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Design, Analysis, Implementation and Operation of a Brushless Doubly Fed Reluctance Motor Drive

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Design, Analysis, Implementation and Operation of a Brushless Doubly Fed Reluctance Motor Drive University of Calgary PRISM: University of Calgary's Digital Repository Graduate Studies The Vault: Electronic Theses and Dissertations 2018-06-04 Design, Analysis, Implementation and Operation of a Brushless Doubly Fed Reluctance Motor Drive Rebeiro, Ronald Shourav Rebeiro, R. S. (2018). Design, Analysis, Implementation and Operation of a Brushless Doubly Fed Reluctance Motor Drive (Unpublished doctoral thesis). University of Calgary, Calgary, AB. doi:10.11575/PRISM/31965 http://hdl.handle.net/1880/106730 doctoral thesis University of Calgary graduate students retain copyright ownership and moral rights for their thesis. You may use this material in any way that is permitted by the Copyright Act or through licensing that has been assigned to the document. For uses that are not allowable under copyright legislation or licensing, you are required to seek permission. Downloaded from PRISM: https://prism.ucalgary.ca UNIVERSITY OF CALGARY Design, Analysis, Implementation and Operation of a Brushless Doubly Fed Reluctance Motor Drive by Ronald Shourav Rebeiro A THESIS SUBMITTED TO THE FACULTY OF GRADUATE STUDIES IN PARTIAL FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY GRADUATE PROGRAM IN ELECTRICAL AND COMPUTER ENGINEERING CALGARY, ALBERTA JUNE, 2018 © Ronald Shourav Rebeiro 2018 Abstract The permanent magnet synchronous motor (PMSM) is a popular choice for variable speed drive (VSD) applications. However, concerns regarding the low availability and price volatility of rare earth permanent magnet materials are encouraging researchers to reduce or even remove the permanent magnets from electrical machines without significantly compromising their performance. The Brushless Doubly Fed Reluctance Machine (BDFRM) can be a promising prospect with its unique advantageous features over other conventional machines. The BDFRM has two stator windings and a reluctance type rotor. It does not consist of brushes, rotor circuits or magnets. This makes the BDFRM an attractive prospect of a controllable, low cost, low maintenance machine which can be even more robust and versatile than the PMSM. If such a machine is commercially realized, it will be highly suitable to operate in locations of limited accessibility or harsh climate. With proper control technique being utilized, it can be an attractive replacement for two important electrical applications: wind power system and electric vehicle. The concept of Brushless Doubly Fed Machine (BDFM) was first introduced more than a century ago. Much of the published literature has analyzed existing designs, rather than focusing on the design process and effective operation of possible commercial machines. This work describes the complete evaluation of a ducted rotor BDFRM design process through time-stepped finite element analysis (FEA), a prototype machine built based on the design, and two-converters based operation of the BDFRM drive in three different operating modes. In this regard, theoretical aspects and control approach are also discussed and explained. Another objective of this work is to investigate the two-converters based frequency sharing operation (Mode-3) of the prototype BDFRM drive. In this case, the total applied frequency is split between the two stator windings with a specific ratio. Thus, the frequency dependent core loss can be ii reduced. Besides, this approach can provide additional degrees of freedom for control, extend the constant torque region, and increase the machine power density. iii Acknowledgements First and foremost, I’d like to thank the University of Calgary and my supervisor Dr. Andrew M. Knight for guiding me all the way in my research. The completion of this research work would not have been possible without the continuous support, careful supervision, and encouragement from Dr. Knight. I started my research at the University of Alberta before I transferred my program to the University of Calgary. Therefore, the University of Alberta deserves my acknowledgment as well. I thank the Final Exam Committee members and the ECE Department administration personnel for their valuable suggestions and assistance during my exam. I acknowledge the ample support of Tech Support personnel (Garwin Hancock, Rob Thomson, and others) while I was developing the drive facility and running the tests at the machine lab. My special gratitude goes to my parents (Denis Rebeiro & Elizabeth Rebeiro) who were the prime source of my inspiration. Similarly, I acknowledge the inspiration and teaching from all my teachers from my early years who had faith in my abilities (particularly Dr. Mohammad Ali Choudhury, Dr. Md. Abdul Matin, Dr. Nasir Uddin, and Dr. Tapan K. Chakraborty). During the last few years, my wife Jackline played a major role in this journey with her constant support and care. I also acknowledge the moral support from my sisters and their families, my well-wishing elders, relatives, and friends. My classmates and colleagues also made my journey easier by cheering me up and holding thoughtful conversations. Finally, I’d like to thank the Almighty on this occasion for all the good things in my life. iv Table of Contents Abstract ............................................................................................................................... ii Acknowledgements ............................................................................................................ iv Table of Contents .................................................................................................................v List of Tables .................................................................................................................... vii List of Figures and Illustrations ....................................................................................... viii List of Symbols, Abbreviations and Nomenclature .......................................................... xii CHAPTER 1: INTRODUCTION ........................................................................................1 1.1 Introduction ................................................................................................................1 1.2 History of BDFRM ....................................................................................................3 1.3 Research Motivation ..................................................................................................4 1.4 Thesis Contribution ....................................................................................................9 1.5 Thesis Organization .................................................................................................10 CHAPTER 2: THEORY OF BDFRM ...............................................................................12 2.1 Basic Operation Principle of BDFRM .....................................................................12 2.2 Previous Relevant Research on BDFRM.................................................................13 2.3 Operation Principle of a Ducted Rotor BDFRM .....................................................18 2.4 Control Strategy of BDFRM ....................................................................................22 2.5 BDFRM Operation with Appropriate Frequency Division .....................................26 CHAPTER 3: DESIGN OF BDFRM, SIMULATION RESULTS AND DATA ANALYSIS ...................................................................................................................................28 3.1 Choice of Number of Rotor Poles............................................................................28 3.2 Proposed BDFRM Design .......................................................................................30 3.2.1 Evolution of the Proposed Design in JMAG ...................................................35 3.2.2 Windings Configuration of the Proposed Design ............................................40 3.3 Simulation & Data Analysis: Synchronous BDFRM Operation .............................41 3.4 Simulation & Data Analysis: Two-Converters Based Operation ............................46 3.5 Advantages of Two-Converters Based Operation ...................................................51 3.6 Compensation for End Winding Leakage Inductance Effect ..................................53 3.7 Structural Analysis and Final Design for Machine Manufacturing Process ............55 3.8 Calculation of Machine Inductance from Simulation ..............................................58 CHAPTER 4: PROTOTYPE MOTOR AND TEST FACILITY ......................................60 4.1 Stator and Rotor Laminations Design ......................................................................60 4.2 Design of the Rotor Core .........................................................................................64 4.3 Stator Windings Arrangement .................................................................................65 4.4 Assembly of the Machine ........................................................................................68 4.5 Motor Drive Implementation ...................................................................................70 4.6 Control Strategy of Two-Converters Based Operation ............................................73 CHAPTER 5: EXPERIMENTAL TESTING ....................................................................77 5.1 Measurement of Actual Machine Inductances .........................................................77 5.2 Operating Mode-1: Synchronous BDFRM Operation .............................................80
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