Concerns with emissions, CO2 in particular, and energy resource associated with conventional internal combustion engine (ICE) vehicles is motivating a shift towards more electrified power-trains for road transportation, as well as other transportation applications. The modelling, characterization and design of electrified power-trains, including energy storage technologies, traction machine technologies and their associated power electronics, are discussed in this thesis. Port cranes are a special case of land transportation encompassing many of the power-train objectives found common with road based hybrid electric vehicles; here a port crane system is studied. The power flow for a typical crane loading cycle is analyzed and the value of the energy consumption and saving potential is calculated. Then alternative energy storage applications are considered for hybrid power-train configurations employing diesel engine generators, battery packs, supercapacitors (SCs), and flywheels. A hybrid rubber tyred gantry crane (RTGC) power-train model with power management is developed and the battery-SC hybrid energy storage systems are designed for both short- and long-period operation. The Induction machine (IM) is a popular technology for traction applications. Although many publications discuss IM design to realize a traction torque-speed characteristic, the IM model is studied to determine the main parameters impacting on the machine performance capability at constant torque and extended speed. Based on the model analysis, an IM design procedure for traction applications is proposed which improves machine performance capability. The machine design parameters are normalized in per unit form and hence the proposed design procedure is applicable across different ratings. In the specification and definition of vehicle power-trains, it is common (in industry) to quote data at specific operating conditions, for example, full or fixed battery terminal voltage and system temperature. The interactive influence between energy storage devices and the vehicle system is investigated. Using the all-electric Nissan Leaf power-train as a reference example, the Nissan Leaf traction system is evaluated and performance assessed by considering DC-link voltage variation from battery full state of charge (SoC) to zero SoC and temperature variations typical of an automotive application, showing that the system stated performance is reduced as battery SoC decreases. An alternative traction machine design is proposed to satisfy the vehicle target performance requirements over the complete variation of SoC. The vehicle power-train is then modified with the inclusion of a DC/DC converter between the vehicle battery and DC-link to maintain the traction system DC-link voltage near constant. A supercapacitor system is also considered for improved system voltage management. The trade-offs between the actual Nissan Leaf power-train and the redesigned systems are discussed in terms of electronic and machine packaging, and mitigation of faulted operation at high speeds. Using the Nissan Leaf interior permanent magnet (IPM) machine as the benchmark machine, an example surface permanent magnet (SPM) machine, with same design constraints, is designed and compared with the benchmark IPM machine. The phase voltage distortion of IPM and SPM machines are compared and the mechanisms are revealed. An alternative machine topology with pole shoe rotor is proposed for reduction of machine peak current rating and voltage distortion. The pole shoe topology is common in industrial variable speed drives employing constant torque regimes, but not for traction. Here, the machine with pole shoe rotor is designed to achieve traction performance. The pole shoe concept for vehicle traction is significantly different from existing practice in the electric and hybrid electric automotive industry and thus departure in standard design is a contribution of this thesis. / Thesis / Doctor of Philosophy (PhD)

Switched Reluctance Machines (SRMs) are receiving significant attention from industries in the last decade. They are extremely inexpensive, reliable and weigh less than other machines of comparable power outputs. Although the design principles of the machine are available as a concatenation of many different sources, the need for a unified, step-by-step design procedure from first principles of electromagnetics is an absolute requirement. This dissertation discusses a procedure that can be applied by engineers with a basic background in electromagnetics. Subsequent to the design of the machine, existing finite element software can do the analysis of the machine. However, this is a laborious process and the need for an analytical method is preferable to verify the design procedure before the final verification by finite elements. The analytical procedure as well as a procedure to calculate iron losses is also developed in this dissertation. A prototype machine has been developed as an example of the design process and an existing prototype is analyzed to verify the analysis procedure. The similarities between the SRM and the Permanent Magnet Brushless DC Machine (PMDBC) beg the consideration of the development of a converter that can be used to drive either machine. One such converter has been developed in this dissertation. The design of the drive for both the machines is seen to be very similar. As a consequence, a universal controller that can be used to operate both machines has been developed and implemented with a DSP. Simulations and experimental correlation for both drives have been presented. / Ph. D.

Os motores de indução monofásicos necessitam de dois enrolamentos estatóricos para criação de um campo magnético girante: um enrolamento principal e um enrolamento auxiliar. Este último tem o objetivo de criar um campo girante apenas na partida do motor, desligando-se logo em seguida, através de um interruptor centrífugo acoplado ao eixo do rotor da máquina. O objetivo deste trabalho é avaliar a influência das diferentes configurações de enrolamentos sobre as características externas do motor de indução monofásico. Sendo assim, através desta análise, pretende-se verificar se há algum benefício em seu desempenho. Neste trabalho, duas configurações de enrolamentos foram desenvolvidas e testadas em laboratório. Na primeira configuração, o enrolamento principal foi alocado na parte inferior das ranhuras. Na segunda configuração, as posições dos enrolamentos foram invertidas. As duas configurações de enrolamento foram aplicadas a um protótipo de 0,37 kW, quatro pólos. A simulação foi realizada através de um programa computacional de elementos finitos, possibilitando a extração e análise de resultados, com as densidades de fluxo nas duas configurações. Os resultados dos ensaios realizados no protótipo permitiram analisar o comportamento de grandezas como corrente elétrica, torque, potência e rendimento que são apresentados e comparados no final deste trabalho. / The single phase induction motor needs two stator windings to produce the rotating magnetic field: a main winding and an auxiliary winding. The aim of the auxiliary winding is to create the rotating electromagnetic field when the machine is starting and afterwards turned off, generally through a centrifugal switch coupled to the shaft of the machine. The main purpose of this work is to evaluate the influence that the position of the two windings have on the external characteristics of the single phase induction motor. For this purpose, two different kinds of winding configurations were carried out and simulated in a prototype. In the first configuration, the main winding was located in the bottom of the slot. In the second configuration, the positions of the windings were inverted. Performance analysis and computational simulation by Finite Element Method were carried out after the prototype 0.37 kW, four poles was prepared. In this way, through this analysis, improvements on its performance are expected. The electrical quantities such as flux density, electric current, torque, power and efficiency are compared in the end of this document.

Os motores de indução monofásicos necessitam de dois enrolamentos estatóricos para criação de um campo magnético girante: um enrolamento principal e um enrolamento auxiliar. Este último tem o objetivo de criar um campo girante apenas na partida do motor, desligando-se logo em seguida, através de um interruptor centrífugo acoplado ao eixo do rotor da máquina. O objetivo deste trabalho é avaliar a influência das diferentes configurações de enrolamentos sobre as características externas do motor de indução monofásico. Sendo assim, através desta análise, pretende-se verificar se há algum benefício em seu desempenho. Neste trabalho, duas configurações de enrolamentos foram desenvolvidas e testadas em laboratório. Na primeira configuração, o enrolamento principal foi alocado na parte inferior das ranhuras. Na segunda configuração, as posições dos enrolamentos foram invertidas. As duas configurações de enrolamento foram aplicadas a um protótipo de 0,37 kW, quatro pólos. A simulação foi realizada através de um programa computacional de elementos finitos, possibilitando a extração e análise de resultados, com as densidades de fluxo nas duas configurações. Os resultados dos ensaios realizados no protótipo permitiram analisar o comportamento de grandezas como corrente elétrica, torque, potência e rendimento que são apresentados e comparados no final deste trabalho. / The single phase induction motor needs two stator windings to produce the rotating magnetic field: a main winding and an auxiliary winding. The aim of the auxiliary winding is to create the rotating electromagnetic field when the machine is starting and afterwards turned off, generally through a centrifugal switch coupled to the shaft of the machine. The main purpose of this work is to evaluate the influence that the position of the two windings have on the external characteristics of the single phase induction motor. For this purpose, two different kinds of winding configurations were carried out and simulated in a prototype. In the first configuration, the main winding was located in the bottom of the slot. In the second configuration, the positions of the windings were inverted. Performance analysis and computational simulation by Finite Element Method were carried out after the prototype 0.37 kW, four poles was prepared. In this way, through this analysis, improvements on its performance are expected. The electrical quantities such as flux density, electric current, torque, power and efficiency are compared in the end of this document.

The overarching goal of this work is to address the design of next-generation, high torque density electrical machines through numerical optimization using an integrated thermal-electromagnetic design tool that accounts for advanced cooling technology. A parametric thermal model of electric machines was constructed and implemented using a finite difference approach incorporating an automated, self segmenting mesh generation. A novel advanced cooling technology is proposed to improve thermal transport in the machine by removing heat directly from the windings via heat exchangers located between the winding bundles. Direct winding heat exchange (DWHX) requires high convective transport and low pressure loss. The heat transfer to pressure drop tradeoff was addressed by developing empirically derived Nusselt number and friction factor correlations for micro-hydrofoil enhanced meso-channels. The parametric thermal model, advanced cooling technique, Nusselt number and friction factor correlations were combined with a parametric electromagnetic model for electric machines. The integrated thermal-electromagnetic model was then used in conjunction with particle swarm optimization to determine optimal conceptual designs. The Nusselt number correlation achieves an R² value of 0.99 with 95% of the data falling within ± 2.5% similarly the friction factor correlation achieves an R² value of 0.92 with 95% of the data falling within ± 10.2%. The integrated thermal-electromagnetic design tool, incorporating DWHX, generated an optimized 20 kW permanent magnet electric machine design achieving a torque density of 23.2 N-m/L based on total system volume.

Flywheel systems are attractive in hybrid and electric vehicles due to their ability to handle power during acceleration and braking. The combination of a flywheel device with a battery source has several advantages such as high peak power capacity, high energy density and reduction in the number of charge/discharge cycles of the battery. A flywheel based all-electric driveline is investigated in this thesis. The novelty of the system consists in the use of a double wound flywheel machine, which divides the system in two different power levels. Due to this configuration, the system becomes efficient and can handle the power developed during fast dynamical processes. The complete driveline consists of three main components: the battery, the flywheel machine and the wheel motor. The High-Power (HP) side of the driveline connects the flywheel machine to the wheel motor, whereas the Low-Power (LP) side connects the flywheel machine to the battery. The connections of different components of the system are made electrically through power converter devices. The present thesis focuses on the electrical converters and control strategies used in the flywheel based all-electric driveline. The control of power converters is responsible for the logic and functionality of the driveline, being a challenging step within this project. Different power converter topologies have been investigated: a DC/DC plus a DC/AC converter on the LP side, and an AC/DC/AC converter on the HP side. The design and assembly of the power electronics and their control scheme have been successfully implemented. Different control strategies have been suggested and a complete scaled driveline has been assembled and tested based on previous simulation results. Results have confirmed the functionality of the driveline, where smoothed output power has been obtained from the battery, whereas the flywheel handles power transients on the traction side. An average efficiency of about 87% (battery to wheels) has been obtained. The power converter systems have been shown to be efficient and robust, with control strategies able to handle the peak energy flow in the system. A regenerative braking strategy has been simulated and a wheel-to-wheel efficiency of about 80% has been estimated.

Orientador: Ernesto Ruppert Filho / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-19T04:10:37Z (GMT). No. of bitstreams: 1 Nogueira_ViniciusdeFreitasGomes_M.pdf: 1151425 bytes, checksum: 25421deb7c7d0073c31744365ccb6e53 (MD5) Previous issue date: 2011 / Resumo: Os geradores síncronos trifásicos são atualmente os mais utilizados em geração de energia elétrica em grande escala no mundo todo. Na geração de energia elétrica em pequena escala, geralmente como geração distribuída, ligada à rede de distribuição em média tensão ou até mesmo em baixa tensão, eles tem sido muito usados devido à sua principal qualidade que é a de operar em velocidade constante. Entre as suas aplicações em geração distribuída destacam-se aquelas que usam energias renováveis como em médios e pequenos aproveitamentos hidráulicos, em aproveitamentos da biomassa e nos aproveitamentos eólicos. Neste trabalho estuda-se a modelagem do gerador síncrono, estabilidade transitória utilizando os diferentes modelos de representação do gerador síncrono e o seu desempenho dinâmico em algumas situações de operação em geração distribuída com cargas lineares e com cargas não lineares, com e sem o uso de filtragem ativa / Abstract: The three-phase synchronous generators are currently the most used in generating electricity on a large scale worldwide. In generating electricity on a small scale, usually as distributed generation, connected to the distribution network or even medium voltage low voltage, they have been widely used due to its main quality is to operate at constant speed. Among its applications in distributed generation to include those using renewable energy as in medium and small hydroelectric plants, biomass and hydroelectric in the Windmill. This paper studies the modeling of the synchronous generator, transient stability using different models of representation of the synchronous generator and its dynamic performance in some situations of operation distributed generation with linear loads and nonlinear loads, with and without the use of filtering active / Mestrado / Energia Eletrica / Mestre em Engenharia Elétrica

Indiana University-Purdue University Indianapolis (IUPUI) / The purpose of this thesis is to perform modeling from different perspectives for an airgapless motor. The airgapless motor is a proposed type of electric machine whose purpose is to replace hydraulic machines in low speed high torque applications. Because of the nature of the movement for this device, modeling of this device is atypical to the modeling done with other electric machines. This thesis will present the operating principle of the airgapless motor and take an analytical approach to modeling the torque and total energy in the device. In addition, this thesis will present the power electronics necessary to drive this device and offer recommendations to maximize the torque and minimize the torque ripple. MATLAB simulations are used to verify that the conclusion of this thesis are consistent with observations made by previous publications and prototypes.

This thesis studies the brushless permanent magnet synchronous (BLPM) machine design for electric vehicle (EV) and hybrid electric vehicle (HEV) application. Different rotor topologies design, winding design, and multiphase designs are investigated and discussed. The Nissan Leaf interior permanent magnet (IPM) traction machine has been widely analyzed and there is much public domain data available for the machine. Hence, this machine is chosen as a representative benchmark design. First, the Nissan Leaf machine is analyzed via finite element analysis (FEA) and the results confirmed via published experimental test data. The procedure is then applied to all the following machine designs and results compared. Then the Nissan Leaf machine rotor is redesigned to satisfy the performance specification with sinusoidal phase current in the full range for the same performance specification and permanent magnet material. Afterword, a comparative study assessing the design and performance attributes of the Nissan Leaf IPM machine, when compared to a surface permanent magnet (SPM) machine designed within the main Nissan Leaf machine dimensional constraints. The study illustrates and concludes that both the IPM and SPM topologies have very similar capabilities with only subtle differences between the design options. The results highlight interesting manufacturing options and materials usage. The grain boundary diffusion processed (GBDP) magnets are proposed to reduce the rare earth material content in the permanent magnet machines, especially subject to high load and high temperature operating scenarios by preventing or reducing the onset of demagnetization. The design and analysis procedure of BLPM machine with GBDP magnets are put forward. In the end, the Nissan Leaf IPM machine is taken as an example to verify the analysis procedure. and the results illustrates that IPM machines with GBDP magnets can realize torque and maintain efficiency at high loads while being less prone to demagnetization. A new multi-phase synchronous reluctance machine (SRM) with good torque performance and conventional voltage source inverter is introduced for traction machine applications. Although the torque density is low compared with BLPM machine, the SRM machine gets rid of permanent magnets and achieve low torque ripple compared with switched reluctance machine when the asymmetric inverter is replaced with conventional voltage source inverter. The concentrated windings are designed and studied with both IPM and SPM rotor according to the Nissan Leaf machine requirements of performance and dimension to investigate how the concentrated windings affect the machine performance and manufacturability and cost. 9-, 12-, 15- slot concentrated windings’ stator share the same slot area with the Nissan Leaf machine distributed winding and the performance are evaluated and compared. Multi-phase concentrated windings machines with IPM and SPM rotor are designed and analyzed based on the Nissan Leaf machine specification and dimension constraints. The performance of 23-phase, 5-phase, 9-phase machine at low speed and top speed are studied and the advantages and disadvantages are compared in terms of torque quality, efficiency, and power electronic requirements. / Thesis / Doctor of Philosophy (PhD)

The electromagnetic utilization of an electrical machine can be increased by raising the current density, with a limitation resulting from the maximum permissible temperature of the winding insulation. Conventional insulating materials only have a low specific thermal conductivity, which results in large temperature gradients in the winding cross section and consequently hotspots. This article presents the development and characterization of ceramic-like composite materials based on filled polysiloxanes for the dip coating of lamination stacks and the impregnation of the winding of electrical machines. The specific equivalent thermal conductivity is determined on composite winding samples, the thermal cycle stability is examined and the microstructure is analyzed with the scanning electron microscope. The manufacturability and the partial discharge behavior are examined based on test samples. The results of tests on an electric traction machine are used to show the potential for increasing the power density.