehicle drive in a second operating mode by;

operating the first electric machine in the torque mode, wherein the first electric machine consumes electrical power from the DC bus when operated in the torque mode; and

operating the second electric machine in the voltage mode, wherein the second electric machine regulates electrical power at the DC bus to maintain a second voltage on the DC bus when operated in the voltage mode;

wherein a sum of the electrical power consumed by the first electric machine, the electrical power losses, and the electrical power regulated by the second electric machine is zero;

wherein the first electric machine consumes electrical power from the DC bus and the second electric machine regulates electrical power at the DC bus without doing either of (a) providing electrical power to an energy storage device or (b) consuming electrical power from an energy storage device.

2. The method of claim 1, wherein the first electric machine provides all of an electrical power required by the second electric machine and an electrical power required to offset electrical power losses in the first operating mode.

3. The method of claim 2, wherein the second electric machine provides all of an electrical power required by first second electric machine and an electrical power required to offset electrical power losses in the second operating mode.

4. The method of claim 1, wherein the first voltage is equal to the second voltage.

5. The method of claim 1, further comprising operating the vehicle drive in an operating state by:

operating both the first electric machine as a generator and the second electric machine as a generator, wherein the first electric machine and the second electric machine provide electrical power to the DC bus to maintain a third voltage on the DC bus when operated as generators, wherein the first electric machine and the second electric machine provide all of the electrical power required to offset electrical power losses when operated as generators, wherein the first electric machine and the second electric machine provide electrical power to the DC bus without doing either of (a) providing electrical power to an energy storage device or (b) consuming electrical power from an energy storage device.

6. The method of claim 5, further comprising switching from the first operating mode to the third operating mode when a first power generation capability associated with the first electric machine is below a first threshold level.

7. The method of claim 6, further comprising switching from the third operating mode to the second operating mode in response to a second power generation capability associated with the second electric machine is greater than a second threshold level.

8. The method of claim 7, wherein at least one of the first threshold level and the second threshold level is equal to the electrical power losses.

9. The method of claim 1, further comprising transmitting a controller area network message with a controller to the first electric machine and the second electric machine, wherein the controller area network message specifies the voltage mode or the torque mode for each electric machine.

10. A system for operating a first electric machine and a second electric machine in a vehicle drive, the first electric machine electrically coupled to the second electric machine by a DC bus and the vehicle drive configured to propel a vehicle, the system comprising a processing circuit configured to:

operate the vehicle drive in a first operating mode by;

operating the first electric machine in a voltage mode, wherein the first electric machine regulates electrical power at the DC bus to maintain a first voltage on the DC bus when operated in the voltage mode; and

operating the second electric machine in a torque mode, wherein the second electric machine consumes electrical power from the DC bus when operated in the torque mode;

wherein a sum of the electrical power regulated by the first electric machine, the electrical power losses, and the electrical power consumed by the second electric machine is zero;

wherein the first electric machine regulates electrical power at the DC bus and the second electric machine consumes electrical power from the DC bus without doing either of (a) providing electrical power to an energy storage device or (b) consuming electrical power from an energy storage device; and

operate the vehicle drive in a second operating mode by;

operating the first electric machine in the torque mode, wherein the first electric machine consumes electrical power from the DC bus when operated in the torque mode; and

operating the second electric machine in the voltage mode, wherein the second electric machine regulates electrical power at the DC bus to maintain a second voltage on the DC bus when operated in the voltage mode;

wherein a sum of the electrical power consumed by the first electric machine, the electrical power losses, and the electrical power regulated by the second electric machine is zero;

wherein the first electric machine consumes electrical power from the DC bus and the second electric machine regulates electrical power at the DC bus without doing either of (a) providing electrical power to an energy storage device or (b) consuming electrical power from an energy storage device.

11. The system of claim 10, wherein the first voltage is equal to the second voltage.