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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.
1

Die Anreizregulierung in der Elektrizitätswirtschaft Deutschlands : Positionen der staatlichen sowie privaten Akteure

Kleinwächter, Kai January 2011 (has links)
Die deutsche Energiewirtschaft befindet sich im Umbruch. Ein neuer staatlicher Ordnungsrahmen wurde geschaffen. Zentrales Element für die Regulierung der Stromnetze ist die „Anreizregulierung“ ‒ simulierter Wettbewerb, zentral gesteuert von der Bundesnetzagentur, um missbräuchliches Verhalten auszuschließen. Ausgehend von der Entwicklung des Energiemarktes seit dem 19. Jahrhundert analysiert Kai Kleinwächter die unterschiedlichen Interessen der Bundes- und Länderregierungen, der Stadtwerke sowie der großen Energiekonzerne bei der Einführung dieses Steuerungsinstrumentes. Bewertet werden auch die politischen Machtpotenziale der Akteure sowie ihr Einfluss auf den Gesetzgebungsprozess.
2

Electricity transmission line planning: Success factors for transmission system operators to reduce public opposition / Planung von Hochspannungsleitungen: Erfolgsfaktoren für Netzbetreiber zur Reduzierung des öffentlichen Widerstandes

Perras, Stefan 29 April 2015 (has links) (PDF)
Europe requires significant transmission grid expansions to foster the integration of electricity markets, enhance security of supply and integrate renewable energies. However, next to lengthy authorization processes, transmission system operators (TSOs) in Europe are currently facing extreme public opposition in their transmission line projects leading to significant project delays. These delays imply significant additional costs for TSOs as well as society as a whole and put the transformation of the European energy system at risk. Existing scientific literature currently lacks comprehensive studies that have tried to identify generalizable success factors to overcome public opposition in transmission line projects. The goal of work at hand was to close this research gap. Potential success factors were collected through extensive literature review and interviews throughout Europe with respective stakeholders such as citizen action groups, NGOs or energy experts. Experiences from analogue large infrastructure projects like wind parks, carbon capture and storage facilities, hydro dams, nuclear waste repositories, etc. were also used to form hypotheses. The findings were transformed into a structural equation model and tested through a questionnaire answered by almost all European TSOs. Results revealed that people’s trust in the TSO is of utmost importance for less public opposition. It can be regarded as the critical success factor per se. TSOs can create trust through stakeholder participation, sufficient communication, proper organizational readiness and liaison with stakeholders. Furthermore, appropriate technical planning can help to reduce public opposition in transmission line projects. In total 18 concrete and actionable success factors were identified for TSO management to facilitate the establishment of these aforementioned aspects. They will help European TSOs to reduce public opposition and thus accelerate the implementation of new transmission lines. Interestingly, economic benefits for people did not turn out to be a Significant success factor in reducing their opposition against new transmission lines.
3

The Stability and Control of Power Grids with High Renewable Energy Share

Auer, Sabine 29 March 2018 (has links)
Die vorliegende Dissertation untersucht die Stabilität und Regelung von Stromnetzen mit hohem Anteil Erneuerbarer Energien (EE). Dabei stehen drei Forschungsfragen, zu den neuartigen Herausforderungen für die zukünftige Stromnetzstabilität im Zuge der Energiewende, im Vordergrund. Erstens soll untersucht werden wie die Resilienz von Stromnetzen gemessen und im zweiten Schritt auch verbessert werden kann. Dabei zeige ich den notwendigen Detailgrad für transiente Stabilitätsuntersuchungen auf. Die zweite Frage lautet wie, trotz des zunehmenden Ausbaus von EE in Verteilnetzen, die statische Spannungsstabilität garantiert und Leitungsüberlastungen verhindert werden können. Hierfür analysiere ich mit einem konzeptionellen hierarchischen Verteilnetzmodell das zukünftige Potential für die Erzeugung von Blindleistung aus dezentralen Ressourcen am Beispiel Deutschlands. Die dritte Frage, wie eine dynamisch-stabile Integration von EE möglich ist, bildet den Hauptfokus meiner Dissertation. Dabei untersuche ich wie neuartige dynamische Aspekte EE, wie intermittente Fluktuationen oder auch Mess- und Reaktionszeiten von Leistungselektronik, die dynamische Netzstabilität beeinflussen und wie mögliche Instabilitäten durch Konzepte der Nachfragesteuerung behoben werden können. Dabei stoße ich bei der Analyse lokaler intermittenter Fluktuationen in ohmschen Verteilnetzen auf ein bemerkenswertes Wechselspiel zwischen Eigenschaften der Netzdynamik und -topologie. Als Zweites zeige ich wie mit der Einführung von Leistungselektronik und den damit verbundenen Mess- und Reaktionszeiten Resonanzkatastrophen hervorrufen werden können. Schließlich präsentiere ich wie die dezentrale Nachfragesteuerung von Elektroautos dynamische Instabilitäten, hervorgerufen durch Fluktuationen von EE, bereinigen kann. Zusammenfassend behandelt diese Arbeit verschiedene Aspekt zur Stabilität zukünftiger Stromnetze und integriert dabei sukzessive neuartige dynamische Aspekte von EE. / This PhD thesis is centered around the "Stability and Control of Power Grids with high Renewable Energy Share". With a conceptual modelers approach, I tackle three overarching questions related to the novel challenges the energy transition poses for the stability of future power grids. The first question focuses on how to measure and subsequently improve the resilience of a power grid. Here, I contribute important insights on the necessary model detail for transient stability assessments. The second question concerns how to ensure static voltage stability and avoid capacity overloading while the deployment of Renewable Energy Sources (RES) in the distribution grid layers is massively increasing. As a possible solution to this problem I analyze the future technical potential of reactive power provision from decentral resources in Germany. The third question, and main focus of this thesis, is on how to integrate renewable energies in a dynamically stable way. Specifically, I investigate the influence of intermittent RES and measurement delays from power electronic resources on frequency stability and how the latter can be restored by concepts of demand control. First, for local intermittent fluctuations in lossy distribution grids I find a remarkable and subtle but robust interplay of dynamical and topological properties, which is largely absent for lossless grids. Second, I show how delays may induce resonance catastrophes and how the existence of critical delays sets an upper limit for measurement times. Third and last, I present how the right parameterization of decentral electric vehicle control can completely overcome issues of short-term dynamic instability related to RES fluctuations. This control avoids demand synchronization and high battery stress. Altogether, this thesis investigates the stability of future power grids moving towards integrating more aspects of renewable energy dynamics. Finally, I point out open questions to encourage further research.
4

The Impact of Renewable Power Generation and Extreme Weather Events on the Stability and Resilience of AC Power Grids

Plietzsch, Anton 19 October 2022 (has links)
Der erste Teil dieser Arbeit beschäftigt sich mit der Frage, welchen Einfluss kurzzeitige Schwankungen der erneuerbaren Energiequellen auf die synchrone Netzfrequenz haben. Zu diesem Zweck wird eine lineare Antworttheorie für stochastische Störungen von dynamischen Systemen auf Netzwerken hergeleitet. Anschließend wird diese Theorie verwendet, um den Einfluss von kurzfristigen Wind- und Sonnenschwankungen auf die Netzdynamik zu analysieren. Hierbei wird gezeigt, dass die Frequenzantwort des Netzes weitestgehend homogen ist, aber die Anfälligkeit für Leistungsschwankungen aufgrund von Leitungsverlusten entlang des Leistungsflusses zunimmt. Der zweite Teil der Arbeit befasst sich mit der Modellierung von netzbildenden Wechselrichterregelungen. Bislang existiert kein universelles Modell zur Beschreibung der kollektiven Dynamik solcher Systeme. Um dies zu erreichen, wird unter Ausnutzung der inhärenten Symmetrie des synchronen Betriebszustandes eine Normalform für netzbildende Akteure abgeleitet. Anschließend wird gezeigt, dass dieses Modell eine gute Annäherung an typische Wechselrichter-Dynamiken bietet, aber auch für eine datengesteuerte Modellierung gut geeignet ist. Der letzte Teil der Arbeit befasst sich mit der Analyse des Risikos von Stromausfällen, welche durch Hurrikans verursacht werden. Hohe Windgeschwindigkeiten verursachen häufig Schäden an der Übertragungsinfrastruktur, welche wiederum zu Überlastungen anderer Komponenten führen und damit eine Kaskade von Ausfällen im gesamten Netz auslösen können. Simulationen solcher Szenarien werden durch die Kombination eines meteorologischen Windmodells sowie eines Modells für kaskadierende Leitungsausfälle durchgeführt. Durch Monte-Carlo-Simulationen in einer synthetischen Nachbildung des texanischen Übertragungsnetzes können einzelne kritische Leitungen identifiziert werden, welche zu großflächigen Stromausfällen führen. / The first part of this thesis addresses the question which impact short-term renewable fluctuations have on the synchronous grid frequency. For this purpose, a linear response theory for stochastic perturbations of networked dynamical systems is derived. This theory is then used to analyze the impact of short-term wind and solar fluctuations on the grid frequency. It is shown that while the network frequency response is mainly homogenous, the susceptibility to power fluctuations is increasing along the power flow due to transmission line losses. The second part of the thesis is concerned with modeling grid-forming inverter controls. So far there exists no universal model for studying the collective dynamics of such systems. By utilizing the inherent symmetry of the synchronous operating state, a normal form for grid-forming actors is derived. It is shown that this model provides a useful approximation of certain inverter control dynamics but is also well-suited for a data-driven modeling approach. The last part of the thesis deals with analyzing the risk of hurricane-induced power outages. High wind speeds often cause damage to transmission infrastructure which can lead to overloads of other components and thereby induce a cascade of failures spreading through the entire grid. Simulations of such scenarios are implemented by combining a meteorological wind field model with a model for cascading line failures. Using Monte Carlo simulations in a synthetic test case resembling the Texas transmission system, it is possible to identify critical lines that trigger large-scale power outages.
5

Electricity transmission line planning: Success factors for transmission system operators to reduce public opposition

Perras, Stefan 26 February 2015 (has links)
Europe requires significant transmission grid expansions to foster the integration of electricity markets, enhance security of supply and integrate renewable energies. However, next to lengthy authorization processes, transmission system operators (TSOs) in Europe are currently facing extreme public opposition in their transmission line projects leading to significant project delays. These delays imply significant additional costs for TSOs as well as society as a whole and put the transformation of the European energy system at risk. Existing scientific literature currently lacks comprehensive studies that have tried to identify generalizable success factors to overcome public opposition in transmission line projects. The goal of work at hand was to close this research gap. Potential success factors were collected through extensive literature review and interviews throughout Europe with respective stakeholders such as citizen action groups, NGOs or energy experts. Experiences from analogue large infrastructure projects like wind parks, carbon capture and storage facilities, hydro dams, nuclear waste repositories, etc. were also used to form hypotheses. The findings were transformed into a structural equation model and tested through a questionnaire answered by almost all European TSOs. Results revealed that people’s trust in the TSO is of utmost importance for less public opposition. It can be regarded as the critical success factor per se. TSOs can create trust through stakeholder participation, sufficient communication, proper organizational readiness and liaison with stakeholders. Furthermore, appropriate technical planning can help to reduce public opposition in transmission line projects. In total 18 concrete and actionable success factors were identified for TSO management to facilitate the establishment of these aforementioned aspects. They will help European TSOs to reduce public opposition and thus accelerate the implementation of new transmission lines. Interestingly, economic benefits for people did not turn out to be a Significant success factor in reducing their opposition against new transmission lines.:Contents I List of tables VIII List of figures IX List of abbreviations XI List of symbols XV List of country codes XVI 1 Introduction 1 1.1 Problem statement 1 1.2 Thematic classification and research gap 2 1.3 Objective, research questions and scop e of work 3 1.4 Methodology and structure of work 5 2 Fundamentals of electricity transmission line planning 7 2.1 History of the European electricity transmission network 7 2.2 Transmission technologies 9 2.2.1 High-voltage alternating current (HVAC) 9 2.2.1.1 High - voltage alternating current overhead lines (HVAC OHL) 9 2.2.1.2 High - voltage alternating underground cables (HVAC UGC) 10 2.2.2 High - voltage direct current (HVDC) 12 2.2.2.1 High - voltage direct current overhead lines (HVDC OHL) 12 2.2.2.2 High - voltage direct current underground cables (HVDC UGC) 13 2.2.3 Gas - insulated lines (GIL) 14 2.3 Major players 15 2.3.1 European Transmission System Operators (TSOs) and related associations 15 2.3.1.1 National Transmission System Operators (TSOs) 15 2.3.1.2 ENTSO - E 16 2.3.2 Energy regulators and related associations 18 2.3.2.1 National regulatory authorities (NRA) 18 2.3.2.2 European associations of energy regulators 19 2.4 Development of new transmission lines 20 2.4.1 Planning objectives 20 2.4.2 Planning process 21 2.4.2.1 Identification of needs 22 2.4.2.2 Feasibility study 23 2.4.2.3 Spatial planning 24 2.4.2.4 Strategic Environmental Assessment (SEA) 25 2.4.2.5 Environmental Impact Assessment (EIA) 26 2.4.2.6 Permitting procedure 28 2.4.2.7 Securing land rights and way - leaves 28 2.4.2.8 Construction, commissioning and operation 29 2.5 Project delays and obstacles 31 2.5.1 Project delays 31 2.5.2 Rationales for delay 33 2.5.2.1 Minor obstacles 34 2.5.2.2 Public opposition 35 2.5.2.3 Insufficient authorization procedures 36 2.5.3 Excursus: Recent governmental measures to overcome delays 38 2.5.3.1 Austria 38 2.5.3.2 Denmark 38 2.5.3.3 Germany 39 2.5.3.4 Great Britain 41 2.5.3.5 Netherlands 42 2.5.3.6 European Union 43 2.5.3.7 Further recommendations 48 2.6 Interim conclusion on the fundamentals of transmission line planning 49 3 Fundamentals of social acceptance 51 3.1 Definition and classification 51 3.2 Contextual factors that influence stakeholders’ attitudes 54 3.2.1 Proximity of stakeholders to a facility 54 3.2.2 Risk perception of individuals 55 3.2.3 Individual knowledge base 56 3.2.4 Existing and marginal exposure 56 3.2.5 Land valuation and heritage 57 3.2.6 Trust in project developer 58 3.2.7 Energy system development level 59 3.3 The history of social movement against infrastructure facilities 60 3.4 Forms of public opposition 61 3.5 Interim conclusion on the fundamentals of social acceptance 63 4 Fundamentals and methodology of success factor research 64 4.1 The goal of success factor research 64 4.2 Defining success factor terminology 64 4.2.1 Success 64 4.2.2 Success factors 65 4.3 Success factor research history and current state 67 4.4 Classification of success factor studies 67 4.4.1 Specificity 68 4.4.2 Causality 69 4.5 Success factor identification approaches 70 4.5.1 Systematization of success factor identification approaches 70 4.5.2 Approach assessment 72 4.6 Criti cism to success factor research 73 4.7 Interim conclusion on the fundamentals of success factor research 75 5 Success factor res earch on social acceptance in transmission line planning – a combination of research streams 77 5.1 State of research 77 5.1.1 Social acceptance in electricity transmission line planning (A) 77 5.1.2 Success factor research on social acceptance (B) 83 5.1.3 Success factor research in transmission line planning (C) 89 5.2 Value add and classification of this work 89 5.3 Research design 90 5.3.1 Identification of potential success factors through a direct, qualitative - explorative approach 92 5.3.1.1 Overview of methodologies 92 5.3.1.2 Survey 93 5.3.2 Quantitative - confirmatory approach to validate potential success factors 95 5.3.2.1 Overview of statistical methodologies 95 5.3.2.2 Structural equation modeling (SEM) 96 5.3.2.2.1 Path analysis 97 5.3.2.2.2 Structure of SEM 99 5.3.2.2.3 Methods for SEM estimation 102 5.3.2.2.4 PLS algorithm 106 6 Identification of reasons for public opposition and derivation of potential success factors 112 6.1 Conducted interviews 112 6.1.1 Selection of interviewees 112 6.1.2 Preparation, conduction and documentation of interviews 115 6.2 Reasons for public opposition 117 6.2.1 Health and safety issues 118 6.2.1.1 Electric and magnetic fields (EMF) 118 6.2.1.2 Falling ice 124 6.2.1.3 Toppled pylons and ruptured conductors 125 6.2.1.4 Flashover 125 6.2.2 Reduced quality of living 126 6.2.2.1 Visual impact 126 6.2.2.2 Noise 128 6.2.3 Economic unfairness 130 6.2.3.1 Devaluation of property and insufficient compensation 130 6.2.3.2 Expropriation 131 6.2.3.3 Negative impact on tourism 132 6.2.3.4 Lack of direct benefits and distributional unfairness 132 6.2.3.5 Agricultural disadvantages 133 6.2.4 Lack of transparency and communication 135 6.2.4.1 Insufficient justification of line need 135 6.2.4.2 Insufficient, inaccurate and late information 137 6.2.4.3 Intransparent decision making 138 6.2.4.4 Inappropriate appearance 138 6.2.4.5 Expert dilemma 139 6.2.5 Lack of public participation 140 6.2.5.1 Lack of involvement 140 6.2.5.2 One - way communication 141 6.2.5.3 Lack of bindingness 141 6.2.5.4 Inflexibility 142 6.2.6 Environmental impact 142 6.2.6.1 Flora 143 6.2.6.2 Fauna 145 6.2.7 Distrust 146 6.3 Potential success factors to reduce public opposition 147 6.3.1 Communication 149 6.3.1.1 Communication strategy 149 6.3.1.2 Early communication 150 6.3.1.3 Line justification 150 6.3.1.4 Direct personal conversation 151 6.3.1.5 Appropriate communication mix 153 6.3.1.6 Comprehensibility 156 6.3.1.7 Sufficient and honest information 157 6.3.1.8 Stakeholder education 158 6.3.1.9 Post - communication 159 6.3.2 Participation 160 6.3.2.1 Pre - polls 160 6.3.2.2 Participation possibilities 161 6.3.2.3 Participation information 164 6.3.2.4 Macro - planning involvement 165 6.3.2.5 Pre - application involvement 166 6.3.2.6 Neutral moderation/mediation 166 6.3.2.7 Joint fact finding 169 6.3.2.8 Flexibility, openness and respect 170 6.3.2.9 Commitment and bindingness 171 6.3.2.10 Transparent decision making 172 6.3.3 Economic benefits 173 6.3.3.1 Local benefits 173 6.3.3.2 Individual compensations 174 6.3.3.3 Muni cipality compensations 176 6.3.3.4 Socio - economic benefits 177 6.3.3.5 Excursus: Social cost - benefit analysis of a new HVDC line between France and Spain 177 6.3.4 Organizational readiness 182 6.3.4.1 Stakeholder analysis and management 182 6.3.4.2 Qualification and development 184 6.3.4.3 Sufficient resources 186 6.3.4.4 Internal coordination 187 6.3.4.5 Cultural change 187 6.3.4.6 Top - management support 188 6.3.4.7 Best practice exchange 188 6.3.5 Stakeholder liaison 189 6.3.5.1 Stakeholder cooperation 189 6.3.5.2 Supporters / Multiplicators 190 6.3.5.3 Local empowerment 191 6.3.6 Technical planning 191 6.3.6.1 Line avoidance options 191 6.3.6.2 Route alternatives 194 6.3.6.3 Transmission technology options 194 6.3.6.4 Piloting of innovations 198 6.3.6.5 Excursus: Exemplary transmission line innovations 198 6.3.6.6 Avoidance of sensitive areas 206 6.3.6.7 Bundling of infrastructure 206 6.3.6.8 Line deconstruction 207 6.3.6.9 Regulatory overachievement 208 7. Development of research model 209 7.1 Procedure 209 7.2 Development of hypotheses on causal relationships 209 7.2.1 Stakeholder liaison 209 7.2.2 Participation 210 7.2.3 Communication 210 7.2.4 Organizational readiness 211 7.2.5 Economic benefits 212 7.2.6 Technical planning 212 7.2.7 Trust 213 7.2.8 Summary of hypotheses 213 7.3 Development of path diagram and model specification 214 7.3.1 Structural model 214 7.3.2 Measurement model 215 7.3.2.1 Formative measurements 215 7.3.2.2 Reflective measurements 2 7.4 Identifiability of model structure 217 8 Empirical validation of potential success factors 219 8.1 Data acqu isition 219 8.1.1 Concept of using questionnaires for data acquisition 219 8.1.2 Target group and sample size 220 8.1.3 Questionnaire design 222 8.1.3.1 Form and structure 222 8.1.3.2 Operatio nalization 224 8.1.3.2.1 Operationalization of potential success factors 224 8.1.3.2.2 Operationalization of construct TRUST 225 8.1.3.2.3 Operationalization of construct REDUCED PUBLIC OPPOSITION 226 8.1.3.2.4 Operationalization of control variables 226 8.1.3.3 Bias 227 8.1.3.3.1 Common method bias 227 8.1.3.3.2 Key i nformation bias 229 8.1.3.3.3 Hypothetical bias 229 8.1.4 Pretest 230 8.1.5 Questionnaire return and data preparation 231 8.2 Model estimation 236 8.2.1 Software selection for modeling 236 8.2.2 Estimation results 237 8.3 Model evaluation 239 8.3.1 Evaluat ion of reflective measurement models 240 8.3.1.1 Content validity 240 8.3.1.2 Indicator reliability 243 8.3.1.3 Construct validity 245 8.3.1.3.1 Convergent validity 245 8.3.1.3.1.1 Average var iance extracted (AVE) 245 8.3.1.3.1.2 Construct reliability 245 8.3.1.3.2 Discriminant validity 247 8.3.1.3.2.1 Fornell/Larcker criterion 247 8.3.1.3.2.2 Cross loadings 248 8.3.2 Evaluation of formative measurement models 250 8.3.2.1 Content validity 250 8.3.2.2 Indicator reliability / relevance 250 8.3.2.2.1 Indicator weights and significance 250 8.3.2.2.2 Multicollinearity 254 8.3.2.3 Construct validity 256 8.3.3 Evaluation of structural model 256 8.3.3.1 Multicollinearity 256 8.3.3.2 Explanatory power 257 8.3.3.3 Predictive relevance 259 8.3.4 Evaluation of total model 260 8.4 Verification of hypotheses and discussion of results 260 8.5 Success factors for reducing public opposition in transmission line planning: Recommendations for TSO management 264 8.5.1 Measures to create stakeholder trust 266 8.5.1.1 Sufficient stakeholder participation 266 8.5.1.2 Proper stakeholder communication 267 8.5.1.3 TSO’s organizational readiness for stakeholder management 267 8.5.1.4 Creating liaison with stakeholders 268 8.5.2 Important aspects in technical planning 268 8.5.3 Consolidated overview 269 9 Concluding remarks 270 9.1 Summary of results 270 9.2 Contribution, limitations, and directions for further research 272 10 Appendix 276
6

Inferring Topology of Networks With Hidden Dynamic Variables

Schmidt, Raoul, Haehne, Hauke, Hillmann, Laura, Casadiego, Jose, Witthaut, Dirk, Schäfer, Benjamin, Timme, Marc 04 June 2024 (has links)
nferring the network topology from the dynamics of interacting units constitutes a topical challenge that drives research on its theory and applications across physics, mathematics, biology, and engineering. Most current inference methods rely on time series data recorded from all dynamical variables in the system. In applications, often only some of these time series are accessible, while other units or variables of all units are hidden, i.e. inaccessible or unobserved. For instance, in AC power grids, frequency measurements often are easily available whereas determining the phase relations among the oscillatory units requires much more effort. Here, we propose a network inference method that allows to reconstruct the full network topology even if all units exhibit hidden variables. We illustrate the approach in terms of a basic AC power grid model with two variables per node, the local phase angle and the local instantaneous frequency. Based solely on frequency measurements, we infer the underlying network topology as well as the relative phases that are inaccessible to measurement. The presented method may be enhanced to include systems with more complex coupling functions and additional parameters such as losses in power grid models. These results may thus contribute towards developing and applying novel network inference approaches in engineering, biology and beyond.

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