Highly sensitive multi-pass cavity enhanced Raman spectroscopy with novel polarization filtering for quantitative measurement of SF6 decomposed components in gas-insulated power equipment

Trace Analysis of C4F7N Insulating Gas Mixtures by Spontaneous Raman Spectroscopy and Gas Chromatography

“…Sulfur hexafluoride (SF 6 ) is among the most popular insulating gases and is employed in a variety of industries. Its most common application is as an arc quenching gas in high-voltage electrical switchgear systems due to its optimal dielectric properties and very stable nature derived from its octahedral geometry. − However, SF 6 is categorized as a highly potent greenhouse gas with a global warming potential (GWP) of 23,500. − SF 6 is now reported to have an atmospheric lifespan of 850 years, with electron attachment identified as the primary removal process, although a lifespan of 3200 years and UV radiation-triggered photolysis as the main removal mechanism were previously reported by the Intergovernmental Panel on Climate Change (IPCC). , There is thus a need for an appropriate replacement gas that has properties similar to those of SF 6 but without the environmental impact.…”

Raman signal enhancement for gas detection using a dual near-concentric cavities group

“…It has the advantages of simultaneous detection of multicomponents, a large detection concentration range, being a simple device, and in situ detection. Based on the above advantages, this technology has been applied to hazardous materials detection [2,3] , gas composition analysis [4][5][6] , environmental monitoring [6][7][8] , and medical diagnosis [9,10] . However, the signal intensity of spontaneous Raman scattering is weak and susceptible to fluorescence interference [11] , leading to low detection sensitivity.…”

Analysis of SF6 decomposed products by fibre‐enhanced Raman spectroscopy for gas‐insulated switchgear diagnosis

“…However, the application of Raman spectroscopy for trace gas sensing is astricted by the weak inelastic scattering process and low molecular density of gases. Advanced methods using multipass cells (MPC) [18][19][20] or high fineness Fabry-Perot (F-P) cavities [21][22][23][24][25] are developed for Raman signal enhancement and have pushed the limits of detection (LODs) down to extremely low levels. However, these methods have little tolerance for cavity-mirror alignment and cavity-length control, necessitating precision mechanical components and frequencylocking techniques (for F-P cavities) that increase the size and fabrication complexity.…”