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10764 Uppsatser om Power System Stabilizer - Sida 4 av 718

Modellbaserad drivlinereglering

A cars powertrain consists of everything that is needed for its propulsion. The components in the driveline that transfer the power from the engine to the driven wheels are not absolutely stiff, hence they will wind up due to the torque and act as torsion springs. If you suddenly demand a bigger torque by stepping on the accelerator pedal, a so called tip in manoeuvre, and that torque is acquired from the engine as quickly as possible, the driveline will not be able to transfer that fast torque change due to its weakness and as a result it will start to oscillate. These oscillations will be transferred to the driven wheels and make the car to accelerate jerkily which will be experienced as uncomfortable by the passengers. Furthermore, there is a backlash in the driveline that will make the weakness in the driveline even more excited than it should have been if the backlash did not existed.To avoid too big problems with these oscillations there is a control system that controls the demanded torque.

Energi - och ekonomipotential för solceller i Hållbara Järva

One of the city of Stockholm?s main objectives is to have a society completely free from fossil fuels. To achieve this, several investments regarding improvements in energy efficiency and renewable energy are currently being planned or implemented. One of these investments is a project called Hallbara Jarva which is located in the suburbs of Stockholm. The purpose of this thesis is to examine the prospects of an investment in photovoltaic cells from an energy-saving and economical point of view. The analysis is limited to three buildings within Hallbara Jarva and is intended for the property owner.  Solar energy is a type of renewable energy source and is commonly divided into solar heating and solar power.

Makt i klassrummet : En maktanalys av relationen mellan lärare och elev

This essay is about power in the classroom. It is about the power dimension of the student-teacher relationships that arise in that space. The overall aim has been to investigate which categories are fruitful in a power analysis of these relationships. My aim has therefore been to develop power categories and to use them to identify and to categorise cases of power interaction that take place between those particular actors in that particular setting.In order to gather material for my study I have both read literature that approaches the study of the student-teacher relationships from a power perspective and done a series of observations in a high school.My theoretical frame comprises a concept of power and a series of power categories. These categories include strength, authority, inducement, coercion, violence, resistance as well as to possess power, to have power, to exert power, the scope of power and the base of power.

Distriktssköterskans erfarenhet av interventioner riktat mot att förebygga viktnedgång hos personer med Alzheimers sjukdom : En intervjustudie

The purpose of this thesis is to identify power structures and instruments of power within the Jehovah?s witnesses and investigate how they affect the baptized youths baptized within the organization. The material consists of qualitative in-depth interviews and is analyzed with Foucault's theories of power. The results show that the participants have a very strict relationship to the rules of the congregation and also that they take great care in observing these rules carefully. It becomes evident that young members are exposed to disciplinary measures from the organization.

Hjälpkraftsystem med två lågspänningsnivåer

Because of increasing demand of power on Malmbanan the capacity of the existing wires which supply the trains must be increased. This increases the stress on the existing poles and for this reason the system for supplying the loads along the railway is to be removed from the poles and be replaced by some other system. This thesis is a study on a two-level low voltage (1 kV and 0.4 kV) electrical system with the aim to investigate if it can be an alternative to the system used today taking into account the voltages, fault currents and costs.In this thesis the following tasks have been performed:? Gathering of data? Description of basic theory? Loadow and fault current calculations of the system with MATLAB? Life Cycle Cost estimate of the system? Analysis and conclusions from the resultsThe results show that the new system can be an alternative to replace today's system. The simulations and calculations show that the voltage drop is at an acceptable level and that the fault currents are large enough to supply a safe disconnection if a fault occurs at the far end of the system..

Att Spela Roll - Folkrepubliken Kina som Supermakt

Since the abrupt ending of the Cold Wars the international system of politics has been dominated by the unipolar United States. Leading scholars within structural realism sees this stage as just a temporary condition for various reasons. They also target China as aspirant to embody the role of a balancer against USA and pole in a bi- or multipolar system. Some even argue they are destined for superpower.With the help of realisms definition of power I estimate U.S., China's and India's capabilities and judge their potential superpower. I then go on to connect structural realism and role theory to estimate their different statuses in the system.

Design och tillverkning av en stereoanläggning med aktivt delningsfilter

This thesis is the result of the author?s interest in music and electronics, namely the design and manufacturing of a stereo sound system with an active crossover. In short it can be stated that an active crossover has many advantages over its traditional passive counterpart. The active design naturally results in a more complex system comprised of a multiple number of components. This report deals with the theoretical aspects of preamplifiers, crossovers and power amplifiers as well as power supply and control.

System, stabilitet och makt - informationsdiskursen i Organizing Knowledge

TitleSystems, Stability and Power. The Discourse of Information in Organizing Knowledge.AbstractThe aim of this Master's thesis is to inquire into the consequences of an unequal distribution of power between information discourses in the field of knowledge organisation. A deconstruction of Jennifer Rowley's and John Farrows introductory textbook Organizing Knowledge from 2000 is related to the major discourses of information in LIS. Questions posed in this study are: What meaning is ascribed to information in the material studied? Which information discourses are given a dominant position? Which are excluded? and: How does this affect the construction of the library and information science student's identity, in relation to practices of knowledge organisation? The theoretical framework is provided by Ernesto Laclau's and Chantal Mouffe's theory of discourse and combined with techniques for text analysis originating from the work of Norman Fairclough.The analysis reveals a strong domination of a cognitive discourse of information that underlines the importance of information systems for the organisation of knowledge.

Effekten av höghöjdsvistelse på anaerob arbetsförmåga

Syftet med denna studie var att undersöka om vistelse på hög höjd påverkar den anaeroba arbetsförmågan. Sex aktiva universitetsstudenter, fyra män och två kvinnor, deltog frivilligt i studien. Expeditionen till Nepal varade i 40 dagar och under den perioden sov och vandrade försökspersonerna mellan 1400 och 5100 meter över havet. Före och efter expeditionen genomförde försökspersonerna ett anaerobt wingatetest där peak power, average power, minimum power and power drop uppmättes. Resultatet visade en signifikant sänkning av average power efter den genomförda expeditionen på hög höjd, med ett medelvärde på 8.44 ± 0,84 w/kg före expeditionen och 7.81 ± 0,87 w/kg efter expeditionen.

Åsktransienter och överspänningar : En spänningsfylld simulering av elkraftsystemet vid Forsmark 3

A power system will inevitably be subjected to transient overvoltages, most often produced by switching operations and lightning strikes. These transient overvoltages may harm sensitive equipment without sufficient protection, but it is not an easy task to predict what transients may occur or how they affect the system. A fault occurred in a low voltage system at Forsmark 2012 and overvoltages from lightning were concluded as the probable cause. The three aims with this thesis are to develop and test a model of the power system at Forsmark 3, analyse the transient behaviour of the system when subjected to lightning surges and identify critical parameters, and lastly to provide a tool for investigating the protection of the system. The modelling and simulations were performed in the freely available simulation program LT Spice.

USA som hård, mjuk och smart makt -En studie av amerikansk utrikespolitik i mellanöstern

This essay is built upon the thoughts of Joseph S. Nye concerning power, and the different ways of exercising that power. The characteristics of Nye's theories are the thoughts about the second face of power, or what he describes as the soft power. The essay seeks to examine what kind of power the US has been in their work for non-proliferation and democracy promotion in the Middle East. It also seeks to find what it is that makes the US to choose to exercise the specific powers.

Verksamhetsanalys Jämförelse mellan IAEA och OKG AB inom E.ON-koncernen

The safety and safety work on OKG, Oskarshamns Kraftgrupp, is supervised by SKI, Swedish nuclear power inspectorate. The task of SKI is to inspect that the nuclear power plants of Sweden runs in a safe way. The proprietor of the permit who runs nuclear power plants has the responsibility to maintain the required safety to run a plant. SKI publishes a number of statue books that OKG has to meet to be able to run the plants. SKI recommends in SKIFS 2 004:1, that OKG work with the safety requirements of IAEA.

Visst gör det ont när möten brister : En kvalitativ uppsats om fyra före detta klienters upplevelse av mötet med myndighetsutövare och institutionalisering som behandlingsmetod

The purpose with the essay is to illuminate four former clients? personal stories about the meeting with the authority in the Swedish welfare system and the institutionalization theywent through. The questions being asked in the essay focus on communication, the relationship concerning power and the former clients attitude towards the institutionalization as a treatment. Four interviews were held with former clients who were institutionalized sometime between the ages of 15-25. The results were then analyzed by theories focusing on communication as a way to gain power and how social interaction may influence the individual attitudes towards authorities.

Mätsystem för effektförluster i en högfrekvenstransformator

To measure losses in a transformer with today?s methods is either slow or insecure. There s a new method developed by Alstom that hasn't been actualize in to a test-system and that has been the assignment in this project. The idea is built on a switched system and a CLR- circuit in the resonant frequency. The test-system has a calculated power-loss that make the efficiency to be as high as 99,8% and in reality over 95%.

Wind Power Desalination System

Wind Power desalination for Tunisian markets..

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