Electronic control of solenoid operated circuit breakers

• US 4,918,566 A
• Filed: 05/27/1988
• Issued: 04/17/1990
• Est. Priority Date: 05/27/1988
• Status: Expired due to Term

• Current Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Original Assignee: Westinghouse Electric Company LLC (Brookfield Asset Management Incorporated)
• Inventors: Davidson, David L., Brodsky, Bruce L.
• Primary Examiner(s): Paschall, M. H.
• Assistant Examiner(s): Gaffin, Jeffrey A.
• Application Number:
  US07/199,417
• Time in Patent Office: 690 Days
• Field of Search: 361/153, 361/160, 361/166, 361/168.1, 361/169.1, 361/170, 361/171, 361/172, 361/191, 361/194, 307/11, 307/12, 307/31, 307/34, 307/35, 307/38, 307/39, 307/40
• US Class Current: 361/166
• CPC Class Codes: H01H 2300/03 Application domotique, e.g. for house automation, bus connected switches, sensors, loads or intelligent wiring
• CPC Class Codes: H01H 71/46 having means for operating auxiliary contacts additional to the main contacts
• CPC Class Codes: H01H 89/06 Combination of a manual reset circuit with a contactor, i.e. the same circuit controlled by both a protective and a remote control device
• CPC Class Codes: H01H 9/167 Circuits for remote indication
• CPC Class Codes: H01H 9/56 for ensuring operation of the switch at a predetermined point in the ac cycle
• CPC Class Codes: Y02B 90/20 Smart grids as enabling technology in buildings sector smart grids supporting the management or operation of end-user stationary applications in general, or like technologies with no associated climate change mitigation effect Y04S20/00
• CPC Class Codes: Y04S 20/14 Protecting elements, switches, relays or circuit breakers

Abstract

An electronic controller, connected to a digital communication network, is responsive to commands from a master controller to control solenoid operated circuit breakers. The electronic controller also determines the status of all circuit breakers and reports back to the master controller to verify that the command from the master controller was executed and to provide historical data regarding the status of the circuit breakers. The electronic controller is synchronized to the same alternating current (AC) power source as the circuit breakers to control the operation of the respective circuit breakers to minimize electromagnetic interference (EMI) caused by the switching of the circuit breakers. The electronic controller further controls the operation of the circuit breakers to reduce the duty cycle of the power supply for the circuit breaker solenoids.

Claims

1. An electronic controller for controlling solenoid operated circuit breakers, used to provide electrical power to one or more electrical loads, coupled to a master controller through a common network line forming a bidirectional communication link therebetween, comprising:

receiving means for receiving commands from said master controller over said common network line;

control means for controlling said circuit breaker in accordance with the command from said master controller; and

circuit breaker status determining means for determining the status of the circuit breaker independently of the electrical load to which the circuit breaker is connected to verify that the command was properly executed.

2. An electronic controller as recited in claim 1 further including means for transmitting the circuit breaker status back to the master controller.

3. An electronic controller as recited in claim 1 further including means for transmitting any unexpected changes in the circuit breaker status to the master controller.

4. An electronic controller as recited in claim 1 further including comparison means for determining if the current circuit breaker status is the same as the command status prior to executing the command.

5. An electronic controller as recited in claim 4 further including means responsive to said comparison means for actuating the circuit breaker only if the command status is different from said current status.

6. An electronic controller as recited in claim 1 wherein said circuit breaker status determining means includes means for monitoring an auxiliary contact on said circuit breaker.

7. An electronic controller as recited in claim 1 wherein said control means includes means for controlling a plurality of solenoid operated circuit breakers.

8. An electronic controller as recited in claim 7 wherein said plurality is an even number.

9. An electronic controller as recited in claim 8 wherein said control means includes means for controlling the circuit breakers such that only one circuit breaker is actuated at a time.

10. An electronic controller as recited in claim 9 wherein said control means includes means for actuating one-half of the total number of circuit breakers coupled to said electronic controller during positive half cycles of the source of alternating current electrical power and actuating the other one-half during negative half cycles of said source of alternating current electrical power.

11. An electronic controller as recited in claim 10 wherein said control means includes means for actuating two circuit breakers during one cycle during successive positive and negative half cycles.

12. An electronic controller as recited in claim 11 further including means for inhibiting the control means on alternate cycles.

13. An electronic controller for controlling solenoid operated circuit breakers coupled to a master controller through a common network line forming a bidirectional communication link therebetween, comprising:

receiving means for receiving commands from said master controller over said common network line;

control means for controlling said circuit breaker in accordance with the command from said master controller;

circuit breaker status determining means for determining the status of the circuit breaker to verify that the command was properly executed; and

means for synchronizing said current circuit breaker status determining means with a reference signal.

14. An electronic controller as recited in claim 13 wherein said reference signal is a source of alternating current electrical power.

15. An electronic controller as recited in claim 14 wherein said current circuit breaker status determining means includes means for determining the status of the circuit breakers at or near the peaks of the source of alternating current electrical power.

16. An electronic controller as recited in claim 13 further including means for inhibiting said control means from actuating the circuit breakers at or near peaks of the source of alternating current electrical power.

17. An electronic controller as recited in claim 13 wherein said control means is adapted to control circuit breakers connected to a single phase source of electrical power.

18. An electronic controller as recited in claim 13 wherein said control means includes means for controlling the switching of the circuit breakers such that the circuit breakers are switched at or near the zero crossings of the course of alternating current electrical power.

19. An electronic controller as recited in claim 13 wherein said control means is adapted to control circuit breakers connected to a three-phase source of electrical power.

20. An electronic controller as recited in claim 13 wherein said control means includes means for controlling the switching of the circuit breakers such that the circuit breakers are switched at or near 60°

of any positive or negative half cycle of the source of alternating current electrical power.

21. An electronic controller for controlling solenoid operated circuit breakers, used to supply alternating current electrical power to one or more electrical loads, having a status contact comprising:

means for determining the circuit breaker status by determining whether the status contact is pen or closed independently of the electrical load to which the circuit breaker is connected;

comparing means responsive to said determining means for comparing the current circuit breaker status with the desired circuit breaker status; and

control means responsive to said comparing means for changing said circuit breaker status when the current circuit breaker status is different from the desired circuit breaker status.

22. An electronic controller as recited in claim 21 further including inhibiting means for inhibiting said control means if said current circuit breaker status is the same as the desired circuit breaker status.

23. An electronic controller as recited in claim 21 wherein said control means is synchronized to a reference signal.

24. An electronic controller as recited in claim 23 wherein said reference signal is a source of alternating current electrical power.

25. An electronic controller as recited in claim 21 wherein said control means includes means for only actuating one circuit breaker at a time.

26. An electronic controller as recited in claim 24 wherein said control means includes means for actuating only one breaker during any half cycle.

27. An electronic controller as recited in claim 26 further including means for inhibiting aid control means during predetermined cycles of said source of alternating current electrical power.

28. An electronic controller for controlling solenoid operated circuit breakers having a status contact coupled to a source of alternating current electrical power comprising:

means for determining the circuit breaker status by determining whether the status contact is open or closed;

comparing means responsive to said determining means for comparing the current circuit breaker status with the desired circuit breaker status;

control means responsive to said comparing means for changing said circuit breaker status when the current circuit breaker status is different from the desired circuit breaker status; and

means for reducing the electromagnetic interference (EMI) caused by the switching of the circuit breakers.

29. An electronic controller as recited in claim 28 wherein said EMI reducing means includes means for inhibiting switching of a circuit breaker at or near a peak of said source alternating current electrical power.

30. An electronic controller as recited in claim 29 wherein said control means includes means for controlling switching of circuit breakers connected to a three-phase source of electrical power such that the switching occurs at or near 60°

of any positive or negative half cycle of the source of alternating current electrical power.

31. An electronic controller as recited in claim 29 wherein said control means includes means for controlling switching of the circuit breakers connected to a single phase source of electrical power such that the switching occurs at or near zero crossings.

32. An electronic controller responsive to commands to controlling solenoid operated circuit breakers coupled to a source of alternating current electrical power comprising:

first means responsive to said commands for actuating at least one of said circuit breakers as commanded; and

second means for controlling the number of said circuit breakers actuated by said first means during a predetermined time period; and

means for synchronizing said first means to said source of alternating current electrical power.

33. An electronic controller as recited in claim 32 wherein said predetermined time period is one half cycle of said source of alternating current electrical power.

34. An electronic controller as recited in claim 32 wherein said second means includes third means for allowing only two circuit breakers to be actuated per cycle of said source of alternating current electrical power.

35. An electronic controller as recited in claim 32 wherein said third means for actuating one circuit breaker on a positive half cycle and one circuit breaker on a negative half cycle.

36. An electronic controller as recited in claim 32 further including means for controlling the point along the positive and negative half cycles to reduce electromagnetic interference (EMI) caused by switching.

37. An electronic controller as recited in claim 36 further including inhibiting means for inhibiting actuation of circuit breakers at or near the peaks of the positive and negative half cycles.