Development of an identification system for location of free metallic particles in GIS based on analysis of Lamb waves

• Published in: Electrical engineering in Japan Vol. 167; no. 3; pp. 28 - 35
• Main Authors: Kozako, Masahiro, Ohtsuka, Shinya, Kaneko, Shuhei, Okabe, Shigemitsu, Hikita, Masayuki
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.05.2009
• Subjects: free metallic particle; GIS; insulation diagnosis; Lamb waves; location identification system; wavelet transform
• ISSN: 0424-7760; 1520-6416
• DOI: 10.1002/eej.20676

We investigated propagation properties of Lamb waves in a gas‐insulated switchgear (GIS) tank to diagnose insulation performance of GIS. The acoustic signals excited by a free metallic particle colliding with the tank sheath were measured using AE sensors. The wavelet transform was applied to decompose the wave data into its time–frequency components. As a result, difference of propagation properties of Lamb waves is clearly seen with different sizes of GIS tank. Based on the characteristics of Lamb waves, algorithms for location identification of a free metallic particle were examined in model GIS using two AE sensors. Herein, we propose a new system for location identification of a free metallic particle in GIS. Moreover, it is verified that the new identification system is suitable as a diagnostic technique for GIS. © 2009 Wiley Periodicals, Inc. Electr Eng Jpn, 167(3): 28–35, 2009; Published online in Wiley InterScience (www.interscience.wiley.com). DOI 10.1002/eej.20676