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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Automation of refilling station in clean room

Sollie, Vincent, Malmström, Johannes January 2019 (has links)
This thesis aims to confirm a proof of concept on how to get a robot to pick up a plastic bag containing 3500 plastic caps, cut it open and pour the content, all within a restricted Clean room. The work was executed in an agile way with several ongoing iterative processes in parallel. In the present production line, refilling caps are done manually. For those working in the production line, this task entails heavy lifting and the concern of keeping an eye out for when to refill and how many caps there are in the production line all the time. The result is a working prototype of a robot tool, consisting of a combined clamp and vaccum bag gripper and a self standing linear unit with a blade mounted to it. When tested, this proved to be a functioning solution to the task in hand. The gripper is designed to be mounted on a six axis industrial robot and the blade is placed inside a robot cell. Simulations show that the task is easily done fast enough to supply 5 production lines, producing in full speed,with caps. Solely this unit will not contribute much to a production line if implemented in a factory, since it does not take material flow into consideration. It can merely be seen as a part of a bigger automation chain.
12

Savonius wind turbine innovation integrated in a constructed nano grid system

Andersson, Oskar January 2019 (has links)
A nanogrid system for supplying neutrino detectors on Antarctica with electricity is designed and built. The nanogrid system could later on be implemented in various configurations where suppling electricity to neutrino detectors is one area of use. The energy system that is acting on site in Antarctica is based around solar panels to provide power to the measuring equipment. However, providing electricity in such a way is not optimal due to its failure in delivering electricity at times. A nanogrid that can stand the demands of constant energy supply to the measurement station are therefore constructed. The energy sources that are integrated into the nanogrid are an innovation in vertical axis wind turbine and photovoltaics. The wind turbine innovation is tested under real conditions for the first time. In the constructed nanogrid, there are also integrated energy storage consisting of battery cells that are coupled together to a coherent unit. Measurement equipment is also implemented for analyzation of acting wind turbine as well as different types of safety equipment for redundancy in the system. In the nanogrid, a rectifier for AC to DC transformation is constructed. An inverter for DC to AC transformation is also implemented for supplying electricity to the equipment that are acting on the grid. The system is tested under real conditions. The whole system could observe partially function and configurated well to the various parts of the whole system. Further optimisation of some parts of the system from the prototype is needed.
13

Projektering av lokalnät med fördjupning i selektivitet

Ebers, Lucas, Eriksson, Niklas January 2019 (has links)
In power system, when a local network with over head lines is replaced by a network laid underground, itchanges the characteristics of the material used and gives an opportunity for an updated sizing. The goal withthe project was to present a proposal of a reconstruction of a old local network to a modern local network andpresent a selective coordination plan for all the branches in the new network. The methods that are used isthe Velanders method for interleaver of the maximum power, sizing according to “SvenskStandard”(Swedish Standards) and curve fit of trip curves to present digital produced selective coordinationplan. The new underground local network delivers a better electrical quality, that fulfills the triggerconditions and obtains a good selective coordination. / Inom elkraftsystem, när ett luftburet lokalnät ersätts med ett markförlagt förändras förutsättningarna i formav materialets egenskaper och det ger möjlighet för uppdaterad dimensionering. Målet var att presentera ettförslag på ombyggnation av ett äldre luftburet till ett modernare markförlagt lokalnät och presenteraselektivplaner för samtliga grenar av det nya nätet. Metoder som använts är Velanders metod försammanlagring av maxeffekter, dimensionering enligt Svensk Standard och kurvanpassning avutlösningskurvor för att presentera digitalt framställda selektivplaner. Det markförlagda lokalnätet levereraren bättre elkvalitet, uppfyller utlösningsvillkoret och erhåller god selektivitet.
14

SOLENERGI FÖR JORDBRUKSNÄRINGAR : Ekonomiska förutsättningar för jordbruksnäringar för installation av solcellsanläggningar

Jansson, Hampus January 2019 (has links)
The purpose of this project is to analyze the economic parameters that affects the profits from a roof mounted solar cell installation for an agriculture company in Sweden. To analyze the different production type and the impact of the fraction self- used electricity is calculated with respect to the direction of the installation. The parameters that are affecting the profit are the yearly electricity production, the investment cost, the fraction self-used, the price of bought and sold electricity and any subsidies. The conclusion is that the type of production does not affect the self use as much and an installation facing south still have a higher self use due to the higher total electricity production. The most important factor for profit is the subsides, without subsidies the investment does not give a positive yield rate. In second place comes the orientation and the total investment cost. Two of the three companies studied would get 1-3% inflation compensated interest rate with 20% subsidies and the third, relatively located far up north, reached 1-2% inflation compensated interest rate with the same subsides. The lower interest rate comes from the lower yearly electricity production. Another 2 percentage interest rate can be added if the subsides of 40% is granted for all three of the studied companies. As complement to the already existent feeder cable a solar plant combined with a battery storage can support a new house on the property during summer. As a backup for a power outage, a solar plant and a battery costs more and does less than a tractor driven electric generator.
15

KONCEPTANALYS OCH DRIFTFALLSOPTIMERING AV "FREEPOWER – SOLAR BOAT" / CONCEPT ANALYSIS AND OPERATION CASE OPTIMIZATION OF "FREEPOWER - SOLAR BOAT"

Ahlbäck, David January 2019 (has links)
This report aims to analyse the concept of Bjurtech AB:s ongoing development project “Freepower - Solar Boat”. Main focuses are technical optimization and usability from an end user perspective. Bjurtechs idea is to build an electric-powered 5-meter boat charged by integrated photovoltaic cells. The project´s intended pilot market is Sri Lankas coastal fishing fleet. A version for the Scandinavian market is also under consideration and both concepts are analysed in this report. Initially a 4.5-meter prototype was built and tested to try the concept in practise. Methods used are computer simulations in Matlab based on data collected from trail runs with the prototype combined with weather data from Sri Lanka and Sweden. The data and simulations were then used to try to determine whether the concept works for the intended target markets, as well as how the assumed user profiles affect usability and technical deterioration such as battery life. The approach used was to try to determine how to maximize the availability of the system in regards to battery charge level over the whole year at the same time as maximizing distance and boat speed per day. The systems CO2 emissions were then compared to an equivalent petrol-powered boat with the same amount of running hours over 25 years. The main findings of the study are, provided 12 to 14.5 nautical miles is regarded as a sufficient daily distance at 3 to 3.7 knots boat speed, that the system can deliver a high level of availability all year around for fishing operations in Sri Lanka. Considering the demand for daily availability is not as high for the assumed recreational use in Scandinavian markets the system is deemed to perform at a satisfactory level at these latitudes as well. The CO2 comparison showed a significant emissions decrease in the case of year around operations in Sri Lanka. In Scandinavia a reduction is obtained if there are a sufficient amount of operating hours per year. An increase of the installed rated power, Wp, was found to be the most cost efficient way of improving overall performance and that the prototypes photovoltaics of 580 Wp should in both the Sri Lankan and Scandinavian case be increased to a minimum of 800 Wp. Finally it was concluded that user awareness of how system operation impacts battery life can be of significant importance for a positive environmental result and long technical lifetime.
16

Trådlös multimeter för smarta terminaler

Nordmark, Viktor, Kolmodin, Tobias January 2014 (has links)
No description available.
17

Internet of Micropumps : A secure IoT implementation of micropumps

Joel, Öhrling January 2017 (has links)
The Internet of Things is a hot topic for development and research right now.More and more devices get connected to Internet by the day, but sometimesthe security of Internet of Things is neglected. Xavitech is a manufacturer ofmicropump that is interested in entering the world of the Internet of Things.This thesis work was done in collaboration with Xavitech and aimed to look athow an Internet of Things implementation for micropump could be designedin a secure manner. The goal was to design a concept application that could beused to calibrate micropumps remotely over the Internet, with primary focuson the security of the in-flight data of the application. When designing thisconcept application, an existing reference model was used as a basis. Acomparison of different protocols suitability for this application was alsoconducted and the most suitable protocol was implemented. The conceptapplication proposed in this thesis is an example of how a secure Internet ofThings implementation for micropumps can be designed.
18

SOLENERGI FÖR MILLENNIUM AVSALTNINGSANLÄGGNING : Undersökning av potentialen hos solceller i en off-grid lösning som energikälla inom projektet ''Water in a box''

Wu, Ming January 2018 (has links)
This thesis aims first to investigate whether solar panels on the container can provide the process of desalination with energy at the desired location, as well as to dimension a photovoltaic system and battery storage that can run the facility off-grid. Then investigate whether solar cells can be an effective energy solution for Millennium Desalination Device (MDD). The results of this study show that the most annual solar production from containers is 11 510 kWh in Gobabeb, Namibia with a modular efficiency of 22,8 %, which corresponds to 8,2 % operating time per year and is the longest operating time that can be obtained from the all three scenarios. This means that with existing technology and only solar panels on the container, desalination plant is impossible to drive all year round off-grid. The installed power for driving 100 % operating time for one year is 141 kW in Gobabeb and 179 kW in Visby, the corresponding module surface will be lowest 618 m2 and 1184 m2 with modular efficiency of 22,8 %, but there are no additional spaces for all equipment like MDD, solar cells and battery in the container. If the operating time drops to 50 %, the installed power will be 71 kW in Gobabeb, the corresponding module surface will be lowest 415 m2 and battery storage capacity will be at least 160 kWh. Net volume with all equipment will be less than the volume of the container. The cost will be at least 0.2 Swedish kronor per liter of pure water produced with a life of 25 year for solar modules. Usage fee per liter of delivered water is 0.03 Swedish kronor in Gotland and it means MDD is not a cost-effective solution for Gotland at nowadays. But costs may fall in the future with the price reduction of solar cells and batteries. For water shortage areas, this can be a valuable way to solve the water crisis, but it also depends mostly on the area’s water price.
19

Impact of Renewable Energy Installations and Utilisation of Smart Energy Management Systems on low-voltage networks- a study case at Östergarnslandet, Gotland

Sudhakaran, Sujith January 2019 (has links)
This thesis carries out an analysis of PV panel installations in the region of Östergarnslandet, situated in the Swedish island of Gotland. A low-voltage grid of 0.4 kV in the region is examined with the help of software Open DSS. This is done with the data provided by the distribution grid owner, Gotlands Elnät AB (GEAB). The potential impacts created by the PV installations in terms of exceeding currents, voltages and harmonics are assessed and thereby the hosting capacity of Solar PV in the houses and on the whole grid is studied.   Moreover, a theoretical review of the Smart Energy Management System (SEMS) is investigated about the performance and the devices involved in the system. Also, a battery which is a part of SEMS is modelled, taking into account the production and consumption of a single household connected in the grid. The battery sizes for various PV installations at the home is suggested via NPV analysis with the intention to increase the self-consumption and to reduce the cost of the electricity bill. In addition, a survey is conducted in the region with support from the Department of Earth Sciences, Uppsala University Campus Gotland. The survey is made to determine the attitude of the people in Östergarnslandet towards an energy transition. The results show that the maximum amount that can be installed or the hosting capacity of solar in the studied grid is 120 kW. From the simulations, it shows that the impacts created by these PV installations do not violate the specified Grid norms. From the theoretical analysis, SEMS is found to be a better solution for energy management at homes. The performance study done shows that 33 % of the solar energy produced in the home is directly used at the time of production. The remaining energy is used for battery charging for the future supply of power and feeding to the grid. The battery modelled for 10- kW PV installation in the home is found to be 9-kWh and the same for a 15-kW installation. Meanwhile, for a 20- kW installation, a 15-kWh battery is found to be ideal from the study. The survey conducted in the region has turned out to be positive as people are supportive of the energy transition. The responders have marked photovoltaics as the prime option for investment in energy production which assures that it has a good future in the area.
20

Over voltage protection device for ROV

Kantzon, David, Lahti, Sebastian January 2014 (has links)
Supplying power to equipment always imposes a risk of damaging it. This risk is apparent in every application whether it be an industrial or a home appliance. One of these harmful occurrences is something like lightning which introduces a potentially harmful voltage in the system. To reduce the risk of damage significantly an over-voltage protection device is needed. Devices which deal with this problem are common in any electrical equipment and this report deals with the construction and evaluation of one such unit. The device or equipment needing protection in this case is an industrial underwater robot built by Ocean Robotics. In order for this robot to operate safely it needs several protective measures where an over-voltage protection system is one of them. This system provides protection against over-voltages appearing on the main cable supplying the robot, where the input voltage ranges from 200 to 600 volts. As the desired voltage output range from the over-voltage system is 250 to 350 volts it must be able to handle significant power in some cases. Due to the restrictions on functionality given by the contractor a novel way of achieving the goals was tested. The completed prototype can only dissipate 70 watts of power which is far from the required 1500 watts which was specified in the sheet of requirements. However, this system could be used to protect equipment with lower requirements for power handling capability and with added time and effort it could possibly meet the requirements for this project as well.

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