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1
Trivedi, Manas. "Multi-objective generation scheduling with hybrid energy resources." Connect to this title online, 2007. http://etd.lib.clemson.edu/documents/1202498690/.
Повний текст джерела
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Abdallah, Ibrahim. "Event-driven hybrid bond graph : Application : hybrid renewable energy system for hydrogen production and storage." Thesis, Lille 1, 2017. http://www.theses.fr/2017LIL10104/document.
Повний текст джерелаАнотація:
Ce travail de thèse constitue une contribution à la modélisation et au diagnostic des systèmes multi-domaines à commutation (hybrides). Il est appliqué à la supervision des systèmes multi-sources d’énergie propre où l’hydrogène est utilisé comme moyen de stockage. Un tel système associe des composantes énergétiques de nature différente et fait l’objet de commutations produites par la connexion et déconnexion d’un ou plusieurs composants. Ces commutations génèrent différents modes de fonctionnement et sont liées à l’intermittence des sources primaires, aux capacités de stockage et à la disponibilité opérationnelle des ressources matérielles qui constituent le système. La présence de ces commutations engendre une dynamique variable qui est classiquement difficile à exprimer mathématiquement sans exploiter tous les modes. Ces difficultés de modélisation se propagent pour affecter toutes les tâches dépendantes du modèle comme le diagnostic et la gestion de modes de fonctionnement. Pour résoudre ces problématiques, un nouvel outil, Bond Graph Hybride piloté par événements, a été développé. Entièrement graphique, ce formalisme permet une modélisation interdisciplinaire globale du système. En séparant la dynamique continue gérée par le Bond Graph Hybride des états discrets modélisés par un automate intégré, l’approche proposée simplifie la gestion des modes de fonctionnement. Le modèle issu de cette méthodologie est également bien adapté au diagnostic robuste, réalisable sans recourir aux équations analytiques. Associée au diagnostic robuste, cette gestion des modes permet l’implémentation de stratégies de reconfiguration et de protection en présence de défaillancesThis research work constitutes a general contribution towards a simpler modelling and diagnosis of the multidisciplinary hybrid systems. Hybrid renewable energy systems where hydrogen is used to store the surplus of the power fits perfectly under this description. Such system gathers different energetic components that are needed to be connected or disconnected according to different operating conditions. These different switching configurations generate different operating modes and depend on the intermittency of the primary sources, the storage capacities and the operational availability of the different hardwares that constitute the system. The switching behaviour engenders a variable dynamic which is hard to be expressed mathematically without investigating all the operating modes. This modelling difficulty is transmitted to affect all the model-based tasks such as the diagnosis and the operating mode management. To solve this problematic, a new modelling tool, called event-driven hybrid bond graph, is developed. Entirely graphic, this formalism allows a multidisciplinary global modelling for all the operating modes at once. By separating the continuous dynamic driven by the bond graph, from the discrete states handled by an integrated automaton, this approach simplifies the management of the operating modes. The model issued using this methodology is also well-adapted to perform a robust diagnosis which is achievable without referring back to the analytical description of the model. The operating mode management, when associated with the on-line diagnosis, allows the implementation of reconfiguration strategies and protection protocols when faults are detected
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Somayajula, Deepak. "Control aspects of a double-input buckboost power electronic converter." Diss., Rolla, Mo. : Missouri University of Science and Technology, 2009. http://scholarsmine.mst.edu/thesis/pdf/Somayajula_2009_09007dcc8070c9e2.pdf.
Повний текст джерелаАнотація:
Thesis (M.S.)--Missouri University of Science and Technology, 2009.Vita. The entire thesis text is included in file. Title from title screen of thesis/dissertation PDF file (viewed November 17, 2009) Includes bibliographical references (p. 67-70).
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El, Tawil Tony. "On sizing and control of a renewables-based hybrid power supply system for stand-alone applications in an island context." Thesis, Brest, 2018. http://www.theses.fr/2018BRES0003/document.
Повний текст джерелаАнотація:
L’objectif de cette thèse est de dimensionner et régler un système hybride de production d’énergie pour un site isolé de type insulaire, basé sur des énergies renouvelables marines. De manière préliminaire divers systèmes de production d’énergie renouvelable marine ont d’abord été étudiés et comparés de manière qualitative à des systèmes de production d’énergie classiques. Plusieurs types de système de stockage d’énergie ont également été étudiés, comparés et évalués dans le cas du site considéré. Cette analyse préliminaire a été étendue aux différents types de transmissions d’énergie offshore et de méthodes de réglage des convertisseurs associés aux sources renouvelables. A partir de l’étude des caractéristiques du site et de l’analyse statistique des ressources renouvelables (vents, courants marins) une méthode de dimensionnement des éléments du système de production est présentée, dans l’objectif de minimiser les émissions de CO2 et le coût du système sur son cycle de vie. Pour cela, une solution de gestion de la puissance basée sur la logique floue est proposée pour le type de site considéré et comparée à une solution plus classique basée sur des règles logiques. Pour finir, une étude détaillée des différentes méthodes de réglage du système hybride côté réseau est présentée. Trois niveaux de réglage sont considérés : réglage d’une source unique, réglage d’une ferme de plusieurs sources et réglage global du système hybride. Plusieurs modes de réglage sont considérés pour chaque niveauThis PhD thesis models a renewable-based hybrid power supply system applied in an islanded context and investigates sizing and regulation strategies of such a hybrid system. First, various marine energy production technologies were reviewed and compared to common renewable resources. As well, various energy storage technologies were reviewed, compared, and evaluated to fit the chosen site characteristics. A brief investigation on offshore energy transmission and inverter regulations methods is presented. Then, a study of the site characteristics, and the availability of the different renewable energy resources in the area are presented. This energy study constitutes the basis of the proposed system sizing method, where minimizing the cost and the CO2 emissions are considered as the main objectives. Furthermore, a fuzzy logic power management approach is proposed for the islanded microgrid. Finally, a detailed study of the system components grid-side inverter regulation is presented. Three regulation levels were investigated: the single inverter, the renewable farm, and the hybrid system. In this context, different regulation strategies are considered at each level
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Herrera, Santisbon Eunice. "Production-consumption system coordination by hybrid predictive approaches : application to a solar cooling system for buildings." Thesis, CentraleSupélec, 2015. http://www.theses.fr/2015SUPL0006/document.
Повний текст джерелаАнотація:
Garantir le confort thermique des bâtiments est directement lié à la consommation d'énergie. Dans les zones tropicales, les systèmes de refroidissement représentent l'un des postes les plus gourmands en énergie. Afin de réduire la consommation d'énergie mondiale, il est primordial d'améliorer l'efficacité de ces systèmes ou bien de développer de nouvelles méthodes de production de froid. Une installation de refroidissement solaire basé sur le cycle à absorption est une alternative pour réduire les émissions de gaz à effet de serre et la consommation d'électricité. Contrairement aux systèmes classiques de refroidissement à compression mécanique, la production de froid par absorption est un système complexe composé de plusieurs composants comme des panneaux solaires, un ballon de stockage, une tour de refroidissement et une machine à absorption. Outre le dimensionnement des composants, ce système complexe nécessite des actions de contrôle pour être efficace parce que la coordination entre le stockage d'eau chaude, la production et la consommation du froid est nécessaire. Le but de cette thèse est de proposer une structure producteur-consommateur d'énergie basée sur la commande prédictive (MPC). Le système de refroidissement par absorption solaire est considéré comme faisant partie de ce système de production-consommation d'énergie, le système de stockage d'eau chaude est le producteur et la machine à absorption qui distribue de l'eau froide au bâtiment est l'un des consommateurs. Pour que la structure de commande soit modulaire, la coordination entre les sous-systèmes est réalisée en utilisant une approche de partitionnement où des contrôleurs prédictifs locaux sont conçus pour chacun des sous-systèmes. Les contrôleurs des consommateurs calculent un ensemble de profils de demande d'énergie. Ces profils sont ensuite envoyés au contrôleur du producteur qui sélectionne le profil qui minimise le coût global. Dans une première partie, l'approche proposée est testée sur un modèle linéaire simplifié composé d'un producteur et plusieurs consommateurs. Dans une deuxième partie, un cas plus complexe est étudié. Un modèle simplifié d'un système de refroidissement à absorption est évaluée en utilisant l'outil de simulation TRNSYS. Le modèle de production n'est plus linéaire, il est décrit par un modèle non linéaire hybride qui augmente la complexité du problème d'optimisation. Les résultats des simulations montrent que la sous-optimalité induite par la méthode est faible. De plus, la performance de l'approche atteint les objectifs de commande tout en respectant les contraintesTo guarantee thermal comfort in buildings is directly related to energy consumption. In tropical climates, cooling systems for buildings represent one of the largest energy consumers. Therefore, as energy consumption is a major concern around the world, it is important to improve the systems efficiency or seeking new methods of cooling production. A solar cooling installation based on the absorption cycle is an alternative to mitigate greenhouse gas emissions and electricity consumption. In contrast to conventional vapor-compression based cooling systems, the absorption cooling production involves a complex system composed of several components as collector panel, storage tank, cooling tower and absorption chiller. Besides the sizing of the components, this complex system requires control actions to be efficient as a coordination between hot water storage, cooling water production and consumption is necessary. The aim of this research is to propose a management approach for a production-consumption energy system based on Model Predictive Control (MPC). The solar absorption cooling system is seen as part of this production-consumption energy system where the hot water storage system is the producer and the chiller-building system is one of the consumers. In order to provide modularity to the control structure, the coordination between the subsystems is achieved by using a partitioning approach where local predictive controllers are developed for each of the subsystems. The consumer controllers compute a set of energy demand profiles sent to the producer controller which selects the profile that better minimize the global optimization cost. In a first part, the proposed approach is tested on a simplified linear model composed of one producer and several consumers. In a second part, a more complex case is studied. A simplified model of an absorption cooling system is evaluated using the simulation tool TRNSYS. The producer model is no longer linear, instead it is described by a nonlinear hybrid model which increases the complexity of the optimization problem. The simulations results show that the suboptimality induced by the method is low and the control strategy fulfills the objectives and constraints while giving good performances
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Ben, Jemaa Abdelhak. "Coopération méta heuristique et logique floue pour le dimensionnement d'une installation hybride." Thesis, Reims, 2015. http://www.theses.fr/2015REIMS009/document.
Повний текст джерелаАнотація:
Cette thèse propose la méthodologie de dimensionnement optimal pour optimiser la configuration de système d'énergie hybride. Pour cela, nous utilisons une approche pour la génération de base de règles floues et une optimisation automatiques au moyen d'algorithme génétique et d'un PSO adaptés avec le floue. Ces algorithmes nous permet d'obtenir le nombre optimal de panneaux photovoltaïques, d'éoliennes et des batteries, minimisant le coût total du système et garantissant la disponibilité permanente de l'électricité pour couvrir les besoins énergétiques. L'historique horaire de vitesse du vent, d’ensoleillement, sont utilisés pour modéliser la production des éoliennes, la production photovoltaïque et de charge. Le coût total est la fonction objective et la taille technique est une contrainteThis thesis proposes the optimum sizing methodology to optimize the configuration of hybrid energy system. For this, we use an approach for automatic fuzzy rule base generation and optimization by means of Fuzzy-Adaptive Genetic Algorithm and fuzzy adaptive PSO. This Algorithms allows us to obtain the optimal number of photovoltaic panels, wind turbines and storages units, ensuring the minimal global high efficiency system total cost and guaranteeing the permanent availability of energy to cover the load energy requirements. Historical hourly wind speed, solar irradiance and load data are used to stochastically model the wind turbines, photovoltaic generation and load. The total cost is the objective function and the technical size is a constraint
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Saidi, Majdi. "Contribution à l'optimisation des systèmes hybrides de production énergétique à base de sources renouvelables." Electronic Thesis or Diss., Aix-Marseille, 2021. http://www.theses.fr/2021AIXM0627.
Повний текст джерелаАнотація:
Cette thèse est une contribution à la conception optimale des systèmes hybrides pour la production énergétique. Les travaux proposés sont organisés en trois parties. La première partie consiste à étudier la possibilité d’intégrer des sous-réseaux constitués d’un ensemble de producteur-exploitant connectés au réseau principal. Le but est de renforcer la décentralisation de la production énergétique en tenant compte des besoins spécifiques et des disponibles de source renouvelable. Pour ce faire, l’approche consiste à optimiser le coût de l’installation, pour le producteur-exploitant, et les taux des subventions, assurées par l’état-soutien, tout en évitant la spéculation financière. La deuxième partie traite du problème de dimensionnement des systèmes hybrides par adaptation optimale de la charge, et l’approche est effectuée en deux parties. Une première partie consiste à modéliser la charge en tenant compte des contraintes spécifiques à l’exploitation. Ensuite, lors de la deuxième partie, une optimisation de la structure est effectuée en fonction du disponible énergétique. La troisième partie est consacrée au cas spécifique d’une application en nomade. Tout d’abord, il s’agit de déterminer les différentes contraintes caractéristiques à ce type d’application (sécurité énergétique, coût de la conception, etc.) et de définir les différents problèmes d’optimisation associés aux objectifs spécifiques. Ensuite, une étude de cas exprimée comme un problème d’optimisation de nature multi-objectif est énoncée. Finalement, des solutions optimales sont identifiées à travers des outils d’intelligence artificielle et de considérations liées à l’applicationThis thesis is a contribution to the optimal design of hybrid systems for energy production. The proposed work is organised in three parts. The first part is dedicated to an energy analysis at the level of the national electricity grid. The aim is to study the possibility of integrating sub-grids consisting of a set of producer-operators connected to the main grid. The aim is to strengthen the decentralisation of energy production, taking into account the specific needs and availability of renewable sources. To achieve this, the approach is to optimise the cost of the installation for the producer-operator and the subsidy rates provided by the supporting state, while avoiding financial speculation. The second part deals with the problem of sizing hybrid systems by optimal load adaptation, and the approach is carried out in two parts. In the first part, the load is modelled taking into account the specific constraints of the operation. Then, in the second part, an optimisation of the structure is carried out according to the available energy. To illustrate the relevance of the approach, an application to a concrete case of a company is performed. The third part is devoted to the specific case of a nomadic application. First, the different constraints characteristic of this type of application (energy security, design cost, etc.) are determined and the different optimisation problems associated with the specific objectives are defined. Then, a case study expressed as an optimisation problem of a multi-objective nature is stated. Finally, optimal solutions are identified through artificial intelligence tools and application
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Martínez, Díaz Maria del Mar. "Stand-alone hybrid renewable energy systems (HRES)." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/457978.
Повний текст джерелаАнотація:
End of Energy Poverty and achieving Sustainable Energy for all by 2030 is a universal challenge. 1.3 billion people without energy access and 2.8 billion people using unsustainable solid fuel for cooking and heating are global challenges for human and societal sustainable development. Nearly $1 trillion of investment is expected in the Sustainable Energy for All (SE4ALL) scenario to achieve universal energy access in 2030. Around 60% of investments will be in isolated off-grid and mini-grid systems with the relevant goal of duplicating the renewable energy sources in the energy mix.
Access to innovation trends in renewable energy off-grid would benefit future installations. This work brings to light the recent years research contributions in Hybrid Renewable Energy Systems (HRES) and related aspects that would benefit these required investments in isolated off-grid and mini-grid systems. An overview on the thematic focus of research in Hybrid Renewable Energy Systems (HRES) in the last decade, period 2005 - 2015, is provided. This review covers multiple key aspects of HRES as the main focus of the research (technical, economical, environmental, financial, etc.); the design of the system (type of load, energy sources, storage, availability of meteorology data, etc.); different optimization criteria and objective function; software and modelling tools; and the type of application and country among others. A methodology for searching, identifying and categorizing the innovations related to HRES is proposed. Applying this methodology during this PhD work results in a primary database with a categorized bibliography including nearly 400 entries.
Currently system design is mainly technical driven with economic feasibility analysis regarding the energy cost. As for environmental aspects, the beneficial impacts of renewable energy are hardly introduced as an economical value that is so far the most important decision-making criteria. Regarding decision-making tools, the most currently used optimization algorithms and software tools for the design of HRES is HOMER and a case study for understanding is proposed. Following the analysis of most popular and relevant criteria, an easy to use guideline is proposed encouraging decision-making for more sustainable energy access.
There are untapped research opportunities for HRES in multi-disciplinary thematic areas. The analysis of innovations regarding the system design for Hybrid Renewable Energy Systems (HRES) have identified potential for research community aligned with the trends to integrate the value chain and foster innovative business models and sustainable energy markets.
After the analysis of those different focus that goes from technical and economical, to environmental, regulatory or policy aspects, an integrated value chain for HRES systems is defined.
Knowledge, methodologies & tools are provided in this PhD work for more stand-alone hybrid systems creating value for more of the stakeholders involved. After reviewing the latest innovations in HRES per thematic focus, an integrated value chain for those systems has been proposed and multidisciplinary research opportunities have been identified. Identifying the need to include the environmental aspects in early stages of the decision-making has lead to propose an easy to use guideline integrating most relevant criteria for the design of stand-alone renewable power systems. Finally, the research opportunities identified and the untapped potential of transferring latest innovations have result in the creation of the website ElectrifyMe (www.electrifyme.org) to enable valuable international networking contacts among researchers and encouraging multi-disciplinary research. "Knowledge, methodologies & tools" are powerful contributions by research community and innovators to foster more sustainable energy for all.El fi de la pobresa energètica i l'assoliment d'energia sostenible per a tothom l'any 2030 és un repte universal. 1,3 mil milions de persones sense accés a l'energia i 2,8 mil milions de persones que utilitzen combustible sòlid insostenible per cuinar i escalfar són desafiaments globals pel desenvolupament humà sostenible i social. S'espera una inversió aproximada de $1 trilió en l'energia sostenible per a tots (SE4ALL) per aconseguir l'accés universal a l'energia en 2030. Al voltant del 60 % de les inversions seran en sistemes off-grid i mini-grid, amb la corresponent meta de duplicar les fonts d'energia renovables en el mix energétic. En aquesta tesis es facilita una visió general sobre els àmbits temàtics de la recerca en Hybrid Renewable Energy Systems (HRES) en l'última dècada, període 2005-2015. Aquesta revisió es refereix a diversos aspectes clau deis HRES com: el focus principal de la investigació (tècnics, econòmics, ambientals, financers, etc.); el disseny del sistema (tipus de carrega, fonts d'energia, l'emmagatzematge, la disponibilitat de dades de meteorologia, etc.); diferents criteris d'optimització i funció objectiu; programari de modelatge eines; i el tipus d'aplicació i el país, entre d'altres. Es proposa una metodologia per buscar, identificar i categoritzar les innovacions relacionades amb els HRES. L'aplicació d'aquesta metodologia durant aquest treball de doctorat proporciona una base de dades primaria amb una bibliografia classificada incloent prop de 400 entrades. Actualment el disseny dels sistemes incorporen criteris tècnics amb anàlisi de viabilitat econòmica sobre el cost de l'energia. Pel que fa a les eines de presa de decisions, el métode d'optimització més utilitzats en l'actualitat pel disseny de HRES és HOMER, i es proposa un estudi de cas per a la comprensió deis criteris de disseny. Després de l'anàlisi de la majoria deis valors més habituals i rellevants, es proposa una senzilla guia per la presa de decisions per a l'accés a l'energia més sostenible. Després de compartir innovacions i proporcionar metodologies i eines, facilitar la creació de xarxes entre els investigadors ha demostrat ser una poderosa acció per promoure recerca sense explotar amb equips multidisciplinaris i internacionals. La pàgina web ElectrifyMe (www .electrifyme .org) ha estat creada amb la finalitat de facilitar a la comunitat d'investigació descobrir les innovacions i compartir projectes . Coneixements, metodologies i eines es proporcionen en aquest treball de doctorat per afavorir la creació de valor als sistemes aïllats híbrids renovables (stand-alone HRES) pels actors involucrats. Després de revisar les últimes innovacions en la introducció de renovables en sistemes aïllats en diferent enfoc temàtic, s'han estat identificat oportunitats de recerca multidisciplinars i s'ha proposat una cadena de valor integrada per aquests sistemes. La identificació de la necessitat d'incloure els aspectes ambientals en les primeres etapes de la presa de decisions ha portat a proposar una guia fàcil per utilitzar la integració de criteris més rellevants pel disseny de sistemes d'energia renovables independents. Finalment, tes oportunitats de recerca identificades i el potencial sense explotar de transferir les darreres innovacions tenen com a resultat la creació de la pàgina web ElectrifyMe (www.electrifyme.org) per promoure contactes i col·laboracions de xarxes internacionals entre investigadors i el foment de la investigació multidisciplinar. "El coneixement, les metodologies i les eines són poderoses contribucions de la comunitat de recerca per assolir un accés sostenible a l'energia per tots"
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Das, Debosmita. "Advanced power electronics for hybrid energy systems." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1412940298.
Повний текст джерела
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Rae, Callum. "Variable energy pricing in stand alone community hybrid energy systems." Thesis, University of Strathclyde, 2016. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=27096.
Повний текст джерелаАнотація:
Satisfying the demand for a more efficient and sustainable energy supply model has presented a new challenge for the energy industry. It has also created an opportunity for alternative and renewable sources of energy generation, which has led to a significant increase in the deployment of renewable technologies in many countries. Recent years have also seen these technologies deployed at a community scale, with remote and isolated communities in particular being regarded as ideal locations. Such systems are capable of providing increasingly viable, standalone alternatives to the centralised energy supply model. This thesis investigates the extent to which the viability of these stand-alone hybrid energy systems could be further improved by implementing domestic demand response, promoted via variable domestic energy pricing. A high resolution,disaggregated model of domestic energy demand at the community level is then developed, supported by the findings of a targeted consumer attitudes survey. This model is combined with a series of demand response algorithms which replicate the response of domestic consumers to energy price variation. Three variable pricing approaches are then applied to the model under a range of conditions, and the impacts examined from both a community-wide and household level perspective. The thesis demonstrates the relevance and potential of stand-alone hybrid applications and the remote/isolated communities in which they are typically deployed. The results find variable domestic energy pricing based on renewable energy supply to be capable of achieving modest yet significant levels of demand response under a broad range of conditions (83% of the scenarios modelled).Further sensitivity analysis shows the pricing strategies to be resilient to changes in supply conditions, thereby illustrating the broad ranging potential of such an approach. However, susceptibility to free-rider behaviour and insensitivity to household elasticity levels suggest the need for additional/supplementary forms of financial incentivisation.
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Kusakana, Kanzumba. "Optimal operation control of hybrid renewable energy systems." Thesis, Bloemfontein: Central University of Technology, Free State, 2014. http://hdl.handle.net/11462/670.
Повний текст джерелаАнотація:
Thesis (D. Tech. (Electrical Engineering)) -- Central University of Technology, Free State, 2014For a sustainable and clean electricity production in isolated rural areas, renewable energies appear to be the most suitable and usable supply options. Apart from all being renewable and sustainable, each of the renewable energy sources has its specific characteristics and advantages that make it well suited for specific applications and locations. Solar photovoltaic and wind turbines are well established and are currently the mostly used renewable energy sources for electricity generation in small-scale rural applications. However, for areas in which adequate water resources are available, micro-hydro is the best supply option compared to other renewable resources in terms of cost of energy produced. Apart from being capital-cost-intensive, the other main disadvantages of the renewable energy technologies are their resource-dependent output powers and their strong reliance on weather and climatic conditions. Therefore, they cannot continuously match the fluctuating load energy requirements each and every time. Standalone diesel generators, on the other hand, have low initial capital costs and can generate electricity on demand, but their operation and maintenance costs are very high, especially when they run at partial loads. In order for the renewable sources to respond reliably to the load energy requirements, they can be combined in a hybrid energy system with back-up diesel generator and energy storage systems. The most important feature of such a hybrid system is to generate energy at any time by optimally using all available energy sources. The fact that the renewable resources available at a given site are a function of the season of the year implies that the fraction of the energy provided to the load is not constant. This means that for hybrid systems comprising diesel generator, renewable sources and battery storage in their architecture, the renewable energy fraction and the energy storage capacity are projected to have a significant impact on the diesel generator fuel consumption, depending on the complex interaction between the daily variation of renewable resources and the non-linear load demand. V This was the context on which this research was based, aiming to develop a tool to minimize the daily operation costs of standalone hybrid systems. However, the complexity of this problem is of an extremely high mathematical degree due to the non-linearity of the load demand as well as the non-linearity of the renewable resources profiles. Unlike the algorithms already developed, the objective was to develop a tool that could minimize the diesel generator control variables while maximizing the hydro, wind, solar and battery control variables resulting in saving fuel and operation costs. An innovative and powerful optimization model was then developed capable of efficiently dealing with these types of problems. The hybrid system optimal operation control model has been simulated using fmincon interior-point in MATLAB. Using realistic and actual data for several case studies, the developed model has been successfully used to analyse the complex interaction between the daily non-linear load, the non-linear renewable resources as well as the battery dynamic, and their impact on the hybrid system’s daily operation cost minimization. The model developed, as well as the solver and algorithm used in this work, have low computational requirements for achieving results within a reasonable time, therefore this can be seen as a faster and more accurate optimization tool.
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Smith, Ian C. S. M. (Ian Charles) Massachusetts Institute of Technology. "Benefits of battery-uItracapacitor hybrid energy storage systems." Thesis, Massachusetts Institute of Technology, 2012. http://hdl.handle.net/1721.1/75685.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2012.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 85-88).
This thesis explores the benefits of battery and battery-ultracapacitor hybrid energy storage systems (ESSs) in pulsed-load applications. It investigates and quantifies the benefits of the hybrid ESS over its battery-only counterparts. The metric for quantifying the benefits is charge efficiency - the amount of energy delivered to the load per unit charge supplied by the battery. The efficiency gain is defined as the difference in charge efficiency between the hybrid and the battery-only ESS. A custom experimental apparatus is designed and built to supply the current control for charging and discharging the batteries, as well as the data acquisition for measuring energy and current output. Experiments are performed on both ESSs under four different pulsed load profiles: 1. 436 ms pulse period, 10% duty cycle, 8 A pulse amplitude 2. 436 ms pulse period, 25% duty cycle, 8 A pulse amplitude 3. 436 ms pulse period, 10% duty cycle, 16 A pulse amplitude 4. 436 ms pulse period, 25% duty cycle, 16 A pulse amplitude Circuit models are created to accurately represent the battery and ultracapacitors. These models are used in simulations of the same test cases from the physical experiments, and efficiency gains are compared. The circuit models differed from the experimentation by less than 1%. Both experimental and simulated data demonstrate significantly increased charge efficiencies of hybrid ESSs over battery-only ESSs, with demonstrated gains between 10% and 36%. These benefits were greatest for the 16 A, 10% duty cycle test case because it combined the highest pulse amplitude and the shortest duty cycle. It is concluded that high-amplitude, low duty cycle, and low period pulsedload profiles yield the highest efficiency gains.
by .Ian C. Smith
S.M.
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Rivano, Giuseppina. "Analysis of offshore hybrid energy systems for improved dispatchability of wave energy." Master's thesis, Alma Mater Studiorum - Università di Bologna, 2019.
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Attualmente è riscontrabile a livello globale un aumento del numero di giacimenti offshore contenenti un piccolo quantitativo di gas a bassa pressione e dunque destinati ad essere avviati alla procedura finale di chiusura. Per eliminare gli elevati costi di trasporto del gas e valorizzare il sito, nasce il concetto di Gas-to-Wire. Esso consiste nella produzione di elettricità attraverso la combustione del gas naturale in sito. Allo stesso tempo, la consapevolezza che le risorse oil & gas sono destinate ad estinguersi con gli anni ha spinto la comunità scientifica a concentrare l’attenzione su nuove forme di energia rinnovabile, come le onde marine. Nonostante ciò, vi sono ancora delle barriere da abbattere legate sia al prezzo di tali tecnologie che alla produzione di energia in modo discontinuo che rende problematica la loro integrazione nella rete elettrica.
Al fine di superare tali problematiche, si è pensato di adottare un sistema ibrido di energia offshore costituito da convertitori di onda e microturbine a gas installate sulla piattaforma presente nel giacimento depleto. Esse forniscono potenza addizionale di bilanciamento sfruttando il concetto di Gas-to-Wire, consentendo una maggiore dispacciabilità dell’energia rinnovabile da onde.
Lo scopo del presente lavoro è quello di analizzare le prestazioni energetiche, economiche e d’impatto ambientale del sistema ibrido di energia offshore. Due differenti siti, Mare del Nord e Mar Adriatico, sono stati presi in considerazione al fine di valutare l’influenza delle diverse condizioni meteo-marine, diversi mercati elettrici di dispacciamento e diversi incentivi fiscali per l’integrazione di energia rinnovabile sulle prestazioni del sistema ibrido di energia offshore. Attraverso l’approccio seguito per il dimensionamento e gestione dei due sistemi ibridi, è stato possibile calcolare gli indicatori tecnici, ambientali ed economici.
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Alawhali, Nasser. "CONTRIBUTIONS TO HYBRID POWER SYSTEMS INCORPORATING RENEWABLES FOR DESALINATION SYSTEMS." UKnowledge, 2018. https://uknowledge.uky.edu/ece_etds/115.
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Renewable energy is one of the most reliable resource that can be used to generate the electricity. It is expected to be the most highly used resource for electricity generation in many countries in the world in the next few decades. Renewable energy resources can be used in several purposes. It can be used for electricity generation, water desalination and mining. Using renewable resources to desalinate the water has several advantages such as reduce the emission, save money and improve the public health. The research described in the thesis focuses on the analysis of using the renewable resources such as solar and wind turbines for desalination plant. The output power from wind turbine is connected through converter and the excess power will be transfer back to the main grid. The photo-voltaic system (PV) is divided into several sections, each section has its own DC-DC converter for maximum power point tracking and a two-level grid connected inverter with different control strategies. The functions of the battery are explored by connecting it to the system in order to prevent possible voltage fluctuations and as a bu er storage in order to eliminate the power mismatch between PV array generation and load demand. Computer models of the system are developed and implemented using the PSCADTM / EMTDCTM software.
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Sachs, Julia [Verfasser]. "Model-Based Optimization of Hybrid Energy Systems / Julia Sachs." Aachen : Shaker, 2016. http://d-nb.info/1101185112/34.
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Natsheh, Emad Maher. "Hybrid power systems energy management based on artificial intelligence." Thesis, Manchester Metropolitan University, 2013. http://e-space.mmu.ac.uk/314015/.
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This thesis presents a novel adaptive scheme for energy management in stand-alone hybrid power systems. The proposed management system is designed to manage the power flow between the hybrid power system and energy storage elements in order to satisfy the load requirements based on artificial neural network (ANN) and fuzzy logic controllers. The neural network controller is employed to achieve the maximum power point (MPP) for different types of photovoltaic (PV) panels, based on Levenberg Marquardt learning algorithm. The statistical analysis of the results indicates that the R2 value for the testing set was 0.99. The advance fuzzy logic controller is developed to distribute the power among the hybrid system and to manage the charge and discharge current flow for performance optimization. The developed management system performance was assessed using a hybrid system comprises PV panels, wind turbine, battery storage, and proton exchange membrane fuel cell (PEMFC). To improve the generating performance of the PEMFC and prolong its life, stack temperature is controlled by a fuzzy logic controller. Moreover, perturb and observe (P&O) algorithm with two different controller techniques - the linear PI and the non-linear passivity-based controller (PBC) - are provided for a comparison with the proposed MPPT controller system. The comparison revealed the robustness of the proposed PV control system for solar irradiance and load resistance changes. Real-time measured parameters and practical load profiles are used as inputs for the developed management system. The proposed model and its control strategy offer a proper tool for optimizing the hybrid power system performance, such as the one used in smart-house applications. The research work also led to a new approach in monitoring PV power stations. The monitoring system enables system degradation early detection by calculating the residual difference between the model predicted and the actual measured power parameters. Measurements were taken over 21 month’s period; using hourly average irradiance and cell temperature. Good agreement was achieved between the theoretical simulation and the real time measurement taken the online grid connected solar power plant.
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He, Yiou. "The assessment of battery-ultracapacitor hybrid energy storage systems." Thesis, Massachusetts Institute of Technology, 2014. http://hdl.handle.net/1721.1/91088.
Повний текст джерелаАнотація:
Thesis: S.M., Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2014.55
Cataloged from PDF version of thesis.
Includes bibliographical references (pages 154-157).
Battery-ultracapacitors hybrid energy storage systems (ESS) could combine the high power density and high life cycle of ultracapacitors with the high energy density of batteries, which forms a promising energy storage system. In this thesis, an assessment of the benefits of the hybrid ESS relative to its battery-only counterpart in pulse-load applications is investigated for both Nickel-Metal Hydride (NiMH) batteries and Lithium-ion (Li-ion) batteries, and under different load profiles. Specifically, the hybrid ESS in this assessment is of the simplest type - paralleling the ultracapacitors across the batteries without any power electronics interface between them. To quantify this assessment, Discharge Capacity(0) is defined as the amount of energy one can draw out of an ESS per unit charge supplied by this ESS. The metric for quantifying the benefits is energy efficiency gain, defined as the percentage increase in the discharge capability of the hybrid ESS over its battery-only counterpart. The investigation proves that the hybrid system is more beneficial over the battery-only system in terms of how much energy it can output at a specific state-of-charge level. Among the test cases covered by this thesis, the increase in the output energy of Li-ion battery systems by incorporating ultracapacitors can reach to 17% and that of Ni-MH battery systems can reach to 33%. This thesis also shows that the benefits of paralleling ultracapactors across batteries depended upon the discharge profile of the load, the battery type and the capacitance. The benefits increase quadratically with the pulse amplitude, decreases linearly with the duty cycle and inverse with the pulse period. Moreover, capacitors with higher capacitance and lower ESR yield to larger benefits. And for batteries with a higher ESR, the ultracapacitors will show more benefits than for batteries with low ESR.
by Yiou He.
S.M.
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Kreinar, David J. "Energy Management Techniques for Hybrid Electric Unmanned Aircraft Systems." University of Dayton / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=dayton159640308960136.
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Lammers, Peter J. "Energy and nutrient cycling in pig production systems." [Ames, Iowa : Iowa State University], 2009.
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Coppez, Gabrielle. "Optimal sizing of hybrid renewable energy systems for rural electrification." Master's thesis, University of Cape Town, 2011. http://hdl.handle.net/11427/10274.
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Includes bibliograhical references.This project has the objective of creating a tool for feasibility assessment and recommendations of sizing of hybrid renewable energy systems in rural areas in South Africa. This involves the development of a tool which would analyse information input about the climate of the area and the load demand.
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kollappillai, Murugan Sai Varun. "Analysis of Hybrid Offshore Floating Wind and Marine Power." Thesis, Högskolan i Halmstad, Akademin för ekonomi, teknik och naturvetenskap, 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:hh:diva-36861.
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Wind energy is a major part of renewable energy production. With fossil fuel depletion and climate change at the cusp, it is an absolute need to implement or evolve the current source or utilization of renewable energy. The wind has been dominating the onshore for many decades and offshore wind turbines are available at shallow depths. To extract more wind energy source deep sea location is recommended. Also, in deep seas, ocean current energy is utilized very sparsely compared to the dominating wind and solar energy. So far no hybrid offshore horizontal axis and ocean current system are in existence. Based on the depth of the sea water the offshore floating structure is classified. Usually, for any floating structure stability is an apprehension. In an offshore floating structure, the damping with respect to the thrust force exerted on the wind turbine will affect the life of the wind turbine. During high wind speed, the angle of inclination would go up to about 4 degrees. The time required for the floating structure to come to rest may also be high. We present an analysis based on an existing floating structure which is a ballast stabilized the floating structure. In this paper, we add an additional submerged turbine and do a 2D analysis on the floating structure to find out whether the structure’s oscillation is well damped or not. We also discuss whether the weight of the submerged will influence the stability or by changing the radius of blades of the submerged turbine will affect the damping.
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Gan, Leong Kit. "Improving the performance of hybrid wind-diesel-battery systems." Thesis, University of Edinburgh, 2017. http://hdl.handle.net/1842/31482.
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Off-grid hybrid renewable energy systems are known as an attractive and sustainable solution for supplying clean electricity to autonomous consumers. Typically, this applies to the communities that are located in remote or islanded areas where it is not cost-effective to extend the grid facilities to these regions. In addition, the use of diesel generators for electricity supply in these remote locations are proven to be uneconomical due to the difficult terrain which translates into high fuel transportation costs. The use of renewable energy sources, coupling with the diesel generator allows for the diesel fuel to be offset. However, to date, a common design standard for the off-grid system has yet to be found and some challenges still exist while attempting to design a reliable system. These include the sizing of hybrid systems, coordination between the operation of dissimilar power generators and the fluctuating load demands, optimal utilisation of the renewable energy resources and identifying the underlying principles which reduce the reliability of the off-grid systems. In order to address these challenges, this research has first endeavoured into developing a sizing algorithm which particularly seeks the optimal size of the batteries and the diesel generator usage. The batteries and diesel generator function in filling the gap between the power generated from the renewable energy resources and the load demand. Thus, the load requirement is also an important factor in determining the cost-effectiveness of the overall system in the long run. A sensitivity analysis is carried out to provide a better understanding of the relationship between the assessed renewable energy resources, the load demand, the storage capacity and the diesel generator fuel usage. The thesis also presents the modelling, simulation and experimental work on the proposed hybrid wind-diesel-battery system. These are being implemented with a full-scale system and they are based on the off-the-shelf components. A novel algorithm to optimise the operation of a diesel generator is also proposed. The steady-state and dynamic analysis of the proposed system are presented, from both simulation and an experimental perspective. Three single-phase grid-forming inverters and a fixed speed wind turbine are used as a platform for case studies. The grid-forming inverters adopt droop control method which allows parallel operation of several grid-forming sources. Droop control-based inverters are known as independent and autonomous due to the elimination of intercommunication links among distributed converters. Moreover, the adopted fixed speed wind turbine employs a squirrel cage induction generator which is well known for its robustness, high reliability, simple operation and low maintenance. The results show a good correlation between the modelling, the experimental measurements, and the field tested results. The final stage of this research explores the effect of tower shadow on off-grid systems. Common tower designs for small wind turbine applications, which are the tubular and the lattice configurations, are considered in this work. They generate dissimilar tower shadow profiles due to the difference in structure. In this research, they are analytically modelled for a wind turbine which is being constructed as a downwind configuration. It is proven that tower shadow indeed brings negative consequence to the system, particularly its influence on battery lifetime within an off-grid system. This detrimental effect occurs when power generation closely matches the load demand. In this situation, small frequent charging and discharging cycles or the so called microcycles, take place. The battery lifetime reduction due to these microcycles has been quantified and it is proven that they are not negligible and should be taken into consideration while designing an off-grid hybrid system.
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De, Villiers Daniel Johannes. "Hybrid energy harvesting system for a condition monitoring mote." Thesis, Cape Peninsula University of Technology, 2009. http://hdl.handle.net/20.500.11838/1067.
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Thesis (MTech (Electrical Engineering))--Cape Peninsula University of Technology, 2009Traditional high voltage power transformers feature sensors measuring basic parameters from oil and gas and are limited to on-site monitoring. Unforeseen failures and breakdowns on these transformers have led to extensive financial losses even with planned maintenance schedules in place. A distinct need has arisen to actively monitor and identify causes of such failures. However, no or little infrastructure exists for effective remote condition monitoring. Wireless sensor networks can be introduced to actively monitor and identify causes of such failures. Sensor motes in the network are battery operated and therefore constrained by limited energy in these batteries. An alternative to battery-powered sensor motes is the conversion of available energy harvested from the surrounding environment into useable electrical energy powering the sensor motes. The primary objective of this research was to examine methods to harvest energy from both the environment and high voltage power transformer. A low cost and feasibly sized hybrid energy harvesting power management prototype was successfully developed that enabled sustained sensor mote operation for prolonged condition monitoring of high voltage transformers. The sensor mote utilised a piezoelectric cantilever to generate usable electrical energy from the transformer tank vibration. Together with solar energy harvesting, the system allowed for a battery-less self-sustained wireless sensor mote capable of autonomously monitoring its surroundings. The power management system's modular architecture provided for the inclusion of additional energy harvesting techniques. This allowed condition monitoring solutions not exclusively for power transformers but proposed an extensible condition monitoring solution for various applications.
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Wollaeger, James P. "ITS in Energy Management Systems of PHEV's." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1330704818.
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Mayilo, Sergiy. "Exploiting Energy Transfer in Hybrid Metal and Semiconductor Nanoparticle Systems for Biosensing and Energy Harvesting." Diss., lmu, 2009. http://nbn-resolving.de/urn:nbn:de:bvb:19-102229.
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Bazan, Peter [Verfasser], and Reinhard [Gutachter] German. "Hybrid Simulation of Smart Energy Systems / Peter Bazan ; Gutachter: Reinhard German." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2017. http://d-nb.info/1144619203/34.
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Zhang, Xiaodong, and 张晓东. "Design and implementation of auxiliary energy systems for hybrid electric vehicles." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2011. http://hub.hku.hk/bib/B46596641.
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Greenhut, Andrew David. "Modeling and analysis of hybrid geothermal-solar thermal energy conversion systems." Thesis, Massachusetts Institute of Technology, 2009. http://hdl.handle.net/1721.1/58087.
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Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, February 2010.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 116-118).
Innovative solar-geothermal hybrid energy conversion systems were developed for low enthalpy geothermal resources augmented with solar energy. The goal is to find cost-effective hybrid power cycles that take advantage of the potential synergies of solar thermal and geothermal resources. One aspect is to determine the hybrid configuration that yields the highest annualized electricity generation. The levelized cost of electricity (LCOE) is estimated using equipment costing rules of thumb developed from Aspen HTFS and Aspen ICARUS software and from other sources. Detailed models for the hybrid solar-geothermal system were developed using Aspen Plus and Aspen Dynamics. Turbine flexibility relative to vapor flow rate, temperature and pressure variations was analyzed. In one scenario, a parametric steady-state study was carried out to examine the performance over the range of conditions resulting from diurnal and seasonal variations. The results of the diurnal and seasonal parametric studies were grossly weighted to approximate a typical year in Nevada, and these results led to an estimate of the annualized electricity generation. In another scenario, a dynamic model was selected from possible "greenfield" hybrid systems and used to examine the transient performance for a typical January day and a typical July day in Nevada. The dynamic model approximates the thermal inertial of the heat exchangers and the working fluids in the exchangers, solar collectors, piping and storage tanks. The dynamic model is driven with forcing functions for solar input and ambient temperature to approximate the typical winter and summer days.
(cont.) In all cases, solar energy was found to come at a higher cost per kW capacity than geothermal when the cost of geothermal wells was not considered. However, including well costs had an effect of evening out the levelized cost of electricity. Model complexity increased as more solar heat was added to existing geothermal systems, which suggests that moving a higher exergy heat source down to a lower exergy heat source is difficult, especially given the transient nature of the solar resource. The models developed in this thesis demonstrate the design decisions and complex dynamic behavior inherent in this type of hybrid system.
by Andrew David Greenhut.
S.M.
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Samuel, Durair Raj Kingsly Jebakumar. "Modeling, Control and Prototyping of Alternative Energy Storage Systems for Hybrid Vehicles." The Ohio State University, 2012. http://rave.ohiolink.edu/etdc/view?acc_num=osu1331140529.
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Swanepoel, Paul. "A forecasting model for photovoltaic module energy production." Thesis, Nelson Mandela Metropolitan University, 2011. http://hdl.handle.net/10948/1420.
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Energy is of concern for governments and economies all over the world. As conventional methods of energy production are facing the prospect of depleting fossil fuel reserves, economies are facing energy risks. With this tension, various threats arise in terms of energy supply security. A shift from intensive fossil fuel consumption to alternative energy consumption combined with the calculated use of fossil fuels needs to be implemented. Using the energy radiated from the sun and converted to electricity through photovoltaic energy conversion is one of the alternative and renewable sources to address the limited fossil fuel dilemma. South Africa receives an abundance of sunlight irradiance, but limited knowledge of the implementation and possible energy yield of photovoltaic energy production in South Africa is available. Photovoltaic energy yield knowledge is vital in applications for farms, rural areas and remote transmitting devices where the construction of electricity grids are not cost effective. In this study various meteorological and energy parameters about photovoltaics were captured in Port Elizabeth (South Africa) and analyzed, with data being recorded every few seconds. A model for mean daily photovoltaic power output was developed and the relationships between the independent variables analyzed. A model was developed that can forecast mean daily photovoltaic power output using only temperature derived variables and time. The mean daily photovoltaic power model can then easily be used to forecast daily photovoltaic energy output using the number of sunlight seconds in a given day.
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Hines, Paul. "WindSim Study of Hybrid Wind Farm in Complex Terrain." Thesis, Högskolan på Gotland, Institutionen för kultur, energi och miljö, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-216994.
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A annual nergy production analysis was undertaken to compare wind resources and annual energy production as estimated by WAsP and Windsim. Nordex Sverige AB has designed a wind farm with the help of WAsP and this study will involve the examination of this site with Windsim. Two site formations are of interest, one with the same class of turbine and one with a mix of two turbine types. The study is interested in the effect on annual energy production as estimated by the different software of employing a hybrid layout using wind turbines of different height.The results showed that whilst initial estimations of total energy production without wake losses appear very similar between WAsP and Windsim the ways in which the software are treating individual turbines within the planned farm can be quite different because of different physics. The analysis of the „hybrid‟ turbine layout showed significant increases in estimated annual energy production when a turbine with a higher tower and larger rotor diameter was used in a hybrid arrangement. Estimated annual energy losses on the turbines that were not changed in favour of a larger turbine were small. However, no great benefit in estimated turbine efficiency was achieved through the mixing of turbine types with different hub heights. The gains in annual energy production estimated by both software are however significant with increased production of 18 % across the entire farm when comparing the „hybrid‟ layout to a farm based on only the smaller of the two turbine types.
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Shaheen, Murtadha A. "POWER MAXIMIZATION FOR PYROELECTRIC, PIEZOELECTRIC, AND HYBRID ENERGY HARVESTING." VCU Scholars Compass, 2016. http://scholarscompass.vcu.edu/etd/4462.
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The goal of this dissertation consists of improving the efficiency of energy harvesting using pyroelectric and piezoelectric materials in a system by the proper characterization of electrical parameters, widening frequency, and coupling of both effects with the appropriate parameters.
A new simple stand-alone method of characterizing the impedance of a pyroelectric cell has been demonstrated. This method utilizes a Pyroelectric single pole low pass filter technique, PSLPF. Utilizing the properties of a PSLPF, where a known input voltage is applied and capacitance Cp and resistance Rp can be calculated at a frequency of 1 mHz to 1 Hz. This method demonstrates that for pyroelectric materials the impedance depends on two major factors: average working temperature, and the heating rate.
Design and implementation of a hybrid approach using multiple piezoelectric cantilevers is presented. This is done to achieve mechanical and electrical tuning, along with bandwidth widening. In addition, a hybrid tuning technique with an improved adjusting capacitor method was applied. An toroid inductor of 700 mH is shunted in to the load resistance and shunt capacitance. Results show an extended frequency range up to 12 resonance frequencies (300% improvement) with improved power up to 197%.
Finally, a hybrid piezoelectric and pyroelectric system is designed and tested. Using a voltage doubler, circuit for rectifying and collecting pyroelectric and piezoelectric voltages individually is proposed. The investigation showed that the hybrid energy is possible using the voltage doubler circuit from two independent sources for pyroelectrictity and piezoelectricity due to marked differences of optimal performance.
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Allan, James. "The development and characterisation of enhanced hybrid solar photovoltaic thermal systems." Thesis, Brunel University, 2015. http://bura.brunel.ac.uk/handle/2438/11624.
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A photovoltaic thermal solar collector (PVT) produces both heat and electricity from a single panel. PVT collectors produce more energy, for a given area, than conventional electricity and heat producing panels, which means they are a promising technology for applications with limited space, such as building integration. This work has been broken down into 3 subprojects focusing on the development of PVT technology. In the first subproject an experimental testing facility was constructed to characterise the performance of PVT collectors. The collectors under investigation were assembled by combining bespoke thermal absorbers and PV laminates. Of the two designs tested, the serpentine design had the highest combined efficiency of 61% with an 8% electrical fraction. The header riser design had a combined efficiency of 59% with an electrical fraction of 8%. This was in agreement with other results published in literature and highlights the potential for manufacturers of bespoke thermal absorbers and PV devices to combine their products into a single PVT device that could achieve improved efficiency over a given roof area. In the second project a numerical approach using computational fluid dynamics was developed to simulate the performance of a solar thermal collector. Thermal efficiency curves were simulated and the heat removal factor and heat loss coefficient differed from the experimental measurements by a maximum of 12.1% and 2.9% respectively. The discrepancies in the findings is attributed to uncertainty in the degree of thermal contact between the absorber and the piping. Despite not perfectly matching the experimental results, the CFD approach also served as a useful tool to carry out performance comparisons of different collector designs and flow conditions. The effect of 5 different flow configurations for a header collector was investigated. It was found that the most efficient design had uniform flow through the pipe work which was in agreement with other studies. The temperature induced voltage mismatch, that occurs in the PV cells of PVT collector was also investigated. It was concluded that the temperature variation was not limiting and the way in which PV cells are wired together on the surface of a PVT collector did not influence the combined electrical power output.
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Pardo, García Nicolás. "Energy efficiency improvement of hybrid ground coupled HVAC systems from thermal energy generation and storage management." Doctoral thesis, Universitat Politècnica de València, 2009. http://hdl.handle.net/10251/6065.
Повний текст джерелаАнотація:
Nowadays, the increasing of the energy consumption is producing serious
changes in the natural environment as the global warming. Around the 40%
of all greenhouse gas emissions in developed countries come from the building
equipments, where approximately 60% are produced by the air conditioning
systems. In this context, ground coupled heat pumps are an attractive solution
as air conditioning systems in commercial buildings due to their higher
efficiency compared with the conventional air to water heat pump. In fact,
the American Environmental Protection Agency recognizes ground coupled
heat pump systems among the most efficient and comfortable systems available
today. Nevertheless, the energy efficiency of the ground coupled heat
pumps could be improve by means a properly management of the di erent
equipments which form them.
The objective of the research of this PhD thesis will be the development
of management strategies in the air conditioning system based on the ground
coupled heat pumps to improve its energy efficiency at the same time that we
keep the thermal comfort in the conditioned areas. The energy management
strategies will be oriented in the three ways: combining of several generation
systems (ground coupled heat pump and air to water heat pump), decoupling
thermal generation from thermal distribution (by means a thermal storage
device) and strategies based on the management of the devices of the system
(by means of continuous regulation of them).
From the results of this research we can obtain two main conclusions.
The rst one is that a properly management of a system composed by a
thermal storage, an air to water heat pump and a ground coupled heat pump
produce an improvement of the energy efficiency around a 40% respect to a
conventional system and around a 18% respect to a geothermal system. The
second main conclusion of this thesis is that a properly management strategy
in continuous regulation of the devices which are part of a ground coupled ..Pardo García, N. (2009). Energy efficiency improvement of hybrid ground coupled HVAC systems from thermal energy generation and storage management [Tesis doctoral no publicada]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/6065
Palancia
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Clark, Craig. "Use of hybrid ventilation techniques for improved energy efficiency of fan systems." Thesis, Georgia Institute of Technology, 2010. http://hdl.handle.net/1853/33962.
Повний текст джерелаАнотація:
The goal of this thesis was to improve the energy efficiency of building ventilation systems by exploring new methods of applying natural ventilation concepts. Strictly natural systems have limitations in which climates they can function or can provide optimal performance; these limitations lead to the use of mechanical or hybrid ventilation. This study looked at methods of combining the operation of the systems, such that the natural components improve the efficiency of the mechanical system.
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Curtis, Daniel Joseph. "Nuclear renewable oil shale hybrid energy systems : configuration, performance, and development pathways." Thesis, Massachusetts Institute of Technology, 2015. http://hdl.handle.net/1721.1/97964.
Повний текст джерелаАнотація:
Thesis: S.M., Massachusetts Institute of Technology, Department of Nuclear Science and Engineering, 2015.Cataloged from PDF version of thesis.
Includes bibliographical references.
Nuclear Renewable Oil Shale Systems (NROSS) are a class of large Hybrid Energy Systems in which nuclear reactors provide the primary energy used to produce shale oil from kerogen deposits and also provide flexible, dispatchable electricity to the grid. Kerogen is solid organic matter trapped in sedimentary shale, and the formations of kerogen oil shale in the western United States are the largest and densest hydrocarbon resource on the planet. When heated above 300 °C, kerogen decomposes into oil, gas, and char. NROSS couples electricity and transportation fuel production in a single operation, reduces lifecycle carbon emissions from the fuel produced, improves economics for the nuclear plant, and enables a major shift toward a very-low-carbon electricity grid. The nuclear reactor driving an NROSS system would operate steadily at full power, providing steam for shale heating in closed steam lines when the price of electricity is low and electricity to the grid when the price of electricity is high. Because oil shale has low thermal conductivity, heat input to the shale can be cycled as needed without disrupting the steady increase in average temperature. The target average shale temperature of 350 °C would be reached over 2 years using two heating stages in the baseline configuration driven by light water reactors. First stage heating brings the shale to an intermediate temperature, assumed to be 210 °C in this study. The second heating stage isolates the steam delivery line from the reactor and uses electricity, purchased when prices are low, to increase steam temperature and bring the shale to 350 °C. This capacity to absorb low price electricity mitigates the tendency for electricity prices to collapse to zero, or potentially negative values, during periods of peak wind and solar output. The analysis herein shows that liquid fuels produced by a baseline NROSS would have the lowest life cycle greenhouse gas impact of any presently available fossil liquid fuels and that operation as part of an NROSS complex would increase reactor revenues by 41% over a stand-alone baseload reactor. The flexible, dispatchable electricity provided by NROSS could also enable the transition to a very-low-carbon grid in which renewables are widely deployed and the NROSS provides variable output to balance their uncontrolled output to meet demand. Fully deployed, NROSS could require tens or hundreds of reactors. Large fleet operations and local mass production of the necessary hardware could bring about substantial reductions in system cost as development proceeds, potentially offering a pathway to jump start and maximize the realization of the mass production cost savings envisioned for small modular reactors. The development pathway to achieve large scale NROSS deployment will be complicated, however, requiring involvement from many government agencies, a demonstration system, and a complex commercialization effort with partnered nuclear vendors, utilities, and petroleum system developers.
by Daniel Joseph Curtis.
S.M.
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Esmaili, Gholamreza. "Application of advanced power electronics in renewable energy sourcesand hybrid generating systems." The Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc_num=osu1141850833.
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Vergara, Idalides Jose. "A Hybrid Privacy-Preserving Mechanism for Participatory Sensing Systems." Scholar Commons, 2014. https://scholarcommons.usf.edu/etd/5394.
Повний текст джерелаАнотація:
Participatory Sensing (PS) is a new data collection paradigm in which people use their cellular phone resources to sense and transmit data of interest to address a collective problem that would have been very difficult to assess otherwise. Although many PS-based applications can be foreseen to solve interesting and useful problems, many of them have not been fully implemented due to privacy concerns. As a result, several privacy-preserving mechanisms have been proposed. This dissertation presents the state-of-the-art of privacy-preserving mechanisms for PS systems. It includes a new taxonomy and describes the most important issues in the design, implementation, and evaluation of privacy-preserving mechanisms. Then, the most important mechanisms available in the literature are described, classified and qualitatively evaluated based on design issues. The dissertation also presents a model to study the interactions between privacy-preserving, incentive and inference mechanisms and the effects that they may have on one another, and more importantly, on the quality of information that the system provides to the final user.
Then, a new hybrid privacy-preserving mechanism is proposed. This algorithm dynamically divides the area of interest into cells of different sizes according to the variability of the variable of interest being measured and chooses between two privacy-preserving mechanisms depending on the size of the cell. In small cells, where participants can be identified easier, the algorithm uses a double-encryption technique to protect the privacy of the participants and increase the quality of the information. In bigger cells, where the variability of the variable of interest is low, data anonymization and obfuscation techniques are used to protect the actual location (privacy) of the participant. The proposed mechanism is evaluated along with other privacy-preserving mechanisms using a real PS system for air pollution monitoring. The systems are evaluated considering the quality of information provided to the final user, energy consumption, and the level of privacy protection. This last criterion is evaluated when the adversary is able to compromise one or several records in the system. The experiments show the superior performance of proposed mechanism and the existing trade-offs in terms of privacy, quality of information, and energy consumption.
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Vieira, Giovani Giulio Tristão Thibes. "Hybrid powertrains analysis for ship propulsion using energy storage." Universidade de São Paulo, 2018. http://www.teses.usp.br/teses/disponiveis/3/3143/tde-17122018-090614/.
Повний текст джерелаАнотація:
The ship emission already occupy the eighth position in the world biggest emitters ranking. This happens because the ship operations have a huge demand variation therefore in order to reduce the ship emissions is required an efficient operation of the generators. This work aims at integrating advanced storage systems into the operation of diesel generators. The variation of the operation point has a direct interference on the emissions and on the diesel consumption, this variation is allowed through the frequency and voltage control. The use of lithium batteries for various operation points of the generators is analyzed. The use of an energy storage system allowed the operation of the generators in a better operation point therefore there was a reduction in diesel consumption and in CO2 emissions when the diesel generators. The main result of this work could also shed light in the operation of isolated power systems equipped with advanced storage systems and diesel generators.As emissões dos navios já ocupam a oitava posição entre os países com maior emissão no mundo. Isso pode ser explicado pelo fato de que as operações dos navios têm uma grande variação de demanda de potência, com isso a operação inteligente dos geradores a diesel é fundamental para a redução das emissões. A abordagem desenvolvida nesse trabalho integra o uso de sistemas de armazenamento avançados na operação dos geradores a diesel. A variação do ponto de operação dos geradores a diesel interfere diretamente no consumo e nas emissões, essa variação só é possível por meio do controle de frequência e tensão providos pelo sistema de armazenamento de energia. Nesse trabalho foram analisados o uso de baterias de lítio para diferentes pontos de operação do gerador a diesel. O uso das baterias possibilitou a operação dos geradores num melhor ponto de carga com isso houve uma redução das emissões e do consumo de combustível. Os resultados encontrados nesse trabalho podem ser extrapolados qualitativamente para outros sistemas de potência offshore, como plataformas de petróleo e de perfuração, que operem com sistemas de baterias avançadas e geradores a diesel.
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Luo, Dexin. "Design of highly distributed biofuel production systems." Diss., Georgia Institute of Technology, 2011. http://hdl.handle.net/1853/45878.
Повний текст джерелаАнотація:
This thesis develops quantitative methods for evaluation and design of large-scale biofuel production systems with a particular focus on bioreactor-based fuel systems. In Chapter 2, a lifecycle assessment (LCA) method is integrated with chemical process modeling to select from different process designs the one that maximizes the energy efficiency and minimizes the environmental impact of a production system. An algae-based ethanol production technology, which is in the process of commercialization, is used as a case study. Motivated by this case study, Chapter 3 studies the selection of process designs and production capacity of highly distributed bioreactor-based fuel system from an economic perspective. Nonlinear optimization models based on net present value maximization are developed that aim at selecting the optimal capacities of production equipment for both integrated and distributed-centralized process designs on symmetric production layouts. Global sensitivity analysis based on Monte Carlo estimates is performed to show the impact of different parameters on the optimal capacity decision and the corresponding net present value. Conditional Value at Risk optimization is used to compare the optimal capacity for a risk-neutral planner versus a risk-averse decision maker. Chapter 4 studies mobile distributed processing in biofuel industry as vehicle routing problem and production equipment location with an underlying pipeline network as facility location problem with a focus on general production costs. Formulations and algorithms are developed to explore how fixed cost and concavity in the production cost increases the theoretical complexity of these problems.
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Celesin, Michael Enoch. "Application and Characterization of Self-Assembled Monolayers In Hybrid Electronic Systems." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4875.
Повний текст джерелаАнотація:
In this study, we explore ultra-thin insulators of organic and inorganic composition and their potential role as high-speed rectifiers. Typical applications for these structures include IR sensing, chemical detection, high speed logic circuits, and MEMS enhancements. While there are many elements in the functional group required to create a rectifying antenna (rectenna), the primary thrust of this work is on the rectifier element itself.
To achieve these research goals, a very good understanding of quantum tunneling was required to model the underlying phenomenon of charge conduction. The development of a multi-variable optimization routine for tunneling prediction was required. MATLAB was selected as the programming language for this application because of its flexibility and relative ease of use for simulation purposes. Modeling of physical processes, control of electromechanical systems, and simulation of ion implantation were also to be undertaken.
To advance the process science, a lithographic mask set was made which utilized the information gleaned from the theoretical simulations and initial basic experiments to create a number of diode test structures. This came to include the creation of generations of mask sets--each optimizing various parameters including testability, alignment, contact area, device density, and process ease. Following this work, a complete toolset for the creation of "soft" contact top metals was required and needed to be developed. Ultra-flat substrates were needed to improve device reliability and measurement consistency.
The final phase of research included measurement and characterization of the resultant structures. Basic DC electrical characterization of the organic monolayers would be accomplished using metal probes. Statistical studies of reliability and process yield could then easily be carried out. The rectification ratio (ratio of forward over reverse current at a given voltage magnitude) was found to be a reliable indicator of diode performance in the low frequency ranges. This would mean writing additional code in MATLAB to assist in the automatic analysis for the acquired IV curves. Progression to AC / RF measurements of tunneling performance was to be accomplished using relatively low frequencies (below 100 MHz). Finally, the organic films themselves would be studied for consistency, impedance characteristics, incidence of defects, and thickness by a variety of metrology techniques.
This project resulted in a number of advances to the state-of-the-art in nanofabrication using organic monolayers. A very detailed review of the state of alkanethiol research was presented and submitted for publication. A single pot technique was developed to softly deposit metal nanoparticles onto a charged surface with a high degree of control. A temporary contact method using pure, sub-cooled gallium liquid metal was used to probe organic monolayers and plot IV curves with better understanding of surface states than before. An inkjet printer solution was devised for top contact printing which involved the development and production of a work-up free insulator ink which is water soluble and printable to resolutions of about 25 um. Localized selective chemical crosslinking was found to reduce printed ink solubility following deposition. Future work will likely include additional exploration of crosslinkable Langmuir-Blodgett films as MIM insulators. Stability and testing will hinge on the fabrication of enclosures or packages for environmental isolation.
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Walter, Oliver [Verfasser], Stefan [Akademischer Betreuer] Becker, Stefan [Gutachter] Becker, and Jürgen [Gutachter] Karl. "Hybrid Energy Storage in Future Energy Systems / Oliver Walter ; Gutachter: Stefan Becker, Jürgen Karl ; Betreuer: Stefan Becker." Erlangen : Friedrich-Alexander-Universität Erlangen-Nürnberg (FAU), 2021. http://d-nb.info/1238899056/34.
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Deal, Michael William. "Net Primary Production in Three Bioenergy Crop Systems Following Land Conversion." University of Toledo / OhioLINK, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1309362383.
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Miles, Alexander Ashton. "Hybrid Optical Systems: From Nanometer to Multi-Meter Scales." Diss., The University of Arizona, 2015. http://hdl.handle.net/10150/596135.
Повний текст джерелаАнотація:
Hybridizing, in general, is the approach of combining multiple technologies, materials, or designs such to mitigate the drawbacks and enhance the benefits. The result of this combination can be referred to as a hybrid. The projects described in this work concern a number of these hybrids. The collection of projects are limited to optical applications, but are otherwise enormously different. There is perhaps no better way to illustrate this breadth than their characteristic length-scale. That is, the general size of the elements being hybridized. Ten orders of magnitude lie between the smallest system described and largest systems. At the several-nanometer scale, a single component of a composite optical material. Diamond possesses a unique combination of refractive and dispersive optical properties, making it an attractive optical material. Unfortunately, the lowest cost diamond available possesses large amounts of impurities and color. In an attempt to remove the visible color from commercially available detonation-origin nanodiamond powders we developed a facile three-step cleaning process. This process and the resulting qualities of the nanodiamond are discussed. At tens to hundreds of nanometers scale, we have worked to optimize a complete composite material system; a combination of Polystyrene-b-poly (2-vinyl pyridine) (PS-b-P2VP), a block co-polymer with self-assembly properties, and controlled size iron platinum (FePt) nanoparticles. The applications in mind are magnetic field sensors, used in medical testing and physical experiments, and fiber optic isolators, used extensively in telecommunications networks. These composites exhibited commercially significant Verdet constants in room temperature Faraday rotation measurements, and possess processing benefits over the current state-of-the-art magneto-optically active materials. Several behaviors with respect to wavelength, particle loading, and primary particle size are discussed. At the micron to centimeter scale, we have designed and characterized a high-speed fiber-optic switch for telecommunications networks capable of reconfiguring 100 times faster than currently available technologies with comparable port counts. The switch is an unconventional hybrid of the micron-scale optics of single-mode fiber modes, and the centimeter scale of free-space holography. Built primarily using off-the-shelf components and a commercially available digital micro-mirror device (DMD), the switch is protocol and bit-rate agnostic, robust against random mirror failure, and provides the basic building block for a fully reconfigurable optical add drop multiplexer (ROADM).Finally, at the scale of several meters, we address a system that hybridizes two established methods for harvesting solar energy. Sunlight can be captured as electricity using photovoltaics (PV), as well as heat, often called concentrated solar power (CSP). Each approach has benefits and drawbacks which will be discussed. A system possessing the peak efficiency of PV, with the deployable storage of CSP, would most effectively meet demand around the clock. In order to combine these technologies, we have developed an approach for designing a dichroic coating to optimize performance of such a system utilizing multi-junction photovoltaic cells while diverting unused light to heat collection. Through careful design substantial improvement to system efficiencies are shown to be possible.
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Uhlar, Stefan. "Energy consistent time-integration of hybrid multibody systems. Energie-konsistente Zeitintegration hybrider Mehrkörpersysteme." Siegen OAI Universitätsbibliothek Siegen, 2009. http://d-nb.info/999230433/34.
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Esmaili, Gholamreza. "Application of advanced power electronics in renewable energy sources and hybrid generating systems." Columbus, Ohio : Ohio State University, 2006. http://rave.ohiolink.edu/etdc/view?acc%5Fnum=osu1141850833.
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Karakus, Uzuner Melike [Verfasser]. "Charge carrier dynamics in hybrid systems for solar energy conversion / Melike Karakus Uzuner." Mainz : Universitätsbibliothek Mainz, 2017. http://d-nb.info/1132608430/34.
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Sharafi, Masoud. "Multi-objective optimal design of hybrid renewable energy systems using simulation-based optimization." Elsevier, 2014. http://hdl.handle.net/1993/31040.
Повний текст джерелаАнотація:
Renewable energy (RE) resources are relatively unpredictable and dependent on climatic conditions. The negative effects of existing randomness in RE resources can be reduced by the integration of RE resources into what is called Hybrid Renewable Energy Systems (HRES). The design of HRES remains as a complicated problem since there is uncertainty in energy prices, demand, and RE sources. In addition, it is a multi-objective design since several conflicting objectives must be considered. In this thesis, an optimal sizing approach has been proposed to aid decision makers in sizing and performance analysis of this kind of energy supply systems.
First, a straightforward methodology based on ε-constraint method is proposed for optimal sizing of HRESs containing RE power generators and two storage devices. The ε-constraint method has been applied to minimize simultaneously the total net present cost of the system, unmet load, and fuel emission. A simulation-based particle swarm optimization approach has been used to tackle the multi-objective optimization problem.
In the next step, a Pareto-based search technique, named dynamic multi-objective particle swarm optimization, has been performed to improve the quality of the Pareto front (PF) approximated by the ε-constraint method. The proposed method is examined for a case study including wind turbines, photovoltaic panels, diesel generators, batteries, fuel cells, electrolyzers, and hydrogen tanks. Well-known metrics from the literature are used to evaluate the generated PF.
Afterward, a multi-objective approach is presented to consider the economic, reliability and environmental issues at various renewable energy ratio values when optimizing the design of building energy supply systems. An existing commercial apartment building operating in a cold Canadian climate has been described to apply the proposed model. In this test application, the model investigates the potential use of RE resources for the building. Furthermore, the
application of plug-in electric vehicles instead of gasoline car for transportation is studied. Comparing model results against two well-known reported multi-objective algorithms has also been examined.
Finally, the existing uncertainties in RE and load are explicitly incorporated into the model to give more accurate and realistic results. An innovative and easy to implement stochastic multi-objective approach is introduced for optimal sizing of an HRES.February 2016
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Broday, Gabriel Renan. "Bidirectional DC-DC converters for hybrid energy storage systems in electric vehicle applications." Universidade Tecnológica Federal do Paraná, 2016. http://repositorio.utfpr.edu.br/jspui/handle/1/2411.
Повний текст джерелаАнотація:
Em um momento em que questões ambientais e a segurança energética estão numa posição de destaque, Veículos Elétricos (VEs) estão no centro das atenções. Entretanto, ainda é difícil para eles substituir os tradicionais veículos de combustão interna e a razão principal para isso é o seu sistema de energia. Normalmente, devido a suas características, baterias são usadas como banco de energia para VEs. No entanto, baterias também apresentam algumas limitações para essa aplicação e o problema no sistema de energia é relacionado a essas limitações. Uma das soluções propostas é se colocar baterias e supercapacitores (SC) em paralelo, resultando em um Sistema Híbrido de Armazenamento de Energia (SHAE). Para fazer essa configuração possível e o fluxo de potência controlável em um SHAE, um conversor CC-CC bidirecional interfaceando a bateria e o SC é necessário. Levando isso em consideração, o estudo de topologias CC-CC bidirecionais é apresentado nessa Dissertação de Mestrado. Primeiro, o estudo de um conversor CC-CC bidirecional com indutor dividido, envolvendo sua análise teórica em regime permanente, análise dinâmica e uma metodologia de projeto com resultados de simulação, é apresentado, resultando na construção de um protótipo experimental com as seguintes especificações de projeto: Fonte de tensão 1 de 300 V, fonte de tensão 2 de 96 V, frequência de comutação de 20 kHz e potência nominal de 1000 W. Então, o estudo de uma segunda topologia, um conversor CC-CC Buck-Boost ZVS bidirecional, envolvendo sua análise em regime permanente e uma metodologia de projeto com resultados de simulação, também é apresentado.In an era where environmental issues and the energetic safety are in an outstanding position, Electric Vehicles (EVs) are in the spotlight. However, it is difficult for them to replace the ICE vehicles and the main reason for that it is their energy system. Normally, due to some of their characteristics, batteries are used as energy bank in Electric Vehicles. Nevertheless, batteries also present some limitations for this application and the energy system problem is related to these limitations. One of the proposed solutions is to place batteries and Supercapacitors (SC) in parallel, resulting in a Hybrid Energy Storage System (HESS). To make this configuration possible and the power flow controllable in the HESS, a bidirectional DC-DC converter interfacing the battery and the SC is necessary. Taking this into account, the study of bidirectional DC-DC topologies is presented in this Master’s Thesis. First, a study of a bidirectional DC-DC converter with tapped inductor, involving its theoretical steady state analysis, dynamic analysis and design methodology with simulation results, is presented, resulting in the design of an experimental prototype with the following design specifications: Voltage source 1 of 300 V, voltage source 2 of 96 V, switching frequency of 20 kHz and rated power of 1000 W. Then, the study of a second topology, a bidirectional ZVS Buck-Boost DC-DC converter, involving he steady state analysis and a design methodology with simulation results, is also presented.
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Amusat, O. O. "Design and optimization of hybrid renewable energy systems for off-grid continuous operations." Thesis, University College London (University of London), 2017. http://discovery.ucl.ac.uk/1566604/.
Повний текст джерелаАнотація:
The mining industry accounts for a significant portion of the energy demand by the industrial sector. The rising demand for metals around the world, coupled with the depletion of readily accessible ore deposits, has led to mining operations moving to more remote locations with no grid supply of energy. As a result, the operations require transport of fuel over large distances, leading to a significant increase in the overall mining cost. Renewable energy is considered to be the most promising solution to the mining industry energy problem. This work investigates the possibility of operating remote mines on local generation from renewables. A survey of recent literature revealed that while a lot of research had been done on hybrid renewable energy systems design and sizing, little thought had been given to accounting for the stochastic nature of renewable resources in the sizing process. Previous works focused on the sizing of PV-wind-battery systems; other potential generation and storage technologies were largely ignored. The challenge of intermittency in the power output of renewable generation systems had also largely been ignored. This thesis extends the state of the art on hybrid systems sizing by developing models and methodologies to address these challenges. A novel hybrid energy system integrating thermal and electrical renewable generation options with multiple large scale energy storage options is considered in this thesis. Models are developed for the different components of the energy system, with dynamic models incorporated for the material and energy balances of the storage alternatives, leading to a system of nonlinear differential algebraic equations (DAEs). The temporal nature of the renewable resources is accounted for by considering multiple stochastic renewable input scenarios generated from probability distribution functions (PDFs) as inputs into the system model. A reliability measure to quantify the impact of weather-based variability, called the modified loss of power supply probability, is developed. A bi-criteria sizing methodology which allows for the stochastic nature of renewable resources to be accounted for is presented. The approach combines the time series approach to reliability evaluation with a stochastic simulation model. Two approaches for mitigating the impact of intermittency in power outputs of renewable generation technologies are also developed. The first approach is based on system redesign, while the second approach is based on the introduction of an instantaneous response storage option. Case studies were presented to demonstrate the various methodologies. The results show that climate-based variability can have a significant impact on the cost and performance of hybrid energy systems and should always be accounted for in the sizing process. Intermittency needs to be accounted for in some form at the design stage as it can have an impact on the choice of technologies. The integration of thermal and electrical power generation and storage options provide a way to reduce hybrid system costs. The methodologies developed in this thesis are applicable to any location and can easily be extended to incorporate other generation and storage alternatives. They provide the decision maker with necessary information for making preliminary sizing decisions.