Fuel level measurement and run time interpolation

• US 20060090552A1
• Filed: 10/29/2004
• Published: 05/04/2006
• Est. Priority Date: 10/29/2004
• Status: Active Grant

• Current Assignee: American Power Conversion Corporation (Schneider Electric SE)
• Original Assignee: American Power Conversion Corporation (Schneider Electric SE)
• Inventors: Ziegler, William, Bennett, Craig L.
• Granted Patent: US 7,360,529 B2
• Time in Patent Office: Days
• US Class Current: 73/114.54
• CPC Class Codes: F02D 2200/0625 Fuel consumption, e.g. measured in fuel liters per 100 kms or miles per gallon
• CPC Class Codes: F02D 29/06 peculiar to engines driving electric generators
• CPC Class Codes: G01F 23/74 for sensing changes in level only at discrete points
• CPC Class Codes: G01F 9/008 where the other variable is the flight or running time
• CPC Class Codes: Y10T 137/7287 Liquid level responsive or maintaining systems

Abstract

At least one aspect of the invention provides an improved fuel sensing system for a generator, in addition, one or more other aspects of the invention provide improved systems and methods for determining remaining run-time of a generator system.

Claims

1. A generator system for providing power to a load, the generator system comprising;

a motor generator that generates output power to power the load;

a fuel tank operatively coupled to the motor generator to supply fuel to the motor generator; and

a fuel pickup and sensor assembly including;

a mounting device that couples to the fuel tank to mount the fuel pickup and sensor assembly on the fuel tank;

a fuel pickup tube coupled to the mounting device to support the fuel pickup tube in the fuel tank, wherein the fuel pickup tube includes an inlet to receive fuel from the fuel tank and an outlet to couple to the motor generator to provide fuel to the motor generator; and

a fuel sensor coupled to the mounting device, the fuel sensor having an output to provide an output level indicative of a level of fuel in the fuel tank.

2. The generator system of claim 1, wherein the fuel pickup tube is constructed and arranged such that a part of the fuel pickup tube contacts an inner bottom surface of the tank at a first location.

3. The generator system of claim 2, wherein the fuel sensor is constructed and arranged such that a part of the fuel sensor contacts the inner bottom surface of the tank at a second location.

4. The generator system of claim 3, wherein the first location is proximate the second location.

5. The generator system of claim 4, wherein the fuel pickup tube is constructed and arranged such that the inlet is at a predetermined height above the inner bottom surface of the tank.

6. The generator system of claim 5, wherein the fuel sensor includes a float that is moveable on the fuel sensor based on a level of fuel in the fuel tank.

7. The generator system of claim 1, further comprising a control system coupled to the motor generator to control the motor generator and coupled to the output of the fuel sensor to determine a level of fuel in the fuel tank.

8. The generator system of claim 7, wherein the control system is constructed and arranged to detect a minimum reading of the fuel sensor, and to determine a remaining run time of the generator system after the minimum reading has been reached.

9. The generator system of claim 8, wherein the control system is constructed and arranged to periodically update the remaining run time of the generator system.

10. The generator system of claim 9, wherein the control system is constructed and arranged to power the generator system down prior to a starvation point of the fuel pickup tube.

11. The generator system of claim 7, wherein the control system is constructed and arranged to determine a remaining run time of the generator system based on a quantity of power being supplied by the generator system and the level of fuel in the fuel tank.

12. The generator system of claim 11, wherein the fuel sensor is configured to provide output levels indicative of a plurality of fuel levels in the fuel tank including a first fuel level and a second fuel level, and wherein the control system is constructed and arranged to determine fuel levels in the fuel tank between the first fuel level and the second fuel level.

13. The generator system of claim 12, wherein the control system is constructed and arranged to detect a minimum reading of the fuel sensor, and to determine a remaining run time of the generator system after the minimum reading has been reached.

14. The generator system of claim 13, wherein the fuel pickup tube is constructed and arranged such that a part of the fuel pickup tube contacts an inner bottom surface of the tank at a first location.

15. The generator system of claim 14, wherein the fuel sensor is constructed and arranged such that a part of the fuel sensor contacts the inner bottom surface of the tank at a second location.

16. The generator system of claim 15, wherein the first location is proximate the second location.

17. The generator system of claim 16, wherein the fuel pickup tube is constructed and arranged such that the inlet is at a predetermined height above the inner bottom surface of the tank.

18. A method of monitoring fuel in a generator system having a fuel tank, the method comprising:

inserting a fuel pickup device and a fuel sensor through an opening in the fuel tank until a bottom end of each of the fuel pickup device and the fuel sensor contacts a bottom surface of the fuel tank; and

measuring a fuel level of the fuel tank using the fuel sensor.

19. The method of claim 18, further comprising detecting a minimum reading of the fuel sensor, and determining a remaining run time of the generator system after the minimum reading has been reached.

20. The method of claim 19, further comprising updating the remaining run time of the generator system.

21. The method of claim 20, further comprising powering down the generator system prior to a starvation point of the fuel pickup device being reached.

22. The method of claim 18, further comprising determining a remaining run time of the generator system based on a quantity of power being supplied by the generator system and a level of fuel in the fuel tank.

23. The method of claim 22, wherein the fuel sensor is configured to provide output levels indicative of a plurality of fuel levels in the fuel tank including a first fuel level and a second fuel level, and wherein the method further includes determining fuel levels in the fuel tank between the first fuel level and the second fuel level.

24. The method of claim 23, further comprising detecting a minimum reading of the fuel sensor, and determining a remaining run time of the generator system after the minimum reading has been reached.

25. A generator system for providing power to a load, the generator system comprising;

a motor generator that generates output power to power the load;

a fuel tank coupled to the motor generator to supply fuel to the motor generator;

a fuel pickup and sensor assembly including;

an inlet to receive fuel from the fuel tank and an outlet to couple to the motor generator to provide fuel to the motor generator;

a fuel sensor having an output to provide an output level indicative of a level of fuel in the fuel tank; and

means for maintaining a fixed vertical distance between the inlet and a lowest reading position of the fuel sensor.

26. The generator system of claim 25, further comprising means coupled to the output of the fuel sensor for determining a level of fuel in the fuel tank.

27. The generator system of claim 26, further comprising means for detecting a minimum reading of the fuel sensor, and for determining a remaining run time of the generator system after the minimum reading has been reached.

28. The generator system of claim 27, further comprising means for updating the remaining run time of the generator system.

29. The generator system of claim 28, further comprising means for powering down the generator system prior to a starvation point of the fuel pickup and sensor assembly.

30. The generator system of claim 25, further comprising means for determining a remaining run time of the generator system based on a quantity of power being supplied by the generator system and a level of fuel in the fuel tank.

31. The generator system of claim 30, wherein the fuel sensor is configured to provide output levels indicative of a plurality of fuel levels in the fuel tank including a first fuel level and a second fuel level, and wherein the generator system further comprises means for determining fuel levels in the fuel tank between the first fuel level and the second fuel level.

32. The generator system of claim 31, further comprising means for detecting a minimum reading of the fuel sensor, and for determining a remaining run time of the generator system after the minimum reading has been reached.

33. A control system for a generator system having a fuel tank with a fuel sensor having an output that provides an indication of a level of fuel in the fuel tank including a first fuel level and a second fuel level, the control system comprising:

a first input to couple to the output of the fuel sensor; and

a second input to receive at least one signal indicative of a power output level of the generator system;

wherein the control system is constructed and arranged to determine fuel levels in the fuel tank between the first level and the second level.

34. The control system of claim 33, wherein the control system is constructed and arranged to determine a remaining run time of the generator system.

35. The control system of claim 34, wherein the control system is constructed and arranged to detect a minimum reading of the fuel sensor, and to determine a remaining run time of the generator system after the minimum reading has been reached.

36. The control system of claim 35, wherein the control system is constructed and arranged to update the remaining run time of the generator system.

37. A control system for a generator system having a fuel tank with a fuel sensor having an output that provides an indication of a level of fuel in the fuel tank including a first fuel level and a second fuel level, the control system comprising:

a first input coupled to the output of the fuel sensor;

a second input to receive at least one signal indicative of a power output level of the generator system; and

means for determining fuel levels in the fuel tank between the first fuel level and the second fuel level.

38. The control system of claim 37, further comprising means for determining a remaining run time of the generator system.

39. The control system of claim 38, further comprising means for detecting a minimum reading of the fuel sensor, and for determining a remaining run time of the generator system after the minimum reading has been reached.

40. The control system of claim 39, further comprising means for updating the remaining run time of the generator system.

41. A method for controlling a generator system having a fuel tank with a fuel sensor having an output that provides an indication of a level of fuel in the fuel tank including a first fuel level and a second fuel level, the method comprising:

receiving an indication of the first fuel level in the tank from the fuel sensor;

receiving an indication of an output power level of the generator system; and

determining fuel levels in the fuel tank between the first fuel level and the second fuel level.

42. The method of claim 41, further comprising determining a remaining run time of the generator system.

43. The method of claim 42, further comprising detecting a minimum reading of the fuel sensor, and determining a remaining run time of the generator system after the minimum reading has been reached.

44. The method of claim 43, further comprising updating the remaining run time of the generator system.