Brushless permanent magnet (PM) drive systems offer a high efficiency over a wide power/torque-speed operating envelope, however, there are a number of problems that may limit, or complicate, their operation particularly in automotive and aerospace vehicular applications, i.e. the loss of control of the power silicon gate drive circuitry during fluxweakening operation, control of high-speed low-inductance machines and the presence of large electrolytic capacitors on the inverter DC link. Current Source Inverters (CSIs) could potentially address some or all of the above issues. However, they have found little application to date due to the wide use of the Voltage Source Inverter (VSI) circuit topology.This thesis investigates feasibility of utilising Current Source Inverters (CSIs) to control permanent magnet synchronous machines in automotive and aerospace actuation systems. CSIs, switching at the fundamental frequency, were used in some of the first semiconductor based, electronic variable speed drive systems that utilised the simple, low maintenance AC induction motor. However, the rapid progress of semiconductors and discovery of Pulse Width Modulation (PWM) techniques soon resulted in the Voltage Source Inverter (VSI) replacing the CSI in all but the highest power applications. Modern power electronics and (micro-processor based) control systems mean that the advantages of VSI systems may no longer be significant and combined with the unique environmental conditions that automotive and aerospace applications present, could allow the CSI to offer advantages over VSIs in these applications.The thesis presents the switching and control logic for CSIs and mapping to the more conventional VSI logic. Analysis is made of the various loss mechanisms in VSI and CSI power circuitary. Simulation models of the VSI and CSI structures are presented and representative drive systems designed, built and tested to validate the model developed. Comparisons are made of the two inverter topologies based on power conversions and loss audits of the test validation hardware.

No description available.

CoordenaÃÃo de AperfeÃoamento de Pessoal de NÃvel Superior / O Motor de RelutÃncia VariÃvel (MRV) vem cada vez mais chamando a atenÃÃo da indÃstria e da comunidade acadÃmica. Isso se deve ao crescente desenvolvimento da eletrÃnica de potÃncia e na Ãrea de microprocessadores nos Ãltimos anos, o que permitiu o avanÃo de outros sistemas de acionamentos tais como com MRV. A competitividade do MRV se justifica por seu baixo custo de produÃÃo e manutenÃÃo, uma elevada densidade de potÃncia, robustez e resistÃncia a faltas. O presente trabalho propÃe um esquema de controle robusto baseado em um Controlador Preditivo Generalizado (GPC) pertencente a famÃlia de Controladores Preditivos Baseados em Modelo (MPC) aplicados a malha de corrente e velocidade de um sistema de acionamento com MRV. O controlador proposto, assim como controladores tradicionais aplicados neste tipo de sistema tais como o controlador por Histerese e o controlador PID sÃo tambÃm aplicados com o objetivo de proporcionar meios de comparaÃÃo dos resultados experimentais obtidos. A estrutura do controlador à baseada no projeto de um filtro de modo a permitir uma resposta rÃpida, rejeiÃÃo a distÃrbios, atenuaÃÃo de ruÃdos e robustez com um baixo custo computacional. O controlador proposto foi implementado e os resultados comparados com controladores tradicionais e analisados quantitativamente por meio de Ãndices de desempenho. Para execuÃÃo das rotinas de controle foi utilizado um DSP das Texas Instruments (TMS320F28335), sendo suas caracterÃsticas principais apontadas. O algoritmo do software de controle à esquematizado. O trabalho fez uso da bancada de pesquisa em MRV do laboratÃrio do Grupo de Pesquisa em AutomaÃÃo e RobÃtica (GPAR) da Universidade Federal do Cearà (UFC).

Рассмотрены различные способы измерений скорости ветра на различной высоте в нижних слоях атмосферы. Предложена новая конструкция радара для неконтактного измерения скорости ветра. В качестве излучателя антенной решетки предложено использовать трехэлементную вибраторную антенну. Выполнено электродинамическое моделирование антенной решетки. Предложена антенная решетка, формирующая 5 лучей шириной 7 градусов. Рассмотрена треугольная и квадратная сетка размещения элементов. Доказано преимущество антенной решетки с треугольной сеткой. Рассмотрено влияние амплитудного распределения мощности по элементам антенной решетки на диаграмму направленности. Исследовано влияние кластеризации решетки по 4 и 7 элементов. Доказано преимущество 4-х элементных кластеров. Исследовано влияние дискрета фазирования на характеристики антенны. Предложена 4-битовая схема фазовращателей. Схема управления фазовращателями оптимизирована на минимум управляющего тока. Определена дальность действия предложенного радара. / Various methods of wind speed measuring at different heights in the lower atmosphere are considered. A new scheme for constructing a radar for non-contact measurement of wind speed is proposed. A three-element dipole antenna is proposed as the radar antenna array element. The antenna array electrodynamic modeling is performed. The antenna array forming 5 beams with a width of 7 degrees are suggested. The square and triangular grid of elements placement in the antenna array is considered. The advantages of the antenna array with the triangular grid are justified. The influence of the amplitude distribution of radiated power in the antenna array on the radiation pattern is studied. The effect of clustering of the antenna array on its radiation is studied. 4- and 7-element clusters are considered. The advantage of 4-element clusters is proved. The effect of phasing discretization on the antenna characteristics is investigated. The 4-bit phase shifter scheme is proposed. The phase shifter control scheme is optimized for a minimum of the control current. The radar monitoring range is defined.

The diploma thesis is a part of the project Intelligent double arm juggling machine. The project is divided into two diploma thesis. This thesis deals with the motion control of juggling arms. Information about hardware and software resources used in this project is in the first part of thesis. There is explanation of the control loop, explanation of used communication protocols and implementation of program proceeding in the second part of thesis.