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671 Uppsatser om Relay protection - Sida 1 av 45

Framtagning av reläskyddsinställningar för en transformatorstation

A substation must be properly protected against lightning and other external effects to the equipment in the station or staff, for that we use Relay protection. They should also protect against internal errors which may occur as ground faults. There are different types of protection relays, but most common are overcurrent-, distance-, residual current- and differential protection.The purpose of this thesis was to deepen our knowledge of Relay protection and to use the theoretical knowledge we got from the university studies in the work process. In the process we discovered which parameters were the most essential and calculated these for all Relay protections on the substation. We also carry out a comparison between two brands of Relay protection, ABB and Alstom.During our work we will test and simulate the over-current relays in a program called NEPLAN, the program will also calculate the fault currents.

Quartzene i gips : Densitet och hållfasthet

A substation must be properly protected against lightning and other external effects to the equipment in the station or staff, for that we use Relay protection. They should also protect against internal errors which may occur as ground faults. There are different types of protection relays, but most common are overcurrent-, distance-, residual current- and differential protection.The purpose of this thesis was to deepen our knowledge of Relay protection and to use the theoretical knowledge we got from the university studies in the work process. In the process we discovered which parameters were the most essential and calculated these for all Relay protections on the substation. We also carry out a comparison between two brands of Relay protection, ABB and Alstom.During our work we will test and simulate the over-current relays in a program called NEPLAN, the program will also calculate the fault currents.

Base stations for communication in obstructed environments

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..

Excel-baserad beräkning och dokumentation av distansskyddsinställningar

This is a master thesis work carried out at the Department of Energy and Environment atthe Division of Electric Power Engineering. The master thesis work describes the theoryof distance protection relaying in 130 kV meshed distribution networks. The main aim ofthe thesis was to construct an Excel application for calculation and documentation of thesettings for distance protection relays. The program is based on general methods forcalculating settings of the different zones for the distance relay and presents the settingsin simple graphics using quadrilateral characteristics.The reason for building an Excel based application is the great variety of distanceprotection relays in live networks. The manufacturers of distance protection relays makeprogram for documentation available, however, they are based on the typical settings forthe specific relays.

Halvledare för höga strömmar i fordon

Mechanical relays are more and more being replaced with semiconductortechnology. In this thesis it is investigated if and how the larger loads couldbe controlled by transistors. The main part of this work aims to create andverify a solution that can control the starter motor, as well as protect it incase of any failure. The different malfunctions that the solution protectsagainst is high current, too high peak current, low current, maximum cranktime and minimum cool off time. The timers also protect indirectly againstoverheating of the starter engine.The transistors used are BTS555, from Infineon.

Översyn av vattenskyddsföreskrifter med tillhörande vattenskyddsområde i Hallstahammars kommun. : Vilka revideringsbehov finns?

Water is an important food and an important natural resource. In order to protect these are the Environmental Code and the EU directive given to water protection and related water protection regulations will be established for all water sources until 2010. Those who will prepare a water protection and related water protection regulations is the municipality or person responsible for water supply. The person then decides and declares the area as water protection and related water protection regulations are municipal or provincial government. The idea of creating a water protection is to protect the water supply and the body of water against pollution caused by point sources, diffuse sources and accidents combined.

En ändamålsprövning av kapitalskyddsreglerna i nya aktiebolagslagen : En jämförelse med norsk och amerikansk rätt

This thesis discusses the validity of the Capital Protection Rules under the new Companies Act.The areas of particular interest and cause for debate focus on the advantages and disadvantages for creditors under the laws regarding minimum capital requirements, capital distributions, stock acquisitions, stock minimization, loan restrictions and forced liquidation.How could creditors receive better protection?What changes would have to be made to the Capital Protection Rules to provide better protection and what would be the consequences of these changes to the shareholders, the government and the creditors.Could or should we model the Norwegian or American Judicial system in this situation?Included is an in depth report on the Swedish Capital Protection Rules outlining what they are, what they entail and what the reasoning was behind them. Also included are the EU equivalents and Norwegian and American Capital Protection Rules..

Ytterväggar och bjälklag för flerbostadshus

The thesis demonstrates protection solutions that can be suitable for a camp during internationalmissions in order to resist complex threats. The threats could consist of small arms, machineguns,RPG 7, anti armour missiles, mortar, artillery, HPM-weapons, car bombs, biological and chemicalweapons as well as sabotage and theft. It?s not the technology itself that makes the threat scenariocomplex it?s the way the opponent acts during the operations. The opponent acts usually incivilian clothes and therefore he is difficult to distinguish from other civilians.

Byggserverövervakning : Utveckling av ett system för att synliggöra integrationsproblem

Mjukvara i datorer styr många viktiga funktioner i dagens samhälle och används i stor utsträckning för att kommunicera men även för att styra utrustning. För att mjukvara ska fungera tillförlitligt behöver den byggas korrekt och testas utförligt. För att uppnå tillförlitlighet kan en byggserver används för att automatiskt bygga och testa mjukvaran. Den här rapporten beskriver hur en prototyp av ett övervakningssystem för byggservrar skapats. Systemet sköter övervakningen genom en övervakningstjänst som hämtar information från en byggserver av typen CruiseControl.NET [10] och presenterar informationen på en webbportal.

Skyddet av en camp vid internationella insatser mot komplexa hot

The thesis demonstrates protection solutions that can be suitable for a camp during internationalmissions in order to resist complex threats. The threats could consist of small arms, machineguns,RPG 7, anti armour missiles, mortar, artillery, HPM-weapons, car bombs, biological and chemicalweapons as well as sabotage and theft. It?s not the technology itself that makes the threat scenariocomplex it?s the way the opponent acts during the operations. The opponent acts usually incivilian clothes and therefore he is difficult to distinguish from other civilians.

Graviditet och föräldraledighet : En uppsats om föräldrars skydd mot diskriminering i arbetslivet

Sweden adopted a new anti-discrimination legislation 2009, DiskL, which aim to prevent direct and indirect discrimination in matters of employment and occupation.According to directives and practices from EU, pregnant workers are entitled a special protection from discrimination during employment situations. The purpose of this essay is to study the legal protection for pregnant workers in employment situations and also analyze whether male workers have similar protection when they plan parental leave. Both regulations from the EU-law and the Swedish law are presented and discussed. This because Swedish discrimination legislation is largely influenced by the EU-law.The study confirms that pregnant workers have a strong legal protection against discrimination through directives from the EU and DiskL. Employers must include this protection in employment situations.

Att göra affärer i Kina - rättsligt skydd i lagen och i verkligheten

This thesis looks at the difference between the legal protection in law and the legal protection in reality when a small company working with international trade comes in contact with seller's breach of contract. The thesis uses a case taken from a company with over 30 years experience trading with China and looks at the legal protection available along with the different possibilities of dispute resolution available to a company and then looks at the reasons why this legal protection never becomes a reality and the thesis also analyses some possible reasons for this gap between law in the books and law in reality..

Obstinat och rabiat eller lat och flat? : En diskursanalys av medias framställning av socialtjänsten.

The aim of this essay was to deepen the knowledge of how child-protection-work is illustrated by massmedia. The essay takes it stand in discourse analysis to explain what image is displayed of social work concerning child-protection that is published in news media during 2007 in one of Sweden?s most read evening-papers. The result of the study is that social workers involved in child-protection-work often are categorized as either too zealous or too uncommitted, in the media. The result reflected the current discourse concerning how social workers do their duties in the modern society..

Brandskydd av stålkonstruktioner : Lathund för brandskyddsdimensionering av stålprofiler

This bachelor thesis covers fire protection methods of structural steel and the aim is to develop an information tool designed for inexperienced structural engineers. The information tool covers basic fire protection methods and the general way to produce a fire resistance for structural steel. The layout of this information tool is a simple folder that contains information about the most important steps when producing fire protection for a steel structure.The thesis starts with a general overview of the fire protection needed in buildings to fulfill national legislative and regulatory requirements. To get an understanding of how steel components behave during the influence of fire, a brief overview is presented of the material properties of steel. This chapter also contains a review of previous research in the area.

Systematiskt brandskyddsarbete med Hallsta pappersbruk som tillämpningsexempel

The aim of this report is to improve the fire safety at Hallsta Paper Mill in Hallstavik, Sweden. In order to do so large parts of a fire-protection management system for the paper mill has been created. The report begins with giving a general description of management structures and fire-protection management systems. An account is given for how management structures are designed, and how they should be implemented, maintained and updated. Thereafter follows a description of what routines and instructions should be included in a fire-protection management system..

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