Evaluation of Insulation Performance in Oil-Immersed Power Equipment Under Low Temperatures

Evaluation of Insulation Performance in Oil-Immersed Power Equipment Under Low Temperatures | Research Square window.SnipcartSettings = { analytics: { enabled: false } }; (function() { var accessVector = localStorage.getItem('access_vector') || ''; window.dataLayer = window.dataLayer || []; if (accessVector) { window.dataLayer.push({ user: { profile: { profileInfo: { snid: accessVector } } } }); } })(); (function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start':new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0],j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src='https://www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f);})(window,document,'script','dataLayer','GTM-K279D39R'); Browse Preprints In Review Journals COVID-19 Preprints AJE Video Bytes Research Tools Research Promotion AJE Professional Editing AJE Rubriq About Preprint Platform In Review Editorial Policies Our Team Advisory Board Help Center Sign In Submit a Preprint Cite Share Download PDF Article Evaluation of Insulation Performance in Oil-Immersed Power Equipment Under Low Temperatures Raheel Ahmed, Ji Liu, Mingze Zhang, Xianhao Fan This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6616199/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 15 You are reading this latest preprint version Abstract To investigate the dielectric properties of oil-impregnated paper and transformer oil at low temperature conditions that effect the performance of power equipment situated at cold climatic zone. This research focuses on the effects of aging and temperature on the dielectric properties, moisture content, viscosity, conductivity of transformer oil and oil-paper insulation. Frequency Domain Spectroscopy method is used to determine dielectric loss, and real and imaginary permittivity over a temperature range of 10°C to -40°C, where the results indicate that aging drastically changes the dielectric response, increases dielectric losses and lowers molecular mobility at low temperatures. The findings showed that aging significantly alters the dielectric response, increases dielectric losses, and reduces molecular mobility specifically at low temperatures. The Cole-Cole model was employed to assess the dielectric relaxation model, but its accuracy was compromised at extremely low temperatures. The effect of low temperatures on transformer oil viscosity and DC conductivity also considered. Which shows the viscosity increases exponentially as the temperature decreased, leading to reduced conductivity. The temperature dependence of viscosity and conductivity was well described by the Arrhenius and Vogel Fulcher Tammann models. These findings highlight the critical need to assess the aging and temperature effects on insulating materials to ensure the reliability of power equipment under harsh operating conditions. Physical sciences/Engineering Physical sciences/Engineering/Electrical and electronic engineering Oil immersed power Equipment Viscosity analysis Transformer Oil OIP Frequency Domain spectroscopy Vogel Fulcher Tammann Model low temperature Cole-Cole model Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 24 Nov, 2025 Reviews received at journal 23 Nov, 2025 Reviews received at journal 21 Nov, 2025 Reviewers agreed at journal 21 Nov, 2025 Reviewers agreed at journal 06 Nov, 2025 Reviewers agreed at journal 23 Aug, 2025 Reviewers agreed at journal 04 Jul, 2025 Reviewers agreed at journal 07 Jun, 2025 Reviews received at journal 28 May, 2025 Reviewers agreed at journal 22 May, 2025 Reviewers invited by journal 22 May, 2025 Editor assigned by journal 22 May, 2025 Editor invited by journal 21 May, 2025 Submission checks completed at journal 21 May, 2025 First submitted to journal 07 May, 2025 You are reading this latest preprint version Research Square lets you share your work early, gain feedback from the community, and start making changes to your manuscript prior to peer review in a journal. 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Also discoverable on Platform About Our Team In Review Editorial Policies Advisory Board Help Center Resources Author Services Accessibility API Access RSS feed Manage Cookie Preferences © Research Square 2026 | ISSN 2693-5015 (online) Privacy Policy Terms of Service Do Not Sell My Personal Information {"props":{"pageProps":{"initialData":{"identity":"rs-6616199","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":461464729,"identity":"c3e19a5e-d1f4-4ece-8196-ca2a7d76c8e3","order_by":0,"name":"Raheel Ahmed","email":"data:image/png;base64,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","orcid":"","institution":"Harbin University of Science and Technology","correspondingAuthor":true,"prefix":"","firstName":"Raheel","middleName":"","lastName":"Ahmed","suffix":""},{"id":461464730,"identity":"4b683d95-d455-4c36-93ac-43455b7b7c52","order_by":1,"name":"Ji Liu","email":"","orcid":"","institution":"Harbin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Ji","middleName":"","lastName":"Liu","suffix":""},{"id":461464731,"identity":"5127172c-e9bf-4f18-8430-5235dd0ac2ca","order_by":2,"name":"Mingze Zhang","email":"","orcid":"","institution":"Harbin University of Science and Technology","correspondingAuthor":false,"prefix":"","firstName":"Mingze","middleName":"","lastName":"Zhang","suffix":""},{"id":461464732,"identity":"c9a7bca2-61d5-4a61-b468-b40134a2d5f7","order_by":3,"name":"Xianhao Fan","email":"","orcid":"","institution":"Tsinghua University","correspondingAuthor":false,"prefix":"","firstName":"Xianhao","middleName":"","lastName":"Fan","suffix":""}],"badges":[],"createdAt":"2025-05-08 03:23:18","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-6616199/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6616199/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":83441069,"identity":"77510ae3-78ab-4172-93f9-f8f9eacbfa24","added_by":"auto","created_at":"2025-05-26 09:37:12","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":1339730,"visible":true,"origin":"","legend":"","description":"","filename":"manuscriptforSR.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6616199/v1_covered_6c69708e-9edd-427c-b44e-9b70f9dccb9a.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Evaluation of Insulation Performance in Oil-Immersed Power Equipment Under Low Temperatures","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":true,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"scientific-reports","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":false,"externalIdentity":"scirep","sideBox":"Learn more about [Scientific Reports](http://www.nature.com/srep/)","snPcode":"","submissionUrl":"","title":"Scientific Reports","twitterHandle":"","acdcEnabled":true,"dfaEnabled":true,"editorialSystem":"stoa","reportingPortfolio":"Scientific Reports","inReviewEnabled":true,"inReviewRevisionsEnabled":true},"keywords":"Oil immersed power Equipment, Viscosity analysis, Transformer Oil, OIP, Frequency Domain spectroscopy, Vogel Fulcher Tammann Model, low temperature, Cole-Cole model","lastPublishedDoi":"10.21203/rs.3.rs-6616199/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6616199/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eTo investigate the dielectric properties of oil-impregnated paper and transformer oil at low temperature conditions that effect the performance of power equipment situated at cold climatic zone. 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