Research on the detection of SF₆ decomposition products based on non-resonant photoacoustic spectroscopy

Abstract

Using a low-cost infrared light source and a selection of narrowband filters, the non-resonant photoacoustic device is able to detect CO, SO2 and CF4 in SF6 down to a few ppm.

Highly sensitive photoacoustic multicomponent gas sensor for SF6 decomposition online monitoring

“…For example, H. Heise et al [24] and X. Zhang et al [25] employed Fourier-transform infrared (FTIR) spectroscopy technology to perform quantitative multicomponent gas analysis for the SF 6 decompositions. J. Luo et al [26] employed a non-resonant photoacoustic spectroscopy sensor to detect SO 2 , CO and CF 4 by using a broadband light source within 4-8 μm wavelength range. However, most by-products have cross-interference absorption with pure SF 6 in the mid-infrared (MIR) region.…”

Highly sensitive and selective CO sensor using a 233 μm diode laser and wavelength modulation spectroscopy

“…The online detection for SF 6 decomposition is an effective means for fault early warning of electric power transmission equipment, which is based on the fact that SF 6 can be decomposed in the case of superheating and a partial discharge (PD) caused by latent inner insulation defects. In this process, various sulfur-containing, fluorinecontaining compounds, such as SF 4 , HF, SO 2 F 2 , SOF 2 , SO 2 , CO 2 ,CO, SF 4 , are generated via a reaction between water, oxygen, metal vapor or other impurities [1][2][3][4][5]. These decomposition gases can be employed as indicator gases to locate and identify fault types and their locations.…”

Highly Sensitive H2S Detection for SF6 Decomposition Based on Photoacoustic Spectroscopy

“…Sulfur hexafluoride (SF 6 ) gas has an excellent insulating property, which is widely used as an insulating medium in electric power systems, such as in gas-insulated switchgear (GIS), gas circuit breakers (GCBs), transformers (GIT) and transmission pipes (GIL) [1]. Normally, SF 6 is hard to decompose, but with successive reactions with contaminants such as water vapor and oxygen, various chemical byproducts, such as H 2 S, SO 2 , SF 4 , CO, CF 4 and SOF 2 are generated, which can chemically attack solid insulation materials and accelerate insulation aging and eventually lead to power system failure.…”