The design of an active-unity power factor correction circuit with variable-hysteresis control for off-line dc-to-dc switching power supplies is described. Design equations relating the boost inductor current ripple to the circuit components selection and circuit performance arc discussed. A computer-aided design program (CADO) is developed to give the optimal circuit components selection. A 500 watt, 300 volt experimental circuit is built to verify the simulation and analysis results. The control-to-output response of the power factor circuit is verified with the experimental results. Design guidelines for the low-frequency feedback network are presented. Small-signal closed-loop responses are measured with an experimental power factor circuit. / Master of Science

<p>Multiple causes of continuously occurring power outages in Yazd Province of Iran have been experienced in recent years. This research studies how key stakeholders have perceived the results of the strategic decisions taken by directors of HEPP to diminish the power shortages and to even increase power supply to a limit of exporting power to other neighboring provinces. How could HEPP emerge from an organization in the edge of bankruptcy to an organization that can surpass all expectations and won over their competitors? HEPP’s strategic decisions followed implications of several models and finally a strategic plan on the bases of the Bryson model was selected and practically applied to achieve their final expected results. The literature review in this study describes selected models as well as the Bryson model set up and structure. This study portrays a demonstration and an evaluation of various strategic plan management models used in Iranian organization in particular HEPP. The researcher designed several questionnaires and forwarded them to HEPP’s administrators, employees and other stakeholders in three groups. Additional phone interviews were conducted and the quantitative as well as qualitative data collected was evaluated and displayed in tables and figures in this study. Data analysis demonstrates a few shortcomings, weaknesses and strengths that are discussed in detail and conclusive proposals are presented through the conclusion section in enhancement of HEPP’s services to the advantages of stakeholders and employees of HEPP with a complete consideration for HEPP’s well being and awareness of its competitors. Although this study is limited in scope it highlights what needs to be done in HEPP or similar hydro electric organizations in Iran, and it can act as a stepping stone for further research and analysis of hydro electrical demand and supply issues in Yazd region of Iran.</p>

Multiple causes of continuously occurring power outages in Yazd Province of Iran have been experienced in recent years. This research studies how key stakeholders have perceived the results of the strategic decisions taken by directors of HEPP to diminish the power shortages and to even increase power supply to a limit of exporting power to other neighboring provinces. How could HEPP emerge from an organization in the edge of bankruptcy to an organization that can surpass all expectations and won over their competitors? HEPP’s strategic decisions followed implications of several models and finally a strategic plan on the bases of the Bryson model was selected and practically applied to achieve their final expected results. The literature review in this study describes selected models as well as the Bryson model set up and structure. This study portrays a demonstration and an evaluation of various strategic plan management models used in Iranian organization in particular HEPP. The researcher designed several questionnaires and forwarded them to HEPP’s administrators, employees and other stakeholders in three groups. Additional phone interviews were conducted and the quantitative as well as qualitative data collected was evaluated and displayed in tables and figures in this study. Data analysis demonstrates a few shortcomings, weaknesses and strengths that are discussed in detail and conclusive proposals are presented through the conclusion section in enhancement of HEPP’s services to the advantages of stakeholders and employees of HEPP with a complete consideration for HEPP’s well being and awareness of its competitors. Although this study is limited in scope it highlights what needs to be done in HEPP or similar hydro electric organizations in Iran, and it can act as a stepping stone for further research and analysis of hydro electrical demand and supply issues in Yazd region of Iran.

Thesis (MTech (Quality (Engineering)))--Cape Peninsula University of Technology, 2016. / The research study establishes the maturity level of the outage process of the Outage Management Department at Eskom. The outage process started in 2012 to contribute to the effective planning and execution of outages. The successful completion of outages depends on effective planning and execution of an outage. At the time of the research study, poor outage performance at Eskom’s power stations contributed to load shedding of electricity in South Africa. The research problem statement reads as follows: The absence of an outage process maturity indicator diminishes the ability of the Outage Management Department (OMD) to comprehend the current process maturity level. The research question: Will the Outage Management Department be able to identify improvement opportunities if the maturity level of the outage process is established? iv The key research objectives are: • To consider how process maturity enables improvement. • To identify critical elements in an outage process. • To determine what is included in outage planning, control and improvement. • To identify a suitable process maturity model. • To identify a measurement instrument to determine the maturity level of Eskom’s outage process The research study uses a descriptive research design and applies the survey research method. Greener and Martelli’s (2015: Online) Business Research Process (Sources: Greener & Martelli, 2015: Online) is used together with Farooq’s Research Steps for Survey Research (2015, Online). The survey questionnaire adopted from Smith’s Maintenance Planning and Scheduling Maturity Matrix (2013: Online) was used to develop the survey questionnaire. The author developed the Outage Management Maturity Framework by combining Business Process Management Maturity model and a Maintenance Planning and Scheduling Maturity Matrix. The research finding is that a process maturity model can determine the maturity level of the outage process and is useful as a process improvement tool. The research findings rank the maturity level of the outage process at Level 2, Experimenting.

Thesis (MTech (Quality))--Cape Peninsula University of Technology, 2017. / The research study establishes the maturity level of the outage process of the Outage Management Department at Eskom. The outage process started in 2012 to contribute to the effective planning and execution of outages. The successful completion of outages depends on effective planning and execution of an outage. At the time of the research study, poor outage performance at Eskom’s power stations contributed to load shedding of electricity in South Africa. The research problem statement reads as follows: The absence of an outage process maturity indicator diminishes the ability of the Outage Management Department (OMD) to comprehend the current process maturity level. The research question: Will the Outage Management Department be able to identify improvement opportunities if the maturity level of the outage process is established? The key research objectives are: • To consider how process maturity enables improvement. • To identify critical elements in an outage process. • To determine what is included in outage planning, control and improvement. • To identify a suitable process maturity model. • To identify a measurement instrument to determine the maturity level of Eskom’s outage process The research study uses a descriptive research design and applies the survey research method. Greener and Martelli’s (2015: Online) Business Research Process (Sources: Greener & Martelli, 2015: Online) is used together with Farooq’s Research Steps for Survey Research (2015, Online). The survey questionnaire adopted from Smith’s Maintenance Planning and Scheduling Maturity Matrix (2013: Online) was used to develop the survey questionnaire. The author developed the Outage Management Maturity Framework by combining Business Process Management Maturity model and a Maintenance Planning and Scheduling Maturity Matrix. The research finding is that a process maturity model can determine the maturity level of the outage process and is useful as a process improvement tool. The research findings rank the maturity level of the outage process at Level 2, Experimenting.

Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-01-10T17:04:37Z No. of bitstreams: 1 raphaelfranciscofirmianoteixeira.pdf: 2043800 bytes, checksum: c1621a5e2f6c91e329bbc4cd21d1701b (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-01-23T11:53:03Z (GMT) No. of bitstreams: 1 raphaelfranciscofirmianoteixeira.pdf: 2043800 bytes, checksum: c1621a5e2f6c91e329bbc4cd21d1701b (MD5) / Made available in DSpace on 2018-01-23T11:53:03Z (GMT). No. of bitstreams: 1 raphaelfranciscofirmianoteixeira.pdf: 2043800 bytes, checksum: c1621a5e2f6c91e329bbc4cd21d1701b (MD5) Previous issue date: 2017-08-30 / Frequentemente os valores dos parâmetros exigidos em um Contrato de Fornecimento de Energia Elétrica para consumidores não industriais são estimados com base na previsão de demanda utilizando o método “Naive”, por vezes, com algum ajuste empírico, o que pode gerar um contrato não-ótimo para o consumidor. Exemplo desse tipo de consumidor são as universidades, principalmente as públicas, por possuírem dimensões físicas consideráveis. Em consumidores com esse tipo de comportamento, a elaboração de um perfil de demanda baseado em estudo do funcionamento das instalações torna-se algo muito complicado. Tendo em vista tratar-se de um consumidor pertencente ao Serviço Público, há a necessidade de Contratos definidos com critérios suficientemente claros, haja vista a pressão dos órgãos de controle. Mais ainda quando se considera o uso responsável e eficaz do dinheiro público. Portanto, métodos com base na previsão de demanda do consumidor, em função do seu histórico e capazes de uma aproximação maior com a realidade, seriam importantes para obter contratos com valores financeiros minimizados. Tendo os dados de Demandas Registradas da Universidade Federal de Juiz de Fora e dados auxiliares de Temperaturas e Calendário de Aulas, desenvolvemos um método que testa previsões realizadas por métodos lineares (Médias Móveis, ARIMA e Holt-Winters), com previsões realizadas por métodos não- lineares (Redes Neurais). Comparamos estas previsões, e a melhor foi levada a um processo de otimização utilizando Algoritmos Genéticos. Essa otimização revelou dados ótimos para o Contrato e os respectivos custos. A previsão com melhor desempenho foi a obtida utilizando-se Redes Neurais, sem os dados auxiliares. A otimização levou a escolha da Tarifa Azul, com previsão de ganhos econômicos para a UFJF. / The values of the parameters required in a Contract of Electric Power Supply are often estimated with bases on the demand forecasted using the “Naive” method, for nonindustrial consumers. Sometimes, the method suffers some empirical adjustment, which can generate a non-optimal contract for the consumer. Universities (in special the public ones) are examples of these type of consumers since they have considerable physical dimensions. The elaboration of a demand profile for these type of consumers, based on a study of the operation of the facilities, is a complicated task. Because the consumer is part of the Public Service, there is a need for Contracts defined with sufficiently clear criteria, given the pressure of the control bodies, particularly when the responsible and effective use of the public money is considered. Therefore, methods based on the consumer demand forecast in function of consumer’s history, and capable of greater approximation with reality, would be important to obtain contracts with minimized financial values. A method was developed based on data of the registered demands of the Federal University of Juiz de Fora (UFJF), and Temperature and Class Calendar adjuvant data. The method tests the predictions made by linear (Moving Averages, ARIMA and Holt-Winters) and by non-linear methods (Neural Networks). The predictions were compared and the best one was taken to an optimization process using Genetic Algorithms. The optimization revealed optimal data for the contract and its costs. The prediction that showed the best performance was the one obtained using Neural Networks without the adjuvant data. The optimization led to the choice of the “Tarifa Azul”, with possible economic gains for UFJF.

This diploma thesis is aimed at assessing the provision of emergency electric power supply to hospitals in South Bohemia. The chapter titled Present State briefly characterises the generation of electric power, the history of power plants in the Czech Republic, the power distribution system, it lists the basic elements of the power distribution system, including its stability and security. Among other things, it presents the term of blackout and its potential impact on the society. Furthermore, this chapter deals with the infrastructure in relation with the critical infrastructure and its history. At the end of this chapter, the functioning of health service is mentioned in relation to emergency situations, including the emergency sources used by hospitals. The research made use of the qualitative method of data collection and the data was acquired through the technique of controlled interviews and a secondary analysis of data from competent South Bohemian hospital staff who is responsible for or deal with the issue or providing emergency power supplies.

Die elektrische Energieform gewinnt im Kraftfahrzeug wegen ihrer Nutzungsvielfalt und sehr guten Steuerbarkeit für die Realisierung neuartiger Funktionen zunehmend an Bedeutung. Voraussetzung für ihren Einsatz ist eine zuverlässige und effiziente Bereitstellung durch das Kfz-Energiebordnetz. Dafür ist ein intelligentes Energiemanagement erforderlich, welches mit geeigneten Strategien die Leistungsflüsse im Energiesystem koordiniert. In dieser Arbeit werden die beiden Entwurfsziele der Zuverlässigkeit und der Effizienz bei der Entwicklung von elektrischen Energiemanagement-Strategien systematisch betrachtet. Es erfolgt eine Beschreibung und Zuordnung der einzelnen Ziele und Maßnahmen anhand der Energieflüsse und Wirkungsketten. Ein Schwerpunkt bildet dabei die Beherrschung von Lastwechseln im Bordnetz. Für Aussagen hinsichtlich einer effizienten Erzeugung elektrischer Energie erfolgt eine Untersuchung der Energiewandlungskette anhand analytischer Methoden und mit Hilfe einer simulationsgestützten Optimierung. Ein weiterer Fokus der Arbeit liegt in der Betrachtung zur Anwendung ökonomischer Modelle für eine Energiekoordination. Es werden die theoretischen Grundlagen der Mikroökonomie zusammengestellt und mögliche Funktionsstrukturen eines einseitigen und zweiseitigen Allokationsmechanismus verglichen und bewertet. Abschließend zeigen experimentelle Untersuchungen an einem Bordnetzprüfstand zum Lastwechselverhalten und die Integration eines Energiemanagement-Systems den praktischen Bezug zum realen System.

Die elektrische Energieform gewinnt im Kraftfahrzeug wegen ihrer Nutzungsvielfalt und sehr guten Steuerbarkeit für die Realisierung neuartiger Funktionen zunehmend an Bedeutung. Voraussetzung für ihren Einsatz ist eine zuverlässige und effiziente Bereitstellung durch das Kfz-Energiebordnetz. Dafür ist ein intelligentes Energiemanagement erforderlich, welches mit geeigneten Strategien die Leistungsflüsse im Energiesystem koordiniert. In dieser Arbeit werden die beiden Entwurfsziele der Zuverlässigkeit und der Effizienz bei der Entwicklung von elektrischen Energiemanagement-Strategien systematisch betrachtet. Es erfolgt eine Beschreibung und Zuordnung der einzelnen Ziele und Maßnahmen anhand der Energieflüsse und Wirkungsketten. Ein Schwerpunkt bildet dabei die Beherrschung von Lastwechseln im Bordnetz. Für Aussagen hinsichtlich einer effizienten Erzeugung elektrischer Energie erfolgt eine Untersuchung der Energiewandlungskette anhand analytischer Methoden und mit Hilfe einer simulationsgestützten Optimierung. Ein weiterer Fokus der Arbeit liegt in der Betrachtung zur Anwendung ökonomischer Modelle für eine Energiekoordination. Es werden die theoretischen Grundlagen der Mikroökonomie zusammengestellt und mögliche Funktionsstrukturen eines einseitigen und zweiseitigen Allokationsmechanismus verglichen und bewertet. Abschließend zeigen experimentelle Untersuchungen an einem Bordnetzprüfstand zum Lastwechselverhalten und die Integration eines Energiemanagement-Systems den praktischen Bezug zum realen System.