No description available.

Typescript (photocopy). / Digitized by Kansas Correctional Industries

The equivalent impedance of a RF plasma was experimentally determined by monitoring the voltage and current waveform for different input powers in real time. Average ion energies and fluxes were determined by a computer model which takes ion collisions in the sheath regions into account. In addition two models were proposed which explain how RF energy is converted to DC potential energy in the sheath. Etch rates of Si in a CF₄ discharge were also evaluated and related to the measurements.

Thesis (Masters Diploma (Electrical Engineering)) --Cape Technikon, Cape Town, 1987 / This thesis describes the development of a computerized Load Recorder. The load recorder is used by the Cape Town City Council to assist in the tariff investigation of electricity consumers. This investigation assists the consumers in selecting the best cost effective electricity tariff. It also motivates the consumers to maintain a constant load which in turn assists the Council in supplying the required electricity. The load recorder replaces a manual and time consuming method used in conducting the tariff investigation. The development of the load recorder involved the design of hardware and software. It was designed in a compact enclosure to hook up to the electricity meters of the consumer for a period of 7 days. The software was designed in the 6805 assembly language to log data and record the electricity load every 15 or 30 minutes for this period. At the end of this period the data is downloaded into the HP85 personal computer. A basic program was designed for the HP85 to analyse and compute the downloaded data. A graphical representation and analysis is printed by the HP85 computer. The given graph of the results represents the electricity used for this period. The tariff rates are analysed and calculated to determine the best cost effective tariff. A CMOS micro computer intergrated circuit was chosen due to the determined specification of the load recorder. In order to make the development of the load recorder possible an aid (tool) had to be designed and built for the chosen microprocessor. This development aid, the emulator, is included as part of this thesis. The Motorola exorciser only supported a cross assembler for the chosen microprocessor family. The emulator was designed and built to enable testing and debugging on the Exorciser. The development on the emulator involved a detailed analysis of the Exorciser development system. The emulator was designed using hardware and software. The hardware emulator board was designed as a standard Motorola size card which plugs into the Exorciser. The software was designed for the 6809 exorciser and for the 6805 emulator. The emulator was soak tested and debugged during the development of the load recorder. The emulator opened further avenues for future microcomputer design projects especially where a confined area and compactness is an important factor. The design and development of the emulator and the load recorder was conducted in the Computer Section of the City Electrical Engineer's Department of Cape Town.

Orientador: Walmir de Freitas Filho / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia Elétrica e de Computação / Made available in DSpace on 2018-08-27T18:46:05Z (GMT). No. of bitstreams: 1 Ricciardi_TiagoRodarte_D.pdf: 6633244 bytes, checksum: bcb56f82b62350db77ed247ac2913cc9 (MD5) Previous issue date: 2015 / Resumo: Modelos matemáticos e computacionais precisos dos diversos componentes de um sistema de energia elétrica são importantes para estudos e simulações em um cenário de planejamento e operação da rede elétrica. Dentre os elementos de um sistema de geração, transmissão e distribuição de energia elétrica, as cargas são as que apresentam maiores dificuldades em serem adequadamente representadas. Embora esse tema de pesquisa tenha sido exaustivamente explorado, a modelagem de carga tem recebido renovada atenção do setor produtivo e da academia por uma série de fatores, dentre os quais podemos destacar a proliferação de medidores eletrônicos, o interesse por modelos de novos equipamentos e a necessidade da representação mais fiel do comportamento de diferentes cargas frente a distúrbios no sistema. Esta tese de doutoramento propõe duas contribuições na linha de pesquisa sobre modelagem de carga em sistemas de energia elétrica. A primeira delas trata-se de um método de modelagem de carga baseado em medições e na detecção de distúrbios naturais de tensão. O procedimento proposto emprega medidores eletrônicos simples, que são instalados junto a instalações em sistemas de distribuição com motivo outro que não o de modelagem de carga. A ideia principal é a de utilizar tais medidores para, paralelamente a função que desempenham, fornecer para a concessionária informações sobre modelos de carga, como um subproduto da função principal que desempenham. A segunda contribuição proposta é na linha da modelagem de carga baseada em templates, uma técnica recentemente proposta na literatura para modelagem dinâmica de cargas industriais de grande porte. Nesta tese é proposto um modelo dinâmico simplificado de motores de velocidade variável controlados via conversores eletrônicos (Variable Frequency Drives ¿ VFDs), o qual é baseado em um modelo modificado de um motor de indução. O modelo proposto é adequado ao contexto da estrutura de modelagem de cargas industriais proposta pela técnica de modelagem baseada em templates e pode ser facilmente agregado e analisado em programas de simulação por parte de usuários sem necessidades de alterações do código fonte / Abstract: Accurate mathematical and computational models from various electric power systems components are important in a scenario of power systems studies and simulations for grid planning and operation. Among the elements in the electricity generation, transmission and distribution systems, the loads are probably the most difficult ones to be accordingly represented. Though this research topic has been exhaustively explored, there is a renewed interest in industry and academia for power systems load modeling, due to several reasons, including the proliferation of smart meters, the appearance of non-conventional types of load and the continuing need for even more confident representation of different load response for system disturbances. This Ph.D. thesis proposes two contributions to power systems load modeling research field. The first one deals with a load modeling method based on measurements and the detection of natural voltage disturbances. The proposed scheme uses simple smart meters, installed close to customers with a main goal other than load modeling. The main idea is to use data provided by those meters to, in parallel to the main function performed by this device, provide to the utility information regarding load models, as a byproduct capable to add value to the investment in this meters. The second contribution is in the template based load modeling, a recently methodology proposed for dynamic modeling of large industrial facilities. In this thesis, a simplified Variable Frequency Drive (VFD) dynamic model is proposed, which one is based on a modified induction machine model. The proposed model is suitable to the dynamic load model structure proposed by the template based methodology and can be easily aggregated and analyzed in simulation software by basic users without the need of programming a complex model / Doutorado / Energia Eletrica / Doutor em Engenharia Elétrica