Forward-looking hybrid vehicle control strategy

• US 8,565,952 B2
• Filed: 05/20/2011
• Issued: 10/22/2013
• Est. Priority Date: 05/20/2011
• Status: Expired due to Fees

• Current Assignee: GM Global Technology Operations LLC (General Motors Company)
• Original Assignee: GM Global Technology Operations LLC (General Motors Company)
• Inventors: Mehr, Daniel K., Simonini, Matthew, Lombardo, Paul S., Haliburton, Christopher M.
• Primary Examiner(s): Tarcza, Thomas
• Assistant Examiner(s): Lee, Tyler J
• Application Number:
  US13/112,008
• Publication Number:
  US 20120296502A1
• Time in Patent Office: 886 Days
• Field of Search: 701/22, 701/119, 701/532, 180 651- 658
• US Class Current: 701/22
• CPC Class Codes: B60K 6/48 Parallel type
• CPC Class Codes: B60L 50/00 Electric propulsion with power supplied within the vehicle with power supply from force of nature, e.g. sun or wind, B60L8/00; for monorail vehicles, suspension vehicles or rack railways B60L13/00
• 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 10/24 including control of energy storage means
• 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 20/12 using control strategies taking into account route information estimation or calculation of non-directly measurable driving parameters B60W40/00
• CPC Class Codes: B60W 2510/244 Charge state
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2552/20 Road profile, i.e. the change in elevation or curvature of a plurality of continuous road segments
• CPC Class Codes: B60W 2552/40 Coefficient of friction
• CPC Class Codes: B60W 2555/60 Traffic rules, e.g. speed limits or right of way
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: B60W 2710/244 Charge state
• CPC Class Codes: B60W 50/0097 Predicting future conditions
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A vehicle includes an engine, a power source, and a motor. The power source outputs electrical energy in accordance with an actual state of charge, and the motor generates electrical energy when provided with torque from the engine. A position sensor generates a route signal representing drive cycle data between a present location of the vehicle and a selected destination. A controller determines a reference state of charge of the power source at the present location from the drive cycle data and commands the engine to charge the power source if the actual state of charge is below the reference state of charge determined for the present location. A method includes receiving the selected destination, generating the route signal, determining the reference state of charge from the drive cycle data, and commanding the engine to charge the power source in accordance with the reference state of charge.

Claims

1. A vehicle comprising:

an engine configured to generate an engine torque;

a power source configured to output electrical energy in accordance with an actual state of charge;

a motor selectively coupled to the engine and configured to receive electrical energy from the power source, generate a motor torque in accordance with the electrical energy received, and generate electrical energy when provided with the engine torque;

a position sensor configured to generate a route from a present location of the vehicle to a selected destination, and generate a route signal representing drive cycle data for the route, wherein the drive cycle data includes speed limits at various locations along the route, rolling resistances at various locations along the route, and road grades at various locations along the route; and

a controller in communication with the position sensor and configured to receive the route signal generated by the position sensor and representing the drive cycle data of the route, determine a reference state of charge of the power source at the present location from the drive cycle data, and command the engine to charge the power source if the actual state of charge is below the reference state of charge determined for the present location;

wherein the controller is operable to determine the reference state of charge from a ratio of an accumulated load energy relative to a total load energy; and

wherein the controller is operable to predict the total load energy and determine the accumulated load energy from the following equation using the drive cycle data;

2. The vehicle as set forth in claim 1, further comprising a clutch operably disposed between the engine and the motor to selectively couple the engine to the motor.

3. The vehicle as set forth in claim 1, wherein the reference state of charge includes a maximum state of charge and a minimum state of charge, and wherein the controller is configured to enable the engine to charge the power source if the actual state of charge is below the minimum state of charge.

4. The vehicle as set forth in claim 3, wherein the controller is configured to command the engine to stop charging the power source if the actual state of charge is substantially equal to or greater than the maximum state of charge.

5. The vehicle as set forth in claim 1, wherein the position sensor includes a user interface configured to receive a selection from a user.

6. The vehicle as set forth in claim 5, wherein the user interface is configured to present the user with a prompt to select a destination, and wherein the position sensor is configured to generate the route signal in accordance with the destination selected by the user.

7. The vehicle as set forth in claim 1, wherein the position sensor is configured to determine the present location.

8. The vehicle as set forth in claim 1, wherein the drive cycle data includes one or more of a speed limit, a road grade, and a rolling resistance.

15. A vehicle as set forth in claim 1 wherein the controller is operable to calculate the reference state of charge from the following equation:

9. A method of controlling an engine to charge a power source in a hybrid vehicle, the method comprising:

receiving, via a user interface, a selected destination for the hybrid vehicle;

generating a route signal representing drive cycle data between a present location of the hybrid vehicle and the selected destination, wherein the drive cycle data includes speed limits at various locations along the route, rolling resistances at various locations along the route, and road grades at various locations along the route;

determining a reference state of charge for the present location from the drive cycle data from a ratio of an accumulated load energy relative to a total load energy, wherein the total load energy and the accumulated load energy are calculated from the following equation using the drive cycle data;

10. The method as set forth in claim 9, wherein the power source is configured to output electrical energy in accordance with an actual state of charge and wherein the reference state of charge includes a maximum state of charge and a minimum state of charge;

and

wherein commanding the engine to charge the power source in accordance with the reference state of charge includes commanding the engine to charge the power source if the actual state of charge is below the minimum state of charge.

11. The method as set forth in claim 10, wherein commanding the engine to charge the power source in accordance with the reference state of charge includes commanding the engine to stop charging the power source if the actual state of charge is substantially equal to or greater than the maximum state of charge.

12. The method as set forth in claim 9, further comprising determining the present location of the hybrid vehicle via a position sensor.

13. The method as set forth in claim 9, wherein determining the reference state of charge for the present location from the drive cycle data includes determining the reference state of charge for the present location based at least in part on one or more of a speed limit, a road grade, and a rolling resistance of the present location.

16. A method as set forth in claim 9 further comprising calculating the reference state of charge from the following equation:

14. A vehicle comprising:

an engine configured to generate an engine torque;

a power source configured to output electrical energy in accordance with an actual state of charge;

a motor selectively coupled to the engine and configured to receive electrical energy from the power source, generate a motor torque in accordance with the electrical energy received, and generate electrical energy when coupled to the engine, wherein the motor is selectively coupled to the engine to receive the engine torque and generate electrical energy in accordance with the engine torque received;

a position sensor having a user interface and configured to prompt a user to select a destination, determine a present location, generate a route signal representing drive cycle data between the present location of the vehicle and a selected destination, wherein the drive cycle data includes at least one of a speed limit, a road grade, and a rolling resistance at the present location; and

a controller in communication with the position sensor and configured to receive the route signal and determine a reference state of charge of the power source at the present location based at least in part on a ratio of an accumulated load energy determined from the drive cycle data and a total load energy determined from the drive cycle data, wherein the reference state of charge is defined by at least one of a maximum state of charge and a minimum state of charge;

wherein the controller is operable to predict the total load energy and determine the accumulated load energy from the following equation using the drive cycle data;

17. A vehicle as set forth in claim 14 wherein the controller is operable to calculate the reference state of charge from the following equation: