Smart wire harness for an electrical circuit

• US 20040150410A1
• Filed: 01/31/2003
• Published: 08/05/2004
• Est. Priority Date: 01/31/2003
• Status: Active Grant

• Current Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Gopalakrishan, Suresh, Schoepf, Thomas J., Naidu, Malakondaiah
• Granted Patent: US 6,833,713 B2
• Time in Patent Office: Days
• US Class Current: 324/536
• CPC Class Codes: H02H 1/0015 Using arc detectors
• CPC Class Codes: H02H 3/30 using pilot wires or other signalling channel

Abstract

A direct current electrical circuit having a smart wire harness that has integrated electronics which measure both voltage and current through wires of the harness to detect and protect the electrical current from parallel and serial arc faults occurring within a protection zone. The protection zone is disposed directly between two smart connectors of the wire harness which are in communication with one another via a series of signal wires of the harness to detect serial or parallel arc faults within the protection zone. To measure serial arc faults, a voltage drop of the positive wire is measured at each smart connector and a difference taken which equals the serial arc voltage. If this voltage differential increases to a preset value, a switching device which provides power to the smart wire harness is opened. To detect parallel arc faults, that is those arcs which jump between the positive wire and the ground wire of the wire harness, a current is measured at both ends of the positive wire of the wire harness via the same smart connectors. If the ending current is less than the beginning current, signaling a parallel arc fault due to the arc resistance of the arc itself, the same switching device is opened.

Claims

1. A smart wire harness for detecting serial and parallel arc faults, the wire harness comprising:

a positive conductor having a first voltage and a second voltage;

a first smart connector for measuring the first voltage;

a second smart connector for measuring the second voltage, wherein positive conductor is engaged electrically between the first and second smart connectors so that the first and second connectors are wired in series for detecting a serial arc fault across the positive conductor;

a first signal wire for transferring the value of the second voltage from the second smart connector to the first smart connector; and

a switching device for providing electrical power to the positive conductor, wherein the switching device is constructed and arranged to open when a predetermined voltage differential limit is exceeded indicating a serial arc fault.

2. The smart wire harness set forth in claim 1 comprising:

a first current of the positive conductor measured at the first smart connector via a first current detector;

a second current of the positive conductor measured at the second smart connector via a second current detector;

a second signal wire for transferring the value of the second current from the second smart connector to the first smart connector; and

wherein the switching device opens when the second current is less than the first current indicating a parallel arc fault across the positive conductor.

3. The smart wire harness set forth in claim 2 comprising:

a negative conductor wired in parallel to the positive conductor and engaged electrically between the first and second smart connectors, the negative conductor having a first reference voltage measured at the first smart connector and a second reference voltage measured at the second smart connector;

a third signal wire for transferring the value of the second reference voltage from the second smart connector to the first smart connector; and

wherein the switching device opens when the difference between the quantity of the second voltage minus the second reference voltage and the quantity of the first voltage minus the first reference voltage exceeds the voltage differential limit.

4. The smart wire harness set forth in claim 3 comprising a comparator housed within the first smart connector, wherein the comparator receives and processes the first voltage, the first current, the first reference voltage, the second voltage, the second current, and the second reference voltage.

5. The smart wire harness set forth in claim 2 wherein the first and second current detectors are Hall sensors.

6. The smart wire harness set forth in claim 2 wherein the first and second current detectors are shunt sensors.

7. The smart wire harness set forth in claim 1 comprising:

a first current of the positive conductor measured at the first smart connector;

a second current of the positive conductor measured at the second smart connector;

a negative conductor wired in parallel to the positive conductor and engaged electrically between the first and second smart connectors;

a multiplexer utilized with the second smart connector for transferring the value of the second current and the second voltage across the first signal wire;

a de-multiplexer utilized with the first smart connector for separating the values of the second voltage and the second current received from the first signal wire; and

wherein the switching device opens when the second current is less than the first current indicating a parallel arc fault across the positive conductor.

8. The smart wire harness set forth in claim 7 comprising:

the negative conductor having a first reference voltage measured at the first smart connector and a second reference voltage measured at the second smart connector;

a third signal wire for transferring the value of the second reference voltage from the second smart connector to the first smart connector; and

wherein the switching device opens when the difference between the quantity of the second voltage minus the second reference voltage and the quantity of the first voltage minus the first reference voltage exceeds the voltage differential limit.

9. The smart wire harness set forth in claim 8 comprising a comparator housed within the first smart connector, wherein the comparator receives and processes the first voltage, the first current, the first reference voltage, the second voltage, the second current, and the second reference voltage

10. A direct current electrical circuit comprising:

a protection zone;

a smart wire harness for detecting serial and parallel arc faults, the smart wire harness having;

a positive conductor extending through the protection zone, the positive conductor having a first voltage and a second voltage, a first smart unit for measuring the first voltage,

a second smart unit for measuring the second voltage, wherein the protection zone is disposed between the first and second smart connectors and wherein the positive conductor is engaged electrically between the first and second smart units so that the first and second smart units are wired in series for detecting a serial arc fault across the positive conductor, and

a first signal wire for transferring the value of the second voltage from the second smart connector to the first smart connector;

a switching device for providing electrical power to the positive conductor, wherein the switching device is constructed and arranged to open when a predetermined voltage differential limit is exceeded indicating a serial arc fault;

a direct current power source engaged electrically between the switching device and a chassis ground, wherein the switching device is disposed between the power source and the first smart unit; and

a load engaged electrically between the positive conductor and the chassis ground, wherein the second smart unit is disposed between the protection zone and the load.

11. The direct current electrical circuit set forth in claim 10 comprising:

a first current of the positive conductor measured at the first smart unit via a first current detector;

a second current of the positive conductor measured at the second smart unit via a second current detector;

a second signal wire for transferring the value of the second current from the second smart unit to the first smart unit; and

wherein the switching device opens when the second current is less than the first current indicating a parallel arc fault across the positive conductor.

12. The direct current electrical circuit set forth in claim 11 comprising:

a plurality of positive conductors, wherein the positive conductor is one of the plurality of positive conductors; and

the first and second current detectors being coiled-type of current sensors wherein the first current detector is coiled about the plurality of positive conductors at the first smart unit and wherein the second current detector is coiled about the plurality of positive conductors at the second smart unit.

13. The direct current electrical circuit set forth in claim 12 comprising:

a muliplexer disposed within the second smart unit which receives and multiplexs a plurality of second voltages of the plurality of positive conductors; and

wherein a multiplexed voltage signal is sent from the adding multiplexer to a comparator disposed within the first smart unit.