Power controller

• US 9,702,910 B2
• Filed: 08/14/2014
• Issued: 07/11/2017
• Est. Priority Date: 08/26/2013
• Status: Active Grant

• Current Assignee: Micropac Industries, Inc.
• Original Assignee: Micropac Industries, Inc.
• Inventors: Baldridge, Wayne
• Primary Examiner(s): Ali, Mohammad
• Assistant Examiner(s): AZAD, MD ABUL K
• Application Number:
  US14/460,308
• Publication Number:
  US 20150057822A1
• Time in Patent Office: 1,062 Days
• Field of Search: None
• CPC Class Codes: G01R 21/06 by measuring current and voltage G01R21/08 - G01R21/133 take precedence
• CPC Class Codes: H02H 3/08 responsive to excess current responsive to abnormal temperature caused by excess current H02H5/04
• CPC Class Codes: H03K 17/0822 in field-effect transistor switches
• CPC Class Codes: H03K 17/18 Modifications for indicating state of switch
• CPC Class Codes: H03K 17/61 using transformer coupling
• CPC Class Codes: H03K 17/691 using transformer coupling
• CPC Class Codes: H03K 17/785 controlling field-effect transistor switches
• CPC Class Codes: H03K 17/7955 using phototransistors
• CPC Class Codes: H03K 2217/0027 Measuring means of, e.g. currents through or voltages across the switch
• CPC Class Codes: H03K 2217/0081 Power supply means, e.g. to the switch driver

Abstract

A power controller includes an input power terminal, an output power terminal, a power switching circuit connected between the input power terminal and the output power terminal, a detection circuit connected to the power switching circuit, one or more data interfaces, and a control device connected to the detection circuit and the one or more data interfaces. The detection circuit measures a load current and a current squared time (I²t) value between the input power terminal and the output power terminal. The control device automatically turns the power switching circuit “OFF” whenever the load current exceeds a first value or the current squared time value exceeds a second value or an “OFF” signal is received from the one or more data interfaces, and automatically turns the power switching circuit “ON” whenever an “ON” signal is received from the one or more data interfaces.

Claims

1. A power controller comprising:

an input power terminal;

an output power terminal;

a power switching circuit comprising a first power field-effect transistor having a drain connected to the input power terminal and a gate connected to a control device, and a second power field-effect transistor having a gate connected to the control device and a source connected to the output power terminal;

a detection circuit connected to the power switching circuit that measures a load current and a current squared time (I²t) value between the input power terminal and the output power terminal, wherein the detection circuit comprises;

one or more resistors connected in series between a source of the first power field-effect transistor and a drain of the second power field effect transistor, such that a first voltage across the one or more resistors is proportional to the load current, and

a RC circuit connected in parallel with the one or more resistors such that a second voltage across the RC circuit is proportional to the current squared time value;

one or more data interfaces; and

the control device connected to the power switching circuit, the detection circuit and the one or more data interfaces that automatically turns the power switching circuit “

OFF”

whenever the load current exceeds a first value or the current squared time value exceeds a second value or an “

OFF”

signal is received from the one or more data interfaces, and automatically turns the power switching circuit “

ON”

whenever an “

ON”

signal is received from the one or more data interfaces.

2. The power controller as recited in claim 1, wherein the first value and the second value are set in accordance with a “

Must Not Trip”

curve and a “

Must Trip”

curve, wherein the “

Must Not Trip”

curve and the “

Must Trip”

curve are separated by a “

May Trip”

region.

3. The power controller as recited in claim 1, wherein the detection circuit further comprises a voltage detection circuit that measures a load voltage.

4. The power controller as recited in claim 1, wherein the load voltage is at least 500 V.

5. The power controller as recited in claim 1, wherein the power controller comprises an AC power controller having a rated operating voltage of 0 to greater than or equal to 280 VAC, or a DC power controller having a rated operating voltage of 0 to greater than or equal to 400 VDC.

6. The power controller as recited in claim 1, wherein the control device comprises a fault latch circuit and a timer circuit.

7. The power controller as recited in claim 1, wherein the control device comprises one or more processors or a control circuit.

8. The power controller as recited in claim 7, wherein the one or more processors are programmable.

9. The power controller as recited in claim 7, wherein the one or more processors include one or more device drivers to interface with one or more plug-and-play internal or external devices.

10. The power controller as recited in claim 1, wherein the detection circuit further comprises a thermal sensor.

11. The power controller as recited in claim 1, wherein the detection circuit further comprises thermal shutdown circuit.

12. The power controller as recited in claim 1, wherein the detection circuit further comprises a smoke sensor.

13. The power controller as recited in claim 1, wherein the detection circuit further comprises a ground fault detector.

14. The power controller as recited in claim 1, wherein the detection circuit further comprises a load voltage detector.

15. The power controller as recited in claim 1, further comprising a power line signaling circuit communicably coupled to the control device.

16. The power controller as recited in claim 1, further comprising a lock down control circuit connected to the control device.

17. The power controller as recited in claim 1, wherein the one or more data interfaces are communicably coupled to the control device and electrically isolated from the control device, detection circuit and the switching circuit.

18. The power controller as recited in claim 1, wherein the one or more data interfaces comprise an analog communications interface or a digital communications interface.

19. The power controller as recited in claim 1, wherein the one or more data interfaces comprise an optical coupling device.

20. The power controller as recited in claim 1, wherein the one or more data interfaces comprise a display, a keyboard, one or more buttons, or one or more selector switches.

21. The power controller as recited in claim 1, wherein the one or more data interfaces comprise a control interface and a status interface.

22. The power controller as recited in claim 1, wherein the one or more data interfaces provide a remote control and monitoring of the power controller, a status of the power controller, a measurement of a current passing between the input power terminal and the output power terminal to a remote device, or a measurement of one or more thermal conditions to a remote device.

23. The power controller as recited in claim 1, wherein the power controller is an AC power controller and does not require the use of an output clamping circuit.

24. The power controller as recited in claim 1, further comprising a power source disposed within the power controller and connected to at least the control device and the detection circuit.

25. The power controller as recited in claim 24, wherein the power source comprises one or more batteries or one or more external control power source terminals.

26. The power controller as recited in claim 1, further comprising:

an isolated control power supply disposed within the power controller and connected to at least the control device and the detection circuit; and

one or more external control power source terminals connected to the isolated control power supply.

27. The power controller as recited in claim 26, further comprising a filter circuit connected between the one or more external control power source terminals and the isolated control power supply.

28. The power controller as recited in claim 1, further comprising an enclosure in which the one or more data interfaces, the input power terminal and the output power terminal are accessible from an exterior of the enclosure, and the control device, the detection circuit and the power switching circuit are disposed within the enclosure.

29. The power controller as recited in claim 28, wherein the enclosure is encapsulated.

30. The power controller as recited in claim 1, further comprising:

an antenna; and

a wireless transceiver connected to the antenna and the control device.

31. A power controller comprising:

an enclosure;

an input power terminal accessible from an exterior of the enclosure;

an output power terminal accessible from an exterior of the enclosure;

a power switching circuit disposed within the enclosure and connected in series between the input power terminal and the output power terminal, the power switching circuit comprising one or more power field-effect transistors;

a detection circuit disposed within the enclosure and connected to the power switching circuit, the detection circuit comprising a load current detection circuit having one or more resistors connected in series between one of the one or more power field-effect transistors and one of the power terminals, or between two of the one or more power field-effect transistors, such that a first voltage across the one or more resistors is proportional to the load current, a current squared time (I²t) detection circuit having a RC circuit connected in parallel with the one or more resistors such that a second voltage across the RC circuit is proportional to a current squared time (I²t) value, and a load voltage detection circuit that measures a load voltage between the input power terminal and the output power terminal;

one or more data interfaces accessible from an exterior of the enclosure;

an isolation circuit disposed within the enclosure and connected to the one or more data interfaces;

a control device disposed within the enclosure and connected to the power switching circuit, the detection circuit and the isolation circuit that automatically turns the power switching circuit “

OFF”

whenever the load current exceeds a first value or the current squared time value exceeds a second value or an “

OFF”

signal is received from the one or more isolated data interfaces, and automatically turns the power switching circuit “

ON”

whenever an “

ON”

signal is received from the one or more isolated data interfaces;

an isolated control power supply disposed within the enclosure and connected to at least the control device and the detection circuit;

one or more external control power source terminals accessible from an exterior of the enclosure; and

a filter circuit disposed within the enclosure and connected between the one or more external control power source terminals and the isolated control power supply.

32. The power controller as recited in claim 31, wherein the first value and the second value are set in accordance with a “

Must Not Trip”

curve and a “

Must Trip”

curve, wherein the “

Must Not Trip”

curve and the “

Must Trip”

curve are separated by a “

May Trip”

region.

33. The power controller as recited in claim 31, wherein the load voltage is at least 500 V.

34. The power controller as recited in claim 31, wherein the power controller comprises an AC power controller having a rated operating voltage of 0 to greater than or equal to 280 VAC, or a DC power controller having a rated operating voltage of 0 to greater than or equal to 400 VDC.

35. The power controller as recited in claim 31, wherein the control device comprises a fault latch circuit and a timer circuit.

36. The power controller as recited in claim 31, wherein the control device comprises one or more processors or a control circuit.

37. The power controller as recited in claim 36, wherein the one or more processors are programmable.

38. The power controller as recited in claim 36, wherein the one or more processors include one or more device drivers to interface with one or more plug-and-play internal or external devices.

39. The power controller as recited in claim 31, wherein the detection circuit further comprises a thermal sensor, a thermal shutdown circuit, a smoke sensor, or a ground fault detector.

40. The power controller as recited in claim 31, wherein the detection circuit further comprises a load voltage detector.

41. The power controller as recited in claim 31, further comprising a power line signaling circuit communicably coupled to the control device.

42. The power controller as recited in claim 31, further comprising a lock down control circuit connected to the control device.

43. The power controller as recited in claim 31, wherein the one or more isolated data interfaces comprise an analog communications interface or a digital communications interface.

44. The power controller as recited in claim 31, wherein the one or more isolated data interfaces comprise an optical coupling device.

45. The power controller as recited in claim 31, wherein the one or more isolated data interfaces comprise a display, a keyboard, one or more buttons, or one or more selector switches.

46. The power controller as recited in claim 31, wherein the one or more isolated data interfaces comprise a control interface and a status interface.

47. The power controller as recited in claim 31, wherein the one or more isolated data interfaces provide a remote control and monitoring of the power controller, a status of the power controller, a measurement of a current passing between the input power terminal and the output power terminal to a remote device, or a measurement of one or more thermal conditions to a remote device.

48. The power controller as recited in claim 31, wherein the power controller does not require the use of an output clamping circuit.

49. The power controller as recited in claim 31, wherein the enclosure is encapsulated.

50. The power controller as recited in claim 31, further comprising:

an antenna; and

a wireless transceiver connected to the antenna and the control device.

51. A method for controlling a power from a power supply to a load comprising the steps of:

providing a power controller comprising an input power terminal, an output power terminal, a power switching circuit comprising a first power field effect transistor having a drain connected to the input power terminal and a gate connected to a control device, and a second power field-effect transistor having a gate connected to the control device and a source connected to the output power terminal, a detection circuit connected to the power switching circuit, one or more data interfaces, the control device connected to the power switching circuit, the detection circuit and the one or more data interfaces, and wherein the power controller is series connected between the power supply and the load using the input power terminal and the output power terminal, and wherein the detection circuit comprises;

one or more resistors connected in series between a source of the first power field-effect transistor and a drain of the second power field effect transistor, such that a first voltage across the one or more resistors is proportional to the load current, and

a RC circuit connected in parallel with the one or more resistors such that a second voltage across the RC circuit is proportional to the current squared time value;

measuring a load current and a current squared time (I²t) value between the input power terminal and the output power terminal using the detection circuit;

automatically turning the power switching circuit “

OFF”

using the control device whenever the load current exceeds a first value or the current squared time value exceeds a second value or an “

OFF”

signal is received from the one or more data interfaces; and

automatically turning the power switching circuit “

ON”

using the control device whenever an “

ON”

signal is received from the one or more data interfaces.

52. The method as recited in claim 51, wherein the first value and the second value are set in accordance with a “

Must Not Trip”

curve and a “

Must Trip”

curve, wherein the “

Must Not Trip”

curve and the “

Must Trip”

curve are separated by a “

May Trip”

region.

53. The method as recited in claim 51, wherein the detection circuit further comprises a voltage detection circuit and further comprising the steps of:

measuring a load voltage using the voltage detection circuit; and

automatically turning the power switching circuit “

OFF”

using the control device.

54. The method as recited in claim 51, wherein the load voltage is at least 500 V.

55. The method as recited in claim 51, wherein the power controller comprises an AC power controller having a rated operating voltage of 0 to greater than or equal to 280 VAC, or a DC power controller having a rated operating voltage of 0 to greater than or equal to 400 VDC.

56. The method as recited in claim 51, wherein the control device comprises a fault latch circuit and a timer circuit.

57. The method as recited in claim 51, wherein the control device comprises one or more processors or a control circuit.

58. The method as recited in claim 57, wherein the one or more processors are programmable.

59. The method as recited in claim 57, wherein the one or more processors include one or more device drivers to interface with one or more plug-and-play internal or external devices.

60. The method as recited in claim 51, wherein the detection circuit further comprises a thermal sensor, a thermal shutdown circuit, a smoke sensor, or a ground fault detector.

61. The method as recited in claim 51, wherein the detection circuit further comprises a load voltage detector.

62. The method as recited in claim 51, further comprising a power line signaling circuit communicably coupled to the control device.

63. The method as recited in claim 51, further comprising a lock down control circuit connected to the control device.

64. The method as recited in claim 51, wherein the one or more data interfaces are communicably coupled to the control device and electrically isolated from the control device, detection circuit and the switching circuit.

65. The method as recited in claim 51, wherein the one or more data interfaces comprise an analog communications interface or a digital communications interface.

66. The method as recited in claim 51, wherein the one or more data interfaces comprise an optical coupling device.

67. The method as recited in claim 51, wherein the one or more data interfaces comprise a display, a keyboard, one or more buttons, or one or more selector switches.

68. The method as recited in claim 51, wherein the one or more data interfaces comprise a control interface and a status interface.

69. The method as recited in claim 51, further comprising the steps of:

providing a remote control and monitoring of the power controller using the one or more data interfaces;

providing a status of the power controller using the one or more data interfaces;

providing a measurement of a current passing between the input power terminal and the output power terminal to a remote device using the one or more data interfaces;

or

providing a measurement of one or more thermal conditions to a remote device using the one or more data interfaces.

70. The method as recited in claim 51, wherein the power controller does not require the use of an output clamping circuit.

71. The method as recited in claim 51, further comprising a power source disposed within the power controller and connected to at least the control device and the detection circuit.

72. The method as recited in claim 71, wherein the power source comprises one or more batteries or one or more external control power source terminals.

73. The method as recited in claim 51, further comprising:

an isolated control power supply disposed within the power controller and connected to at least the control device and the detection circuit; and

one or more external control power source terminals connected to the isolated control power supply.

74. The method as recited in claim 73, further comprising a filter circuit connected between the one or more external control power source terminals and the isolated control power supply.

75. The method as recited in claim 51, further comprising an enclosure in which the one or more data interfaces, the input power terminal and the output power terminal are accessible from an exterior of the enclosure, and the control device, the detection circuit and the power switching circuit are disposed within the enclosure.

76. The method as recited in claim 75, wherein the enclosure is encapsulated.

77. The method as recited in claim 51, further comprising:

an antenna; and

a wireless transceiver connected to the antenna and the control device.