SYSTEM AND METHOD FOR LOAD CONTROL

• US 20120074792A1
• Filed: 09/20/2011
• Published: 03/29/2012
• Est. Priority Date: 10/18/2007
• Status: Active Grant

• Current Assignee: John A. Sopuch, Joseph W. Hodges, Richard J. Hodges, Thomas D. Lasky
• Original Assignee: John A. Sopuch, Joseph W. Hodges, Richard J. Hodges, Thomas D. Lasky
• Inventors: Hodges, Joseph W., Sopuch, John A., Lasky, Thomas D., Hodges, Richard J.
• Granted Patent: US 8,779,633 B2
• Time in Patent Office: Days
• US Class Current: 307/126
• CPC Class Codes: H02H 3/12 responsive to underload or no-load for motors H02H7/0827
• CPC Class Codes: H02J 9/005 using a power saving mode for copiers G03G15/5004
• CPC Class Codes: Y02B 70/30 Systems integrating technologies related to power network operation and communication or information technologies for improving the carbon footprint of the management of residential or tertiary loads, i.e. smart grids as climate change mitigation technology in the buildings sector, including also the last stages of power distribution and the control, monitoring or operating management systems at local level
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

A device includes a load sensor configured to measure a load demand that indicates that a load is operating in an active state or an inactive state. A load switch is configure to selectively supply electric energy to the a load in accordance with a load control signal. A controller in communication with the load switch and the load sensor is configured to compare the load demand to a load threshold, generate the load control signal based at least in part on the load demand relative to the load threshold, and transmit the load control signal to the load switch when the load demand is substantially equal to or greater than the load threshold. The controller is further configured to determine the load threshold based at least in part on the load demand when the load is operating in either the active state or the inactive state.

Claims

1-20. -20. (canceled)

21. A device comprising:

a load sensor configured to measure a load demand, wherein the load demand indicates that a load is operating in at least one of an active state and an inactive state;

a load switch configure to selectively supply electric energy to the a load in accordance with a load control signal; and

a controller in communication with the load switch and the load sensor, wherein the controller is configured to compare the load demand to a load threshold, generate the load control signal based at least in part on the load demand relative to the load threshold, and transmit the load control signal to the load switch when the load demand is substantially equal to or greater than the load threshold, and

wherein the controller is configured to determine the load threshold based at least in part on the load demand when the load is operating in at least one of the active state and the inactive state.

22. A device as set forth in claim 21, wherein the controller is configured to determine the load threshold by monitoring the load demand over a predetermined amount of time.

23. A device as set forth in claim 21, wherein the controller is configured to set the load threshold to a value above the load demand when the load is operating in the inactive state.

24. A device as set forth in claim 21, wherein the controller is configured to set the load threshold to a value below the load demand when the load is operating in the active state.

25. A device as set forth in claim 21, wherein the controller is configured to store the determined load threshold in a memory device.

26. A device as set forth in claim 21, wherein the controller is configured to apply a hysteresis range to the determined load threshold.

27. A device as set forth in claim 21, wherein the controller is configured to automatically determine the load threshold based on whether the load is in at least one of the active state and the inactive state.

28. A device as set forth in claim 21, wherein the controller is configured to sample the load demand at a plurality of time steps to determine the load threshold.

29. A device as set forth in claim 28, wherein the controller is configured to calculate an average of the load demands sampled to determine the load threshold.

30. A device as set forth in claim 21, wherein the controller is configured to determine a minimum power-on time for the load and wherein the controller is configured to compare the load demand to the load threshold after the minimum power-on time has elapsed.

31. A power-saving device comprising:

a load sensor configured to measure a load demand; and

a controller in communication with the load sensor and configured to compare the load demand to a load threshold and enable the load if the load demand is substantially equal to or greater than the load threshold,

wherein the controller is configured to determine the load threshold during a time when a load is operating in an inactive state.

32. A power-saving device as set forth in claim 31, wherein the controller is configured to determine the load threshold by monitoring the load demand over a predetermined amount of time.

33. A power-saving device as set forth in claim 31, wherein the controller is configured to set the load threshold to a value above the load demand when the load is operating in the inactive state.

34. A power-saving device as set forth in claim 31, wherein the controller is configured to set the load threshold to a value below the load demand when the load is operating in the active state.

35. A power-saving device as set forth in claim 31, wherein the controller is configured to apply a hysteresis range to the determined load threshold.

36. A power-saving device as set forth in claim 31, wherein the controller is configured to automatically determine the load threshold.

37. A power-saving device as set forth in claim 31, wherein the controller is configured to sample the load demand at a plurality of time steps and calculate an average of the load demands sampled to determine the load threshold.

38. A power-saving device as set forth in claim 31, wherein the controller is configured to determine a minimum power-on time for the load and wherein the controller is configured to compare the load demand to the load threshold after the minimum power-on time has elapsed.

39. A method comprising:

determining a load threshold when a load is operating in at least one of an active state and an inactive state;

comparing the load threshold to a load demand;

enabling the load if the load demand is substantially equal to or greater than the load threshold; and

disabling the load if the load demand is less than the load threshold.

40. A method as set forth in claim 39, wherein determining the load threshold includes monitoring the load demand over a predetermined amount of time

41. A method as set forth in claim 39, wherein determining the load threshold includes:

sampling the load demand at a plurality of time steps; and

calculating an average of the load demands sampled.

42. A method as set forth in claim 39, wherein comparing the load threshold to the load demand includes comparing the load threshold to the load demand after a minimum power-on time for the load has elapsed.