{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2025,12,18]],"date-time":"2025-12-18T13:40:20Z","timestamp":1766065220475,"version":"build-2065373602"},"reference-count":22,"publisher":"MDPI AG","issue":"18","license":[{"start":{"date-parts":[[2021,9,13]],"date-time":"2021-09-13T00:00:00Z","timestamp":1631491200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Sensors"],"abstract":"<jats:p>Power transformers are central elements of power transmission systems and their deterioration can lead to system failures, causing major disruptions in service. Catastrophic failures can occur, posing major environmental hazards due to fires, explosions, or oil spillage. Early fault detection can be accomplished or estimated using electrical sensors or a chemical analysis of oil or gas samples. Conventional methods are incapable of real-time measurements with a low electrical noise due to time-consuming analyses or susceptibility to electromagnetic interference. Optical fiber sensors, passive elements that are immune to electromagnetic noise, are capable of structural monitoring by being enclosed in power transformers. In this work, optical fiber sensors embedded in 3D printed structures are studied for vibration monitoring. The fiber sensor is encapsulated between two pressboard spacers, simulating the conditions inside the power transformer, and characterized for vibrations with frequencies between 10 and 800 Hz, with a constant acceleration of 10 m\/s2. Thermal aging and electrical tests are also accomplished, aiming to study the oil compatibility of the 3D printed structure. The results reported in this work suggest that structural monitoring in power transformers can be achieved using optical fiber sensors, prospecting real-time monitoring.<\/jats:p>","DOI":"10.3390\/s21186127","type":"journal-article","created":{"date-parts":[[2021,9,14]],"date-time":"2021-09-14T03:46:14Z","timestamp":1631591174000},"page":"6127","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":15,"title":["Optical Fiber Sensors for Structural Monitoring in Power Transformers"],"prefix":"10.3390","volume":"21","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-0463-9894","authenticated-orcid":false,"given":"Catarina S.","family":"Monteiro","sequence":"first","affiliation":[{"name":"Department of Engineering Physics, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Centre for Applied Photonics, Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]},{"given":"Ant\u00f3nio V.","family":"Rodrigues","sequence":"additional","affiliation":[{"name":"Department of Engineering Physics, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Centre for Applied Photonics, Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]},{"given":"Duarte","family":"Viveiros","sequence":"additional","affiliation":[{"name":"Department of Engineering Physics, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Department of Physics and Astronomy, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-8128-3991","authenticated-orcid":false,"given":"Cassiano","family":"Linhares","sequence":"additional","affiliation":[{"name":"Efacec Energia, M\u00e1quinas e Equipamentos El\u00e9ctricos, S.A., Apartado 1018, 4466-952 Porto, Portugal"}]},{"given":"H\u00e9lder","family":"Mendes","sequence":"additional","affiliation":[{"name":"Efacec Energia, M\u00e1quinas e Equipamentos El\u00e9ctricos, S.A., Apartado 1018, 4466-952 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7555-361X","authenticated-orcid":false,"given":"Susana O.","family":"Silva","sequence":"additional","affiliation":[{"name":"Centre for Applied Photonics, Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]},{"given":"Paulo V. S.","family":"Marques","sequence":"additional","affiliation":[{"name":"Department of Engineering Physics, Faculty of Engineering, University of Porto, R. Dr. Roberto Frias, s\/n, 4200-465 Porto, Portugal"},{"name":"Department of Physics and Astronomy, Faculty of Science, University of Porto, Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]},{"given":"S\u00e9rgio M. O.","family":"Tavares","sequence":"additional","affiliation":[{"name":"Efacec Energia, M\u00e1quinas e Equipamentos El\u00e9ctricos, S.A., Apartado 1018, 4466-952 Porto, Portugal"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7680-1056","authenticated-orcid":false,"given":"Orlando","family":"Fraz\u00e3o","sequence":"additional","affiliation":[{"name":"Centre for Applied Photonics, Institute for Systems and Computer Engineering, Technology and Science (INESC TEC), Rua do Campo Alegre, 687, 4150-179 Porto, Portugal"}]}],"member":"1968","published-online":{"date-parts":[[2021,9,13]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"305","DOI":"10.1016\/S0030-3992(01)00022-6","article-title":"Optical fiber sensor-based detection of partial discharges in power transformers","volume":"33","author":"Deng","year":"2001","journal-title":"Opt. 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