Fail-resistant solid state interruption system

• US 5,170,310 A
• Filed: 11/29/1990
• Issued: 12/08/1992
• Est. Priority Date: 11/29/1990
• Status: Expired due to Term

• Current Assignee: Square D Company (Schneider Electric SE)
• Original Assignee: Square D Company (Schneider Electric SE)
• Inventors: Liptak, Julius M., Fixemer, James V., Studtmann, George H., Ward, Donald H.
• Primary Examiner(s): Pellinen, A. D.
• Assistant Examiner(s): JACKSON, STEPHEN W
• Application Number:
  US07/619,776
• Time in Patent Office: 740 Days
• Field of Search: 361/94, 361/100, 361/65, 361/78, 361/79, 361/13, 361/7, 361/5, 361/18, 361/88, 307/38, 307/39
• US Class Current: 361/94
• CPC Class Codes: H01H 9/548 Electromechanical and static switch connected in series
• CPC Class Codes: H02H 1/04 Arrangements for preventing response to transient abnormal conditions, e.g. to lightning or to short duration over voltage or oscillations; Damping the influence of dc component by short circuits in ac networks
• CPC Class Codes: H02H 3/083 for three-phase systems
• CPC Class Codes: H02H 7/30 Staggered disconnection

Abstract

A solid state circuit interruption arrangement in a distributed power network provides fast and reliable circuit interruption. A common power source provides power to a plurality of loads via respective current paths. A main circuit breaker and a plurality of solid state circuit breakers are arranged to interrupt the current paths in response to command signals sent from a central controller. Current sensors and voltage sensors are coupled to the current paths for monitoring purposes. An automatic controller responds to any of the current sensors detecting a fault condition by automatically generating a command signal, which forces the associated solid state breaker to interrupt the associated current path. Thereafter, the controller automatically generates a signal to the main circuit breaker to interrupt the power provided from the common power source in the event that the associated current path is not interrupted by the solid state breaker. Alternatively, or in addition, the main interruption device may interrupt the current path when its own internal sensing mechanism detects a magnitude of current that is beyond a predetermined level. Also, the controller automatically generates a signal to the main breaker to interrupt the power provided from the common power source in the event that any of the branch breakers fails in the "off" or interrupted, condition. Other features include a finned housing structure which provides cooling means for the breaker system without the need for cooling fans.

Claims

1. A static switch interruption arrangement, comprising:

a main interruption device and a static switch interruption device, connected in series in a current path between a source and a load, for interrupting and establishing current flow therebetween;

a sensor, coupled to the current path of the static switch interruption device; and

automatic control means, responsive to the sensor, for automatically controlling the main interruption device and the static switch interruption device, wherein the automatic control means is capable of generating a first signal to cause the static switch interruption device to interrupt the current path, and is capable of automatically generating a second signal to cause the main interruption device to interrupt the current path in response to the static switch interruption device failing;

wherein the sensor includes a voltage sensor which senses voltage input to the static switch interruption device and wherein the automatic control means controls the static switch interruption device in response to the voltage sensor.

2. A static switch interruption arrangement according to claim 1, wherein the sensor senses the status of the static switch interruption device when it is establishing its associated current path and when it is interrupting its associated current path.

3. A static switch interruption arrangement, according to claim 1, further including time delay means, coupled with said automatic control means, for delaying current path interruption in response to a transient condition in the associated current path.

4. A static switch interruption arrangement, according to claim 1, wherein the automatic control means controls the static switch interruption device for establishing as well as for interrupting, the current path.

5. A static switch interruption arrangement comprising:

a main interruption device and a static switch interruption device, connected in series in a current path between a source and a load, for interrupting and establishing current flow therebetween;

a sensor, coupled to the current path of the static switch interruption device;

automatic control means, responsive to the sensor, for automatically controlling the main interruption device and the static switch interruption device, wherein the automatic control means is capable of generating a first signal to cause the static switch interruption device to interrupt the current path, and is capable of automatically generating a second signal to cause the main interruption device to interrupt the current path in response to the static switch interruption device failing, wherein the sensor includes a voltage sensor which senses voltage input to the static switch interruption device and wherein the automatic control means control the static switch interruption device in response to the voltage sensor; and

pair of bleeder-resistor circuits, respectively coupled to either side of the static switch interruption device and each having a terminal coupled to a ground terminal, which is used to establish an artificial neutral terminal.

6. A static switch interruption arrangement, according to claim 5, further including time delay means, coupled with said automatic control means, for delaying current path interruption in response to a transient condition in the associated current path.

7. A static switch interruption arrangement, according to claim 5, wherein the sensor includes a voltage sensor which senses voltage input to the static switch interruption device and wherein the automatic control means controls the static switch interruption device in response to the voltage sensor.

8. A static switch interruption arrangement, comprising:

a main interruption device and a static switch interruption device, connected in series in a current path between a source and a load, for interrupting and establishing current flow therebetween;

a sensor, coupled to the current path of the static switch interruption device; and

automatic control means, responsive to the sensor, for automatically controlling the main interruption device and the static switch interruption device, wherein the automatic control means is capable of generating a first signal to cause the static switch interruption device to interrupt the current path, and is capable of automatically generating a second signal to cause the main interruption device to interrupt the current path in response to the static switch interruption device failing, wherein the sensor includes a voltage sensor which senses voltage input to the static switch interruption device and wherein the automatic control means controls the static switch interruption device in response to the voltage sensor, wherein the control means includes a micro-computer which is preprogrammed for comparing current, sensed by the sensor, with a threshold and for said automatic generation of the first and second signals, and further including a delay circuit arranged so that the control means does not cause interruption of any current path in response to a transient condition in the associated current path.

9. A static switch interruption arrangement, according to claim 8, wherein the sensor indicates when the static switch interruption device fails to interrupt the associated current path.

10. A static switch interruption arrangement, according to claim 8, wherein the sensor is coupled across the static switch interruption device.

11. A static switch interruption arrangement, according to claim 10, wherein the sensor includes a voltage sensor which senses voltage input to the static switch interruption device and wherein the automatic control means controls the static switch interruption device in response to the voltage sensor.

12. A solid state interruption arrangement for interrupting a current path between a load and a source, said arrangement comprising:

main interruption means, responsive to a main interruption signal and having an input and output port, the input port being connected to receive the power from the source;

solid state interruption means, responsive to a solid state interruption signal and having an input port connected to the output port of the main interruption means and having an output port connected to the load;

first sensing means, coupled to the current path between the load and the solid state interruption means, for sensing a first power related parameter in the current path;

second sensing means, coupled to the current path, for sensing a second power related parameter in the current path; and

an automatic controller, responsive to the first and second sensing means, for determining if at least one of said first and second power related parameters exceeds a predetermined threshold and automatically generating the solid state interruption signal when the threshold is exceeded and, thereafter, automatically generating the main interruption signal in the event that the current path is not interrupted by the solid state interruption means;

wherein each of the main and solid state interruption signals causes the associated interruption means to block the current path with the main interruption means acting to back-up the solid state interruption means and wherein one of the first and second power related parameters is voltage and the other of the first and second power related parameters is current.

13. A solid state circuit interruption arrangement, according to claim 12, wherein the first sensing means includes a voltage sensor having an output which is coupled to the automatic controller.

14. A solid state circuit interruption arrangement, according to claim 13, wherein the automatic controller automatically generates the main interruption signal to the main interruption means in response to said voltage sensor indicating that a voltage is sensed.

15. A solid state circuit interruption arrangement, according to claim 13, wherein the second sensing means includes a current sensor having an output coupled to the automatic controller.

16. A solid state circuit interruption arrangement, according to claim 15, wherein the automatic controller automatically generates the main interruption signal to the main interruption means in response to at least one of two conditions (a) said voltage sensor indicating that the sensed voltage exceeds a reference voltage and (b) the associated current sensor indicating that a current above a reference level is sensed.

17. A solid state circuit interruption arrangement, according to claim 12, further including a control station, communicatively coupled to the automatic controller, for remotely monitoring the current path.

18. A solid state circuit interruption arrangement, according to claim 17, wherein the control station further includes means for remotely controlling the main and solid state interruption signals.

19. A solid state circuit interruption arrangement, according to claim 12, wherein one of the first and second power related parameters is voltage and the other of the first and second power related parameters is current.

20. A solid state circuit interruption arrangement, according to claim 12, further including a bleeder resistor circuit comprising at least one resistor coupled to the output port of the solid state interruption means to draw a portion of current if the solid state interruption means fails in such a manner that the current path remains uninterrupted.

21. A solid state circuit interruption arrangement, for interrupting a current path between a load and a source, said arrangement comprising:

main interruption means, responsive to a main interruption signal and having an input and output port, the input port being connected to receive the power from the source;

solid state interruption means, responsive to a solid state interruption signal and having an input port connected to the output port of the main interruption means and having an output port connected to the load;

first sensing means, coupled to the current path between the load and the solid state interruption means, for sensing a first power related parameter in the current path;

second sensing means, coupled to the current path, for sensing a second power related parameter in the current path; and

an automatic controller, responsive to the first and second sensing means, for determining if at least one of said first and second power related parameters exceeds a predetermined threshold and automatically generating the solid state interruption signal when the threshold is exceeded and, thereafter, automatically generating the main interruption signal in the event that the current path is not interrupted by the solid state interruption means;

wherein each of the main and solid state interruption signals causes the associated interruption means to block the current path with the main interruption means acting to back-up the solid state interruption means; and

voltage sensing means, coupled to the input port of the solid state interruption means, for generating a signal which indicates if the solid state interruption means fails in such a manner that the current path remains uninterrupted.

22. A solid state circuit interruption arrangement, comprising:

main interruption means, responsive to a main interruption signal and having an input and output port, the input port being connected to receive the power from the source;

solid state interruption means, responsive to a solid state interruption signal and having an input port connected to the output port of the main interruption means and having an output port connected to the load;

first sensing means, coupled to the current path between the load and the solid state interruption means, for sensing a first power related parameter in the current path;

second sensing means, coupled to the current path, for sensing a second power related parameter in the current path; and

an automatic controller, responsive to the first and second sensing means, for determining if at least one of said first and second power related parameters exceeds a predetermined threshold and automatically generating the solid state interruption signal when the threshold is exceeded and, thereafter, automatically generating the main interruption signal in the event that the current path is not interrupted by the solid state interruption means;

wherein each of the main and solid state interruption signals causes the associated interruption means to block the current path with the main interruption means acting to back-up the solid state interruption means, wherein one of the first and second power related parameters is voltage and the other of the first and second power related parameters is current; and

means for drawing power from the current path for providing power to the solid state circuit interruption arrangement.

23. A solid state circuit interruption arrangement, according to claim 22, further including time delay means, coupled with said automatic controller, for delaying current path interruption in response to a transient condition in the associated current path.

24. A solid state interruption arrangement for interrupting a current path between a load and a source, said arrangement comprising:

main interruption means, responsive to a main interruption signal and having an input and output port, the input port being connected to receive the power from the source;

solid state interruption means, responsive to a solid state interruption signal and having an input port connected to the output port of the main interruption means and having an output port connected to the load;

first sensing means, coupled to the current path between the output port of the solid state interruption means and the load, for sensing a first power related parameter in the current path;

second sensing means, coupled to the current path between the main interruption means and the solid state interruption means, for sensing a second power related parameter in the current path;

a pair of bleeder-resistor circuits, respectively coupled to either side of the solid state interruption means and each having a terminal coupled to a ground terminal, which is used to establish an artificial neutral terminal;

determination means for sensing the magnitude of the current through at least one of the bleeder-resistor circuits; and

an automatic controller, responsive to the determination means and the first and second sensing means, which determines if at least one of said first and second power related parameters exceeds a predetermined threshold and automatically generates the solid state interruption signal when the threshold is exceeded and, thereafter, automatically generates the main interruption signal in the event that the current path is not interrupted by the solid state interruption means;

wherein each of the main and solid state interruption signals causes the associated interruption means to block the current path with the main interruption means acting to back-up the solid state interruption means.

25. A solid state circuit interruption arrangement, according to claim 24, further including time delay means, coupled with said automatic controller, for delaying current path interruption in response to a transient condition in the associated current path.

26. A solid state circuit interruption arrangement, according to claim 24, wherein the determination means generates a signal which is used to detect overload currents and wherein the determination means includes amplification means for amplifying the sensed magnitude of the current through said at least one of the bleeder-resistor circuits.

27. A solid state circuit interruption arrangement, according to claim 24, wherein the determination means includes means, responsive to the solid state interruption means failing with the current path being interrupted, for detecting currents through said at least one of the bleeder-resistor circuits.

28. A solid state circuit interruption arrangement in a distributed power network wherein a common power source provides power to a plurality of loads so as to establish a plurality of current paths emanating from the source, the arrangement comprising:

main interruption means, having an input and output port, the input port being connected to receive the power from the source;

a plurality of solid state interruption means, each having an input port connected to the output port of the main interruption means and an output port connected to one of the loads;

a plurality of voltage sensors each of which is coupled to the current path between the output port of an associated one of the solid state interruption means and the associated one of the loads;

a plurality of current sensors each of which is coupled to the current path of the solid state interruption means; and

an automatic controller responsive to each of the voltage and current sensors for detecting a fault condition in one of the current paths and automatically generating a signal to the associated solid state interruption means so that the associated current path is interrupted when the condition is detected and thereafter automatically generating a signal to the main interruption means to interrupt the power provided from the common power source in the event that the associated current path is not interrupted by the solid state interruption means.

29. A solid state circuit interruption arrangement, according to claim 28, wherein the automatic controller automatically generates the signal to the main interruption means in response to one of said voltage sensors indicating that a voltage, above a reference level, is sensed after automatically generating a signal to the associated solid state interruption means.

30. A solid state circuit interruption arrangement, according to claim 28, wherein the automatic controller automatically generates the signal to the main interruption means in response to one of said voltage sensors indicating that a voltage, above a reference level, is sensed or the associated current sensor indicating that a current, above a reference level, is sensed after automatically generating a signal to the associated solid state interruption means.

31. A solid state circuit interruption arrangement, according to claim 30, further including a housing structure having a finned heat sink for dissipating heat generated by the plurality of solid state interruption means.

32. A solid state circuit interruption arrangement, according to claim 28, further including a housing structure having a finned heat sink for dissipating heat generated by the plurality of solid state interruption means and wherein the finned heat sink includes a planar member for mounting each of said plurality of solid state interruption means.

33. A solid state circuit interruption arrangement, according to claim 28, further including means for drawing power from the current path for providing power to the solid state circuit interruption arrangement and including power-on delay means, responsive to the power being provided to the solid state circuit interruption arrangement and coupled with the automatic controller, for forcing the respective current paths of the plurality of solid state interruption means to remain interrupted for a predetermined period of time.

34. A solid state circuit interruption arrangement, according to claim 28, further including means for drawing power from the current path for providing power to the solid state circuit interruption arrangement and including power-on delay means, responsive to the power being provided to the solid state circuit interruption arrangement and coupled with the automatic controller, for preventing transients generated by making the current paths via the main interruption means.

35. A solid state circuit interruption arrangement, according to claim 28, further including a transient suppression network coupled so as to protect the main interruption means at its input port.

36. A solid state circuit interruption arrangement, according to claim 35, further including a transient suppression network coupled between the main interruption means and said plurality of solid state interruption means.