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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.
41

[en] DEMAND CHARGE FOR LOW VOLTAGE CONSUMERS IN BRAZIL: IMPACTS AND CRITICAL ANALYSIS / [pt] TARIFA BINÔMIA PARA CONSUMIDORES DE BAIXA TENSÃO NO BRASIL: IMPACTOS E ANÁLISE CRÍTICA

FLÁVIA SILVEIRA DE AZEVEDO 20 February 2019 (has links)
[pt] Nos últimos anos tem se verificado um papel mais ativo do pequeno consumidor com relação ao uso da energia elétrica. O acesso mais facilitado às tecnologias de geração distribuída, principalmente produção local fotovoltaica em telhados de residências e também às novas gerações de medidores inteligentes, despertou o interesse de pequenos consumidores para gerar sua própria energia, reduzindo sua fatura com a distribuidora e também sua dependência da rede de distribuição. Nesse contexto, o objetivo da dissertação é avaliar, com base em medições inteligentes reais, o impacto nas faturas de consumidores residenciais causado pela introdução de uma Tarifa de Uso do Sistema de Distribuição, em reais/quilowatt, aplicada sobre a demanda máxima registrada. A opção pelo tema buscou atender lacunas na bibliografia nacional por tratar-se de um assunto inovador, não só no Brasil, e que está sendo estudado em diversos países no mundo simultaneamente. A metodologia pode ser dividida, basicamente, em quatro fases: (i) Apuração da receita de referência; (ii) Cálculo das tarifas de distribuição nas modalidades horária e em reais/quilowatt; (iii) Cálculo e avaliação das receitas obtidas pela aplicação das tarifas às medições dos clusters de estudo; e (iv) Cálculo e avaliação das receitas obtidas pela aplicação das tarifas às medições dos clusters de estudo, considerando geração fotovoltaica distribuída. Os resultados permitiram identificar os perfis de consumo que seriam mais impactados pela introdução de uma tarifação sobre a demanda e também os efeitos resultantes da instalação de painéis solares nas residências, assim demonstrar que essa modalidade de tarifação, ao refletir os custos da atividade de distribuição de energia, propicia estabilidade das tarifas e evita subsídios cruzados. / [en] In recent years there has been a more active role of small consumers in relation to the use of electricity. The easier access to distributed generation technologies, mainly local photovoltaic production in residential roofs and also the new generations of intelligent meters, has brought the interest of small consumers to generate their own energy, reducing their invoice with the distributor and also their dependence on the distribution network. In this context, the objective of this dissertation is to evaluate, based on real smart measurements, the impact on the invoices of residential customers caused by the introduction of a demand charge, in real/kilowatt, applied on the registered maximum demand. The option for the theme sought to address gaps in the national bibliography because it is an innovative subject, not only in Brazil, and which is being studied in several countries simultaneously. The methodology can be divided into basically four phases: (i) Calculation of the reference revenue; (ii) Calculation of distribution tariffs: hourly and based in real/kilowatt; (iii) Calculation and evaluation of the revenues obtained by applying the tariffs to the measurements from the clusters to be studied; and (iv) Calculation and evaluation of the revenues obtained by applying the tariffs to the measurements from the clusters to be studied, considering distributed photovoltaic generation. The results allowed to identify the consumption profiles, whether they would be more impacted by the introduction of a demand charge and the impacts caused by the installation of solar panels by the residences as well as demonstrating that this type of charge, reflecting the costs of distribution, provides tariff stability and avoids cross subsidies.
42

Méthodes d'optimisation et de gestion de l’énergie dans les réseaux intelligents "Smart Grids" / Optimization methods and energy management in "smart grids"

Melhem, Fady Y. 12 July 2018 (has links)
Les réseaux électriques actuels connaîtront un profond changement dans les années à venir. La nouvelle génération est le Smart Grid (SG) ou le réseau électrique intelligent qui se caractérise par une couche d'information et de communication qui permet aux différents composants du réseau de communiquer. Il doit considérer tous les aspects du réseau électrique, le rendant plus intelligent et flexible. Cette notion est présentée comme une réponse à l'évolution du marché de l'électricité, visant à gérer l’augmentation de la demande tout en assurant une meilleure qualité de service et plus de sécurité.Premièrement, nous présentons une formulation de programmation linéaire mixte en entier pour optimiser les systèmes de production et de consommation d'énergie dans une maison intelligente avec un déploiement efficace de plusieurs ressources énergétiques distribuées. Ensuite, à travers la conception d'expériences avec la méthode de Taguchi, divers scénarios sont introduits en faisant varier des facteurs significatifs. Par la suite, une technique heuristique est proposée pour résoudre le problème de la gestion de l'énergie résidentielle en trouvant la solution optimale globale pendant plusieurs jours consécutifs avec une réduction significative du temps d'exécution.Deuxièmement, un modèle de gestion de l'énergie est assuré grâce à des modèles mathématiques pour optimiser l’utilisation du réseau, des ressources énergétiques renouvelables, des véhicules électriques et de la batterie, ainsi que pour différents types d'appareils thermiques et électriques. Une méthode de solution exacte est mise en œuvre pour réduire le coût de l'électricité dans une maison intelligente et pour trouver des modes de fonctionnement de différentes charges. Ensuite, un algorithme d'optimisation math-heuristique est proposé pour résoudre le problème avec un temps de simulation étendu.Enfin, nous étudions le problème de gestion de l'énergie dans un microréseau constitué de plusieurs maisons intelligentes. Chacune d'elles dépose de ressources énergétiques renouvelables, d’un véhicule électrique et d’appareils intelligents. Les ressources d'énergie renouvelable injectent l’excès de l'énergie dans un système de stockage d'énergie partagé. Un modèle mathématique linéaire mixte en entier pour la gestion d'énergie est proposé pour réduire le coût total de fonctionnement du microréseau. Des comparaisons avec des scénarios conventionnels où chaque maison intelligente possède son propre système de stockage d'énergie sont effectuées pour démontrer l’efficacité de la démarche proposée. / The current electricity grids will experience a profound change in the coming years. The new generation is the Smart Grid (SG) which is characterized by information and communication layer enabling the communication between the different components of the grid. It needs to consider all sides of power grid, making it more intelligent and flexible. This notion is presented as an answer to changes in the electricity market, aiming to manage the increased demand while ensuring a better quality of service and more safety.First, we present a mixed integer linear programming formulation to optimize the energy production and consumption systems in a smart home with an effective deployment of several distributed energy resources. Then through the design of experiments with the Taguchi method, diverse scenarios are introduced by varying significant factors. Afterward, a heuristic technique is proposed to solve the problem of residential energy management by finding the global optimum solution for many consecutive days with significant reduction of execution time.Second, an energy management model is proposed thanks to mathematical models to optimize the grid, renewable energy resources, battery and electric vehicles are presented as well as for different type of thermal and electrical appliances. An exact solution method is implemented to reduce the electricity cost in a smart home and find out operation modes of different loads. Then a math-heuristic optimization algorithm is proposed to solve the problem with extended simulation time horizon.Finally, we study a microgrid energy management problem which comprises multiple smart homes. Each of them owns renewable energy resources, one electric vehicle and smart appliances. The renewable energy resources inject the excess energy in the shared energy storage system. An optimized energy management model using mixed integer linear programming is proposed to reduce the total electricity cost in the microgrid. Comparisons with conventional scenarios where each smart home has its individual small energy storage system without sharing energy with their neighbors are done to ensure that the proposed formulation is well efficient.
43

Towards the design of flexibility management in smart grids : A techno-institutional perspective

Eid, Cherrelle January 2017 (has links)
The European policy focus on smart grids implies their development as an indispensable part of the future power system. However, the definition of a smart grid is broad and vague, and the actual implementation of a smart grid can differ significantly, depending on the stakeholders involved.This work aims to inform policy makers, the electricity industry and researchers about stakeholder interests and the technical complexities involved by presenting smart grids via a techno-institutional framework. This framework takes account of the technical nature of the electricity transport and supply service as well as the institutional nature of electricity markets, stakeholder perspectives and sector regulation. In addition, this work presents potential revenues resulting from flexibility management in smart grids and proposes a way forward for smart grids and flexibility management in Europe. / <p>QC 20170925</p>
44

ANALYSIS AND MITIGATION OF FREQUENCY DISTURBANCES IN AN ISLANDED MICROGRID

Mondal, Abrez 03 August 2017 (has links)
No description available.
45

Transient And Distributed Algorithms To Improve Islanding Detection Capability Of Inverter Based Distributed Generation

Al Hosani, Mohamed 01 January 2013 (has links)
Recently, a lot of research work has been dedicated toward enhancing performance, reliability and integrity of distributed energy resources that are integrated into distribution networks. The problem of islanding detection and islanding prevention (i.e. anti-islanding) has stimulated a lot of research due to its role in severely compromising the safety of working personnel and resulting in equipment damages. Various Islanding Detection Methods (IDMs) have been developed within the last ten years in anticipation of the tremendous increase in the penetration of Distributed Generation (DG) in distribution system. This work proposes new IDMs that rely on transient and distributed behaviors to improve integrity and performance of DGs while maintaining multi-DG islanding detection capability. In this thesis, the following questions have been addressed: How to utilize the transient behavior arising from an islanding condition to improve detectability and robust performance of IDMs in a distributive manner? How to reduce the negative stability impact of the well-known Sandia Frequency Shift (SFS) IDM while maintaining its islanding detection capability? How to incorporate the perturbations provided by each of DGs in such a way that the negative interference of different IDMs is minimized without the need of any type of communication among the different DGs? It is shown that the proposed techniques are local, scalable and robust against different loading conditions and topology changes. Also, the proposed techniques can successfully distinguish an islanding condition from other disturbances that may occur in power system networks. This work improves the efficiency, reliability and safety of integrated DGs, which presents a necessary advance toward making electric power grids a smart grid.
46

能源管理服務業營運模式與智慧財產佈局策略之分析 / The analysis of business model and intellectual property strategy of energy service companies (ESCO)

陳志承, Chen, Charlie, Chih-Chen, Unknown Date (has links)
由於石化能源的蘊藏量有限,各國政府目前以能源的安全供給與環保的使用做為主要的能源政策,經過各國公部門與私部門多年來的努力,許多替代能源的技術雖然開始商品化,但實際上對於傳統石化能源依賴度的減少,仍舊有限。反觀節能技術雖然表面上不如屬於”開源”概念的再生能源響亮,但技術的成熟度與產業化對於減少石化能源依賴的貢獻度並不亞於開源的效果,尤其許多發展中的國家短期內勢必無法負擔新的再生能源技術所要付出的昂貴能源費用,能源管理服務業所能提供的節能效果,可以同時解決能源效率低落所造成的浪費以及環境的衝擊。 而能源管理服務業重點在於節能,歐洲與日本市場無論是民眾或是政府在開發替代能源與節約能源的議題上之成果有目共睹,但反觀耗能最高的美國、發展中的中國,節能議題相對來講更形重要,這與台灣的狀況相當類似,因此本研究期望經由法制政策面、產業面以及智慧財產佈局狀況,探討美國與中國之能源管理服務業之現況,並與台灣本身能源管理服務業之發展做比較,提出能源管理服務業未來發展上的建議。 1. 能源管理服務業不宜將有限資源過分集中於發展太陽能與風力發電技術 2. 以美國市場為鏡,以中國大陸能源管理市場為目標 3. 積極從事中國大陸能源管理服務業相關技術之專利佈局 4. ”中央能源管理服務系統”概念的導入-節能減排的技術與服務的創新 5. 發展能源管理服務業住宅之應用 6. 創新的融資模式 7. 人員的培訓與教育 / Due to the limited deposits of fusil energy, the safety and environment protection of energy use ate the most two crucial issues among the countries. After decades of development, alternative energy commercialization successfully started in developed countries. Nevertheless, it’s still not material enough comparing to the energy consumption now days. However, the effect of the energy efficiency technologies is far more practical for developing countries that do not have enough budget for alternative renewable energy research and development. With effective energy management, the Energy Service Companies (ESCOs) can reduce significantly the waste of energy and the influence to the environment while mitigate the impact of the economical growth of emerging countries. ESCOs profit from the energy conservation of their clients by enhance the energy efficiency in various categories including utilities, government, industrial and commercial sectors. According to present study, European countries and Japan in Asia have already developed outstanding environmental friendly policies both in public and private sectors. On the other hand, highly energy consumption country like United States and rapidly growing China just started to deal with this global warming problem and hopefully can still maintain the economy growth at the same time. Undoubtedly, we face the same issue here in Taiwan. As a result, this study is trying to gather and analyze information about ESCO industry in United States, China and Taiwan from three aspects, governmental policies, industry environment and intellectual property strategies to conclude as well as raise opinion and suggestion about the future development of ESCOs. This study concludes in following opinion and suggestion, 1. ESCOs shouldn’t emphasize all their resources to conduct Solar and Wind power technologies instead of energy efficiency technologies. 2. Learn the track of ESCOs in United States and focus on the market in China. 3. Aggressively develop intellectual property strategies about ESCO related subjects in China. 4. Introduce the concept of “Centralized Energy Management System” and encourage innovation of law carbon discharge and high efficiency technologies. 5. Develop ESCO model in residential application. 6. Develop creative fund raising tools for ESCOs. 7. Invest in education and training program related to ESCO industry.

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