Дисертації з теми "Simulation accuracy in power engineering"
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1
Mesbahi, Abdessamad. "Deterministic and Stochastic Economic Modeling of Hybrid Power Supply System with Photovoltaic Generators." Master's thesis, КПІ ім. Ігоря Сікорського, 2021. https://ela.kpi.ua/handle/123456789/42555.
Повний текст джерелаАнотація:
Relevance of research. Due to the rapid deployment of the non-dispatchable (intermittent) generation sources in the smart grid, such as integration of the photovoltaic power plants and wind turbines in the distribution systems; this caused a problem of the uncertainty increase of simulation results for decision-making for power supply systems, these uncertainties of power systems are getting more and more notice. At the same time, the classical power systems models cannot give accurate simulation results. Wherein; it became necessary to define new models to represent the specific parameters of power system. wherein; this research reveals to the benefits of using probabilistic mathematical approaches to define and calculate the specific economic parameters, as well as the technical parameters for power supply system with the integration renewable energy generators, which are characterising by randomness and uncertainty due to the high penetration to the renewables. Monte Carlo Method, and Point Estimation Method are used to handle the uncertainties of renewable energy resources. The standard functions to represent the stochastic parameters of the model are analyzed with the use of three-point estimation technique for the distribution functions of their probable values. A synthetic skewed probability density function was analytically constructed basing on the standard normal distribution, which is suitable for analytic representation of the predicted and/or statistical random sampling of the uncertain model parameters of energy system with renewables, and analytical expressions were obtained to compute the moments of proposed synthetic probability function.
Relationship of work with scientific programs, plans, themes. is to demonstrate the possibility of describing the input parameters of the simulation Deterministic and Stochastic Modeling by probability Density Functions by the use of three-point approximation techniques and to obtain analytical expressions for the characteristics of such distributions, suitable for non-iterative (as opposed to Monte Carlo Method) probabilistic method applications, namely the Point Estimation Method.
Purpose and tasks of the research. Increasing the simulation accuracy results for estimation economic and technical parameters characterising photovoltaic power plant based on based on the life cycle model; as well as development of different algorithms based on deterministic and stochastic modeling of power system with non-dispatchable sources and minimize the computation time.
Object of research. Processes of determining the estimated technical and economic parameters characterising a photovoltaic power plant located in Ukraine basing on stochastic modeling.
Subject of research. Use of the Monte Carlo Method and Point Estimation Method to estimate the various economic and technical information characteristic of alternative power plants in order to obtain accurate simulation results.
Practical value of the results. Practical techniques of the three-point approximation are used to construct the probability density function of the model uncertain (stochastic) parameter, which dominantly influences the modeling result: an event occurrence probability, the result attainability, whatsoever. This technique is an effective tool for the practical evaluating of an uncertain value of a technological or economic factor of material and/or economic object, and widely used for overall Levelized Energy Cost (LCOE – LEC) which is directly or indirectly engaged into analytic representation of the power systel model. Usually, the model of a kind is designed to solve technical and/or economic problem by means of Deterministic and Stochastic Modeling.
Scientific novelty of the obtained results is the development of algorithms and mathematical solutions using a probabilistic approach basing Point Estimation Method instead of Monte Carlo Melthod to obtain more accurate estimation simulation results, as well as to obtain computational results in less time for useful decision-making in alternative power plant projects.
2
Jarmander, Sara. "Wind Power Forecast Accuracy in Scandinavia:Analysis of Forecast Errors Using TAPM." Thesis, KTH, Kraft- och värmeteknologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-226146.
Повний текст джерелаАнотація:
Wind power has different characteristics compared to conventional energy sources. The main difference is that wind power fluctuates under the influence of meteorological variables. This gives rise to problems related to grid stability. It is therefore important to understand these variations and their predictability in order to improve the integration of wind power into grids. Wind power forecasts play an important role. In this study, the accuracy of Numerical Weather Prediction (NWP) wind speed forecasts over the period 1st Sept. 2013 – 31st Dec. 2016 has been investigated. This was done for four Scandinavian windfarms; Rødsand II, Kårehamn, Jokkmokksliden and Storliden. The NWP used was The Air Pollution Model (TAPM). The main aim of the study was to examine if the implementation of bias correction methodologies could improve the accuracy of uncorrected TAPMforecasts. In addition to this main aim, the study was also intended to investigate the differences in the performance of TAPM between Australian and Scandinavian weather conditions. The results indicated that TAPM has a tendency to under-predict against actual observations. It was also observed that the accuracy varied throughout the year, with the best performance during summer and the worst during winter. Additionally, the performance varied between turbines within the wind farms. The magnitude of forecast errors was lowest for turbines which experience high degrees of wake effects from upstream turbines. Furthermore, the results showed that the implementation of certain bias correction methodologies improved the accuracy. The greatest enhancements were achieved by the implementation of two correction methodologies, both based on the combination of bias correction and timing correction. The NRMSE of wind speed was reduced by almost 50% for “hour ahead” forecasts for Rødsand II and Kårehamn when full bias correction was applied and by nearly 70% for Jokkmokksliden and Storliden. A reduction in the wind speed magnitude error by as much as half was also reached. Based on these results, the overall conclusion is that TAPM can be applied for sites with completely different weather conditions with moderately good accurateness, especially if bias correction is applied. However, due to the limited time frame and other delimitations of this study, further studies are necessary in order to draw deeper conclusions.Vindkraft är en förnybar energikälla som skiljer sig på flera sätt jämfört med konventionell energiproduktion. Konvensionell produktion avser planerbar och icke väderberoende energiproduktion som dessutom är synkront kopplad till elnätet, exempelvis vattenkraft och kärnkraft. Den huvudsakliga skillnaden är att energiproduktionen från vindkraftverk är direkt kopplad till meteorologiska förhållanden och är därmed beroende av de rätta väderbetingelserna för att kunna producera el, framförallt rådande vindhastigheter. Detta innebär att elproduktionen varierar på ett oförutsägbart sätt vilket medför att den producerade elkraften från vindkraftverk är mindre stabil jämfört med elkraft som utnyttjar konventionells krafttekniker. En ökad andel variabel elproduktion från vindkraft medför stora utmaningar för det befintliga och framtida kraftsystemet. Den främsta utmaningen är att upprätthålla balansen i systemet, både i det korta och långa tidsperspektivet. Om inga åtgärder genomförs förväntas kraftsystemets utformning och egenskaper att bli sämre i form av ökad känslighet för störningar och försämrad leveranstid. En ökad förståelse för vindkraftsproduktionens variabilitet och förutsägbarhet är därmed av intresse för att kunna förbättra integrationen av variabel vindkraftsproduktion. Prognosmodeller för vindkraftsproduktion (analogt med prognoer för vindhastighet) utgör en viktig faktor i detta. I denna studie har noggrannheten av numeriska väderprognoser (NWP) analyserats. Analysen genomfördes för fyra skandinaviska vindkraftparker mellan 1 september 2013 och 31 december 2016. De granskade parkerna var: Rødsand II, Kårehamn, Jokkmokksliden och Storliden. Den numeriska prognosmodell som används i denna studie var The Air Pollution Model (TAPM). TAPM utvecklades i Australien och modellen bygger på observationsbaserade meterologiska input. TAPM är i själva verket ansluten till globala databaser med struktuerad meterologisk data bestående av bland annat terränghöjd, vegetation och synoptisk metrologisk information. TAPM har tidigare tillämpats för att förutspå vindhastigheter för ett flertal vindkraftparker i Australien och ett antal platser i USA. Inga tidigare studier har dock gjorts för scandinaviska förhållanden. Det huvudsakliga målet med denna studie var därmed att undersöka huruvida biaskorrigerade metoder kan förbättra noggrannheten av okorrigerade TAPMprognoser för de fyra utvalda vindkraftparkerna. Denna studie avsåg även att undersöka om prognosernas noggrannhet skiljer sig nämnvärt mellan skandinaviska och australienska väderförhållanden. Numeriska modeller innehåller alltid fel jämför med de ”sanna” värdena. Resultatet av denna studie indikerade att TAPM-prognoserna har en tendens att underskatta vindhastigheter, därmed även vindkraftsproduktionen gentemot den verkliga produktionen. Dessutom observerades att prognosernas noggrannhet varierade under året. Den bästa tillförlitligheten erhölls under vintern och den sämsta tillförlitligheten under sommarhalvåret. Vidare varierade prognosernas noggrannhet mellan turbinerna inom de enskilda vindkraftparkerna. Storleken på felet i TAPMprognoserna var generellt sett lägst för turbiner som utsetts för så kallade vakar. Vakar är ett fenomen som uppstår bakom rotorbladen och påverkar energiproduktionen för bakomliggande vindkraftverk. Storleken på felet var lägst för turbiner som i stor utsträckning påverkas av vakar från turbiner uppströms. Resultatet visade även att implementeringen av biaskorrigerande metoder förbättrade noggrannheten av TAPM-prognoserna. Sammantaget undersöktes fyra biaskorrigerande metoder varav två uppvisade de största förbättringarna. Gemensamt för dessa två metoder var att de baserades på en kombination av biaskorrigering och tidskorrigering. Olika statistiska metoder användes för att uppskatta storleken av felet för den förutspådda vindhastigheten som modellerats i TAPM. Bland annat användes Root Mean Square Error (RMSE), Mean Absolute Error (MAE) och Mean Bias Error (MBE). Dessa värden normaliserades därefter med avseende på medelvärdet av den verkliga produktionen för önskad tidsperiod. Resultatet visade bland annat att NRMSE för TAPM-modellerade timvisa vindhastigheter minskade med nästan 50 % för Rødsand II och Kårehamn när full biaskorrektion tillämpades och med uppemot 70 % för Jokkmokksliden och Storliden. Med utgångspunkt från de erhållna resultaten är den övergripande slutsatsen att TAPM kan tillämpas för geografiska platser med olika väderförhållanden och samtidigt generera prognoser med relativt god noggrannhet, speciellt om biaskorrigerade metoder appliceras. Till följd av den begränsande tidsramen och andra avgränsningar i denna studie är dock ytterligare analyser nödvändiga för att dra djupare slutsatser.
3
McCoy, Timothy J. (Timothy John). "Dynamic simulation of shipboard electric power systems." Thesis, Massachusetts Institute of Technology, 1993. http://hdl.handle.net/1721.1/12495.
Повний текст джерела
4
Bras, Johan J. "A simulation of the single scan accuracy of a two-dimensional pulsed surveillance radar." Master's thesis, University of Cape Town, 1991. http://hdl.handle.net/11427/8460.
Повний текст джерелаАнотація:
Bibliography: leaves 194-198.The following dissertation considers the single-scan two-dimensional positional accuracy of a pulsed surveillance radar. The theoretical aspects to the positional accuracy are considered and a generalized analytical approach is presented. Practical position estimators are often complex, and theoretical predictions of their performance generally yield unfriendly mathematical equations. In order to evaluate the performance of these estimators, a simulation method is described based on replicating the received video signal. The accuracy of such a simulation is determined largely by the accuracy of the models applied, and these are considered in detail. Different azimuth estimation techniques are described, and their performances are evaluated with the aid of the signal simulation. The best azimuth accuracy performance is obtained with the class of analogue processing estimators, but they are found to be more susceptible to interference than their binary processing counterparts. The class of binary processing estimators offer easily implemented techniques which are relatively insensitive to radar cross-section scintillation characteristics. A hybrid estimator, using both analogue and binary processing, is also evaluated and found to give an improved accuracy performance over the binary processing method while still maintaining the relative insensitivity to radar cross-section fluctuation.
5
Picard, Yani. "Improving the precision and accuracy of Monte Carlo simulation in positron emission tomography." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=68241.
Повний текст джерелаАнотація:
PETSIM, a Monte Carlo simulation program of Positron Emission Tomography (PET) systems, was improved in terms of accuracy and efficiency. First, the accuracy, the speed and the ease of use of PETSIM were improved by using tabulated values of the Compton scattering and photoelectric absorption partial interaction attenuation coefficients for all common biological, collimator and detector materials. These were generated from chemical formula, or physical composition, and density of the absorbing medium.Furthermore, simulations of PET systems waste considerable time generating events which will never be detected. For events in which the original photons are usually directed towards the detectors, the efficiency of the simulations was improved by giving the photons additional chances of being detected. For simulation programs which cascade the simulation process into source, collimation, and detection phases such as PETSIM, the additional detections resulted in an improvement in the simulation precision without requiring larger files of events from the source/phantom phase of the simulation. This also reduced the simulation time since fewer positron annihilations were needed to achieve a given statistical precision. This was shown to be a useful improvement over conventional Monte Carlo simulations of PET systems.
6
Ramos, Calderón Antonio José. "Computational and accuracy benchmarking of simulation and system-theoretic models for production systems engineering." Thesis, Högskolan i Skövde, Institutionen för ingenjörsvetenskap, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:his:diva-19877.
Повний текст джерелаАнотація:
The modern industry has an increasing demand for simulation software able to help workers and decision-makers visualize the outputs of a specific process in a fast, accurate way. In this report, a comparative study between FACTS (Factory Analyses in ConcepTual phase using Simulation), Plant Simulation, and PSE (Production System Engineering) Toolbox is done regarding their capacity to simulate models with increasing complexity, how accurate they are in their outputs with different optimized buffer allocations, and how well they perform on the task of detecting the bottlenecks of a process. Benchmarking simulation software requires an experimental approach, and for gathering and organizing all the data generated using external programs like MATLAB, C, Excel, and R are used. A high level of automatization is required as otherwise the manual input of data would take too long to be effective.The results conclude on major concordances among FACTS and Plant Simulation as the most used commercial DES (Discrete Event Simulation) software and a more mathematical-theoretical approach coming from PSE Toolbox. The optimization done in the report links to sustainability, with an enhanced TH improving the ecological, social and economic aspects, and to Lean philosophy using lean buffers that smooth and improve the production flow.
7
Khalil, Louay. "LoRa-positioning in Malmö compared with GPS: possibilities, power consumption & accuracy." Thesis, Malmö universitet, Fakulteten för teknik och samhälle (TS), 2018. http://urn.kb.se/resolve?urn=urn:nbn:se:mau:diva-20479.
Повний текст джерелаАнотація:
Internet of Things, blir allt större för varje dag och talas om överallt där teknik är närvarande.Större företag implementerar idéer och lösningar som är bundna till IoT, ochmindre företag följer trenden med att följa tekniska lösningar med låg strömförbrukningoch långsiktig täckning av signal. LoRaWAN möjliggör just det och utvecklas mycketsnabbt för bättre användning och bättre lösningar. Numera utvecklar och forskar företagenmycket i lösningar för smarta spårningsobjekt och i detta dokument byggs en prototypför att spåra stulna cyklar där positionsspårning experimenteras med. GPS-spårning jämförsmed LoRaWAN-spårning efter att en prototyp har byggts och utformats för att spåraen stulen cykel med båda lösningarna. Syftet med denna avhandling är att visa hur ensådan prototyp kan byggas och vad resultaten är mellan GPS-spårningen och LoRaWANspårningen.Detta koncept ger en förståelse av hur långt utvecklingen av LoRaWAN-näthar nått i en stad som Malmö i Sverige. Ena fallscenariot visar resultat av prototypensenergiförbrukning utan att cykeln stulits. Ett andra scenario visar när cykeln är stulen ochpresenterar skillnaderna i strömförbrukningen och lokaliseringens noggrannhet. I scenario1 GPS-positionering varar i 12 dagar medan LoRaWAN-positionering varar 14 dagar. Iscenario 2 är resultaten 9 dagar mot 14 dagar för GPS gentemot LoRaWAN.Internet of Things is becoming bigger for each day and is talked about everywhere technologyis present. Major companies are implementing ideas and solutions bound to theIoT and smaller companies are following the trend in pursuing technological solutions withlow power consumption and long range coverage of signal. LoRaWAN enables just thatand is getting developed very fast for better usage and better solutions. Nowadays, companiesdevelop and research a lot in solutions for smart tracking objects and in this papera prototype to track stolen bicycles is built where tracking is experimented with. GPStrackingis compared to LoRaWAN-tracking after a prototype is been built and designedto track a stolen bicycle with both solutions. The aim for this thesis is to show how suchprototype can be built and what the results are between GPS-tracking and LoRaWANtracking.This concept gives an understanding of how far the development of LoRaWANnetworks has reached in a city like Malmö in Sweden. One case scenario shows results ofthe prototype used in reality without having the bicycle stolen. A second scenario showswhen the bicycle is stolen and presents the differences in the results of power consumptionand accuracy of localization. In case scenario 1 GPS-positioning lasts for 12 days whileLoRaWAN-positioning lasts 14 days. In case scenario 2 the results are 9 days against 14days.
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Beatty, Debra Ann Kemnitz. "Simulation of a family of DC-to-DC power supplies." Honors in the Major Thesis, University of Central Florida, 1995. http://digital.library.ucf.edu/cdm/ref/collection/ETH/id/137.
Повний текст джерелаАнотація:
This item is only available in print in the UCF Libraries. If this is your Honors Thesis, you can help us make it available online for use by researchers around the world by following the instructions on the distribution consent form at http://library.ucf.edu/Systems/DigitalInitiatives/DigitalCollections/InternetDistributionConsentAgreementForm.pdf You may also contact the project coordinator, Kerri Bottorff, at kerri.bottorff@ucf.edu for more information.Bachelors
Engineering
Electrical Engineering
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Jaworsky, Christina A. "The effects of energy storage properties and forecast accuracy on mitigating variability in wind power generation." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/81605.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2013.Cataloged from PDF version of thesis.
Includes bibliographical references (p. 84-87).
Electricity generation from wind power is increasing worldwide. Wind power can offset traditional fossil fuel generators which is beneficial to the environment. However, wind generation is unpredictable. Wind speeds have minute to minute variability which causes minute to minute generation to fluctuate. Additionally, wind forecasting does not perfectly predict wind generation, so it is difficult for wind to meet a generation schedule. Therefore, with increased wind production, there is a need for flexibility in the electricity grid. Electricity storage is one method of achieving greater flexibility. With storage, wind generators can have a less variable power output. They can also be made to follow a generation schedule the same way traditional generation does. This study discusses the storage requirements for reducing the variability of wind power. It also assesses the value of an accurate forecast in terms of storage requirements. Storage capacity requirements are shown to be modest compared to the size of a generator, representing approximately one minute of full power generation capacity. Accurate forecasting can reduce the storage requirements of a wind generator. However, forecasts have little added value for greater accuracy beyond correctly predicting the mean of the wind generation on delivery scheduling intervals.
by Christina A. Jaworsky.
S.M.
10
Chan, Chunwa. "Design, simulation and analysis of RESURF Si/SiC power LDMOSFETs." Thesis, University of Warwick, 2018. http://wrap.warwick.ac.uk/102005/.
Повний текст джерелаАнотація:
It is necessary for power laterally diffused MOSFETs (LDMOSFETs) to operate efficiently and reliably in high temperature (< 300 °C), hostile environments such as those found in downhole, space, automotive and aerospace applications. Currently, silicon-oninsulator (SOI) technology is a dominant method to achieve this goal due to low leakage current and complete electrical isolation. However, the buried oxide (BOX) layer causes self-heating, which can impact device performance, cause thermal runaway and shorten device lifetime. To address this issue, one solution is to combine a silicon thin film with a semi-insulating (SI) SiC substrate, forming the Si/SiC architecture. LDMOSFETs built on this substrate are expected to deliver much better thermal performance, with electrical isolation comparable to the SOI case. However, the Si/SiC LDMOSFETs do not have a strong substrate assisted depletion effect, which can result in poorer electrical performance than those of the Reduced Surface Field (RESURF) bulk-Si and SOI LDMOSFETs. This thesis investigates the PN and SOI RESURF layouts and uses them to optimise 190 V and 600 V Si/SiC LDMOSFETs. DC and transient modelling will be conducted on the optimised Si/SiC and their SOI and bulk-Si equivalents. Based upon this, several comparative studies are conducted on their simulation results to see the effects of the Si/SiC architecture on the LDMOS designs. The comparative studies are made on the 600 V Si/SiC LDMOSFETs and their bulk Si and SOI equivalents. It is shown that the Si/SiC devices have the potential to operate with an off-state leakage current as low as the SOI device. However, the low-side resistance of the SOI LDMOSFET is smaller in value and less sensitive to temperature, outperforming both Si/SiC devices. Conversely, under high-side configurations, the Si/SiC transistors have resistances lower than that of the SOI at high substrate bias, and invariable with substrate potential up to −200 V, which behaves similar to the bulk-Si LDMOS at 300 K. A clamped-inductive switching circuit is simulated for the Philips SOI and the Si/SiC equivalent. It is shown that even though the SOI has a smaller chip area and suffered from strong substrate effects during the transient state, the two devices had similar currents and power dissipations at the gate, drain and source. The turn-on losses are higher than that of the turn-off losses due to the presence of parasitic capacitors. However, these similarities do not lead to similar thermal responses in both devices and the SOI is heated up at a much faster rate. By contrast, the SiC substrate in the Si/SiC behaves like an embedded heat sink regulating device temperature close to that of the ambient environment (423 K). In the high current condition, the peak temperature in the Si/SiC is 425 K, lower than 463 K in the SOI, thereby increasing reliability. The comparative studies are carried out on the 190 V LDMOSFETs in SOI, Si/SiC, Partial SOI (PSOI) and PSOSIC technology, based upon a capacitive and an inductive switching circuit. It is revealed that in spite of having a chip area 75% larger than the SOI structure, the Si/SiC solution undergoes negligible heating in any of the switching conditions simulated, exhibiting a very high energy capability. By contrast, the 22% area increase in the PSOSiC does not considerably change the way the energy is handled. This indicates that the Si/SiC is much more effective than PSOI and PSOSIC in dealing with the transient heating.
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Kumar, Yogesh. "Study of Power and Renewable Systems Modeling and Simulation Tools." University of Toledo / OhioLINK, 2015. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1449868982.
Повний текст джерела
12
Gervais, Renaud. "Towards High-Accuracy Augmented Reality GIS for Architecture and Geo-Engineering." Thesis, Université Laval, 2012. http://www.theses.ulaval.ca/2012/28989/28989.pdf.
Повний текст джерелаАнотація:
L’architecture et la géo-ingénierie sont des domaines où les professionnels doivent prendre
des décisions critiques. Ceux-ci requièrent des outils de haute précision pour les
assister dans leurs tâches quotidiennes. La Réalité Augmentée (RA) présente un excellent
potentiel pour ces professionnels en leur permettant de faciliter l’association des
plans 2D/3D représentatifs des ouvrages sur lesquels ils doivent intervenir, avec leur
perception de ces ouvrages dans la réalité. Les outils de visualisation s’appuyant sur
la RA permettent d’effectuer ce recalage entre modélisation spatiale et réalité dans le
champ de vue de l’usager. Cependant, ces systèmes de RA nécessitent des solutions de
positionnement en temps réel de très haute précision. Ce n’est pas chose facile, spécialement
dans les environnements urbains ou sur les sites de construction. Ce projet
propose donc d’investiguer les principaux défis que présente un système de RA haute
précision basé sur les panoramas omnidirectionels.Architecture and geo-engineering are application domains where professionals need to take critical decisions. These professionals require high-precision tools to assist them in their daily decision taking process. Augmented Reality (AR) shows great potential to allow easier association between the abstract 2D drawings and 3D models representing infrastructure under reviewing and the actual perception of these objects in the reality. The different visualization tools based on AR allow to overlay the virtual models and the reality in the field of view of the user. However, the architecture and geo-engineering context requires high-accuracy and real-time positioning from these AR systems. This is not a trivial task, especially in urban environments or on construction sites where the surroundings may be crowded and highly dynamic. This project investigates the accuracy requirements of mobile AR GIS as well as the main challenges to address when tackling high-accuracy AR based on omnidirectional panoramas.
13
Canales, Severiano R. (Severiano Rene). "Development of a reusable practice device to measure the power, accuracy, and placement of a golf shot." Thesis, Massachusetts Institute of Technology, 2005. http://hdl.handle.net/1721.1/32873.
Повний текст джерелаАнотація:
Thesis (S.B.)--Massachusetts Institute of Technology, Dept. of Mechanical Engineering, 2005.Includes bibliographical references (leaf 17).
The purpose of this thesis was to develop a reusable practice device that could help golfers analyze their shots. A Magic Pad, consisting of a translucent, plastic top layer and a statically charged thin layer of cardboard, was modified and placed on the clubface. When the clubface strikes the ball, the top plastic layer attaches itself to the bottom layer creating a noticeable impression. By peeling the top layer, the device could be reset and used again several times. A series of tests was conducted to prove the viability of this device. The device was effective in analyzing several aspects of a golf shot. The marks made on the device from impact with the ball were clear and dark. This device is most effective in determining the placement of the ball on the clubface, but it is also successful in identifying inaccurate shots. Slices occur when the club head does not hit the ball squarely, and this is translated unto the device. A few characteristic marks signal a slice. The most obvious is a mark with amorphous shape, favoring one side of the ball, instead of a circular indentation. Shear streaks, straight diagonal lines at the angle of impact, are also apparent and allow the golfer to adjust their swing to compensate.
(cont.) The third aspect of the shot that the device could have measured was the power. A bigger indentation did not necessarily produce the greatest yardage, however. The most impressive indentations were produced by a combination of accuracy and power. In this way, the golfer can clearly identify a quality shot. This fact, coupled with the inexpensive materials, makes the device a viable product.
by Severiano R. Canales.
S.B.
14
Yang, Conghuan. "Real-time FPGA-based co-simulation of large scale power systems." Thesis, University of Birmingham, 2018. http://etheses.bham.ac.uk//id/eprint/8037/.
Повний текст джерелаАнотація:
With the rapid increase of size and complexity of modem electrical power systems, 1) the simulation accuracy and 2) the capability of simulating large power systems have become two conflicting objectives. This thesis proposes a novel FPGA-RTDS co-simulator to meet these two objectives. As the basis of the co-simulator, a library of power system components is developed in FPGA, including the most commonly used power system elements and control systems. The proposed cosimulator combines the advantages of 1) the paralleled architecture, high logic density and high clock speed from FPGA and 2) better modelling flexibility and user-friendly GUI from RTDS together. Multi-FPGA structure is introduced to further improve the simulation capability for large power systems. The use of detailed EMT models in the whole system guarantees the accuracy of simulation and eliminates the potential interface error. Deeply pipelined and massively paralleled algorithms have been designed to maximize time and hardware efficiency. The modular design significantly improves the system expandability. Case studies including large scale power system with more than 4000 nodes are presented to demonstrate the simulation capability. Comparisons are made with SIMULINK and RTDS to verify the accuracy of the proposed co-simulator.
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Cristaldo, Nelson. "Secure power grid infrastructure simulation and test-bed system creation." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/2668.
Повний текст джерелаАнотація:
This thesis describes the design and construction of the test-bed system as well as its implementation to simulate the distributed control scheme. Some important elements of the system incorporate flexible power system network hardware and a data acquisition (DAQ) system to evaluate the issues that could trigger cascaded failures.
The objective of this research was to create an integrated simulation environment that represents the power system devices, the control, the protection, and the communication subsystems in the same simulation environment. We have utilized this simulator to conduct system studies and evaluate the interaction between power system components under steady-state and transient operation. The results of these studies have been used to enhance the system's ability to identify, and respond to the system's dynamic transients; improving the survivability and robustness of the power system during and after a disturbance by utilizing distributed control strategies. Experiments demonstrated in this thesis show the applicability of the developed simulator to conduct system studies and to evaluate the proposed distributed control infrastructure. The results show the advantages of utilizing distributed control and the impact in the system security and reliability.
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Brown, Eric C. "Estimates of statistical power and accuracy for latent trajectory class enumeration in the growth mixture model." [Tampa, Fla.] : University of South Florida, 2003. http://purl.fcla.edu/fcla/etd/SFE0000622.
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Westin, Fredrik. "Simulation of turbocharged SI-engines - with focus on the turbine." Doctoral thesis, Stockholm, 2005. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-216.
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Deeter, Thomas Lieutenant(Thomas Andrew). "Creating a shipboard power simulation tool using electrical load behavior modeling." Thesis, Massachusetts Institute of Technology, 2020. https://hdl.handle.net/1721.1/127040.
Повний текст джерелаАнотація:
Thesis: Nav. E., Massachusetts Institute of Technology, Department of Mechanical Engineering, May, 2020Thesis: S.M. in Engineering and Management, Massachusetts Institute of Technology, System Design and Management Program, May, 2020
Cataloged from the official PDF of thesis.
Includes bibliographical references (pages 625-626).
Trends in power system simulation that demand computationally-intensive, physics-based models may impede the acquisition of useful results for applications like condition-based maintenance [1], electrical plant load analysis (EPLA) [2], and the scheduling and tasking of finite generation and distribution resources. A tool that can quickly evaluate many scenarios, as opposed to intense, high fidelity modeling of a single operating scenario, may best serve these applications. This thesis presents a behavioral simulator that can quickly emulate the operation of a relatively large collection of electrical loads, providing "what-if" evaluations for more complete exploration of a design or plant operating envelope. Comparisons to field data collected from a microgrid on-board a 270 foot US Coast Guard "Famous" Class medium endurance cutter demonstrate the utility of this tool and approach. The usefulness of this tool is further demonstrated by showing simulated EPLA load factors within 10%of observed load factors over comparable mission sets, both inport and underway. Finally, this thesis will discuss the lessons learned during SPS development and testing, specifically, the need to expand its modeling capability so it can support direct current (DC) electrical distribution systems. The SPS, in its current form can only model alternating (AC) electrical distribution systems.
by Thomas Deeter.
Nav. E.
S.M. in Engineering and Management
Nav.E. Massachusetts Institute of Technology, Department of Mechanical Engineering
S.M.inEngineeringandManagement Massachusetts Institute of Technology, System Design and Management Program
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Abed, Nagy Youssef. "Physical dynamic simulation of shipboard power system components in a distributed computational environment." FIU Digital Commons, 2007. http://digitalcommons.fiu.edu/etd/1100.
Повний текст джерелаАнотація:
Shipboard power systems have different characteristics than the utility power systems. In the Shipboard power system it is crucial that the systems and equipment work at their peak performance levels.
One of the most demanding aspects for simulations of the Shipboard Power Systems is to connect the device under test to a real-time simulated dynamic equivalent and in an environment with actual hardware in the Loop (HIL). The real time simulations can be achieved by using multi-distributed modeling concept, in which the global system model is distributed over several processors through a communication link. The advantage of this approach is that it permits the gradual change from pure simulation to actual application.
In order to perform system studies in such an environment physical phase variable models of different components of the shipboard power system were developed using operational parameters obtained from finite element (FE) analysis.
These models were developed for two types of studies low and high frequency studies. Low frequency studies are used to examine the shipboard power systems behavior under load switching, and faults. High-frequency studies were used to predict abnormal conditions due to overvoltage, and components harmonic behavior. Different experiments were conducted to validate the developed models. The Simulation and experiment results show excellent agreement.
The shipboard power systems components behavior under internal faults was investigated using FE analysis. This developed technique is very curial in the Shipboard power systems faults detection due to the lack of comprehensive fault test databases.
A wavelet based methodology for feature extraction of the shipboard power systems current signals was developed for harmonic and fault diagnosis studies.
This modeling methodology can be utilized to evaluate and predicate the NPS components future behavior in the design stage which will reduce the development cycles, cut overall cost, prevent failures, and test each subsystem exhaustively before integrating it into the system.
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Zhai, Pei. "The hybrid real-time simulation system based on the electromechanical transient process simulation of power systems." Thesis, University of Macau, 2007. http://umaclib3.umac.mo/record=b1678026.
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Basher, Mohamed Abul. "Modeling, simulation and numerical analysis of transient characteristics of unregulated power system networks." Thesis, University of Ottawa (Canada), 2003. http://hdl.handle.net/10393/26441.
Повний текст джерелаАнотація:
Design and operations of electrical distribution-transmission networks are analyzed mathematically, implemented numerically and validated by simulation. A dynamic model of a three node network with capacitors, inductors, load current controllers and regulators is proposed and cast in a general model of differential state-space equations in canonical form. The model is implemented via a Runge-Kutta algorithm. Realistic values of distribution systems are chosen as input and validated interactively so as to avoid instabilities and maintain reasonable characteristics. Typically cases are analyzed and the behavior of state variable is represented graphically. The software used and mode of representation aim at providing a robust environment to help power managers in their daily control of load balancing. The analysis also opens directions for the design of power distribution network.
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Garcia-Valle, Rodrigo Joel. "Dynamic modelling and simulation of electric power systems using the Newton-Raphson method." Thesis, University of Glasgow, 2007. http://theses.gla.ac.uk/435/.
Повний текст джерелаАнотація:
The research work presented in this thesis is concerned with the development of a dynamic power flow computer algorithm using Newton's method. It addresses both the development of a positive sequence dynamic power flow algorithm for the dynamic study of balanced power systems and a fully-fledged three-phase dynamic power flow algorithm for the dynamic study of power systems exhibiting a significant degree of either structural or operational unbalance. As a prelude to the research work on dynamic power flows, a three-phase Newton-Raphson power flow algorithm in rectangular co-ordinates with conventional HVDC power plant modelling is presented in this thesis, emphasising the representation of converter control modes. The solution approach takes advantage of the strong numerical solutions for combined HVAC-HVDC systems, where power plant and operational imbalances are explicitly taken into account. The dynamic algorithm is particularly suited to carrying out long-term dynamic simulations and voltage stability assessments. Dynamic model representations of the power plants components and the load tap changing transformer are considered, and to widen the study range of dynamic voltage phenomena using this method, extensions have been made to include induction motor and polynomial load modelling features. Besides, reactive power compensators that base their modus operandi on the switching of power electronic valves, such as HVDC-VSC and the STATCOM are taken into account. The dynamic power flow algorithm has primarily been developed making use of the positive sequence and [dq] representations. Extensions are made to developing a three-phase power flows dynamic algorithm. Test cases for the various dynamic elements developed in this research are presented to show the versatility of the models and simulation tool, including a trip cascading event leading up to a wide-area voltage collaps. Comparisons with the output of a conventional transient stability program carried out where appropriate.
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Truong, Binh C. (Binh Chan) 1976. "Real-time system with non-real-time simulation for the power PC." Thesis, Massachusetts Institute of Technology, 2000. http://hdl.handle.net/1721.1/86571.
Повний текст джерелаАнотація:
Thesis (S.B. and M.Eng.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2000.Includes bibliographical references (leaf 47).
by Binh C. Truong.
S.B.and M.Eng.
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Svensson, Oskar. "Electrohydraulic Power Steering Simulation : Dynamic, thermal and hydraulic modelling." Thesis, KTH, Skolan för elektroteknik och datavetenskap (EECS), 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-265674.
Повний текст джерелаАнотація:
There are several benets of electrohydraulic power steering systems, as compared to hydraulicpower steering systems where the pump is driven directly by the engine of the vehicle. Someof these benets are increased eciency and improved steering performance. The purpose ofthis project is to create a simulation model of the electrohydraulic power steering system inSimulink, excluding the hydraulic circuit. The model should thus consist of the electric motor,the drive electronics, the control system, the hydraulic pump as well as the communication andinterface to the master simulation system in which the model will be used.As a start a mathematical model of the motor is derived. Then the motor controller includingtwo current controllers and a speed controller is developed. The switching signals for the threephase bridge that drives the motor are calculated using space vector modulation. The motordrives a hydraulic pump, which is modeled using data sheet eciency curves. Finally a thermalmodel of the drive is developed. To fulll real time requirements, a lumped parameter approachis chosen. The nal model is exported as a Functional Mock-up Unit, which is a black-boxencapsulation of the complete simulation model.The simulation model is compared to measurement data to conrm its validity. Thesecomparisons shows that the dynamic response of the motor and its controller are close to themeasured values and that the thermal model adequately corresponds to the thermal tests. Thehydraulic pump model varied from measurements more than the other sub-modules. It was,however, seen as acceptable. Overall the system response was satisfactory, but naturally a lotof future improvements and new features could be made to improve the model.Det finns flera fördelar med elektrohydraulisk servostyrning, där hydraulpumpen drivs av en el-motor, jämfört med hydraulisk servostyrning, där pumpen drivs direkt av fordonets förbränningsmotor. Några av dessa fördelar är ökad effektivitet och förbättrad styrprestanda. Syftet med detta projekt är att skapa en Simulink-modell av ett elektrohydraulisk system för servostyrning, exklusive hydraulkretsen. Modellen ska alltså bestå av delmodeller för elmotorn, drivelektroniken, styrsystemet, hydraulpumpen samt kommunikation med den övergripande simuleringsplattformen.Inledningsvis beskrivs en matematisk modell av elmotorn och efter det utvecklas motorstyrningen, bestående av två strömregulatorer samt en hastighetsregulator. Spänningen från strömregulatorerna uppnås genom space vector-modulation, som beräknar de pulskvoter som krävs för att uppnå denna spänning. Elmotorn driver en pump. Denna pump modelleras med hjälp av data från pumpens datablad. Slutligen modelleras drivelektronikens termiska egenskaper med ett termiskt nätverk. Den slutliga modellen omsluts av en Functional Mock-up Unit somintegreras i den övergripande simuleringsplattformen.
25
Kim, Keung Koo. "Design and simulation of a digital control system for a multi-modular power plant." Thesis, Massachusetts Institute of Technology, 1992. http://hdl.handle.net/1721.1/12931.
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Oko, Eni. "Study of power plant, carbon capture and transport network through dynamic modelling and simulation." Thesis, University of Hull, 2015. http://hydra.hull.ac.uk/resources/hull:11315.
Повний текст джерелаАнотація:
The unfavourable role of CO₂ in stimulating climate change has generated concerns as CO₂ levels in the atmosphere continue to increase. As a result, it has been recommended that coal-fired power plants which are major CO₂ emitters should be operated with a carbon capture and storage (CCS) system to reduce CO₂ emission levels from the plant. Studies on CCS chain have been limited except a few high profile projects. Majority of previous studies focused on individual components of the CCS chain which are insufficient to understand how the components of the CCS chain interact dynamically during operation. In this thesis, model-based study of the CCS chain including coal-fired subcritical power plant, post-combustion CO₂ capture (PCC) and pipeline transport components is presented. The component models of the CCS chain are dynamic and were derived from first principles. A separate model involving only the drum-boiler of a typical coal-fired subcritical power plant was also developed using neural networks. The power plant model was validated at steady state conditions for different load levels (70-100%). Analysis with the power plant model show that load change by ramping cause less disturbance than step changes. Rate-based PCC model obtained from Lawal et al. (2010) was used in this thesis. The PCC model was subsequently simplified to reduce the CPU time requirement. The CPU time was reduced by about 60% after simplification and the predictions compared to the detailed model had less than 5% relative difference. The results show that the numerous non-linear algebraic equations and external property calls in the detailed model are the reason for the high CPU time requirement of the detailed PCC model. The pipeline model is distributed and includes elevation profile and heat transfer with the environment. The pipeline model was used to assess the planned Yorkshire and Humber CO₂ pipeline network. Analysis with the CCS chain model indicates that actual changes in CO₂ flowrate entering the pipeline transport system in response to small load changes (about 10%) is very small (<5%). It is therefore concluded that small changes in load will have minimal impact on the transport component of the CCS chain when the capture plant is PCC.
27
Pundhir, Varun. "Designing and Simulation of Various Class-F Radio-Frequency Power Amplifier." Wright State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=wright1464363065.
Повний текст джерела
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Angeles-Camacho, Cesar. "Phase domain modelling and simulation of large-scale power systems with VSC-based FACTS equipment." Thesis, University of Glasgow, 2005. http://theses.gla.ac.uk/849/.
Повний текст джерелаАнотація:
Most of the analysis techniques available for planning and operation of multiphase power systems are based upon the assumption that the network operates under perfectly balanced conditions. The advantage of this assumption from the modelling view point is that only one phase of the three phase system needs to be considered for analysis, resulting in a reduced size of the problem at hand. However, the phase frame of reference offers a more general representation for the solution of power system problems than the frame of reference provided by the sequences. The former can accommodate networks containing any degree of unbalance whilst the latter is only applicable to power networks exhibiting perfect or near-perfect impedance balance between phases. The thesis reports on the development of steady state and time domain models of Flexible AC Transmission System (FACTS) controllers in the natural framework of electric systems, i.e. namely the phase co-ordinates domain. The FACTS equipment selected for analytical development in this research are: the static synchronous compensator (STATCOM), the static synchronous series compensator (SSSC), the unified power flow controller (UPFC) and the high-voltage direct current (HVDC). These power electronics-based controllers have the voltage source converter as their main constituent. The combined solution of both steady state and dynamic power flow equations pertaining to the VSC-based FACTS controllers and the power network are fully described in the thesis. The steady-state mathematical models of VSC-based FACTS controllers are formulated in nodal form using the frame of reference of the phases. Guidelines for their implementation into two distinct power flows algorithm namely, the Newton-Raphson in polar co-ordinates and the Newton-Raphson in rectangular coordinates are given. For the purpose of long-term dynamic assessment, a simultaneous solution using implicit trapezoidal integration method with Newton iteration is used to solve the set of differential-algebraic equations of generating plants and network components. In order to assess both the steady state and the dynamic behaviour of the models developed, a comprehensive, newly developed integrated software environment is used.
29
Zhang, Yuhao Ph D. Massachusetts Institute of Technology. "Simulation and fabrication of GaN-based vertical and lateral normally-off power transistors." Thesis, Massachusetts Institute of Technology, 2013. http://hdl.handle.net/1721.1/82179.
Повний текст джерелаАнотація:
Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2013.This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections.
Cataloged from student-submitted PDF version of thesis.
Includes bibliographical references (p. 92-98).
This thesis is divided in two parts. First, self-consistent electro-thermal simulations have been performed for single finger and multi-finger GaN-based vertical and lateral power transistors and were validated with experimental DC characteristics. The models were used to study the thermal performance of GaN-based vertical metal oxide semiconductor field-effect transistors (MOSFETs) and the lateral high electron mobility transistors (HEMTs) designed for different breakdown voltage application and at different size scaling levels. The comparison between two structures revealed that the vertical MOSFETs have the potential to achieve an up to 50% higher thermal performance, especially for higher breakdown voltage and higher size scaling level designs. Second, normally-off lateral MOS-HEMTs were developed by the combination of fluorine plasma treatment and high-temperature gate oxide deposition. Record performances have been achieved for the fluorinated MOS-HEMTs with a threshold voltage >3.5 V, a low on-resistance ~ 2 m[Omega]·cm2, a small threshold voltage hysteresis ~0.15 V, high enhancement-mode channel mobility ~ 1000 cm2V-1s-1, a breakdown voltage ~ 780 V, no current collapse and a stability with 24 h continuous on-state operation at 250 oC. In addition, an analytical model for the threshold voltage of fluorinated MOS-HEMTs was established for the first time, to enable accurate design and engineering of the threshold voltage for MOS-HEMTs. This novel technology has been demonstrated as promising to fabricate high-performance normally-off MOS-HEMTs.
by Yuhao Zhang.
S.M.
30
Kleinberg, Michael R. Miu Karen Nan. "Distributed multi-phase distribution power flow : modeling, solution algorithm, and simulation results /." Philadelphia, Pa. : Drexel University, 2007. http://hdl.handle.net/1860/1307.
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31
Wu, Yin. "Power Distribution System Modeling and Simulation of an Alternative Energy Testbed Vehicle." Ohio University / OhioLINK, 2010. http://rave.ohiolink.edu/etdc/view?acc_num=ohiou1289960977.
Повний текст джерела
32
Li, Dingyi. "Real-time simulation of shipboard power system and energy storage device management." Thesis, Kansas State University, 2014. http://hdl.handle.net/2097/17857.
Повний текст джерелаАнотація:
Master of ScienceDepartment of Electrical and Computer Engineering
Noel Schulz
Many situations can cause a fault on a shipboard power system, especially in naval battleships. Batteries and ultra-capacitors are simulated to be backup energy storage devices (ESDs) to power the shipboard power system when an outage or damage occurs. Because ESDs have advantages such as guaranteed load leveling, good transient operation, and energy recovery during braking operation, they are commonly used for electrical ship applications. To fulfill these requirements, an energy management subsystem (EMS) with a specific control algorithm must connect ESDs to the dc link of the motor drive system. In this research, the real-time simulation of shipboard power system (SPS), bidirectional DC-DC converter, EMS, and ESDs are designed, implemented, and controlled on OPAL-RT system to test SPS survivability and ESD performance in various speed operations.
33
Woodburn, David. "Modeling and Simulation of All-electric Aircraft Power Generation and Actuation." Doctoral diss., University of Central Florida, 2013. http://digital.library.ucf.edu/cdm/ref/collection/ETD/id/6037.
Повний текст джерелаАнотація:
Modern aircraft, military and commercial, rely extensively on hydraulic systems. However, there is great interest in the avionics community to replace hydraulic systems with electric systems. There are physical challenges to replacing hydraulic actuators with electromechanical actuators (EMAs), especially for flight control surface actuation. These include dynamic heat generation and power management.
Simulation is seen as a powerful tool in making the transition to all-electric aircraft by predicting the dynamic heat generated and the power flow in the EMA. Chapter 2 of this dissertation describes the nonlinear, lumped-element, integrated modeling of a permanent magnet (PM) motor used in an EMA. This model is capable of representing transient dynamics of an EMA, mechanically, electrically, and thermally.
Inductance is a primary parameter that links the electrical and mechanical domains and, therefore, is of critical importance to the modeling of the whole EMA. In the dynamic mode of operation of an EMA, the inductances are quite nonlinear. Chapter 3 details the careful analysis of the inductances from finite element software and the mathematical modeling of these inductances for use in the overall EMA model.
Chapter 4 covers the design and verification of a nonlinear, transient simulation model of a two-step synchronous generator with three-phase rectifiers. Simulation results are shown.Ph.D.
Doctorate
Electrical Engineering and Computer Science
Engineering and Computer Science
Electrical Engineering
34
Aguilera, Miguel. "Semantic and Physical Modeling and Simulation of Multi-Domain Energy Systems: Gas Turbines and Electrical Power Networks." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-214532.
Повний текст джерелаАнотація:
The ITEA3 OpenCPS (Open Cyber-Physical System Model-Driven CertifiedDevelopment) project focuses on interoperability between the Modelica/UnifiedModeling Language (UML)/Functional Mock-up Interface (FMI) standards, improved(co-)simulation execution speed, and verified code generation. The project aims to developa modeling and simulation framework for cyber-physical and multi-domain systems. Oneof the main use cases for the framework, is the multi-domain equation-based modelingand simulation of detailed gas turbine power plants (including the explicit equation-basedmodeling of turbomachinery dynamics) and the electrical power grid.In this work, UML class diagrams based on the Common Information Model (CIM)standard are used to describe the semantics of the electrical power grid. An extension basedon the standard ISO 15926 has been proposed to derive the multi-domain semanticsrequired by the models that integrate the electrical power grid with the detailed gas turbinedynamics.Furthermore, the multi-domain physical modeling and simulation Modelica language hasbeen employed to create the equation-based models of the use case of this project. Acomparative analysis between the Single-Domain and Multi-Domain model responses hasbeen performed both in time and frequency. The results show some interesting differencesbetween the turbine dynamics representation of the commonly used GGOV1 standardmodel and the less simplified model of a gas turbine.Finally, the models from each domain can be exchanged between two differentstakeholders by means of Functional Mock-Up Units (FMUs), defined by the FMIstandard. Promising test results were obtained with different simulation tools that supportthe standard, which demonstrates the feasibility of exchanging unambiguous multi-domainmodels with a detailed gas turbine representation. This shows the potential of the FMIstandard for manufacturers to exchange equation-based multi-domain models, while at thesame time protecting their intellectual property.Projektet ITEA3 OpenCPS (Öppen, certifierad modelldriven utveckling för cyberfysiskasystem) fokuserar på interoperabilitet mellan standarderna för Modelica, Unified ModelingLanguage (UML) och Functional Mock-up Interface (FMI), förbättring av tidsåtgångenför (sam-)simulering, samt verifierad kodgenerering. Projektet syftar till att utveckla enplattform för modellering och simulering av cyberfysiska system och system somrepresenteras av olika sorters fysikaliska modeller (eng. multi-domain modeling). Ett av defrämsta användningsområdena för plattformen är ekvationsbaserad modellering ochsimulering av detaljerade gasturbinmodeller i elkraftverk (inklusive explicitekvationsbaserad modellering av dynamiken mellan termiska och roterande komponenter)som är sammankopplade med kraftsystemet.I detta examenarbete används klassdiagram i UML baserade på standarden för CommonInformation Model (CIM) och komponentdiagram från SysML för att beskrivakraftsystemet. En utvidgning baserat på ISO 15926-standarden föreslås för att härledasemantiken för modeller som integrerar både kraftsystemet och detaljerad dynamik förgasturbiner.Vidare så har Modelica, ett språk för modellering och simulering av olikartade fysikaliskasystem, utnyttjats för att skapa ekvationsbaserade modeller som utvecklats i detta projekt.En komparativ analys har genomförts för en detaljerad modell med termodynamik och enförenklad modell genom undersökning av både frekvenssvar och tidssimuleringar.Resultaten visar att skillnader uppstår mellan den detaljerade modellen och den ikraftsystemsammanhang allmänt använda modellen GGOV1, vilket kan förklaras medförenklingar i den snareSlutligen kan modeller från olika fysikaliska domäner utbytas mellan intressenter med s.k.Functional Mock-Up Units (FMU-enheter), som definieras av FMI-standarden. Lovanderesultat uppnåddes med simuleringsverktyg som stöder FMI-standarden vilket visarmöjligheten till ett otvetydigt utbyte av detaljerade gasturbinmodeller och elkraftsmodeller.Detta visar potentialen i FMI-standarden för modellutbyte mellan olikamodelleringsdomäner, vilket skulle kunna låta tillverkare att dela ekvationsbaserademodeller utan att ge upp immateriella tillgångar.
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Spruce, Christopher John. "Simulation and control of windfarms." Thesis, University of Oxford, 1993. http://ora.ox.ac.uk/objects/uuid:24f51a31-e2f9-422f-9837-3c28cfe12ccc.
Повний текст джерелаАнотація:
This thesis examines the design of supervisory controllers for windfarms of pitch-controlled wind turbines. The control objectives are the maximisation of the financial income from the generated electricity and the minimisation of the turbines' fatigue damage. The design exploits the wide variations in the ratio of financial income to fatigue damage which are found both spatially across windfarms and as a function of time. The supervisory control strategy makes use of the ability of pitch-controlled turbines to operate with variable power set points; a capability which is rarely exploited in practice. A windfarm simulation which has been developed for the purposes of testing supervisory controllers is described. It is shown that the simulation is a suitable test-bed for this application. Results are presented which demonstrate how the fatigue damage of a turbine's gearbox and structural components vary as functions of the mean wind-speed, turbulence intensity and power set point, both for isolated turbines and for turbines experiencing wake effects. A lifetime performance function is proposed and 'ideal' power set point curves are evaluated using a genetic search algorithm. It is shown that significant improvements in performance can be achieved if the operation of the turbines is altered to take account of variable electricity tariffs. A windfarm control strategy that splits the turbines into interacting and non-interacting categories is found to give good results. Using data generated by the simulation, it is shown that simple cost functions can be developed for non-interacting turbines which, when used in a controller, give performance that is close to the 'ideal'. A similar cost function is applied to a group of three interacting turbines, and it is found that substantial reductions in all measures of total annual fatigue damage are achieved for a small reduction in total annual financial income. The on-line implementation of windfarm supervisory controllers is discussed and the behaviour of a simple hill-climbing algorithm is examined using a simulated group of three interacting turbines.
36
Zhao, Jiayun. "A Simulation-based Decision Support System for Electric Power Demand Management Considering Social Network Interactions." Diss., The University of Arizona, 2013. http://hdl.handle.net/10150/311558.
Повний текст джерелаАнотація:
A two-level agent-based modeling framework is proposed for the electric power system to solve the problems of renewable energy utilization and demand-side management. While in the detailed level of the framework the customers and utility companies are modeled as agents to represent electricity demand and supply performances, respectively, the high level reflects the aggregated performance of the considered electricity market via state space models. To connect the two levels, a social network is introduced as a dynamic medium for the interactions among customer agents. While the customers' consumption behaviors are modeled at lower level and affected by each other, their individual performances contribute to the system performance in the high level. This dissertation concerns three problems. First, the problem of renewable energy adoption concerns penetration process of distributed solar systems with various incentive policies (i.e., Income Tax Credits and Feed-in Tariff) for renewable energy. The proposed hybrid model incorporates agent-based modeling and system dynamics to simulate the solar system diffusion process among the residential customers. Second, the demand-side management problem focuses on scheduling the Plug-in Hybrid Electric Vehicles (PHEV) charging under different scenarios of demand response programs (i.e., Time-of Use and Real-time Pricing). For the Time-of Use (TOU) program, the decision-support analysis results from simulation-based optimization for both customers and the utility company. For the Real-time Pricing (RTP) program, the discussion is to find proper pricing functions according to different customers. Third, the problem concerns the agent interaction based on different architectures of social network (i.e., small-world and scale-free) and the network evolution based on triadic closure. Such interaction is applied to the first two problems with the effect of changing the customers' social connections, preferences in consumption behaviors and acceptable grid prices. Furthermore, to extend the demand-side management problem, this research also discusses the energy management at individual households integrating PV generation system, battery storage and electric vehicle under demand response programs. The conceptual model is based on the threshold method to suggest residential customers when to use the electricity from which sources (PV generation, storage, or local grid).
37
Gil-García, Álvaro Antonio. "Thermodynamic behaviour of supercritical water as working fluid in advanced coal-fired power plants : simulation and design study." Thesis, University of Birmingham, 2017. http://etheses.bham.ac.uk//id/eprint/7734/.
Повний текст джерелаАнотація:
The UK is facing an energy crisis due to the closure of old nuclear power plants which will not be replaced until Generation III nuclear reactors are built. Coal is a realistic option to fill the gap, although there is a need to use cleaner and efficient technologies as a means to comply with global environmental regulations. Supercritical coal-fired power is a viable clean coal technology; however the UK National Grid Code is built around conventional power plants, and thus compliance is uncertain. Modelling the thermal behaviour of the supercritical boiler water cycle using computational fluid dynamics is a practical method to approach compliance. The CFD models developed with the software Comsol Multiphysics were validated and verified using experimental and numerical data, respectively. Subsequently, a test-element representing one pipe from the water wall was scaled-down to match computational requirements, and tested at two different thermal boundary conditions. A strong, forcedconvective flow was revealed, with buoyancy effects at the inlet and a considerable influence of thermal acceleration. The sharp changes of the thermo-physical properties were the most influential hydrothermal factor. Heat transfer coefficient peaked near the pipe inlet, and the outlet section showed mild hydro-thermal performance, impaired by the acceleration effects.
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Baradar, Mohamadreza. "On the Efficiency and Accuracy of Simulation Methods for Optimal Power System Operation : Convex Optimization Models for Power System Analysis, Optimal Utilization of VSC-type DC Wind Farm Grids and FACTS Devices." Doctoral thesis, KTH, Elektriska energisystem, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-166383.
Повний текст джерелаАнотація:
Recently, significant changes in electric power systems such as rapid developmentof smart grid and electricity market and integration of non-dispatchablesources have added more complexity to the Power Flow Scheduling (PFS) andPower Balancing (PB) models. For instance, non-dispatchable sources introducean increasing level of uncertainty in the electricity market and power system operation.One of the solutions for handling these uncertainties in the power systemoperation is the improvement of system flexibility through a more efficient operationof power systems. On the other hand, efficient operation can be achieved bywell capturing variable behavior of uncertain sources such as wind power sourceswhich in turn demands efficient and robust PFS/PB models. This way, a moreflexible system, capable of efficiently accommodating higher levels of wind powerchanges, can be achieved. All these factors increase a need for PFS/PB models suchas Power Flow (PF) and Optimal Power Flow (OPF) models which can addressthese new challenges in an efficient, reliable, and economic way while supportingthe power system operation and control. In this regard, various solution methodshave been developed for solving different forms of PF/OPF formulation. The difficultyof solving OPF problems increases significantly with increasing network sizeand complexity. One of these complexities is how to model advanced controllable devices such as HVDC grids and Flexible AC Transmission Systems (FACTS) devices.Accurate handling of these complexities has limited the use of OPF in manyreal-world applications mainly because of its associated computational challenges.The main reasons behind computational challenges are nonlinearity and especiallynon-convexity of constraints representing power system and its components. Inthis regard, OPF problems are classified into two main groups. In the first group,researchers adopt Nonlinear programming (NLP) approach to fully represent thenonlinearity of the power system for the sake of accuracy but with the cost of complexityin the model. Computational and theoretical challenges associated withNLP approaches are then used as a motivation towards developing a more simplifiedOPF model, leading to the second group of OPF models known as LinearProgramming (LP) based OPF models. LP approaches are fast, reliable, and especiallyconvex, and therefore guarantee a global optimum to the simplified OPFproblem. The problem of LP approach to OPF is that the LP solution of OPF may not even be a feasible solution of original nonlinear OPF at all. Another issueassociated with LP models is that complex power system devices such as HVDClinks are difficult to be incorporated. These limitations have restricted the applicationof LP approaches for many OPF problems. According to the mentionedadvantages and disadvantages of NLP and LP based OPF models, what we seeks isan OPF model which can have main advantages of both LP OPF models (Efficientnumerical solvers) and full AC OPF models (Results accuracy). In this thesis, wedevelop convex optimization problems which can be adopted as both PF and OPFmodels which are capable of catching the nonlinear nature of power systems asmuch as possible while can be solved by efficient solution methods such as InteriorPoint Methods (IPMs). These OPF models can incorporate HVDC links, windfarm Multi Terminal HVDC (MTDC) grids, and shunt FACTS devices.QC 20150521
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Wang, Yue. "Modelling and simulation study of IGCC power plant with activated carbon-based carbon capture process." Thesis, University of Warwick, 2016. http://wrap.warwick.ac.uk/79967/.
Повний текст джерелаАнотація:
Integrated Gasification Combined Cycle (IGCC) is considered as a viable option for low emission power generation and carbon-dioxide sequestration. Modelling development and simulation study is essential part for the process of IGCC design and development. This PhD project is aiming to conduct the modelling and simulation study of IGCC power plant by building sub-modules such as gasifier, water gas shift reactor, acid gas removal unit, gas turbine and HRSG, etc. and connecting these modules together for the whole process study. In addition, the impact for the integration of IGCC with activated carbons-based pressure swing adsorption carbon capture process is investigated by using a PSA model developed and validated by University of Birmingham. A simplified zero dimension gasification model is developed based on Texaco gasifier and validated by reference and industry data. The model development is based on mass balance, chemical equilibrium and energy balance. The prediction results for syngas contents concentrations are proved to be reasonably acceptable and the syngas contents changes with key input parameters changes are studied. The model is then used to generate a variable syngas stream to study the dynamic performance of the other sub-modules. A one dimension dynamic model based on Shell slagging gasifier is developed. The model can successfully show the characteristics of slag layers formation and the syngas stream change with response to input parameters change. By using step rise of oxygen input and steam blast input, the dynamic performance of syngas temperature, syngas contents, slag mass flow rate and slag layers thickness is analysed and compared. It is found that oxygen input show relative larger impact on gasifier operation than steam blast for the studied working conditions. Auxiliary modules in a gasification enabled plant and combined cycle power plant are modelled with Thermolib Software. Basic principles of this software are introduced. Simplified quench process, WGS with heat recovery, acid gas removal unit, gas turbine, HRSG and electrical generator are modelled by using the blocks from Thermolib. The simulation results show the dynamic changes of key output variables such as power output, syngas temperature and contents concentrations. PSA model developed by UoB based on ACs is introduced and a 9 step 8 beds cycle model is used for the integration with IGCC model. This PSA model can achieve 80.89% CO2 capture rate with 87.33% of N2 recovery rate without any additional equipment. N2 is used to represent H2 for the simulation. Four cases for IGCC integrated with carbon capture are studied for the energy penalty analysis. It is predicted that the efficiency loss for IGCC power plant with 80.89% carbon capture will be 10.96%. The limitations of using N2 to represent H2 for the PSA model are discussed and it is predicted the real efficiency loss will be lower than the simulation results.
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Ghodrati, Ashkan, and Ahmed Rashid. "Modelling and Simulation of a Power Take-off in Connection with Multiple Wave Energy Converters." Thesis, Blekinge Tekniska Högskola, Institutionen för tillämpad signalbehandling, 2014. http://urn.kb.se/resolve?urn=urn:nbn:se:bth-3396.
Повний текст джерелаАнотація:
The objective of this thesis is to develop a model that will integrate multiple buoys to a power take-off hub. The model will be derived using a time domain analysis and will consider the hydraulic coupling of the buoys and the power take-off. The derived model is reproduced in MATLAB in order to run simulations. This will give possibility to conduct a parameter study and evaluate the performance of the system. The buoy simulation model is provided by Wave4Power (W4P). It consists of a floater that is rigidly connected to a fully submerged vertical (acceleration) tube open at both ends. The tube contains a piston whose motion relative to the floater-tube system drives a power take-off mechanism. The power take-off model is provided by Ocean Harvesting Technologies AB (OHT). It comprises a mechanical gearbox and a gravity accumulator. The system is utilized to transform the irregular wave energy into a smooth electrical power output. OHT's simulation model needs to be extended with a hydraulic motor at the input shaft. There are control features in both systems, that need to be connected and synchronized with each other. Another major goal within the thesis is to test different online control techniques. A simple control strategy to optimize power capture is called sea-state tuning and it can be achieved by using a mechanical gearbox with several discrete gear ratios or with a variable displacement pump. The gear ratio of the gear box can be regulated according to a 2D look up table based on the average wave amplitude and frequency over a defined time frame. The OHT power take-off utilizes a control strategy, called spill function, to limit the excess power capture and keep the weight accumulator within a span by disengaging the input shaft from the power take-off. This is to be modified to implement power limitation with regulation of the gear ratio of the gearbox.+46736290781
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Terrier, Viktor. "North European Power Systems Reliability." Thesis, KTH, Elkraftteknik, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-202581.
Повний текст джерелаАнотація:
The North European power system (Sweden, Finland, Norway, Denmark, Estonia, Latvia and Lithuania) is facing changes in its electricity production. The increasing share of intermittent power sources, such as wind power, makes the production less predictable. The decommissioning of large plants, for environmental or market reasons, leads to a decrease of production capacity while the demand can increase, which is detrimental to the power system reliability. Investments in interconnections and new power plants can be made to strengthen the system. Evaluating the reliability becomes essential to determine the investments that have to be made. For this purpose, a model of the power system is built. The power system is divided into areas, where the demand, interconnections between areas, and intermittent generation are represented by Cumulative Distribution Functions (CDF); while conventional generation plants follow a two-state behaviour. Imports from outside the system are set equal to their installed capacity, with considering that the neighbouring countries can always provide enough power. The model is set up by using only publicly available data. The model is used for generating numerous possible states of the system in a Monte Carlo simulation, to estimate two reliability indices: the risk (LOLP) and the size (EPNS) of a power deficit. As a power deficit is a rare event, an excessively large number of samples is required to estimate the reliability of the system with a sufficient confidence level. Hence, a pre-simulation, called importance sampling, is run beforehand in order to improve the efficiency of the simulation. Four simulations are run on the colder months (January, February, March, November, December) to test the reliability of the current system (2015) and of three future scenarios (2020, 2025 and 2030). The tests point out that the current weakest areas (Finland and Southern Sweden) are also the ones that will face nuclear decommissioning in years to come, and highlight that the investments in interconnections and wind power considered in the scenarios are not sufficient to maintain the current reliability levels. If today’s reliability levels are considered necessary, then possible solutions include more flexible demand, higher production and/or more interconnections.Det nordeuropeiska elsystemet (Sverige, Finland, Norge, Danmark, Estland, Lettland och Litauen) står inför förändringar i sin elproduktion. Den ökande andelen intermittenta kraftkällor, såsom vindkraft, gör produktionen mindre förutsägbar. Avvecklingen av stora anläggningar, av miljö- eller marknadsskäl, leder till en minskning av produktionskapaciteten, medan efterfrågan kan öka, vilket är till nackdel för kraftsystemets tillförlitlighet. Investeringar i sammankopplingar och i nya kraftverk kan göras för att stärka systemet. Utvärdering av tillförlitligheten blir nödvändigt för att bestämma vilka investeringar som behövs. För detta ändamål byggs en modell av kraftsystemet. Kraftsystemet är uppdelat i områden, där efterfrågan, sammankopplingar mellan områden, och intermittent produktion representeras av fördelningsfunktioner; medan konventionella kraftverk antas ha ett två-tillståndsbeteende. Import från länder utanför systemet antas lika med deras installerade kapaciteter, med tanke på att grannländerna alltid kan ge tillräckligt med ström. Modellen bygger på allmänt tillgängliga uppgifter. Modellen används för att generera ett stort antal möjliga tillstånd av systemet i en Monte Carlo-simulering för att uppskatta två tillförlitlighetsindex: risken (LOLP) och storleken (EPNS) av en effektbrist. Eftersom effektbrist är en sällsynt händelse, krävs ett mycket stort antal tester av olika tillstånd i systemet för att uppskatta tillförlitligheten med en tillräcklig konfidensnivå. Därför utnyttjas en för-simulering, kallad ”Importance Sampling”, vilken körs i förväg i syfte att förbättra effektiviteten i simuleringen. Fyra simuleringar körs för de kallare månaderna (januari, februari, mars, november, december) för att testa tillförlitligheten i nuvarande systemet (2015) samt för tre framtidsscenarier (2020, 2025 och 2030). Testerna visar att de nuvarande svagaste områdena (Finland och södra Sverige) också är de som kommer att ställas inför en kärnkraftsavveckling under de kommande åren. De indikerar även att planerade investeringar i sammankopplingar och vindkraft i scenarierna inte är tillräckliga för att bibehålla de nuvarande tillförlitlighetsnivåerna. Om dagens tillförlitlighetsnivåer antas nödvändiga, så inkluderar möjliga lösningar mer flexibel efterfrågan, ökad produktion och/eller fler sammankopplingar.
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Mousavi, Takami Kourosh. "Process Control and Simulation of Ferromagnetic Strip in the Power Transformers and Electrical Machines Applications : Electric power systems." Doctoral thesis, Västerås : School of Sustainable Development of Sociaty and Technology, Mälardalen University, 2009. http://urn.kb.se/resolve?urn=urn:nbn:se:mdh:diva-6648.
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Conradie, Antonie Eduard. "Performance optimization of engineering systems with particular reference to dry-cooled power plants." Thesis, Link to the online version, 1995. http://hdl.handle.net/10019.1/1326.
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Niknam, Nastaran. "H-Bridge Converter Modeling and Simulations for a Battery Power Management System." Youngstown State University / OhioLINK, 2016. http://rave.ohiolink.edu/etdc/view?acc_num=ysu1470415647.
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Eriksson, Peter. "Milling accuracy improvement of a 6-axis industrial robot through dynamic analysis : From datasheet to improvement suggestions." Thesis, KTH, MWL Marcus Wallenberg Laboratoriet, 2019. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-250244.
Повний текст джерелаАнотація:
The industrial robot is a flexible and cheap standard component that can becombined with a milling head to complete low accuracy milling tasks. Thefuture goal for researchers and industry is to increase the milling accuracy, suchthat it can be introduced to more high value added operations.The serial build up of an industrial robot bring non-linear compliance andchallenges in vibration mitigation due to the member and reducer design. WithAdditive Manufacturing (AM), the traditional cast aluminum structure couldbe revised and, therefore, milling accuracy gain could be made possible due tostructural changes.This thesis proposes the structural changes that would improve the millingaccuracy for a specific trajectory. To quantify the improvement, first the robothad to be reverse engineered and a kinematic simulation model be built. Nextthe kinematic simulation process was automated such that multiple input parameterscould be varied and a screening conducted that proposed the mostprofitable change.It was found that a mass decrease in any member did not affect the millingaccuracy and a stiffness increase in the member of the second axis would increasethe milling accuracy the most, without changing the design concept. To changethe reducer in axis 1 would reduce the mean position error by 7.5 % and themean rotation error by 4.5 % approximately, but also reduces the maximumspeed of the robot. The best structural change would be to introduce twosupport bearings for axis two and three, which decreased the mean positioningerror and rotation error by approximately 8 % and 13 % respectively.En industrirobot är en anpassningsbar och relativt billig standardkomponent.Den kan utrustas med ett fräshuvud för att genomföra fräsoperationer med låg noggrannhet. Det framtida målet för forskare och industri är att öka noggrannheten vid fräsning så att dess användningsområde kan utökas till ändamål som kräver högre precision.Den seriella uppbyggnaden av en industrirobot medför icke-linjär styvhet och därmed utmaningar vid vibrationsdämpning. Detta på grund av den strukturella uppbyggnaden då en industrirobot kan förenklat sägas vara uppbyggd av balkelement som i ledpunkterna kopplas samman av växellådor. Med friformsframställning kan en mer komplex struktur erhållas jämfört med traditionellt gjuten aluminiumkonstruktion därmed skulle en ökad noggrannhet vid fräsning kunna uppnås.Det här examensarbetet föreslår strukturella ändringar som skulle kunna öka noggrannheten vid fräsning för en specifik fräsbana. För att kvantifiera förbättringen, var det först nödvändigt att utgående från tillgänglig data konstruktion en specific robot samt att bygga en kinematisk modell. Därefter automatiserades beräkningsflödet så att ett flertal indata kunde varieras. Detta resulterande i en kombinationsstudie som visade den mest gynsamma strukturella förändringen.Det visade sig att en minskning av balkelementens massa inte påverkade nogrannheten. Att öka styvheten i balkelementet från den andra axeln skulle d¨aremot öka nogrannheten mest utan att behöva ändra robotens uppbyggnad.Att byta växellåda i första axeln kan öka positionsnogrannheten med nära 7.5 % och rotationsnoggrannheten med cirka 4.5 % men ändringen sänker samtidigt den maximala hastigheten. Den bästa strukturella förändringen vore att introducera ett stödlager vid axel två respektive tre, vilket skulle förbättra positionsnogrannheten med cirka 8 % och rotationsnogrannheten med nära 13 %.
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Vichis-Rodriguez, Damian Sergio. "Modelling of three phase AC machines suitable for internal fault simulation, detection and analysis in multi-machine power systems." Thesis, University of Glasgow, 2010. http://theses.gla.ac.uk/1782/.
Повний текст джерелаАнотація:
The ever increasing demand for electrical energy has meant that electrical power systems have evolved to be the highly complex networks that are in existence today, where the transient interactions that take place between large synchronous generators have been the focus of advanced research for many decades. More recently, the proliferation of synchronous and asynchronous generators of comparatively small rating, which are not centrally planned, has added new impetus to this area of research. At a time when not only technical but also economic and environmental concerns must be carefully assessed, more realistic models of the individual power plant transient response and its interaction with the rest of the network become mandatory to achieve more accurate analysis of the network operation and prevent wastage of technical and economical resources. The main thrust of this research project is to develop comprehensive models of rotating machinery with which to assess the transient response of electrical power networks that undergo severe unbalanced operation due to faulty conditions developing anywhere in the power network, including the rotating machinery’s windings. To achieve an unrivalled speed of response, a nodal-based model of the electrical power network has been developed, enabling the study of power networks of any size and topological formation with the utmost flexibility and efficiency. The rotating machinery addressed in this research work is the three-phase synchronous generator and the three-phase asynchronous (induction) machine. In multi-machine power systems transient studies, it is common to look at all the rotating machinery in the network as being healthy units having an idealized sinusoidally distributed stator winding – the possibility of a severe unbalanced condition internal to the machine due to internal fault or the effect of space harmonics, has, so far, not been addressed in a multi-machine environment. In this research work, new EMTP type models, with enhanced numerical properties, are constructed for the simulation of internal and external machine fault phenomena with different levels of details including the effects of saturation and space harmonics. Advanced numerical methods are employed to improve on the numerical stability of the network model allowing the use of larger time steps than what otherwise is possible with traditional numerical methods, enabling the new model to execute faster than existing models and yet to exhibit the same degree of numerical accuracy with an unrivalled degree of modelling flexibility. A case in point is an application made to model the transient response of a Variable Frequency Transformer (VFT) undergoing internal faults on its stator side. The rotating machinery models with internal fault representation developed in this research lend themselves to an application in the area of condition monitoring, where a new method is developed to detect internal faults in the stator side of three phase rotating machinery. The method is shown to be highly effective when applied to machines operating in an isolated environment as well as in a multi-machine power system, performing very well when applied to different types of equipment and various kinds of internal faults.
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Zhu, Kunpeng. "Large Eddy Simulation and LIDAR 3-D Mapping for Optimization of Wind Power Generation in Limited-space Applications." The Ohio State University, 2011. http://rave.ohiolink.edu/etdc/view?acc_num=osu1314907225.
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Mahmud, Sadab. "Development and Simulation of Maximum Power Point Tracking (MPPT) Controller with Ripple Correlation Control (RCC) for Deep Space Spacecraft." University of Toledo / OhioLINK, 2020. http://rave.ohiolink.edu/etdc/view?acc_num=toledo1588686169167826.
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Luo, Xiaobo. "Process modelling, simulation and optimisation of natural gas combined cycle power plant integrated with carbon capture, compression and transport." Thesis, University of Hull, 2016. http://hydra.hull.ac.uk/resources/hull:14005.
Повний текст джерелаАнотація:
Reducing CO₂ emissions from fossil fuel-fired power plants is a significant challenge, technically and economically. Post-combustion carbon capture (PCC) using amine solvents is widely regarded as the most promising technology that can be commercially deployed for carbon capture from fossil fuel-fired power plants. However, for its application at full commercial scale, the main barrier is high cost increment of the electricity due to high capital costs and significant energy penalty. This thesis presents the studies on optimal design and operation of Monoethanolamine (MEA)-based PCC process and the integrated system with natural gas combined cycle (NGCC) power plant through modelling, simulation and optimisation, with the aim to reduce the cost of PCC commercial deployment for NGCC power plants. The accuracy of optimisation depends on good predictions of both process model and economic model. For the process modelling, the philosophy with its framework was analysed for this reactive absorption (RA) process. Then the model was developed and validated at three stages. In the first stage, the predictions of thermodynamic modelling were compared with experimental data of CO₂ solubility in aqueous MEA solutions. The results show the combination of correlations used in this study has higher accuracy than other three key published contributions. Then key physical properties of MEA-H₂O-CO₂ system were also validated with experimental data from different publications. Lastly, a steady state process model was developed in Aspen Plus® with rate-based mass transfer and kinetic-controlled reactions. The process model was validated against comprehensive pilot plant experiment data, in terms of absorption efficiency and thermal performance of the integrated system. The cost model was developed based on the major equipment costs provided by vendors after detailed engineering design in a benchmark report. The uncertainty of this method could be in the range of from −15% to 20%, instead of other empirical methods with uncertainty of from −30% to 50%. The cost model was integrated into the process model by coding Fortran subroutine in Aspen Plus®. Using this integrated model, the optimisation studies were carried out for the PCC process only. The impact of key variables variation was also analysed. Subsequently, the scope of this study was extended to cover different sections of the integrated system including a 453MWe NGCC power plant, PCC process, CO₂ compression trains and CO₂ transport pipeline network. For the integration of NGCC power plant with PCC process and CO₂ compression, exhaust gas recirculation (EGR) technology was investigated and showed significant economic benefit. A specific supersonic shock wave compressor was adopted for the CO₂ compression and its heat integration options with power plant and PCC process were studied. For the study on the CO₂ transport pipeline network planned in the Humber region of the UK, a steady state process model was developed using Aspen HYSYS®. The process model was integrated with Aspen Process Economic Analyzer® (APEA), to carry out techno-economic evaluations for different options of the CO₂ compression trains and the trunk onshore\offshore pipelines respectively. The results show the optimal case has an annual saving of 22.7 M€ compared with the base case. In the end, optimal operations of NGCC power plant integrated with whole carbon capture and storage (CCS) chain under different market conditions were studied. Levelised cost of electricity (LCOE) is formulated as the objective function. The optimal operations were investigated for different carbon capture level under different carbon price, fuel price and CO₂ transport and storage (T&S) price. The results show that carbon price needs to be over €100/ton CO₂ to justify the total cost of carbon capture from the NGCC power plant and needs to be €120/ton CO₂ to drive carbon capture level at 90%. The results outline the economic profile of operating an NGCC power plant integrated with CCS chain. It could help power plants operators and relevant government organizations for decision makings on the commercial deployment of solvent-based PCC process for power plans.
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Chaillout, J. J. "De la simulation .... .... à la récupération." Habilitation à diriger des recherches, Université de Grenoble, 2007. http://tel.archives-ouvertes.fr/tel-00614924.
Повний текст джерелаАнотація:
Le " Chapitre II : De la simulation...." résume ma connaissance des principales méthodes numériques utilisées en électromagnétisme. Suit ensuite le résumé de mes études les plus représentatives dans le domaine de la simulation numérique en électromagnétisme : une en statique, une en quasi-statique avec couplage faible et une en propagation d'ondes. Souvent seule la méthode appliquée à des cas test est présentée, car leurs niveaux de confidentialité empêchent d'en présenter les résultats quantifiés. Le " Chapitre III :.... À la récuperation " contient tout d'abord un état de l'art de la récupération d'énergie permettant de comparer les performances des différents couples sources/conversion. Pour cela, j'insiste particulièrement sur tous les facteurs à prendre en compte pour choisir le couple optimal dans un environnement donné. Ensuite, on y trouve le résumé des deux thèses et d'un DRT que j'ai co-encadrés dans le domaine. Le " Chapitre IV : perspectives " présente les évolutions de ma carrière scientifique dans les deux axes développés dans ce rapport. Pour les évolutions souhaitables des méthodes numériques de manière générale et plus particulièrement dans mon Département, j'en expose ma vision et comment je prévois d'y contribuer. Pour l'axe énergétique, je présente les travaux prévus afin de conforter nos succès récents ainsi que les collaborations en cours ou amorcées.