Many high performance drive applications require wide Constant Power Speed Range (CPSR) for efficient use of energy. The examples of such applications are the starter alternator system of automobiles proposed for the 42V PowerNet, traction in the hybrid/electric vehicle, wind power generator etc. The Permanent Magnet (PM) machine is the natural choice of such niche applications because of their higher efficiency and compact size. However, the Surface Permanent Magnet (SPM) machine with sine distributed winding and radially-laminated Interior Permanent Magnet (IPM) machine with conventional structure has very limited or zero flux-weakening capability. The flux-weakening capability of the SPM machine can be improved by using concentrated, fractional-slot stator but here well-known advantages of the sine distributed winding are needed to be compromised. In the IPM machine, fluxweakening was improved using axial lamination and more than two magnet layers per pole. However, the construction of such IPM machine is complicated and expensive. This thesis presents design and analysis of a new type of the Interior Permanent Magnet (IPM) machine that have a very wide Constant Power Speed Range (CPSR) without compromising simplicity of construction and advantages of the distribution winding. In the new IPM machine, the magnet poles were segmented in the radially direction and the iron bridges between magnet segments provide for additional paths of flux-canalization to give the rotor an inherent capability of fluxweakening. Consequently, a very wide constant power speed range can be achieved in such machines. The proposed IPM machine of this work was referred as the Segmented IPM machine. The thesis focuses on the optimization of the Segmented IPM machine in a 42V environment of the automobile. First, for the conceptual evaluation a 4 pole, 550W Segmented Magnet IPM machine was optimized using finite element analysis. The parameters were calculated for prediction of the steady-state and transient performances. The torque- and power-speed capability were estimated using time-step, circuit-coupled finite element analysis. The cogging torque and variation of iron loss with frequency were also investigated during the design process. A prototype machine was constructed on the basis of the optimized design. The steady-state and transient performances of the prototype machine were measured and compared with the predicted results for experimental verification. The measured performance analysis was found to match very well with the predicted results. The measured torque- and power-speed capability of the Segmented IPM machine was also compared to those of a conventional, non-segmented IPM machine of similar rating and size. The thesis also presents the optimized design of a 6kW, 12 pole Segmented Magnet IPM machine for application in the Integrated Starter Alternator (ISA) of the electric/hybrid vehicle. It can be concluded from the predicted steady-state analysis of the 6 kW, 12 pole Segmented Magnet IPM machine that it should be able to satisfy most of the required criteria of an ISA with appropriate design optimization.

Bibliography : leaves 272-277 / xiii, 277 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--University of Adelaide, Dept. of Electrical and Electronic Engineering, 1993

Thesis (M.E.) -- University of Adelaide, Department of Electrical Engineering, 1978. / Typescript (photocopy).

Thesis (M.S. in Electrical Engineering)--Naval Postgraduate School, 2004. / Thesis Advisor(s): John C. McEachen. Includes bibliographical references (p. 51-52). Also available online.

Thesis (M. Phil.)--University of Hong Kong, 1991.

Thesis (M.Eng.)--Memorial University of Newfoundland, 1999. / Bibliography: leaves 97-101.

Thesis (M.Phil.)--University of Hong Kong, 1982. / Also available in print.

Thesis (M.S.)--Florida State University, 2006. / Advisor Juan C. Ordonez, Florida State University, College of Engineering, Dept. of Mechanical Engineering. Title and description from dissertation home page (viewed Sept. 19, 2006). Document formatted into pages; contains x, 267 pages. Includes bibliographical references.

Thesis (MEng)--Stellenbosch University, 2015. / ENGLISH ABSTRACT: The growing contribution of wind energy to utility grids has sparked interest in small-scale wind turbines and thus a growing global cumulative installed capacity. Small-scale wind turbines find use in the saving of cost of electricity or for the carbon footprint reduction of small farms and small-holdings, as well as the electrification of rural communities. A goal of any wind turbine is to produce power at as low of a cost per unit energy as possible. Thus, a generator with a high power density and high efficiency is essential. The reluctance synchronous machine (RSM) is a strong competitor in this regard. Additionally, the RSM is a robust brushless topology that has good properties of manufacturability. However, studies published on the use of RSMs as generators in wind turbines is limited. This study serves to explore the performance and controllability of an RSM as a generator in a small-scale 9:2 kW wind turbine. For maximum power capture, it is desirable to have a wind turbine vary its rotor speed. However, there is a limit to the power that the generator may produce and so techniques are employed to reduce the captured power when operating above the rated wind speed. A turbine controller is developed that employs a speed-controlled maximum power point tracking (MPPT) technique for maximum power capture and soft-stalling of the blades to reduce power capture at excessive wind speeds. The RSM is modelled along with a turbine simulation model, complete with a wind source generator, to evaluate the performance of the system. Speed-controlled MPPT is known to sacrifice torque smoothness for fast tracking performance. To mitigate these harsh effects on the drivetrain, the speed reference of the generator is filtered to provide an average response to the optimal speed reference. This is shown to reduce the frequent and excessive speed, torque, and electrical power variations though optimal performance is not possible. However, any reduction on drivetrain fatigue that will maximise operation time of the turbine is considered an important gain. The RSM proves to have qualities that are applicable to wind turbine applications with its high efficiency, good manufacturability properties, low cost, and high robustness. Its higher power density over induction machines is also favourable though power electronics are required for optimal operation of the machine. / AFRIKAANSE OPSOMMING: Die groeiende bydrae van wind energie te nut roosters het aanleiding gegee tot belangstelling in kleinskaalse wind turbines en dus 'n groeiende w^ereldwye kumulatiewe geïnstalleerde kapasiteit. Kleinskaalse wind turbines vind ook gebruik in die besparing van koste van elektrisiteit, of vir die koolstofvoetspoor vermindering van klein plase en klein-hoewes, sowel as die elektrifisering van landelike gemeenskappe. Een van die doelwitte van enige wind turbine is om krag te produseer teen so laag van 'n koste per eenheid energie as moontlik. Dus, 'n kragopwekker met 'n hoë krag digtheid en hoë doeltreffendheid is noodsaaklik. Die reluktansie sinchroonmajien (RSM) is 'n sterk mededinger in hierdie verband. Daarbenewens is die RSM 'n robuuste borsellose topologie wat goeie eienskappe van vervaardigbaarheid het. Maar studies oor die gebruik van RSMs as kragopwekkers gepubliseer in die wind turbines is beperk. Hierdie studie dien om die prestasie te ondersoek en die beheerbaarheid van 'n RSM as 'n a kragopwekker in 'n klein-skaal 9:2 kW wind turbine te verken. Vir maksimum krag vang is dit wenslik dat die wind turbine sy rotor spoed wissel. Maar daar is 'n beperking op die krag wat die kragopwekker kan produseer en daarom work tegnieke gebruik om die gevange krag te verminder wanneer daar bo die gegradeerde wind spoed gewerk word. 'n Turbine beheerder word ontwikkel wat werk om 'n spoedbeheer maksimum kragpunt dop tegniek vir maksimum krag vang en die sagtestaking van die lemme krag vang deur oormatige wind spoed te verminder. Die RSM is gemodeleer saam met 'n turbine simulasie model kompleet met 'n wind bron kragopwekker om die prestasie van die stelsel te evalueer. Spoedbeheerde maksimum kragpunt dop is bekend om wringkrag gladheid vir 'n vinnige dop prestasie te offer. Om hierdie harde gevolge op die kragoorbringstelsel te versag is die spoed verwysing van die kragopwekker gefiltreer om 'n gemiddelde reaksie op die optimale spoed verwysing te verskaf. Dit word getoon om gereelde en hoë spoed, wringkrag en elektriese krag variases te verminder al is optimale prestasie nie moontlik nie. Enige afname van aandrystelsel moegheid wat operasie tyd van die turbine maksimeer word beskou as 'n belangrike gewin. Die RSM bewys eienskappe wat van toepassing is op die turbine aansoeke na aanleiding met sy hoë doeltreffendheid, goeie vervaardigbaarheid eienskappe, lae koste end ' hoë robuustheid. Sy hoër krag digtheid oor induksiemasjien is ook gunstig al is drywingselektronika nodig vir optimale werking van die masjien.

Orientador: Ana Cristina Cavalcanti Lyra / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Eletrica e de Computação / Made available in DSpace on 2018-08-13T02:43:04Z (GMT). No. of bitstreams: 1 Pereira_HevertonAugusto_M.pdf: 2867857 bytes, checksum: a8f2affcf72d938b865fc77e3f26a610 (MD5) Previous issue date: 2009 / Resumo: Nas últimas décadas as formas de transmissão de conhecimentos têm evoluído muito rapidamente, principalmente pela evolução da tecnologia da informação. A modelagem de sistemas físicos tem atingido grande complexidade, tornando as equações matemáticas difíceis de interpretação. Essa complexidade impõe um desafio no ensino dos componentes dos sistemas de energia elétrica, que pode ser superado com a utilização de ferramentas computacionais. O objetivo deste trabalho é desenvolver um aplicativo computacional didático, para simulações de estabilidade da máquina síncrona, que permita a análise da influência do controle de reativo e do sinal estabilizador na estabilidade da máquina síncrona. Além disso, é analisada a influência da reatância do transformador na estabilidade. Neste trabalho todas as análises de estabilidade têm como premissa as fronteiras de estabilidade, oscilatória e aperiódica, desenvolvidas a partir do modelo de 3ª ordem da máquina síncrona. O modelo de 3ª ordem foi desenvolvido a partir do modelo de 5ª ordem, e ambos não incluem os enrolamentos amortecedores. Uma comparação realizada entre os dois modelos mostrou grande semelhança entre os modelos de 3ª e 5ª ordem. Para o desenvolvimento da interface gráfica foi utilizado o Matlab®. A interface foi desenvolvida para maior usabilidade, onde a simulação é realizada sem necessidade do uso de linguagens de baixo nível. Assim, o foco é analisar os gráficos gerados a partir da simulação. Os cinco módulos desenvolvidos foram: simulação do modelo de 3ª ordem, comparação entre o modelo de 3ª e 5ª ordem, comparação entre ganhos de reativo, comparação entre sinais estabilizadores e comparação com e sem transformador. A inclusão de outros módulos pode ser realizada de maneira rápida, proporcionando que atualizações possam ser realizadas sem impacto ao sistema original. / Abstract: The ways to spread knowledge in the last decades have been rapidly evolved, most due to improvements on information technology. The modeling of physical systems has reached vast complexity. In advance, the mathematical equations used on these models have become harder to interpret. This complexity imposes a challenge on teaching synchronous machines and it can be managed through the use of computational resources. The purpose of this work is to develop a didactical application, that helps teaching synchronous machines stability and allow the analysis of the reactive control and stabilizing signal influences on synchronous machine stability. Additionally, the influence of the transformer reactance on the stability is analyzed. Every stability analysis included on this work has as premise the stability frontiers, oscillatory and aperiodic, developed through the synchronous machine's third order model. The 3rd order model was developed from the 5th order and none of the models include dampers winding. A comparison between the 3rd and 5th order models showed great similarity among them. Matlab® was used to develop a graphical interface and the models were simulated with the use of Simulink®. Usability was the key factor during the development of the interface, were the simulations can be done without the need of low-level languages. Thus, the focus should be analyzing the graphics generated through the simulation. The five modules developed were: 3rd order model simulation, comparison between 3rd and 5th order models, reactive gain comparison, stability signal comparisons and the comparison with and without transformer. New modules can be easily added to this work, providing new updates without affecting the original system. / Mestrado / Automação / Mestre em Engenharia Elétrica