Systems and methods for freewheel contactor circuits

Patent metadata

Field	Value
Publication number	US-9786457-B2
Application number	US-201514596674-A
Country	US
Kind code	B2
Filing date	Jan 14, 2015
Priority date	Jan 14, 2015
Publication date	Oct 10, 2017
Grant date	Oct 10, 2017

Abstract

A circuit for use with a contactor including at least one contact is provided. The circuit includes a first segment including a voltage source, a first coil, a second coil, and a first transistor, wherein the first segment is configured to selectively conduct a closing current through the first coil, the second coil, and the first transistor to close the at least one contact. The circuit further includes a second segment including the first coil, a second transistor, and a first diode, wherein the second segment is configured to selectively conduct a holding current through the first coil, the second transistor, and the first diode to hold the at least one contact closed, and wherein the first diode is arranged such that substantially all current produced by the voltage source flows through the first coil.

First claim

What is claimed is:

1. A circuit for use with a contactor including at least one contact, said circuit comprising:
a first segment comprising:
a voltage source;
a first coil;
a second coil; and
a first transistor, wherein said first segment is configured to selectively conduct a closing current through said first coil, said second coil, and said first transistor to close the at least one contact; and

a second segment comprising:
said first coil;
a second transistor; and
a first diode, wherein said second segment is configured to selectively conduct a holding current through said first coil, said second transistor, and said first diode to hold the at least one contact closed, and wherein said first diode is arranged such that all current produced by said voltage source flows through said first coil.

2. A circuit in accordance with claim 1 , further comprising a third segment that comprises:
said second coil;
a second diode; and
a first Zener diode, said third segment configured to conduct a current through said second coil, said second diode, and said first Zener diode in sequence.

3. A circuit in accordance with claim 2 , further comprising a third transistor electrically coupled between said second diode and said second transistor.

4. A circuit in accordance with claim 3 , wherein said third transistor comprises a PNP bipolar junction transistor.

5. A circuit in accordance with claim 1 , wherein said voltage source, said first coil, said second coil, and said first transistor form a current loop.

6. A circuit in accordance with claim 1 , wherein said first coil, said second transistor, and said first diode form a current loop.

7. A circuit in accordance with claim 1 , wherein said second coil is configured to:
store energy when the closing current passes through said second coil; and
discharge the stored energy to initiate a flow of the holding current in said second segment.

8. A system comprising:
a contactor comprising at least one contact; and
a circuit comprising:
a first segment comprising:
a voltage source;
a first coil;
a second coil; and
a first transistor, wherein said first segment is configured to selectively conduct a closing current through said first coil, said second coil, and said first transistor to close said at least one contact; and

a second segment comprising:
said first coil;
a second transistor; and
a first diode, wherein said second segment is configured to selectively conduct a holding current through said first coil, said second transistor, and said first diode to hold said at least one contact closed, and wherein said first diode is arranged such that all current produced by said voltage source flows through said first coil.

9. A system in accordance with claim 8 , wherein said circuit further comprises a third segment comprising:
said second coil;
a second diode; and
a first Zener diode, said third segment configured to conduct a current through said second coil, said second diode, and said first Zener diode in sequence.

10. A system in accordance with claim 9 , further comprising a third transistor electrically coupled between said second diode and said second transistor.

11. A system in accordance with claim 10 , wherein said third transistor comprises a PNP bipolar junction transistor.

12. A system in accordance with claim 8 , wherein said voltage source, said first coil, said second coil, and said first transistor form a current loop.

13. A system in accordance with claim 8 , wherein said first coil, said second transistor, and said first diode form a current loop.

14. A system in accordance with claim 8 , wherein said second coil, is configured to:
store energy when the closing current passes through said second coil; and
discharge the stored energy to initiate a flow of the holding current in said second segment.

15. A method of assembling a circuit for use with a contactor including at least one contact, said method comprising:
electrically coupling a voltage source, a first coil, a second coil, and a first transistor together to form a first segment, the first segment configured to selectively conduct a closing current through the first coil, the second coil, and the first transistor to close the at least one contact; and
electrically coupling the first coil, a second transistor, and a first diode together to form a second segment, the second segment configured to selectively conduct a holding current through the first coil, the second transistor, and the first diode to hold the at least one contact closed, wherein the first diode is arranged such that all current produced by the voltage source flows through the first coil.

16. A method in accordance with claim 15 , further comprising electrically coupling the second coil, a second diode, and a first Zener diode together to form a third segment, die third segment configured to conduct a current through the second coil, the second diode, and the first Zener diode in sequence.

17. A method in accordance with claim 16 , further comprising electrically coupling a third transistor between the second diode and the second transistor.

18. A method in accordance with claim 17 , wherein coupling a third transistor comprises coupling a PNP bipolar junction transistor.

19. A method in accordance with claim 15 , wherein electrically coupling a voltage source, a first coil, a second coil, and a first transistor together comprises electrically coupling the voltage source, the first coil, the second coil, and the first transistor together such that the first segment forms a current loop.

20. A method in accordance with claim 15 , wherein electrically coupling the first coil, a second transistor, and a first diode together comprises electrically coupling the first coil, the second transistor, and the first diode together such that the second segment forms a current loop.

21. A method of operating a contactor circuit that includes a first segment having a voltage source, a first coil, a second coil, and a first transistor, and a second segment having the first coil, a second transistor, and a first diode, the method comprising:
conducting a closing current through the first segment to close a contact associated with the contactor circuit, wherein the first diode is arranged such that all current produced by the voltage source flows through the first coil; and
conducting a holding current through the second segment to hold the contact closed.

22. A method in accordance with claim 21 , wherein conducting a holding current comprises conducting a holding current of approximately 3 amps.

23. A method in accordance with claim 22 , wherein conducting a holding current comprising conducting a holding current such that approximately 0.1 Watts are dissipated in the second transistor.

24. A method in accordance with claim 21 , wherein conducting a holding current comprises turning on the second transistor with an activation current on the order of microamps.

25. A method in accordance with claim 21 , further comprising opening the contact by turning off the first transistor and dissipating energy in the second segment.

Assignees

• Gen Electric

Inventors

• Ramsey Stephan Robert

Classifications

• H01H47/06

  by changing number of serially-connected turns or windings · CPC title

• H01H47/04 Primary

  for holding armature in attracted position, e.g. when initial energising circuit is interrupted; for maintaining armature in attracted position, e.g. with reduced energising current {(with switching regulator H01H47/325)} · CPC title

• H01H47/32 Primary

  Energising current supplied by semiconductor device · CPC title