Adaptive power system

• US 7,385,374 B2
• Filed: 05/25/2004
• Issued: 06/10/2008
• Est. Priority Date: 05/27/2003
• Status: Expired due to Fees

• Current Assignee: Rice University
• Original Assignee: Rice University
• Inventors: Ganier, Carroll J. II, Frantz, Jeremy P., Welsh, Erik J.
• Primary Examiner(s): Berhane; Adolf
• Assistant Examiner(s): Berhanu; Samuel
• Application Number:
  US10/853,862
• Publication Number:
  US 20040257047A1
• Time in Patent Office: 1,477 Days
• Field of Search: 320/101, 320/102, 320/103, 320/138, 307/66, 307/43
• US Class Current: 320/138
• CPC Class Codes: H02J 7/0013 acting upon several batteries simultaneously or sequentially H02J7/1423 takes precedence

Abstract

A power system having an extended life and a system and method for extending the life of a battery powered device. In one embodiment, the method comprises providing a plurality of power sources and an alternate energy source. The method also comprises measuring the voltage of the power sources and the alternate energy source. The method further comprises selecting a power source to provide voltage to the device, wherein the selected power source provides voltage to the device. In addition, the method comprises optionally charging any power source that is providing voltage to the device. Moreover, the method is repeated after a variable delay. Further embodiments include switching to providing the voltage to the device from a power source while charging another power source.

Claims

1. A system for extending a device life, comprising:

a plurality of power sources, wherein each power source is disposed to be charged when one of the power sources is providing voltage to the device;

an alternate energy source, wherein the alternate energy source is disposed to charge power sources that are not providing voltage to the device; and

(i) reads the voltages of the power sources and the alternate energy source,

(ii) saves the measured voltages of the power sources and the alternate energy source in a saved voltage data history,

(iii) selects a variable time delay based on the saved voltage data history, and

(iv) repeats (i)-(iii) after the variable time delay.

2. The system of claim 1, wherein the power sources are batteries.

3. The system of claim 1, wherein the processing device determines which power source provides the voltage to the device.

4. The system of claim 3, wherein the processing device determines whether a power source is to be charged.

5. The system of claim 1, wherein the alternate energy source charges the power sources that are not providing voltage to the device.

6. The system of claim 1, wherein the alternate energy source provides voltage to the device.

7. The system of claim 1, wherein the alternate energy source does not charge the plurality of power sources.

8. The system of claim 1, wherein the processing device comprises a microcontroller, a programmable logic device, a field programmable gate array, or a general purpose processor.

9. A method for extending a device life, comprising:

(A) providing a plurality of power sources and an alternate energy source;

(B) measuring the voltages of the power sources and the alternate energy source;

(C) saving the measured voltages of the power sources and the alternate energy source in a saved voltage data history and selecting a variable time delay based on the saved voltage data history;

(D) selecting a power source to provide voltage to the device, wherein the selected power source provides voltage to the device;

(E) charging any power source that is not providing voltage to the device in step (D); and

(F) repeating steps (B)-(E) after the variable time delay.

10. The method of claim 9, wherein the power sources are batteries.

11. The method of claim 9, wherein step (D) further comprises comparing the voltage of a first power source to a first power source minimum threshold voltage.

12. The method of claim 11, wherein the first power source provides the voltage to the device when the voltage of the first power source is greater than the first power source minimum threshold voltage.

13. The method of claim 12, wherein the voltage of the alternate energy source is compared to an alternate energy minimum threshold voltage.

14. The method of claim 13, wherein the alternate energy source charges the any power source that is not providing voltage to the device when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

15. The method of claim 13, wherein the alternate energy source does not charge the any power source that is not providing voltage to the device when the voltage of the alternate energy source is not greater than the alternate energy minimum threshold voltage.

16. The method of claim 11, wherein the any power source that is not providing voltage to the device comprises a second power source, wherein the voltage of the second power source is compared to a second power source minimum threshold voltage when the voltage of the first power source is less than the first power source minimum threshold voltage.

17. The method of claim 16, wherein the second power source provides the voltage to the device when the voltage of the second power source is not less than a second power source minimum threshold voltage.

18. The method of claim 17, wherein the voltage of the alternate energy source is compared to an alternate energy minimum threshold voltage.

19. The method of claim 18, wherein the alternate energy source charges the first power source in step (E) when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

20. The method of claim 18, wherein the first power source is not charged by the alternate energy source when the voltage of the alternate energy source is not greater than the alternate energy minimum threshold voltage.

21. The method of claim 16, wherein a low power mode is selected for the device when no power source has a voltage greater than a minimum threshold voltage.

22. The method of claim 21, wherein the voltage of the alternate energy source is compared to an alternate energy minimum threshold voltage.

23. The method of claim 22, wherein the alternate energy source charges the plurality of power sources in step (B) when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

24. The method of claim 9, wherein the alternate energy source provides voltage to the device.

25. A method for extending a device life, comprising:

(A) providing a plurality of power sources and an alternate energy source, wherein the plurality of power sources are capable of being charged, wherein each power source has a respective power source minimum threshold voltage;

(B) measuring the voltage of the plurality of power sources and the alternate energy source;

(C) saving the measured voltages of the power sources and the alternate energy source in a saved voltage data history and selecting a variable time delay based on the saved voltage data history;

(D) comparing the voltage of a first power source to a first power source minimum threshold voltage, wherein the plurality of power sources includes the first power source;

(E) comparing the voltage of at least one other power source to at least one power source minimum threshold voltage;

(F) comparing the voltage of the alternate energy source to an alternate energy minimum threshold voltage;

(G) selecting a low power mode for the device if the voltage of each power source is less than each respective power source minimum threshold voltage; and

(H) repeating steps (B)-(G) after the variable time delay.

26. The method of claim 25, wherein the power sources are batteries.

27. The method of claim 25, wherein step (D) further comprises the first power source providing voltage to the device when the voltage of the first power source is not less than the first power source minimum threshold voltage.

28. The method of claim 27, wherein the voltage of the alternate energy source is compared to an alternate energy minimum threshold voltage after step (D).

29. The method of claim 25, wherein the alternate energy source charges the at least one other power source when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

30. The method of claim 28, wherein the at least one other power source is not charged by the alternate energy source when the voltage of the alternate energy source is less than the alternate energy minimum threshold voltage.

31. The method of claim 25, wherein step (B) is accomplished when the voltage of the first power source is less than the first power source minimum threshold voltage.

32. The method of claim 31, wherein at least one of the at least one other power source provides voltage to the device when the voltage of the at least one of the at least one other power source is greater than a power source minimum threshold voltage.

33. The method of claim 32, wherein the voltage of The alternate energy source is compared to an alternate energy minimum threshold voltage.

34. The method of claim 33, wherein the alternate energy source charges the first power source when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

35. The method of claim 33, wherein the first power source is not charged by the alternate energy source when the voltage of the alternate energy source is less than the alternate energy minimum threshold voltage.

36. The method of claim 25, step (G) further comprises comparing the voltage of the alternate energy source to an alternate energy minimum threshold voltage.

37. The method of claim 25, wherein the voltage of the alternate energy source is compared to an alternate energy minimum threshold voltage when the low power mode of step (G) is selected.

38. The method of claim 37, wherein the alternate energy source charges the plurality of power sources when the voltage of the alternate energy source is greater than the alternate energy minimum threshold voltage.

39. The method of claim 25, wherein the alternate energy source provides voltage to the device.