<p>QC 20160524</p>

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Este trabalho discute a produtividade na execução das instalações elétricas, em obras residenciais de múltiplos pavimentos. São apresentados os conceitos e as bases teóricas que balizaram este estudo; considerações e características dos processos envolvidos no serviço; dados coletados em campo e a análise desses dados, que são apresentados no formato de índices. O conjunto destas informações gera uma referência para a gestão de execução de instalações elétricas prediais com base em indicadores de produtividade. / This work discusses the productivity of electrical installations, in multi storey residential buildings. This study presents the concepts and theoretical bases that have been used; considerations and characteristics of the adopted processes; collected data in the field and the analysis of this data, which are presented in indicator format. All these information provides the basis to develop electrical installations management supported by the labor productivity knowledge.

This thesis is a case study of a 230 kV transmission line in Lao P.D.R. Grounding of electrical systems is essential for safety and reliability of the system. Several standards are developed for designing a grounding system when building new facilities but it is harder to find references when it is an expansion of an old system or when the area for grounding is inferior. The transmission line is routed over a high resistive limestone ridge, where the requirements from the design standard can not be fulfilled. During normal conditions, each tower can be properly grounded to earth with ground electrodes, but in this case the resistivity of the solid rock is too high. By studying different shield wires of different materials and improve the down lead conductor in each side of the mountain, a suitable solution can be found. The importance of grounding, general description of grounding techniques and the risks for human and equipment due to an electrical fault is also presented in this thesis.

Este trabalho discute a produtividade na execução das instalações elétricas, em obras residenciais de múltiplos pavimentos. São apresentados os conceitos e as bases teóricas que balizaram este estudo; considerações e características dos processos envolvidos no serviço; dados coletados em campo e a análise desses dados, que são apresentados no formato de índices. O conjunto destas informações gera uma referência para a gestão de execução de instalações elétricas prediais com base em indicadores de produtividade. / This work discusses the productivity of electrical installations, in multi storey residential buildings. This study presents the concepts and theoretical bases that have been used; considerations and characteristics of the adopted processes; collected data in the field and the analysis of this data, which are presented in indicator format. All these information provides the basis to develop electrical installations management supported by the labor productivity knowledge.

The master thesis project has been executed with the cooperation of Borlänge Energi, with the aim of reducing the high electric energy dependency which Moldova has on Ukraine, Transnistria and Russia. The project examines what reduction that would be possible by wind power installations on the existing electrical grid of Moldova. The installations should not surpass the capacity of the transmission lines or the voltage levels according to regulation. The southern regions of Moldova proved to have the best wind conditions and the locations of Besarabeasca, Zarnesti, Leovo, Ciadyr and Cimislia in the southern region were chosen for wind power installations. For the analysis a model over the Moldovan electrical system is constructed. Each of the five chosen locations is modelled with a generator symbolizing the wind power installation. The power flow software PSS/E is used to construct the model. To examine possible wind power installations different scenarios are created. The scenarios are executed with the southern regions 110 kV system as a focus area. All scenarios are analysed with a contingency analysis, where transmission lines in the focus region are tripped. The contingency analysis and the scenarios are automated using the programming language Python. An economic analysis shows payback periods for wind power investments in Moldova, the analysis also shows the sensitivity of the electricity price and discount rates. The project concludes that wind power installations are possible with the Moldovan electric grid as it looks today. The installations would result in reducing the high dependency of imported electrical energy.

Cette thèse s’inscrit dans le cadre de conception d’une stratégie de gestion de l’énergie dans un système hybride de génération d'énergie électrique composé d’une pile à combustible (PC) et un module de supercondensateurs (SC). La source hybride fournit une puissance maximale de 1,2 kW et sa conception implique des décisions concernant la sélection de l’architecture du système hybride ainsi que le choix de la topologie et le dimensionnement d’une unité de convertisseurs. La stratégie de gestion vise à satisfaire la demande d’énergie électrique de la charge et favoriser la consommation énergétique efficiente ; sa performance est évaluée en développant un simulateur qui comprend la dynamique des éléments mis en jeu : deux sources et l’unité de convertisseurs. Le générateur hybride est supposé alimenter un profil de consommation correspondant à un véhicule électrique, de ce fait un cycle standard de conduite en ville en échelle est demandé lors des simulations, ce qui permet d’évaluer la performance du générateur hybride et plus spécifiquement de la stratégie de gestion énergétique.Dans une première étape de cette thèse, un simulateur intégral a été construit avec des librairies de Simscape. Le simulateur est constitué des blocs de différents domaines, contenant des modèles fondamentaux des composants du système. Le block de pile à combustible modèle la dynamique d’un système BAHIA® (400 W - 1100 W, 0 A - 70 A nominale) et le block de supercondensateur modèle les cycles charge-décharge d’un module Maxwell de 400 F et 16 V. Un onduleur de tension pont complet avec convertisseur élévateur conditionne l’énergie délivrée par la pile à combustible et un convertisseur bidirectionnel (buck-boost) est connecté au module de supercondensateurs afin de conditionner les cycles de charge-décharge. L’unité des convertisseurs a été dimensionné, puis, un modèle moyen de petits signaux a été formulé afin de décrire la dynamique de ces dispositifs. Les différents composants ont été intégrés dans l’environnement Simulink. Dans une deuxième étape, la stratégie de gestion énergétique a été conçue en considérant les caractéristiques et performances des sources ; le résultat est une stratégie de trois niveaux hiérarchiques, dont l’aspect principal es la définition des lois de commande locales et globale. Dans une troisième étape, le système complet est évalué en termes du niveau d’utilisation des sources, du domaine d’opération de la pile à combustible, et de l’accomplissement des objectifs des commandes locales et global, qui engagent notamment le SOC des supercondensateurs et la régulation de la tension du générateur hybride. / Energy generation from fossil fuels combustion is predicted to have severe future impacts in the world’s economy and ecology. Fuel cells and supercapacitors are an alternative power source, environmentally friendly.This dissertation presents a regulation architecture developed to coordinate a hybrid renewable source for typical solicitations of electric vehicles in a scaled operating range of 1 kW. The hybrid system is composed of a Polymer Electrolyte Membrane (PEM) fuel cell module, a supercapacitors bank and their respective power conditioning units. In order to optimize the overall operation, the proposed strategy is organized into three hierarchical levels, and the power demand for each energy source is determined in real time with a basis on a frequency distribution and a cutoff frequency, defined in accordance with the dynamical capabilities of the sources.Even if numerous researches have been reported on the subject, few studies have taken into account the proper dynamics of each source in order to optimize the global performance of the hybrid power supply.The goal of this work is to implement a complete simulator integrating not only dynamical models of each energy source, but also dynamical models of the power conditioning units. The control strategy consists of nested loops, arranged in three functional levels of hierarchy. The central idea is to find the optimal set point for each energy source, according to their own physical properties. Contrary to the existing control strategies, this strategy dynamically calculates the appropriate power demand for each energy source. Due to the complexity of the system, cascade control loops are proposed, organized into blocks, according to the system functionality and dynamics.A functional simulation is obtained, where the system ensures the adequate supercapacitor state of charge and soft current demands to keep the fuel cell working in its safe operating region. Thus, lower fuel consumption and rapid response to load demands are guaranteed to improve efficiency.Results demonstrate that the control strategy allows the regulation of the DC bus voltage under UDDS and ECE-15 driving cycles as load profiles. The fuel cell works within its maximum efficiency region, without falling in the degradation zone. In addition, the supercapacitor state of charge remains within the recommended range.

The increasing use of electrical technologies within on-board (aircraft, road vehicle, train and ship) power systems is resulting in complex and highly dynamic networks in which energy storage devices have an important role to play, for example to resolve the instantaneous mismatch between load demand and power availability or to provide the flexibility to optimise overall performance. In this thesis, a multi-level controller for a super-capacitor based energy storage system (ESS) is designed, simulated, emulated and validated experimentally to show its effectiveness in smoothing load and managing state-of-charge of the energy storage system. This thesis first investigates the low level control of the dual-interleaved converter, particularly at light load where seven discontinuous conduction modes (DCMs) appear. A thorough analysis of these operating modes is given and validated by simulations and experiments. Based on the analysis, an inverse-model-based feed-forward current controller is implemented, offering a low level converter control interface which serves the high level supervisory controller within the energy storage system. Two supervisory control methods have been proposed in this thesis, both producing a super-capacitor current reference for the low level controller. The first supervisory control not only manages the energy within the ESS but also shields the primary power source from rapid load transients , which has been examined through an emulated ESS in the Intelligent Electrical Power Network Evaluation Facility (IEPNEF). A more advanced supervisory controller is then proposed which in addition to the benefits of the first control, regulates the rate-of-change in power that is drawn from the primary power source in the system. The proposed second control method is implemented within a real super-capacitor energy storage system in IEPNEF, with both simulation and experimental results successfully demonstrating and validating its operation.

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