Stability Analysis of a Modified Cascade Control Strategy for Khartoum Refinery Delayed Coking Unit's Drums

Stability Analysis of a Modified Cascade Control Strategy for Khartoum Refinery Delayed Coking Unit's Drums | 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 Research Article Stability Analysis of a Modified Cascade Control Strategy for Khartoum Refinery Delayed Coking Unit's Drums Lina Amer Alsharif Ahmed, Tomadir Awad Ibrahim This is a preprint; it has not been peer reviewed by a journal. https://doi.org/ 10.21203/rs.3.rs-6996682/v1 This work is licensed under a CC BY 4.0 License Status: Posted Version 1 posted You are reading this latest preprint version Abstract This study explores the stability of a modified cascade control strategy recommended to be applied to the delayed coking unit's drum of the Khartoum refinery. A Proportional (P) controller in the secondary loop is replaced with Proportional-Integral (PI) and Proportional-Integral-Derivative (PID) controllers to assess their effect on maintaining drum pressure through heating fuel flow control. System transfer functions were calculated and simulated in MATLAB using direct substitution, root locus, and Bode plot techniques. Findings revealed instability with PI and PID controllers due to phase margin reduction and amplified high-frequency noise. Recommendations include applying lead/lag compensators and advanced controls like Model Predictive Control (MPC) and State Feedback. Chemical Engineering Cascade Control Stability Analysis Delayed Coking Unit MATLAB Simulation Control Systems PI and PID Controllers Full Text Additional Declarations The authors declare no competing interests. Cite Share Download PDF Status: Posted Version 1 posted 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. We do this by developing innovative software and high quality services for the global research community. Our growing team is made up of researchers and industry professionals working together to solve the most critical problems facing scientific publishing. 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-6996682","acceptedTermsAndConditions":true,"allowDirectSubmit":true,"archivedVersions":[],"articleType":"Research Article","associatedPublications":[],"authors":[{"id":477691064,"identity":"32b46868-4d7e-4bb1-a12f-98ebe14561ef","order_by":0,"name":"Lina Amer Alsharif Ahmed","email":"data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAZAAAAAyAQMAAABI0h/eAAAABlBMVEX///8AAABVwtN+AAAACXBIWXMAAA7EAAAOxAGVKw4bAAABBElEQVRIiWNgGAWjYBAC+wYg8cAASDCDuBUHwKIHHuDRAlLMkAAi2UGazxxg4AFpSSCoBUTwAC1gbINoYcCrRbr9AkNCwR15BonsxMeV8+7I2Ysdfgi0xU5OtwGHX2TOFAAd9sywQSJ3s+HZbc+MeaTTDIBako3NDuCwRSInAajlMCNQyzbJxm2HE3ukE0BaDiRuI6DFvkH+7fafjXNAWtI/ENCSfgCkJRFkC2NjA0hLDkFbQIF8OBnkF8mGY4eNeW7nFBxIMMDtF/sZ6Q8YPvw5bAvUsvFjQ81hOfbZ6Zs/fKiwk8OlBRgf5j/AelEVGOBSDgLsD/DJjoJRMApGwShgYAAAcmtlAv7VoYAAAAAASUVORK5CYII=","orcid":"https://orcid.org/0009-0009-2037-0731","institution":"Sudan University Of Science And Technology","correspondingAuthor":true,"prefix":"","firstName":"Lina","middleName":"Amer Alsharif","lastName":"Ahmed","suffix":""},{"id":477691065,"identity":"f61c8121-7dc6-4631-841a-52986f6c5cbc","order_by":1,"name":"Tomadir Awad Ibrahim","email":"","orcid":"","institution":"Sudan University Of Science And Technology","correspondingAuthor":false,"prefix":"","firstName":"Tomadir","middleName":"Awad","lastName":"Ibrahim","suffix":""}],"badges":[],"createdAt":"2025-06-28 09:05:47","currentVersionCode":1,"declarations":{"humanSubjects":false,"vertebrateSubjects":false,"conflictsOfInterestStatement":false,"humanSubjectEthicalGuidelines":false,"humanSubjectConsent":false,"humanSubjectClinicalTrial":false,"humanSubjectCaseReport":false,"vertebrateSubjectEthicalGuidelines":false},"doi":"10.21203/rs.3.rs-6996682/v1","doiUrl":"https://doi.org/10.21203/rs.3.rs-6996682/v1","draftVersion":[],"editorialEvents":[],"editorialNote":"","failedWorkflow":false,"files":[{"id":85817730,"identity":"e6d2c678-117e-4720-a6ef-768745d34390","added_by":"auto","created_at":"2025-07-02 06:04:02","extension":"pdf","order_by":1,"title":"","display":"","copyAsset":false,"role":"manuscript-pdf","size":714129,"visible":true,"origin":"","legend":"","description":"","filename":"THESTABILITYANALYSIS.pdf","url":"https://assets-eu.researchsquare.com/files/rs-6996682/v1_covered_250f8ed6-ef1a-4f36-aaab-b7ff61541f8d.pdf"}],"financialInterests":"The authors declare no competing interests.","formattedTitle":"\u003cp\u003eStability Analysis of a Modified Cascade Control Strategy for Khartoum Refinery Delayed Coking Unit's Drums \u003c/p\u003e","fulltext":[],"fulltextSource":"","fullText":"","funders":[],"hasAdminPriorityOnWorkflow":false,"hasManuscriptDocX":false,"hasOptedInToPreprint":true,"hasPassedJournalQc":"","hasAnyPriority":true,"hideJournal":true,"highlight":"","institution":"Sudan University of Science and Technology","isAcceptedByJournal":false,"isAuthorSuppliedPdf":true,"isDeskRejected":"","isHiddenFromSearch":false,"isInQc":false,"isInWorkflow":false,"isPdf":true,"isPdfUpToDate":true,"isWithdrawnOrRetracted":false,"journal":{"display":true,"email":"[email protected]","identity":"researchsquare","isNatureJournal":false,"hasQc":true,"allowDirectSubmit":true,"externalIdentity":"","sideBox":"","snPcode":"","submissionUrl":"/submission","title":"Research Square","twitterHandle":"researchsquare","acdcEnabled":true,"dfaEnabled":false,"editorialSystem":"","reportingPortfolio":"","inReviewEnabled":false,"inReviewRevisionsEnabled":true},"keywords":" Cascade Control, Stability Analysis, Delayed Coking Unit, MATLAB Simulation, Control Systems, PI and PID Controllers","lastPublishedDoi":"10.21203/rs.3.rs-6996682/v1","lastPublishedDoiUrl":"https://doi.org/10.21203/rs.3.rs-6996682/v1","license":{"name":"CC BY 4.0","url":"https://creativecommons.org/licenses/by/4.0/"},"manuscriptAbstract":"\u003cp\u003eThis study explores the stability of a modified cascade control strategy recommended to be applied to the delayed coking unit's drum of the Khartoum refinery. 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