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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

ICT System Architecture for Smart Energy Container

Wu, Yiming January 2011 (has links)
Hybrid Energy Resource System (HERS) is studied and applied aroundworld in recent years. Control and monitor of them are quite important in realapplication. HERS also has the equirement to integral with power grid such asdistribution grid networks. Therefore, to design and implement the informationcommunication system following IEC 61850, which is most promising standard fordesign of substation communication and automation system, is necessary. This paperpresents the design of Information Communication Technology (ICT) architectureand Unified Modeling Language (UML) models and final implementation through LabVIEW programming for Smart Energy Container. Applying design following IEC61850 series standards allow the HERS can communicate and interoperate with other IEC61850 devices and SCADA systems. The implementation is applied to SmartEnergy Container which contains wind power, solar power, battery energy storagesystem, and hydrogen energy storage system. Verification and testing results shows thedesign is qualified to control and monitor Smart Energy Container. / Smart Energy Container
62

Feasibility study of an EV management system to provide Vehicle-to-Building considering battery degradation

Goncalves, Sofia January 2018 (has links)
The recent increase of electric cars adoption will inuence the electricity demand in the distributionnetworks which risks to be higher than the maximum power available in the grid, if not well planned. Forthis reason, it is on the DSOs and TSOs's interest to plan carefully coordinated charging of a bulk of EVsas well as assess the possibility of EVs acting as energy storages with the Vehicle-to-Grid (V2G) or Vehicleto-Building (V2B) capability. When parked and plugged into the electric grid, EVs will absorb energy andstore it, being also able to deliver electricity back to the grid/building (V2G/B system).This can be anoptimized process, performed by an aggregator, gathering multiple EVs that discharge the battery into thegrid at peak time and charge when there is low demand i.e. overnight and o-peak hours.Numerous studies have investigated the possibility of aggregating multiple EVs and optimizing theircharging and discharging schedules for peak load reduction or energy arbitrage with participation in theelectricity market. However, no study was found for optimizing a shared eet of EVs with daily reservationsfor dierent users trying to perform V2B. In this study an optimization modelling algorithm (mixed integerlinear problem - MILP) that manages the possible reservations of the shared eet of EVs, coordinates thecharging and discharging schedules, and provides V2B (Vehicle-to-Building), with the objective of minimizingenergy costs and accounting with battery ageing has been developed. A case study with real data for abuilding is carried out modelling dierent number of EVs for two dierent days in year 2017, one in Marchand other in June.Results show that the prots are higher for all cases when introducing V2B as compared to a no optimizationscenario: V2B with battery degradation (50 ore/kWh) has decreased daily variable electricity costsbetween 54 and 59% in March and 60 and 63% for June when compared without smart charging. Integrationof battery degradation cost in V2B applications is necessary and inuences signicantly the chargingand discharging strategies adopted by EV and nally the total daily costs: The total daily cost increaseby maximal 10% for the day in March and 13% for the day in June when comparing the scenario that hasstationary battery and uses only-charging model for EVs with the scenario applying V2B mode consideringa degradation cost of 80 ore/kWh. / Ö kningen av antalet elbilar kommer att påverka lasten i elnätet som riskerar att bli högre än kapacitetom det inte är väl planerat. Därför är det i elnätsföretags intresse att samordna laddningen av de flesta elbilarna samt att utvärdera möjligheterna att använda elbilar som energilager gentemot elnätet (Vehicleto-Grid,V2G) eller byggnader (Vehicle-to-Building, V2B). Vid parkering och anslutning till elnätet kommer elbilar att ladda energi och lagra den, samtidigt de kan leverera el tillbaka till elnätet eller byggnaden (V2G/V2B). Detta kan vara en optimerad process som utförs av en aggregator genom att ladda flera elbilar i låglasttimmar och ladda ur dem under höglasttimmar.Många studier har undersökt möjligheten att aggregera flera elbilar och optimera laddningsoch urladdningsplaner för topplastreduktion eller energiarbitrage på elmarknaden. Ingen studie har dock hittats för att optimera en gemensam flotta av elbilar med dagliga reservationer för olika användare som försöker utföra V2B. Denna studie har utvecklat en optimeringsmodell (blandad heltalsprogrammering MILP) som hanterar möjliga reservationer av en flotta av elbilar, koordinerar laddning och urladdning planering, och utför V2B för att minimera energikostnader med hänsyn till batteriets åldrande. En fallstudie för en byggnad genomfördes modellering av olika antal elbilar för två dagar 2017, en i mars och andra i juni.Resultaten visar att vinsten är högre i samtliga fall då man introducerar V2B jämfört med scenario utan optimering: V2B med batteriladdningskostnad 50 öre/kWh minskade dagliga rörliga elkostnader mellan 54% och 59% i mars och mellan 60% och 63% i juni jämfört med utan smart laddning. Att inkludera batteriladdningskostnaden i V2B-applikationer är nödvändigt och har en signifikant inverkan på laddningsstrategierna och de totala kostnaderna: De totala dagliga kostnaderna ökar med upp till 10% i mars och upp till 13% i juni då man jämför scenariot att bara ladda elbilar och ha stationärt batteri med scenariot V2B med hänsyntill batteriladdningskostnad 80 öre/kWh.
63

Field Testing the Effects of Low Reynolds Number on the Power Performance of the Cal Poly Wind Power Research Center Small Wind Turbine

Cunningham, John B 01 December 2020 (has links) (PDF)
This thesis report investigates the effects of low Reynolds number on the power performance of a 3.74 m diameter horizontal axis wind turbine. The small wind turbine was field tested at the Cal Poly Wind Power Research Center to acquire its coefficient of performance, C­p, vs. tip speed ratio, λ, characteristics. A description of both the wind turbine and test setup are provided. Data filtration and processing techniques were developed to ensure a valid method to analyze and characterize wind power measurements taken in a highly variable environment. The test results demonstrated a significant drop in the wind turbine’s power performance as Reynolds number decreased. From Re = 2.76E5 to Re = 1.14E5, the rotor’s Cp_max changed from 0.30 to 0.19. The Cp vs. λ results also displayed a clear change in shape with decreasing Reynolds number. The analysis highlights the influence of the rotor’s Cl /Cd characteristics on the Cp vs. λ curve’s Reynolds number dependency. By not accounting for the effects of varying Reynolds number below the critical value for a rotor operating at constant λ, the design of the rotor planform may overestimate the actual performance of the turbine in real-world conditions. This problem is more evident in distributed-scale wind turbines, compared to utility-scale ones, because of the significantly shorter chord lengths, and therefore increased wind speed range where this effect occurs. Lastly, the wind turbine’s future control method and annual energy production are evaluated using the test results.
64

Relay settings for frequency derivative protection against islanding : Optimizing RoCoF-Hysteresis and Delay for the Swedish power grid: An investigation of relevant values / Reläinställningar för frekvensderivataskydd mot ödrift : Optimering av RoCoF-Hysteres och Fördröjning för det svenska elnätet: En undersökning för relevanta värden

Safari, Ahmad January 2023 (has links)
This report addresses the parameter settings for a protective relay designed to safeguard a 15 kW wind turbine located in Rimbo, Norrtälje municipality, against unintentional islanding. This type of situation arises when distributed energy resources continue to supply local loads, even if the main grid has been unintentionally disconnected. The previous protection system experienced malfunctions and has been replaced with a new protective relay to ensure reliable protection. The new protective relay introduces two parameters (relay settings) associated with unintentional islanding protection function, namely RoCoF (rate of change of frequency) hysteresis, and delay, which were not defined in the previous protective relay. This report aims to determine suitable relay settings and verify that the relay operates as intended, taking into account both local and national requirements for connected generators. When these requirements did not specify or recommend a specific value, reference was made to practices in neighbouring countries, and consideration was given to the generator owner's benefit. Testing the relay with the chosen settings was crucial to ensure a correct understanding and accurate input of the settings. The testing was conducted in a laboratory environment with carefully defined signals of controlled frequency and voltage, while the relay's trip output was logged. The report includes information about the current settings along with a theoretical background to explain their functionality. It also presents test results and the provided information on parameter configurations. Additionally, recommended settings for RoCoF hysteresis and implementation delay are suggested, aiming to enhance protection against inadvertent operation. The results confirmed that the relay can be used in Rimbo, Norrtälje municipality, according to the parameters described in the report. / Denna rapport behandlar parameterinställningar för ett skyddsrelä som skyddar en 15 kW vindkraftsturbin i Rimbo, Norrtälje kommun, mot oavsiktlig ödrift. Denna typ av situation uppstår när distribuerade energiresurser försätter att mata lokala laster, även om stamnätet har kopplats bort oavsiktlig. Det tidigare skyddssystemet har blivit skadat och ersatt med ett nytt skyddsrelä för att säkerställa ett tillförlitligt skydd. Det nya skyddsreläet introducerar två parametrar (reläinställningar) relaterade till skyddsfunktionen mot oavsiktlig ödrift, nämligen RoCoF (frekvensderivata intervall) hysteres och fördröjning, som inte var definierade i det tidigare skyddsrelät. Denna rapport syftar till att fastställa lämpliga reläinställningar och verifiera att reläet fungerar enligt avsikt, med hänsyn till både lokala och nationella krav för anslutna generatorer. När dessa krav inte specificerade eller rekommenderade ett specifikt värde, refererades det till praxis i närliggande länder och hänsyn togs till generatorägarens fördel. Testning av reläet med de valda inställningarna var av central betydelse för att säkerställa en korrekt förståelse och korrekt inmatning av inställningarna. Testningen utfördes i en laborationsmiljö med noggrant definierade signaler av kontrollerad frekvens och spänning, samtidigt som reläets utlösningsutgång loggades.  Rapporten inkluderar information om de aktuella inställningarna tillsammans med en teoretisk bakgrund för att förklara deras funktion. Den presenterar också resultat från tester och den tillhandahållna informationen om parameterinställningar. Dessutom rekommenderas inställningar för RoCoF-hysteres och fördröjning för implementering, med målet att förbättra skyddet mot oavsiktlig ödrift. Resultaten konstaterade att reläet kan användas i Rimbo, Norrtälje kommun enligt de parametrar som beskrivs i rapporten.
65

A Cooling, Heating, And Power For Buildings (Chp-B) Instructional Module

Hardy, John David 10 May 2003 (has links)
An emerging category of energy systems, consisting of power generation equipment coupled with thermally-activated components, has evolved as Cooling, Heating, and Power (CHP). The application of CHP systems to buildings has developed into a new paradigm ? Cooling, Heating, and Power for Buildings (CHP-B). This instructional module has been developed to introduce undergraduate engineering students to CHP-B. In the typical ME curriculum, a number of courses could contain topics related to CHP. Thermodynamics, heat transfer, thermal systems design, heat and power, alternate energy systems, and HVAC courses are appropriate for CHP topics. However, the types of material needed for this mix of courses vary. In thermodynamics, basic problems involving a CHP flavor are needed, but in an alternate energy systems course much more CHP detail and content would be required. This series of lectures on CHP-B contains both a stand-alone CHP treatment and a compilation of problems/exercises.
66

Sizing Methodology and Life Improvement of Energy Storage Systems in Microgrids

Khasawneh, Hussam Jihad 19 May 2015 (has links)
No description available.
67

Microgrid Optimal Power Flow Based On Generalized Benders Decomposition

Jamalzadeh, Reza 02 February 2018 (has links)
No description available.
68

A Simulation Platform to Demonstrate Active Demand-Side Management by Incorporating Heuristic Optimization for Home Energy Management

Gudi, Nikhil 09 September 2010 (has links)
No description available.
69

Control of distributed energy storage and EVs in building communities

Zigga, Kweku, Nasir, Usman January 2023 (has links)
This study delves into the comparative operational effectiveness of non-coordinated, bottom-up, and top-down coordinated control models within Distributed Energy Storage Systems (DESS) and Electric Vehicle (EV) networks. Employing meticulous data analysis, this research evaluates power demand and supply dynamics within the infrastructure and buildings, aiming to optimize energy usage and storage. The analysis involves comprehensive steps: descriptive statistical breakdown, understanding energy patterns across buildings, and a comparative assessment of the control models. Visual representations and graphs aid in depicting energy patterns, emphasizing the distinctive characteristics and effectiveness of each control model. The findings reinforce the superiority of the top-down coordinated control model in managing supply-demand imbalances, echoing established literature.
70

Grid Tariff Design for Efficient Utilisation of the Distributor Grid : A qualitative study with actors on the Swedish electricity market

Haikola, Matilda, Söderberg, Malin January 2020 (has links)
The Swedish electricity system is transitioning due to the establishment of climate policy goals and trends related to technology and demographics. The transition has resulted in an increased demand for electricity. The increased demand for electricity in combination with lack of forecasts, planning and coordination between actors in the electricity sector has led to the occurrence of grid congestion. Extending the network is time-consuming and requires substantial investments. Instead, an alternative is to utilise the available grid capacity more efficiently by implementing flexibility solutions. Flexibility can be achieved by implementing incentives such as grid tariffs. This solution has recently gained much attention in Sweden, but it is not apparent how grid tariffs should be designed. The purpose of this thesis is to investigate how distribution grid tariffs could be designed to incentivise different actors to contribute to flexibility in a way that results in an efficient use of the electrical grid. A qualitative study was performed, collecting empirical data through semistructured interviews with actors in the Swedish electricity market. The aim is that the results from this thesis will act as a basis for DSOs planning to design grid tariffs with the purpose to utilise the grid more efficiently. The findings present a ToU capacity charge with off-peak periods that are free of charge as the preferable main price signal in the tariff to achieve efficient utilisation of the grid. It is further argued that other structural elements can complement the ToU capacity charge. A small fixed charge could be added in order to contribute to the cost reflectiveness of the grid tariff. A small energy charge could be incorporated in order to provide consumer with incentives to be flexible below the current metered maximum power and strengthen the signal from the ToU capacity charge. A small energy charge can avert difficulties related to providing incentives below the current metered maximum, as it still can provide some incentives to be flexible, or strengthen the signal from the ToU capacity charge. Further, the energy charge can ensure sustainability if customers respond well to a ToU capacity charge and to compensate solar PV customers. Furthermore, recommendations to further enable the grid tariffs potential to provide price signals include shifting the focus of the revenue cap from CapEx to OpEx and exploring the hampering signals of the energy tax as well as contradicting price signals from the wholesale electricity price. / Det svenska elsystemet genomgår en förändring till följd av införandet av klimatmål och trender relaterade till teknik och demografi. Denna förändring har resulterat i ett ökat effektbehov. Ett ökat effektbehov i kombination med bristande prognostisering, planering och samordning mellan aktörer inom elsektorn har lett till uppkomsten av kapacitetsbrist. Att bygga ut elnätet är tar tid och kräver större investeringar. Ett alternativ är att istället utnyttja det befintliga elnätet mer effektivt genom att implementera flexibilitetslösningar. Flexibilitet kan uppnås genom att införa incitament i form av elnätstariffer. Denna lösning har nyligen fått mycket uppmärksamhet i Sverige, men det är inte klart inte hur dessa elnätstariffer ska utformas. Syftet med detta arbete är att undersöka hur distributionsnätets tariffer kan utformas för att stimulera olika aktörer att bidra med flexibilitet på ett sätt som resulterar i en effektiv användning av det befintliga elnätet. En kvalitativ studie genomfördes där empiriska data samlades in genom semistrukturerade intervjuer med aktörer på den svenska elmarknaden. Syftet är att resultaten från detta arbete ska fungera som ett underlag för nätägare som planerar att utforma elnätstariffer med syftet att utnyttja nätet mer effektivt. Resultaten visar att en ToU-effektavgift med gratis off-peak perioder bör vara den huvudsakliga prissignalen i en elnätstariff som ämnar att utnyttja det befintliga nätet mer effektivt. Det visar även att andra strukturella element kan komplettera ToU-effektavgiften. En mindre fast avgift kan adderas i syfte att göra elnätstariffen mer kostnadsriktig. En mindre energiavgift kan införas för att ge kunder incitament att vara flexibla även under den nuvarande uppmätta maximala effekten och stärka signalen från ToU-effektavgiften. Vidare kan energiavgiften säkerställa tillräckliga intäkter för nätägaren om kunderna svarar bra på en ToU-effektavgift och för att kompensera kunder med solceller. Ytterligare rekommendationer för att möjliggöra prissignaler genom elnätstariffer inkluderar att skifta fokus på intäktsramen från CapEx till OpEx och utforska de hämmande prissignalerna från energiskatten och de motstridiga prissignalerna från elhandelspriset.

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