{"id":{"repo_id":"uiuc","oai_identifier":"oai:www.ideals.illinois.edu:2142/117783"},"canonical_url":"https://search.dev.ndltd.org/etd/uiuc/oai:www.ideals.illinois.edu:2142/117783","repository":{"repo_id":"uiuc","name":"University of Illinois - Urbana-Champaign","base_url":"https://www.ideals.illinois.edu/oai-pmh"},"display":{"title":"Electro-thermal design and optimization of cryocooled electrical machines","abstract":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-04-12 without embargo terms","abstract_html":"Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-04-12 without embargo terms","abstract_has_math":false,"creators":["Balachandran, Thanatheepan"],"institution":"University of Illinois at Urbana-Champaign","degree_name":"Ph.D.","degree_level":"Dissertation","degree_discipline":"Electrical & Computer Engr","degree_department":null,"school":null,"contributors":["Haran, Kiruba S","Jin, Jianming","Banerjee, Arijit","Stillwell, Andrew"],"advisors":[],"committee_chairs":[],"committee_members":[],"year":2022,"date_issued":"2022-12","date_published":"2022-12","updated_at":"2026-07-22T22:24:56Z","subjects":["Multi-physics Optimization","Cryocooled Electrical Machine","Superconducting Electrical Machine","Ac Loss","Analytical Modeling","Electric Propulsion","Wind Turbine"],"languages":["en","eng"],"rights":["Copyright 2022 Thanatheepan Balachandran"],"rights_urls":[],"identifier_entries":[]},"links":{"outbound_url":"https://hdl.handle.net/2142/117783","outbound_label":"Handle","outbound_source":"dc:identifier"},"metadata_groups":[{"id":"people","label":"People","entries":[{"key":"dc:contributor","label":"Contributor","values":["Haran, Kiruba S","Jin, Jianming","Banerjee, Arijit","Stillwell, Andrew"]},{"key":"dc:creator","label":"Author","values":["Balachandran, Thanatheepan"]}]},{"id":"academic_context","label":"Academic Context","entries":[{"key":"dc:date","label":"Dc Date","values":["2022-12","2022-11-28"]},{"key":"dc:type","label":"Dc Type","values":["text","Thesis"]},{"key":"thesis:degree_discipline","label":"Discipline","values":["Electrical & Computer Engr"]},{"key":"thesis:degree_level","label":"Degree Level","values":["Dissertation"]},{"key":"thesis:degree_name","label":"Degree Name","values":["Ph.D."]},{"key":"thesis:institution_name","label":"Thesis Institution Name","values":["University of Illinois at Urbana-Champaign"]}]},{"id":"subjects_keywords","label":"Subjects and Keywords","entries":[{"key":"dc:subject","label":"Dc Subject","values":["Multi-physics Optimization","Cryocooled Electrical Machine","Superconducting Electrical Machine","Ac Loss","Analytical Modeling","Electric Propulsion","Wind Turbine"]}]},{"id":"language_rights","label":"Language and Rights","entries":[{"key":"dc:language","label":"Dc Language","values":["en","eng"]},{"key":"dc:rights","label":"Dc Rights","values":["Copyright 2022 Thanatheepan Balachandran"]}]},{"id":"identifiers","label":"Identifiers","entries":[{"key":"dc:identifier","label":"Identifier","values":["https://hdl.handle.net/2142/117783"]}]},{"id":"additional","label":"Additional Metadata","entries":[{"key":"dc:description","label":"Description","values":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-04-12 without embargo terms","The student, Thanatheepan Balachandran, accepted the attached license on 2022-11-27 at 22:33.","The student, Thanatheepan Balachandran, submitted this Dissertation for approval on 2022-11-27 at 22:58.","This Dissertation was approved for publication on 2022-11-28 at 14:31.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18638 on 2023-04-12 at 07:33:08","Thermal management is a significant challenge in designing high-power-density electrical machines. Inherent resistivity losses in the electrical system limit conventional machines' achievable power density and efficiency. Cryocooled conductors and superconductors (SC) substantially reduce resistivity losses, enabling higher electrical and magnetic loading of cryocooled electrical machines, and potentially increasing the power density by a factor of ten. However, generated ac losses in these conductors must be removed in bulk, low-efficient cryogenic environments requiring a large amount of cryo-power. This is a substantial hurdle. Therefore, optimizing machine losses and designing efficient cryo-thermal management is necessary for a feasible cryocooled electrical machine. To minimize ac losses and machine weight, an electromagnetic (EM) machine design requires an electro-thermal, multiphysics optimization incorporating conductor properties, a machine thermal model, and a cryogenic cooling scheme. Reliable ac-loss estimation on an armature conductor is a crucial enabler of such an optimization. This dissertation summarizes the efforts of developing a practical electro-thermal analysis and multiphysics optimization for cryocooled electrical machines. Analytical approaches are introduced to capture the spatial and time-harmonics impacts on armature ac losses and verified with finite element analysis (FEA). An ac-loss-measurement test bench is developed to validate the proposed loss-prediction methods and calibrate the motor design analysis. Ac losses in SC samples are experimentally measured and compared against analytical models and FEA results. Examples of multiphysics optimization are presented for electric propulsion motors and wind turbine generators. Sub-scale component hardware tests, including SC armature winding and a rotating cryocooler test bench, are demonstrated for low-frequency applications. Finally, future work focuses on high-frequency tests."]},{"key":"dc:format","label":"Dc Format","values":["application/pdf"]},{"key":"dc:title","label":"Title","values":["Electro-thermal design and optimization of cryocooled electrical machines"]}]}],"canonical_facts":{"dc:contributor":["Haran, Kiruba S","Jin, Jianming","Banerjee, Arijit","Stillwell, Andrew"],"dc:creator":["Balachandran, Thanatheepan"],"dc:date":["2022-12","2022-11-28"],"dc:description":["Submission original under an indefinite embargo labeled 'Open Access'. The submission was exported from vireo on 2023-04-12 without embargo terms","The student, Thanatheepan Balachandran, accepted the attached license on 2022-11-27 at 22:33.","The student, Thanatheepan Balachandran, submitted this Dissertation for approval on 2022-11-27 at 22:58.","This Dissertation was approved for publication on 2022-11-28 at 14:31.","DSpace SAF Submission Ingestion Package generated from Vireo submission #18638 on 2023-04-12 at 07:33:08","Thermal management is a significant challenge in designing high-power-density electrical machines. Inherent resistivity losses in the electrical system limit conventional machines' achievable power density and efficiency. Cryocooled conductors and superconductors (SC) substantially reduce resistivity losses, enabling higher electrical and magnetic loading of cryocooled electrical machines, and potentially increasing the power density by a factor of ten. However, generated ac losses in these conductors must be removed in bulk, low-efficient cryogenic environments requiring a large amount of cryo-power. This is a substantial hurdle. Therefore, optimizing machine losses and designing efficient cryo-thermal management is necessary for a feasible cryocooled electrical machine. To minimize ac losses and machine weight, an electromagnetic (EM) machine design requires an electro-thermal, multiphysics optimization incorporating conductor properties, a machine thermal model, and a cryogenic cooling scheme. Reliable ac-loss estimation on an armature conductor is a crucial enabler of such an optimization. This dissertation summarizes the efforts of developing a practical electro-thermal analysis and multiphysics optimization for cryocooled electrical machines. Analytical approaches are introduced to capture the spatial and time-harmonics impacts on armature ac losses and verified with finite element analysis (FEA). An ac-loss-measurement test bench is developed to validate the proposed loss-prediction methods and calibrate the motor design analysis. Ac losses in SC samples are experimentally measured and compared against analytical models and FEA results. Examples of multiphysics optimization are presented for electric propulsion motors and wind turbine generators. Sub-scale component hardware tests, including SC armature winding and a rotating cryocooler test bench, are demonstrated for low-frequency applications. Finally, future work focuses on high-frequency tests."],"dc:format":["application/pdf"],"dc:identifier":["https://hdl.handle.net/2142/117783"],"dc:language":["en","eng"],"dc:rights":["Copyright 2022 Thanatheepan Balachandran"],"dc:subject":["Multi-physics Optimization","Cryocooled Electrical Machine","Superconducting Electrical Machine","Ac Loss","Analytical Modeling","Electric Propulsion","Wind Turbine"],"dc:title":["Electro-thermal design and optimization of cryocooled electrical machines"],"dc:type":["text","Thesis"],"thesis:degree_discipline":["Electrical & Computer Engr"],"thesis:degree_level":["Dissertation"],"thesis:degree_name":["Ph.D."],"thesis:institution_name":["University of Illinois at Urbana-Champaign"]},"updated_at":"2026-07-22T22:24:56Z"}