Terahertz time-domain spectroscopy detection of metal foreign bodies in GIS equipment

Metallic foreign bodies often appear in Gas-insulated Switchgear (GIS). Metallic foreign bodies can cause great harm to the insulation performance of GIS equipment. Therefore, it is very necessary to detect metal foreign bodies in GIS equipment. In this paper, terahertz time-domain spectroscopy is used to measure the three insulating materials of epoxy resin, silicon rubber, ceramics and the mixture of the three materials experimentally. Then obtain the time-domain, frequency-domain, and absorption spectra of the four groups of materials. On this basis, aluminum powder and copper powder were added to the four sets of insulating material samples, and the time domain, frequency domain, and absorption spectra of the materials after adding aluminum powder and copper powder were obtained by using terahertz time-domain spectroscopy technology. The experimental results show that after adding the metal powder to the insulating material, the time domain, frequency domain and absorption spectrogram of the material will be significantly reduced. The terahertz technology can quickly and accurately detect whether there are metal foreign bodies in the GIS equipment, thereby ensuring the safe operation of the power grid.