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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
31

Technical and economical evaluation of combined cooling, heat and power technology: a brazilian study case considering different consumers

Givisiez, Arthur Gonçalves 29 August 2018 (has links)
Submitted by Geandra Rodrigues (geandrar@gmail.com) on 2018-09-25T13:55:05Z No. of bitstreams: 1 arthurgoncalvesgivisiez.pdf: 15097769 bytes, checksum: e434481fde7014f783d8b75137429fba (MD5) / Approved for entry into archive by Adriana Oliveira (adriana.oliveira@ufjf.edu.br) on 2018-10-01T18:11:02Z (GMT) No. of bitstreams: 1 arthurgoncalvesgivisiez.pdf: 15097769 bytes, checksum: e434481fde7014f783d8b75137429fba (MD5) / Made available in DSpace on 2018-10-01T18:11:02Z (GMT). No. of bitstreams: 1 arthurgoncalvesgivisiez.pdf: 15097769 bytes, checksum: e434481fde7014f783d8b75137429fba (MD5) Previous issue date: 2018-08-29 / O mundo está tentando mudar para um ambiente de energia mais limpa, especialmente no setor de geração de eletricidade, que é responsável por uma grande parcela das emissões de CO2. No Brasil, fontes renováveis são responsáveis por grande parte da geração de eletricidade, mas mudanças atuais no clima brasileiro trouxeram uma necessidade de diversificação na matriz energética. Logo, a geração distribuída é uma boa maneira de diversificar a matriz energética brasileira. Considerando que os sistemas de cogeração se enquadram na geração distribuída, e que os prédios brasileiros necessitam de resfriamento, devido ao clima quente, o uso de cogeração adicionado à um chiler de absorção ou absorção pode ser muito útil. O sistema de trigeração é um processo altamente eficiente, que pode produzir eletricidade, aquecimento e resfriamento a partir da mesma fonte de energia primária. No entanto, existem poucas pesquisas sobre os sistemas de trigeração no Brasil, especialmente em pequena e micro escala. Assim, esta dissertação fará uma avaliação técnica e econômica de sistemas de micro e trigeração para diferentes edifícios sob políticas tarifárias distintas no Brasil. Para tanto, este trabalho otimizará o dimensionamento e o cronograma de despacho mensal dos sistemas de trigeração para cada um dos quatro estudos de caso. Em seguida, avaliará o valor presente líquido máximo (VPL) considerando a variação da taxa de desconto e da taxa de conversão do dólar norte-americano. Na sequência, o índice de dependência da rede (GDI), o payback descontado, o custo nivelado da energia (LCOE) e a razão da energia primária (PER) para os melhores VPLs serão apresentados e analisados. Como resultado, esta dissertação mostrará que as plantas de trigeração podem ser lucrativas e certamente ser uma maneira eficiente de utilização de uma geração distribuída confiável e controlável. Além disso, provará que é possível encontrar situações em que a planta de trigeração possa oferecer uma alta taxa de energia primária (PER), um adequado custo de energia nivelado (LCOE) e, ao mesmo tempo, pode proporcionar economia financeira com tempo de retorno razoável em edifícios brasileiros. / The world is trying to move to a cleaner energy environment, especially on the electricity generation sector, which is responsible for a large share of CO2 emissions. In Brazil,crenewable energy sources are responsible for a great part of the electricity generation, but current changes in the Brazilian climate brought a necessity of diversification on the energy matrix. Then, distributed generation is a good way to diversify the Brazilian power matrix. Considering that cogeneration systems are distributed generation, and Brazilian buildings have need of cooling, due to the warm weather, the use of cogeneration equipped with an absorption or adsorption chiller could be beneficial. The trigeneration system is a highly efficient process, which can produce electricity, heating and cooling from the same primary energy source. However, there are really few researches concerning trigeneration systems in Brazil, especially on small and micro plants. Thus, this thesis will make and provide a technical and economical evaluation of small and micro trigeneration systems to different buildings under distinct tariff policies in Brazil. To do so, this work will optimize the sizing and monthly schedule the dispatch of the trigeneration systems to each one of the four study cases. Then, it will evaluate the maximum net present value (NPV) considering the variation of discount rate and US Dollar conversion rate. In the sequence, the grid dependence index (GDI), the discounted payback, the levelized cost of energy (LCOE) and the primary energy ratio (PER) to the best NPVs will be presented and analysed. As a result, this thesis will show that trigeneration plants can be profitable and can be certainly an efficient way to adopt a reliable and controllable distributed generation. Also, it will prove that it is possible to find situations in which the trigeneration plant can offer a high primary energy ratio, a fair levelized cost of energy, and in the meantime, it can provide financial savings with fair payback time in Brazilian buildings.
32

Novel DC/DC Converters For High-Power Distributed Power Systems

Francisco Venustiano, Canales Abarca 27 August 2003 (has links)
One of the requirements for the next generation of power supplies for distributed power systems (DPSs) is to achieve high power density with high efficiency. In the traditional front-end converter based on the two-stage approach for high-power three-phase DPSs, the DC-link voltage coming from the power factor correction (PFC) stage penalizes the second-stage DC/DC converter. This DC/DC converter not only has to meet the characteristics demanded by the load, but also must process energy with high efficiency, high reliability, high power density and low cost. To meet these requirements, approaches such as the series connection of converters and converters that reduce the voltage stress across the main devices have been proposed. In order to improve the characteristics of these solutions, this dissertation proposes high-efficiency, high-density DC/DC converters for high-power high-voltage applications. In the first part of the dissertation, a DC/DC converter based on a three-level structure and operated with pulse width modulation (PWM) phase-shift control is proposed. This new way to operate the three-level DC/DC converter allows soft-switching operation for the main devices. Zero-voltage switching (ZVS) and zero-voltage and zero-current switching (ZVZCS) soft-switching techniques are studied, analyzed and compared in order to improve the characteristics of the proposed converter. This results in a series of ZVS and ZVZCS three-level DC/DC converters for high-power high-voltage applications. In all cases, results from 6kW prototypes operating at 100 kHz are presented. In addition, with the ultimate goal of improving the power density of the DC/DC converter, a study of several resonant DC/DC converters that can operate at higher switching frequencies is presented. From this study, a three-element ZVS three-level resonant converter for applications with wide input voltage and load variations is proposed. Experimental results at 745 kHz obtained without penalizing the efficiency of the PWM approaches are presented. The second part of the dissertation proposes a quasi-integrated AC/DC three-phase converter that aims to reduce the complexity and cost of the traditional two-stage front-end converter. This converter improves the complexity/low-efficiency tradeoff characteristics evident in the two-stage approach and previous integrated converters. The principle of operation for the converter is analyzed and verified on a 3kW experimental prototype. / Ph. D.
33

Perspectiva de um sistema elétrico inteligente em uma cidade brasileira: estudo de caso Búzios / Perspective of an smart electrical system in brazilian city: Búzios case study

Lago, Renard Lopes Villas Boas do 08 February 2019 (has links)
Submitted by Nadir Basilio (nadirsb@uninove.br) on 2019-03-18T18:15:52Z No. of bitstreams: 1 Renard Lopes Villas Boas do Lago.pdf: 4581569 bytes, checksum: 9c4647056794f2f9266e721e689971ee (MD5) / Made available in DSpace on 2019-03-18T18:15:52Z (GMT). No. of bitstreams: 1 Renard Lopes Villas Boas do Lago.pdf: 4581569 bytes, checksum: 9c4647056794f2f9266e721e689971ee (MD5) Previous issue date: 2019-02-08 / In seeking the construction of an intelligent city there is a need to identify the processes that may or may not contribute to its construction and which challenges to overcome, taking into account the aspects of urban life, such as mobility, security, communication systems, sanitation and also for the electrical system. This research is a case study with the purpose of transforming Búzios into an intelligent city, as it is published by the municipal administration. The study aimed to verify if all the projects presented were executed and if the concepts of sustainability, rationality and loss control are being applied. The approach defined for research was qualitative, verifying the facts and seeking to clarify the dynamics of social relations, through a descriptive and exploratory research. During the visit to the city information was collected through interviews and direct observations, among the interviews were qualified 20 residents and collected 202 photographs. Among the projects implemented and in operation are three generators of photovoltaic energy, as for the projects implemented and that presented discontinuity and failures in its operation are the intelligent LED lighting system, the free internet system project, the projects with the systems of generation of aerogenerator energy, power network automation projects and installation projects of smart meters. During the technical visit, it was not possible to identify characteristics or contributions that define the city of Búzios-RJ, as the first intelligent city in Latin America, as little as an intelligent city, once the projects executed show flaws, a small part of the city was contemplated, the population does not have knowledge about the project, lack of continuity and governance. Although the projects listed make sense as components of an intelligent city with an intelligent electric grid, it was not possible to characterize the city as "intelligent" since the projects did not show, in their majority, effectiveness and scope enough to do so. The city can, however, become intelligent by expanding the reach and effectiveness of the projects. / Ao almejar a construção de uma cidade inteligente existe a necessidade de identificar os processos que podem ou não contribuir para sua construção e quais os desafios a serem superados, levando-se em conta os aspectos da vida urbana, como mobilidade, segurança, sistemas de comunicação, saneamento e também para o sistema elétrico. A presente pesquisa é um estudo de caso tendo como objeto a transformação de Búzios em cidade inteligente, conforme é divulgado pela administração municipal. O estudo teve como objetivo verificar se todos os projetos apresentados foram executados e se os conceitos de sustentabilidade, racionalidade e controle de perdas estão sendo aplicados. A abordagem definida para pesquisa foi qualitativa, verificando os fatos e buscando esclarecer a dinâmica das relações sociais, por meio de uma pesquisa descritiva e exploratória. Durante a visita a cidade foram coletadas informações por meio de entrevistas e observações diretas, dentre as entrevistas foram qualificados 20 moradores e coletadas 202 fotografias. Dentre os projetos implementados e em funcionamento estão três geradores de energia fotovoltaica, quanto aos projetos implementados e que apresentaram descontinuidade e falhas no seu funcionamento estão o sistema de iluminação a LED inteligente, o projeto de sistema de internet gratuita, os projetos com os sistemas de geração de energia aerogerador, os projetos de automação da rede de energia e os projetos da instalação dos medidores inteligentes. Durante a visita técnica não foi possível identificar características ou contribuições que definam a cidade de Búzios-RJ, como a primeira cidade inteligente da América Latina, tão pouco como cidade inteligente, uma vez que os projetos executados apresentaram falhas, uma pequena parte da cidade foi contemplada, a população não possui conhecimento sobre o projeto, falta de continuidade e de governança. Embora os projetos elencados façam sentido como componentes de uma cidade inteligente, com rede elétrica inteligente, não foi possível caracterizar a cidade como "inteligente" dado que os projetos não apresentaram, em sua maioria, efetividade e alcance suficiente para isso. A cidade pode, no entanto, tornar-se inteligente ao ampliar o alcance e a efetividade dos projetos.
34

Disturbance monitoring in distributed power systems

Glickman, Mark January 2007 (has links)
Power system generators are interconnected in a distributed network to allow sharing of power. If one of the generators cannot meet the power demand, spare power is diverted from neighbouring generators. However, this approach also allows for propagation of electric disturbances. An oscillation arising from a disturbance at a given generator site will affect the normal operation of neighbouring generators and might cause them to fail. Hours of production time will be lost in the time it takes to restart the power plant. If the disturbance is detected early, appropriate control measures can be applied to ensure system stability. The aim of this study is to improve existing algorithms that estimate the oscillation parameters from acquired generator data to detect potentially dangerous power system disturbances. When disturbances occur in power systems (due to load changes or faults), damped oscillations (or &quotmodes") are created. Modes which are heavily damped die out quickly and pose no threat to system stability. Lightly damped modes, by contrast, die out slowly and are more problematic. Of more concern still are &quotnegatively damped" modes which grow exponentially with time and can ultimately cause the power system to fail. Widespread blackouts are then possible. To avert power system failures it is necessary to monitor the damping of the oscillating modes. This thesis proposes a number of damping estimation algorithms for this task. If the damping is found to be very small or even negative, then additional damping needs to be introduced via appropriate control strategies. This thesis presents a number of new algorithms for estimating the damping of modal oscillations in power systems. The first of these algorithms uses multiple orthogonal sliding windows along with least-squares techniques to estimate the modal damping. This algorithm produces results which are superior to those of earlier sliding window algorithms (that use only one pair of sliding windows to estimate the damping). The second algorithm uses a different modification of the standard sliding window damping estimation algorithm - the algorithm exploits the fact that the Signal to Noise Ratio (SNR) within the Fourier transform of practical power system signals is typically constant across a wide frequency range. Accordingly, damping estimates are obtained at a range of frequencies and then averaged. The third algorithm applied to power system analysis is based on optimal estimation theory. It is computationally efficient and gives optimal accuracy, at least for modes which are well separated in frequency.
35

Optimal Location of Distributed Generation to Reduce Loss in Radial Distribution Networks

Sharma, Prashant Kumar January 2015 (has links) (PDF)
Power losses are always a cause of worry for any power grid. In India, the situation is even worse. Though recent reports by Ministry of Power shows that Aggregate Technical and Commercial losses (AT &C losses) have come down from 36.64% in 2002-03 to 27% in 2011-12, yet they are much higher than the losses seen in many of the developed nations. The reduction shown in power loss is because of the Electricity Act, 2003 and the amendments made to it in 2007 which controlled the commercial losses rather than the technical losses. According to Ministry of Power, technical losses (Transmission & Distribution losses or T&D losses) in India are reported to be 23.65% in 2011-12. However, according to the study done by EPRI, for systems deployed in developed countries, these losses are estimated to be in the range of 7-15.5%. T & D losses occur in four system components namely step-up transformers and high voltage transmission (0.5-1%), step down to in intermediate voltage, transmission and step down to sub transmission voltage level (1.5-3%), sub-transmission system and step down to low voltage for distribution (2-4.5%), and distribution lines (3-7%). 1% of power loss is approximately equivalent to annual loss of Rs 600 million for a single state. Hence, in a year, loss in distribution line alone causes approximate loss of Rs 1.8-4.2 billion per state. Understanding and reducing power losses in distribution lines which contribute nearly 50% of the total T&D losses assume significance and has formed the motivation for the work reported in the thesis. In recent years, the trend has been to encourage users to generate solar power predominantly at residential complexes and captive power plants at industrial complexes. It has been suggested in the literature that Distributed Generation (DG) can not only reduce the load demanded from the power grid but also the power loss. In this thesis, it has been shown that by the choice of proper size and location of DG, the power loss can be reduced substantially as compared to unplanned deployment of DGs. The objective of the thesis is to design strategy for location of distributed user generated power to maximize the reduction in power loss. The thesis begins with a study of distributed generation in primary distribution networks and proceeds to problem formulation, with the aim being to develop an algorithm that can find out the optimal locations for DG allocation in a network. A greedy approximation algorithm, named OPLODER (i.e. Optimal Locations for Distributed Energy Resources), is proposed for the same and its performance on a benchmark data set is observed, which is found to be satisfactory. The thesis then moves on to describe the actual data of 101,881 commercial, residential and industrial consumers of Bangalore metropolitan area. A loss model is discussed and is used to calculate the line losses in LV part of the grid and loss is estimated for the said actual data. The detailed analysis of the losses in the distribution network shows that in most cases the losses are correlated with the sanctioned load. However there are also some outliers indicating otherwise. The analysis concludes that the distributed generated sources need to be optimally located in order to benefit fully. Also presented thereafter is a study about the impact of electrical properties and the structure of the network on power loss. In the second part of the thesis, OPLODER was again used to process the BESCOM data of 101,881 consumers by modeling them to be connected in three topologies namely Bus (i.e. linear structure), Star (i.e. directly connected) and Hybrid (i.e. tree structure). In case of Bus topology, when DG capacity available is 5% of the demand in substation, OPLODER reduced the loss from 14.65% to 10.75%, from 11.63% to 7.71% and from 13.33% to 9.24% for IISc, Brindavan, and Gokula substations respectively. Similarly, for the same amount of DG in case of star topology, OPLODER reduced loss from 1.75% to 1.26%, from 3.39% to 2.59% and from 2.96% to 1.99% for IISc, Brindavan, and Gokula substations respectively. Thereafter, the available real world data is re-modeled as a tree-type structure which is closer to the real world distribution network and OPLODER is run on it. The results obtained are similar to those presented above and are highly encouraging. When applied to the three substations viz. IISc, Brindavan and Gokula, the power loss dips from 9.95% to 7.42%, from 6.01% to 4.44% and from 8.07% to 5.95%, in case of DG used is 5% of the demand in substation. For the optimal strategies worked out in the thesis, additional overheads will be present. These overheads are studied and it has been found that the present infrastructure and technologies will be sufficient to handle the smart distribution network and the optimal strategy for distributed sources.
36

Reactive Power Planning And Operation of Power Systems with Wind Farms for Voltage Stability Improvement

Moger, Tukaram January 2015 (has links) (PDF)
In recent years, the electric power industry around the world is changing continuously due to transformation from regulated market structure to deregulated market structure. The main aim of the transformation of electric supply industry under open access environment is to overcome the some of the limitations faced by the vertically integrated system. It is believed that this transformation will bring in new technologies, integration of other sources of energy such as wind, solar, fuel cells, bio-gas, etc., which are self sustainable and competitive, and better choice for the consumers and so on. As a result, several new issues and challenges have emerged. One of the main issues in power systems is to support reactive power for maintaining the system voltage profile with an acceptable margin of security and reliability required for system operation. In this context, the thesis addresses some of the problems related to planning and operation of reactive power in power systems. Studies are mainly focused on steady state operation of grid systems, grid connected wind farms and distribution systems as well. The reactive power support and loss allocation using Y-bus approach is proposed. It computes the reactive power contribution from various reactive sources to meet the reactive load demand and losses. Further, the allocation of reactive power loss to load or sink buses is also computed. Detailed case studies are carried out on 11-bus equivalent system of Indian southern region power grid under different loading conditions and also tested on 259-bus equivalent system of Indian western region power grid. A comparative analysis is also carried out with the proportional sharing principle and one of the circuit based approach in the literature to highlight the features of the proposed approach. A new reactive power loss index is proposed for identification of weak buses in the system. The new index is computed from the proposed Y-bus approach for the system under intact condition as well as some severe contingencies cases. Fuzzy logic approach is used to select the important and severe line contingencies from the contingency list. The validation of weak load buses identification from the proposed reactive power loss index with that from other well known existing methods in the literature such as Q-V sensitivity based modal analysis and continuation power flow method is carried out to demonstrate the effectiveness of the proposed index. Then, a short-term reactive power procurement/optimal reactive power dispatch analysis is also carried out to determine the optimum size of the reactive compensation devices to be placed at the weak buses for reactive compensation performance analysis in the system. The proposed approach is illustrated on a sample 5-bus system, and tested on sample 10-bus equivalent system and 72-bus equivalent system of Indian southern region power grid. A comprehensive power flow analysis of PQ type models for wind turbine generating units is presented. The different PQ type models of fixed/semi-variable speed wind turbine generating units are considered for the studies. In addition, the variable speed wind turbine generating units are considered in fixed power factor mode of operation. Based on these models, a comparative analysis is carried out to assess the impact of wind generation on distribution and transmission systems. 27-bus equivalent distribution test system, 93-bus equivalent test system and SR 297-bus equivalent grid connected wind system are considered for the studies. Lastly, reactive power coordination for voltage stability improvement in grid connected wind farms with different types of wind turbine generating units based on fuzzy logic approach is presented. In the proposed approach, the load bus voltage deviation is minimized by changing the reactive power controllers according to their sensitivity using fuzzy set theory. The fixed/semi-variable speed wind turbine generating units are also considered in the studies because of its impact on overall system voltage performance even though they do not support the system for voltage unlike variable speed wind generators. 297-bus equivalent and 417-bus equivalent grid connected wind systems are considered to present the simulation results. A comparative analysis is also carried out with the conventional linear programming based reactive power optimization technique to highlight the features of the proposed approach.
37

Index kvality napětí pro indikativní hodnocení kvality napětí v distribuční síti / Voltage quality index for distribution systems voltage quality benchmarking

Hausner, Josef January 2015 (has links)
This Master’s thesis deals with design of a new method for voltage quality benchmarking using voltage quality index. This index should determinate total voltage quality in the power grid and compare voltage quality in different places. There is design of several algorithms which value measured parameters in this thesis. The best suitable algorithm is selected. Program for this algorithm was compiled in GUI Matlab. The algorithm is verified by using measured parameters in this program. The last part of this thesis is focused on possible usage of created algorithm.
38

Frequency Stability of Power Electronic Based Power System with 100% Renewable Energy.

Albalali, Abdullah January 2022 (has links)
The modern power system is aiming to progress away from conventional synchronous machine  based power generation towards converter dominated system that leads to extensively high penetration of renewable energy such as wind and PV. This transition of modern power system toward converter based renewable energy comes with new challenges as the conventional synchronous generation is being replaced by converter based power system (CBPS). The converter is commonly interfaced to the power system with Phase Locked Loop (PLL) technique to synchronize the converter with the grid voltage angle and inject the current at the right angle. Therefore, this approach is called grid- ­following converter; this type of configuration of converters may lead to some power system instabilities (e.g., voltage instability, frequency instability, synchronous and sub­synchronous instabilities). In order to overcome the limitation of the grid-­following converters, another converter control concept become present in the literature as a grid-­forming converter where the synchronizing method to the grid eliminates the need for PLL .In this thesis, a grid- ­forming controlled power converter is implemented with an energy storage system to emulate the inertia of the synchronous generator through the VSM control concept. An electromagnetic transient (EMT) simulation has been modeled in the PSCAD simulation environment. The model is the well­known four-­machine two-­area power system. The model has been tested by incrementally replacing the synchronous machines with wind farms connected through power converters; this weakens the grid and may lead to frequency instability during a disturbing event. An Energy Storage System (ESS) has been implemented and added to the system to mitigate the loss of the kinetic energy of the rotating masses of the synchronous generators. The ESS is integrated with a grid-­forming converter that is controlled to mimic the dynamic behavior of a synchronous generator. Thus, the ESS is synchronized to the system based on the swing equation of the synchronous generator. The results show significant improvements in the frequency stability of the system under study. / Det moderna energisystemet har som mål att bortgå från den konventionella synkronmaskinbaserade energiförsörjning mot ett konverteringsdominerat system som leder till  en mycket hög penetration av förnybar energi, som tillexempel vind och solenergi. Den här övergången av modernt energisystem mot konverteringsbaserad förnybar energi medför nya utmaningar i och med att konventionell synkrongenerering byts ut mot konverterarbaserat energisystem (Converter Based Power System, CBPS) . Konverteraren är ofta integrerad i energisystemet via Phase Locked Loop ­teknik (PLL) för att synkronisera konverteraren med kraftnätets spänningsvinkel och injicera strömmen i rätt vinkel. Det här tillvägagångssättet kallas därför för nätföljande konvertering; denna typ av konfiguration av konverterare kan leda till instabilitet i energisystemet (t.ex. instabil elektrisk spänning, frekvensinstabilitet, synkron och sub- ­synkron instabilitet). För att hantera begränsningarna som nätföljande konverterare träder ett koncept om ytterligare en konverteringskontroll fram i litteratur, i form av en nätformande konverterare där synkroniseringsmetoden i nätet eliminerar behovet av PLL.I denna avhandling implementeras en nätformande konverterare med ett energiförvaringssystem för att emulera trögheten i synkrongeneratorn genom VSM-­styrkonceptet. En elektromagnetisk transientsimulering (EMT) har modellerats i simuleringsmiljön PSCAD. Modellen är det välkända energisystemet med fyra maskiner och två områden. Modellen har testats genom att stegvis byta ut synkronmaskinerna med vindkraftverk anslutna genom energikonverterare; detta gör nätet svagare och kan leda till frekvensinstabilitet vid en störande händelse. Ett energiförvaringssystem (Energy Storage System, ESS) har implementerats och kopplats till systemet för att mildra förlusten av kinetisk energi i de roterande massorna hos synkrongeneratorerna. Energiförvaringssystemet ESS är integrerat med en nätformande konverterare som styrs för att härma det dynamiska uppförandet av en synkrongenerator. Således är ESS synkroniserat med systemet baserat påsynkrongeneratorns svängekvation. Resultaten visar betydelsefulla förbättringar av frekvensstabiliteten i systemet under studien.
39

Informační a komunikační technologie v energetice / Information and communication technologies in energetics

Stavinoha, Jakub January 2008 (has links)
The thesis is focused on the information and communication technologies used in the energetic. Problematic areas in energetic which are regulation, metering, control of waste minimalizations, expense and maximalization of earnings. These aspects lead to implementing expert systems, which have to process this bulk of information necessary for increasing efficiency and economization of single processes. Systems used in practice have their own hierarchical structure, where every application requires specific access of selection of used components that suit to the application. First of all it is about acceptable device selection in single level of the system: metering and regulation, data acquisition out of the process and informative layer. Suitable choice flowing from previous, already settled up application is possible to reach maximum efficiency of the whole system. In the thesis there are introduced systems used in practice and possibilities of increase the effectiveness of generation, transmission and distribution with ICT usage in distributed power generation. We are mainly talking about upgrade processes joined with power generation of energy, diagnostics, isolation states on the power line and usage of expert systems for distribution.
40

Distributed generation for waste heat utilisation and industrial symbiosis at Zigrid AB. : A case study on the Alby hydrogen project in Ånge, Sweden

Abdlla, Hamodi, Eshete, Helen January 2023 (has links)
This thesis investigates the potential utilisation of Zigrid’s distributed power modules for waste heat utilisation and electricity production within an industrial cluster. The study examines generated waste heat from a hydrogen production plant with a PEM electrolyser and Zigrid’s innovative energy generation capabilities. Furthermore, the study investigates changes in the value chain within the industrial cluster when integrating Zigrid’s power modules as a cooling technique and thereby replacing cooling towers. This integration offers various potential avenues for the excess waste heat, such as electricity production and district heating. An in-depth economic evaluation was performed, weighing the cost-effectiveness of Zigrid's power modules against traditional cooling towers. The economic assessment includes the Levelized Cost of Electricity (LCOE) for locally produced electricity and showcase the potential savings by reducing dependence on the grid. Furthermore, the study also highlights the potential benefits of harnessing Sweden's waste heat, forecasting Zigrid's prospective contribution to local electricity generation and substantial economic efficiencies.  The study's findings underscore the viability of Zigrid's power units in increasing local electricity generation, curbing emissions, enhancing grid stability, and fostering sustainable practices within industrial clusters. / Denna avhandling undersöker potentialen för användning av Zigrids distribuerade kraftmoduler för utnyttjande av spillvärme och elproduktion inom ett industriellt kluster. Studien granskar genererad spillvärme från en väteproduktionsanläggning med en PEMelektrolysör och Zigrids innovativa energiproduktionsförmåga. Vidare undersöker studien förändringar i värdekedjan inom det industriella klustret när Zigrids kraftmoduler integreras som en kylteknik och därmed ersätter kyltorn. Denna integration erbjuder olika potentiella vägar för överskott av spillvärme, såsom elproduktion och fjärrvärme. En djupgående ekonomisk utvärdering genomfördes, där kostnadseffektiviteten hos Zigrids kraftmoduler jämfördes med traditionella kyltorn. Den ekonomiska bedömningen inkluderar den nivåbaserad elkostnaden (LCOE) för lokalt producerad elektricitet och visar de potentiella besparingarna genom att minska beroendet av elnätet. Vidare belyser studien också de potentiella fördelarna med att utnyttja Sveriges spillvärme och förutspår Zigrids framtida bidrag till lokal elproduktion och betydande ekonomisk effektivitet. Studiens resultat understryker Zigrids kraftenheters livskraftighet för att öka lokal elproduktion, minska utsläpp, förbättra nätstabiliteten och främja hållbara metoder inom industrikluster.

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