De nos jours, les véhicules électriques et hybrides ont suscité un très grand intérêt en raison de préoccupations environnementales et énergétiques. Dans ces véhicules, les machines électriques utilisées sont des machines conventionnelles asynchrones et synchrones à aimants permanents. La machine à réluctance variable est une technologie candidate potentielle pour les chaînes de traction électriques et hybrides. Cette machine conçue sans aimants et redondante peut réunir la robustesse et le faible coût de la machine asynchrone aux bonnes performances de la machine synchrone à aimants permanents. Dans ce contexte, le premier objectif de cette thèse est de proposer des stratégies de commandes robustes de la machine à réluctance variable par la prise en compte des contraintes des chaînes de traction électriques en vue de réaliser une étude comparative des performances. Dans cette étude, les commandes proposées sont les commandes classiques de type PI, les commandes par mode glissant et les commandes par mode glissant d'ordre supérieur. Le deuxième objectif consiste à développer des observateurs d'état pour la commande sans capteur de position mécanique de la machine à réluctance variable. Des observateurs robustes basés sur la théorie du filtre de Kalman étendu et les modes glissants sont synthétisés pour atteindre cet objectif. Enfin, le troisième objectif est de faire une analyse des défauts électriques de type circuit ouvert de l'étage électronique de puissance par l'approche signal afin de développer une méthodologie de détection et de localisation automatique de ces défauts. / Nowadays, electric and hybrid vehicles are gaining increased attention due to environmental and energy concerns. In these vehicles, the electrical machines used are the conventional machines, namely induction and permanent magnet synchronous machines. The switched reluctance machine is a potential candidate technology for electric and hybrid drivetrains. This machine designed without magnets and redundant windings, can combine the robustness and low cost of induction machines to the good performance of permanent magnet synchronous machines. In this context, the first objective of this thesis is to propose robust control strategies of the switched reluctance machine, taking into account the constraints of electric vehicles in order to make a comparative performance study. In this study, PI control, sliding mode control and higher order sliding mode control are proposed. The second objective is to develop state observers for sensorless control. Robust observers based on extended Kalman filter theory and sliding modes are synthesized to achieve this goal. Finally, the third objective is to make an analysis of electrical open-circuit faults of the electronic power stage using the signal approach in order to develop a methodology of automatic fault isolation.

Although the design principles of the Switched Reluctance Machines (SRMs) are available in different fragments in numerous bibliography positions, there no exists the complex design procedure of whole drive system taking into account the SR Machine, control system and supply device as well. The hybrid design method for SRM drives with application of new analytical calculation methods, finite element method and simulation models is proposed in this thesis. The calculation/design system is characterised by important effectivity and reliability. The new possibilities in analytical determination of saturation effects and core losses under various modes of control, including sensorless method, are also taken into account. The correctness of the proposed design algorithms are verified by laboratory tests made on three motor prototypes manufactured in industry for concrete application. This dissertation provides the elements indispensable for more accurate and complex analysis and design of drives with switch reluctance motors. The elements of electrical motor and control system design as well as the considerations on the choice of supply device and controller subsystems are jointed in the thesis for final receiving of the design tool for considered industrial drive system.

In this thesis, after a comprehensive literature review on different conventional and predictive torque control strategies for switched reluctance motor (SRM) drives, two online methods and one offline multi-objective optimization-based method are proposed to extend the operating speed range of finite control set model predictive torque control (FCS-MPTC) for SRM by adaptively controlling the commutation angles in the entire speed range. Furthermore, a method is proposed to minimize the steady state torque tracking error of FCS-MPTC for SRM drives. The incapability of the conventional FCS-MPTC in controlling the commutation angles, which is considered as one of the main drawbacks of the conventional FCS-MPTC, limits its application for high-speed torque control of SRM drives. The phase turn-off angle is always selected to be close to the aligned position with the conventional FCS-MPTC regardless of the operating speed. However, commutation angle advancement is required for high-speed torque control of SRM drives to limit the negative phase torque resulting from the current tail after the turn-off angle in the generating region. Excessive negative torque with the conventional FCS-MPTC at higher speeds can result in a degraded performance with high rms current, low average torque, high torque ripple, and reduced efficiency. The phase turn-off angle can be adaptively controlled as speed changes with the first online commutation angle control strategy proposed in this thesis. This method is based on predicting the free-wheeling phase current in an extended time interval which is much bigger than the prediction horizon of FCS-MPTC. The second online turn-off angle control method is also proposed by improving the optimality condition defined for determining the optimal turn-off angle. The optimality condition is determined by calculating the work done by the conducting phase after the phase is turned off. The weighting factor of the objective function of FCS-MPTC is kept constant with both proposed online methods. An offline multi-objective optimization-based strategy is proposed to determine the globally optimal turn-off angle and the weighting factor in the entire operating torque and speed ranges. The effectiveness of both proposed online methods and the offline commutation angle control strategy is verified using simulations and experimental results. The results are also compared to the conventional FCS-MPTC and the indirect average torque control with optimized conduction angles which is considered as one of the main conventional torque control strategies for SRM drives. In order to minimize the torque tracking error as a result of either parameter uncertainties or tracking multiple objectives with a single objective function with weighting factors, a method is proposed which is based on updating the reference torque at each sample time by calculating the average torque tracking error in the previous sample times. The validity of the proposed method is verified using simulations. / Thesis / Doctor of Philosophy (PhD)

No description available.

Position estimation using only active phase voltage and current is presented to perform high accuracy position sensorless control of a SRM drive. By extracting the amplitude of the first switching harmonic terms of phase voltage and current for a PWM period through Fourier analysis, flux-linkage and position are estimated without external hardware circuitry such as a modulator and demodulator, resulting in increasing cost, as well as large position estimation error produced when the motional back emf is ignored near zero speed. Hence the proposed position estimation scheme covers the entire speed range including the standstill under various loads and it has high resolution information depending on switching frequency. Fourier series and Fast Fourier transform are employed to decompose the phase voltage and current into its first switching harmonic. A two-phase SRM drive system, consisting of an asymmetrical converter and a conventional closed-loop PI current controller, is utilized to validate the performance of the proposed position estimation scheme in comprehensive operating conditions. The estimated values very closely track the actual values in dynamic simulations and experiments. It is shown that the proposed position estimation scheme using Fourier analysis is sufficiently accurate and works satisfactorily at various operating points. This research also proposes an accurate self-inductance measurement method. In general, when applying circulating currents within the body of a ferromagnetic material under conditions of a time varying magnetic flux, the effects of eddy current losses and resistance changes due to heating decrease the magnetic field strength and thereby the reduced magnetic field decreases the magnetic flux-linkage of SRM. These losses make a challenge to the measurement of magnetic characteristics of SRM. These motives lead to propose a measurement methodology based on 60 Hz sinusoidal excitation using a variable AC power supply, which provides an alternative to time domain integration approaches for self-inductance or flux-linkage measurement as well as eliminates error arising from thermal and eddy currents effects. The validation of the proposed method is verified with the correlation between the measurement and FEA results of flux-linkage. Furthermore, this research proposes the solutions for low cost and high efficiency drive systems, consisting of a split AC converter and a two-phase SRM. Its performance is analyzed and verified with experiments at the rated speed under various loads. It is believed that this drive system combined with the proposed position estimation scheme using Fourier analysis is a strong contender to be a low cost motor drive system with single switch per phase having comparable efficiency and acoustic noise level as an asymmetric drive system. / Ph. D.

Linear switched reluctance motor (LSRM) drives are investigated and proved as an alternative actuator for vertical linear transportation applications such as a linear elevator. A one-tenth scaled prototype elevator focused on a home elevator with LSRMs is designed and extensive experimental correlation is presented for the first time. The proposed LSRM has twin stators and a set of translator poles without back-iron. The translators are placed between the two stators. The design procedures and features of the LSRM and the prototype elevator are described. The designed LSRM is validated through a finite element analysis (FEA) and experimental measurements. Furthermore, a control strategy for the prototype elevator is introduced consisting of four control loops, viz., current, force, velocity, and position feedback control loops. For force control, a novel force distribution function (FDF) is proposed and compared with conventional FDFs. A trapezoidal velocity profile is introduced to control vertical travel position smoothly during the elevator's ascent, descent, and halt operations. Conventional proportional plus integral (PI) controller is used for the current and velocity control loops and their designs are described. The proposed control strategy is dynamically simulated and experimentally correlated. Analytical and experimental results of this research prove that LSRMs are one of the strong candidates for ropeless linear elevator applications. However, the proposed FDF is assuming that the feedback current signals are ideal currents indicating actual phase currents without any measurement disturbances mainly arising from sensor noise, DC-link voltage ripple, measurement offset, and variations in the plant model. Meanwhile, real control systems in industry have measurement disturbance problems. Phase current corrupted by measurement disturbances increases torque or force ripple, acoustic noise and EMI. Therefore, this dissertation also presents a novel current control method to suppress measurement disturbances without extra hardware. The controller is based on an extended state observer (ESO) and a nonlinear P controller (NLP). The proposed method does not require an accurate mathematical model of system and can be implemented on a low-cost DSP controller. The proposed ESO is exploited to estimate the measurement disturbances on measured phase currents, and the proposed NLP compensates for the measurement disturbances estimated by the ESO. The performance of the proposed current control is validated through extensive dynamic simulations and experiments. Moreover, this rejection of measurement disturbances results in a reduction of force ripple and acoustic noise. Due to superior and robust current control performance, it is believed that the proposed method can be successfully applied into other motor drive systems to suppress measurement disturbances with the same promising results without extra hardware. / Ph. D.

A finalidade deste trabalho é desenvolver uma contribuição ao projeto de geradores e motores de relutância chaveados. A primeira etapa do projeto consiste no dimensionamento inicial da máquina através de métodos analíticos convencionais [01]para, em seguida, desenvolver o seu refinamento usando o Método dos Elementos Finitos acoplado com as equações de circuitos elétricos. Inicialmente, é apresentada uma abordagem atualizada dos aspectos construtivos e operacionais deste equipamento, comuns aos dois modos de funcionamento, bem como dos aspectos relevantes da metodologia computacional utilizada. Apresentam-se, em seguida, os resultados das simulações conduzidas para a obtenção das características de torque estático, do fluxo concatenado e das indutâncias, em função da posição angular do rotor e da corrente, as suas implicações no projeto e a sua utilização para a definição das condições operacionais dinâmicas a serem simuladas. Em seguida, são apresentados os resultados das simulações em regime permanente e em transitórios operacionais da máquina elétrica funcionando de uma forma integrada com o seu conversor eletrônico dedicado. No fechamento deste trabalho, estes resultados são discutidos e comparados com alguns ensaios realizados. Apresenta-se também os possíveis desdobramentos para a continuidade do projeto deste tipo de equipamento. O enfoque essencial deste trabalho é a máquina elétrica e os seus resultados propiciam também uma orientação para a definição dos requisitos de projeto do conversor eletrônico e do sistema de controle. / This work aims to provide a contribution to the project of switched reluctance generators and motors. The first stage of the project consists of initial dimensioning of the machine through conventional analytical methods[1] followed by its refinement by using the Finite-element Method coupled with circuit equations. An updated approach on the constructive and operational aspects common to both the ways of the equipment, as well as relevant aspects of the computational methodology used are initially presented. Results of simulations carried out to obtain torque characteristics, flux-linkage and inductance, as a function of angular position of rotor and current, their implications in the project and their use to define dynamic operational condition to be simulated are then showed. Sequentially, results of the steady-state and transients operational simulations of the electric machine working in an integrated way with its dedicated electronic converter are presented. In the closing of this work, these results are discussed and compared to some of the tests performed. Related subjects for continuation of the project of this type of equipment are also presented. The main focus of this work is the electric machine and its results also provide an orientation to the definition of requirements to the project of electronic converter and control system.

A finalidade deste trabalho é desenvolver uma contribuição ao projeto de geradores e motores de relutância chaveados. A primeira etapa do projeto consiste no dimensionamento inicial da máquina através de métodos analíticos convencionais [01]para, em seguida, desenvolver o seu refinamento usando o Método dos Elementos Finitos acoplado com as equações de circuitos elétricos. Inicialmente, é apresentada uma abordagem atualizada dos aspectos construtivos e operacionais deste equipamento, comuns aos dois modos de funcionamento, bem como dos aspectos relevantes da metodologia computacional utilizada. Apresentam-se, em seguida, os resultados das simulações conduzidas para a obtenção das características de torque estático, do fluxo concatenado e das indutâncias, em função da posição angular do rotor e da corrente, as suas implicações no projeto e a sua utilização para a definição das condições operacionais dinâmicas a serem simuladas. Em seguida, são apresentados os resultados das simulações em regime permanente e em transitórios operacionais da máquina elétrica funcionando de uma forma integrada com o seu conversor eletrônico dedicado. No fechamento deste trabalho, estes resultados são discutidos e comparados com alguns ensaios realizados. Apresenta-se também os possíveis desdobramentos para a continuidade do projeto deste tipo de equipamento. O enfoque essencial deste trabalho é a máquina elétrica e os seus resultados propiciam também uma orientação para a definição dos requisitos de projeto do conversor eletrônico e do sistema de controle. / This work aims to provide a contribution to the project of switched reluctance generators and motors. The first stage of the project consists of initial dimensioning of the machine through conventional analytical methods[1] followed by its refinement by using the Finite-element Method coupled with circuit equations. An updated approach on the constructive and operational aspects common to both the ways of the equipment, as well as relevant aspects of the computational methodology used are initially presented. Results of simulations carried out to obtain torque characteristics, flux-linkage and inductance, as a function of angular position of rotor and current, their implications in the project and their use to define dynamic operational condition to be simulated are then showed. Sequentially, results of the steady-state and transients operational simulations of the electric machine working in an integrated way with its dedicated electronic converter are presented. In the closing of this work, these results are discussed and compared to some of the tests performed. Related subjects for continuation of the project of this type of equipment are also presented. The main focus of this work is the electric machine and its results also provide an orientation to the definition of requirements to the project of electronic converter and control system.

With the rapid growth of air travel, concerns about the emissions of greenhouse gas emissions resulting from the air transportation sector are growing. Although the current battery technologies might not be adequate for all-electric regional aircraft, the energy density of the current battery technologies could be adequate to electrify light-sport aircraft used for training and recreation. Due to the nature of the propeller load and noise isolation of the cabin, switched reluctance motors can be an excellent candidate for the propulsion system of electrified light-sport aircraft. The proposed SRM is designed to replace a 70 kW permanent magnet synchronous motor used in the aerospace industry with similar volume constraints and operational requirements. In order to meet the high-power density requirements of this application, a design framework is proposed which includes several layers of the design process. The design objectifies are the average torque, torque ripple, and radial forces by integrating the control and geometry design into the proposed framework. A comprehensive design process is carried out with the proposed framework, and a detailed coil design process is performed. The rotor cut-outs are designed to reduce the weight of the motor. The thermal performance of the motor has been analyzed for the calculated motor losses and the cooling system constraints. / Thesis / Master of Applied Science (MASc)

Este trabalho se insere num contexto de desenvolvimento da capacitação para aplicações de motores de relutância chaveados, com ênfase aos aspectos eletromagnéticos do acionamento. Inicialmente, são apresentados os principais aspectos construtivos do motor e de funcionamento do seu conversor. São discutidos os fluxos de energia do acionamento e sao apresentadas as suas características operacionais, bem como as possibilidades para o seu controle. Foi desenvolvida uma metodologia de projeto embasada numa formulação empírica e no método dos elementos finitos, implementado através do programa flux2d. Desta forma, foi projetado um protótipo para desenvolver meio newton-metro a três mil rotações por minuto. A formulação empírica baseia-se na adoção de diversas hipóteses simplificadoras do circuito ferromagnético. O método dos elementos finitos foi empregado com a finalidade da obtenção de um refinamento do dimensionamento do motor. O protótipo projetado foi fabricado e testado. Os objetivos dos ensaios foram a confrontação com os diversos valores calculados no projeto e a verificação do seu desempenho em diversas condições de carga. Finalizando o trabalho, os resultados obtidos são analisados, ressaltando-se os aspectos relevantes ocorridos durante o seu desenvolvimento. São também apresentadas, as atividades subsequêntes previstas. / This work is related to the development activities of switched reluctance motors, mainly on their electromagnetic characteristics. The motor\'s basic construction features and the converter\'s operation characteristics are showed, as well as, the energy flows, performance aspects and the effects of the control parameters. The principal elements of motor desigm are discussed. A method of design is developed based on empirical formulas and on finite elements method (using the software FLUX2D). Thus, a prototype was designed with ratings of 0,5 Nm at 3000 rpm. The empirical formulas are developed on a simplified model of the motor and taking into account the referred author\'s experience. The finite elements method was used with the aim of getting a design refinement, as well as, the static torque characteristics, inductances and flux as a function of rotor position and current. The prototype was built and tested. The tests were conducted to compare the actual with the designed parameters and to evaluate the performance characteristics. Finally, the results are analysed and the main facts observed during the development of the work are reported. The next planned activities are also showed.