{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T18:29:31Z","timestamp":1786472971656,"version":"build-2736575974"},"reference-count":33,"publisher":"Public Library of Science (PLoS)","issue":"8","license":[{"start":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T00:00:00Z","timestamp":1786406400000},"content-version":"vor","delay-in-days":0,"URL":"http:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"State Grid Fujian Electric Power Company Science and Technology Project","award":["52130A250004"],"award-info":[{"award-number":["52130A250004"]}]}],"content-domain":{"domain":["www.plosone.org"],"crossmark-restriction":false},"short-container-title":["PLoS One"],"abstract":"<jats:p>Conventional detection of metal particle defects in gas-insulated switchgear (GIS) mainly relies on piezoelectric (PZT) sensors, which are inadequate for distributed monitoring in modern power equipment. Although interferometric optical fiber sensors offer high sensitivity for GIS partial discharge detection, they are generally limited to single-point measurements. To address this issue, this study proposes a multiplexing method for optical fiber acoustic emission sensors based on optical frequency-scanning in a Michelson interferometric configuration. By introducing high-frequency carriers through optical frequency modulation and separating channels via bandpass filtering, the proposed method preserves the high sensitivity of conventional single-point interferometric sensors and extends it to multiplexed sensing, enabling frequency-division multiplexing of multiple sensors using a single demodulation system. Experiments on a 126 kV GIS with four sensing units demonstrate that the proposed system can effectively detect discharge signals and identify the defective cavity. This work provides a promising approach for distributed GIS condition monitoring.<\/jats:p>","DOI":"10.1371\/journal.pone.0355959","type":"journal-article","created":{"date-parts":[[2026,8,11]],"date-time":"2026-08-11T17:32:16Z","timestamp":1786469536000},"page":"e0355959","update-policy":"https:\/\/doi.org\/10.1371\/journal.pone.corrections_policy","source":"Crossref","is-referenced-by-count":0,"title":["Distributed optical fiber sensing for metal particle defect detection in GIS via frequency-swept interferometry"],"prefix":"10.1371","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-0148-2476","authenticated-orcid":true,"given":"Xu","family":"Zhixin","sequence":"first","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Zhao","family":"Xincheng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Li","family":"Chaohui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Su","family":"Honghui","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xie","family":"Peng","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Yang","family":"Liusong","sequence":"additional","affiliation":[],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"340","published-online":{"date-parts":[[2026,8,11]]},"reference":[{"issue":"1","key":"pone.0355959.ref001","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1002\/etep.582","article-title":"Ultra high\u2010voltage gas\u2010insulated switchgear \u2013 a technology milestone","volume":"22","author":"U Riechert","year":"2011","journal-title":"Int Trans Elec Energy Syst"},{"issue":"6","key":"pone.0355959.ref002","doi-asserted-by":"crossref","first-page":"3724","DOI":"10.1109\/TPWRD.2020.3048789","article-title":"An Elimination Method for an Emergency Situation in Gas-Insulated Switchgear in Power Grids","volume":"36","author":"M Borecki","year":"2021","journal-title":"IEEE Trans Power Delivery"},{"issue":"6","key":"pone.0355959.ref003","doi-asserted-by":"crossref","first-page":"2165","DOI":"10.1109\/TDEI.2013.6678866","article-title":"Risk assessment on defects in GIS based on PD diagnostics","volume":"20","author":"U Schichler","year":"2013","journal-title":"IEEE Trans Dielect Electr Insul"},{"issue":"5","key":"pone.0355959.ref004","doi-asserted-by":"crossref","first-page":"2017","DOI":"10.1109\/TDEI.2022.3201438","article-title":"Discharge Characteristics of Insulation Defects in GIS Under AC\/LI Superimposed Voltage","volume":"29","author":"X Li","year":"2022","journal-title":"IEEE Trans Dielect Electr Insul"},{"issue":"2","key":"pone.0355959.ref005","doi-asserted-by":"crossref","first-page":"757","DOI":"10.1109\/TPWRD.2022.3197221","article-title":"Metal Particle Movement and Induced Insulator Flashover Under Impact Vibration Generated By Switching Operation in GIS","volume":"38","author":"X Li","year":"2022","journal-title":"IEEE Trans Power Delivery"},{"issue":"1","key":"pone.0355959.ref006","doi-asserted-by":"crossref","first-page":"187","DOI":"10.1109\/TPWRD.2021.3055533","article-title":"Discharge Characteristics and Detectability of Metal Particles on the Spacer Surface in Gas-Insulated Switchgears","volume":"37","author":"X Li","year":"2022","journal-title":"IEEE Trans Power Delivery"},{"issue":"4","key":"pone.0355959.ref007","doi-asserted-by":"crossref","first-page":"2977","DOI":"10.1109\/TPWRD.2023.3276197","article-title":"Distributed Detection and Acoustic Emission Waveform Retrieval of Cable Joint Partial Discharge","volume":"38","author":"W Qin","year":"2023","journal-title":"IEEE Trans Power Delivery"},{"key":"pone.0355959.ref008","doi-asserted-by":"crossref","unstructured":"Han X, Li J, Sun W, et al. Simulation study on propagation characteristics of optical signals excited by partial discharge in GIS. 2020 IEEE International Conference on High Voltage Engineering and Application (ICHVE). 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