Optimal selection of blended braking capacity for a hybrid electric vehicle

• US 8,145,397 B2
• Filed: 10/22/2008
• Issued: 03/27/2012
• Est. Priority Date: 11/04/2007
• Status: Active Grant

• Current Assignee: Bayerische Motoren Werke AG, Daimler AG (Mercedes-Benz Group AG), Chrysler Group LLC (Stellantis NV)
• Original Assignee: Bayerische Motoren Werke AG, GM Global Technology Operations LLC (General Motors Company), Daimler AG (Mercedes-Benz Group AG), Chrysler LLC (Stellantis NV)
• Inventors: Heap, Anthony H., McConnell, Jason J, McGrath, Seamus T
• Primary Examiner(s): Cheung, Mary
• Assistant Examiner(s): Do, Truc M
• Application Number:
  US12/255,754
• Publication Number:
  US 20090118957A1
• Time in Patent Office: 1,252 Days
• Field of Search: 701/22, 701/51, 701/54, 477/181
• US Class Current: 701/51
• CPC Class Codes: B60K 1/02 comprising more than one electric motor
• CPC Class Codes: B60K 6/26 characterised by the motors or the generators
• CPC Class Codes: B60K 6/365 with the gears having orbital motion
• CPC Class Codes: B60K 6/445 Differential gearing distribution type
• CPC Class Codes: B60K 6/547 the transmission being a stepped gearing
• CPC Class Codes: B60L 2240/423 Torque
• CPC Class Codes: B60L 2240/486 Operating parameters
• 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 10/115 with planetary gears
• CPC Class Codes: B60W 10/18 including control of braking systems
• CPC Class Codes: B60W 10/26 for electrical energy, e.g. batteries or capacitors
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• 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 2510/24 Energy storage means
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/10 Accelerator pedal position
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 2710/027 Clutch torque
• CPC Class Codes: B60W 2710/083 : Torque
• CPC Class Codes: B60W 2710/105 : Output torque
• CPC Class Codes: F16H 2037/0866 : Power split variators with distributing differentials, with the output of the CVT connected or connectable to the output shaft
• CPC Class Codes: F16H 2037/102 : the input or output shaft of the transmission is connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/104 : Power split variators with one end of the CVT connected or connectable to two or more differentials
• CPC Class Codes: F16H 2037/106 : with switching means to provide two variator modes or ranges
• 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 10/64 : Electric machine technologies in electromobility

Abstract

A hybrid powertrain system includes a transmission operative to transfer power between an input member and a torque machine and an output member coupled to a driveline coupled to a wheel including an actuable friction brake. The torque machine is operative to react torque transferred from the wheel through the driveline to the output member of the transmission. The torque machine is connected to an energy storage device. A method for operating a hybrid powertrain system includes monitoring an operator torque request input to an accelerator pedal, determining a minimum available power output of the energy storage device, determining a preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device, determining a regenerative braking torque capacity comprising a torque range between the preferred output torque reacted through the output member to the driveline and the operator torque request input to the accelerator pedal, and controlling operation of the hybrid powertrain based upon the regenerative braking torque capacity.

Claims

1. Method for operating a hybrid powertrain system including a transmission operative to transfer power between an input member and a torque machine and an output member coupled to a driveline coupled to a wheel including an actuable friction brake, the torque machine operative to react torque transferred from the wheel through the driveline to the output member of the transmission, the torque machine connected to an energy storage device, the method comprising:

monitoring an operator torque request input to an accelerator pedal;

determining a minimum available power output of the energy storage device;

determining a preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device;

determining a regenerative braking torque capacity comprising a torque range between the preferred output torque reacted through the output member to the driveline and the operator torque request input to the accelerator pedal; and

controlling operation of the hybrid powertrain based upon the regenerative braking torque capacity.

2. The method of claim 1, further comprising:

determining an immediate accelerator output torque request based upon the operator input to the accelerator pedal; and

determining the regenerative braking torque capacity based upon the preferred output torque reacted through the output member to the driveline and the immediate accelerator output torque request.

3. The method of claim 2, wherein the minimum power output from the energy storage device comprises a maximum charging power for charging the energy storage device at a powertrain system operating point.

4. The method of claim 1, further comprising determining the preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device and torque constraints on the hybrid transmission.

5. The method of claim 4, wherein the minimum available power output of the energy storage device comprises a maximum charging power.

6. The method of claim 1, further comprising

monitoring operator input to a brake pedal and determining an immediate brake output torque request based upon the operator input to the brake pedal during an operator brake request;

and

controlling torque output of the power generating device based upon the immediate brake output torque request and the preferred regenerative braking capacity.

7. The method of claim 1, further comprising selectively applying torque transfer clutches of the transmission to transfer power between the torque machine and the output member in one of fixed gear and continuously variable operating range states.

8. The method of claim 7, further comprising:

commanding a shift from the fixed gear operating range state including operating in the continuously variable operating range state; and

controlling output torque from the transmission in the continuously variable operating range state based upon the regenerative braking torque capacity.

9. The method of claim 7, further comprising determining the preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device and a clutch reactive torque for the selectively applied torque transfer clutch.

10. Method for operating a hybrid powertrain system including a transmission operative to transfer power between an input member and a plurality of torque machines and an output member coupled to a driveline coupled to a wheel including an actuable friction brake, one of the torque machines operative to react torque transferred from the wheel through the driveline to the output member of the transmission, the torque machines are connected to an energy storage device;

the method comprising;

monitoring an operator torque request input to an accelerator pedal;

determining a minimum available power output of the energy storage device;

determining a preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device;

determining a regenerative braking torque capacity comprising a torque range between the preferred output torque reacted through the output member to the driveline and the operator torque request input to the accelerator pedal, and

controlling operation of the hybrid powertrain based upon the regenerative braking torque capacity.

11. The method of claim 10, further comprising selectively applying torque transfer clutches of the transmission to transfer power between the torque machines and the output member in one of fixed gear and continuously variable operating range states.

12. The method of claim 11, further comprising:

commanding a shift from one of the fixed gear operating range states including operating in the continuously variable operating range state; and

controlling output torque from the transmission in the continuously variable operating range state based upon the regenerative braking torque capacity.

13. The method of claim 12, further comprising:

commanding a shift from the fixed gear operating range state including operating in the continuously variable operating range state; and

controlling output torque from the transmission in the continuously variable operating range state based upon the regenerative braking torque capacity.

14. The method of claim 13, further comprising determining the preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device and clutch reactive torque for the selectively applied torque transfer clutch.

15. The method of claim 14, comprising determining motor torque commands for controlling the torque machines based upon the preferred output torque reacted through the output member to the driveline.

16. Method for operating a hybrid powertrain system including a transmission operative to transfer power between an input member and a plurality of torque machines and an output member coupled to a driveline coupled to a wheel, the transmission operative to transfer power between the input member and the torque machines and the output member in one of a fixed gear and a continuously variable operating range state through selective actuation of torque transfer clutches, the torque machines are connected to an energy storage device, and one of the torque machines operative to react torque transferred from the wheel through the driveline to the output member of the transmission, the method comprising:

monitoring an operator torque request input to an accelerator pedal;

determining a minimum available power output of the energy storage device;

determining a preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device;

determining a regenerative braking torque capacity comprising a torque range between the preferred output torque reacted through the output member to the driveline and the operator torque request input to the accelerator pedal; and

controlling operation of the hybrid powertrain based upon the regenerative braking torque capacity.

17. The method of claim 16, further comprising:

commanding a shift from one of the fixed gears including operating in the continuously variable operating range state; and

controlling output torque from the transmission in the continuously variable operating range state based upon the regenerative braking torque capacity.

18. The method of claim 17, further comprising determining the preferred output torque reacted through the output member to the driveline based upon the minimum available power output of the energy storage device and clutch reactive torque for the selectively applied torque transfer clutch.

19. The method of claim 18, comprising determining motor torque commands for controlling the torque machines based upon the preferred output torque reacted through the output member to the driveline.