Aircraft applicable circuit imbalance detection and circuit interrupter and packaging thereof

• US 20050018369A1
• Filed: 06/03/2004
• Published: 01/27/2005
• Est. Priority Date: 02/01/2001
• Status: Active Grant

• Current Assignee: Hydro-Aire Aerospace Corporation (Crane Company)
• Original Assignee: Hydro-Aire, Inc. (Crane Company)
• Inventors: Rusali, Rudy, Bax, Ronald A., King, Timothy
• Granted Patent: US 7,362,551 B2
• Time in Patent Office: Days
• US Class Current: 361/42
• CPC Class Codes: H01H 3/001 Means for preventing or breaking contact-welding
• CPC Class Codes: H01H 83/04 with testing means for indicating the ability of the switch or relay to function properly
• CPC Class Codes: H01H 83/14 operated by imbalance of two or more currents or voltages, e.g. for differential protection
• CPC Class Codes: H01H 83/144 with differential transformer
• CPC Class Codes: H02H 1/06 Arrangements for supplying operative power power supply arrangements in general G05F, H02M
• CPC Class Codes: H02H 3/04 with warning or supervision in addition to disconnection, e.g. for indicating that protective apparatus has functioned watching of pilot wires H02H1/0084; protection of protective arrangements H02H7/008; indication of the state of electronic switches H03K17/18
• CPC Class Codes: H02H 3/05 with means for increasing reliability, e.g. redundancy arrangements for logic circuits H03K19/003
• CPC Class Codes: H02H 3/105 responsive to excess current and fault current to earth
• CPC Class Codes: H02H 3/32 involving comparison of the voltage or current values at corresponding points in different conductors of a single system, e.g. of currents in go and return conductors
• CPC Class Codes: H02H 3/33 using summation current transformers H02H3/347 takes precedence
• CPC Class Codes: H02H 3/347 using summation current transformers
• CPC Class Codes: H02H 7/09 against over-voltage; against reduction of voltage; against phase interruption

Abstract

The aircraft applicable current imbalance detection and circuit interrupter interrupts an electrical circuit when a current imbalance is sensed. The current imbalance detection and circuit interrupter includes a housing, power supplies, a sensor system for sensing a current imbalance at the line side of the electrical circuit, a logic controller and a power controller including a power relay having contacts capable of surviving carry-break and make-carry-break types of ground fault conditions at anticipated current levels. At power up, the device performs a test to confirm that none of the relay contacts have failed in a closed position, and to check whether a switching FET which controls the relay coil has shorted.

Claims

1. An aircraft applicable current imbalance detection and circuit interrupter for monitoring the current within an electrical circuit and interrupting the electrical circuit, the electrical circuit having a line side and a load side with an electrical load connected thereto, the aircraft applicable current imbalance detection and circuit interrupter comprising:

a housing including electrical connector means for connecting to the electrical circuit line side and load side;

a power supply disposed in the housing and electrically connected to the electrical circuit;

a sensor system disposed in the housing for sensing a current imbalance in the electrical circuit and for providing a sensor signal indicating the existence of an undesirable current within the electrical circuit based on said sensing of said current imbalance;

a logic controller disposed in the housing and configured to be powered by the electrical circuit being monitored, to receive the sensor signal from the sensor system and to output a fault signal representing a fault; and

a power controller disposed in the housing configured to receive said fault signal from the logic controller and to remove power to the load side of the electrical circuit responsive to the fault signal from the logic controller, the power controller including a power relay having contacts capable of surviving carry-break and make-carry-break types of ground fault conditions at anticipated current levels.

2. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein said contacts are rated for a 25 Amp current to make-carry-break fault current levels of about 500 Amps with no appreciable change in contact resistance.

3. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein said contacts are rated for a 50 Amp current to make-carry-break fault current levels of about 1500 Amps with no appreciable change in contact resistance.

5. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein the aircraft applicable current imbalance detection and circuit interrupter interrupts arcing within a device being operated by the electrical circuit.

6. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein the housing has an envelope compatible with that of existing power controllers for the aircraft and using the same monitoring configurations.

7. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein the electrical connector means comprises an electrical connector plate on the housing connected to the line side and load side of the electrical circuit being monitored.

8. The aircraft applicable current imbalance detection and circuit interrupter of claim 7, wherein said electrical connector plate comprises a plurality of electrical connectors.

9. The aircraft applicable current imbalance detection and circuit interrupter of claim 8, wherein said electrical connector plate comprises a first pair of connectors accommodating a first load line, a second pair of connectors accommodating a second load line, and a third pair of connectors accommodating a third load line.

10. The aircraft applicable current imbalance detection and circuit interrupter of claim 1, wherein the aircraft applicable current imbalance detection and circuit interrupter is configured to test during a power up sequence to determine if the aircraft applicable current imbalance detection and circuit interrupter is operating properly.

11. An aircraft applicable current imbalance detection and circuit interrupter for interrupting an electrical circuit to an electrical load, the electrical circuit having a line side and a load side, the aircraft applicable current imbalance detection and circuit interrupter comprising:

a housing having electrical connector means for connecting to the electrical circuit line side and load side;

a power supply disposed in the housing and connected to the electrical circuit;

a sensor system disposed in the housing for sensing a current imbalance in the electrical circuit and for providing a sensor signal indicating the existence of a current imbalance within the electrical circuit based on said sensing of said current imbalance;

a direct current (DC) controlled power controller configured to remove power to the load side of the electrical circuit when de-energized, the power controller including a power relay having contacts capable of surviving carry-break and make-carry-break types of ground fault conditions at anticipated current levels;

a logic controller disposed in the housing and configured to be powered by the power supply, to receive an external relay control signal and the sensor signal from the sensor system, to compare the sensor signal with a predetermined range for acceptable operation for the electrical circuit, to output a fault signal representing a current imbalance and de-energized the power controller when the sensor signal exceeds said predetermined range;

a fault indicator configured to receive said fault signal from the logic controller, to indicate a current imbalance condition has occurred; and

a reset switch to reset the fault indicator and the current imbalance detection and circuit interrupter;

wherein the housing has a form factor that packages the current imbalance detection and circuit interrupter circuitry in a space compatible with an existing power controller used in the aircraft.

12. The aircraft applicable current imbalance detection and circuit interrupter of claim 11 wherein:

the logic controller receives the external relay control signal and processes this signal to energize and de-energize the power controller; and

the external relay control signal, depending on the aircraft, may be alternate current (AC) or direct current (DC).

13. The aircraft applicable current imbalance detection and circuit interrupter of claim 12 wherein the logic controller is capable of accepting and processing either an AC or DC external relay control signal.

14. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein said contacts are rated for a 25 Amp current to make-carry-break fault current levels of about 500 Amps with no appreciable change in contact resistance.

15. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein the aircraft applicable current imbalance detection and circuit interrupter receives power to operate exclusively from the line side of the electrical circuit being monitored.

16. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein said contacts are rated for a 50 Amp current to make-carry-break fault current levels of about 1500 Amps with no appreciable change in contact resistance.

17. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein the aircraft applicable current imbalance detection and circuit interrupter suppresses arcing within a device being operated by the electrical circuit.

18. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein the aircraft applicable current imbalance detection and circuit interrupter discontinues ground fault conditions within a device being operated by the electrical circuit.

19. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein said aircraft applicable current imbalance detection and circuit interrupter is sized and configured to replace an existing aircraft power controller.

20. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein the electrical connection means comprises an electrical connector for connecting to the line side, the load side and the external relay control signal.

21. The aircraft applicable current imbalance detection and circuit interrupter of claim 20, wherein said electrical connector comprises a plurality of electrical connectors.

22. The aircraft applicable current imbalance detection and circuit interrupter of claim 21, wherein said electrical connector comprises a first pair of connectors accommodating a first line and load side, a second pair of connectors accommodating a second line and load side, and a third pair of connectors accommodating a third line and load side, and a pair of connectors accommodating the external relay control signal.

23. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein said housing includes at least one circuit board mounted within the housing for mounting components of the aircraft applicable current imbalance detection and circuit interrupter.

24. The aircraft applicable current imbalance detection and circuit interrupter of claim 11, wherein the aircraft applicable current imbalance detection and circuit interrupter is configured to test during a power up sequence to determine if the aircraft applicable current imbalance detection and circuit interrupter is operating properly.

25. An aircraft applicable current imbalance detection and circuit interrupter for interrupting an electrical circuit to an electrical load, the electrical circuit having a line side and a load side, said interrupter comprising:

a housing having electrical connector means for connecting to the electrical circuit line side and load side;

at least one power supply disposed in the housing and connected to the electrical circuit;

a sensor system disposed in the housing for sensing a current imbalance in the electrical circuit and for providing a sensor signal indicating the existence of a current imbalance within the electrical circuit based on said sensing of said current imbalance;

a logic controller disposed in the housing and configured to be powered by one of the power supplies, to receive an external relay control signal and the sensor signal from the sensor system, and to compare the sensor signal with a predetermined range for acceptable operation for the electrical circuit and to interrupt the relay control signal when the sensor signal exceeds said predetermined range;

a power controller configured to be energized by the relay control signal and to remove power to the load side of the electrical circuit when the relay control signal is interrupted, the power controller including a power relay having contacts capable of surviving carry-break and make-carry-break types of ground fault conditions at anticipated current levels;

a fault indicator configured to receive said fault signal from the logic controller, to illuminate indicating a current imbalance condition has occurred; and

a reset switch to reset the fault indicator and the current imbalance detection and circuit interrupter.

26. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein said contacts are rated for a 25 Amp current to make-carry-break fault current levels of about 500 Amps with no appreciable change in contact resistance.

27. The aircraft applicable current imbalance detection and circuit interrupter of claim 25 wherein said sensor system comprises a current transformer connected to the load side of the circuit.

28. The aircraft applicable current imbalance detection and circuit interrupter of claim 25 wherein:

the logic controller receives the relay control signal to directly power the power controller;

the relay control signal, depending on the aircraft, may be alternate current (AC) or direct current (DC); and

the type of power controller corresponds to the AC or DC relay control signal.

29. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein said contacts are rated for a 50 Amp current to make-carry-break fault current levels of about 1500 Amps with no appreciable change in contact resistance.

30. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein the aircraft applicable current imbalance detection and circuit interrupter receives power to operate exclusively from the line side of the electrical circuit being monitored.

31. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein the aircraft applicable current imbalance detection and circuit interrupter discontinues arcing within a device being operated by the electrical circuit.

32. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein the aircraft applicable current imbalance detection and circuit interrupter discontinues ground fault conditions within a device being operated by the electrical circuit.

33. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein the electrical connection means comprises an electrical connector for connecting to the line side, the load side and the relay control signal.

34. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein said electrical connector comprises a plurality of electrical connectors.

35. The aircraft applicable current imbalance detection and circuit interrupter of claim 25, wherein the aircraft applicable current imbalance detection and circuit interrupter is configured to test during a power up sequence to determine if the aircraft applicable current imbalance detection and circuit interrupter is operating properly.