This dissertation proposes new methods to improve the efficiency of electricity markets with respect to market monitoring and reserve allocation. We first present new approaches to monitor the level of competition in electricity markets, a critical task for helping the markets function smoothly. The proposed approaches are based on economic principles and a faithful representation of transmission constraints. The effectiveness of the new approaches is demonstrated by examples based on medium- and large-scale electric power systems. We then propose a new system-operation model using stochastic optimization to systematically allocate reserves under uncertainty. This model aims to overcome the difficulties in both system and market operations caused by the integration of wind power, which results in a higher degree of supply uncertainty. The numerical examples suggest that the proposed model significantly lower the operation costs, especially under high levels of wind penetration. / text

Syfte: Syftet med denna studie var att utvärdera tillförlitligheten av informationen som ambulanspersonalen får från sjukvårdens larmcentral. Frågeställningen är i vilken utsträckning utalarmeringsinformationen stämmer överens med vad ambulans personalen gör för bedömningar väl framme på plats hos patienten. Metod: I denna studie användes en deskriptiv och korrelativ design och sambandet mellan de två variablerna utalarmeringsorsak och bedömt tillstånd. Studien inkluderade alla de larm som utalarmerats som prioritet 1A/B under insamlingsperioden, vecka 10 till vecka 18 2012, vilket resulterade i 62 larm. Resultat: Analysen av utalarmeringsorsak och bedömt tillstånd på plats visar en hög grad av överensstämmelse, kappa koefficienten 0.78. Det är enbart fem fall av sextiotvå, cirka 8 % som avviker utan någon rimlig förklaring, det kan därav antas att det medicinska beslutsstödet fungerar bra. Resultatet visar dock att det sker avvikanden när den intervjuande sjuksköterskan får ett larm med en medvetandepåverkad patient vid utalarmeringen. Slutsats: Studien visar att den utalarmeringsinformation som ambulansen får från sjukvårdens larmcentral anses fungera bra vid utalarmeringen av prioritering 1. Dock upptäcktes att det förekommer oförklarliga avvikande utalarmeringar, där det behövs mer forskning för att kunna utvärdera orsaken kring. / Objective: The objective of this study is to evaluate the reliability of the information that the ambulance crew receive from the emergency dispatch center. And in what extent the dispatch information is consistent with the ambulance crew’s evaluation of the patient’s condition. Method: In this study, a descriptive and correlative design and the relationship between two variables, emergency dispatch and assessed condition, and how well these were consistent with each other were evaluated. The study included all alarms that were dispatched as a priority 1A/B during the data collection period that lasted between week 10 to week 18 2012. This resulted in sixty-two alarms from the emergency dispatch center and the assessments made by the ambulance crew. Results: The analysis of the emergency dispatch and the assessed condition on the seen shows a high level of agreement, kappa coefficient 0.78. There are only five cases of sixty-two, about 8 % that’s without reasonable explanation. It can be assumed that the medical dispatch support tool works well. The result also shows that it sometimes occur mistakes when the interviewing nurse at the medical dispatch center had a patient whit impaired consciousness. Conclusion: The study shows that the dispatch information received from the emergency dispatch center should be considered to work well when dispatching priority 1 alarms. Furthermore, it was discovered that there are unexplained divergent dispatches, where more research is needed to evaluate the occurred mistakes.

The theme of Master project of Energetics engineer is to analize dispatch operating and problems of Distributing electricity network, sustaining analyse of nonfiction and generalize of experence practical work. Overlook dispatch operating functions and goals of Lithuanian electrical power company. Describe the information supply of dispatch team of Siauliai city. Analize the breakdown‘s information of Siauliai city department. Pending breakdowns count, the distribution time between breakdowns, present tne forecast of breakdowns.

Electric power is a basic requirement for present day life and its various economic sectors. To satisfy the ever-increasing needs for electricity, the number of generating units, transmission lines and distribution systems is rising steadily. In addition, electric power systems are among the most complex industrial systems of the modern age. Beside complexity, the generation of electric power is a main source of gaseous emissions and pollutants. The planning and operation of electric power systems must be done in a way that the load demand is met reliably, cost-effectively and in an environmentally responsible manner. Practitioners strive to achieve these goals for successful planning and operations utilizing various optimization tools. It is clear that the objectives to be satisfied are mostly conflicting. In particular, minimizing the fuel cost and the gaseous emissions are two conflicting and non-commensurate objectives. Therefore, multi-objective optimization techniques are employed to obtain trade-off relationships between these incompatible objective functions in order to help decision makers take proper decisions. In this thesis, two main power system operation problems are addressed. These are the economic load dispatch (ED) and the short-term hydro-thermal generation scheduling (STHTS). They are treated first as single-objective optimization problems then they are tackled as multi-objective ones considering the environmental aspects. These problems, single and multi-objective, are nonlinear non-convex constrained optimization problems with high-dimensional search spaces. This makes them a real challenge for any optimization technique. To obtain the optimal or close to optimal solutions, a modified bacterial foraging algorithm is proposed, developed and successfully applied. The bacterial foraging algorithm is a metaheuristic non-calculus-based optimization technique. The proposed algorithm is validated using diverse benchmark optimization examples before implementing it to solve the problems of this thesis. Various practical constraints are considered in the different cases of each problem. These include transmission losses, valve-point effects for both the ED and the STHTS problems and water availability and reservoir configurations for the STHTS problem. In all cases the optimal or near-optimal solution is obtained. For the multi-objective optimization cases, the Pareto optimal solution set that shows the trade-off relationship between the conflicting objectives is successfully captured.

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För många akut sjuka patienter är alarmeringssjukvården och ambulanssjukvården den första kontakten med sjukvården. Därför är det viktigt att dessa patienter prioriteras korrekt i förhållande till sjukdomstillståndets allvarlighetsgrad. Allra viktigast är det när patientens tillstånd är potentiellt akut livshotande, i situationer när tid är liv. Förutom det fysiska hotet kan tiden kännas outhärdligt lång innan ambulansen är på plats. Rädsla för att inte bli hittad och rädsla för att tillståndet ska försämras ytterligare kan innebära en skarp konfrontation med tankar om livets ändlighet. Syftet med studien var att kartlägga om det förelåg några skillnader i prioritering mellan alarmeringssjukvården och ambulanssjukvården, vid uppdrag där ambulanssjukvården bedömt att patienten led av ett potentiellt akut livshotande tillstånd. Alarmerings- och ambulansuppdrag från en region i sydvästra Sverige analyserades i en retrospektiv kvantitativ studie. Data inkluderade varje uppdrag under 2014 som ambulanssjukvården bedömt som Prio 1 vid avtransport (n=17 184). Av dessa uppdrag var 82,4 % (n=14 676) utlarmade som Prio 1 av alarmeringssjukvården. De resterande 17,6 % (n=3138) larmades ut som Prio eller Prio 3. Väntetiden för de patienter som bedömdes som Prio 2 eller Prio 3 vid utlarmningen var 100 % längre jämfört med som larmades ut som Prio 1. De bedömda tillstånd som oftast prioriterades upp var ”Ryggbesvär” (71,7 %) och ”Buk/urinvägar” (47,6 %). Kvinnor (19,7 %) prioriterades upp i högre utsträckning än män (18,3 %). Den största skillnaden förekom i gruppen ”Våld-misshandel” där andelen upprioriterade män var 14,7 % och andelen upprioriterade kvinnor var 41,7 %. Skillnader i prioritering i relation till ålder var högst för patienter som var 81 år eller äldre (26,0 %). Slutsatsen är att det förekommer omotiverade skillnader i vård för den aktuella patientgruppen. Skillnaderna är väsentliga eftersom tillståndens svårighetsgrad är bedömda som potentiellt akut livshotande och för en del av tillstånden är effekten av både åtgärder och väntan stor. Studien visar var skillnaderna är som störst, vilket gör det lättare att bedöma vilka vidare studier som sannolikt ger mest patientnytta.

Made available in DSpace on 2014-06-11T19:30:52Z (GMT). No. of bitstreams: 0 Previous issue date: 2006-07-21Bitstream added on 2014-06-13T19:00:51Z : No. of bitstreams: 1 amorim_ea_dr_ilha.pdf: 1200042 bytes, checksum: 598a8d060889d642964ac8c022c167e1 (MD5) / Esta pesquisa tem por objetivo o desenvolvimento de uma ferramenta computacional para a solução do problema de Fluxo de Potência Ótimo Multimercado (FPOM). O problema de fluxo de potência ótimo mutimercado é decomposto em vários subproblemas, uma para cada, submercado que compõe o sistema de potência interconectado. O modelo de decomposição utilizado permite resolver o problema de FPO considerando-se os modelos de mercado desverticalizados e centralizados e os desverticalizados e descentralizados. Neste contexto, a pesquisa desenvolvida considera o novo esquema de funcionamento dos mercados de energia elétrica, no qual é vi freqüentemente desejável preservar a autonomia de cada um dos submercados que compõem o sistema de potência multimercado. O problema de FPO proposto é modelado como um problema de otimização não-linear inteiro misto, com variáveis de controle contínuas e discretas e têm ênfase no despacho econômico da geração de potência ativa e nos ajustes dos controles de tensão. Além disso, este modelo de FPO trata os subproblemas ativo e reativo simultaneamente. Para a sua solução é apresentado um algoritmo evolutivo multiobjetivo, baseado no NSGA (Nondominated Sorting Genetic Algorithm), pois características do problema abordado dificultam a sua solução através das técnicas baseadas em programação matemática e justificam a escolha da metaheurística multiobjetivo. / This research is aimed at developing a computational tool for the solution of the Multimarket Optimal Power Flow (MOPF) problem. The multimarket optimal power flow problem is decomposed in various subproblems, one for each submarket that is part of the interconnected power system. The decomposition model used here allows solving the OPF problem considering the deregulated and centralized, and the deregulated and decentralized market models. In this context, the developed research takes into account the new functioning scheme of the electric power markets, viii where it is frequently desirable to preserve the autonomy of each one of those submarkets that compose the multimarket power system. The proposed OPF problem is modeled as a mixed integer non-linear optimization problem with continuous and discrete control variables, emphasizing the economic dispatch of the active power generation and the voltage control adjustments. In addition, this model of OPF deals simultaneously with the active and reactive subproblems. For its solution, a multiobjective evolutionary algorithm based on the NSGA (Nondominated Sorting Genetic Algorithm) is presented. The characteristics of the problem make difficult the utilization of techniques based on mathematical programming, justifying the adoption of a multiobjective metaheuristic.

This research focuses on improving the efficiency of power market operations by providing system operators additional tools for managing the costs of supplying and delivering electricity. A transmission topology control (TC) framework for production cost reduction based on a shift factor (SF) representation of branch and breaker flows is proposed. The framework models topology changes endogenously while maintaining linearity in the overall Mixed Integer Linear Programming (MILP) formulation. This work develops the DC lossless, and loss-adjusted TC formulations that can be used in a Day Ahead or intra-day market framework as well as an AC-based model that can be used in operational settings. Practical implementation choices for the Shift Factor formulation are discussed as well as the locational marginal prices (LMPs) under the TC MIP setting and their relation to LMPs without TC. Compared to the standard B-theta alternative used so far in TC research, the shift factor framework has significant computational complexity advantages, particularly when a tractably small switchable set is optimized under a representative set of contingency constraints. These claims are supported and elaborated by numerical results.

AN ABSTRACT OF THE THESIS OF Mohamed A. Abuella, for the Master of Science degree in Electrical and Computer Engineering, presented on May 10, 2012, at Southern Illinois University Carbondale. TITLE:STUDY OF PARTICLE SWARM FOR OPTIMAL POWER FLOW IN IEEE BENCHMARK SYSTEMS INCLUDING WIND POWER GENERATORS MAJOR PROFESSOR: Dr. C. Hatziadoniu, The aim of this thesis is the optimal economic dispatch of real power in systems that include wind power. The economic dispatch of wind power units is quite different of conventional thermal units. In addition, the consideration should take the intermittency nature of wind speed and operating constraints as well. Therefore, this thesis uses a model that considers the aforementioned considerations in addition to whether the utility owns wind turbines or not. The optimal power flow (OPF) is solved by using one of the modern optimization algorithms: the particle swarm optimization algorithm (PSO). IEEE 30-bus test system has been adapted to study the implementation PSO algorithm in OPF of conventional-thermal generators. A small and simple 6-bus system has been used to study OPF of a system that includes wind-powered generators besides to thermal generators. The analysis of investigations on power systems is presented in tabulated and illustrative methods to lead to clear conclusions.

A Geração Distribuída no Brasil tem crescido ao longo dos anos, especialmente na fonte fotovoltaica e na categoria que a ANEEL denomina microgeração distribuída, que são centrais geradoras de energia elétrica com potência instalada menor ou igual a 75 kW e conectada na rede de distribuição por meio de instalações de unidades consumidoras. Apesar dos problemas tradicionais que podem ocorrer com a inserção em larga escala, como maiores perdas e desvios de tensão, as placas fotovoltaicas, conectadas à rede de distribuição por meio de um inversor, trazem a possibilidade de controlar a tensão no ponto de conexão, manipulando-se o fator de potência de saída do inversor, controlando a potência reativa. Neste contexto, considerando o uso dos inversores inteligentes com possibilidade de envio de sinal remotamente ao operador e a possibilidade de criação de Centros de Despacho de Geração Distribuída (CDGD), este trabalho tem por objetivo propor uma metodologia de regulação de tensão centralizada utilizando unidades de microgeração fotovoltaicas, em redes de distribuição com larga inserção. A metodologia proposta utiliza o conceito de despacho de potência reativa e fluxo de potência reativa ótimo, por meio de uma abordagem centralizada da rede, utilizando-se o software OpenDSS e MatLab, equipado com Algoritmo Genético (AG) para solucionar o problema de otimização. Para avaliar o desempenho do modelo, foram feitos estudos de caso no sistema IEEE 123 barras e em uma rede real em Alegrete. Os resultados obtidos validam a abordagem proposta, demonstra a aplicabilidade e limitações em casos reais. / The distributed generation in Brazil has increased in the past years, specially in photovoltaic power generation, at the category that Brazilian Electric Regulator ANEEL classifies as "distributed micro-generation", i.e., generation units in which the active power capacity is equal or bellow 75kW and conected on distribution network by the consumers. Despite the traditional problems that might occur due to high penetration of the units, e.g., higher losses and voltage sags and swells, they are conected to the network through an inverter that can be controlled in order to provide or consume reactive power, providing voltage regulation. In that context, considering the use of intelligent inverters that can be remotely operated by a centralized utility operator, this work aims to propose a centralized voltage regulation methodology using distributed micro-generation in distribution networks. The proposed methodology uses the concept of reactive power dispatch and optimal power flow, from a centralized view of the network, using the software MatLab and OpenDSS with Genetic Algorithm to solve the optimization problem. To evaluate the model, simulations were performed with the IEEE 123 bus system and with a real distribution network from the Alegrete city, in the Brazilian state of Rio Grande do Sul. The results show the proposed is valid, despite some limitations on real cases.