System and Method for Load Control

• US 20110031950A1
• Filed: 09/01/2010
• Published: 02/10/2011
• Est. Priority Date: 10/18/2007
• Status: Active Grant

• Current Assignee: Hammerhead International Incorporated
• Original Assignee: Hammerhead International Incorporated
• Inventors: Sopuch, John A., Hodges, Joseph W.
• Granted Patent: US 8,004,123 B2
• Time in Patent Office: Days
• US Class Current: 323/284
• 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 system is described including a means for receiving a potential and selectively supplying the potential to a load. The receiving and supplying means being responsive to a load control signal to supply the potential to the load when the load control signal is present. The system also includes a means for measuring a load demand. Also included is a means for controlling the receiving and supplying means. The controlling means continuously providing the load control signal when the load demand is greater than a predetermined threshold. The controlling means temporarily providing the load control signal to determine the load demand when the load demand is less than the predetermined threshold.

Claims

1-20. -20. (canceled)

21. An electric load controller comprising:

a load switch receiving an electric potential from a power source and selectively supplying the received electric potential to a load in response to a received load control signal;

a load measurer measuring a load demand of the load; and

a controller powered by the power source and in communication with the load switch and the load measurer, the controller continuously delivering the load control signal to the load switch when the measured load demand is greater than a first threshold load demand, the controller delivering the load control signal to the load switch for a threshold time period when the measured load demand is less than a second threshold load demand;

wherein the controller delivers the load control signal to the load switch for a learning time period and ascertains minimum and maximum load demands measured by the load measurer during the learning time period, the controller determining the first and second threshold load demands based at least in part on at least one of the minimum and maximum load demands.

22. The electric load controller of claim 21, wherein the first threshold load demand equals the second threshold load demand.

23. The electric load controller of claim 21, wherein the first and second threshold load demands are near a midpoint between the minimum and maximum load demands.

24. The electric load controller of claim 21, wherein the load demand comprises at least one of a current and power used by the load.

25. The electric load controller of claim 21, wherein the controller stores in memory the minimum and maximum load demands measured by the load measurer during the learning time period.

26. The electric load controller of claim 21, wherein the controller causes the load measurer to continuously measure the load demand of the load when the measured load demand is greater than the first threshold load demand.

27. The electric load controller of claim 21, wherein the controller periodically delivers the load control signal to the load switch for the threshold time period when the measured load demand is less than the second threshold load demand to allow the load measurer to measure the load demand of the load.

28. The electric load controller of claim 21, wherein the load has an active state when the measured load demand is greater than the first threshold load demand and an inactive state when the measured load demand is less than the second threshold load demand, the controller ceasing delivery of the load control signal to the load switch during the inactive state of the load and after cessation of delivery of the load control signal, the controller periodically delivering the load control signal to the load switch for the threshold time period to allow the load measurer to measure the load demand of the load and determine the state of the load.

29. The electric load controller of claim 21, wherein the load measurer measures a voltage drop for a resistor in series with the electric potential and the load to determine the load demand.

30. The electric load controller of claim 21, wherein the load switch comprises at least one of a field effect transistor, an electronic switch, and a bidirectional electronic switch.

31. The electric load controller of claim 21, further comprising first and second electrical connectors in electrical communication with the load switch for selectively supplying the electric potential to the load.

32. A method of controlling an electrical load, the method comprising:

receiving an electric potential from a power source;

selectively supplying the received electric potential to a load in response to a received load control signal;

measuring a load demand of the load;

continuously delivering the load control signal to cause supplying the received electric potential to the load when the measured load demand is greater than a first threshold load demand;

delivering the load control signal for a threshold time period to cause supplying the received electric potential to the load for the threshold time period when the measured load demand is less than a second threshold load demand;

delivering the load control signal for a learning time period to cause supplying the received electric potential to the load for the learning time period;

measuring minimum and maximum load demands of the load during the learning time period; and

determining the first and second threshold load demands based at least in part on at least one of the minimum and maximum load demands.

33. The method of claim 32, wherein the first threshold load demand equals the second threshold load demand.

34. The method of claim 32, further comprising determining the first and second threshold load demands near a midpoint between the minimum and maximum load demands.

35. The method of claim 32, wherein the load demand comprises at least one of a current and power used by the load.

36. The method of claim 32, further comprising storing in memory the minimum and maximum load demands measured during the learning time period.

37. The method of claim 32, further comprising continuously measuring the load demand of the load when the measured load demand is greater than the first threshold load demand.

38. The method of claim 32, further comprising periodically delivering the load control signal the threshold time period when the measured load demand is less than the second threshold load demand to allow measurement of the load demand of the load.

39. The method of claim 32, wherein the load has an active state when the measured load demand is greater than the first threshold load demand and an inactive state when the measured load demand is less than the second threshold load demand, the method further comprising:

ceasing delivery of the load control signal during the inactive state of the load and after cessation of delivery of the load control signal, periodically delivering the load control signal for the threshold time period to allow measurement of the load demand of the load; and

determining the state of the load.

40. The method of claim 32, further comprising measuring a voltage drop for a resistor in series with the electric potential and the load to determine the load demand.