<p>Detta examensarbete beskriver hur en Monte Carlo simulering (MCS) kan användas för tillförlitlighetsanalys av ett eldistributionssystem. Metoden har implementerats i verktyget RADPOW som nu kan utföra både analytiska och numeriska beräkningar. Angreppssättet för att utveckla denna MCS metod i RADPOW innefattade följande aktiviteter:</p><p>• Vidareutvecklade av RADPOW med införandet av ett grafiskt användargränssnitt för Windows.</p><p>• Utveckling och implementering av en iterativ analytisk metod för känslighetsanalys av eldistributionssystem i RADPOW.</p><p>• Utveckling och implementering av MCS metoden i RADPOW, vilken placerades i en fristående modul kallad Sim.</p><p>Den implementerade MCS metoden har validerats i en jämförande studie innefattande två testsystem med datorprogrammet NEPLAN. Resultat från denna studie visar att MCS metoden ger samma resultat som den analytiska metoden i RADPOW och det kommersiella verktyget NEPLAN.</p> / <p>This master thesis describes an implementation of a Monte Carlo Simulation (MCS) method for reliability assessment of electrical distribution systems. The method has been implemented in the reliability assessment tool RADPOW which now is able to perform both analytical and simulation evaluations. The main contributions within this thesis includes the following activities;</p><p>• Further development of RADPOW by the introducing of a graphical user interface for Windows.</p><p>• Development and implementation of an analytical sensitivity analysis routine for RADPOW.</p><p>• Development and implementation of a sequential MCS method in RADPOW in a stand alone module referred to as Sim.</p><p>The implemented MCS method has been validated in a comparable study for two case systems by a commercial software NEPLAN. Results shows that the implemented MCS method provides the same results as the analytical method in RADPOW and the NEPLAN software.</p>

Dans le domaine de la distribution d’électricité, l’arrivée progressive de production décentralisée rend certains réseaux de distribution exportateurs de puissance, au point où des investissements sont nécessaires pour permettre l’évacuation de la puissance produite. La progression de l’instrumentation des réseaux permet au distributeur d’obtenir des informations de plus en plus riches sur la production décentralisée et la question d’intégrer celles-ci dans les procédés de planification français se pose. À partir de relevés de production, on vérifie que les situations de référence utilisées pour dimensionner le réseau présentent un risque d’occurrence suffisant pour nécessiter des investissements. Si des solutions offrant de la flexibilité sont utilisées, celles-ci peuvent être intégrées au processus de planification. Une étude technico-économique est nécessaire et des méthodes sont proposées pour estimer les fréquences de forte production et la dispersion possible pour un ou plusieurs producteurs. Des modèles simples de loi jointe sont proposés. Le cas pratique de l’effacement de production est testé sur des réseaux considérés réalistes. À partir des relevés réels et des modèles, l’effacement est comparé à l’option d’investir au niveau du poste source. Des abaques de décision sont tracés permettant une projection rapide du distributeur. Par ailleurs dans une optique d’utilisation de l’effacement pour gérer des contraintes intra-réseau, une méthode de calcul de load flow probabilisé est proposée ; celle-ci permet d’estimer rapidement la quantité d’effacement requise et de réaliser un comparatif économique entre plusieurs options. / In the field of electricity distribution, some grids are more and more frequently exporters due to the gradual arrival of decentralized generation. Some grid investments are required to allow the evacuation of the power generated. As more and more information about decentralized production are available for the DSO, the question of integrating them into the planning processes arises.From data of energy production, it appears that the current situations tested for sizing the grid are likely to be reached on a several years basis. If consumption or production flexibilities are used, these can be integrated into the planning process. A technical and economic study is needed and methods are proposed to estimate the frequencies of high production and possible dispersion for one or more producers. Simple models of joint distribution are proposed.The practical case of curtailing production has been tested on networks with realistic scenarios of producers arrival. From actual data and previous models, curtailment and reinforcement are compared on a technico-economic basis. A abacus is plotted as a simple decision tool for the DSO. The question of using curtailment to defer or avoid intra-grid investment has also been investigated ; a calculation method of probabilistic load flow is proposed; it gives a quick and accurate estimation of the energy to curtail in order to avoid a constraint.

Made available in DSpace on 2014-06-11T19:22:33Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-02-24Bitstream added on 2014-06-13T19:06:59Z : No. of bitstreams: 1 alves_rp_me_ilha.pdf: 1636703 bytes, checksum: 68dadb3a2996ae56b4ce5e5e3e063a2d (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / O presente trabalho apresenta o desenvolvimento de uma formulação linear inteira mista (equivalente à formulação não linear inteira mista) para resolver o problema de alocação de reguladores de tensão ao longo dos alimentadores primários de sistemas de distribuição de energia elétrica radiais, com o objetivo de melhorar o perfil da magnitude de tensão, reduzir as perdas de potência ativa da rede e a minimização dos custos de instalação dos equipamen-tos. Na formulação proposta, o cálculo do ponto de operação em regime permanente de um sistema de distribuição radial é modelado matematicamente usando expressões lineares. O uso de um modelo de programação linear inteira mista garante a convergência para a solução óti-ma usando ferramentas de otimização clássica existentes. Os sistemas testes de 70-, 136-, 202- e 400-nós são utilizados para mostrar a precisão do modelo matemático, assim como também a eficiência da técnica de solução proposta para resolver o problema de alocação de reguladores de tensão em um sistema de distribuição radial / This work shows the development of a mixed integer linear formulation to solve the voltage regulators allocation problem in radial electrical distribution systems, with the goal of improving the voltage magnitude profile, reducing the active power losses and mini-mizing the investment cost. In the proposed formulation, the steady-state operation point of the radial distribution system is modeled through linear expressions. The use of a mixed-integer linear formulation guarantees convergence to optimality using existing optimization software. The 70-, 136-, 202- and 400-node test systems are used in order to show the accura-cy of the mathematical model as well as the efficiency of the proposed solution technique to solve the allocation problem of voltage regulators in a radial distribution system

A troca de informações entre os vários sistemas de gerenciamento e outros sistemas de informação de uma empresa do setor elétrico não é apenas desejada, mas na maioria dos casos, necessária. Com a necessidade desenvolveu-se uma pesquisa com o objetivo de descrever as metodologias de integração entre Sistemas de Informações Geográficas e Sistemas de Projetos de Redes de Distribuição, incluindo referências a diversos trabalhos de integração no Brasil e no mundo. Como exemplo e caso prático, utilizou-se uma metodologia desenvolvida para a concessionária de distribuição de energia elétrica AES Eletropaulo. / The information interchanges between management systems and others information systems of an electrical distribution company is not only desirable, but in most cases necessary. Due this necessity it was developed one research aiming to describe the integration methodologies between geographic information systems and electrical grid expansion designer systems, including references for some integration works in Brazil and in World. As a practical example, it was used one methodology developed for the electrical distribution company AES Eletropaulo.

Orientador: Marcos Julio Rider Flores / Banca: Rubén Augusto Romero Lázaro / Banca: Carlos Alberto Castro Júnior / Resumo: O presente trabalho apresenta o desenvolvimento de uma formulação linear inteira mista (equivalente à formulação não linear inteira mista) para resolver o problema de alocação de reguladores de tensão ao longo dos alimentadores primários de sistemas de distribuição de energia elétrica radiais, com o objetivo de melhorar o perfil da magnitude de tensão, reduzir as perdas de potência ativa da rede e a minimização dos custos de instalação dos equipamen-tos. Na formulação proposta, o cálculo do ponto de operação em regime permanente de um sistema de distribuição radial é modelado matematicamente usando expressões lineares. O uso de um modelo de programação linear inteira mista garante a convergência para a solução óti-ma usando ferramentas de otimização clássica existentes. Os sistemas testes de 70-, 136-, 202- e 400-nós são utilizados para mostrar a precisão do modelo matemático, assim como também a eficiência da técnica de solução proposta para resolver o problema de alocação de reguladores de tensão em um sistema de distribuição radial / Abstract: This work shows the development of a mixed integer linear formulation to solve the voltage regulators allocation problem in radial electrical distribution systems, with the goal of improving the voltage magnitude profile, reducing the active power losses and mini-mizing the investment cost. In the proposed formulation, the steady-state operation point of the radial distribution system is modeled through linear expressions. The use of a mixed-integer linear formulation guarantees convergence to optimality using existing optimization software. The 70-, 136-, 202- and 400-node test systems are used in order to show the accura-cy of the mathematical model as well as the efficiency of the proposed solution technique to solve the allocation problem of voltage regulators in a radial distribution system / Mestre

This thesis deals with the applications of graph theory towards the electrical distribution networks that transmit electricity from the generators that produce it and the consumers that use it. Specifically, we establish the substation and bus network as graph theoretical models for this major piece of electrical infrastructure. We also generate substation and bus networks for a wide range of existing data from both synthetic and real grids and show several properties of these graphs, such as density, degeneracy, and planarity. We also motivate future research into the definition of a graph family containing bus and substation networks and the classification of that family as having polynomial expansion.

In this research, the impact of solar thermal water heaters on the electric water heating load curve in a residential distribution circuit is analyzed with realistic hot water draw profiles. For this purpose, the electric and solar thermal water heater models are developed in MATLAB and validated with results from GridLAB-D and TRNSYS respectively. The solar thermal water heater model is developed for two types of collectors namely the flat plate and evacuated glass tube collector. Simulations are performed with the climate data from two cities - Madison, WI and Tampa, FL - which belong to two very different climate zones in the United States. Minute-by-minute electric energy consumptions in all three configurations of water heaters are modeled for a single water heater as well as a residential distribution circuit with 100 water heaters for daily as well as monthly time frames. The research findings include: The electric energy saving potential of a solar thermal water heater powered by auxiliary electric element is in the range of 40-80% as compared to an all-electric water heater depending on the site conditions such as ambient temperature, sunshine and wind speed. The simulation results indicate that the energy saving potential of a solar thermal water heater is in the range of 40-70% during winter and 60-80% during summer. Solar thermal water heaters aid in reducing the peak demand for electric water heating in a distribution feeder during sunshine hours when ambient temperatures are higher. The simulation results indicate that the peak reduction potential of solar thermal water heaters in a residential distribution feeder is in the range of 25-40% during winter and 40-60% during summer. The evacuated glass tube collectors save an additional 7-10% electric energy compared to the flat plate collectors with one glass pane during winter and around 10-15% during summer. The additional savings result from the capability of glass tube collectors to absorb ground reflected radiation and diffuse as well as direct beam radiation for a wider range of incidence angles. Also, the evacuated glass tube structure helps in reducing wind convective losses. From the simulations performed for Madison, WI and Tampa, FL, it is observed that Tampa, FL experiences more energy savings in winter than Madison, WI, while the energy savings are almost the same in summer. This is due to the fact that Tampa, FL has warmer winters with higher ambient temperatures and longer sunshine hours during the day compared to Madison, WI while the summer temperatures and sunshine hours are almost the same for the two cities. As expected, the simulation results prove the fact that lowering the hot water temperature set point will result in the reduction of electricity consumption. For a temperature reduction from 120 deg. F to 110 deg. F, electric water heaters save about 25-35% electric energy whereas solar thermal water heaters save about 30-40% auxiliary electric energy for the same temperature reduction. For the flat plate collectors, glass panes play an important role in auxiliary electric energy consumption. Flat plate collectors with two glass panes save about 10-15% auxiliary electric energy compared to those with no glass panes and about 3-5% energy saving compared to collectors with one glass pane. This is because there are reduced wind convective losses with glass panes. However, there are also transmittance losses from glass panes and there are upper limits on how many glass panes can be used. Results and findings from this research provide valuable insight into the benefits of solar thermal water heaters in a residential distribution feeder, which include the energy savings and peak demand reduction. / Master of Science

The goal of the work reported herein has been to model aspects of the electrical distribution system of an all-electric ship (AES) and to couple electrical load behavior with the thermal management network aboard the ship. The development of a thermally dependent electrical network has built upon an in-house thermal management simulation environment to replace the existing steady state heat loads with dynamic, thermally dependent, electrical heat loads. Quantifying the close relationship between thermal and electrical systems is of fundamental importance in a large, integrated system like the AES. This in-house thermal management environment, called the Dynamic Thermal Modeling and Simulation (DTMS) framework, provided the fundamental capabilities for modeling thermal systems and subsystems relevant to the AES. The motivation behind the initial work on DTMS was to understand the dynamics of thermal management aboard the ship. The first version, developed in 2007, captured the fundamental aspects of system-level thermal management while maintaining modularity and allowing for further development into other energy domains. The reconfigurable nature of the DTMS framework allowed for the expansion into the electrical domain with the creation of an electrical distribution network in support of thermal simulations. The dynamics of the electrical distribution system of the AES were captured using reconfigurable and physics-based circuit elements that allow for thermal feedback to affect the behavior of the system. Following the creation of the electrical network, subsystems and systems were created to simulate electrical distribution. Then, again using the modularity features of DTMS, a thermal resistive heat flow network was created to capture the transient behavior of heat flow from the electrical network to the existing thermal management framework. This network provides the intimate link between the thermal management framework and the electrical distribution system. Finally, the three frameworks (electrical, thermal resistive, and thermal management) were combined to quantify the impact that each system has relative to system-level operation. Simulations provide an indication of the unlimited configurations and potential design space a user of DTMS can explore to explore the design of an AES. / text

Master of Science / Department of Electrical and Computer Engineering / Medhat M. Morcos / The inclusion of Selective Coordination in the NEC since the 2002 revision and the expansion of applications for which coordination of Over-current Protective Devices is required have resulted changes in design approaches for electrical engineers. In order to meet the requirements of the NEC regarding Selective Coordination for secondary power systems within buildings, often, upstream protective devices need to be held-in to a short-circuit condition, thus increasing the Arc Flash Energy. Electrical engineers must understand the many aspects of Selective Coordination when approaching a project from the very beginning. Decisions made by the engineer regarding Selective Coordination will have influence on project cost, project timeline, robustness of the electrical equipment, and safety of personnel working near or on the electrical equipment. The main objectives of this report are to convey an understanding of the following: recent changes in requirements for Selective Coordination, implications of short-circuit analysis, impacts of selectively coordinated systems on Arc Flash Energy, risks surrounding Arc Flash Hazards, and design processes regarding Selective Coordination.

Os smart grids são tidos como a nova geração dos sistemas elétricos de potência, combinando avanços em computação, sistemas distribuídos e inteligência artificial para prover maiores funcionalidades sobre acompanhamento em tempo real da demanda e do consumo de energia elétrica, gerenciamento em larga escala de geradores distribuídos, entre outras, a partir de um sistema de controle distribuído sobre a rede elétrica. Esta abordagem alteraria fundamentalmente a maneira como se dá o planejamento e a operação de sistemas de distribuição, e há grandes possibilidades de pesquisa e desenvolvimento possibilitada pela busca de implementação destas funcionalidades. Com esse cenário em vista, o presente trabalho utiliza uma abordagem a partir do uso de sistemas multiagentes para estudar o gerenciamento de sistemas de distribuição, do ponto de vista da reconfiguração da topologia da rede, simulando as características de um smart grid. Nesta dissertação, foi desenvolvido um sistema multiagente para simulação computacional de um sistema de distribuição elétrico do tipo smart grid, buscando executar a reconfiguração topológica do sistema a partir de dados de carga capturados de forma distribuída pelos agentes dispersos na rede elétrica. Espera-se que o desenrolar da pesquisa conduza à vários estudos sobre algoritmos e técnicas que melhor implementem tais funcionalidades a serem transpostas para um ambiente de produção. / Smart grids are taken as the new generation of electric power systems, combining advances in computing, distributed systems and artificial intelligence to provide more features on real-time monitoring of demand and consumption of electricity, managing large-scale distributed generators, among others, from a distributed control system on the grid. This approach fundamentally alter the way how is the planning and operation of distribution systems, and there are great possibilities for research and development offered in the quest to implement these features. With that environment, this text uses an approach through the use of multi-agent systems to study the management of the distribution system, from the reconfiguration of grid topology, simulating the characteristics of a smart grid. In this text, was developed a multiagent system to computational simulation of a distribution system like smart grid to topological reconfiguration, from datas collected for agents in electrical grid. It is expected that the conduct of research leads to several studies about better algorithms and techniques that would implement such functionality in a production environment.