Due to historically low prices for electricity in Sweden, many small-scale hydropowerplants were closed down. A small-scale power plant has more or less the samemaintenance costs as larger plants, but doesn?t generate as much income. Today?sincreasing price for electricity in combination with a desire for renewable energysources makes small-scale hydropower interesting again.

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.

A large number of rivers in northern Sweden have hydropower developments that cause negative effects on both up- and downstream migrations of anadromous species like Atlantic salmon. So far, most attention has focused on the hindrances of adult fish during their upstream spawning migration. However, since turbines in Power stations cause losses on downstream passing fish, the focus on negative effects on smolts has increased. The aim of this study was to compare three different causes of losses of salmon smolts passing downstream through a Power station area in the flow-controlled River Åbyälven in northern Sweden.A total of 61 wild salmon smolts were caught and radio-tagged in the River Åbyälven during their downstream migration in June 2009. The salmon smolts were released at three locations, 1.1 km upstream from the Power station, in the turbine intake and in the upper part of a fishway, acting both for up- and downstream fish passage.

Jämtkraft AB which is a power production company in Sweden has bought two newhydro power units to their station in Hissmofors. The two new generators are using aconcept with sliding stator feet to handle the thermal expansion.The concept with sliding stator feet on hydro electric generators has not beenworking satisfactory on many hydro Power stations in Sweden and has caused a lot ofcosts due to long downtimes.The new station in Hissmofors is very important for Jämtkraft AB, and therefore theywant to know how to make sure that the sliding stator feet are working as theyshould. According to theories and a simplified model of the generator the stator feetdisplacement should be around 1 -1,6 mm.The generators are delivered with a surveillance system that will measure thedisplacement of the sliding stator feet. The signal from the system isn?t accessible forJämtkraft AB but it will alarm when the sliding stator feet are malfunctioning.To secure the function of the sliding feet a logger for the surveillance system or adifferent measurement system must be used; if both systems are used Jämtkraft cansecure the function of the surveillance system..

The increased travelling of today makes nodes along travelling routes more and more important. This is very much the case of petrol stations. They constitute important nodes in the road network, filling up thirsty fuel tanks and hungry stomachs, guiding road users and providing vehicle-services. In this thesis the role of the petrol station for road users was investigated in order to find out if the petrol station was a potential hot spot. We performed an ethnographic field study at a petrol station and found that a great number of visitor activities took place at the petrol station.

Upplands Väsby municipality has a vision that podcars in the future will become an effective alternative in public transport, with reduced car-dependency as a result. The system would also attract new inhabitants and businesses to the municipality.This report deals with various issues that podcar stations may face. Also, suggestions for possible track laying at the stations and station design are presented. Two areas are investigated. Eds allé which is a neighborhood that is planned for housing and where the station may be planned into the cityscape from the start.

Construction of an autonomous wind station was a project with the goal of creating a product that could collect wind data from a sensor and then transfer this data to a server wirelessly over the GSM network. The device would be powered by batteries and solar cells and function fully without requiring external power supply. This required that a small computer was constructed and programmed to store and send data at predetermined cycle times and programming of a server that received the sent data. The project also required optimization of power consumption and dimensioning of solar cells and batteries based on this. The construction of this station demanded research both for the selection of hardware and programming software. The computer was based on a microcontroller and a GSM module that sent the data over the 2G network.

The purpose of this essay is to study the role of web radio in Sweden. To fulfill the purpose we have done a case study of two Swedish radio stations: Sveriges Radio AB, which is a public service station, and a commercial station called Mix Megapol. By interviewing two persons from each station and analyzing the contents of their web sites, we have tried to see how the relationship between radio, Internet and web radio looks like. Thus, our method is qualitative. We have come to many conclusion of which some are: The new medium web radio borrows qualities from the traditional radio.

This project has revolved around finding better ways of overseeing vibrations of the gearbox at a wind Power station. The gearbox has been a huge problem at the stations located at Gässlingen and the sooner the warning of an incoming breakdown is at hand the more money you can save from preparations. The work has been carried out together with Askalon AB in cooperation with consults from ÅF. Askalon is a company with a department focused on overseeing vibrations and it is in collaboration with that department the work has been carried out. During this work, new positions for the sensors and new methods of gathering and analyzing data have been worked out. This was then implemented at a wind Power station to be tried out on site.

The upstream spawning migration of Atlantic salmon (Salmo salar) at the confluence area between the power-station outlet and the bypass-channel in river Umeälven (flow 430 m3s-1) was compared in 2004 and 2005, two years with different experimental flow-regimes. In 2004 the water flow in the bypass-channel was altered during the day with increased flows during the nights while the water flow in 2005 mainly was altered between the weekdays and weekends. Salmon showed altered migratory behaviour in this confluence area, assessed with telemetry (n=116) and echo-sounding, with up- or downstream responses depending on flow-changes in both the bypass and the Power station outlet. Increased turbine flow through the power-station generally attracted salmon into the tunnel outlet area while increased spill-flows facilitated salmon to enter the bypass. Echo-sounding in the confluence area showed an increased swimming activity up- and downstream due to time in the day and flow-rates through the tunnel outlet. No changes in activity could be detected due to increasing or decreasing flow through the hydro-power facility.

Vattenfall and Svenska Kraftnät perform start-up tests, where hydropower generators are used to power up the electrical grid in case of a blackout. To monitor the electrical grid, Phasor Measurement Units (PMU) are used. Each PMU is individually equipped with a GPS-receiver to precisely timestamp the data relative to the official time UTC. During the test, it is also of interest to timestamp the measurement signals from individual hydropower generators to later compare with PMU-data, and thus study the power grids impact on the generator. The aim is to work out an appropriate method to make these measurements and to build a data acquisition system, capable of timestamp data relative to UTC, from a generator in one of Vattenfalls hydroelectric Power stations. The problem is that the generator is located in an underground station which hampers the reception of GPS-signals and wiring should be avoided if possible. Time synchronization has been solved by using Vattenfalls network, which is synchronized by the network protocol NTP.

In Sweden there are 1894 small-scale hydropower plants in operation, which together generate 4.3 TWh of electricity per year according to Swedish hydropower compound (SVKF, 2011). This corresponds to the annual consumption of about 860,000 Swedish households (based on an annual consumption of 5000 kWh). In the mid-1950s there were around 4000 small-scale hydropower plants in operation in Sweden before cheap fossil fuels and uranium competed with them, in the current situation only 1,894 of these are in use. If slumbering small hydropower plants once again would be taken into use and some new ones are built, we would be able to extract about 7 TWh of renewable electricity from these annually in Sweden, representing about 1.4 million households.The thesis intends to calculate and construct a hydroelectric power plant at the existing dam in Olofsfors and give suggestions on how the Power station should run during the time that fish migration is greatest in Leduån.The turbine and generator to the station in Leduån at Olofsfors is designed by the height of the fall and the water flow through the dam. The turbine selected for the station is a CK-1000RM turbine with a 4-pole 250 kW generator from Cargo & power turbine Sweden AB, which is expected to deliver 1.2 GWh per year.

Wind power is one of the sources of renewable energy which has to be developed further in order to lessen our dependence on non renewable sources of energy. It's mainly oil and coal which have to be replaced by green energy. Wind power is already established in many countries, for example Germany, The United States of America and Denmark but it has to be continually developed and expanded to meet the needs of the growing energy consumption in the world. During the last few years many types of small wind turbines have appeared on the market. These small wind turbines are an alternative to the big wind turbines or power generators which demand huge sums of investment money.A new target group can now buy the small wind turbines in order to cover their own usage of electricity.

Hydropower is the largest renewable energy source available in today's society. Operation and production is handled by high-tech electronics. This thesis is done on behalf of Statkraft Sweden AB who wants to explore the possibility of replacing the hydraulic cylinder with an electric actuator, generally as well as a case of a small Power station on the river Nissan. Whether it is the chaplain or francis turbine vanes are actuated by hydraulic cylinders. Because of Gustavsberg hydropower is inconstant operation, this report is based on power calculations, which are read and computed according to the available hydraulic diagram.

The hydropower from Nissan River is of national interest and produces annually 230 GWh from the twelve Power stations in the main flow. For modified waters a consideration between the power production and the biological values has to be made. This reports serves as a pre-study for Nissans Vattenråd. It tries to evaluate some of the biological values in the Nissan basin and map the power production in the area. And the size and value of lost power production from new fishways for the twelve stations in the main flow.The investment of new fishways is calculated using simplified templates with values from the business.