Dynamic Detection of Decomposition Gases in Eco-Friendly\nC<sub>5</sub>F<sub>10</sub>O Gas-Insulated Power Equipment by Fiber-Enhanced\nRaman Spectroscopy

Dynamic\ndetection of multiple C<sub>5</sub>F<sub>10</sub>O decomposition\ngases can more comprehensively and effectively evaluate the operating\nstatus of eco-friendly gas-insulated power equipment (GIPE), which\nis a technical support for promoting the construction of eco-friendly,\nlow-carbon energy power systems. In this article, we propose a silicon\nnoise suppression fiber-enhanced Raman spectroscopy (FERS) technique\nand design a FERS sensing system for the dynamic detection of multiple\nC<sub>5</sub>F<sub>10</sub>O decomposition gases. Benefiting from\nthe effective hybrid silicon noise filtering technology, the spectrum\nnoise of FERS can be suppressed by 90% and the system detection sensitivity\ncan be improved by 4.22 times. Utilizing a 2 m-long antiresonant hollow-core\nfiber, the system achieved detection limits of 1.34 and 1.44 ppmv\nfor CF<sub>4</sub> and CO<sub>2</sub>, respectively, under the conditions\nof a laser power of 200 mW, a pressure of 0.5 MPa, and a measurement\ntime of 120 s. Afterward, combining sample gas and density functional\ntheory simulation, the characteristic peak positions for quantitative\nanalysis of C<sub>5</sub>F<sub>10</sub>O decomposition gas were determined\nas follows: CF<sub>4</sub>: 906 cm<sup>–1</sup>, CO<sub>2</sub>: 1388 cm<sup>–1</sup>, C<sub>5</sub>F<sub>10</sub>O: 759\ncm<sup>–1</sup>, CF<sub>2</sub>O: 965 cm<sup>–1</sup>, CF<sub>3</sub>H: 1117 cm<sup>–1</sup>, C<sub>2</sub>F<sub>4</sub>: 517 cm<sup>–1</sup>, C<sub>2</sub>F<sub>6</sub>:\n807 cm<sup>–1</sup>, C<sub>3</sub>F<sub>6</sub>: 767 cm<sup>–1</sup>, C<sub>3</sub>F<sub>8</sub>: 780 cm<sup>–1</sup>, C<sub>3</sub>F<sub>7</sub>H: 857 cm<sup>–1</sup>, and C<sub>4</sub>F<sub>10</sub>: 770 cm<sup>–1</sup>. Finally, the sensing\nsystem conducted dynamic measurements of the partial discharge decomposition\ngases of the C<sub>5</sub>F<sub>10</sub>O GIPE for 5 days with a 2\nh measurement interval. The content trends of C<sub>5</sub>F<sub>10</sub>O and decomposition gases CF<sub>4</sub>, CO<sub>2</sub>, C<sub>3</sub>F<sub>6</sub>, and C<sub>3</sub>F<sub>7</sub>H were obtained. These\nresults fully demonstrate the capability of FERS technology for dynamically\ndetecting the decomposition gases of the C<sub>5</sub>F<sub>10</sub>O GIPE.