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Electromechanics of an Ocean Current Turbine University of New Orleans ScholarWorks@UNO University of New Orleans Theses and Dissertations Dissertations and Theses Fall 12-18-2015 Electromechanics of an Ocean Current Turbine Vasileios Tzelepis University of New Orleans, [email protected] Follow this and additional works at: https://scholarworks.uno.edu/td Part of the Controls and Control Theory Commons, Dynamics and Dynamical Systems Commons, Electrical and Electronics Commons, Electro-Mechanical Systems Commons, Engineering Mechanics Commons, Ocean Engineering Commons, Operations Research, Systems Engineering and Industrial Engineering Commons, and the Power and Energy Commons Recommended Citation Tzelepis, Vasileios, "Electromechanics of an Ocean Current Turbine" (2015). University of New Orleans Theses and Dissertations. 2112. https://scholarworks.uno.edu/td/2112 This Thesis is protected by copyright and/or related rights. It has been brought to you by ScholarWorks@UNO with permission from the rights-holder(s). You are free to use this Thesis in any way that is permitted by the copyright and related rights legislation that applies to your use. For other uses you need to obtain permission from the rights- holder(s) directly, unless additional rights are indicated by a Creative Commons license in the record and/or on the work itself. This Thesis has been accepted for inclusion in University of New Orleans Theses and Dissertations by an authorized administrator of ScholarWorks@UNO. For more information, please contact [email protected]. Electromechanics of an Ocean Current Turbine A Thesis Submitted to the Graduate Faculty of the University of New Orleans in partial fulfillment of the requirement for the degree of Master of Science in Engineering by Vasileios Tzelepis B.Sc. Technological Educational Institute of Athens, 2012 December, 2015 Copyright 2015, VASILEIOS TZELEPIS ii Cambay’s Water Sailing down the river with the anchors down. Our navigator had his forehead painted ''and if you are away I'll be waiting for you for 1000 years'' however the ropes stiffened your palm. Blurry waters and the current for four miles the coolies eat secretly rice with curry our captain looks at the moon which is blurry and red like blood. The tugboat blew three times and continued for forty days you were counting the miles but today you had cobra poison on your lips when you said ''I'm coming out another day'' angrily. At night I told you a story at the forecastle the same one that all sailors narrate at the port your eyes were dominated by Sirocco and you were mumbling all the time ''Wrong way''. We're off! We are waited for in Brazil. Your face must have been wet by cold wind. The bogaz transmits hot breeze but neither a skirt in the shore nor a handkerchief. Nikos Kavvadias To all the people who love the sea…. and to my parents, who allow me to dream…. iii Acknowledgments I would like to exclusively acknowledge my graduate studies mentor and advisor Dr. Nikolaos Xiros for always having the patience, serenity and knowledge to guide me complete this thesis on time and for his unceasing assistance from the first moment I arrived in USA. I would like also to acknowledge Dr. James VanZwieten, research professor at Florida Atlantic University (FAU) and at Southeast National Marine Renewable Energy Center (SNMREC), for helping me with his tremendous knowledge about ocean current technology and also United States National Science Foundation (US NSF) for granting this thesis. On a different note, I should like to particularly mention my wife, Gloria Nathalie Calderon Garcia, who supports me and especially state her compromise with my love for that science. iv Table of Contents List of Figures ................................................................................................................................. ix List of Tables ................................................................................................................................. xx Abstract ......................................................................................................................................... xxi Chapter 1 .......................................................................................................................................... 1 Introduction ................................................................................................................................. 1 1.1 Ocean Current Energy ..................................................................................................... 1 1.1.1 Current phenomena explanation ......................................................................... 1 1.1.2 Resource potential ............................................................................................... 2 1.2 Resource Utilization Technology .................................................................................... 3 1.2.1 Principle of work ................................................................................................. 4 1.2.2 Anchoring/Mooring Systems and Locations ....................................................... 5 1.2.3 Environmental Considerations ............................................................................ 6 1.2.4 Economic Considerations ................................................................................... 6 1.2.5 Challenges ........................................................................................................... 6 1.3 Projects in the World ..................................................................................................... 8 1.3.1 Real Projects and Tidal/Current Turbines ........................................................... 8 1.3.2 Projects in Progress ........................................................................................... 13 1.3.3 Southern National Marine Renewable Energy Center (SNMREC) .................. 19 1.4 Generator and Drive-Train Options ............................................................................ 21 1.5 Thesis Outline ............................................................................................................. 24 Chapter 2 ........................................................................................................................................ 25 Induction Motors/Generators .................................................................................................... 25 2.1 Introduction ................................................................................................................... 25 2.2 Principles of Design and Operation .............................................................................. 25 2.2.1 Basic Construction ............................................................................................ 25 2.2.2 Stator ................................................................................................................. 26 2.2.3 Rotor (Armature) .............................................................................................. 27 2.2.4 Number of Poles and Speed .............................................................................. 29 2.2.5 Operating Principle of Three (3) Phase ............................................................. 31 2.2.5.1 Rotating Magnetic Field ...................................................................... 31 2.2.5.2 Production of Rotating Magnetic Field ............................................... 32 2.2.5.3 Resultant 3-Phase Field ....................................................................... 35 2.2.6 Main (Air-Gap) Flux and Leakage Flux ........................................................... 36 2.2.7 Types of AC Induction Motors ......................................................................... 36 2.2.7.1 Single-Phase ........................................................................................ 36 v 2.2.7.2 Three-Phase ......................................................................................... 36 2.2.7.2.1 Squirrel Cage Rotor ........................................................... 41 2.2.7.2.2 Wound Rotor ...................................................................... 42 2.2.8 Load Characteristics .......................................................................................... 43 2.2.9 Efficiency and Losses ....................................................................................... 45 2.2.10 Typical Nameplate .......................................................................................... 46 2.3 Modeling in MATLAB/Simulink® .............................................................................. 48 2.3.1 Model Description ............................................................................................ 48 2.3.2 Model Assumptions .......................................................................................... 48 2.3.3 Numerical Model .............................................................................................. 49 2.4 Case Studies .................................................................................................................. 53 2.4.1 Case Study I – IG for 20kW OCT ..................................................................... 53 2.4.1.1 Steady State with Zero Load ............................................................... 53 2.4.1.2 Steady State with Load ....................................................................... 54 2.4.1.3 Transient.............................................................................................
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