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370 Uppsatser om Voltage drop - Sida 1 av 25
Beredning av lokalnät i landsbygd
In this thesis a rural network in Norrbotten, Sweden, has been to designed and planned with the purpose of improving distribution reliability by exchanging existing overhead lines with underground cables. General network design considerations are discussed as well as the ones for the specific low voltage grid. During the design phase the maximum power of domestic consumers has been estimated using Velander?s method. Currents, Voltage drop and impedance of the network have been calculated and fuse operation and selectivity has been considered.
Analys och modellering av ljusbåglängdsregleringen i pulsad MIG/MAG-svetsning
This master thesis deals with problems in the arc length control in Pulsed MIG/MAG Welding. The main problem is that it is not possible to measure the arc length. In the present solution the voltage over both the electrode and the arc represents the arc length. To improve the arc length control a model of the electrode melting has been built. One output from the model is the voltage over the electrode and with this voltage together with the measured voltage it is possible to calculate the voltage over just the arc.
Frekvensreglering i det nordiska kraftsystemet
Svenska Kraftnät is (together with the other transmission system operators of the Nordic power system) responsible for keeping balance between the generated and demanded power in the Nordic power system. Spontaneous load variations and system disturbances, however, lead to power imbalance followed by frequency variations. The frequency deviations can be limited to an acceptable level by the spinning reserve, mainly by hydro power control. But there are also other system properties which have a great influence on the frequency and system stability. The frequency and voltage dependence of the loads have a direct influence on the power balance.
Framtidens elbilar utmanar nutidens elnät : Påverkan av ett ökat antal elbilar på ett halländskt elnät
The challenges facing low voltage grids are rising as an increasing number of domestic houses transition from fossil fueled heating to electricity based heating. Several environmental goals and visions have the same transition from fossil based power to electricity based power in mind for the transportation sector. One of the most important tools for this transformation is widely regarded to be the electric vehicle. With the demands of the electric vehicle pressuring the power grid, several questions arise regarding the growth of the electric vehicle market and what repercussions it may have on the grid. This paper focuses on a typical low voltage grid in southern Sweden and what effects a growing electric vehicle market may have on it. Through computer-assisted simulations based on several future scenarios regarding the EV market, this paper finds that few modifications and reinforcements are needed on this particular grid within the next 10 to 15 years.
Drop in samtal som vägledningsmetod
The point of the study is to investigate educational and vocational counselors' strategies on drop in calls. In order to answer the purpose, the issues concerning the educational and vocational counselors' strategies and guidance models/methods at drop-in calls investigated.Qualitative interviews were conducted with six educational and vocational counselors'.In the study it appears that the educational and vocational counselors' are unable to have any strategies for drop-in conversation because the applicant will come spontaneously and the educational and vocational counselors' lack information about the individual and its purpose of the interview. Guidance models/methods designed to facilitate for the applicant and give them a sense of understanding about them selves there environment and results in a clarification of the election, not often used during the drop-in calls.These are not often used due to the lack of time because the intention of the call is to provide with information to the applicant in as little time as possible. In an educational and vocational counselors? perspective the guidance that is offered at drop-in calls defective..
Voltage Sags Indices and Statistics
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Validering av ett livsmedelsfrekvensformulär för uppskattning av fullkornsintag hos svenska män och kvinnor
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Mat, omsorg och tid : En kvalitativ studie om hemtjänstens syn på matproblem hos äldre
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Corporate Social Responsibility i svenska textilföretag
In Sweden we have the highest rate of nontraditional students among Europe. Coincidently, we also have the highest rates of drop outs among OECD. In this particular field, drop out from higher education, there is a need fore more qualitative studies that can support the "statistics". Studies about experiences of drop outs are significant for society, university and individual. The aim of this study is to describe and understand how nontraditional student experiences drop out from higher education.
Kännedom om och inställning till SAPERE-metoden : En undersökning bland personal på förskolor, låg- och mellanstadieskolor
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Massundanträngning i samband med pålning i lera
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Får barn vara med i köket? : En kvantitativ studie om kommunala livsmedelsinspektörers syn på barns deltagande i kök på förskolor och skolor
To complete an overweight treatment program is associated with better weight loss. Previous studies have in principle focused on drop-out from the entire program, not individual parts of a program. Factors previously shown to influence the patients´ weight loss results are: frequency of individual meetings with a professional, the lack of social support from family or friends, the lack of motivation and in a few studies vacations. In several studies the drop-out patients have stated that their reasons for drop-out were dissatisfaction with the staff and the program design. Drop-out has also been shown to be connected with difficulties in adherence to the diet.
Bestämning av jordmodul för kringfyllnadsmaterial runt rörbroar
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Studie av 3-dimensionella sidoeffekter vid etappvis schaktning i Götatunneln, J2
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.
Utvärdering av trafiklösningar och markanvändning på Södra Älvstranden i Göteborg
Voltage sag indices are a way of quantifying the performance of the power supply, as far as voltage sags are concerned. Indices can be defined for individual events, for individual sites, and for a whole system. A standard method for single-event methods is part of IEC standard 61000-4-30.This thesis emphasizes the importance of voltage sag indices and different methods for calculating three-phase voltage sag characteristics. Three-phase events measured in a medium network voltage over period of one month were analyzed, results examined and statistically evaluated. An algorithm for calculating voltage sag characteristics and indices was created in Matlab.