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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Affärsmöjligheter med Smarta Elnät : En studie som undersöker möjligheter och hinder i utvecklingen av det svenska elsystemet / Business opportunities concerning Smart Grids

Ewing, Mikael January 2012 (has links)
Distributed, renewable generation-units and more efficient use of electric power,demands a developed electric grid. This grid is often referred to as the “Smart Grid”. This future electric system rise expectations among actors in the existing electricmarket. International organizations share visions of opportunities for electricityconsumers and new actors, ready to enter the market. At the same time, electricutility companies may question the need for some of these upcoming changes, as theyare sometimes expected to lead the development. This paper therefore seeks to investigate the business opportunities related to SmartGrids. This is done throughout interviews, literature-studies and analysis usinginnovation-development theories. Primary focus of the paper is directed towards theelectric utility companies, secondary towards electric consumers. Business opportunities for utility companies are found to be primary associated withoperation and maintenance aspects of the grid. Developed control-systems andupdated maintenance strategies may increase the overall system knowledge and thequality of the distribution. Cost-reduction activities as these are probably results ofthe revenue-cap regulation controlling grid companies. Future consumers may benefit,socially and economically, from solutions visualizing and controlling different electriccomponents in the real estate. At the same time the development of Smart Grids is a rather slow process, partlybecause of large amount of system-components and partly because of existing rulesand laws concerning the electric system. In order to identify future opportunitieswithin Smart Grids, it is crucial to gain knowledge of the system and to satisfy realneeds or problems.
22

Protection system representation in the Electromagnetic Transients Program /

Chaudhary, Arvind K. S., January 1991 (has links)
Thesis (Ph. D.)--Virginia Polytechnic Institute and State University, 1991. / Vita. Abstract. Includes bibliographical references (leaves 187-192). Also available via the Internet.
23

Inherent structural characteristics based optimal operation of power system networks.

Sikiru, Tajudeen Humble. January 2014 (has links)
D. Tech. Electrical Engineering. / Discusses the operations and planning of power systems is a complex task, mostly with many intricate manoeuvres to ensure reliable network operations such that the active power losses are reduced and the network voltage proles are improved without compromising the network security. Then the question is, what is the role of the inherent structural characteristics in solving power system problems? Although, the inherent structural characteristics of a power system network are embedded within the load flow formulation to some extent, their full capabilities in solving the problems of the network have not been holistically investigated. The fundamental circuit theory law (Ohm's law), which is a linear equation, clearly demonstrates the importance of the structural topology of the network. However, this importance is confounded by the reformulation of the fundamental law to nonlinear load flow equations. This research investigated the role of the inherent structural characteristics in solving power system problems from a circuit theory perspective.
24

Technological Externalities and Economies of Vertical Integration in the Electric Utility Industry

Nemoto, Jiro, Mika, Goto January 2004 (has links)
No description available.
25

The application of artificial neural networks to the fast assessment of first swing transient stability on a multimachine power system /

Allen, Geoffrey Neil Unknown Date (has links)
Thesis (PhD) -- University of South Australia, 1993
26

The application of artificial neural networks to the fast assessment of first swing transient stability on a multimachine power system /

Allen, Geoffrey Neil Unknown Date (has links)
Thesis (PhD) -- University of South Australia, 1993
27

Design and development of a smart inverter system

Adekola, Olawale Ibrahim January 2015 (has links)
Thesis (MTech (Electrical, Electronic and Computer Engineering))--Cape Peninsula University of Technology, 2015. / The growing interest in the use of solar energy to mitigate climate change, reduction in the cost of PV system and other favourable factors have increased the penetration of the PV(Photovoltaic) systems in the market and increase in the worldwide energy supply. The main component in a DG is a smart inverter connected in a grid-tied mode which serves as a direct interface between the grid and the RES (Renewable Energy System). This research work presents a three phase grid-tied inverter with active and reactive power control capabilities for renewable energy sources (RES) and distributed generators (DG). The type of the inverter to be designed is a Voltage Source Inverter (VSI). The VSI is capable of supplying energy to the utility grid with a well regulated DC link at its input. The solution this project proposes is an implementation of the designed filter to effectively reduce the harmonics injected into the grid to an acceptable value according to standards and also an approach to control the real and reactive power output of the inverters to help solve the problems of instability and power quality of the distribution system. The design, modelling and simulation of the smart inverter system is performed in MATLAB/SIMULINK software environment. A 10 kW three-phase voltage source inverter system connected to the utility grid was considered for this research. Series of simulations for the grid-connected inverter (GCI) model was carried out using different step changes in active and reactive power references which was used to obtain the tracking response of the set power references. The effectiveness of the control system which was designed to track the set references and supply improved power quality with reduced current ripples has been verified from the simulation results obtained.
28

Toward an Urban Political Ecology of Energy Justice: The Case of Rooftop Solar in Tucson, AZ

Franklin, Remington Santiago, Franklin, Remington Santiago January 2017 (has links)
A central challenge of the twenty-first century is to transition to a low-carbon energy system to reduce the risks of climate change. For Pima County, Arizona, where electricity accounts for the majority of greenhouse gas emissions, this requires rapid deployment of grid-tied renewable energy resources. In light of this challenge, photovoltaic solar has emerged as an important solution, providing the top source of new US electric generating capacity installed in 2016. However, there is still no consensus about the optimal scale for solar (centralized power plants, or small, decentralized systems) and the socio-economic implications for low income households. This thesis explores the implications of rooftop solar for energy justice through empirical research about a southern Arizona electric utility rate case. Utilities argue that existing rate structures shift costs from solar owners to lower-income ratepayers, while critics say the utility's proposed rate changes are unjust and that rooftop solar benefits all ratepayers. Drawing on my empirical data and an urban political ecology (UPE) approach, I analyze competing narratives that speak to three types of justice: distributive, procedural, and recognition. While dominant justice claims revolve around the distribution of costs through rates, competing narratives emphasize procedural and recognition (in)justice. Focusing on political economy, power relations, and the materiality of the grid, I reframe the utility’s cost shift argument as a strategic narrative and explain why this justice claim is ultimately validated. I propose that UPE can further an energy justice analysis by understanding procedural and recognition injustice as systemic products of rate of return regulation and the material configuration of the electric grid.
29

An expert system for protection system design of interconnected electrical distribution circuits

Thompson, Jeffrey Craig 06 June 2008 (has links)
As necessity for improvement in system operation demands the implementation of distribution automation, design of the protection system becomes more involved. Several goals of distribution automation -- improved customer reliability, reduced systems losses, and balancing of substation loading -- are dependent on the ability to perform automatic circuit reconfigurations. A prerequisite for implementing automatic circuit reconfiguration is that the protection system design must operate properly for all configurations. An integrated expert system for the protection system design of interconnected distribution circuits has been developed using the DANE engineering workstation. The expert system incorporates the basic requirements and guidelines as specified by IEEE for protection system design. The expert system uses a relational database management system, integrates system data, and provides a graphical user interface. The expert system incorporates both procedural and declarative, or query, operating modes. Rules dealing with the coordination, placement and selection of protective devices are presented that are used to dynamically, incorporate expert knowledge into the knowledge base. The protection system designer controls which rules are implemented in the design. An example protection system design is presented using the integrated expert system developed for DANE. The example problem consists of three interconnected distribution circuits. Dynamic knowledge, created by the expert system from the rules and system data, is used in the design. System data is presented pertaining to the circuits along with the created dynamic knowledge. The implemented rules dealing with the coordination, placement and selection of protective devices are presented, along with all associated parameter values. The final protection system design and results are presented in a research report. / Ph. D.
30

A Decision Support System for the Electrical Power Districting Problem

Bergey, Paul K. 28 April 2000 (has links)
Due to a variety of political, economic, and technological factors, many national electricity industries around the globe are transforming from non-competitive monopolies with centralized systems to decentralized operations with competitive business units. This process, commonly referred to as deregulation (or liberalization) is driven by the belief that a monopolistic industry fails to achieve economic efficiency for consumers over the long run. Deregulation has occurred in a number of industries such as: aviation, natural gas, transportation, and telecommunications. The most recent movement involving the deregulation of the electricity marketplace is expected to yield consumer benefit as well. To facilitate deregulation of the electricity marketplace, competitive business units must be established to manage various functions and services independently. In addition, these business units must be given physical property rights for certain parts of the transmission and distribution network in order to provide reliable service and make effective business decisions. However, partitioning a physical power grid into economically viable districts involves many considerations. We refer to this complex problem as the electrical power districting problem. This research is intended to identify the necessary and fundamental characteristics to appropriately model and solve an electrical power districting problem. Specifically, the objectives of this research are five-fold. First, to identify the issues relevant to electrical power districting problems. Second, to investigate the similarities and differences of electrical power districting problems with other districting problems published in the research literature. Third, to develop and recommend an appropriate solution methodology for electrical power districting problems. Fourth, to demonstrate the effectiveness of the proposed solution method for a specific case of electric power districting in the Republic of Ghana, with data provided by the World Bank. Finally, to develop a decision support system for the decision makers at the World Bank for solving Ghana's electrical power districting problem. / Ph. D.

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