Emission Spectra and Diagnosis of C4F7N/CO2 Discharge Faults

Emission Spectra and Diagnosis of C4F7N/CO2 Discharge Faults | 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 Emission Spectra and Diagnosis of C4F7N/CO2 Discharge Faults Xianglian Yan, Xiaokun Hua, Wen Wang, Yin Huang, Jian Wang This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-9197201/v1 This work is licensed under a CC BY 4.0 License Status: Under Review Version 1 posted 14 You are reading this latest preprint version Abstract The C 4 F 7 N/CO 2 mixed gas is regarded as one of the most promising environmental-friendly alternatives to SF 6 . Studying its discharge spectral characteristics under different voltages and fault types is of great significance for insulation condition monitoring and fault diagnosis. Based on a 126 kV real-scale GIL experimental platform, this paper conducted DC breakdown, DC surface flashover, and AC surface flashover experiments for 10% C 4 F 7 N/90% CO 2 mixed gas at 0.1 MPa. By constructing a spectral data preprocessing method to eliminate the random interference of discharge, the emission spectral differences between C 4 F 7 N/CO 2 and SF 6 , as well as pure CO 2 gases, were systematically compared, and the spectral evolution laws under different conditions were analyzed. The experimental results show that, unlike the "low, flat, wide" characteristic of the SF 6 spectrum, the C 4 F 7 N/CO 2 mixed gas spectrum presents a "high, thin, steep" form, with energy concentrated in the ultraviolet and near-infrared bands. In the DC breakdown condition, the spectrum is mainly dominated by electrode evaporation (Al resonance line) and gas decomposition (CN, C, O spectral lines); in the DC surface flashover condition, due to the participation of insulator solid materials in discharge decomposition, the CN radical spectral band (385.0 - 387.6 nm) and CII ion spectral lines are significantly enhanced, while the Al and O spectral lines are relatively weakened; in the AC surface flashover condition, the reciprocating motion of charged particles changes the energy transfer mechanism, causing the spectrum to redshift towards the near-infrared region, with the O atomic characteristic peak (777.3 nm) becoming dominant, while the CN characteristic peak is weakened due to the high-frequency thermal accumulation effect. The study reveals the microscopic luminescence mechanism of the C 4 F 7 N/CO 2 mixed gas under the combined action of electrode evaporation, gas ionization, and material decomposition, confirming that changes in specific spectral line intensities can be used as criteria for distinguishing fault types and voltage levels, providing theoretical support for the optical diagnostic technology of environmentally friendly gas-insulated equipment. Physical sciences/Energy science and technology Physical sciences/Materials science Physical sciences/Physics Full Text Additional Declarations No competing interests reported. Cite Share Download PDF Status: Under Review Version 1 posted Editorial decision: Revision requested 27 Apr, 2026 Reviews received at journal 26 Apr, 2026 Reviews received at journal 21 Apr, 2026 Reviewers agreed at journal 16 Apr, 2026 Reviewers agreed at journal 16 Apr, 2026 Reviewers agreed at journal 15 Apr, 2026 Reviewers agreed at journal 13 Apr, 2026 Reviews received at journal 12 Apr, 2026 Reviewers agreed at journal 08 Apr, 2026 Reviewers invited by journal 07 Apr, 2026 Editor assigned by journal 07 Apr, 2026 Editor invited by journal 06 Apr, 2026 Submission checks completed at journal 05 Apr, 2026 First submitted to journal 05 Apr, 2026 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. As a division of Research Square Company, we’re committed to making research communication faster, fairer, and more useful. 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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-9197201","acceptedTermsAndConditions":true,"allowDirectSubmit":false,"archivedVersions":[],"articleType":"Article","associatedPublications":[],"authors":[{"id":621724106,"identity":"c14fb2ed-9929-4504-83b8-b339fb19aeb5","order_by":0,"name":"Xianglian Yan","email":"","orcid":"","institution":"China Electric Power Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Xianglian","middleName":"","lastName":"Yan","suffix":""},{"id":621724107,"identity":"e8262557-59bf-4fae-9bd4-3167487595d7","order_by":1,"name":"Xiaokun Hua","email":"","orcid":"","institution":"North China Electric Power University State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources","correspondingAuthor":false,"prefix":"","firstName":"Xiaokun","middleName":"","lastName":"Hua","suffix":""},{"id":621724108,"identity":"a208c193-e8f9-4199-8b2f-4d6056a74318","order_by":2,"name":"Wen Wang","email":"","orcid":"","institution":"China Electric Power Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Wen","middleName":"","lastName":"Wang","suffix":""},{"id":621724109,"identity":"aef77652-7a3c-4f30-914e-fa79741b3d7f","order_by":3,"name":"Yin Huang","email":"","orcid":"","institution":"China Electric Power Research Institute","correspondingAuthor":false,"prefix":"","firstName":"Yin","middleName":"","lastName":"Huang","suffix":""},{"id":621724110,"identity":"b8c1e17a-c538-44c2-89b9-7071da888fdf","order_by":4,"name":"Jian Wang","email":"data:image/png;base64,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","orcid":"","institution":"North China Electric Power University State Key Laboratory of Alternate Electrical Power System with Renewable Energy Sources","correspondingAuthor":true,"prefix":"","firstName":"Jian","middleName":"","lastName":"Wang","suffix":""}],"badges":[],"createdAt":"2026-03-23 07:54:52","currentVersionCode":1,"declarations":"","doi":"10.21203/rs.3.rs-9197201/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-9197201/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":107480423,"identity":"85345569-8d4e-49b1-9c02-4c43d4c0580c","added_by":"auto","created_at":"2026-04-22 02:10:15","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":578696,"visible":true,"origin":"","legend":"","description":"","filename":"EmissionSpectraandDiagnosisofC4F7NCO2DischargeFaults1.pdf","url":"https://assets-eu.researchsquare.com/files/rs-9197201/v1_covered_7874949a-df69-4c13-a276-6f9db1d72fbb.pdf"}],"financialInterests":"No competing interests reported.","formattedTitle":"Emission Spectra and Diagnosis of C4F7N/CO2 Discharge Faults","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":false,"hideJournal":false,"highlight":"","institution":"","isAcceptedByJournal":false,"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":"","lastPublishedDoi":"10.21203/rs.3.rs-9197201/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-9197201/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThe C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eN/CO\u003csub\u003e2\u003c/sub\u003e mixed gas is regarded as one of the most promising environmental-friendly alternatives to SF\u003csub\u003e6\u003c/sub\u003e. Studying its discharge spectral characteristics under different voltages and fault types is of great significance for insulation condition monitoring and fault diagnosis. Based on a 126 kV real-scale GIL experimental platform, this paper conducted DC breakdown, DC surface flashover, and AC surface flashover experiments for 10% C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eN/90% CO\u003csub\u003e2\u003c/sub\u003e mixed gas at 0.1 MPa. By constructing a spectral data preprocessing method to eliminate the random interference of discharge, the emission spectral differences between C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eN/CO\u003csub\u003e2\u003c/sub\u003e and SF\u003csub\u003e6\u003c/sub\u003e, as well as pure CO\u003csub\u003e2\u003c/sub\u003e gases, were systematically compared, and the spectral evolution laws under different conditions were analyzed. The experimental results show that, unlike the \"low, flat, wide\" characteristic of the SF\u003csub\u003e6\u003c/sub\u003e spectrum, the C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eN/CO\u003csub\u003e2\u003c/sub\u003e mixed gas spectrum presents a \"high, thin, steep\" form, with energy concentrated in the ultraviolet and near-infrared bands. In the DC breakdown condition, the spectrum is mainly dominated by electrode evaporation (Al resonance line) and gas decomposition (CN, C, O spectral lines); in the DC surface flashover condition, due to the participation of insulator solid materials in discharge decomposition, the CN radical spectral band (385.0 - 387.6 nm) and CII ion spectral lines are significantly enhanced, while the Al and O spectral lines are relatively weakened; in the AC surface flashover condition, the reciprocating motion of charged particles changes the energy transfer mechanism, causing the spectrum to redshift towards the near-infrared region, with the O atomic characteristic peak (777.3 nm) becoming dominant, while the CN characteristic peak is weakened due to the high-frequency thermal accumulation effect. The study reveals the microscopic luminescence mechanism of the C\u003csub\u003e4\u003c/sub\u003eF\u003csub\u003e7\u003c/sub\u003eN/CO\u003csub\u003e2\u003c/sub\u003e mixed gas under the combined action of electrode evaporation, gas ionization, and material decomposition, confirming that changes in specific spectral line intensities can be used as criteria for distinguishing fault types and voltage levels, providing theoretical support for the optical diagnostic technology of environmentally friendly gas-insulated equipment.\u003c/p\u003e","manuscriptTitle":"Emission Spectra and Diagnosis of C4F7N/CO2 Discharge Faults","msid":"","msnumber":"","nonDraftVersions":[{"code":1,"date":"2026-04-13 07:22:54","doi":"10.21203/rs.3.rs-9197201/v1","editorialEvents":[{"type":"communityComments","content":0},{"type":"decision","content":"Revision requested","date":"2026-04-27T08:48:53+00:00","index":"","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-26T16:21:47+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-21T14:13:06+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"95552570756812058739575447836287807537","date":"2026-04-16T14:06:40+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"325587895323028749489021273765061121166","date":"2026-04-16T12:24:42+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"57208294056617595404176560947667394391","date":"2026-04-15T04:59:12+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"296850471647102136872358238025264205760","date":"2026-04-13T10:52:55+00:00","index":"hide","fulltext":""},{"type":"editorInvitedReview","content":"","date":"2026-04-12T15:05:51+00:00","index":"hide","fulltext":""},{"type":"reviewerAgreed","content":"123171362639857268689465576882848150980","date":"2026-04-08T13:55:37+00:00","index":"hide","fulltext":""},{"type":"reviewersInvited","content":"","date":"2026-04-07T09:11:40+00:00","index":"","fulltext":""},{"type":"editorAssigned","content":"","date":"2026-04-07T09:02:32+00:00","index":"","fulltext":""},{"type":"editorInvited","content":"","date":"2026-04-07T03:20:27+00:00","index":"","fulltext":""},{"type":"checksComplete","content":"","date":"2026-04-05T08:24:08+00:00","index":"","fulltext":""},{"type":"submitted","content":"Scientific Reports","date":"2026-04-05T08:18:48+00:00","index":"","fulltext":""}],"status":"published","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}}],"origin":"","ownerIdentity":"2f19bb1c-34a5-4aaf-8d23-bdb60544a09e","owner":[],"postedDate":"April 13th, 2026","published":true,"recentEditorialEvents":[],"rejectedJournal":[],"revision":"","amendment":"","status":"under-review","subjectAreas":[{"id":66160233,"name":"Physical sciences/Energy science and technology"},{"id":66160234,"name":"Physical sciences/Materials science"},{"id":66160235,"name":"Physical sciences/Physics"}],"tags":[],"updatedAt":"2026-05-14T04:53:59+00:00","versionOfRecord":[],"versionCreatedAt":"2026-04-13 07:22:54","video":"","vorDoi":"","vorDoiUrl":"","workflowStages":[]},"version":"v1","identity":"rs-9197201","journalConfig":"researchsquare"},"__N_SSP":true},"page":"/article/[identity]/[[...version]]","query":{"redirect":"/article/rs-9197201","identity":"rs-9197201","version":["v1"]},"buildId":"XKTyCvWXoU3ODBz1xrDgd","isFallback":false,"isExperimentalCompile":false,"dynamicIds":[84888],"gssp":true,"scriptLoader":[]}