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233 Uppsatser om Voltage transients - Sida 14 av 16

Konstruktion av datainsamlingskort för mätsystemet COMET

During test flights SAAB uses the data acquisition system COMET 16. The part of the system that receives the signals from the sensors and converts them is called KSM 15. The purpose of this thesis is to develop a data acquisition module on stacked PC/104 modules with a lower production cost. Our work has been divided into one part about analog signal conditioning and a second part with digital filtering and memory management of the sampled data. The analog part, designed of regular components like instrument amplifiers, voltage references, operational amplifiers and multiplexers, adjusts the sensors signal levels for the ADC?s that converts the signals.

Dokumentation av en experimentell biogasanläggning

This thesis is   focused on identifying and documenting all   electrical equipment, such as devices, power lines / cables, and connectors in the facility and also on presenting a brief   technical description and information of the systems around the reactors.   Furthermore there will be a brief description of LabVIEW - which is a   graphical programming language- and which devices / elements   are programmed. For further notification, I am not   responsible for the programming of the devices in LabVIEW   which I have only used as a tool in my work. The plant   for production of biogas consists of four reactors   of which the third reactor (Lakbädden)   is connected to another reactor (UASB)   where they cooperate with each other.   The reactors are used for producing   biogas in the form of methane gas.The reactors I and II are   connected to, various electrical devices as, flow meters, temperature   sensors, frequency converter and   more.

Analys av mellanspänningsnätet i centrala delar av Västerås stad

The dependency of continuous electricity supply is high in the Swedish society today, at the same time no one is willing to pay for a too costly or over dimensioned power distribution system. The owners of the distribution systems are the ones responsible for this balance act of maintaining a high quality of electricity delivery to customers at a reasonable cost.In this master thesis a limited part of the primary distribution system (10 kV), owned by Mälarenergi Elnät AB and located in the city centre of Västerås, was chosen for a deeper analysis of its reliability. Its ability to handle outages of system components (N-1 and N-2 contingency analysis) was investigated to find out potential weak spots and parts of the grid that showed signs of being overdimensioned.The results of the performed simulations showed that in 74 % of the studied N-1 contingencies cases, consisting of outages of a bus bar in a distribution substation, the system could handle this without causing outages in other parts of the grid. For the N-2 contingencies 61 % passed the test. It was also found that one of the two included high voltage substations could alone supply the investigated part of the grid.

Avbrottsfri Kraft med användning av ultrakondensatorer

The supply of uninterruptible power can be applied to many areas wherecontinuous operation is highly prioritized.The application of uninterruptible power for motor operation is facilitatedusing a frequency converter. Direct current operated frequency converters canbe applied directly to the power reserve which removes the need for additionalpower-converting.Batteries have long constituted the power reserve but advancements inthe development of ultracapacitors have created a viable substitution. Ultra-capacitors have high energy storing capabilities and can be applied to highpower applications.Maxwell is a leading manufacturing company of ultracapacitors and pro-vide different modules with built-in solutions for voltage balancing. Unevenvoltages between series-connected capacitors is a phenomenon caused by vary-ing capacitance. A configuration containing Maxwell?s 56V module is createdand constitutes the power reserve in the simulations.The discharge simulation shows a significant current that could damagethe system.

Säkerhetsanalys av brandbekämpning i kritiska utrymmen på Forsmark 1

In order to maintain a high safety level at a nuclear power plant it is important not only to measure the reliability of the components and systems of the plant, but also to investigate how the plant responds to human actions. One of the most hazardous situations in managing a power plant is fire occurring in critical areas. This study concerns the prospect of the local fire brigade to suppress a fire that has started in one of the most critical rooms for maintaining high reactor safety. The model created gives an indication on the possibilities of succeeding in suppressing a fire. In order to get a more reliable fire fighting the following advice are given:- Let the fire brigade go rounds in the plant together with the personnel, during which recommended fire suppressing methods are determined to avoid long preparation time in an actual situation.- Prepare rooms with two subsystems to make them partly with no voltage.- Give the fire brigade better feedback from actual events on nuclear power plants.- Education and training in suppressing fires in electrical equipment.The probabilistic safety assessment strives to be as realistic as possible.

PSQS ? Power Supply Quality Simulator

Kitron had wishes to be able to test and measure how disturbance affects their vehicle electronic units before they have been verified by SP Technical Research Institute of Sweden in Borås. This work started with the writing of a demand specification together with Kitron for a product PSQS, Power Supply Quality Simulator, which can generate some test pulses according to a standard for electronic units to Volvos vehicles. A design proposal was developed with the help the demand specification and was verified with the help of simulations. All electric schematics was designed with the guide of the design proposal. The pulses realized in the works of this thesis are those which Kitron experienced that they have a need to test in their own premises and which are possible to generate with the means available.

Spänningsfall i 200 V 400 Hz system

Målet med examensarbetet har varit att ta fram teoretiskt underlag och en beräkningsmodell. Detta ska beskriva hur kabeltyp, kabellängd, kabelarea samt effektfaktor påverkar spänningsfallet över ett 400 Hz ledningssystem.Mätningar har utförts på två olika kablar som används i det aktuella systemet. En av kablarna var symm­et­riskt uppbyggd med 7 ledare, där respektive fas bestod av två ledare förskjutna 180° från varandra runt nolledaren. För att åstadkomma 115/200V 400 Hz, användes en 90 kVA frekvensomformare. Belastningen som användes var en resistiv, induktiv samt en kapacitiv belastning.

Numerisk simulering av jordtryck mot rörbro ? Med tillämpning av programmet PLAXIS

This thesis deals with numerical simulation of earth pressure against tubular bridges in the software Plaxis. Plaxis is a FEM (Finite Element Method) software based on numerical calculations for which approximate solutions are developed through an iterative process. The program is specifically designed for soil and rock mechanical tests, such as voltage and deformation calculations in soil.The Royal Institute of Technology conducted in 2005, field tests on tubular bridges of corrugated steel, which was part of Ersa Bayoglu Fleners PhD (Bayoglu Flener, 2009). She studied how two different tubular bridges deformed during installation and filling. Tests and measurements were made during filling.

RCC-Jordfelsskydd, mätmodul för övertonsanalys

The majority of all power cuts that affects individuals and communities are caused by earth faults on the power transmission lines at 10kV and 20kV level [1]. If these power cuts could be eliminated, less disturbances and interrupts would lead to large amounts of money savings.Swedish Neutral has developed such a protection system. When an earth fault occurs power is injected into the neutral point of the transformer. The RCC (Residual Current Compensation) protection calculates a compensation current exactly 180 degrees out of phase to the fault current. Doing this, the voltage at the fault location becomes very close to zero, without affecting the power transmission.The protection system can only compensate automatically for the fundamental frequency (50Hz), and manually for the 3rd, 5th, 7th and 9th harmonics.

Elektronisk motorstyrning för ottomotorer

The combustion engines in today?s vehicles are getting more and more advanced and there are increasing demands on that the engines should operate during optimal conditions. Examples of internal combustion engine parameters which may be carefully controlled are the rate between fuel and air, that this gas mixture is homogenous enough and that it is ignited at the correct moment. Moreover, the requirements of these parameters vary depending on, among other, engine speed and load. To meet these requirements in all occurring operation conditions, it is required that many subsystems work together.

Klimatkabinett : Komponenter och konstruktion

This report describes the construction of a climate-cabinet for testing of HV-cards (High Voltage) produced at VG Scienta. The main part of the report describes all the different components of the cabinet. The most important parts are a PID regulator from Eurotherm model 2408, a solid state contactor (SSC), a thermocouple, a finned resistor from DBK and different fans. The report even includes the connection between components by cable wiring, isolation, grounding, fuses and shaping of metal goods.As the cabinet also communicates with a computer, the report includes the solution of the data communication using the software iTools from Eurotherm. The communication part includes information about a converter that converts EIA422 to USB.The cabinet was produced at a company, called VG Scienta, in Uppsala during the spring 2010.

Utveckling av väggenomföringar av typen RIP

Examensarbetet har genomförts på ABB Components i Ludvika. ABB Components är en affärsenhet inom ABB-koncernen som tillverkar nyckelkomponenter till transformatorer, bland annat genomföringar som kan ses som en isolerande hylsa vars uppgift är att föra högspänd ström genom jordade plan.Examensarbetets syfte är att utföra en förstudie som sedan ska fungera som underlag för ABB Components utvecklingsarbete vad gäller genomföringar av typen RIP (Resin Impregnated Paper). Bakgrunden till förstudien är ökade miljökrav världen över vilket innebär en marknad där miljöfrågor får allt större inverkan. Följden av marknadens utveckling är att ABB Components har insett att de har ett glapp i produktportföljen vad gäller genomföringar av typen RIP.För att skapa det underlag som är nödvändigt för att nå målet med förstudien har metoder som intervjuer, observationer och sökningar i databaser tillämpats. Målet med förstudien har sedan uppnåtts genom att generera lösningskoncept i form av CAD-modeller.

Framtidens driftcentral : En analys av den framtida driften av ett svenskt elna?t

Active work to increase the efficiency of energy use is taking place in Sweden and throughout all of Europe. Electricity is an important part in our society?s energy system which means that the electrical grid operators and associated therewith has a central role in this work. Monitoring and controlling the electrical grids are managed from the distribution system operator?s DC, dispatch center.The aim of this report is to examine how the operations in a typical DC on the Swedish electricity distribution network will look like in five to ten years.

Standardisering av bakpanel.

HAFA Bathroom Group has given us the assignment to develop a standardized back panel for their bathroom cabinets. This cabinet is going to be applied to most of their current and future cabinet solutions. To this point, they have constructed unique suspensions-and back panels for most of their cabinet models. They have also been forced to pull wiring and assemble the cabinets differently because of factors like; position of the wall sockets, dimensions of the cabinets and their shapes.The company wants to distance themselves from their current solution, firstly because the cost of having manpower to design each individual suspension solution, secondly because they will save a lot of money when the manufacturing process requires a minimum of components to be constructed. As a result of this, the company can use their resources better to develop future products.The main idea is that the consumer isn?t required to change the suspension or back panel when they decide to buy a new cabinet.

Solcellsdrivning av distribuerade inbyggda system

The high level of energy consumption that the industrialised countries have reached and thepollution that this brings has long been a cause for analysis and debate, development and usageof so called renewable energy sources is therefore more important than ever. The energy in theelectromagnetic radiation from the sun is an interesting alternative. One way of harvesting thisenergy is by using solar cells, devices that generate DC current when exposed to electromagneticradiation.The goal of this master?s thesis was to design a solar powered power supply to Syntronic AB?sMidrange platform. The envisioned application is a stand-alone distributed embedded system,for example a node-based temperature monitoring system.

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