Detection and monitoring of partial discharge of a power line

• US 7,863,905 B2
• Filed: 03/25/2009
• Issued: 01/04/2011
• Est. Priority Date: 07/07/2006
• Status: Active Grant

• Current Assignee: Ericsson, Inc. (Telefonaktiebolaget LM Ericsson)
• Original Assignee: Ambient S A
• Inventors: Cern, Yehuda
• Primary Examiner(s): He; Amy
• Application Number:
  US12/383,520
• Publication Number:
  US 20090189594A1
• Time in Patent Office: 650 Days
• Field of Search: 324/536
• US Class Current: 324/536
• CPC Class Codes: G01R 31/1272 of cable, line or wire insulation, e.g. using partial discharge measurements locating faults in cables G01R31/083
• CPC Class Codes: H04B 2203/5495 having measurements and testing channel
• CPC Class Codes: H04B 3/54 Systems for transmission via power distribution lines

Abstract

There is provided a method that includes (a) acquiring a first spectral component of a single noise pulse on a power line, and a second spectral component of the single noise pulse, (b) determining that the single noise pulse is synchronous with a power voltage on the power line, (c) determining a first magnitude of the first spectral component, (d) determining a second magnitude of the second spectral component, and (e) determining a condition of the power line from the first and second magnitudes. There is also provided a system that employs the method.

Claims

1. A method comprising:

acquiring a first spectral component of a single noise pulse on a power line, and a second spectral component of said single noise pulse;

determining that said single noise pulse is synchronous with a power voltage on said power line;

determining a first magnitude of said first spectral component;

determining a second magnitude of said second spectral component; and

determining a condition of said power line from said first and second magnitudes.

2. The method of claim 1, wherein said determining said condition comprises determining a difference between said first and second magnitudes.

3. The method of claim 1,

wherein said single noise pulse is a first single noise pulse,

wherein said first and second spectral components are members of a first plurality of spectral components,

wherein said method further comprises:

acquiring a second plurality of spectral components of a second single noise pulse on said power line, and

determining, from said second plurality of spectral components, that said second single noise pulse is also synchronized to said power voltage on said power line.

4. The method of claim 1,

wherein said acquiring comprises routing a signal derived from said single noise pulse to a first filter and a second filter having respective inputs in parallel with one another,

wherein said first filter passes said first spectral component, and

wherein said second filter passes said second spectral component.

5. A system comprising:

a coupler that couples a noise signal from a power line; and

a detector that;

receives said noise signal;

receives a signal having a fixed phase relationship with a power frequency voltage on said power line;

acquires a first spectral component of a single noise pulse in said noise signal, and a second spectral component of said single noise pulse;

determines that said single noise pulse is synchronous with said power frequency voltage;

determines a first magnitude of said first spectral component;

determines a second magnitude of said second spectral component; and

determines a condition of said power line from said first and second magnitudes.