System for controlling a hybrid energy system

• US 20080179891A1
• Filed: 01/31/2007
• Published: 07/31/2008
• Est. Priority Date: 01/31/2007
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Lane, William H.
• Granted Patent: US 7,436,081 B2
• Time in Patent Office: Days
• US Class Current: 290/40C
• CPC Class Codes: B60L 2200/26 Rail vehicles
• CPC Class Codes: B60L 50/10 using propulsion power supplied by engine-driven generators, e.g. generators driven by combustion engines
• CPC Class Codes: B60L 58/10 for monitoring or controlling batteries
• CPC Class Codes: Y02T 10/70 Energy storage systems for electromobility, e.g. batteries
• CPC Class Codes: Y02T 10/7072 Electromobility specific charging systems or methods for batteries, ultracapacitors, supercapacitors or double-layer capacitors

Abstract

A method and apparatus are disclosed for controlling a hybrid energy system including at least an energy source having a maximum energy output and an energy storage device. The method includes determining a first amount of energy indicative of an amount of energy associated with the current operating condition of the energy source and determining a second amount of energy indicative of energy associated with the energy storage device. The method also includes estimating a third amount of energy indicative of a difference between the first amount of energy and the maximum energy output. The method further includes controlling the energy source as a function of the second and third amounts of energy.

Claims

1. A method for controlling a hybrid energy system including at least an energy source having a maximum energy output and a energy storage device, the method comprising:

determining a first amount of energy indicative of an amount of energy associated with the current operating condition of the energy source;

determining a second amount of energy indicative of energy associated with the energy storage device;

estimating a third amount of energy indicative of a difference between the first amount of energy and the maximum energy output; and

controlling the energy source as a function of the second and third amounts of energy.

2. The method of claim 1, further including controlling the energy source to another operating condition having an amount of energy greater than the first amount of energy if the second amount of energy is not within a predetermined range.

3. The method of claim 1, further including controlling the energy source to another operating condition having an amount of energy greater than the first amount of energy if the second amount of energy is less than the third amount of energy.

4. The method of claim 3, further including:

comparing the second amount of energy with a predetermined range;

comparing the second amount of energy with the third amount of energy; and

subsequently determining if the current operating condition is at a desired operating condition if the second amount of energy is within the predetermined range and greater than the third amount of energy.

5. The method of claim 4, further including controlling the power source to another operating condition if the current operating condition is not a desired operating condition.

6. The method of claim 1, wherein the hybrid energy system further includes a controller configured to determine the first, second, and third amounts of energy and affect control of the energy source.

7. A hybrid energy system comprising:

a first source of energy configured to output a variable amount of first energy between a maximum energy and a minimum energy;

a second source of energy configured to store a variable amount of second energy; and

a controller configured to;

estimate a first value indicative of a difference between the first energy and the maximum energy,

determine a second value indicative of the second energy, and

affect control of the first source to selectively change the first energy as a function of the first value and the second value.

8. The system of claim 7, further including a load operatively connected to the first and second sources and configured to selectively receive energy from each of the first and second sources.

9. The system of claim 7, further including:

at least one first sensor configured to produce at least one first signal indicative of at least one operating parameter of the first source; and

at least one second sensor configured to produce at least one second signal indicative of at least one operating parameter of the second source.

10. The system of claim 7, wherein the controller is further configured to increase the amount of first energy if the amount of second energy is less than a predetermined value.

11. The system of claim 7, wherein the controller is further configured to increase the amount of first energy if the amount of second energy is less than the first value.

12. The system of claim 7, wherein the controller is further configured to determine if the first source is operating at a desired operating condition if the amount of first energy is greater than a predetermined value and greater than the first value.

13. The system of claim 12, wherein the controller is further configured to control the first source to another operating condition if the first source is not operating at a desired operating condition.

14. The system of claim 12, wherein determining if the first source is operating at a desired operating condition includes determining whether the first source is operating within a predetermined range of emission production values.

15. The system of claim 12, wherein determining if the first source is operating at a desired operating condition includes determining whether the first source is operating within a predetermined range of fuel consumption values.

16. A method of controlling a hybrid energy system having an engine and an energy storage device, comprising:

determining a first amount of energy associated with the engine;

estimating a second amount of energy indicative of a difference between the first amount of energy and a predetermined amount of energy;

determining a third amount of energy associated with the energy storage device; and

controlling the operation of the engine as a function of the second and third amounts of energy.

17. The method of claim 16, wherein:

the first amount of energy is indicative of an amount of energy output by the engine at a current operating condition; and

controlling the operation of the engine further includes affecting the engine to operate at another operating condition having an increased energy output with respect to the current operating condition when the third amount of energy is less than a predetermined value.

18. The method of claim 16, wherein:

the first amount of energy is indicative of an amount of energy output by the engine at a current operating condition; and

controlling the operation of the engine further includes affecting the engine to operate at another operating condition having an increased energy output with respect to the current operating condition when the third amount of energy is less than the second amount of energy.

19. The method of claim 16, wherein:

the first amount of energy is indicative of an amount of energy output by the engine at a current operating condition; and

controlling the operation of the engine further includes determining if the current operating condition is a desired engine operating condition.

20. The method of claim 19, wherein:

the desired operating condition is indicative of an engine operating condition producing a desired amount of emissions; and

controlling the operation of the engine further includes affecting the engine to operate at another operating condition producing a lower amount emissions with respect to the current operating condition when the current operating condition is not a desired engine operating condition.