抄録
We have investigated propagation properties of Lamb waves and motion characteristic of free moving metallic particle in gas insulated switchgear (GIS) tank to diagnose insulation performance of GIS. We have proposed a new identification technique of the defect location in GIS based on the time-frequency analysis of the Lamb waves using the Wavelet Transform. In this paper, we measured the acoustic signals excited by a metallic particle colliding with the tank sheath. Furthermore, we measured the moving particle under the high electric field in GIS using a high speed video camera. As a result, it was examined that the relationship between maximum lifting height and the flight time during subsequent impacts of a moving particle. Moreover, we estimated particle size based on propagation properties of Lamb waves.
