This thesis focused on creating a model of a small hydropower plant model (SHPP) and a part of the electricity network in the simulation software "PSCAD" (basing on real sources). The model will be specified on the basis of the data obtained from the measurements to correspond with the real equipment.

This Master’s thesis focuses on calculation of power and temperature distribution in fuel assemblies of VVER-440 reactor at Dukovany Nuclear Power Plant. Theoretical section contains a brief description of VVER-440 technology, fuel and its development at Dukovany Nuclear Power Plant, basics of heat generation in nuclear reactors as well as an overview and categorization of computer codes, used for core calculations. Of these codes, the MOBY-DICK computer code is then described in depth, including its input and output files. The MOBY-DICK code is later on used for pinwise calculating power distribution of selected fuel cycles of defined units at Dukovany Nuclear Power Plant, with vizualization of output values for characteristic fuel assemblies. Results of this computation are then used for analysis, whether uneven power distribution in the core and heat generation gradient within fuel assemblies have any influence on measuring channel output temperatures, which is the pivotal part of this thesis.

This thesis deals with the analysis of warming and starting up the nuclear unit of Dukovany NPP after the outage. First part explains the various operating modes of nuclear power plants, specifically operating modes of Dukovany NPP. The following part contains the analysis of heat sources in the primary circuit and also the individual production and consumption of steam by the NPP. The next part deals with division into several points of the warming of the Dukovany NPP. The analysis of warming nuclear unit after a outage is made on the basis of the industry based data, measured in December 2015. The result of the analysis is determination the amount of steam passing from a another nuclear unit, which is following by the own proposal of the external steam source.

This diploma thesis introduces the reader to the possible types of electric energy storage technologies, their comparisons and utilization. After its introduction, it follows the description of individual technologies and principles that are currently meaningful and useful in practice. The thesis continues with the part characterizing the ways of using the accumulation in the grid. However, the main points of this thesis include the analysis of the influence of the photovoltaic installation on the specified distribution grid operation at the low voltage level and the analysis of the influence on the grid with connected accumulation. Another important objective was the model for the calculation of steady-state, which was programmed on the basis of the theory supported by the principles of production from intermittent sources and the principle of accumulation function. The outputs of the model in the form of the calculated voltage ratios at the individual supply points and current flows at the distribution transformer point were used to evaluate the analyzes mentioned above. The courses of the calculated parameters are broken down by different scenarios (according to the period, the degree of integration of production and the accumulation or the power output of the production), graphically processed and compared from the point of view of voltage fluctuations and changes in the power (or current) balance of the supply transformer.

The intermittent nature of renewable energy, variations in energy demand, and fluctuations in oil and gas prices have all contributed to variable demand for power generation from coal-burning power plants. The varying demand leads to load-follow and on/off operations referred to as cycling. Cycling causes transients of properties such as pressure and temperature within various components of the steam generation system. The transients can cause increased damage because of fatigue and creep-fatigue interactions shortening the life of components. The data-driven model based on artificial neural networks (ANN) is developed for the first time to estimate properties of the steam generator components during cycling operations of a power plant. This approach utilizes data from the Coal Creek Station power plant located in North Dakota, USA collected over 10 years with a 1-hour resolution. Cycling characteristics of the plant are identified using a time-series of gross power. The ANN model estimates the component properties, for a given gross power profile and initial conditions, as they vary during cycling operations. As a representative example, the ANN estimates are presented for the superheater outlet pressure, reheater inlet temperature, and flue gas temperature at the air heater inlet. The changes in these variables as a function of the gross power over the time duration are compared with measurements to assess the predictive capability of the model. Mean square errors of 4.49E-04 for superheater outlet pressure, 1.62E-03 for reheater inlet temperature, and 4.14E-04 for flue gas temperature at the air heater inlet were observed.

Durch den Ausbau insbesondere wetterabhängiger erneuerbarer Energien steigen zukünftig die Anforderungen an die Bereitstellung von Flexibilität im Stromsektor. Wärmespeicher und Power-to-Heat-Anlagen in der Fernwärmeversorgung können einen großen Beitrag zur Bereitstellung von Flexibilität an der Schnittstelle von Strom- und Wärmesektor liefern. Die vorliegende Arbeit untersucht vor dem Hintergrund von unterschiedlichen regulatorischen Rahmenbedingungen, an welchen Märkten der Einsatz der Power-to-Heat-Anlagen aus Systemsicht den größten Mehrwert zur Integration von erneuerbaren Energien liefern kann. Mithilfe des Strommarktmodells MICOES-Europe wird der stündliche Kraftwerkseinsatz aller europäischen Kraftwerke vor dem Hintergrund des Ausbaus der erneuerbaren Energien untersucht. Ziel der gemischt-ganzzahligen Optimierung, die insbesondere techno-ökonomische Charakteristika thermischer Kraftwerke berücksichtigt, ist die kostenminimale Deckung des Strombedarfs im Großhandelsmarkt bei gleichzeitiger Erfüllung der Leistungsvorhaltung für Regelenergie. In Deutschland werden die größten Fernwärmenetze mit ihren zugehörigen Erzeugungsanlagen (Kraft-Wärme-Kopplungsanlagen, Heizwerke, Wärmespeicher) abgebildet und stündlich die optimale Deckung des Wärmebedarfs berechnet. In einem Szenario für das Jahr 2025 wird die Verfügbarkeit von 1.000 MW an Elektrokesseln in großen deutschen Fernwärmenetzen angenommen. Hierbei wird deren Einsatz nur am Spotmarkt oder nur für negative Sekundärregelleistung dem Fall gegenübergestellt, dass die Anlagen auf beiden Märkten agieren und sich situationsabhängig zwischen ihnen entscheiden können. Es werden dabei die Fälle verglichen, bei denen Elektrokessel entweder Abgaben auf den Stromverbrauch zahlen oder keine zusätzlichen Abgaben tragen müssen. Der Einsatz der Elektrokessel in Verbindung mit Wärmespeichern in der Fernwärmeversorgung kann den Einsatz der KWK-Anlagen so flexibilisieren, dass sich deren Stromerzeugung stärker an die Einspeisesituation der erneuerbaren Energien anpassen kann. Auf diese Weise kann in allen betrachteten Szenarien die marktbedingte Abregelung von erneuerbaren Energien verringert werden. Dabei sinken die CO2-Emissionen der Strom- und Wärmeversorgung ebenfalls in allen Szenarien. Die größten Reduktionen sowohl bei CO2-Emissionen als auch bei den variablen Kosten der Strom- und Wärmeerzeugung werden dabei in den Szenarien mit Teilnahme der Elektrokessel am Regelleistungsmarkt erreicht. Stellen Elektrokessel negative Sekundärregelleistung bereit, kann hierdurch die Must-run-Erzeugung thermischer Kraftwerke in Stunden mit hoher Einspeisung von erneuerbaren Energien deutlich gesenkt werden. Hierdurch ergibt sich ein großer Hebel für die Integration von Strom aus erneuerbaren Energien. / The requirements for the provision of flexibility in the power sector will increase in the future due to the expansion of the usage of weather-dependent renewable energy sources. Heat storage and power-to-heat-plants (electric boilers) in the district heating supply can provide flexibility at the interface of the power and heat sector. At the moment the use of power-to-heat plants is only cost-effective on the control power market due to the current regulation. High charges for the direct use of electricity impede a use on the spot market. The present work examines from a system perspective on which market the use of electric boilers can provide the largest benefits for the integration of renewable energies considering different regu-latory frameworks. The year 2025 is considered where Germany aims to reach a share of 40 to 45 % renewable energy generation in the gross power consumption. For this purpose the hourly power plant dispatch of all European power plants is examined using the electricity market model MICOES-Europe. The model describes the wholesale electricity market and the control power market (secondary and tertiary reserve). The aim of the mixed-integer optimization is the calculation of the cost-minimal coverage of the electricity demand in the wholesale market while at the same time fulfilling the provision of control power. The optimization takes into account in particular the techno-economic characteristics of thermal power plants. In Germany, the largest district heating grids with their associated generation plants (combined heat and power plants, fossil-fuel and electric boilers, heat storage) are modelled and the optimal coverage of the heat demand is calculated for every hour. With the assumed payment of high electricity charges the use of electric boilers on the spot market is no business case in 2025. The situation changes in the scenario without electricity charges. Here, electric boilers reach between 1,050 and 2,140 full load hours. If the electric boilers provide negative secondary control power, the must-run generation of thermal power plants in hours with a high feed-in of renewable energies can be reduced significantly. This results in a large lever for the integration of renewable energies. Electric boilers reach up to 1,800 full load hours by providing control energy, if they provide control power all year round and without payment of electricity charges. The use of the electric boilers in combination with heat storages in the district heating system can make the dispatch of combined heat and power plants more flexible, so that their electricity generation can be better adapted to the feed-in situation of renewable energies. In this way, the market-dependent curtailment of renewable energies can be reduced in all scenarios. The CO2-emissions of the electricity and heat supply can be reduced by this technology in Germany. Furthermore, CO2-emissions in other European countries can be reduced as well due to effects of the power trade. The highest reductions in both CO2-emissions and variable costs of electricity and heat generation are achieved in the scenarios with electric boilers participating in the control power market.

This research work focuses on the reactive power compensation of the permanent magnet synchronous generator (PSG) in wind power plants. PSG feeds a fixed voltage dc grid through a rectifier bridge. In variable speed operation, the PSG will be able to build torque only in small speed range. This is due to the fixed magnet of the PSG. External reactive power compensation provides an attractive solution to overcome this problem. Different reactive power compensation configurations were examined. Statics synchronous series compensation and a shunt passive filter were chosen as a compensation method. Simulation and implementation of small wind power plant were performed. The wind power plant consists of the synchronous generator, inverter, rectifier, coupling transformers and shunt passive filter. The experimental results agree to the proposed theory and simulation results. / Der Schwerpunkt meiner Promotion ist die Blindleistungskompensation bei einem permanenterregten Synchrongenerator. Der Synchrongenerator speist das Gleichsspannungsnetz über ein Gleichrichter. In der Drehzahlvariablen Betriebsverhalten können Nachteile auftreten. Die Folge ist, dass bei konstanter Gleichspannung und fester Erregung durch die Permanenterregung nur ein sehr kleiner Drehzahlbereich mit vernünftiger Drehmomentausbeute bedienbar ist. Ein möglicher Ausweg wäre eine variable Kompensationsspannung. Verschiedene Kompensationsverfahren wurden untersucht. Ein Series Active Filter und ein Shunt Passive-Filter wurden als Blindleistungskompensation gewählt. Im Rahmen meiner Dissertation beschäftige ich mich mit dem Aufbau und der Simulation einer Windkraftanlage. Diese besteht aus einem permanenterregten Synchrongenerator, einem Wechselrichrter, einem Gleichrichter, drei Transformatoren und einem passiven Filter. Das Versuchsergebnis zeigt, dass die Theorie mit der Simulation übereinstimmt.

Virtual Power Plant (VPP) is a concept that aggregate Distributed Energy Resources (DER) together, aims to overcome the capacity limits of single DER and the intermit-ted natural characteristics of renewable energy sources like wind and solar. The whole system can be viewed as a single large-capacity power plant from the system‘s point of view. In this project, the literature review of VPP concept, architecture, existed project and the survey of VPP in Sweden are being conducted first. Secondly, the simplified VPP model is built on MATLAB/Simulink software. The simplified system contains a wind farm, a hydro power plant, a dynamic system load and an infinite bus representing the large transmission grid. During the simulation process, the generation and consump-tion unites are running according to the real history data located in external database. In the third place, optimized control schemes for the hydro unit in VPP model to decrease its effects on transmission grid are implemented in Simulink model. At the same time, hydro turbine should be controlled in an optimized way that without large turbulence. Basically, the hydro power plant is responsible for balancing the active power between the wind farm and dynamic load. Since there is a limit for the hydro turbine output, the rest of either power shortage or surplus power need to be com-pensated by the grid. This is the fundamental control scheme, so called run time con-trol scheme. The advanced control schemes here are based on the moving average control method and forecast compensation control method. The forecast compensa-tion control method use the 24 hours ahead load forecasting data generated by Artifi-cial Neural Network. Later on, analysis of those three control schemes will be pre-sented. The last part of the project is the conclusion of the different control schemes according to comparison of their control results.

The current shift towards renewable energy resources creates volatility in the electricity production that must be compensated by nevi sources of balancing energy. To ensure a normal operation of the power system, the transmission system operators procure power reserves able to provide regulation energy through market processes. Virtual power plants are now likely to participate on the balancing markets. In this study, the technical and economic feasibility of having virtual power plants participate in the Swiss balancing market is assessed. The study begins with the evaluation and compa.rison of four European balancing market designs and continues with the clarification of the concept of virtual power plant. The focus is then set on the Swiss ancillary services market, recently open to virtual pmver plants. After a detailed market description, an economic model simulating the participation of a virtual power plant made of industrial resources on the secondary and tertiary control markets has been developed. This model \Vas evaluated on an actual market design: the Sv.riss ancillary servicel:l market. 5 cases were simulated, allowing to estimate the opportunity fom both the capacity and the energy market productl:l. The simulations indicated that an example company (based on an actual situation) could hope a decrease in its energy cost between :3 and 4% by participating in a control pool over a year. Other simulations demonstrated the greater profit expected from secondary reserves compared to tertiary rel:lerves, and the need to develop an automatized activation system. The encouraging economic study is followed by a technical overview of the envisioned system. A generic technical characterization of virtual power plant is presented, on v.rhich the Swiss use-case is later applied. The breakdown into functional requirements allowed to highlight specific issues. The design of the control strategy, particularly to deliver secondary control, as well as the hardware communication interface to use are tvw aspects that ,vill require further analysis. Additionally, on an economic level, the investment cost for remote communication modules are acceptable with respect to the economic potentials estimated in the first part, for medium­sized industrial energy resources. In conclusion, the study established the profitability of an aggregation project on the Swisl:l market but also demonstrated the need to pursue research for the project to be fully feasible on a technical level.

Avstängda kärnkraftverk berövar många människor av elektricitet och det skulle ha en negativ inverkan både på företagets framtoning och mänskliga aktiviteter. På grund av detta behöver tillgängligheten av utrustningen i alla byggnaderna som kärnkraftverken består ses till. HVAC-system (Heating, Ventilation and Air Conditioning) spelar en viktig roll när det gäller tillgänglighet av utrustning eftersom dessa system ser till pålitligheten är på topp genom att anpassade omgivningsförhållanden till utrustningen. Att designa ventilationssystemet rätt är därför mycket viktigt och måste göras noggrant. Denna rapport introducerar metodologin för att designa och optimera ett ventilationssystem för en av byggnaderna i ett kärnkraftverk. Utöver detta utvecklas och beskrivs en metodologi för att designa ett rökkontrollssystem för en byggnad som ingår i kärnkraftverket. Dessa metodologier har implementerats för en byggnad i en demineraliseringsstation, Hinkley Point C project. / During nuclear power plants shutdown many people could be deprived of electricity and it would have a negative impact both on the company’s image and on people activities. As a consequence, availability of equipments in the different buildings which compose the power plant needs to be assured. HVAC system (Heating, Ventilation and Air Conditioning) plays an important role on the reliability of these equipments as it makes sure that ambient conditions in the buildings fit the operating temperature range of the equipments. Consequently sizing a ventilation system is really important and it needs to be carried out seriously. This paper introduces the methodology to size and optimize a ventilation system for nuclear power plants’ building. This paper also develops the methodology used to size a smoke control system in a nuclear related building. Direct application of this methodology has been realised for a specific building which is the demineralization station of Hinkley Point C project.