Motion and size estimation of a free moving metallic particle in GIS based on propagation properties of acoustic waves

Abstract

SUMMARYWe have investigated the propagation properties of Lamb waves and motion characteristic of free moving metallic particle in a gas-insulated switchgear (GIS) tank to diagnose the insulation performance of GIS. We have proposed a new identification technique for 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 particles under a high electric field in GIS using a high-speed video camera. As a result, we examined the relationship between maximum lifting height and the flight time during subsequent impacts of a moving particle. Moreover, we estimated particle size based on the propagation properties of Lamb waves.

Partial discharge detection by extracting UHF signal from inner grading electrode of insulating spacer in GIS

“…The gas-insulated switchgear (GIS) is widely used as the main power equipment in the electric power system due to its high reliability and compactness [1][2][3]. The insulation breakdown of the GIS usually starts from partial discharge (PD), which is caused by the aging of insulating materials or the defects caused during the manufacturing process and operation.…”