Method and apparatus for adaptively controlling a state of charge of a battery array of a series type hybrid electric vehicle

• US 6,333,620 B1
• Filed: 09/15/2000
• Issued: 12/25/2001
• Est. Priority Date: 09/15/2000
• Status: Expired due to Term

• Current Assignee: Wonderland Investment Group Inc
• Original Assignee: Transportation Technologies, LLC
• Inventors: Schmitz, Robert W., Anderson, Joshua J., Wilton, Thomas F.
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US09/663,118
• Time in Patent Office: 466 Days
• Field of Search: 320/103, 320/104, 320/132, 429/61, 429/90, 340/635, 340/636
• US Class Current: 320/132
• CPC Class Codes: B60L 2200/18 Buses
• CPC Class Codes: B60L 2220/12 Induction machines
• CPC Class Codes: B60L 2220/14 Synchronous machines
• CPC Class Codes: B60L 2220/16 DC brushless machines
• CPC Class Codes: B60L 2240/445 Temperature
• CPC Class Codes: B60L 2250/10 by alarm
• CPC Class Codes: B60L 50/61 by batteries charged by engine-driven generators, e.g. series hybrid electric vehicles
• CPC Class Codes: B60L 58/15 Preventing overcharging
• CPC Class Codes: H01M 10/482 for several batteries or cells simultaneously or sequentially
• CPC Class Codes: Y02E 60/10 Energy storage using batteries
• CPC Class Codes: Y02T 10/62 Hybrid vehicles
• 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
• CPC Class Codes: Y02T 10/72 Electric energy management in electromobility

Abstract

A series type hybrid electric vehicle including a generator set having an internal combustion engine and a generator, a battery array and at least one electric motor includes a controller for maintaining a state of charge of the battery array within a control limit. A controller of the vehicle determines if the vehicle is in one of a plurality of forward driving modes, compares a state of charge of the battery array to an upper control limit associated with a forward driving mode, decreases generated by the generator, if the state of charge is equal to or greater than the associated upper control limit, and increases the power generated by the generator, if the state of charge is less than the associated upper control limit. A method of controlling the state of charge of the battery array includes determining if the vehicle is in one of a plurality of forward driving modes, comparing a state of charge of the battery array to an upper control limit associated with a forward driving mode, decreasing the power generatred by the generator, if the state of charge is equal to or greater than the associated upper control limit, and increasing the power generated by the generator, if the state of charge is less than the associated upper control limit.

Claims

1. A method for adaptively controlling a state of charge of a battery array of a series type hybrid electric vehicle including an internal combustion engine connected to a generator and at least one electric motor, comprising:

determining if the vehicle is in one of a plurality of forward driving modes;

comparing a state of charge of the battery array to an upper control limit associated with a forward driving mode;

decreasing the power generated by the generator, if the state of charge is equal to or greater than the associated upper control limit; and

increasing the power generated by the generator, if the state of charge is less than the associated upper control limit.

2. The method of claim 1, further comprising:

determining if a differential between a load on the generator and the power generated by the generator is larger than a predetermined differential associated with a forward driving mode, if the state of charge is equal to or greater than the associated upper control limit; and

at least one of decreasing a speed of the engine and increasing the power generated by the generator, if the differential is larger than the predetermined differential.

3. The method of claim 1, further comprising:

determining if a heat output of the engine is larger than a predetermined heat output associated with the forward driving mode, if the state of charge is equal to or greater than the associated upper control limit;

determining if a speed of the engine is at a maximum, if the heat output is not larger than the predetermined heat output; and

increasing the speed of the engine, if the speed of the engine is not at the maximum.

4. The method of claim 3, further comprising:

disabling the generator, if the heat output of the engine is larger than the predetermined heat output.

5. The method of claim 1, further comprising:

comparing an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

increasing a speed of the engine, if the intermediate state of charge is less than the associated upper control limit.

6. The method of claim 5, further comprising:

maintaining the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

7. The method of claim 1, further comprising:

comparing an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

decreasing a peak power output of the at least one electric motor, if the intermediate state of charge is less than the associated upper control limit.

8. The method of claim 7, further comprising:

maintaining the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

9. The method of claim 1, further comprising:

comparing an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

shedding power from the vehicle, if the intermediate state of charge is less than the associated upper control limit.

10. The method of claim 9, further comprising:

maintaining the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

11. The method of claim 1, further comprising:

comparing an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

issuing a warning, if the intermediate state of charge is less than the associated upper control limit.

12. The method of claim 11, further comprising:

maintaining the generator at a maximum level.

13. The method of claim 1, further comprising:

desulfating and equalizing the battery array, if the vehicle is not in a forward driving mode.

14. The method of claim 1, wherein the state of charge is an initial state of charge.

15. A series type hybrid electric vehicle, comprising:

an internal combustion engine connected to a generator;

a battery array receiving current at least from the generator;

at least one electric motor receiving current from the battery array; and

a controller that;

determines if the vehicle is in one of a plurality of forward driving modes;

compares a state of charge of the battery array to an upper control limit associated with a forward driving mode;

decreases the power generated by the generator, if the state of charge is equal to or greater than the associated upper control limit; and

increases the power generated by the generator, if the state of charge is less than the associated upper control limit.

16. The vehicle of claim 15, wherein the controller:

determines if a differential between a load on the generator and the power generated by the generator is larger than a predetermined differential associated with a forward driving mode, if the state of charge is equal to or greater than the associated upper control limit; and

at least one of decreases a speed of the engine and increases the power generated by the generator, if the differential is larger than the predetermined differential.

17. The vehicle of claim 15, wherein the controller:

determines if a heat output of the engine is larger than a predetermined heat output associated with the forward driving mode, if the state of charge is equal to or greater than the associated upper control limit;

determines if a speed of the engine is at a maximum, if the heat output is not larger than the predetermined heat output; and

increases the speed of the engine, if the speed of the engine is not at the maximum.

18. The vehicle of claim 17, wherein the controller:

disables the generator, if the heat output of the engine is larger than the predetermined heat output.

19. The vehicle of claim 15, wherein the controller:

compares an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

increases a speed of the engine, if the intermediate state of charge is less than the associated upper control limit.

20. The vehicle of claim 19, wherein the controller:

maintains the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

21. The vehicle of claim 15, wherein the controller:

compares an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

decreases a peak power output of the at least one electric motor, if the intermediate state of charge is less than the associated upper control limit.

22. The vehicle of claim 21, wherein the controller:

maintains the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

23. The vehicle of claim 15, wherein the controller:

compares an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

sheds power from the vehicle, if the intermediate state of charge is less than the associated upper control limit.

24. The vehicle of claim 23, wherein the controller:

maintains the generator at a maximum level, if the intermediate state of charge is equal to or larger than the associated upper control limit.

25. The vehicle of claim 15, wherein the controller:

compares an intermediate state of charge to the associated upper control limit after increasing the power generated by the generator when the state of charge is less than the associated upper control limit; and

issues a warning, if the intermediate state of charge is less than the associated upper control limit.

26. The vehicle of claim 25, wherein the controller:

maintains the generator at a maximum level.

27. The vehicle of claim 15, wherein the controller:

desulfates and equalizes the battery array, if the vehicle is not in a forward driving mode.

28. The vehicle of claim 15, wherein the state of charge is an initial state of charge.

29. The vehicle of claim 15, wherein a performance enhancement factor is at least 6.2.