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3573 Uppsatser om Electric power line - Sida 2 av 239
Magnetfält alstrade kring nätstationer i samband med lokaldistribution av elkraft : Magnetic fields generated by electrical substations during distribution of electric power
Abstract: This report covers primarily the work of documenting electromagnetic fields generated by one of the later parts in the electrical power distribution chain: The electrical substation, wherein 10 kV is transformed to 400 V for use by private consumers. Thus it is one of the most widespread and frequently occurring parts in the Swedish power grid and of particular interest, as electrical substations are found everywhere in populated areas, often in close vicinity to people and animals.The report deals with a number of formulated questions and/or hypothesis? stated at the onset of the work undertaken, theory that is relevant for the topics the report covers, the details of the field work undertaken and the following analysis of the readings, which in term provide answers for the questions stated in the beginning. It also covers what is the currently known short term and long term risks associated with electromagnetic fields in the power frequent spectrum and of varying intensity in the vicinity of humans.The analysis also provides recommendations and identifies several points to carefully consider when planning for new installations or replacements of some parts of existing installations.For enhanced reading comprehension there is, aside from sections with pictures and attached explanatory texts and templates, several graphs, one-line diagram and maps of the power grid among the appendixes to the rapport..
"Fallbacks" - betydelsen av vandringstid för Atlantlax (Salmo salar L.) som faller nedströms vandringshinder
In Lake Vänern, Sweden, there is an endemic population of Atlantic salmon (Salmo salar L.) that lives its entire life in fresh water. The salmon is hindered from migrating to its natural spawning sites in the northern part of the River Klarälven by nine hydro-electric power plants. None of the hydro-electric power plants have fishways so that salmon migrating upstream or downstream may pass. In the current situation, the upward migrating salmon are caught in a fish trap at the most downstream located power plant in Forshaga. From there, the salmon are driven in a truck, past eight power plants and released a few kilometers upstream of the eighth power plant at Edsforsen.
Balansering av en storskalig vindkraftsutbyggnad i Sverige med hjälp av den svenska vattenkraften
This master thesis is a study of the Swedish hydropower capacity to balance wind power. The Swedish government has decided that it should be possible to produce 30 TWh from wind power in the year 2020. The Swedish municipalities have to have plans for wind power plants with total yearly generation of 30 TWh. Wind power is an variable energy source that needs to be balanced by other energy sources. In Sweden the Swedish hydropower can be used for balancing a large scale introduction of wind power.
Mobil kommunikation och högre tillgänglighet vid längre elavbrott : Exemplet stormen Dagmar och 4G-kommunikation inom smarta elnät
To be able to secure a safe and reliable power supply is becoming increasingly important since society depends on services and functions that need continuous power supply. The delivery rate in Swedish power supply is 99.98 % which insists on a high availability. During the past decade several storms has passed Sweden which resulted in large amount of tree felling leading to extended power outages. During these storms many socially critical activities, such as electric utility company Fortum, experienced disruption in mobile communication which affected the crisis management. This paper has investigated Swedish mobile operators? crisis management at Hi3G, Tele2 and TeliaSonera with a case study of the storm Dagmar that hit Sweden during December in 2011.
Acceptansgränsen för solceller i lågspänningsnät : Kan den ökas?
Microproduction, also called distributed generation, is something that has become more and more popular in the electric grid. Microproduction can however lead to unacceptable performance if several units are installed in the same low voltage network. It is therefore good to know a limit where the performance of the low voltage network becomes unacceptable based on given parameters. This limit is usually called hosting capacity.In this report the hosting capacity with respect to voltage and current have been studied in three low voltage networks which are located in Falu Elnäts concession area. This has been done by simulations in a GIS-program where critical times of the grid have been simulated.
Elbilen på väg mot 2030 : Handlingsplan för införande av elbilen i Sverige
The aim of this study is to examine possibilities and barriers for an introduction of electric vehicles in Sweden. The study has an interdisciplinary approach and thoroughly examines the essential topics which influence the future of the electric vehicle. The study reaches from answering the question on why electric vehicles lost the game to petrol cars in the early 20th century, to sketch how the difference in total cost of ownership will be between electric vehicles and petrol cars for the coming 20 years. Apart from these subjects the main topics of the study are today?s and tomorrow?s situation regarding technology, charging, fuel, market and economic incentives from an electric vehicle perspective.
Håller vindkraften vad den lovar?
The purpose of this study is to investigate how much of the estimated annual electric energy production from Swedish wind power that actually was produced, as well as the history of this agreement over time. The aim is to also examine if there are properties that have caused some group of wind power plants to produce more or less, compared to their estimated production. Operational data on wind turbines collected by the Swedish Energy Agency was analyzed. A survey was made among owners of wind power plants with a nominal power of at least 2 MW. Two different methods for normal year correction of production data were used and compared.
Konceptstudie av kombinerad nödgenerator-trädgårdsredskap : Concept Study of a Combined Emergency Generator-Garden tool
The present study concerns a concept development of a product idea that Bengt Magnuson, associate professor, had when a heavy storm caused a widespread power failure of long duration. With a basic power-producing unit one should be able to get through a power loss. The product could also be useful for other tasks if different modules are connected, e g grass mower or snow-blower.According to the product idea the basic unit will be able to produce electric power enough for a fridge, freezer, TV, and a few electric lamps. Normally the basic unit can be used e g as a mower, when such a module is attached. An increased number of tasks would make the contraption useful and tempting for those who do not own an electrical power set in reserve.
Affärsmöjligheter med Smarta Elnät : En studie som undersöker möjligheter och hinder i utvecklingen av det svenska elsystemet
Distributed, renewable generation-units and more efficient use of electric power,demands a developed electric grid. This grid is often referred to as the ?Smart Grid?.This future electric system rise expectations among actors in the existing electricmarket. International organizations share visions of opportunities for electricityconsumers and new actors, ready to enter the market. At the same time, electricutility companies may question the need for some of these upcoming changes, as theyare sometimes expected to lead the development.This paper therefore seeks to investigate the business opportunities related to SmartGrids.
Modellering och design av elmotor för mutterdragare
This thesis was carried out at Atlas Copco Tools and Assembly Systems. The purpose hasbeen to develop a design tool to be used for development of new electric motors for AtlasCopcos electric nutrunners. The focus of the thesis has been to increase productivity bydecreasing the power losses in an electric tool. The productivity is defined as themaximum number of tightenings a nutrunner can perform without becoming too hot.Before starting the development of this design tool an existing Matlab script, whichcalculates the losses in a slotless electric motor, has been studied and modified torepresent the real losses in a better way. The modification has been made by performingpractical studies of different losses and then adjusting existing parameters in the Matlabscript.Because design changes in one part of a mechatronic system can lead to a decrease inperformance of another part the choice of parameters that can be changed has been madeso that other parts of the system is affected as little as possible.A study of the existing tools efficiency during an entire tightening has been made toincrease the understanding of when and where the different losses appear and to comparethe modified Matlab script with the measured values.The design tool was formed so that it executes the Matlab script, that calculates thelosses, for a number of different design options and stores the alternative which producesthe least losses.
Power supply monitoring for wireless sensor platforms
Most of the portable electronic devices use a battery as a primary power source. Nowadays, when the applications are becoming smaller and smaller and more power efficient, the designer needs to concentrate more on reducing power consumption, using secondary power sources and introducing power storage devices. Multiple power source availability and a power storage device on the board will make the applications much more useful and efficient in everyday use. This thesis proposes a power supply unit (PSU) for wireless sensor platforms which is capable of supplying a sensor node with energy from multiple sources, as well as status information from the PSU. Present power storage devices, like electric double-layer capacitors (EDLCs) and batteries, have become more and more common as their characteristics have developed.
Implementering av en PSS i Trängslets kraftstation
The purpose of this master thesis is to implement and validate a Power System Stabilizer (PSS) to a generator at Trängslet hydropower station in Dalarna, Sweden. Problems with local rotor oscillations can occur at the hydropower station when power is transferred on a new power line (130 kV) from Northern to Southern part of Dalarna. To ensure good operation properties on this power line Fortum Generation AB and Fortum Distribution AB wants to activate a PSS on a generator.There have been investigations in which situations and what equipment that contributes to rotor oscillations. When this is known the PSS is tuned to damp these oscillations by choosing a good set of parameters. The most important parameters for good performance are to choose amount of gain and phase compensation.
Kraftkabelförläggning i mark : - en studie av produktionsmetoder
The assignment given to us by NCC was to compose a degree project based on ground excavations for power cables. The aim of the study was to examine suitable excavation methods depending on different possible terrain conditions. The amount of previously written material within this subject is nearly non- existent and therefore there is a genuine interest by the NCC to receive a compilation of different production methods. The greater part of this study is based upon interviews with several companies active within this area of expertise. The technique of placing the electricity grid beneath ground for safety is today getting more and more common.
End of line test : En studie av företaget Emotrons linjetestning i produktionen
Emotron is a company specialised in developing, producing and marketing equipment to con-trol, monitor and protect processes and machinery driven by electric motors, with an applica-tion focus. Examples of uses for their products are fans, pumps, lifts and cranes.The project is to look at Emotrons end of line test. The company has seen that at the final test-ing there is a bottleneck that restricts the outflow and prevents an increase in the number of tested products.The purpose of this project is to review how Emotrons end-of-line test works today and if there is a possibility to make the test more efficient in such a way that the quality is not at risk, while increasing the outflow of tested products.The projects first step is to look at and analyse what is causing the bottleneck at the end-of-line. When the analysis is complete, the next step is to review whether there is a possibility to solve the bottleneck and if so in what way can this be done. Emotrons most overall objective of the project is to increase the outflow of the number of tested products without jeopardizing the quality.An analysis has been made on frequency inverters, soft starters and shaft power monitors.
Vindkraft och elbilar på Öland år 2020 : Är smart laddning av elbilar lösningen på ett framtida flaskhalsproblem?
The Island of Öland has one of the best wind climates for land based wind power in Sweden. An objective for the Island is to become self sufficient using electricity from renewable source of energy such as wind. There is currently 55 MW capacity installed on the Island and it is estimated that grid congestion will occasionally occur if more than 135 MW was installed.The aim of this thesis is to investigate he possibilities for load management by smart charging of electric vehicles, EV. The definition of smart charging is that the charging is done to some extent with an ICT-system, (information and communication technology) that correlates wind electricity generation to the charging of electric vehicles. The purpose is to avoid grid congestions on the sub-sea cable that connects Öland to the mainland because that in turn would curtail wind energy production.