This master thesis has been performed at Vattenfall Power Consultant in Gothenburg and Trollhättan for Vattenfall Vattenkraft. In this report vacuum circuit breaker in small-scale Hydropower stations with the rated power 4 MVA and below has been studied. Models of the stations are modeled and analyzed in PSCAD/EMTDC to study the high voltage transients that are created after current chopping with vacuum circuit breaker. Vacuum circuit breaker may chop the current before it reaches zero value, which means that high voltage transients can be created. The equipment of the stations can be destroyed by high voltage transients.The purpose of this thesis is to examine the use of vacuum circuit breaker in small-scale Hydropower stations and the risk for high voltage transients from current chopping.According to the results there is a risk of high voltage transients after current chopping with small synchronous generators in stations with the operating voltages 0.4 kV and 3.6 kV.

This master thesis covers the seasonal planning of a small scale hydropower system. The system in this study is owned and operated by Mälarenergi Vattenkraft AB. The total system consists of 4 different main rivers with 24 Hydropower stations and several dams. The total installed power in the system is 43.75 MW. Most of the Hydropower stations are regarded as small scale Hydropower stations and thus entitled to green certificates.In this report the issue of planning is formulated as an optimization problem.

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.

The purpose with this thesis work was to design and build a technical aid for installingbatteries in telecom base stations. Today that job is done manually, since there is noequipment on the market for that purpose. Installing batteries in base stations manually isa very tough job.To get ideas for possible solutions a preliminary study on existing lift aids was done.From the preliminary study the conclusion that some kind of overhead crane would besuitable for the task was drawn. After that a lift for installing batteries in base stationswas designed, built and tested. The tests show that it is possible to minimize heavy liftingwhen installing batteries in telecom base stations, at a relatively low cost.ii.

AbstractThis report is made in cooperation with the municipality of Vasteras and technical committeestaff. The report addresses several topics that affect fuel stations in Vasteras. The reportcontains two parts, first is a inventory that review all stations in the area to be addressed. Theinventory is made with consideration to various things that geographic situation, whatcompanies are represented and what level of service stations have. And the second part of thereport, is done with the analysis of how it looks in daily situations review.

The purpose of this project was to produce signal relay stations that could receive information via 2.4 GHz radio and relay the information to a designated target station. If a relay station was located outside of signal range for the target station it was supposed to utilize other relay stations to transfer the information to the target station, so called multi-hop.The would-be application of the relay stations was orienteering. When an orienteer punches a checkpoint the signal stations would relay information of who punched the control, when it was punched and the checkpoint that was punched to the speaker tower in the goal area.The work resulted in prototypes which fulfilled the statement of purpose and was tested at an orienteering competition with satisfactory results. The performance of the prototypes was tested and found adequate for the would-be application..

AbstractThis report is made in cooperation with the municipality of Vasteras and technical committeestaff. The report addresses several topics that affect fuel stations in Vasteras. The reportcontains two parts, first is a inventory that review all stations in the area to be addressed. Theinventory is made with consideration to various things that geographic situation, whatcompanies are represented and what level of service stations have. And the second part of thereport, is done with the analysis of how it looks in daily situations review.

This study focuses on small scale hydropower in Sweden. This means plants with a capacity of up to 10 MW. The study has a special focus on plants with a capacity up to 2 MW. The study has three aims. It strives to describe the small-scale hydroelectric industry in Sweden.

The names of railway stations and halts along the earliest railway lines on Lithuanian territory have been studied, i.e. along those railway lines built between 1861 and 1873. Especially, attention has been drawn to names that are not obvious regarding the geographical location of the station or halt. Some 50 percent of the names are showing some kind of irregularity in this respect. Most common (about 30 examples) are stations or halts that are serving a population centre situated at some distance from the station, but still bearing the name of that population centre.

The purpose of this study is to see how five different local radio stations, P4, within the public service organization Sveriges Radio communicate with their listeners through Facebook and how they differ from each other.We have also studied how the radio stations follow Sveriges Radios? policies for socialmedia usage and how the communication through Facebook can benefit thetraditional radio. Our study contains a combination of quantitative content analysis with qualitative interviews. We studied the five stations? Facebook pages from for the quantitative content analysis and interviewed those who were responsible for the social media pages, such as web editors and channel managers.Our conclusions are that the P4-stations communicate through Facebook to create a dialogue with the listeners and to reach two-way communication; the stations published mostly written updates that encouraged interactivity.

When the producers? responsibility for packaging was introduced in Sweden in 1994 the industry set up public recycling stations to facilitate the collection of the waste material. In order to establish recycling stations at suitable locations the municipalities assist the industry?s service organization for operation of the recycling stations, the Package and Newspaper Collection Service (Förpacknings- och tidningsinsamlingen, FTI). The objectives of this thesis are to improve the service of the public recycling stations within Lidingö town and to increase the accessibility to these stations for the inhabitants of Lidingö.

The invasive species raccoon dog (Nyctereutes procyonoides) is currently under establishment Sweden and it is vital to discover invading individuals to prevent colonization. The use of wildlife cameras to discover dispersing raccoon dogs have been implemented in the north-European raccoon dog management program. In this study, I test the ability of four commercially available scent lures to attract raccoon dogs to camera stations. The study was conducted in the Åland Islands where raccoon dogs are abundant and the results could improve the effectiveness of the camera stations used in the program. I used 12 sites with five camera stations in each and tested the four lures and one control with no lure in each site.

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.

The company is currently in a stage of improvement and has therefore taken the help of students at School of Engineering, Jonkoping University. The current production is batch, production layout is fixed. A bottleneck is created after the first station which leads to large efficiency loss.  The meaning of this report was to provide a layout suggestion with balanced workstations to a new production line. The conditions were that the production line would be one-way, driven by customers order and meet a demand of 40 products per week.

The trend in the transport sector is moving towards eco-friendly, fast and convenient transportation,this results in higher demands on railway transports. To meet the demand and quality requirements,the Swedish railway network will have to expand. The cheapest way is to expand little by little butwhat impact do these small steps actually have on the capacity?This thesis examines the interactions of different improvement for the capacity on a single-trackrailway. Through simulations in the software tool RailSys this report studies what effect block signals,extra meeting stations and rebuilding existing two track passing loops to three track loops have onthe capacity.