Dissertations / Theses on the topic 'Machine vector control'
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Sokola, Matija. "Vector control of induction machines using improved machine models." Thesis, Liverpool John Moores University, 1998. http://researchonline.ljmu.ac.uk/4899/.
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Ozcelik, Eray. "Speed Sensorless Vector Control Of Induction Machine." Master's thesis, METU, 2005. http://etd.lib.metu.edu.tr/upload/2/12606063/index.pdf.
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Focus of this work is closed-loop speed control of an induction machine based on direct field-oriented control (DFOC) algorithm, using estimates of speed and flux observers which utilize only stator current and voltage. Theoretical bases of the algorithms are explained in detail and their performances are investigated with simulations and experiments.
Field Orientated Control is based on projections which transform a threephase time and speed dependent system into a two co-ordinate time invariant system. These projections lead to a structure similar to that of a DC machine control. Transformations are done in synchronous frame alligned to d-axis of rotor flux. So rotor flux position must be known accurately to make these transformations. Degined flux observer, in which voltage model is assisted by current model via a closed-loop to compensate voltage model&rsquos disadvantages, estimates the position of the rotor flux. Obtaining adequate torque control via FOC, speed loop is closed using conventional PI regulators. Speed feedback is necessary to complete control loop. Model Reference Adaptive System is studied as a speed estimator. Reactive power scheme is applied to MRAS algorithm to estimate rotor speed. In this study, the direct (rotor) flux oriented control system with flux and speed estimators is described and tested in real-time with the starter kit named TMS320F2812 eZdsp DSK and the Embedded Target for the TI C2000 DSP tool of Matlab
3
Aleti, Kalyan Reddy. "E-quality control a support vector machines approach /." To access this resource online via ProQuest Dissertations and Theses @ UTEP, 2008. http://0-proquest.umi.com.lib.utep.edu/login?COPT=REJTPTU0YmImSU5UPTAmVkVSPTI=&clientId=2515.
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Sharaf-Eldin, Thanaa. "Design and control of a synchronous reluctance machine drive." Thesis, Heriot-Watt University, 1999. http://hdl.handle.net/10399/1201.
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Liu, Yu. "SLOTLESS SIX-PHASE BRUSHLESS DC MACHINE DESIGN AND STEPPING VECTOR CONTROL." The Ohio State University, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=osu1440086585.
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Mascarenhas, Manuel Maria Brás Pereira. "Speed control of induction machine based on direct torque control method." Master's thesis, Faculdade de Ciências e Tecnologia, 2013. http://hdl.handle.net/10362/9957.
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Dissertação para obtenção do Grau de Mestre em
Engenharia Electrotécnica e de ComputadoresMulti-level converters have been receiving attention in the recent years and have been proposed as the best choice in a wide variety of medium voltage applications. They enable a commutation at substantially reduced voltages and an improved harmonic spectrum without a series connection of devices, which is the main advantage of a multi-level structure. The use of multi-level inverters contributes to the performances amelioration of the induction machine control. In fact, the use of three level inverter (or multilevel inverter) associated with DTC control can contribute to more reducing harmonics and the ripple torque and to have a high level of output voltage. A variation of DTC-SVM with a three level neutral point clamped inverter is proposed and discussed in the literature. The goal of this project is to study, evaluate and compare the DTC and the proposed DTC-SVM technique when applied to induction machines through simulations. The simulations were carried out using MATLAB/ SIMULINK simulation package. Evaluation was made based on the drive performance, which includes dynamic torque and flux responses, feasibility and the complexity of the systems.
7
Hedberg, Rikard. "Tree species classification using support vector machine on hyperspectral images." Thesis, Linköping University, Department of Electrical Engineering, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-54648.
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For several years, FORAN Remote Sensing in Linköping has been using pulseintense laser scannings together with multispectral imaging for developing analysismethods in forestry. One area these laser scannings and images are used for is toclassify the species of single trees in forests. The species have been divided intopine, spruce and deciduous trees, classified by a Maximum Likelihood classifier.This thesis presents the work done on a more spectrally high-resolution imagery,hyperspectral images. These images are divided into more, and finer gradedspectral components, but demand more signal processing. A new classifier, SupportVector Machine, is tested against the previously used Maximum LikelihoodClassifier, to see if it is possible to increase the performance. The classifiers arealso set to divide the deciduous trees into aspen, birch, black alder and gray alder.The thesis shows how the new data set is handled and processed to the differentclassifiers, and shows how a better result can be achieved using a Support VectorMachine.
8
Wong, Hang Cheong. "Design and experimental evaluation of predictive engine air-ratio control using relevance vector machine." Thesis, University of Macau, 2009. http://umaclib3.umac.mo/record=b2182947.
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Zhang, Yuan. "Sensorless Vector Control and Field Weakening Operation of Permanent Magnet Synchronous Machines." The Ohio State University, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=osu1291219704.
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Garg, Aditie. "Designing Reactive Power Control Rules for Smart Inverters using Machine Learning." Thesis, Virginia Tech, 2018. http://hdl.handle.net/10919/83558.
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Due to increasing penetration of solar power generation, distribution grids are facing a number of challenges. Frequent reverse active power flows can result in rapid fluctuations in voltage magnitudes. However, with the revised IEEE 1547 standard, smart inverters can actively control their reactive power injection to minimize voltage deviations and power losses in the grid.
Reactive power control and globally optimal inverter coordination in real-time is computationally and communication-wise demanding, whereas the local Volt-VAR or Watt-VAR control rules are subpar for enhanced grid services. This thesis uses machine learning tools and poses reactive power control as a kernel-based regression task to learn policies and evaluate the reactive power injections in real-time. This novel approach performs inverter coordination through non-linear control policies centrally designed by the operator on a slower timescale using anticipated scenarios for load and generation. In real-time, the inverters feed locally and/or globally collected grid data to the customized control rules. The developed models are highly adjustable to the available computation and communication resources. The developed control scheme is tested on the IEEE 123-bus system and is seen to efficiently minimize losses and regulate voltage within the permissible limits.Master of Science
11
Anghel, Cristian. "Sensorless Flux Vector Control for a Permanent Magnet Synchronous Machine with cylindrical rotor under severe starting conditions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1997. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape11/PQDD_0023/MQ51613.pdf.
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Ertugrul, Baris Tugrul. "Sensorless Vector Control Of Induction Motor Based On Flux And Speed Estimation." Master's thesis, METU, 2008. http://etd.lib.metu.edu.tr/upload/12610297/index.pdf.
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The main focus of the study is the implementation of techniques regarding flux estimation and rotor speed estimation by the use of sensorless closed-loop observers. Within this framework, the information about the mathematical representation of the induction motor, pulse width modulation technique and flux oriented vector control techniques together with speed adaptive flux estimation &ndasha kind of sensorless closed loop estimation technique- and Kalman filters is given. With the comparison of sensorless closed-loop speed estimation techniques, it has been attempted to identify their superiority and inferiority to each other by the use of simulation models and real-time experiments. In the experiments, the performance of the techniques developed and used in the thesis has been examined under extensively changing speed and load conditions. The real-time experiments have been carried out by the use of TI TMS320F2812 digital signal processor, XILINX XCS2S150E Field Programmable Gate Array (FPGA), control card and the motor drive card Furthermore, Matlab &ldquo
Embedded Target for the TI C2000 DSP&rdquo
and &ldquo
Code Composer Studio&rdquo
software tools have been used. The simulations and experiments conducted in the study have illustrated that it is possible to increase the performance at low speeds at the expense of increased computational burden on the processor. However, in order to control the motor at zero speed, high frequency signal implementation should be used as well as a different electronic hardware.
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Lee, Siu-keung, and 李少強. "Reinforcement learning for intelligent assembly automation." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2002. http://hub.hku.hk/bib/B31244397.
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Ouyang, Dingxin. "Intelligent Road Control System Using Advanced Image Processing Techniques." University of Toledo / OhioLINK, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1352749656.
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Bouzekri, Hacène. "Contribution à la commande des machines synchrones à aimants permanents." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL054N.
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Ce mémoire est consacré au développement de structures de régulation de courant des machines synchrones à aimants permanents (MSAP). Le premier volet de notre travail concerne la commande 120. Afin d'éliminer les surtensités qui apparaissent pendant les commutations d'une phase sur l'autre, à basse vitesse, une commande basée sur la mesure de la somme des courants des diodes du haut et des transistors du bas est proposée. Concernant les ondulations du couple engendrées par les formes d'ondes des FEM, nous avons proposé une stratégie de commande des courants de la machine dans un repère (alpha, beta) lié au stator permettant de les minimiser. Afin de minimiser les creux de couple qui apparaisse à grande vitesse, une commande fondée sur le contrôle de décroissance du courant commuté est introduite. Le deuxième volet de cette thèse concerne la commande vectorielle des MSAP et sa décentralisation. En premier, nous avons proposé une commande qui permet le contrôle du vecteur courant imposé par l'onduleur, avec deux régulateurs à hystérésis. Cette technique permet de réduire la fréquence de commutation et de contrôler les courants de la machine en amplitude et en phase d'une manière instantanée. Ensuite, une structure de contrôle des courants id et iq de la machine par des régulateurs à logique floue, utilisant des règles d'entrées/sorties linéaires, est introduite. Les régulateurs synthétisés sont indépendants des paramètres de la machine, et le contrôle de id et iq se fait d'une manière décentralisée
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Castro, Allan Gregori de. "Controle preditivo Finite Control-Set aplicado à máquina síncrona com ímã permanente no rotor." Universidade de São Paulo, 2017. http://www.teses.usp.br/teses/disponiveis/18/18153/tde-24042017-104320/.
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Ondulações de torque devido à comutação de fases é apontada como a principal desvantagem do método de controle 6 pulsos convencional do motor síncrono de ímã permanente no rotor com força contra-eletromotriz trapezoidal. Para reduzir essas ondulações, diferentes estratégias de controle vetorial dessa máquina são apresentadas na literatura. Nesse trabalho é proposto e analisado o controle vetorial dessa máquina utilizando uma malha de controle de corrente baseada no Finite Control-Set Model-based Predictive Control (FCS-MPC). Como resultado, a estrutura de controle vetorial proposta é capaz de reduzir as ondulações de torque de comutação e também aquelas provenientes de imperfeições da força contraeletromotriz trapezoidal. Esse resultado é atingido sem a alteração da estrutura do conversor, adição de circuito ou alteração na tensão de barramento. Em termos de desempenho dinâmico, são demonstradas a rápida dinâmica de torque sem necessidade de sintonia ou projeto de ganhos de controlador e dinâmica desacoplada das variáveis de controle sem necessidade de cálculo de termos de desacoplamento. Esses resultados apontam vantagens sobre recentes propostas na literatura baseada em controladores lineares. Também é implementado uma estratégia de melhoria de desempenho do FCS-MPC baseado na inclusão do conceito de ciclo de trabalho. Essa abordagem permite reduzir significativamente, em baixa velocidade, a banda de ondulação da corrente de estator e torque da máquina, demonstrando uma melhoria em relação ao FCS-MPC sem ciclo de trabalho.Torque ripples due to phase commutation are pointed to the main drawback of 120 degree 6 step control of synchronous motor with trapezoidal back electromotive force (back EMF). To reduce these ondulations, different vector control strategies are presented in the literature. This study proposes and analyzes the application of the Finite Control-Set Model-based Predictive Control in the current loop of vector control strategy of permanent magnet synchronous motor with trapezoidal back EMF. As a result, the control structure reduces the torque ripple comming from phase commutation and back EMF shape imperfections. This result is achieved without changing the converter topology, the DC link voltage or including aditional circuit. Concerning to dynamic response, the proposed control strategy offers fast torque dynamics without gain tunning needed and decoupled dynamic of variable control. Furthermore, it is implemented an improvement approach to FCS-MPC based on duty-cycle concept. This strategy reduces significantly the torque ripple in low speed range, demonstrating an advance over conventional FCS-MPC.
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Kruger, Gert Lodewikus. "Implementation and evaluation of V/f and vector control in high–speed PMSM drives / Kruger G.L." Thesis, North-West University, 2011. http://hdl.handle.net/10394/7609.
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The McTronX research group, at the Potchefstroom campus of the North–West University, has
been researching Active Magnetic Bearings (AMBs). A fully suspended, flywheel energy storage
system (FESS) has been developed. Due to excessive unbalance on the rotor, the motor drive
could not be tested up to its rated speed. In the interim, until the rotor can be balanced and
other rotor dynamic effects have been investigated, the group decided that the existing drive
control should be improved and tested on a high–speed permanent magnet synchronous motor
(PMSM), using normal roller element bearings.
In order to test the motor control a second (identical) PMSM, mechanically coupled to the
former, operates in generator mode which serves as the torque load. Two different control algorithms,
namely V/f and vector control, are designed and implemented on a rapid control
prototyping system, i.e. dSPACE®. The V/f control is an open–loop, position sensorless technique,
whilst the vector controller makes use of a position sensor.
From the design and implementation it became clear that the vector control is more robust,
in the sense that it is less sensitive on parameter variations and disturbances. It can start up
reliably even under full load conditions.
The V/f control is an attractive alternative to the vector control, especially in AMB systems,
where it may be difficult to mount the position sensor, has to operate in a hazardous environment
not suited to the sensor or could degrade the reliability of the AMB system. The cost of the
position sensor is not really a concern compared to the cost of an AMB system. The V/f control
is more suited to fan and pump applications, which has a low dynamic requirement. The V/f
control has high startup currents and is not recommended for applications requiring a high
starting torque or fast acceleration during operation.
The inverter, which drives the PMSM, also had to be developed. With regard to the motor
control, the effects of inverter non–idealities had to be accounted, especially for the V/f control.
The implemented control algorithms were tested up to 20 krpm. Discrepancies between the expected
and actual results are discussed. Overall, the controllers performed as desired. Generally,
the project goals have been reached satisfactorily.Thesis (M.Ing. (Computer and Electronic Engineering))--North-West University, Potchefstroom Campus, 2011.
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Zhang, Zai Yong. "Simultaneous fault diagnosis of automotive engine ignition systems using pairwise coupled relevance vector machine, extracted pattern features and decision threshold optimization." Thesis, University of Macau, 2011. http://umaclib3.umac.mo/record=b2493967.
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Esteves, Lucas Mangili [UNESP]. "Acionamento de motor de indução trifásico, sujeito a falhas, utilizando controle com estrutura variável e modos deslizantes." Universidade Estadual Paulista (UNESP), 2017. http://hdl.handle.net/11449/148779.
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Este trabalho apresenta uma análise do motor de indução trifásico (MIT), que é um dos motores mais utilizados em aplicações industriais, e de diferentes metodologias de controle de velocidade aplicadas para este tipo de motor. A princípio realizou-se um estudo do funcionamento do MIT sem nenhum tipo de controle, para somente depois analisar-se tanto técnicas clássicas e já bastante difundidas no controle deste tipo de máquina como também um tipo específico de controlador robusto, a fim de utilizá-lo para substituir os controladores clássicos na intenção de obter-se um desempenho superior. O controlador robusto escolhido foi do tipo com Estrutura Variável e Modos Deslizantes (CEV-MD). Este trabalho foca no estudo do Controle Vetorial Indireto com Orientação sobre o Fluxo do Rotor, sendo utilizados juntamente deste método um controlador clássico (do tipo PI, Proporcional Integral) e o controlador robusto projetado (do tipo CEV-MD), no intuito de realizar-se uma comparação entre o desempenho dos dois controladores mediante diferentes condições de operação, incluindo-se variação de parâmetros do motor e falhas de queda de tensão nos terminais da máquina. Todos os estudos e projetos resultaram em um conjunto de simulações no ambiente MATLAB/Simulink, a partir das quais constatou-se que o controlador robusto projetado apresentou um desempenho um pouco superior ao do PI, tanto no controle da velocidade quanto em relação a tolerar as falhas de queda de tensão.
This paper presents a three phase induction motor analysis, one of the most used machines in industries applications, and also shows different speed control methods for this kind of machine. At first a study about the IM (induction motor) was made without any control technique, and then an analysis of the classic and well known methods is presented, as well as an analysis of a robust controller, in order to replace the classic controllers by this one and achieve better performance. The chosen robust controller was a Variable Structure Controller with Sliding Mode. This paper focus is the study of the Indirect Vector Control with Rotor Orientation, which was used along a classic controller (PI – Proportional Integral) and the above proposed robust controller, in order to make a balance between both considering several operational conditions, including parameters variation and a particular fault (voltage drops on the motor terminals). All the analysis culminated in a set of simulations on the MATLAB/Simulink ambient, from which it was observed that the proposed robust controller showed a better performance than the PI, both on the speed control and the voltage drops faults tolerance.
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Esteves, Lucas Mangili. "Acionamento de motor de indução trifásico, sujeito a falhas, utilizando controle com estrutura variável e modos deslizantes /." Ilha Solteira, 2017. http://hdl.handle.net/11449/148779.
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Orientador: José Paulo Fernandes GarciaResumo: Este trabalho apresenta uma análise do motor de indução trifásico (MIT), que é um dos motores mais utilizados em aplicações industriais, e de diferentes metodologias de controle de velocidade aplicadas para este tipo de motor. A princípio realizou-se um estudo do funcionamento do MIT sem nenhum tipo de controle, para somente depois analisar-se tanto técnicas clássicas e já bastante difundidas no controle deste tipo de máquina como também um tipo específico de controlador robusto, a fim de utilizá-lo para substituir os controladores clássicos na intenção de obter-se um desempenho superior. O controlador robusto escolhido foi do tipo com Estrutura Variável e Modos Deslizantes (CEV-MD). Este trabalho foca no estudo do Controle Vetorial Indireto com Orientação sobre o Fluxo do Rotor, sendo utilizados juntamente deste método um controlador clássico (do tipo PI, Proporcional Integral) e o controlador robusto projetado (do tipo CEV-MD), no intuito de realizar-se uma comparação entre o desempenho dos dois controladores mediante diferentes condições de operação, incluindo-se variação de parâmetros do motor e falhas de queda de tensão nos terminais da máquina. Todos os estudos e projetos resultaram em um conjunto de simulações no ambiente MATLAB/Simulink, a partir das quais constatou-se que o controlador robusto projetado apresentou um desempenho um pouco superior ao do PI, tanto no controle da velocidade quanto em relação a tolerar as falhas de queda de tensão.
Mestre
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Baccherini, Simona. "Pattern recognition methods for EMG prosthetic control." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2016. http://amslaurea.unibo.it/12033/.
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In this work we focus on pattern recognition methods related to EMG upper-limb prosthetic control. After giving a detailed review of the most widely used classification methods, we propose a new classification approach. It comes as a result of comparison in the Fourier analysis between able-bodied and trans-radial amputee subjects. We thus suggest a different classification method which considers each surface electrodes contribute separately, together with five time domain features, obtaining an average classification accuracy equals to 75% on a sample of trans-radial amputees. We propose an automatic feature selection procedure as a minimization problem in order to improve the method and its robustness.
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Trigui, Rochdi. "Motorisation asynchrone pour véhicules électriques : modélisation, optimisation et évaluation." Vandoeuvre-les-Nancy, INPL, 1997. http://www.theses.fr/1997INPL064N.
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Notre travail a porté sur la contribution à la conception d'un outil modulaire pour la simulation de véhicules électriques et hybrides sur des trajets d'usage réel. Notre apport a concerné plus précisément la motorisation asynchrone dont le modèle proposé ici tient compte des contraintes imposées à l'entrée et à la sortie du moteur électrique par le type d'usage du véhicule. En effet, une étude préliminaire concernant l'usage réel d'un véhicule utilitaire électrique de livraison nous a permis de mettre en évidence le domaine et le temps d'utilisation du moteur électrique. Celui ci est amené à fonctionner en surcharge pendant des périodes de courtes durées et à faibles puissances pendant un temps important. Le modèle du moteur asynchrone exposé dans ce travail présente de ce fait des paramètres variables pour tenir compte des phénomènes de saturation magnétique, d'effet de peau dans le rotor et de l'élévation de température. Nous présentons les méthodes pour l'identification de ces paramètres à partir d'essais à vide et en charge du moteur. Les mesures sont effectuées sur un banc d'essai muni d'un onduleur à IGBT et d'une commande vectorielle. Le module de calcul développé autour du modèle identifié permet de calculer les grandeurs électriques et énergétiques en offrant plusieurs possibilités de fonctionnement. Ce module est ensuite intégré dans le logiciel de simulation de véhicules électriques et hybrides VERT de l'INRETS. L'utilisation de ce logiciel nous a permis d'examiner deux solutions à motorisation asynchrone. La première a concerné un véhicule urbain léger dont l'étude des performances et de consommation d'énergie nous ont permis de comparer les différentes stratégies de commandes et de vérifier l'importance de l'usage réel du véhicule. La deuxième a consisté en une chaine de traction à deux moteurs asynchrones pour un véhicule utilitaire de livraison en vue d'une économie d'énergie.
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Fredrik, Ljungberg. "Lane Change Intent Analysis for Preceding Vehicles : a Study Using Various Machine Learning Techniques." Thesis, Linköpings universitet, Reglerteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-139835.
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In recent years, the level of technology in heavy duty vehicles has increased significantly. Progress has been made towards autonomous driving, with increaseddriver comfort and safety, partly by use of advanced driver assistance systems (ADAS). In this thesis the possibilities to detect and predict lane changes for the preceding vehicle are studied. This important information will help to improve the decision-making for safety systems. Some suitable approaches to solving the problem are presented, along with an evaluation of their related accuracies. The modelling of human perceptions and actions is a challenging task. Several thousand kilometers of driving data was available, and a reasonable course of action was to let the system learn from this off-line. For the thesis it was therefore decided to review the possibility to utilize a branch within the area of artificial intelligence, called supervised learning. The study of driving intentions was formulatedas a binary classification problem. To distinguish between lane-change and lane-keep actions, four machine learning-techniques were evaluated, namely naive Bayes, artificial neural networks, support vector machines and Gaussian processes. As input to the classifiers, fused sensor signals from today commercially accessible systems in Scania vehicles were used. The project was carried out within the boundaries of a Master’s Thesis projectin collaboration between Linköping University and Scania CV AB. Scania CV AB is a leading manufacturer of heavy trucks, buses and coaches, alongside industrialand marine engines.
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Chi, Song. "Position-sensorless control of permanent magnet synchronous machines over wide speed range." Columbus, Ohio : Ohio State University, 2007. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1186974583.
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Norberg, Johan. "Large Scale Terrain Modelling for Autonomous Mining." Thesis, Linköpings universitet, Reglerteknik, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-57334.
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This thesis is concerned with development of a terrain model using Gaussian Processes to support the automation of open-pit mines. Information can be provided from a variety of sources including GPS, laser scans and manual surveys. The information is then fused together into a single representation of the terrain together with a measure of uncertainty of the estimated model. The model is also used to detect and label specific features in the terrain. In the context of mining, theses features are edges known as toes and crests. A combination of clustering and classification using supervised learning detects and labels these regions. Data gathered from production iron ore mines in Western Australia and a farm in Marulan outside Sydney is used to demonstrate and verify the ability of Gaussian Processes to estimate a model of the terrain. The estimated terrain model is then used for detecting features of interest.Results show that the Gaussian Process correctly estimates the terrain and uncertainties, and provide a good representation of the area. Toes and crests are also successfully identified and labelled.
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Bodin, Camilla. "Automatic Flight Maneuver Identification Using Machine Learning Methods." Thesis, Linköpings universitet, Reglerteknik, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-165844.
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This thesis proposes a general approach to solve the offline flight-maneuver identification problem using machine learning methods. The purpose of the study was to provide means for the aircraft professionals at the flight test and verification department of Saab Aeronautics to automate the procedure of analyzing flight test data. The suggested approach succeeded in generating binary classifiers and multiclass classifiers that identified six flight maneuvers of different complexity from real flight test data. The binary classifiers solved the problem of identifying one maneuver from flight test data at a time, while the multiclass classifiers solved the problem of identifying several maneuvers from flight test data simultaneously. To achieve these results, the difficulties that this time series classification problem entailed were simplified by using different strategies. One strategy was to develop a maneuver extraction algorithm that used handcrafted rules. Another strategy was to represent the time series data by statistical measures. There was also an issue of an imbalanced dataset, where one class far outweighed others in number of samples. This was solved by using a modified oversampling method on the dataset that was used for training. Logistic Regression, Support Vector Machines with both linear and nonlinear kernels, and Artifical Neural Networks were explored, where the hyperparameters for each machine learning algorithm were chosen during model estimation by 4-fold cross-validation and solving an optimization problem based on important performance metrics. A feature selection algorithm was also used during model estimation to evaluate how the performance changes depending on how many features were used. The machine learning models were then evaluated on test data consisting of 24 flight tests. The results given by the test data set showed that the simplifications done were reasonable, but the maneuver extraction algorithm could sometimes fail. Some maneuvers were easier to identify than others and the linear machine learning models resulted in a poor fit to the more complex classes. In conclusion, both binary classifiers and multiclass classifiers could be used to solve the flight maneuver identification problem, and solving a hyperparameter optimization problem boosted the performance of the finalized models. Nonlinear classifiers performed the best on average across all explored maneuvers.
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Kingravi, Hassan. "Reduced-set models for improving the training and execution speed of kernel methods." Diss., Georgia Institute of Technology, 2014. http://hdl.handle.net/1853/51799.
Full textAbstract:
This thesis aims to contribute to the area of kernel methods, which are a class of machine learning methods known for their wide applicability and state-of-the-art performance, but which suffer from high training and evaluation complexity. The work in this thesis utilizes the notion of reduced-set models to alleviate the
training and testing complexities of these methods in a unified manner. In the first part of the thesis, we use recent results in kernel smoothing and integral-operator learning to design a generic strategy to speed up various kernel methods. In Chapter 3, we present a method to speed up kernel PCA (KPCA), which is one of the fundamental kernel methods for manifold learning, by using reduced-set density estimates (RSDE) of the data. The proposed method induces an integral operator that is an approximation of the ideal integral operator associated to KPCA. It is shown that the error between the ideal and approximate integral operators is related to the error between the ideal and approximate kernel density estimates of the data. In Chapter 4, we derive similar approximation algorithms for Gaussian process regression, diffusion maps, and kernel embeddings of conditional distributions. In the second part of the thesis, we use reduced-set models for kernel methods to tackle online learning in model-reference adaptive control (MRAC). In Chapter 5, we relate the properties of the feature spaces induced by Mercer kernels to make a connection between persistency-of-excitation and the budgeted placement of kernels to minimize tracking and modeling error. In Chapter 6, we use a Gaussian process (GP) formulation of the modeling error to accommodate a larger class of errors, and design a reduced-set algorithm to learn a GP model of the modeling error. Proofs of stability for all the algorithms are presented, and simulation results on a challenging control problem validate the methods.
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Malik, Naveed ur Rehman. "Modelling, Analysis, and Control Aspects of a Rotating Power Electronic Brushless Doubly-Fed Induction Generator." Doctoral thesis, KTH, Elektrisk energiomvandling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-174349.
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This thesis deals with the modeling, analysis and control of a novel brushlessgenerator for wind power application. The generator is named as rotatingpower electronic brushless doubly-fed induction machine/generator (RPEBDFIM/G). A great advantage of the RPE-BDFIG is that the slip power recoveryis realized in a brushless manner. This is achieved by introducing an additionalmachine termed as exciter together with the rotating power electronicconverters, which are mounted on the shaft of a DFIG. It is shown that theexciter recovers the slip power in a mechanical manner, and delivers it backto the grid. As a result, slip rings and carbon brushes can be eliminated,increasing the robustness of the system, and reducing the maintenance costsand down-time of the turbine. To begin with, the dynamic model of the RPE-BDFIG is developed andanalyzed. Using the dynamic model, the working principle of the generatoris understood and its operation explained. The analysis is carried out atspeeds, ±20% around the synchronous speed of the generator. Moreover, thedynamics of the generator due to external load-torque disturbances are investigated.Additionally, the steady-state model is also derived and analyzed forthe machine, when operating in motor mode. As a next step, the closed-loop control of the generator is considered indetail. The power and speed control of the two machines of the generator andthe dc-link voltage control is designed using internal model control (IMC)principles. It is found that it is possible to maintain the stability of thegenerator against load-torque disturbances from the turbine and the exciter,at the same time maintain a constant dc-link voltage of the rotor converter.The closed-loop control is also implemented and the operation of the generatorwith the control theory is confirmed through experiments.In the third part of the thesis, the impact of grid faults on the behaviourof the generator is investigated. The operation of the generator and its responseis studied during symmetrical and unsymmetrical faults. An approachto successful ride through of the symmetrical faults is presented, using passiveresistive network (PRN). Moreover, in order to limit the electrical and mechanicaloscillations in the generator during unsymmetrical faults, the dualvector control (DVC) is implemented. It is found that DVC to a certain extentcan be used to safeguard the converter against large oscillations in rotorcurrents. Finally, for completeness of the thesis, a preliminary physical design ofthe rotating power electronic converter has been done in a finite elementsoftware called ANSYS. The thermal footprint and the cooling capability,with estimates of the heatsink and fan sizes, are presented. Besides, another variant of a rotating electronic induction machine whichis based on the Lindmark concept and operating in a single-fed mode is also investigated. It’s steady-state model is developed and verified through experiments.QC 20151006
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Vahedi, Abolfazl. "Modélisation et caractérisation des machines synchro-reluctantes saturées par des méthodes numériques." Vandoeuvre-les-Nancy, INPL, 1996. http://www.theses.fr/1996INPL074N.
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Le présent travail est consacré à la modélisation des machines synchro-reluctantes (MSR) en tenant compte de la saturation et de l'effet croisé. Parmi les méthodes utilisées pour la caractérisation des MSR, la méthode numérique est la mieux adaptée à l'optimisation, mais elle nécessite un grand nombre de calculs, lorsqu'on tient compte de la distribution réelle des ampères-conducteurs et de la géométrie réelle de la machine. Pour réduire le nombre de calculs, tout en préservant la géométrie, nous proposons une distribution équivalente qui à le même fondamental que la distribution réelle. Les résultats obtenus par la distribution équivalente concordent bien avec ceux obtenus par la distribution réelle, ce qui montre que le niveau de saturation est pratiquement imposé par le seul fondamental. Après avoir vérifié cette méthode, nous l'avons appliquée à la modélisation d'une MSR à deux pôles. Ce modèle est ensuite utilisé pour la commande de la machine. Le fait d'imposer au courant sur l'axe direct une valeur constante et élevée, rend l'effet croisé négligeable et permet de contrôler le couple électromagnétique dans cette machine exactement comme dans une machine non saturée
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Chapuis, Yves André. "Controle direct du couple d'une machine asynchrone par l'orientation de son flux statorique." Grenoble INPG, 1996. http://www.theses.fr/1996INPG0006.
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De part sa robustesse, la simplicité de sa structure, son poids et sa taille, la machine asynchrone offre de nouvelles perspectives technologiques dans de nombreux domaines industriels, où l'on apprécie principalement son peu de maintenance et son faible coût. Avec les progrès de l'électronique de puissance, liés à l'apparition de composants interrupteurs rapides, et le développement des technologies numériques de commande, câblées ou programmées, il est possible à présent, de choisir une structure de commande beaucoup plus évoluée. Ainsi, la commande vectorielle à flux rotorique orienté d'une machine à induction peut maintenant mettre en évidence des principes de contrôle du couple permettant d'obtenir des performances équivalentes à celles de la machine à courant continu. Cependant cette structure nécessite, en général, la mise en place de capteurs sur l'arbre pour la connaissance d'une grandeur mécanique. De plus elle reste très sensible aux variations de paramètres de la machine, notamment celles de la résistance rotorique. Le travail réalisé dans le cadre de cette thèse propose une alternative à ces problèmes de sensibilité. En effet, on présente ici une méthode dans laquelle les grandeurs de contrôle que sont le flux statorique et le couple électromagnétique, sont calculées à partir des seules grandeurs liées au stator et ceci sans l'intervention de capteurs mécaniques. Cette nouvelle structure de commande, couramment nommée : Contrôle Direct du Couple de la machine asynchrone (Direct Torque Control DTC), a été développée plus récemment. Pour l'étude de cette structure de commande, on a choisi de commencer par mettre en place, à partir des informations présentées dans les publications, un dispositif expérimental et un logiciel de simulation. Par la suite, on a développé et complété ces deux supports d'étude, en vue des travaux spécifiques que l'on s'est fixés. Pour thèse de ces travaux, on a décidé d'analyser les comportements de la commande dans une très large plage de vitesses. Pour cela, on s'est appuyé sur les conditions de fonctionnement d'applications précises, comme celles du véhicule électrique pour laquelle on a réalisé une étude complémentaire en simulation
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Nordfors, Per. "Prediction of Code Lifetime." Thesis, Linköpings universitet, Statistik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-135060.
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There are several previous studies in which machine learning algorithms are used to predict how fault-prone a piece of code is. This thesis takes on a slightly different approach by attempting to predict how long a piece of code will remain unmodified after being written (its “lifetime”). This is based on the hypothesis that frequently modified code is more likely to contain weaknesses, which may make lifetime predictions useful for code evaluation purposes. In this thesis, the predictions are made with machine learning algorithms which are trained on open source code examples from GitHub. Two different machine learning algorithms are used: the multilayer perceptron and the support vector machine. A piece of code is described by three groups of features: code contents, code properties obtained from static code analysis, and metadata from the version control system Git. In a series of experiments it is shown that the support vector machine is the best performing algorithm and that all three feature groups are useful for predicting lifetime. Both the multilayer perceptron and the support vector machine outperform a baseline prediction which always outputs the mean lifetime of the training set. This indicates that lifetime to some extent can be predicted based on information extracted from the code. However, lifetime prediction performance is shown to be highly dataset dependent with large error magnitudes.
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Ouriagli, Mohammed. "Contribution à la synthèse de commandes robustes pour machines synchrones à aimants permanents." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL136N.
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Le travail de mémoire porte sur la synthèse de commandes robustes pour machines synchrones à aimants permanents en tenant compte des amortisseurs et de variations de paramètres de la machine. Dans un premier temps, une commande basée sur le contrôle vectoriel et sur l'utilisation de correcteurs classiques de type proportionnel intégral a été élaborée. Le dimensionnement de ces correcteurs a été facilité par l'introduction d'un algorithme de découplage des courants statoriques direct et en quadrature. Dans un deuxième temps, nous nous sommes intéressé à la synthèse de commandes robustes et particulièrement, au contrôle H infini et à la commande par mode de glissement. Elles permettent la prise en compte des différentes perturbations et assurent en outre, un bon compromis robustesse/performances
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Carmona, Sanchez Jesus. "A smart adaptive load for power-frequency support applications." Thesis, University of Manchester, 2016. https://www.research.manchester.ac.uk/portal/en/theses/a-smart-adaptive-load-for-powerfrequency-support-applications(043dde9b-b753-4a6a-9c41-4c93b34681f9).html.
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At present, one of the main issues in electric power networks is the reduction in conventional generation and its replacement by low inertia renewable energy generation. The balance between generation and demand has a direct impact on the system frequency and system inertia limits the frequency rate of change until compensation action can be undertaken. Traditionally generation managed frequency. In future, loads may be required to do more than just be able to be switched off during severe under frequency events. This thesis focuses on the development and practical implementation of the control structure of a smart adaptive load for network power-frequency support applications. The control structure developed makes use of advanced demand side management of fan loads (powered by AC drives) used in heating, ventilation, and air conditioning systems; where a change in power at rated load has little effect on their speed due to the cubic relationship between speed and power. The AC drive implemented in this thesis is based on an induction motor and a two level voltage source converter. To achieve the smart adaptive load functionality, first a power-frequency multi-slope droop control structure (feedforward control) is developed; relating the frequency limits imposed by the network supplier and the fan power-speed profile (Chapter 2, Fig 2.19). Secondly, this control structure is combined with the control developed, in Chapter 3, for the AC drive powering the fan load. The full development of the control structure of the AC drive, its tuning process and its practical implementation is given; an equation is developed to find suitable tuning parameters for the speed control of the nonlinear load (fan load), i.e. Eq. (3.59).The analysis and simulation results provided in Chapter 4 conclude that a fast control of the active power drawn by the AC drive is possible by controlling the electromagnetic torque (hence current) of the induction motor without disturbing the fan load overly. To achieve this, changes between closed loop speed control and open loop torque control (power control) are performed when needed. Two main issues were addressed before the hardware implementation of the smart adaptive load: the estimation of the network frequency under distorted voltage conditions, and the recovery period of the network frequency. In this thesis two slew rate limiters were implemented to deal with such situations. Other possible solutions are also outlined. Finally, experimental results in Chapter 5 support results given in Chapter 4. A full power-frequency response is achieved by the smart adaptive load within 3s.
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Gaeta, Alberto. "Fault Tolerant Sensorless Permanent Magnet Synchronous Motor Drives." Doctoral thesis, Università di Catania, 2012. http://hdl.handle.net/10761/996.
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High cost and complexity of fault tolerant motor drives has relegated them to mission critical, no-compromise applications.
Heeding to this target application, past research efforts have been mainly focused on developing highly redundant, multiphase fault-tolerant solutions able to assure a very high fault tolerance level.
However, many other applications would benefit from the availability of solutions ensuring an acceptable level of fault tolerance.
The present work shows that, if tolerance is limited to few common faults and a reasonable performance penalty after a fault is accepted, a three-phase, voltage source inverter-fed, sensorless motor drive can be made fault tolerant by acting mainly on the control strategy, thus keeping to a minimum the required hardware modifications and additions.
After an initial classification of the possible faults which may affect three-phase VSI-fed drives, a fault detection and identification technique for converter faults is analyzed, able to ensure reduced response times. Therefore, modifications to a sensorless rotor position estimation technique are proposed in order to make a sensorless drive as fault tolerant as their sensored counterparts. Succesively, considering a PMSM motor with star center accessibility, two-phase sensorless operation is extensively studied and a new model is introduced maintaining the same control performance of a standard qd reference frame model. The new model is used for vector control of the machine either in sensored and sensorless conditions to confirm that advanced control of two-phase sensorless operation is the only post-fault strategy allowing the elimination of any redundant hardware.
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Queiroz, Francisco Canind? Holanda de. "Controle vetorial de velocidade de um motor de indu??o trif?sico com estima??o neural de fluxo." Universidade Federal do Rio Grande do Norte, 2008. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15193.
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This work describes the study and the implementation of the speed control for a three-phase induction motor of 1,1 kW and 4 poles using the neural rotor flux estimation. The vector speed control operates together with the winding currents controller of the stator phasis. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed controls to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The main DSP recources used by the system are, respectively, the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system
Este trabalho descreve o estudo e a implementa??o de um controle vetorial de velocidade para um motor de indu??o trif?sico de 1.1 kW / 4 p?los utilizando estima??o neural de fluxo do rotor. O controle vetorial de velocidade opera em conjunto com o controle das correntes nos enrolamentos de cada fase do estator. A estima??o neural de fluxo aplicada ao controle vetorial de velocidade tem como objetivo compensar a depend?ncia dos estimadores convencionais em rela??o ?s varia??es nos par?metros da m?quina devido a aumentos de temperatura ou satura??o magn?tica do rotor. O sistema de controle implementado possibilita uma compara??o direta dos respectivos desempenhos de velocidade sob orienta??o do estimador neural em rela??o ao estimador convencional de fluxo. Todo o controle do sistema ? realizado por um programa desenvolvido em linguagem padr?o ANSI C. Os principais recursos do DSP utilizados pelo sistema s?o, respectivamente, os canais de convers?o A/D, as sa?das PWM e as interfaces paralela e serial RS-232, as quais s?o respons?veis, respectivamente, pela programa??o do DSP e a captura de dados atrav?s de um sistema de supervis?o
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Pinto, Adriano Costa 1989. "Controle integrado de tensão e potência reativa através de aprendizado de máquina." [s.n.], 2015. http://repositorio.unicamp.br/jspui/handle/REPOSIP/259987.
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Orientador: Walmir de Freitas FilhoDissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação
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Resumo: A crescente demanda por energia elétrica, por vezes em ritmo mais acelerado que os investimentos em expansão das redes de distribuição, tem levado as distribuidoras a operarem próximo aos limites aceitáveis, o que torna toda a operação da rede mais complexa. Um dos desafios atuais é estabelecer um efetivo controle de tensão e potência reativa (Volt/var) na rede buscando melhorar o nível de operação e de eficiência energética da rede. Muitas propostas para encontrar a solução do problema partiram de uma abordagem de forma desacoplada: o controle de tensão e o controle de potência reativa foram resolvidos separadamente. Neste trabalho, porém, foram estudados métodos de solução do problema visando à segurança da operação e à otimização global dos recursos da rede de modo integrado, ou seja, considerando a dependência entre tensão e potência reativa. Na literatura, grande parte dos trabalhos reportam soluções baseadas em modelos elétricos da rede de distribuição. Os métodos estudados nessa dissertação são baseados em técnicas de aprendizado de máquina com o objetivo de construir um modelo capaz de utilizar apenas as medições de tensão e corrente provenientes dos medidores instalados ao longo da rede e obter o melhor despacho dos ajustes dos dispositivos de controle, sem a necessidade de um modelo elétrico do sistema. A grande vantagem de não depender dos dados e modelo elétrico do sistema está associada às imprecisões tipicamente existentes na base de dados elétricos das concessionárias de distribuição de energia elétrica. Neste contexto, primeiramente, propõe-se o uso de aprendizado por reforço, no qual o agente interage com a rede enquanto acumula experiência de operação dos controles. A implementação através do algoritmo Q-Learning permite a construção de um operador virtual da rede de distribuição a partir dos dados provenientes dos medidores instalados em determinadas barras do sistema, dos quais é extraído o estado corrente da condição de carregamento da rede. Os principais aspectos da aplicação do método ao problema de controle integrado de tensão e potência reativa são simulados em redes típicas e as capacidades de aplicação prática ao cenário atual do sistema elétrico são discutidas. Em uma segunda etapa, propõe-se utilizar um algoritmo de aprendizado supervisionado através de Máquinas de Vetores de Suporte (em inglês, Support Vector Machine ¿ SVM), uma técnica eficientemente aplicada a problemas de mineração de dados. O modelo é implementado através de técnicas de classificação, que extraem características relevantes nos conjuntos de dados, a fim de otimizar a operação da rede para cada condição de carregamento, eliminando a necessidade de repetir o treinamento do modelo ou calcular uma nova solução do problema de otimização a cada novo cenário. Discute-se o desempenho do método baseado em SVM para diferentes características de entrada. Investiga-se ainda a generalização do modelo proposto na presença de ruídos nos dados e no caso de reconfiguração da rede. Estudos em sistemas típicos de distribuição mostram que o método proposto é eficiente na solução de problemas práticos do dia-a-dia das concessionárias, principalmente em ambientes com grande volume de dados
Abstract: The growing demand for electricity, sometimes at a faster rate than investments in distribution network expansion, has led utilities operating close to acceptable limits, which makes the network operation more complex. One of current challenges is to establish an effective voltage and reactive power control, improving the operation as well as the efficiency of the distribution network. There are many methods reported to find a solutions for the voltage and reactive power problem. Most of them have adopted a decoupled form, solving the voltage control and reactive power (Volt/var) control separately. However, in this work, methods for the problem solution aiming the operation safety and the global assets optimization are approached in an integrated fashion, i. e., considering the dependence between voltage and reactive power. Most papers reports solution based on electrical models of distribution network. In this dissertation, the methods studied are based on machine learning techniques aiming to build a model with directly power meter data using capability, and set optimal dispatch of controls devices adjustments, without the need of an electrical model of the system and, therefore, not susceptible to inaccuracies of the model of the distribution network under study. Firstly, it proposes a reinforcement learning use, in which the agent interacts with the network while earns control operating experience. The implementation, thought de Q-Learning algorithm allows a construction of a distribution network virtual operation from data obtained from the meters installed on buses. From the meter data, is extracted the current state of the network loading condition. The main aspects of the application of the method to the integrated voltage and reactive power control are simulated in a typical network and the possibilities of practical application in the current scenario of the electrical system are discussed. In a second step, an algorithm for supervised learning via the Support Vector Machine (SVM), a technique applied efficiently to problems in data mining is proposed. The model is implemented by classification techniques, extracting relevant features in the data sets from the power meters in order to optimize the operation of the network for each loading condition. Thus it eliminates the need to retraining model or calculating a new optimization problem solution for each new scenario. Discusses the performance based on different features for SVM model input. Also the generalization capabilities of the proposed model in the presence of noise and in the case of network reconfiguration are studied. Studies in typical distribution systems show that proposed method is a good candidate to solve the practical problem of the system, especially in large networks with large amounts of data
Mestrado
Energia Eletrica
Mestre em Engenharia Elétrica
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Payn, Martin. "Flux vector control of asynchronous machines." Thesis, University of Surrey, 1991. http://epubs.surrey.ac.uk/844608/.
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The present work introduces the dynamic induction machine model using the concept of space vector notation, and shows the fundamentals of torque production to be related to the current and flux space vector interaction. By theoretical analysis the transient response of the current and voltage fed machine is determined in terms of the machine eigenvalues, and this is confirmed using simulation techniques. The concept of torque control using the current and flux space vectors' magnitude and phase is introduced. It is shown that maintaining the flux space vector's magnitude constant is a sensible approach and that transient free torque responses are possible by controlling the current space vector magnitude and phase with respect to the flux space vector, which is termed vector control. Previously only magnitude control was realised, and this is termed scalar control. It is shown that the simplest practical vector controllers work in the rotating rotor flux space vector reference frame, generated from a dynamic machine model using current and speed/position measurements from the real machine. The major disadvantage of the parameter sensitivity of this approach is examined. To complement the theoretical analysis a practical vector controller was to be built. This was designed around a new DSP micro-controller (TMS320C14) and featured a 10 kHz sampling rate. A fully instrumented 7.5 kW test rig was also developed with the induction machine driven from a modified 1 kHz inverter. The measurement of high performance shaft torque is investigated, to allow comparisons between the theoretical and practical results. The practical work centred on the comparison of the dynamic machine model with measurements made on the real machine (torque and flux) and with the theory. These showed excellent steady state performance but the dynamic response was disappointing. The implications of the model not representing the real machine transiently are investigated.
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Arab, Khaburi Davood. "Contribution à la commande vectorielle des machines synchrones à aimants permanents sans utilisation des capteurs mécaniques." Vandoeuvre-les-Nancy, INPL, 1998. http://www.theses.fr/1998INPL125N.
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Ce mémoire est consacré à la commande vectorielle des machines synchrones à aimants permanents, et pour une grande part aux problèmes liés à la détection de la position du rotor. Dans la première partie nous présentons une méthode originale et économique d'obtention directe des fonctions trigonométriques de la position rotorique, qui utilise un résolveur et ne nécessite aucun circuit intégré spécialisé. La deuxième partie concerne l'identification en ligne des paramètres des machines synchrones à aimants permanents : celle-ci permet en particulier d'améliorer les performances de l'estimateur de la position du rotor, qui dépendent fortement de la précision des paramètres du modèle de la machine. Enfin la troisième partie est consacrée à la commande vectorielle sans capteur mécanique. Considérant que la composante directe de la f. E. M. A une valeur nulle, nous en déduisons une méthode de correction des valeurs estimées de la position et de la vitesse du rotor.
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Paiva, Jos? Alvaro de. "Controle vetorial de velocidade de uma m?quina de indu??o sem mancais trif?sica com bobinado dividido utilizando estima??o neural de fluxo." Universidade Federal do Rio Grande do Norte, 2007. http://repositorio.ufrn.br:8080/jspui/handle/123456789/15115.
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Previous issue date: 2007-12-07Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico
This work describes the study and the implementation of the vector speed control for a three-phase Bearingless induction machine with divided winding of 4 poles and 1,1 kW using the neural rotor flux estimation. The vector speed control operates together with the radial positioning controllers and with the winding currents controllers of the stator phases. For the radial positioning, the forces controlled by the internal machine magnetic fields are used. For the radial forces optimization , a special rotor winding with independent circuits which allows a low rotational torque influence was used. The neural flux estimation applied to the vector speed controls has the objective of compensating the parameter dependences of the conventional estimators in relation to the parameter machine s variations due to the temperature increases or due to the rotor magnetic saturation. The implemented control system allows a direct comparison between the respective responses of the speed and radial positioning controllers to the machine oriented by the neural rotor flux estimator in relation to the conventional flux estimator. All the system control is executed by a program developed in the ANSI C language. The DSP resources used by the system are: the Analog/Digital channels converters, the PWM outputs and the parallel and RS-232 serial interfaces, which are responsible, respectively, by the DSP programming and the data capture through the supervisory system
Este trabalho descreve o estudo e a implementa??o do controle vetorial de velocidade de uma m?quina de indu??o sem mancais trif?sica com bobinado dividido de 4 p?los e 1.1kW utilizando estima??o neural de fluxo do rotor. O controle vetorial de velocidade opera em conjunto com os controles de posicionamento radial e das correntes nos enrolamentos de cada fase do estator. Para o posicionamento radial utilizam-se as for?as controladas pelos campos magn?ticos no interior da m?quina. Para a otimiza??o das for?as radiais operando com influ?ncia m?nima do torque rotacional, foi utilizado um modelo especial de bobinado do rotor com circuitos independentes. A estima??o neural de fluxo aplicada ao controle vetorial de velocidade tem o objetivo de compensar a depend?ncia dos estimadores convencionais em rela??o ?s varia??es nos par?metros da m?quina devido a aumentos de temperatura ou satura??o magn?tica do rotor. O sistema de controle implementado possibilita uma compara??o direta dos respectivos desempenhos de velocidade e posi??o radial da m?quina sob orienta??o do estimador neural em rela??o ao estimador convencional de fluxo. Todo o controle do sistema ? realizado por um programa desenvolvido em linguagem padr?o ANSI C. Os recursos do DSP utilizados pelo sistema s?o: os canais de convers?o A/D, as sa?das PWM e as interfaces paralela e serial RS-232, as quais s?o respons?veis, respectivamente, pela programa??o do DSP e a captura de dados atrav?s de um sistema de supervis?o
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Wade, Scott. "Parameter identification for vector controlled induction machines." Thesis, Heriot-Watt University, 1995. http://hdl.handle.net/10399/1311.
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Faidallah, Amer. "Contribution à l'identification et à la commande vectorielle des machines asynchrones." Vandoeuvre-les-Nancy, INPL, 1995. http://www.theses.fr/1995INPL014N.
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Aujourd’hui la machine asynchrone gagne beaucoup de terrain dans les applications nécessitant la commande de vitesse, de couple ou de position. Ce mémoire apporte une contribution à l'identification des paramètres de ce type de machine et à l'amélioration de sa commande vectorielle. La première partie concerne des procédés d'identification des paramètres de la machine avec des moyens informatiques à la fois modernes et performants. Afin de découpler la commande de flux de celle du couple, une orientation du flux statorique, rotorique ou magnétisant est nécessaire. Après analyse c'est l'orientation du flux rotorique qui a été retenue. Le découplage des commandes et des courants isd et isq n'étant pas facile à assurer dans le cas d'une alimentation en tension: un bloc de calcul, placé en aval des régulateurs des courants est proposé pour résoudre ce problème. Les échauffements des conducteurs dans la machine, la saturation des circuits magnétiques peuvent dégrader la commande vectorielle, qu'elle soit de type directe ou indirecte. Des solutions sont proposées et des simulations sont faites pour en tester les performances. Ajoutée aux problèmes décrits, l'influence des paramètres se fait tout particulièrement sentir dans le cas d'une commande sans capteur de vitesse. Une méthode est proposée pour minimiser cette influence sur l'estimateur de vitesse. Un banc expérimental a été réalisé. Il permet d'effectuer toutes les études expérimentales sans une intervention matérielle quand on veut passer d'une stratégie à une autre
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Bala, Mokrane. "Contributions à l'amélioration de la loi de commande d'une machine électrique d'un compresseur de climatisation : réduction du nombre de capteurs de courant." Thesis, université Paris-Saclay, 2021. http://www.theses.fr/2021UPAST014.
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Ces travaux de thèse s’inscrivent dans le cadre du projet EDC (Electrical Driven Compressor), qui vise à développer des compresseurs de climatisation électriques fiables, compacts, conformes aux normes automobiles et à faible coût de production. Cette thèse est composée de deux parties. La première partie est consacrée à la suppression des capteurs de courants de phase et à leur remplacement par un seul capteur de courant au niveau du bus continu. Cette suppression a été accompagnée du développement d'un algorithme de reconstruction des courants de phase. La modification de la loi de commande SVPWM par un algorithme analytique a été rendue nécessaire afin d'assurer la reconstruction des courants de phase sur toute la plage de fonctionnement. Des résultats de simulation et d’expérimentation ont montré le bon fonctionnement de l’algorithme de reconstruction des courants de phase en utilisant la SVPWM modifiée. La deuxième partie de ce travail a consisté à réduire les interférences électromagnétiques via la commande, en utilisant des techniques d’étalement spectral basée sur la PWM aléatoire. La complexité de cette partie a principalement concerné l'adaptation de cette méthode à notre algorithme de reconstruction basé sur la SVPWM modifiée. Les résultats de simulation et les résultats expérimentaux ont montré un bon étalement spectral des différentes harmoniques des courants de phase et des tensions de sortie de l’onduleurThis thesis work is part of the EDC (Electrical Driven Compressor) project, which aims to develop reliable, compact electric air conditioning compressors that comply with automotive standards and have low production costs. This thesis is made up of two parts. The first one is devoted to the elimination of phase current sensors and their replacement by a single current sensor at the DC bus level. This removal was performed with the help of an algorithm for the reconstruction of phase currents. The modification of the SVPWM control law by an analytical algorithm was made necessary in order to ensure the reconstruction of the phase currents over the entire operating range. Simulation and experimentation results have shown the good working of the phase current reconstruction algorithm using the modified SVPWM. The aim of the second part of this work was to reduce electromagnetic interference by control, using spread spectral techniques based on random PWM. The complexity of this part mainly concerned the adaptation of this method to our reconstruction algorithm based on the modified SVPWM. The simulation results and the experimental results showed good spectral spreading of the different harmonics of the phase currents and the output voltages of the inverter
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Hrnčárek, Martin. "Moderní struktury řízení servosystémů se střídavými pohony." Master's thesis, Vysoké učení technické v Brně. Fakulta elektrotechniky a komunikačních technologií, 2010. http://www.nusl.cz/ntk/nusl-218311.
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This master thesis deals with the modern algorithms of the asynchronous induction machine and permanent magnet induction machine. It focuses at vector control, direct torque control and input-output feedback linearization. It also describes a library creation and its usages in the Matlab – Simulink environment. The final part of this thesis contains an implementation of chosen algorithms on the DSC Freescale 56F800E family.
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Ghennam, Tarak. "Supervision d’une ferme éolienne pour son intégration dans la gestion d’un réseau électrique, Apports des convertisseurs multi niveaux au réglage des éoliennes à base de machine asynchrone à double alimentation." Thesis, Ecole centrale de Lille, 2011. http://www.theses.fr/2011ECLI0012/document.
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La première thématique développée dans ce mémoire vise à développer de nouveaux algorithmes pour la commande des éoliennes reposant sur une machine asynchrone à double alimentation et des convertisseurs multi niveaux. Deux stratégies de contrôle direct du courant, basées sur l’Hystérésis à Zones Carrées et l’Hystérésis à Zones Circulaires (HZCi) ont été proposées. Celles-ci consistent à appliquer des vecteurs de tension appropriés pour contrôler les puissances actives et réactive générées et permettent également d’équilibrer les tensions du bus continu interne des convertisseurs. Des résultats de simulation et d’expérimentation montrent que la stratégie basée sur l’HZCi est meilleure en termes de forme d’onde et de contenu harmonique des tensions de sortie.La seconde concerne la supervision et la gestion des puissances active et réactive dans une ferme éolienne au vu de son intégration dans un réseau électrique. Cette supervision centralisée est assurée par un algorithme qui distribue les consignes de puissance aux éoliennes de la ferme de manière proportionnelle. Ces références sont fonction de la capacité maximale de production de l’éolienne. Pour cela, une analyse des transits de puissance dans le système éolien à base de la machine asynchrone à double alimentation a été effectuée. Elle a permis de déterminer la caractéristique (P, Q) du générateur et de calculer ses limites de compensation en termes de puissance réactive. Une gestion locale des puissances de chaque éolienne a été développée permettant ainsi une répartition des puissances entre le stator de la machine et le convertisseur coté réseau en considérant plusieurs modes de fonctionnement du système éolienThis research work deals with two topics conditioning the large scale development of wind turbines into electrical grids. The first is devoted to the development of new algorithms for the control of Doubly Fed Induction Machine (DFIM) based wind energy conversion systems. Two direct current control strategies have been proposed and are based on the hysteresis square areas (HZCA) and hysteresis circular areas (HZCI). Both strategies apply an appropriate voltage vector to control the active and reactive powers delivered to the grid, and also, to balance the voltages of the inner DC bus converter. Simulation and experimental results show that the HZCI strategy is better than HZCA in terms of output voltage waveforms and harmonic contain.The second topic is dedicated to the active and reactive powers supervision in a wind farm in order to supply prescribed power references from the grid operator. This supervision is ensured by a centralized algorithm that distributes power references between wind turbines in a proportional way. These references are calculated according to the maximum production capacity of wind turbines. An analysis of the power flow in the DFIM based wind energy system has been made to identify the (P, Q) characteristic and to calculate limits in terms of reactive power compensation. The local power management of each wind system has been developed allowing the powers distribution between the stator of the DFIM and the grid side converter by considering several operating modes of the wind generator
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Pahkasalo, Carolina, and André Sollander. "Adaptive Energy Management Strategies for Series Hybrid Electric Wheel Loaders." Thesis, Linköpings universitet, Fordonssystem, 2020. http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-166284.
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An emerging technology is the hybridization of wheel loaders. Since wheel loaders commonly operate in repetitive cycles it should be possible to use this information to develop an efficient energy management strategy that decreases fuel consumption. The purpose of this thesis is to evaluate if and how this can be done in a real-time online application. The strategy that is developed is based on pattern recognition and Equivalent Consumption Minimization Strategy (ECMS), which together is called Adaptive ECMS (A-ECMS). Pattern recognition uses information about the repetitive cycles and predicts the operating cycle, which can be done with Neural Network or Rule-Based methods. The prediction is then used in ECMS to compute the optimal power distribution of fuel and battery power. For a robust system it is important with stability implementations in ECMS to protect the machine, which can be done by adjusting the cost function that is minimized. The result from these implementations in a quasistatic simulation environment is an improvement in fuel consumption by 7.59 % compared to not utilizing the battery at all.
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Stival, Luiz Henrique Reis de Castilho. "Proposição de uma plataforma de acionamento do motor de indução monofásico para aplicação em lavadora de roupa." Universidade do Estado de Santa Catarina, 2010. http://tede.udesc.br/handle/handle/1905.
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Previous issue date: 2010-08-20Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
The single-phase induction motor, in permanent split capacitor topology, is utilized on most of the clothes wash machines on Brazilian market. This configuration presents limitations on motor drive and on energy efficiency of the system. This work suggests a drive control method for the single-phase induction motor, aiming to deliver benefits on energy efficiency and improving motor drive. On this work, a mathematical model of the motor is derived to compare, through simulation, this proposal among different solutions. Then, the implementation of the proposal is done to gather experimental results. These results are compared to the results of the current control used on wash machines. The proposal achieved good advantages on dynamics response and system efficiency, although impacts the final cost of the solution.
O motor de indução monofásico, em sua topologia de capacitor permanente, é empregado na maioria das lavadoras de roupas do mercado nacional. Esta configuração apresenta limitações no acionamento do motor, e oferece uma limitada eficiência energética do sistema. Este trabalho propõe um método de controle do motor de indução monofásico que visa oferecer benefícios em termos da eficiência energética e melhoria do acionamento do motor quando utilizado em lavadoras de roupa. No trabalho, é levantado um modelo matemático do motor para que, através de simulação, possa ser realizado um estudo comparativo da solução proposta com outras soluções. Em seguida, se dá a implementação da proposta para obtenção de resultados práticos. Estes resultados são então comparados aos resultados do controle original utilizado em lavadoras de roupa. São alcançados benefícios na dinâmica e eficiência do sistema, porém com um impacto no custo final da solução.
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Staines, Cyril Spiteri. "Sensorless position estimation in asymmetric induction machines." Thesis, University of Nottingham, 1998. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.267588.
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Lamine, Adoum. "Vector control of induction machines considering the stray load losses." Thesis, Liverpool John Moores University, 2006. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.436561.
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Afsharnia, Saeed. "Contrôle vectoriel des machines synchrones à aimants permanents : identification des paramètres et minimisation des ondulations de couple." Vandoeuvre-les-Nancy, INPL, 1995. http://docnum.univ-lorraine.fr/public/INPL_T_1995_AFSHARNIA_S.pdf.
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Le présent travail apporte des solutions aux problèmes que pose le contrôle du couple des machines synchrones à aimants permanents alimentées par un onduleur triphasé. La première contribution concerne l'identification en ligne des constantes de temps électriques des machines synchrones à répartition sinusoïdales des conducteurs: celle-ci améliore l'efficacité de l'algorithme de découplage du contrôle des courants direct et en quadrature et permet d'imposer des courants optimaux même en régime transitoire. La seconde partie traite des machines synchrones à rotor lisse et à répartition non sinusoïdale des conducteurs, dans lesquelles on annule les ondulations du couple par une modulation appropriée des courants. Une méthode simple et efficace consiste à annuler le courant direct et à imposer un courant en quadrature inversement proportionnel à la F. E. M. Correspondante. Enfin une troisième partie est consacrée à l'autopilotage des machines synchrones à aimants sans capteur de position mécanique. Cet autopilotage est effectué simplement à partir des grandeurs externes de la machine en utilisant le fait que la composante directe de la F. E. M. Induite est nulle
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Holliday, Derrick Michael John. "On-line tests for parameter identification in cage induction machines." Thesis, Heriot-Watt University, 1994. http://hdl.handle.net/10399/1344.
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