Machine with an electrical system

• US 20070210582A1
• Filed: 08/30/2005
• Published: 09/13/2007
• Est. Priority Date: 08/30/2005
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Bernardi, John, Morrical, Brian, Goldammer, Timothy
• Granted Patent: US 7,291,934 B2
• Time in Patent Office: Days
• US Class Current: 290/46
• CPC Class Codes: B60K 6/46 Series type
• 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 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/10 Controlling the power contribution of each of the prime movers to meet required power demand
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A machine includes an electrical power source, which may include a mechanical power source and an electric generator drivingly connected to the mechanical power source. The machine may also include one or more power loads connected to the electric generator. Additionally, the machine may include power-supply controls, which may be configured to execute a control method. The control method may include receiving inputs relating to conditions of operation of the machine. Additionally, the control method may include controlling the speed at which the mechanical power source drives the electric generator, and the power consumption of one or more of the power loads connected to the electric generator, interdependently.

Claims

1. A machine, including:

an electrical power source, including a mechanical power source and an electric generator drivingly connected to the mechanical power source;

one or more power loads connected to the electric generator; and

power-supply controls configured to execute a control method, including;

receiving inputs relating to conditions of operation of the machine; and

controlling the speed at which the mechanical power source drives the electric generator, and the power consumption of one or more of the power loads connected to the electric generator, interdependently.

2. The machine of claim 1, wherein the control method includes:

causing the mechanical power source to drive the electric generator at a first speed under a first set of conditions, including an estimated power need of a set of one or more of the power loads connected to the electric generator being below a first amount of power; and

causing the mechanical power source to drive the electric generator at a second speed, higher than the first speed, under a second set of conditions, including the estimated power need of the set of one or more of the power loads connected to the electric generator being above the first amount of power.

3. The machine of claim 2, wherein the control method further includes:

while causing the mechanical power source to drive the electric generator at the second speed, if the estimated power need of the set of one or more of the power loads connected to the electric generator exceeds a second amount of power, higher than the first amount of power, limiting the amount of power consumed by the set of one or more of the power loads connected to the electric generator to the second amount of power.

4. The machine of claim 3, wherein the second amount of power is substantially equal to the power capacity of the electrical power source with the mechanical power source driving the electric generator at the second speed.

5. The machine of claim 2, wherein the control method includes:

in response to the estimated power need of the set of one or more of the power loads connected to the electric generator increasing from below the first amount of power to above the first amount of power, increasing the speed at which the mechanical power source drives the electric generator from the first speed to the second speed; and

subsequently, maintaining the speed at which the mechanical power source drives the electric generator at the second speed for at least a predetermined delay period.

6. The machine of claim 2, wherein the first set of conditions includes the mechanical power source having operated for at least a predetermined period.

7. The machine of claim 1, wherein the control method includes:

in response to an increase in an estimated power need of one or more of the power loads connected to the electric generator;

adjusting controls of the mechanical power source to increase its operating speed; and

during a transition period following the adjustment of the controls of the mechanical power source to increase its operating speed, controlling the amount of power consumed by one or more of the power loads to avoid overwhelming the electrical power source.

8. The machine of claim 1, wherein:

the electric generator is an alternating current generator; and

power produced by the electric generator is converted from alternating current to direct current before being delivered to the power loads connected to the electric generator.

9. The machine of claim 1, further including:

a propulsion system, including;

a prime mover; and

one or more propulsion devices drivingly connected to the prime mover.

10. The machine of claim 9, wherein the electrical power source is an auxiliary power unit.

11. The machine of claim 10, wherein the mechanical power source is a prime mover.

12. The machine of claim 1, wherein controlling the speed at which the mechanical power source drives the electric generator includes adjusting controls of the mechanical power source to control the speed at which the mechanical power source operates.

13. A machine, including:

an electrical power source, including a mechanical power source and an electric generator drivingly connected to the mechanical power source;

one or more power loads connected to the electric generator; and

power-supply controls configured to execute a control method, including;

receiving inputs relating to conditions of operation of the machine;

adjusting controls of the mechanical power source to increase the operating speed of the mechanical power source from a first speed; and

during a transition period following the adjustment of the controls of the mechanical power source to increase its operating speed, controlling the amount of power consumed by one or more of the power loads to avoid overwhelming the electrical power source.

14. The machine of claim 13, wherein adjusting the controls of the mechanical power source to increase its operating speed from the first speed is done in response to inputs indicating that an estimated power need of one or more of the power loads connected to the electric generator has exceeded a predetermined amount of power.

15. The machine of claim 14, wherein controlling the power consumption of the power loads to avoid overwhelming the electrical power source includes:

in response to inputs indicating that the power loads connected to the electric generator may be overwhelming the electrical power source, suppressing the amount of power consumed by one or more of the power loads.

16. The machine of claim 15, wherein:

one or more of the power loads are connected to the first electric generator by a power-transmission system; and

wherein inputs indicating that the power loads may be overwhelming the electrical power source include inputs relating to a state of electrification of the power-transmission system.

17. The machine of claim 14, wherein the control method further includes:

subsequent to adjusting the controls of the mechanical power source to increase the operating speed of the mechanical power source from the first speed, causing the controls of the mechanical power source to maintain its operating speed at a second speed for at least a predetermined delay period.

18. The machine of claim 13, wherein:

adjusting the controls of the mechanical power source to increase its operating speed from the first speed includes adjusting the controls of the mechanical power source to increase its operating speed from the first speed to a predetermined second speed; and

the control method further includes;

subsequent to adjusting the controls of the mechanical power source to increase its operating speed from the first speed to the second speed, causing the controls of the mechanical power source to maintain its operating speed at the second speed for at least a predetermined delay period.

19. The machine of claim 13, wherein controlling the power consumption of the power loads to avoid overwhelming the electrical power source includes:

in response to inputs indicating that the power loads may be overwhelming the electrical power source, suppressing the amount of power consumed by one or more of the power loads.

20. The machine of claim 19, wherein:

one or more of the power loads are connected to the electric generator through a first portion of a distribution network;

one or more of the power loads are connected to the electric generator through a second portion of the distribution network;

the power-supply controls are capable of automatically controlling whether power is supplied to the first portion of the distribution network, but incapable of individualized, automatic control of the amount of power supplied to one or more of the power loads connected to the electric generator through the first portion of the distribution network; and

suppressing the amount of power consumed by the power loads in response to inputs indicating that the power loads may be overwhelming the electrical power source during the transition period includes temporarily preventing supply of power to the first portion of the distribution network.

21. The machine of claim 19, wherein:

the power loads are connected to the electric generator through a power-transmission system; and

inputs indicating that the power loads may be overwhelming the electrical power source include inputs relating to the state of electrification of the power-transmission system.

22. The machine of claim 19, wherein:

the power loads are connected to the electric generator through a power-transmission system; and

inputs indicating that the power loads may be overwhelming the electrical power source include inputs indicating that a voltage level in a portion of the power-transmission system is below a predetermined level.

23. The machine of claim 13, wherein the electrical power source is an auxiliary mechanical power source.

24. The machine of claim 13, wherein the mechanical power source is a prime mover.

25. A machine, including:

a mechanical power source;

an AC electric generator drivingly connected to the mechanical power source;

a power converter configured to convert alternating current produced by the AC electric generator into direct current;

one or more power loads connected to the power converter; and

power-supply controls configured to execute a control method including;

receiving inputs related to conditions of operation of the machine; and

controlling a speed at which the mechanical power source drives the AC electric generator as a function of an estimated power need of one or more of the power loads.

26. The machine of claim 25, wherein the power loads connected to the power converter include at least one of an air conditioner compressor and an electric heating element.

27. The machine of claim 26, wherein controlling the speed at which the mechanical power source drives the AC electric generator includes adjusting controls to increase the speed at which the mechanical power source drives the AC electric generator in response to an increase in the estimated power need of one or more of the power loads.

28. The machine of claim 25, wherein controlling the speed at which the mechanical power source drives the AC electric generator dependent upon the estimated power need of one or more of the power loads includes:

causing the mechanical power source to drive the AC electric generator at a first speed under a first set of conditions, including the estimated power need of a set of one or more power loads being below a first amount of power; and

causing the mechanical power source to drive the AC electric generator at a second speed, higher than the first, under a second set of conditions, including the estimated power need of the set of one or more of the power loads being above the first amount of power.

29. The machine of claim 25, wherein controlling the speed at which the mechanical power source drives the AC electric generator dependent upon the estimated power need of one or more of the power loads includes increasing the speed at which the mechanical power source drives the AC electric generator in response to an increase in the estimated power need of one or more of the power loads.

30. The machine of claim 25, wherein:

controlling the speed at which the mechanical power source drives the AC electric generator includes controlling the operating speed of the mechanical power source.

31. The machine of claim 25, wherein the mechanical power source and the electric generator are components of an auxiliary power unit.

32. The machine of claim 25, wherein the mechanical power source is a prime mover.