Onboard electrical current sensing system

• US 8,264,215 B1
• Filed: 12/10/2009
• Issued: 09/11/2012
• Est. Priority Date: 12/10/2009
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Robb, Andrew M., Kovach, Daniel James
• Primary Examiner(s): Assouad, Patrick
• Assistant Examiner(s): BROWN, LAMARR A
• Application Number:
  US12/635,576
• Time in Patent Office: 1,006 Days
• Field of Search: 324/117.H, 324/117.R, 324/126, 324/72, 324/555, 324127-129, 324/72.5, 307/9.1, 307/11, 307 18- 20, 307/24
• US Class Current: 324/72
• CPC Class Codes: B64D 2045/0085 Devices for aircraft health monitoring, e.g. monitoring flutter or vibration
• CPC Class Codes: B64D 45/02 Lightning protectors; Static dischargers in general H01T
• CPC Class Codes: G01R 29/0842 Measurements related to lightning, e.g. measuring electric disturbances, warning systems
• CPC Class Codes: G01R 31/008 on air- or spacecraft, railway rolling stock or sea-going vessels
• CPC Class Codes: H02G 13/00 Installations of lightning conductors; Fastening thereof to supporting structure
• CPC Class Codes: H02G 13/60 Detecting; Measuring; Sensing; Testing; Simulating

Abstract

Electrical currents are detected and analyzed across structural members in a structural joint, such as a fastener of a vehicle. In some aspects, printed circuit boards etched with Rogowski coil circuits are inserted proximate the structural members in the structural joint. The Rogowski coil circuits may detect an electrical current as it flows through the structural joint. An integrator may integrate a transient current to generate an output signal, such as when the vehicle is subjected to an electrical charge. The output signal may be transmitted to an Integrated Vehicle Health Management (IVHM) system for analysis. In various aspects, the IVHM system may enable recording and reporting of various aspects of the current to enable maintenance, inspection, or real time/near real time health assessment of the vehicle.

Claims

1. A method of sensing an onboard electrical current, the method comprising:

receiving a current through one or more structural members of a structural joint;

detecting the current via a plurality of Rogowski coil circuits of the structural joint;

integrating the current from the plurality of Rogowski coil circuits into an output signal;

transmitting the output signal to an Integrated Vehicle Health Management (IVHM) system; and

recording, via the IVHM system, a log of the current including a magnitude of the current and a tag identifying a coil circuit detecting the current; and

inserting at least one printed circuit board etched with the plurality of Rogowski coil circuits into the structural joint.

2. The method of claim 1, wherein the structural joint joins two elements of an aircraft, wherein at least one of the two elements is a composite structure.

3. The method of claim 1, wherein the current is received from at least one of a lightning strike or an aircraft certification test.

4. The method of claim 1, further comprising:

comparing the output signal from the plurality of Rogowski coil circuits to a characteristic performance curve to determine a severity of the current; and

outputting the severity of the current as one of an audible or textual message.

5. The method of claim 1, wherein the printed circuit board includes a gain control system to either amplify or attenuate a magnitude of the current.

6. An onboard current sensing system, comprising:

an electrical sensor to detect a flow of electrical currents;

an integrator to integrate the flow of electrical currents to an analog signal;

an analog-to-digital converter to convert the analog signal to a digital signal; and

an Integrated Vehicle Health Management (IVHM) system to receive the digital signal and record a log of attributes of the flow of electrical currents including a magnitude of the electrical currents and a tag identifying a source of the electrical currents, wherein the electrical sensor is a Rogowski coil circuit capable of measuring a current of the flow of electrical currents in a range from 200 mA to 200 kA.

7. The electricity sensing system of claim 6, wherein the electrical sensor is a voltage probe capable of measuring a voltage of the flow of electrical currents in a range from 50 volts to 5000 volts.

8. The electricity sensing system of claim 6, wherein the integrator is embedded on the Rogowski coil circuit.

9. The electricity sensing system of claim 6, wherein the electrical sensor is positioned between two structures of an aircraft, wherein at least one of the two structures is a composite structure.

10. The electricity sensing system of claim 9, wherein the electrical sensor includes a gain control system to:

(1) amplify a magnitude of the electrical currents when the aircraft is in a testing status, and (2) attenuate the electrical currents when the aircraft is in an operational status.

11. The electricity sensing system of claim 6, wherein the IVHM system further compares the digital signal to a characteristic performance curve to determine a severity of the electrical currents.

12. The electricity sensing system of claim 11, wherein the electrical sensor generates the characteristic performance curve.

13. The electricity sensing system of claim 6, wherein the electrical sensor detects the flow of electrical currents as a transient current.

14. An Integrated Vehicle Health Management (IVHM) system, comprising:

an uncored transformer positioned between two structures to detect an electrical current, wherein the uncored transformer comprises a Rogowski coil circuit capable of measuring a current of the flow of electrical currents in a range from 200 mA to 200 kA;

an analysis module to determine a magnitude and flow direction of the electrical current;

a communications module to output the magnitude and flow direction of the electrical current; and

a database interface module to store data associated with the electrical current, the data stored in a data log.

15. The IVHM system of claim 14, wherein the analysis module compares the electrical current to a characteristic performance curve to determine a severity of the current.

16. The IVHM system of claim 15, wherein the uncored transformer generates the characteristic performance curve.

17. The IVHM system of claim 14, wherein at least one of the two structures is a composite structure of an aircraft.

18. The IVHM system of claim 14, wherein the database interface module stores the magnitude and flow direction of the electrical current and a structural location of one or more areas affected by the electrical current in the data log.