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<div>In this research, the use of a Type-2 superconducting material (i.e. Yttrium Barium Copper Oxide) as a magnetic flux source within synchronous machines is considered. To do so, an analytical model is applied to predict the magnetic field and the currents that are induced within the material when it is magnetized to a mixed-state. These induced currents are then used to model the synchronous machine performance within a 2-dimensional Method of Moments (MoM) formulation. The MoM-based model is used in tandem with a thermal equivalent circuit to calculate the cooling required to keep the YBCO below its critical temperature. These are utilized within a genetic algorithm (GA) to evaluate the tradeoffs between mass and loss for several example electric drives ranging from 10 kW-20 MW. The expected mass and loss of the YBCO machines are compared to those of a standard permanent magnet synchronous machine (PMSM). Specifically, Pareto-optimal fronts are used to assess power levels where cryo-cooled YBCO materials may be warranted.<br></div>

In reference to IEEE copyrighted material which is used with permission in this thesis, the IEEE does not endorse any of McMaster University's products or services. Internal or personal use of this material is permitted. If interested in reprinting/republishing IEEE copyrighted material for advertising or promotional purposes or for creating new collective works for resale or redistribution, please go to http://www.ieee.org/publications_standards/publications/rights/rights_link.html to learn how to obtain a License from RightsLink. / The need for reductions in global greenhouse gas emissions, coupled with rising fuel prices, has motivated intense research in the area of hybrid and fully electric crafts for commercial applications in the aviation sector. This thesis explores implementation of Halbach arrays in high-speed radial flux machines (RFMs) and low-speed axial flux machines (AFMs) for aerospace applications. Highly accurate analytical equations are developed for quickly predicting the magnetic field in the latter (both for coreless and steel core stators) due to the complex three dimensional axial flux paths which make traditional finite element analysis time-consuming. Electromagnetic design and optimization of two aerospace machines that use Halbachs are detailed. The first is a ~14 kW AFM intended to replace an existing high lift motor RFM concept in NASA’s Maxwell X57 all-electric plane. Two design variants are selected which achieve a 10 % increase in torque/power and a 10 % decrease in mass/volume, respectively. The second machine is a 20,000 RPM surface permanent magnet RFM capable of 150 kW peak power output that is intended as a proof-of-concept for the later development of a megawatt machine for a hybrid and/or all-electric aircraft. / Thesis / Master of Applied Science (MASc)

With the unstable cost and supply of rare earth materials used in permanent magnet electric machines, many alternative machine types are being studied which are suitable for different applications. The focus of this thesis is the design of a novel 6/14 switched reluctance machine which can be fitted in a residential heating, ventilation, and air-conditioning (HVAC) application based on measured performance characteristics of an existing surface mount permanent-magnet synchronous (SMPS) machine. Residential electric motor applications are reviewed and in particular - furnace blower motor appliances. The fundamentals of switched reluctance machines are discussed, including the mechanism, operation, and control strategy. A SMPS motor which is commercially available for retrofitting into residential HVAC systems is analyzed to find its performance characteristics through disassembly, inspection, and dynamometer bench testing. The design of a novel 6/14 SRM optimization process is outlined to investigate the effect of changing the geometry values within the motor on the performance characteristics, while keeping within the size constraints of the original motor. A novel 6/14 SRM design is presented which is capable of achieving the target goals in the desired operating conditions. Further suitability testing is performed in terms of thermal analysis of the motor in the peak and continuous operating condition and mechanical stress analysis of the rotor under various rotational speeds. The full CAD assembly of the motor is designed including components from the original SMPS motor to allow for fitting in the same HVAC application. / Thesis / Master of Applied Science (MASc) / With the unstable cost and supply of rare earth materials used in permanent magnet electric motors, many alternative machine types are being studied which are suitable for different applications. The focus of this thesis is the design of a novel 6/14 switched reluctance machine which can be fitted in a residential heating, ventilation, and air-conditioning (HVAC) application based on measured performance characteristics of an existing surface mount permanent-magnet synchronous (SMPS) machine. Switched reluctance machines have a number of benefits over permanent magnet machines including that they do not have permanent magnets, are less sensitive to high heat scenarios, have lower manufacturing costs, are more robust, and are generally capable of higher operating speeds. Residential electric motor applications are reviewed and in particular - furnace blower motor appliances. The fundamentals of switched reluctance machines are discussed, including the mechanism, operation, and control strategy. A SMPS motor which is commercially available for retrofitting into residential furnace systems is analyzed to find its performance characteristics through disassembly, inspection, and dynamometer bench testing. The design of a novel 6/14 SRM optimization process is outlined to investigate the effect of changing the geometry values within the motor on the performance characteristics, while keeping within the size constraints of the original motor. A novel 6/14 SRM design is presented which is capable of achieving the target goals in the desired operating conditions. Further suitability testing is performed in terms of thermal analysis of the motor in the peak and continuous operating condition and mechanical stress analysis of the rotor under various rotational speeds. The full 3D CAD assembly model of the motor is designed including components from the original SMPS motor to allow for fitting in the same HVAC application.

<p dir="ltr">Recent regulatory changes have been proposed to phase down the use of hydrofluorocarbon</p><p dir="ltr">(HFC)-based refrigerants in air conditioning and refrigeration systems. The proposed</p><p dir="ltr">low global warming potential alternatives (low-GWP) are characterized by lower volumetric</p><p dir="ltr">capacities, which require either higher displacements or higher speeds to meet compressor</p><p dir="ltr">loads. In order to address this, the coupled optimization of a compressor system and its electric</p><p dir="ltr">drive has been proposed. The primary goal of this thesis is to establish tools that can be</p><p dir="ltr">used to assess the impact that alternative low-GWP refrigerants have on the sizing and performance</p><p dir="ltr">of electrically driven compressors. Toward this goal, a method-of-moments-based</p><p dir="ltr">model has been established and structured to enable rapid evaluation of the electromagnetic</p><p dir="ltr">performance of V-shaped interior magnet machines. Contributions to the model formulation</p><p dir="ltr">include the use of a judicious combination of point and pulse basis functions to evaluate</p><p dir="ltr">machine behavior under saturation of stator and rotor steels. Also included is a straightforward</p><p dir="ltr">means to include multiple operating points with minimal additional computational</p><p dir="ltr">expense. Coupled to the electromagnetic model is a thermal equivalent circuit model that</p><p dir="ltr">includes conductive heat transfer between slot winding bundles and stator steel. It also includes</p><p dir="ltr">convective heat transfer from the stator to the rotor through the airgap. The proposed</p><p dir="ltr">models have been validated using commercial finite-element based software. Subsequently,</p><p dir="ltr">they have been applied in design optimization studies used to compare the efficiency and size</p><p dir="ltr">(mass) between machines designed for a common HFC refrigerant (R410A) and a proposed</p><p dir="ltr">alternative (R454B).</p>

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Traffic congestion in large urban and metropolitan areas is a substantial problem plaguing these areas. Not only are commuters losing valuable time, but greenhouse gas emissions are substantially worse because of congestion. Considerable research and development into next generation electrified aircraft is ongoing to introduce air mobility as a viable new means of transporting people and goods across long commutes. This development extends into commercial aviation as a whole as a means of reducing the industry’s carbon footprint with new aircraft designs that employ electrified propulsion systems. Many electrified aircraft projects are currently underway, ranging from small commuter aircraft all the way to large twin-aisle aircraft, and part of the development scope for alot of these projects is creating highly robust and power dense electric machines that replace the current state-of-the-art. The axial flux permanent magnet synchronous machine is an exciting candidate for aircraft propulsion due to its exceptional torque density and compact axial nature. In this thesis, the mechanical design for three generations of axial flux permanent magnet synchronous machines is discussed. These machines serve as development phase prototypes for machines that are ultimately intended for propulsion applications in commercial aviation, particularly for eVTOL aircraft. The motivation for electrification in the commercial aviation industry is discussed, followed by an overview of the development landscape for electrified propulsion systems in commercial aviation, focusing primarily on electric machines that are currently state-of-the-art or are set to be in the near future, as well as what is required for future electric machines in terms of power output and power density. The axial flux architecture is then presented, including a high-level comparison to the radial-flux architecture, an overview of the various axial flux machine designs and topologies, and a discussion of the inherent mechanical design challenges associated with the axial flux architecture. The yokeless and segmented armature axial flux permanent magnet synchronous machine design was selected for the machines developed as part of the research for this thesis, and the discussion of the mechanical design of these machines is broken up into the two core sub assemblies: stator assembly and rotating assembly. High-level design methodologies are introduced for both sub-assemblies, which is further broken down into different approaches pertaining to each generation. The first and second generation designs are presented at a high level, followed by deep-dives into the complete mechanical design for the third generation stator, the bearing selection, arrangement, and analysis for the third generation rotating assembly, and adhesive characterization trials used to guide adhesive selection for rotor magnetics retention in the second and third generation machines. The current status of the machines and any outcomes from testing that has been conducted thus far, particularly with respect to performance, is presented at the end. / Thesis / Master of Applied Science (MASc)

O objetivo do trabalho é apresentar o funcionamento de um gerador a relutância chaveado monofásico. Para isso, foi desenvolvido um modelo computacional em ambiente Matlab Simulink, fazendo-se a comunicação entre diferentes partes do sistema. O comportamento da dinâmica de geração é apresentado para diferentes pontos do sistema, e testes experimentais realizados em um pequeno protótipo confirmam as características funcionais desta máquina. Ensaios realizados comprovam sua funcionalidade e simplicidade de operação, tendo estabilidade de geração para ampla faixa de velocidade de funcionamento, caracterizando uma máquina promissora, robusta e eficiente para aplicações especiais. / This work presents a single-phase switched reluctance machine operating as a generator. For that purpose, a computational model was developed in Matlab Simulink environment, wherein all the system components, such as voltage source, drive and machine model, and load were integrated. The current and voltage behavior for several points of operations are presented. Furthermore, experimental tests were also carried out in a simple prototype to validate its functionality and simplicity of operation, providing a stable power generation over a wide range of speed. The results showed that the single-phase switched reluctance generator can be robust, efficient, and promising for especial applications.

O objetivo do trabalho é apresentar o funcionamento de um gerador a relutância chaveado monofásico. Para isso, foi desenvolvido um modelo computacional em ambiente Matlab Simulink, fazendo-se a comunicação entre diferentes partes do sistema. O comportamento da dinâmica de geração é apresentado para diferentes pontos do sistema, e testes experimentais realizados em um pequeno protótipo confirmam as características funcionais desta máquina. Ensaios realizados comprovam sua funcionalidade e simplicidade de operação, tendo estabilidade de geração para ampla faixa de velocidade de funcionamento, caracterizando uma máquina promissora, robusta e eficiente para aplicações especiais. / This work presents a single-phase switched reluctance machine operating as a generator. For that purpose, a computational model was developed in Matlab Simulink environment, wherein all the system components, such as voltage source, drive and machine model, and load were integrated. The current and voltage behavior for several points of operations are presented. Furthermore, experimental tests were also carried out in a simple prototype to validate its functionality and simplicity of operation, providing a stable power generation over a wide range of speed. The results showed that the single-phase switched reluctance generator can be robust, efficient, and promising for especial applications.

No description available.