Online fiber optic sensor for detecting partial discharge and similar events in large utility station transformers and the like

• US 7,071,701 B2
• Filed: 03/05/2004
• Issued: 07/04/2006
• Est. Priority Date: 03/05/2004
• Status: Active Grant

• Current Assignee: New Jersey Institute of Technology, Public Service Electric and Gas Company (Public Service Enterprise Group Incorporated)
• Original Assignee: New Jersey Institute of Technology
• Inventors: Wang, Xiaodong, Li, Baoqing, Roman, Harry T., Farmer, II, Kenneth Rudolph
• Primary Examiner(s): Deb, Anjan
• Assistant Examiner(s): Dole, Timothy J.
• Application Number:
  US10/794,177
• Publication Number:
  US 20050194979A1
• Time in Patent Office: 851 Days
• Field of Search: 324/536
• US Class Current: 324/536
• CPC Class Codes: G01R 31/1209 using acoustic measurements acoustic measurements G01H3/00
• CPC Class Codes: G01R 31/1272 of cable, line or wire insulation, e.g. using partial discharge measurements locating faults in cables G01R31/083

Abstract

An approved method and apparatus for detecting partial discharge events within a transformer comprises asserting a MEMS acoustical probe through the wall of the transformer to optically measure partial discharge events. In an enhanced embodiment, temperature compensation is also possible, and detection may be confirmed via an independent electromagnetic or other sensor.

Claims

1. Apparatus for detecting partial discharge events comprising a detection circuit for detecting acoustical signatures resulting from a partial discharge event, a plurality of stored signatures for comparing said acoustical signatures to said stored signatures, and an output for signaling detection of a partial discharge event when said detected acoustical signature matches at least one stored signature wherein said at least one stored signature is selected for comparison to said detected signature based upon temperature of an environment in which said apparatus is operating.

2. Apparatus of claim 1 further comprising a temperature sensor.

3. Apparatus of claim 2 further comprising plural detection circuits for detecting said event, and a processor for trigonometrically locating said event.

4. The apparatus of claim 2 wherein said temperature sensor is integrated with said detection circuit.

5. The apparatus of claim 1 further comprising an electromagnetic sensor for detecting partial discharge events, and a processor for comparing signals detected at said electromagnetic sensor to signals detected at said detection circuit.

6. The apparatus of claim 3 wherein said detection circuit is an optical detection circuit.

7. The apparatus of claim 1 wherein plural detection circuits are integrated into a single probe.

8. The apparatus of claim 7 wherein said plural detection circuits comprise at least one circuit for detecting electromagnetic energy and at least one circuit for detecting acoustic energy.

9. The apparatus of claim 8 further comprising at least one temperature sensor.