Method for determining preferred input operating points for a vehicle transmission

• US 20050080539A1
• Filed: 10/14/2003
• Published: 04/14/2005
• Est. Priority Date: 10/14/2003
• Status: Active Grant

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations Incorporated (Motors Liquidation Co. GUC Trust)
• Inventors: Heap, Anthony H., Cawthorne, William R., Hubbard, Gregory A.
• Granted Patent: US 7,110,871 B2
• Time in Patent Office: Days
• US Class Current: 701/54
• 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 10/26 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 2050/0013 Optimal controllers
• CPC Class Codes: B60W 30/188 Controlling power parameters of the driveline, e.g. determining the required power
• CPC Class Codes: Y02T 10/40 Engine management systems
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• CPC Class Codes: Y02T 10/84 Data processing systems or methods, management, administration

Abstract

Preferred operating points for a vehicle powertrain including an engine and a transmission are determined in accordance with a comprehensive operational mapping of input and output conditions and corresponding aggregate system losses corresponding to engine and transmission losses. In a hybrid transmission application, additional losses from motors and batteries are aggregated into the system losses and battery constraints are considered in determining preferred operating points.

Claims

1. Method for determining preferred input operating points for a vehicle powertrain system including an engine and a transmission comprising:

defining an output operating region of interest for the transmission;

defining an input operating region of interest for the transmission;

for points of operation within said output operating region of interest, determining preferred operating points within the input operating region as a function of preselected losses within the powertrain.

2. The method as claimed in claim 1 wherein said preselected losses are selected from the group consisting of engine losses and transmission losses and combinations thereof.

3. The method as claimed in claim 1 wherein said vehicle powertrain is a hybrid powertrain including an electric motor and battery, wherein said preselected losses are selected from the group consisting of engine losses, transmission losses, motor losses and battery losses and combinations thereof.

4. The method as claimed in claim 1 wherein said vehicle powertrain is a hybrid powertrain including an electric motor and battery, further comprising determining preferred operating points within the input operating region as a function of battery constraints.

5. The method as claimed in claim 4 wherein a first set of preferred operating points corresponding to unconstrained battery usage is determined and second set of preferred operating points corresponding to fully constrained battery usage is determined.

6. Method for determining preferred input operating points for a vehicle powertrain system including an engine and a transmission comprising:

defining an output operating region of interest for the transmission;

defining an input operating region of interest for the transmission;

mapping valid combinations of input operating points within said input operating region and output operating points within said output operating region to a measure of powertrain system losses at said valid combinations; and

,

for output operating points within said output operating region, selecting input operating points within said input operating region from mapped valid combinations corresponding to predetermined criteria.

7. The method as claimed in claim 6 wherein said vehicle powertrain is a hybrid powertrain including an electric motor and battery, wherein predetermined criteria are selected from the group consisting of powertrain losses and battery constraints and combinations thereof.

8. The method as claimed in claim 7 wherein said powertrain losses are selected from the group consisting of engine losses, transmission losses, motor losses and battery losses and combinations thereof.

9. The method as claimed in claim 7 wherein said battery constraints comprise no battery usage.

10. Method for determining preferred input operating points for a hybrid powertrain system including a hybrid transmission having an input coupled to an engine, an output, an electric motor and an electric battery comprising;

defining an operating space for the powertrain in transmission input speed (Ni), transmission input torque (Ti), transmission output speed (No), and transmission output torque (To);

determining aggregate powertrain system power losses throughout said operating space; and

,

determining at least one operating region in Ni, No, To corresponding to minimum aggregate system power losses wherein Ni within said determined operating region represents preferred input operating points.

11. The method as claimed in claim 10 wherein said transmission is a multi-mode transmission and said operating space is further defined in transmission modes.

12. The method as claimed in claim 10 wherein determining at least one operating region in Ni, No, To is performed for the entire operating space.

13. The method as claimed in claim 10 wherein determining at least one operating region in Ni, No, To is performed for a region within the operating space corresponding to system operation at zero battery power.

14. The method as claimed in claim 10 wherein determining at least one operating region in Ni, No, To is performed for the entire operating space and for a region within the operating space corresponding to system operation at zero battery power, wherein a pair of operating regions in Ni, No, To corresponding to unconstrained and fully constrained battery power is determined.

15. The method as claimed in claim 14 wherein said minimum aggregate system power losses are determined from a group of power losses consisting of engine losses, transmission losses, motor losses and battery losses and combinations thereof.