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10844 Uppsatser om Electric power system - Sida 40 av 723
En jämförelse mellan traditionell och modern taktäckning av industribyggnader
Den här rapporten har som syfte att utreda vilket eldistributionssystem för offshoreenheter som sparar mest vikt och utrymme. De två elsystem som jämförs är GVAs standard system och Siemens Blue Drive System. Rapporten innehåller en teoretisk bakgrund för båda systemen och dimensionering av systemens kraftkablar samt beräkning av kabelvikter och komponentvikten för systemen. För att uppskatta kabel- rutter och längder kommer ritningsunderlag för GVAs offshoreenhet 7500 att användas.Resultatet visar att GVAs standard system är det eldistributionssystem som har den lägsta totalvikten med 168 ton, GVAs standard system har en vikt som är 101 ton lägre än Siemens Blue Drive System som har en vikt på är 269 ton. GVAs standard system har en lägre ström vilket gör att ledararean blir mindre och i med det blir kabelvikten mindre.
De tre vise männen - En fallstudie av Kinas övergångsperiod
When Deng Xiaoping introduced his reform program, he began China's transition from a plan economy to a socialist market economy. Liberal theorists often argue that there is an automatic link between ?free market? and ?democracy?, however this link is not evident in China. This contradiction constitutes the problem area of this thesis.With a theoretical framework containing ?totalitarism? and ?Tang Tsous culturalist approach? I have analysed the leadership of CCP (China's Communist Party) and its strategies to maintain the Chinese political system.
Termisk Vattenpump
This degree project aims at developing a concept for how to use solar energy to pump up water. The target audience is people living in areas where the functioning of the electricity and water network is absent. In these areas, the hand-powered water pump is the most common technology. The degree project's goal is to find an economically viable alternative to the time consuming hand-powered water pumps. The power comes from solar energy.
Förbättrad resistansmätning för grova aluminiumledare
The goal with this master thesis has been to evaluate and to examine the stationary resistance bridge. The resistance bridge uses a 4-point measuring to determinate the resistance, which is used in the manufacturing of the conductor. It is then used when the resistance is to be decided for coarser aluminium conductors. A conductor has to fulfil certain demands to be able to move forward in the process. One of these demands is the resistance in ohm/km, which has demands that the measure values of the resistance bridge are as true and precise as possible.
Framtagning av nytt mätsystem för mätning av energiförbrukning i mikrovågsugnar
The report describes a measuring method for analysis of energy consumption measurement in microwave ovens. Concurrently that the awareness of the environment evolves the demands are growing for more power saving products. This is also counting within the Home Appliance business, which is Whirlpools business area. Whirlpool is therefore interested of launching microwave ovens with documented low power consumption. To be able to implement this, both asserted measuring equipment, that fulfils all demands, and a standard procedure is required.
Dynamisk modellering av VSC-HVDC : En statisk och dynamisk modelldesign o?ver VSC-HVDC fo?r implementering i ARISTO
This thesis treats the subject of a complete steady state and dynamic model of the VSC-HVDC covering both the AC and DC system-side of the converter. The topology of the model is recreated after the scheduled transmission line in the south of Sweden, called SydVa?stla?nken. The topology covers both a simple two terminal connection as well as a multi-terminal one. This model is to be implemented in the power system simulation program ARISTO.
Lastfördelning och effektmätning med Arduino och PLC
Detta arbete var beställt av Sjöfartshögskolan i Kalmar. Skolan ville ha en enhet som kunde mäta aktiv-, reaktiv- och skenbar effekt, ström, spänning, frekvens och cos? på en generator och som kommunicerade vidare dessa värden till en PLC. Detta för att kunna lastfördela lasten mellan ett antal generatorer i kursen Tillämpad elteknik 15 hp där studenterna bygger en generatorinstallation med tre generatorer. Ett funktionsblock för lastfördelning skulle också programmeras.
Kalibrering av en transient GT-Power modell av en SI PFI turbo motor
I detta arbete behandlas transient simulering i ett 1D-simuleringsprogram, i dettafall Gamma technologies GT-Power. Vad som behöver ändras i en modell för attden skall kunna simulera en motor under transienta driftsfall med godnoggrannhet har undersökts. När detta är gjort, skall det undersökas hur väl dentransient kalibrerade modellen kan simulera en motor med förändrad rörgeometripå insugs- eller avgassidan, och vad som måste omkalibreras om detta inte ärfallet.Den viktigaste slutsatsen av detta arbete är vikten av att ha en korrekt framtagenkompressormapp i modellen. Den som fanns tillgänglig under arbetet hade baramätdata ned till 70000 rpm. Detta resulterade i en överskattning av massflödet iden lägre regionen i den av GT-Power framställda kompressormappen.
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.
?Det var en tyst kamp? : En ekokritisk analys om utvandring och fo?ra?nderliga system i Vilhelm Mobergs Utvandrarna
The purpose of this essay is to do an ecocritical reading of Vilhelm Moberg?s The Emi-grants from 1949. By asking and answering the three following questions; How does a system present itself, What are the different reasons for emigration; Why does differentsystem fit some well and some not.By using two articles from Green Planets - Ecology and Science Fiction to illus-trate two different views; Different parts value in an ekosystem and The Ship as an ecosystem. I have also created, based on the literary text four different terms concern-ing the dynamic system; Stable, Static, Unstable and Collapsing systems. I have found that all system goes through changes, some drastic, that changes the way the parts of the systems fit with in it.
Vilka faktorer påverkar börsbolagens nedskrivningsbeslut?
By using univariate analysis, tobit and logit regressions, this thesis investigates determinants of asset writedowns. After controlling for variables indicating reductions in asset values, the results show that changes in senior management are significant in explaining the writedown decision and magnitude, which is in line with previous research. The explanatory power of changes in senior management has not increased with the transition to IFRS in 2005. No evidence is found supporting the hypothesis that the explanatory power of management incentives is higher for more discretionary types of asset writedowns..
Uttorkning av Betong
This Thesis aims to explore how to integrate an IT-system for facilitating anorganizations work with Continous Impprovements.This is done here by examining and analyzing the process within a handful ofcompanies who seem to have been successful with their own implementations. Thestudy is focused on the implementation of one particular system, "System C2".Simliarities and differences between the companies, and the established rule of thumbfor these kind of activities are focused upon. This to emphasis how another actormight emulate some of the apparent success.Part of the core question is found in the title, since Continous Improvement is oftenseen as a relativly low-risk activity, is it then also possible to take a low-risk slow pathto the implementation of such a system in the entire organization?.
Förbättrad resistansmätning för grova aluminiumledare
The goal with this master thesis has been to evaluate and to examine the
stationary resistance bridge. The resistance bridge uses a 4-point measuring to
determinate the resistance, which is used in the manufacturing of the
conductor. It is then used when the resistance is to be decided for coarser
aluminium conductors. A conductor has to fulfil certain demands to be able to
move forward in the process. One of these demands is the resistance in ohm/km,
which has demands that the measure values of the resistance bridge are as true
and precise as possible.
The stationary resistance bridge had been examined through various kinds of
measurements to be able to see how stable the system is and how to obtain a
measure value as optimized as possible.
Utvärdering av fjädrande statorfötter : Nytt koncept i vattenkraftgeneratorer
This thesis is an evaluation of a new design concept for statorfeets in Gallejaur hydro power plant. Founder of the work is Vattenfall AB Vattenkraft. During the 70- and 80´s nuclear power began to be phased in to the Swedish grid, which meant that hydropower became an important source of rules. The generators began running in so called intermittent operations instead of basic operations, which meant 300-600 start/stop per year instead of one-ten numbers start/stop per year. In order to deal with the thermal forces that arise at every start and stop suppliers began to mount so called sliding joints, which is to take advantage of these forces and maintain the stator shape.
En studie om artikelhantering i material- och produktionsstyrningssystem på System Andersson AB
This thesis aims to develop a control system for measuring electromagnetic compability (EMC). This has meant that a controller designed around an ATmega8 microcontroller has been manufactured and programmed. It has also meant the development of a comprehensive control software in the program MATLAB. The control system has been tested with satisfactory results and can now, monitor and control measurements of the EMC-type..