Dynamic Detection of Decomposition Gases in Eco-Friendly C₅F₁₀O Gas-Insulated Power Equipment by Fiber-Enhanced Raman Spectroscopy

Abstract

Dynamic detection of multiple C5F10O decomposition gases can more comprehensively and effectively evaluate the operating status of eco-friendly gas-insulated power equipment (GIPE), which is a technical support for promoting the construction of eco-friendly, low-carbon energy power systems. In this article, we propose a silicon noise suppression fiber-enhanced Raman spectroscopy (FERS) technique and design a FERS sensing system for the dynamic detection of multiple C5F10O decomposition gases. Benefiting from the effective hybrid silicon noise filtering technology, the spectrum noise of FERS can be suppressed by 90% and the system detection sensitivity can be improved by 4.22 times. Utilizing a 2 m-long antiresonant hollow-core fiber, the system achieved detection limits of 1.34 and 1.44 ppmv for CF4 and CO2, respectively, under the conditions of a laser power of 200 mW, a pressure of 0.5 MPa, and a measurement time of 120 s. Afterward, combining sample gas and density functional theory simulation, the characteristic peak positions for quantitative analysis of C5F10O decomposition gas were determined as follows: CF4: 906 cm–1, CO2: 1388 cm–1, C5F10O: 759 cm–1, CF2O: 965 cm–1, CF3H: 1117 cm–1, C2F4: 517 cm–1, C2F6: 807 cm–1, C3F6: 767 cm–1, C3F8: 780 cm–1, C3F7H: 857 cm–1, and C4F10: 770 cm–1. Finally, the sensing system conducted dynamic measurements of the partial discharge decomposition gases of the C5F10O GIPE for 5 days with a 2 h measurement interval. The content trends of C5F10O and decomposition gases CF4, CO2, C3F6, and C3F7H were obtained. These results fully demonstrate the capability of FERS technology for dynamically detecting the decomposition gases of the C5F10O GIPE.