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Fuzzy Logic Control for Stand-Alone Photovoltaic Energy Conversion

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Fuzzy Logic Control for Stand-Alone Photovoltaic Energy Conversion Fuzzy Logic Control for Stand-alone Photovoltaic Energy Conversion System, and Innovation in Renewable Energy By Zainab Almukhtar A Thesis Submitted to Saint Mary’s University, Halifax, Nova Scotia in Partial Fulfillment of the Requirements for the Degree of Master of Technology Entrepreneurship and Innovation June 29, 2016, Halifax, Nova Scotia Copyright Zainab Almukhtar, 2016 Approved: Dr. Adel Merabet Supervisor Division of Engineering Approved: Dr. Claudia De Fuentes Supervisory Committee Member Management Department, Sobey School of Business Approved: Dr. Rasheed Beguenane External Examiner ECE, Royal Military College Date: June 29th, 2016 Fuzzy Logic Control for Stand-alone Photovoltaic Energy Conversion System, and Innovation in Renewable Energy. by Zainab Almukhtar Abstract In this dissertation, simulation and hardware emulation was implemented to experiment the operation of a power regulation system for stand-alone PV system with DC loads using Fuzzy Logic Control (FLC). The system encompasses the functions of Maximum Power Point Tracking (MPPT) to bring the power to the maximum value, load power regulation and control of battery operation. An algorithm that tracks the maximum power, and the corresponding fuzzy logic controller were developed. An improved method for the battery operation regulation including a fuzzy logic controller was applied. Load voltage regulation was achieved by a modified cascaded PI controller. The power regulation system managed to stabilize the load power, proved fast MPPT tracking and regulation of the battery operation in the presence of fluctuations and fast input variations. The work included a study of the importance of university-industry collaboration to innovation in renewable energy. The current collaboration channels and the contribution of the current work was analysed through a questionnaire directed to the supervisor. June 29th, 2016 Acknowledgement I would like to start by thanking my parents and brother. Without them, I wouldn’t have been able to achieve many of my goals. Many thanks to my husband and my wonderful daughter and son for their encouragement and patience throughout the research work. I would like to express my appreciation to my supervisor Dr. Adel Merabet for his continuous directions, useful comments, and guidance in all the stages of this thesis. Many thanks to Dr. Claudia De Fuentes for the very beneficial directions and for taking the time to read the work and give me very useful feedback. I sincerely thank Saint Mary’s University and the Master of Technology Entrepreneurship and Innovation department for their support. Special thanks to the Faculty of Graduate Studies and Research for their help and readiness to answer my questions and inquiries. Last but not least I thank all the people and friends that helped, and supported me during this work. June 29th, 2016 Table of Contents Chapter 1 ........................................................................................................................... 1 1 Introduction ............................................................................................................... 1 1.1 Problem Definition ............................................................................................... 6 1.2 Objective .............................................................................................................. 7 Chapter 2 ........................................................................................................................... 8 2 Stand- alone PV systems with Battery Storage ...................................................... 8 2.1 Introduction ............................................................................................................... 8 2.2 PV Module ................................................................................................................ 8 2.2.1 PV systems ......................................................................................................... 8 2.2.2 PV Modelling ................................................................................................... 11 2.3 Energy Storage System ........................................................................................... 17 2.3.1 MPPT Techniques ............................................................................................ 17 2.3.2 DC-DC Converters ........................................................................................... 26 2.3.3 Storage Devices ................................................................................................ 28 2.3.4 Power Regulation System ................................................................................ 30 2.4 Applications ............................................................................................................ 33 2.4.1 Solar Cell Technologies ................................................................................... 33 2.4.2 Development of Solar Systems ........................................................................ 35 2.4.3 Obstacles and Potentials in the use of Solar Energy ........................................ 37 2.5 Conclusion ............................................................................................................... 42 Chapter 3 ......................................................................................................................... 44 3 Fuzzy Control System ............................................................................................. 44 3.1 Introduction ............................................................................................................. 44 3.2 Fuzzy Control Theory ............................................................................................. 45 3.2.1 Fuzzy Logic ...................................................................................................... 45 3.2.2 The Structure of the Fuzzy Controller .............................................................. 53 3.2.3 Applications of Fuzzy Control Systems ........................................................... 55 3.3 MPPT Control (Based on FLC) .............................................................................. 58 3.4 Battery Regulator (Based on FLC).......................................................................... 66 3.5 Load Side Control .............................................................................................. 73 3.6 Conclusion ............................................................................................................... 75 Chapter 4 ......................................................................................................................... 76 4 Experimentation and Results ................................................................................. 76 4.1 Introduction ............................................................................................................. 76 4.2 Real Time Control Hardware .................................................................................. 76 4.3 Real Control Software (RT-Lab)............................................................................. 80 4.4 Experimental PV System with Battery Storage. ................................................ 82 4.5 Experimental Results............................................................................................... 85 4.6 Conclusion ............................................................................................................... 98 Chapter 5 ......................................................................................................................... 99 5 Innovation and Technology Transfer .................................................................... 99 5.1 Introduction ............................................................................................................. 99 5. 2 The Classical Understanding of Research ............................................................ 100 5.3 The New Understanding of Basic and Applied Research ..................................... 102 5.4 University-Industry Interaction ............................................................................. 105 5.5 Potential in University-Industry Collaboration. .................................................... 110 5.6 Conclusion ............................................................................................................. 115 Chapter 6 ....................................................................................................................... 116 6 Conclusion .................................................................................................................. 116 6.1 Suggestions for Future Work ................................................................................ 118 References ...................................................................................................................... 120 Appendix A .................................................................................................................... 139 Acronyms and Abbreviations ...................................................................................... 139 Appendix B .................................................................................................................... 141 Specifications of the Hardware Parts .......................................................................... 141 List of Figures
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