ELECTROMAGNETIC EFFECT TESTING

• US 20150260775A1
• Filed: 03/12/2014
• Published: 09/17/2015
• Est. Priority Date: 03/12/2014
• Status: Active Grant

• Current Assignee: The Boeing Co.
• Original Assignee: The Boeing Co.
• Inventors: Robb, Andrew M., Bommer, Jason P., Yuen, Felix D.
• Granted Patent: US 9,739,818 B2
• Time in Patent Office: Days
• US Class Current: 1/1
• CPC Class Codes: B64D 45/02 Lightning protectors; Static dischargers in general H01T
• CPC Class Codes: B64F 5/60 Testing or inspecting aircraft components or systems
• CPC Class Codes: G01R 15/181 using coils without a magnetic core, e.g. Rogowski coils
• CPC Class Codes: G01R 19/0092 measuring current only all subgroups of G01R19/00 take precedence
• CPC Class Codes: G01R 29/0842 Measurements related to lightning, e.g. measuring electric disturbances, warning systems
• CPC Class Codes: G01R 31/001 Measuring interference from external sources to, or emission from, the device under test, e.g. EMC, EMI, EMP or ESD testing measuring electromagnetic fields G01R29/08; circuits for generating HV pulses in dielectric strength testing G01R31/14
• CPC Class Codes: G01R 31/008 on air- or spacecraft, railway rolling stock or sea-going vessels
• CPC Class Codes: H04Q 9/00 Arrangements in telecontrol or telemetry systems for selectively calling a substation from a main station, in which substation desired apparatus is selected for applying a control signal thereto or for obtaining measured values therefrom

Abstract

A device comprises a circuit board, a Rogowski coil on the circuit board, persistent data storage on the circuit board, and a control circuit on the circuit board for collecting values representing current sensed by the coil, and storing the values in the persistent memory.

Claims

1. A device comprising:

a circuit board;

a Rogowski coil on the circuit board;

persistent data storage on the circuit board; and

a control circuit on the circuit board for collecting values representing current sensed by the coil, and storing the values in the persistent memory.

2. The device of claim 1, wherein the circuit board is a multi-layer printed circuit board;

and wherein the Rogowski coil is formed in multiple layers of the circuit board.

3. The device of claim 1, wherein the control circuit includes an analog integrator responsive to the coil.

4. The device of claim 1, further comprising a ferromagnetic shield covering the data storage and the control circuit.

5. The device of claim 1, wherein the circuit board has a length of several inches.

6. The device of claim 1, wherein the control circuit includes a controller configured to detect an electromagnetic effect (EME) event, and store the values for a first period after the EME event has been detected.

7. The device of claim 6, wherein the control circuit is further configured to construct a full current waveform for those values stored during a second period immediately preceding the EME event and those values stored during the first period, which immediately followed the EME event.

8. The device of claim 7, wherein the first period is about 50 microseconds, and the second period is between 300 and 450 microseconds.

9. The device of claim 7, wherein the control circuit is configured to transmit the full current waveform in response to an external query.

10. The device of claim 1, further comprising a wireless transmitter for transmitting the full current waveform.

11. A system for analyzing a structure during an electromagnetic effect (EME) event, the system comprising a plurality of the devices of claim 1 fastened to the structure.

12. The system of claim 11, further comprising a computer programmed to query the devices to collect information about current flowing through the structure during the EME event, the devices queried after the EME event has ended.

13. The system of claim 12, wherein the devices includes wireless transmitters for communicating wirelessly with the computer.

14. The system of claim 12, wherein the computer is further programmed to process the collected information to map a path of EME current that flowed through the structure during the EME event.

15. A current sensing device comprising:

an electromagnetic effect (EME) current sensor; and

a control circuit for buffering values from the current sensor, using the values to detect an EME event, and constructing a full current waveform from those values buffered during a first period immediately preceding the EME event and a period immediately following the EME event.

16. The device of claim 15, wherein the current sensor includes a Rogowski coil.

17. The device of claim 15, further comprising persistent data storage, wherein the controller saves the full current waveform in the persistent data storage and outputs the full waveform upon request.

18. A method comprising:

fastening a plurality of circuit boards to a structure with fasteners, each circuit board including a Rogowski coil surrounding one of the fasteners;

collecting sensor measurements from the coils and storing the measurements on the circuit boards;

subjecting the structure to an electromagnetic effect (EME) event while continuing to collect additional sensor measurements from the coils and store the additional sensor measurements on the circuit boards; and

retrieving the stored measurements from the circuit boards after the EME event has ended.

19. The method of claim 18, further comprising detecting the EME event, and constructing full current waveforms from the measurements, wherein each waveform is constructed from those measurements buffered during a first period immediately preceding the detected EME event and a period immediately following the detected EME event.

20. The method of claim 19, wherein the waveforms are outputted after the EME event has ended.