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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.
11

Otázka "Unbundlingu" v evropských debatách: jeho provedení a dopad na liberalizaci trhu se zemním plynem / The "Unbundling" issue in the center of European debates: its concept and impact on liberalisation of the gas market

Eliášová, Katarína January 2015 (has links)
Since long the energy policy has been escaping the concept of the common European policies or has been only partially influenced through the harmonisation of other common policies. If energy sector was considered an exclusive competence of every State Member (or as a part of its national security), nowadays, it has made a big step forward. At present, we talk about the establishment of a competitive internal energy market. The energy policy became part of the Community law only after the adoption of the Lisbon Treaty when the sector was granted a separate chapter and henceforth decided upon through a co-decisional procedure. The energy markets were subsequently given a new liberalisation impetus by the approval of the 3rd energy package (July 2009). My thesis focuses entirely on the natural gas sector and its crucial amendment to the network sector regulations. The core subject of the Directive 2009/73/EC concerning common rules for the internal market in natural gas is the ownership unbundling regime which stipulates the separation of production and sale operations from their transmission networks. This separation from the former vertically integrated utilities is supposed to guarantee an equal and non-discriminatory access to the transmission networks. Even though the ownership unbundling regime...
12

Hållbarhetscertifiering av anläggningsprojekt : En utvärdering av CEEQUAL i Svenska kraftnäts utbyggnad av transmissionsnätet / Sustainability assessment tools for certification of construction projects : An evaluation of using CEEQUAL in Svenska kraftnäts transmission projects

Stern, Cecilia January 2022 (has links)
Svenska kraftnät is the transmission system operator in Sweden, their responsibilities include renewing and expanding the existing transmission system to keep up with the rising demand for electricity. The ongoing climate crisis demands the process of expanding the transmission system to be as sustainable as possible. One way to do this is to use CEEQUAL, a point based, third party sustainability assessment tool for construction projects. The aim of this project is to estimate what CEEQUAL score the projects of Svenska kraftnät could achieve based on their current sustainability work. The aim also includes to determine what actions needs to be taken to improve that score, together with a cost analysis and interviews of the experiences from other CEEQUAL users.  By studying the sustainability work of Svenska kraftnät and translating this to CEEQUALs credits, a calculation of the current level of sustainability was determined as 44 percent. This equals the CEEQUAL level Pass. Further investigation revealed that to improve to the level Good, there needs to be more clear goals for a project sustainability and a business model for a circular economy among other things. For a higher score, reaching the level Very Good, there needs to be a life cycle analysis for new construction projects and better CO2-emission calculations.  A cost analysis revealed that it is hard to determine the cost of using CEEQUAL beforehand due to unforeseeable costs. Interviewing external users of CEEQUAL shows that using CEEQUAL is beneficial to improve the sustainability of a project and creates a common goal for the team members. A downside to using CEEQUAL is the administrative work it demands as well as the bureaucracy.  All in all, using CEEQUAL in all Svenska kraftnäts construction project could not be seen as beneficial. It would be beneficial to create a decision report tool for projects that help teams make sustainable choices for the projects. This would preferably be done together with distribution system operators in Sweden and transmission system operators in neighboring countries for a tool adapted to their operations and aspirations.
13

On Efficient Transmission Balancing Operation : Capturing the Normal State Frequency and Active Power Dynamics

Nilsson, Martin January 2018 (has links)
In an electric power system, there will always be an electric balance. Nevertheless, System Operators (SOs) often uses the term imbalance. Here, the term imbalance refers to the difference between trades and real-time measurements. This thesis defines the term imbalance and develops a framework helping SOs in finding better decisions controlling these imbalances.  Imbalances are controlled by many decisions made at various stages before real-time. A decision can be to increase the flexibility in production and consumption. However, this is not the only decision affecting real-time balancing operation. Other decisions are grid code requirements, such as ramp rates of HVDC and generation; balancing market structure, such as imbalance fees and trading period lengths; and the strategies used in the system-operational dispatch. The purpose of this thesis is to create a new possibility for SO to find decisions improving the balancing operation.  In order to find and compare decisions, the thesis develops a framework that evaluates many different decisions made at various stages before real-time. The framework consists of the following. First, it develops an intra-hour model using multi-bidding zone data from a historical time-period; able to capture the normal state frequency and active power dynamics. The model creates high-resolution data from low-resolution measurements using several data-processing methods. The uncertainty from the historical time-period is re-created using many sub-models with different input data, time-scales and activation times of reserves. Secondly, the framework validates the model and identifies system parameters based on simulated frequencies and frequency measurements in the normal state operation. Finally; new decisions' are modelled, tested, and evaluated on their impact on selected targets supporting corporate missions of the SOs. The goal of the framework is that it should be able to find better decisions for balancing operation but also that it should be applicable for real and large power systems. To verify this, the framework is tested on a synchronous area containing 11 bidding zones in northern Europe. Results show that the framework can be validated and trusted. Three new decisions, made at various stages before real time, have been modelled, tested and evaluated. The modelled decisions were (i) lower ramp rates for generation, (ii) increased capacities for automatic reserves, and (iii) a new strategy for the system-operational dispatch. One implication of applying the balancing evaluation framework on data from July 2015 is that all tested decisions improve several selected targets supporting the corporate missions of the SOs.  The conclusion is that the balancing framework is useful as a simulation tool in helping SOs in finding more efficient decisions for transmission system balancing operation. / <p>QC 20180116</p>
14

Vliv připojování disperzních zdrojů na DS 22 kV v dané oblasti a určení dopadů na provoz DS / Influence of Distributed Generation on Given Area of 22 kV Distribution Network

Samuel, Tomáš January 2010 (has links)
The Thesis deals with the current problem related to the connection of dispersive sources to the distribution network. The advantageous legislative support, however, gives a rapid rise to the sources of this kind. Current pricing philosophy favours in particular the growth of photovoltaic power plants. The introduction is aimed at the dispersive sources locating so as to give a comprehensive solution and better understanding of this issue. The equipments of this kind are located in accordance with legislation in force; however, it is necessary to formulate the possibilities of placing them from the view of rational use of the area with the aim of the public weal accordance of both public and private interests. Talking about connection of the new dispersive sources to the distribution network, it is important to mention the legislation, legal directives and regulations delimitating this kind of trade. This theme is the subject of another chapter of the work. Particular attention is paid to the regulation on conditions of connection to the distribution network. When connecting the sources to the distribution network the biggest technical problem from the view of electrical engineering is undesirable influence on the quality parameters (voltage) in this network. This is in particular the voltage change after connection, then, depending on the type of source, the emission of the current harmonic, sharp voltage change, etc. Considering current rise of the dispersive sources connected to the distribution network, more and more influence will appear in quantity parameters. For this reason there will be a lot of search for the methods of preventing from the negative influence on the network. From all of the above said reasons, the work is aimed at the operation analysis of the part of the distribution network, calculation of the network qualitative parameters and searching for the methods of negative influence rectification owing to switching processes of the distribution system. So as to determine the quantitative parameters we used the E-influence programme. Final paragraphs are devoted to the changes to come not only in legislation but, in general, in the approach of the distribution system operators not only to the ways of another connection of such sources but even the regulation of the dispersive sources already connected.

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