Determining power

• US 20080103609A1
• Filed: 10/12/2006
• Published: 05/01/2008
• Est. Priority Date: 10/12/2006
• Status: Active Grant

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Inventors: Smith, David E.
• Granted Patent: US 7,793,117 B2
• Time in Patent Office: Days
• US Class Current: 700/22
• CPC Class Codes: B41J 2/04548 Details of power line section of control circuit
• CPC Class Codes: B41J 2/04586 controlling heads of a type not covered by groups B41J2/04575 - B41J2/04585, or of an undefined type

Abstract

Embodiments of determining power are disclosed.

Claims

1. A method comprising:

determining an amount of power to supply to a load included in a first system, using a relationship between a voltage provided by a power source to the first system and a current supplied by the power source to the first system, to reduce a magnitude of a change in the voltage resulting from operation of one or more other systems coupled to the power source.

2. The method as recited in claim 1, further comprising:

determining the relationship between the voltage and the current.

3. The method as recited in claim 2, wherein:

the determining the relationship includes measuring a plurality of voltages provided by the power source to the first system and measuring a plurality of currents provided by the power source to the first system corresponding to the plurality of the voltages.

4. The method as recited in claim 3, wherein:

the determining the relationship includes controlling the first system to dissipate a plurality of different amounts of the power in the load corresponding to the plurality of the voltages and the plurality of the currents.

5. The method as recited in claim 1, further comprising:

monitoring the voltage provided to the first system by the power source; and

detecting the change in the voltage provided by the power source resulting from the operation of the one or more of the other systems coupled to the power source.

6. The method as recited in claim 1, wherein:

the using the relationship includes determining from the relationship an expected reduction in the magnitude of the change in the voltage to result from supplying the amount of the power to the load.

7. The method as recited in claim 1, wherein:

the determining the relationship includes determining an estimate of a magnitude of an impedance associated with the power source.

8. The method as recited in claim 1, wherein:

the determining the relationship includes determining a set of corresponding pairs of expected changes in the magnitude of the voltage resulting from changes in the current.

9. The method as recited in claim 2, wherein:

the determining the relationship includes determining a time interval during which the changes to the current provided by the power source to the one or more other systems coupled to the power source substantially equal zero.

10. The method as recited in claim 1, wherein:

the load includes a heater;

the first system includes a printing system; and

the power source includes an AC mains.

11. The method as recited in claim 1, wherein:

the determining the amount of the first power includes determining from the using the relationship the amount of the power sufficient to reduce the magnitude of the change in the voltage to a value at least as great as a lower operating voltage of a second load coupled to the power source.

12. The method as recited in claim 1, wherein:

the determining the amount of the power includes accessing a look-up table specifying the relationship using a desired amount of the reduction in the magnitude of the change in the voltage that results from the power source supplying the current corresponding to the amount of the power.

13. The method as recited in claim 12, further comprising:

causing the desired amount of the power to be supplied to the load, wherein the desired amount of the reduction in the magnitude of the change in the voltage corresponds to a value of the voltage that exceeds a threshold voltage for proper operation of a second load coupled to the power source.

14. An apparatus, comprising:

a processing device configured to determine an amount of a power to be supplied to a load of a system to reduce a change in a value of a voltage provided by a power source that results from the operation of to one or more other systems.

15. The apparatus as recited in claim 14, further comprising:

a power controller configured to adjust the power supplied to the load according to the amount of the power determined.

16. The apparatus as recited in claim 14, wherein:

the processing device includes a configuration to determine the amount of the power so that the reduction in the change in the value of the voltage results in the value of the voltage provided by the power source exceeding a lower operating threshold voltage of a second load included in the system by at least a predetermined value.

17. The apparatus as recited in claim 14, further comprising:

a device configured to measure the value of the voltage and a value of a current provided to the system by the power source; and

wherein the processing device includes a configuration to determine a relationship between the change in the value of the voltage and a change in the value of the current provided to the system by the power source during a time interval in which the changes to current provided by the power source to the one or more other systems coupled to the power source substantially equal zero.

18. The apparatus as recited in claim 17, wherein:

the time interval corresponds to one or more of;

during power up of the system, periodically during operation of the system or, a predetermined time period during a day.

19. A system, comprising:

a device to determine an estimate of a voltage supplied by a power source to the system and an estimate of a current supplied by the power source to the system;

a heater;

a power converter to supply power to the heater; and

circuitry to determine an amount of the power to be supplied to the heater to reduce a change in the voltage resulting from current drawn by another system.

20. The system as recited in claim 19, further comprising:

an image forming mechanism to form an image on media;

a DC power supply, wherein the circuitry includes a capability to determine the amount of the power, using a relationship between a change in the voltage supplied by the power source resulting from a change in the current supplied by the power source to the system, so that the voltage remains above an operating voltage threshold of the DC power supply during operation of the system.