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236 Uppsatser om Hydropower stations - Sida 2 av 16

Flödesmätning i vattenkraftverk : Studie av alternativa mätmetoder

Flow measurement is one of the greatest challenges in order to calculate efficiency in hydropower. Most hydropower plants in Sweden use differential pressure methods for flow measurement. These methods are dependent on constant conditions in the waterways. A change in these conditions, like turbine improvements, prevents differential pressure methods to verify efficiency improvements. Since efficiency improvements can?t be verified by one measurement system, another method, which isn?t affected by changing conditions, can be used.

Personalliggaren : Hur har svartarbetet påverkats?

This essay was written at Södertörn University during the spring semester of 2010, in the field of Business Administration, and more precisely within management and organization. The essay is based on a case study of the management of the staff working at the commuter train stations in Stockholm. The study consists of a number of interviews with the management staff and with the personnel working at the stations, where the aim of the study is to describe how management works within ISS Trafficare AB and what the personnel working at the stations think of it. ISS Trafficare AB is the entrepreneur who runs the commuter train stations in Stockholm by an agreement met with Stockholmståg KB.The study is based on information from the interviews with the personnel and other material from ISS Trafficare AB. Research on the area of management have been used to put data into perspective and to further deepen our analysis and conclusions from the case.The essay shows that the management has tried to implement several changes on the organization in order to provide more service to the travelers.

Ledningsarbete på ISS Trafficare AB : En fallstudie av hur pendeltågsstationerna drivs i Stockholm

This essay was written at Södertörn University during the spring semester of 2010, in the field of Business Administration, and more precisely within management and organization. The essay is based on a case study of the management of the staff working at the commuter train stations in Stockholm. The study consists of a number of interviews with the management staff and with the personnel working at the stations, where the aim of the study is to describe how management works within ISS Trafficare AB and what the personnel working at the stations think of it. ISS Trafficare AB is the entrepreneur who runs the commuter train stations in Stockholm by an agreement met with Stockholmståg KB.The study is based on information from the interviews with the personnel and other material from ISS Trafficare AB. Research on the area of management have been used to put data into perspective and to further deepen our analysis and conclusions from the case.The essay shows that the management has tried to implement several changes on the organization in order to provide more service to the travelers.

Analys av monteringslinan för luftbehandlingsaggregat (EC)

The purpose of the work is to analyze and balance an assembly line at Fläkt Woods in Jönköping. The work is going to answer the questions about today?s throughput time, how much waste that occurs, number of staff at the assembly line, how the supply of material works and possible improvements that can be made at the work stations. The work is also going to give a proposal of improve-ments that can be made.The methods used to get the result include observations and measurements, con-versations with technicians and operators and also data from Fläkt Woods? data-base.Large variations in throughput time are measured during the measure period, from 3 hours up to 5 hours and 35 minutes.

Produktionsutveckling av bastuaggregatsavdelning

To invent an optimized product is a complicated process. This process is only half of the work. It is equally important to develop a production system that can produce the product in an  efficient and ergonomic way.After several evaluations of conceptual and detailed drawings a final idea has come to light.The idea intends, to the maximum extent, utilize the facility in a more efficient way through moving assembly lines and stations closer to the flock section and the stock for complete products. To make the production better, stations are placed in more logical places given the assignment they are supposed to accomplish. This improves the material flow radically.

Småskalig vattenkraft :

Small hydropower plants have been an important source for electricity for many years. During the 70?s the general thought was that nuclear was the future. Around 2000 small waterpower plants were shut down. It wasn?t profitable to invest in.

Nedskräpade återvinningsstationer - En studie om fördelning av ansvar

In Sweden, responsibility for the collection and recycling of packaging and newspapers lies with the producers. Therefore, the major producers created a jointcollection with 5800 recycling stations. The stations are the responsibility of a coordinating body, Förpacknings och Tidningsinsamlingen (FTI) which ensures Government regulations are adhered to by the producers.In 2006, the Swedish Environmental Protection Agency (EPA) carried out an evaluation of the collection of packaging and newspapers. EPA´s research showedthat 80 percent of households were satisfied with the collection but that there were also shortcomings, including problems with littering at the recycling stations.We have tried to approach the litter issue from different angles in order to suggestpossible measures to reduce the problem. An important aspect proved to be uncertainties regarding the concept of operators.As there are currently many parties involved in the collection process this lead to the issue of who is legally considered as the operator of the recycling stations.

Migration losses of Atlantic salmon (Salmo salar L.) smolts at a hydropower station area in River Åbyälven, Northern Sweden : passage fates at a reservoir, a power house and a bypass structure

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.

Småskalig vattenkraft vid Olofsfors bruksmuseum : Med faunapassage

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.

Validering av vattenkraftmodeller i ARISTO

This master thesis was made to validate hydropower models of a turbine governor,Kaplan turbine and a Francis turbine in the power system simulator ARISTO atSvenska Kraftnät. The validation was made in three steps. The first step was to makesure the models was implement correctly in the simulator. The second was tocompare the simulation results from the Kaplan turbine model to data from a realhydropower plant. The comparison was made to see how the models could generatesimulation result that was similar to the reference power station.

Bottensedimentets betydelse för flodpärlmusslans föryngring ? en metodutveckling

The freshwater pearl mussel Margaritifera margaritifera is an endangered species. To survive, the young mussels demand a fairly coarse bottom material containing an appropriate quantity of organic substrate to survive without suffocating. In order to estimate if a bottom is suitable for juvenile mussels, samples of the sediment are needed. To obtain samples a sampling device called the Mulv collector has been developed within this project. Bottom samples were collected from 18 stations in 4 south Swedish streams, Vramsån, Kling-storpsbäcken, Brönnestadsån and Bräkneån.

Identifiering av parametrar för tillståndsbedömning av en vattenkraftstation

The report begins with a general inventory of possible technical faults in a hydropower plant and of possible fault indicating measurements. Then an investigation is made concerning a few different faults. Based on this investigation a choice on seal box condition and water leakage is made as problem for a more thorough examination, in which it is concluded that the turbine water leakage is larger when the turbine is put into operation. The examination ultimately results in a computer alarm for faults related to the seal box. Finally a few things are mentioned about flow measurement and pressure measurement in relation to the project as a whole..

Fotogrammetrisk analys av kornstorleksfördelningeni erosionsskydd vid kraftverksdammar

This master thesis was made to investigate the possibilities of using the Matlab-basedsoftware Basegrain to determine grain size distributions of erosion protections onhydropower dams. Basegrain is a photogrammetric tool developed to generate grainsize distributions and other information about coarse flood sediments by analyzing adigital photo of the stone bed. The investigation was made by validating the ability forBasegrain to assess grain size distributions of various materials smaller than the blocksused in an erosion protection by comparing sieving results or manual measurementswith the results obtained by the program. A statistical comparison was then made bycomparing the results from sieving and the program. The possibilities of using thesame method on existing hydropower dams were then investigated by determiningwhether the method was practically viable or not.The results showed that Basegrain generated grain size distributions for coarse gravelthat were very close to the sieving results.

Evaluation of RCM implementation process in Vattenfall
Service and Vattenfall, Hydropower organizations: a study and
analysis of its current status

Vattenfall AB is a large producer of electric energy where approximately half of the energy comes from hydropower. Vattenfall Hydropower has got almost a 100-year old history and the company has developed a lot since 1909. After that the number of power plants increased and the competition got more intense, there were higher demands on the reliability. One way to secure the reliability with a good satisfaction at the power plants is to implement a maintenance method named Reliability-Centred Maintenance. RCM is a result of the introduction of the complex aeroplane Boeing 747 in the 1960?s.

Beteende hos lekvandrande lax i Klarälven ? utvärdering av en fiskfälla

During the migration season in 2013 a study on spawning migrating salmon and the effect of water flow on the behavior was conducted of the salmon at the Forshaga hydropower station in the River Klarälven. The River Klarälven with its nine hydropower plants on the Swedish side, constituting migration obstacles for the migrating salmon. Fortum Generation AB has together with the County Administrative Board restored a salmon trap at the lowermost hydropower station in Forshaga, aiming at making it possible for the salmon to swim into the trap, and thereafter be transported by truck past the power plants and then continue their journey to the spawning grounds on their own. Unfortunately, it is believed that the trap does not work as well as it should. In this study, I focused on salmon position in relation to water flow and if the number of salmon that swam into the fish trap differed between salmon with previous experience of the trap (experienced) and salmon without experience (unexperienced).

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