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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Machine synchrone à réluctance : modèles équivalents à réseau de réluctances pour la simulation et l’optimisation / Synchronous Reluctance Machine : magnetic equivalent circuits for simulation and optimization

Mariani, Guilherme Bueno 29 March 2016 (has links)
L’enjeu de la thèse concerne la modélisation électromagnétique des machines synchrones à réluctance, avec comme objectif final : obtenir un modèle suffisamment précis et rapide pour, d’une part, être capable de calculer les ondulations de couple et d’autre part servir pour de l’optimisation dimensionnelle et pouvoir être couplé à un logiciel de type circuit pour tester une loi de commande. Un modèle du type schéma réluctant a été mis en place petit à petit avec validations à chaque étape. La modélisation des échanges dans l’entrefer utilise en final une fonction originale (intégrale de Fermi-Dirac) qui a entièrement été paramétrée avec les dimensions caractéristiques de la machine.Ce modèle de la machine, piloté par les courant, a ensuite été couplé avec un circuit électrique grâce à une interface de transformation tension-courant. Les optimisations réalisées avec ce modèle ont permis de mettre en évidence certains manques dans les contraintes dimensionnelles initiales et, celles-ci corrigées, de montrer que ce modèle était parfaitement utilisable pour cette démarche d’optimisation. / This thesis aims the electromagnetic modeling of synchronous reluctance machines, with a final goal: to obtain a fast and sufficiently accurate model, able to calculate the torque ripple and to be used for optimal machine design and also capable to be coupled to circuit software to test control techniques.A MEC (magnetic equivalent circuit) model was created step-by-step and validated at each step. Final model of the air-gap is based on a function (Fermi-Dirac integral), which has been completely parameterized by machine dimensions. This model of the machine is driven by current; afterwards it was coupled with an electric circuit thanks to a voltage-current transformation interface. The optimizations made with the model allowed to highlight some deficiencies in the initial dimensional constraints. After corrections the model could be efficiently used in an optimization process.
12

Reliability Based Multi-Objective Design Optimization for Switched Reluctance Machines

Vadamodala, Lavanya 19 May 2021 (has links)
No description available.
13

Návrh rotoru synchronního reluktančního stroje spouštěného ze sítě pro průmyslové aplikace / Rotor design of a Line-Start Synchronous Reluctance Machine for Industrial Applications

Žíla, Jakub January 2019 (has links)
This diploma thesis deals with design of rotor of synchronous reluctance machines. There is a theoretical description of rotor geometry of synchronous reluctance machine that respects natural flow of magnetic flux inside complete rotor. The parametric model of rotor is made with usage of ANSYS Maxwell and Matlab software. Furthermore, the parameters of the machines are confirmed using the same program. Finally, changes of motor parameters are observed in connection with different rotor geometries.
14

SIMULTANEOUS TORQUE RIPPLE AND ACOUSTIC NOISE MITIGATION IN SWITCH RELUCTANCE MACHINES

Gundogmus, Omer 23 June 2020 (has links)
No description available.
15

Model Predictive Control of Switched Reluctance Machine Drives

Valencia Garcia, Diego Fernando January 2020 (has links)
Model predictive control (MPC) for switched reluctance machine (SRM) drives is studied in this thesis. The objective is to highlight the benefits of implementing MPC to overcome the main drawbacks of SRMs and position them as an attractive alternative among electrical drives. A comprehensive literature review of MPC for SRM is presented, detailing its current trends as an application still at an early stage. The different features of MPC are highlighted and paired with the most challenging and promising control objectives of SRMs. A vision of future research trends and applications of MPC-driven SRMs is proposed, thus drawing a road-map of future projects, barriers to overcome and potential developments. Several important applications can take advantage of the improved features that SRM can get with MPC, especially from the possibility of defining a unified control technique with the flexibility to adapt to different system requirements. The most important cluster for SRM drives is the high- and ultrahigh-speed operative regions where conventional machines cannot work efficiently. SRMs with MPC can complement then the existing demand for electrical drives with high performance under challenging conditions. Three techniques based on the finite control set model predictive control (FCS-MPC) approach are developed out of the proposed road-map. The first one defines a virtual-flux current tracking technique that improves the existing ones in operating at different speeds and more than one quadrant operation. The method is validated for low- and high- power SRMs in simulations and diverse types of current waveform, making it easy to adapt to existing current shaping techniques. It is also validated experimentally for different operating conditions and robustness against parameter variation. The second technique proposed a predictive torque control that bases its model on static-maps, thus avoiding complex analytical expressions. It improves its estimation through a Kalman filter. The third technique uses a virtual-flux predictive torque control, similar to the first technique for current tracking. The techniques are validated at a wide speed range, thus evidencing superiority in performance without modification on the control structure. / Thesis / Doctor of Philosophy (PhD)
16

Evaluation of a Novel Axial Flux Variable Reluctance Machine

Hines, Derek Braden 01 June 2012 (has links) (PDF)
The objective of this thesis is to determine the feasibility of a novel axial flux variable reluctance machine design. The design aims to compete with prevalent rare-earth permanent magnet machines while also implementing an innovative torque ripple minimization strategy. Given the fundamental operating principles, a selection of dimensions, materials, and excitations are prepared for the machine. Special attention is given to the rotor profile which is crucial to operation. Finite element analysis software is used to evaluate a three-dimensional model in terms of inductance and torque. The ultimate potential of the machine is discussed and recommendations for improvement are proposed.
17

ADVANCED THERMAL MANAGEMENT FOR A SWITCHED RELUCTANCE MACHINE / THERMAL MANAGEMENT FOR A SWITCHED RELUCTANCE MACHINE

Marlow, Richard January 2016 (has links)
The thermal management of electric machines is investigated with the application of techniques to a Switched Reluctance Machine and a high-speed Switched Reluctance Machine. Two novel concepts for said management of a Switched Reluctance Machine are proposed and developed: Inter-Laminate Cooling and a Continuous Toroidal Winding. The Inter-Laminate Cooling concept is developed with application to an iron core inductor which serves as a proxy for the electric machine. The experimental results confirmed the capability of the method, expressed by the effectiveness, which defines the performance measure of the applied cooling method; a concept which itself is equally applicable to other cooling methods that may be applied to any electric machine. The effectiveness also describes the gain in allowable input power to the machine which is realized to reach the same thermal limit versus the case without Inter-Laminate Cooling. The Inter-Laminate Cooling was not applied in experimental test to a Switched Reluctance Machine due to the present economic and fabrication limitations. The Continuous Toroidal Winding concept, originally conceived to permit the consideration of a fluid capillary core type of winding to enhance machine cooling, is developed to allow for peripheral cooling of the machine windings and end windings. The Continuous Toroidal Winding version of the Switched Reluctance Machine is investigated for both its thermal and electrical performance in the context of a machine that is equivalent electromagnetically to its conventional counterpart. The Continuous Toroidal Winding Switched Reluctance Machine was found to perform thermally as tested, in a manner superior to that of the conventional machine where the Toroidal machine was simulated and researched at an equivalent level of operation to the conventional machine. The electrical performance of the Toroidal Switched Reluctance Machine although supportive of the simulation analysis used to develop the machine, was not fully conclusive. This may have been due to problematic iron cores used in the construction of the experimental machines. The application of the Inter-Laminate Cooling method to a Switched Reluctance Machine is considered on an analytical basis for the special case of a High Speed Switched Reluctance Machine and found to be of net positive benefit as the machine’s iron losses are dominant over its copper losses. Application of the Inter-Laminate Cooling method to a lower speed machine, whilst beneficial, is not sufficient to significantly impact the temperature of the machine’s windings such that it would offset the loss of specific torque and power. As such, Inter-Laminate Cooling is only applicable where the net benefit is positive overall; in that the gain in input power realized is sufficient to overcome the loss of specific power and torque which will occur due to the increased machine volume. The “effectiveness” and “gain” approach for the evaluation of cooling methods applied to electric machines is a concept which should be adopted to aid in the comparative understanding of the performance of myriad different cooling methods being applied to electric machines both in research and practice, of which there is only minimal understanding. / Thesis / Doctor of Philosophy (PhD)
18

6/14 Switched Reluctance Machine Design for Household HVAC System Applications

Kasprzak, Michael January 2017 (has links)
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.
19

SPLIT WINDING SWITCHED RELUCTANCE MACHINE DRIVES FOR WIDE SPEED RANGE OPERATIONS

Kilic, Oguzhan 14 September 2018 (has links)
No description available.
20

Double-Rotor Switched Reluctance Machine for Integrated Electro-Mechanical Transmission in Hybrid Electric Vehicles

Yang, Yinye 03 March 2015 (has links)
<p>The world transportation sector has been relying on the oil industry for more than a hundred years, accounting for the largest oil consumption and one third of the greenhouse gas emissions. However, with the boosting demand, escalating national energy security concerns and emerging environmental issues, reducing and displacing petroleum fuel in transportation sector has become an urging global target. As a result, hybrid electric vehicles evolve as one solution to displace petroleum fuel by utilizing vehicle onboard electrical systems, achieving higher fuel economy and less emissions by vehicle electrification and hybridization.</p> <p>However, since hybrid electric vehicles add additional electrical components and systems to realize better fuel economy, the system complexity increases and thus the cost increases. Hence, it is an objective of this thesis research to focus on the integrations and optimizations, aiming to simplify and optimize the hybrid power-trains in both system level and component level.</p> <p>This thesis contributes to a novel integrated electro-mechanical hybrid transmission that is potentially more compact and more operational flexible with fewer components compared to the GM Allison Two-Mode hybrid transmission. Comprehensive commercialized power-train transmissions are reviewed and analyzed to serve as background information for comparison. It also contributes to a family of double-rotor switched reluctance machines that are more integrated and suitable for hybrid electric vehicle applications. A prototype double-rotor switched reluctance machine has been built and tested for concept proving. Detailed machine design process is reported with the emphasis on design novelties. Finite element analysis and optimization techniques are applied and the accuracy is confirmed by the experiments. In addition, methods of machine loss analysis, thermal analysis and drive analysis are established; manufacturing and testing procedures are documented in detail that can be used for future machine designs guidance.</p> / Doctor of Philosophy (PhD)

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