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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.
81

[en] OPTIMIZATION OF BATTERY SWAPPING STATIONS WITH BATTERY HETEROGENEITY, CHARGING DEGRADATION AND PV-OPTION / [pt] OTIMIZAÇÃO DE ESTAÇÕES DE TROCA DE BATERIA COM BATERIAS HETEROGÊNEAS, DEGRADAÇÃO NA CARGA E OPÇÃO FOTOVOLTÁICA

NICKOLAS GUELLER ROCHA 27 March 2023 (has links)
[pt] Problemas de emissão de gases de efeito estufa vem sido amplamente discutidos nos últimos anos, uma vez que mais de 70 países já se comprometeram a uma economia neutra em carbono até 2050. A eletrificação dos modais de transporte tem sido ampliadas seguindo essas metas, onde os Veículos Elétricos (VEs) começam a ganhar participação sobre o mercado de Veículos com Motor de Combustão Interna (VMCI) por todo o mundo. Além da particular complexidade na comparação entre VEs e VMCIs, desafios envolvendo a natureza dos VEs e sua integração com as cidades, como a falta de locais públicos para recarga, também são críticos e interferem no seu desenvolvimento. Nesse contexto, este trabalho visa estudar o problema de uma Estação de Troca de Baterias (ETB), uma estrutura onde os usuários de VEs trocam suas baterias descarregadas por outras totalmente ou parcialmente carregadas. No intuito de simular as operações diárias do ETB e o cronograma de carregamento das baterias, um novo modelo de Programação Linear Inteira Mista (PLIM) é proposto, levando em consideração a heterogeneidade da bateria, o uso de geração fotovoltaica (PV) local e a degradação da bateria com base no perfil de carregamento. Uma coleção de métricas de operação do ETB é projetada para avaliar a qualidade da solução do modelo de cronograma proposto. É apresentado um experimento numérico que compreende quatro estudos de caso baseados em dados reais dos sistemas de energia e transporte dos EUA, contendo insights e análises sobre o uso da energia fotovoltaica e da rede, bem como uma comparação financeira do ETB com abordagens de cronograma de benchmarks relacionados, juntamente de sensibilidades no plano de dimensionamento do ETB e atendimento a clientes. / [en] Greenhouse gas emissions-related issues have been extensively discussed in the past years, with over 70 countries already committed to a carbon-neutral economy by 2050. The electrification of transportation modals has increased following these goals, where Electric Vehicles (EVs) are starting to take Internal Combustion Engine Vehicles (ICEV) market share all over the globe. Besides the particular complexity in comparing EVs and ICEVs, challenges involving the nature of EVs and their integration with cities, such as the lack of public locals for charging, are also critical and interfere with their development. In this context, this work aims at studying the problem of a Battery Swapping Station (BSS), a structure where the EVs users swap their depleted batteries for fully or partially charged ones. In order to simulate the BSS daily operations and batteries charging schedule, a novel Mixed Integer Linear Programming (MILP) model is proposed, taking into account battery heterogeneity, the use of local photovoltaic (PV) production and battery degradation based on charging profile. A collection of BSS operation metrics are designed to evaluate the solution quality of the proposed scheduling model. A numerical experiment comprising four case studies based on real data from the US power and transportation systems is presented, with insights and analyses on the PV and grid power use, as well as a BSS financial comparison against close-related benchmark scheduling approaches, together with sensitivities on BSS sizing plan and costumers attendance.
82

ANALYSIS AND MITIGATION OF FREQUENCY DISTURBANCES IN AN ISLANDED MICROGRID

Mondal, Abrez 03 August 2017 (has links)
No description available.
83

DYNAMIC SIMULATION TOOL FOR DISTRIBUTION FEEDERS USING A SPARSE TABLEAU APPROACH

Aravindkumar Rajakumar (17929553) 22 May 2024 (has links)
<p dir="ltr">Distributed energy resources (DERs), such as rooftop solar generation and energy storage systems, are becoming more prevalent in distribution systems. DERs are connected to the distribution system via power electronic converters, introducing faster dynamics in the system. Understanding the system dynamics under a high penetration of inverter-based DERs is critical for power system researchers and practitioners, driving the development of modeling techniques and simulation software. Aiming to reduce computational complexity, existing tools and techniques often employ various approximations. Meanwhile, modern advancements in computational hardware capabilities provide opportunities to include the faster time-scale dynamics. To address this, the primary objective of this thesis is to develop an open-source Python simulation package, Dynamic Simulation using Sparse Tableau Approach in Python, DynaSTPy (pronounced “dynasty”), capable of capturing the dynamics of all components in a distribution feeder. The distribution feeder is modeled as a system of Differential-Algebraic Equations (DAEs). Further, each component in the feeder is modeled based on the Sparse Tableau Approach (STA), which involves the representation of component model equations using sparse matrices, facilitating a systematic procedure to model the components and construct the system DAEs. In sinusoidal steady state, the DAEs can be represented in phasor form, extending the approach to perform power flow analysis of distribution feeders.</p>
84

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.
85

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.
86

Residential Solar Energy Adoption in a Community Context: Perceptions and Characteristics of Potential Adopters in a West Toronto Neighbourhood

Sherk, Theodore January 2012 (has links)
In the summer of 2007, a single neighbourhood in downtown Toronto contributed at least 13 percent of all residential grid???tie solar photovoltaic (PV) systems sold in the Canadian province of Ontario. On average, PV purchaser households produced 37 percent as much electricity as they consumed. This research investigates solar energy adoption in a community case study. Specifically, it investigates why some residents who sign up for a solar resource assessment through a community solar energy initiative (CSEI) decide to purchase, and others decide not to purchase in the short???term. Characteristics and perceptions of potential adopters are analyzed to better understand their motivations and barriers to adoption. Community energy projects became an official public policy goal in Ontario, with the passing of the Green Energy and Green Economy Act in 2009. Approximately 80 percent of Ontario???s anticipated generation capacity will need to be built, replaced or refurbished within 15 years. In this context, the Ontario Ministry of Energy, Ontario Power Authority, and Deloitte (one of Canada???s leading professional services firms), have partnered with a ???green benefit??? fund, the Community Power Fund, to help local community groups access resources to develop and establish renewable energy projects. Understanding solar energy adoption in a community context is therefore important to improve the effectiveness of such policies, including the disbursement of multi???million dollar grant funds. Differences between purchasers and non???purchasers in respect of adoption behaviour were found in this study to cluster around two general themes. The first theme concerns differences in compatibility of both the concept of solar energy systems, and their physical attributes, with characteristics of potential adopter households. Some compatibility issues are straightforward, e.g. availability of roof space with a southern orientation. Others are more complex, involving several interrelated perceptual and socio???demographic factors. For instance, while both purchasers and non???purchasers rated cost as a very important barrier, purchasers rated the motivation of solar energy systems to reduce climate change higher relative to the barrier of high financial costs than did non???purchasers. Purchasers were also more likely to possess a graduate degree, while non???purchasers were more likely to hold a professional degree. The second general theme relates to potential adopters??? trust and stake in the ability of the community???based initiative to reduce barriers in the adoption process. Since two types of solar energy systems are considered in the case study???PV and thermal (hot water)???differences are explored between each of three respondent groups: solar PV purchasers, solar hot water (SHW) purchasers, and non???purchasers. iv Surveys were used to gather data on adopter perceptions and characteristics. A participatory research design helped identify the research topic. Two main bodies of literature???community???based social marketing (CBSM) and diffusion of innovations theory???were drawn upon to conceptualize the adoption process and interpret the survey findings. These include five models of human behaviour that can be used to guide the design of CBSM campaigns. Diffusion theory was used as a basis for discussing ???perceived innovation attributes???. The study takes an integrated approach by considering both social and technical aspects of solar energy adoption, together with the issues of fuel substitution and household electricity demand.

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