Change search
Refine search result
123 101 - 145 of 145
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Rows per page
  • 5
  • 10
  • 20
  • 50
  • 100
  • 250
Sort
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
  • Standard (Relevance)
  • Author A-Ö
  • Author Ö-A
  • Title A-Ö
  • Title Ö-A
  • Publication type A-Ö
  • Publication type Ö-A
  • Issued (Oldest first)
  • Issued (Newest first)
  • Created (Oldest first)
  • Created (Newest first)
  • Last updated (Oldest first)
  • Last updated (Newest first)
  • Disputation date (earliest first)
  • Disputation date (latest first)
Select
The maximal number of hits you can export is 250. When you want to export more records please use the Create feeds function.
  • 101.
    Owe, Pernilla
    KTH, Superseded Departments, Electric Power Systems.
    studie av överförningskapacitet med hjälp av faktoranalysmetoden1995Independent thesis Advanced level (professional degree), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    missing

  • 102.
    Perdana, Abram
    KTH, Superseded Departments, Electric Power Systems.
    Dynamisk modellering av vindkraftverk med dubbelmatad asynkronmaskin2002Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 103.
    Persson, Jonas
    et al.
    KTH, Superseded Departments, Electric Power Systems.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Linear analysis of a two-area system including a linear model of a thyristor-controlled series capacitor2001In: 2001 IEEE Porto Power Tech Proceedings, 2001, Vol. 2Conference paper (Refereed)
    Abstract [en]

    This paper describes a method to construct a linear model of a thyristor-controlled series capacitor (TCSC) by analyzing its response in a time domain simulation wherein the TCSC is represented by a detailed instantaneous value model. To create the linear model Matlab’s System Identification ToolBox is used. The linear model in the classic ABCD-form is included in both time simulations and linear analysis of the power system. With this technique, dynamic behavior of the TCSC are included in linear analysis of the power system. The studied power system is a simplified model of the TCSC compensated south-north link in Brazil. Comparisons between the linear and the instantaneous value model of the TCSC are performed. By using the linear model, simulations can be done much faster (the computing time is reduced) and still includes the dominant behavior of the TCSC.

  • 104.
    Persson, Mats
    KTH, Superseded Departments, Electric Power Systems.
    Lastprognostisering på en avreglerad elmarknad1998Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 105.
    Phang, William
    KTH, Superseded Departments, Electric Power Systems.
    En modell för det europeiska kraftsystemet1996Independent thesis Advanced level (professional degree), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    Missing

  • 106.
    Poza Sanchez, Elena
    KTH, Superseded Departments, Electric Power Systems.
    Centraliserad eller distribuerad kraftproduktion: en jämförande systemanalys2000Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 107.
    Quaranta, Gianluca
    KTH, Superseded Departments, Electric Power Systems.
    Modell för simulelring av den nordiska elmarknaden2002Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 108.
    Rendelius, Jonas
    KTH, Superseded Departments, Electric Power Systems.
    Tvåstationsekvivalent av vattenkraftsystem2004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 109.
    Roset, Philippe
    KTH, Superseded Departments, Electric Power Systems.
    Belastningfördelning för tillförlitlighetsberäkningar i RADPOW2000Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 110.
    Rådman, Anna
    KTH, Superseded Departments, Electric Power Systems.
    tillämpning av modalanalys för studie av transient stabilitet2001Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 111.
    Sabbagh, Habib
    KTH, Superseded Departments, Electric Power Systems.
    Prisprognos för reglermarknaden2004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 112.
    Sandberg, Åsa
    KTH, Superseded Departments, Electric Power Systems.
    Inverkan av fördröjningar i styrsignaler på transient stabilitet1998Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 113.
    Schönborg, Niclas
    KTH, Superseded Departments, Electric Power Systems.
    Low frequency electromagnetic theory for twisted configurations1998Licentiate thesis, monograph (Other scientific)
  • 114.
    Silfwerbrand, Carl-Johan
    KTH, Superseded Departments, Electric Power Systems.
    Unified Power Flow Controller, dynamisk modellering och reglering för programvaran Neplan2002Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 115.
    Staltmanis, Arnis
    KTH, Superseded Departments, Electric Power Systems.
    Människamaskin gränssnitt i moderna system för övervakning av energisystem system för övervakning av moderna kraftsystem1996Independent thesis Advanced level (professional degree), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    missing

  • 116.
    Stenlund, Patrik
    KTH, Superseded Departments, Electric Power Systems.
    Analys av elkvalitet vid en pappersindustri1996Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Missing

  • 117.
    Ström, Mikael
    KTH, Superseded Departments, Electric Power Systems.
    Vindkraft och banmatning2000Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 118.
    Sulla, Francesco
    KTH, Superseded Departments, Electric Power Systems.
    Modeling of asynchronous Machines in Simpow2003Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 119.
    Sunden, Björn
    KTH, Superseded Departments, Electric Power Systems.
    Implementering av generell modell av kraftsystemautomatik1999Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 120.
    Svahn, Peter
    KTH, Superseded Departments, Electric Power Systems.
    Styrning av stora effektflöden i ett esxpanderande storstadsnät2004Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 121. Sveca, Julija
    et al.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Wind Power Integration in Areas with Congestion Problems and Storage Capabilities2003In: European Wind Energy Conference, Madrid, Spain, 2003Conference paper (Refereed)
  • 122.
    Sveca, Julija
    et al.
    KTH, Superseded Departments, Electric Power Systems.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Wind Power Integrations in Power Systems with Bottleneck Problems2002In: Vind2002 Conference, Malmö, Sweden, 2002Conference paper (Refereed)
  • 123.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Benefit assessment of wind power in hydro-thermal power systems1988Other (Other academic)
  • 124.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Reserve margin planning in a wind-hydro-thermal power system1993In: IEEE Transactions on Power Systems, ISSN 0885-8950, E-ISSN 1558-0679, Vol. 8, no 2, p. 564-570Article in journal (Refereed)
    Abstract [en]

    With a large-scale introduction of wind power the power system operation planning including keeping of spinning reserves will be influenced since extra uncertainties are introduced. To study this a more detailed analysis of system operation is required. This analysis has to consider wind speed forecast uncertainties, system load forecast uncertainties, ramp rates of thermal units and spinning reserves etc. This paper shows a new methodology to analyze the operation planning with an emphasis on keeping reserves. The result form the calculations include instantaneous, fast and slow reserve margins at each hour of the planning period.

  • 125.
    Söder, Lennart
    KTH, Superseded Departments, Electric Power Systems.
    Vindkraftens tillgänglighet vid hög elförbrukning1987Report (Other (popular science, discussion, etc.))
    Abstract [sv]

    Vindkraftens tillgänglighet vid hög elförbrukning har undersökts for 10 förbrukningstoppar under tidsperioden vintern 1979/80 - vintern 1986/87. En antagen installation av vindkraftverk vid 3 platser i Sverige har studerats. Genomsnittseffekten for dessa vindkraftverk vid studerade förbrukningstoppar skulle ha varit ungefär densamma som genomsnittseffekten under hela perioden jan 1980- dec 1985. Hypotesen "Det är vindstilla vid förbrukningstoppar" kan uteslutas. Hypotesen "Det är ofta vindstilla vid förbrukningstoppar kan inte bekräftas. Resultaten tyder på att det inte föreligger någon större skillnad mellan vindstyrkan vid förbrukningstoppar och vindstyrkan under det övriga året.

  • 126.
    Söder, Lennart
    et al.
    KTH, Superseded Departments, Electric Power Systems.
    Rendelius, Jonas
    Two-station equivalent of hydro power systems2005In: 15th Power Systems Computation Conference, PSCC 2005, Power Systems Computation Conference , 2005Conference paper (Refereed)
    Abstract [en]

    This paper studies the possible gains of representing hydropower systems with a new model consisting of two stations instead of the usual one station representation. The equivalent is obtained by solving an optimization problem where the aim is to find parameters which minimizes the difference in the production plans obtained from the two optimization problems corresponding to the original system and the equivalent respectively. This is in it self an uncommon optimization problem type. The paper also provides numerical examples.

  • 127.
    Takacs, Peter
    KTH, Superseded Departments, Electric Power Systems.
    Tillförlitlighetsvärdering av elsystem där kablar blandas med luftledningar2002Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 128.
    Taylor, Nathanniel
    KTH, Superseded Departments, Electric Power Systems.
    Nätåterverkan av direktstartade permanentmagnetiserade synkromnmotorer som ersättening för asynkronmotorer2001Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 129.
    Tegnevi, Rikard
    KTH, Superseded Departments, Electric Power Systems.
    Missing1995Independent thesis Advanced level (professional degree), 12 credits / 18 HE creditsStudent thesis
    Abstract [en]

    missing

  • 130.
    Thelin, Peter
    KTH, Superseded Departments, Electric Power Systems.
    Integration aspects and development of a compact 15 kW PM integral motor1999Licentiate thesis, monograph (Other scientific)
  • 131.
    Thunberg, Erik
    KTH, Superseded Departments, Electric Power Systems.
    Measurement based harmonic models of distribution systems1998Licentiate thesis, monograph (Other scientific)
  • 132.
    Thunberg, Erik
    KTH, Superseded Departments (pre-2005), Electric Power Systems.
    Optimal körplansberäkning baserad på dynamisk programmering1996Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Missing

  • 133.
    Thunberg, Erik
    et al.
    KTH, Superseded Departments, Electric Power Systems.
    Söder, Lennart
    KTH, Superseded Departments.
    Influence of the network impedance on distribution system harmonic Norton models2000In: PowerCon 2000. International Conference on Power System Technology, 2000. Proceedings., 2000, Vol. 3, p. 1143-1148Conference paper (Refereed)
    Abstract [en]

    The purpose of this paper is to study the influence of the network structure on a harmonic Norton model for a distribution network, estimated using measurements from different changes in the supply system. Using a simulated test system and a method of estimating a frequency coupled Norton admittance matrix (YN-matrix) of the modeled network, information about important parameters that influence the estimated Norton models can be found. The results received show that small off-diagonal elements of the network YN-matrix might result in different harmonic Norton models. The off-diagonal elements make the estimated harmonic Norton models sensitive to the change in the supply system. Since the change in harmonic voltage usually is greater for the lower harmonics, the results received for the lower harmonics will be better than for the higher harmonics. The results also show that the type of converters present in the network and the amount of capacitor banks connected in the network are the parameters that have the largest influence on the estimated harmonic Norton models

  • 134.
    Thunberg, Erik
    et al.
    KTH, Superseded Departments, Electric Power Systems.
    Söder, Lennart
    KTH, Superseded Departments.
    On the performance of a distribution network harmonic Norton model2000In: Ninth International Conference on Harmonics and Quality of Power, 2000. Proceedings., 2000, Vol. 3, p. 932-937Conference paper (Refereed)
    Abstract [en]

    The subject of this paper is to give some reflections and insight to when, and for which types of networks, the method of estimating a harmonic Norton model of a distribution system might be suitable. Using a small test system, simulated in the well-known simulation program EMTDC, the influence from some system parameters on the quality of the estimated harmonic Norton models is studied. The results received indicate that the method of estimating a harmonic Norton model, based on measurements from two different system operating conditions, is most suitable for cable distribution networks with typical household and office building loads. The results also indicate that for distribution networks where shunt capacitor banks are used, the 5th and 7 th harmonic network characteristics can accurately be represented with a harmonic Norton model

  • 135.
    Thärning, Peter
    KTH, Superseded Departments, Electric Power Systems.
    Watertree dielectric spectroscopy1997Licentiate thesis, monograph (Other scientific)
  • 136.
    Todorovic, Jovan
    KTH, Superseded Departments, Electric Power Systems.
    AC-teknik för anslutning av havsbaserad vindkraft2004Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 137.
    Wall, Daniel
    KTH, Superseded Departments, Electric Power Systems.
    Felströmsanalys - jämförelse av olika metoder2001Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 138.
    Watson, James
    KTH, Superseded Departments, Electric Power Systems.
    Strömtransformatorer eller - sensorer? En kritisk genomhång av strömmätning i skyddssystem.2002Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
  • 139. Werelius, P.
    et al.
    Thärning, P.
    Eriksson, Roland
    KTH, Superseded Departments, Electric Power Systems.
    Holmgren, B.
    Gäfvert, U.
    Dielectric spectroscopy for diagnosis of water tree deterioration in XLPE cables2001In: IEEE transactions on dielectrics and electrical insulation, ISSN 1070-9878, E-ISSN 1558-4135, Vol. 8, no 1, p. 27-42Article in journal (Refereed)
    Abstract [en]

    A HV dielectric spectroscopy system has been developed for diagnostics of water tree deteriorated extruded medium voltage cables. The technique is based on the measurement of nonlinear dielectric response in the frequency domain. Today's commercially available systems are capable of resolving low loss and small variations of permittivity as a function of frequency and voltage. Experience from more than 200 field measurements was combined with laboratory investigations. Small samples were used in an accelerated aging test to elucidate the correlation between water tree growth and dielectric response. Furthermore, field aged cables were investigated in the laboratory. It has been shown that the dielectric response of water tree deteriorated crosslinked polyethylene (XLPE) cables can be recognized and classified into different types of responses related to the aging status and breakdown strength. The influence of termination and artifacts such as surface currents was investigated. The measurement method enables us to separate the response of the cable from the influence of accessories. Finally, two different field studies of the implementation of the diagnostic method are presented. The field studies show that the fault rate decreased significantly when replacement strategy was based on the diagnostic criteria formulated.

  • 140.
    Wik, Marcus
    KTH, Superseded Departments (pre-2005), Electric Power Systems.
    Fördelning av energikostnader på flera tågoperatörer1994Student paper second term, 20 HE creditsStudent thesis
    Abstract [en]

    The Swedish Parliament has come to a decision that other companies than SJ, the Swedish State railways, will be given the opportunity to carry on railway traffic. The question then occurring is how to distribute the energy costs of Banverket, the Swedish National Rail Administration, among the companies operating on the railway network. Individual measurements may be a way of founding a basis for the energy cost distribution.

    The purpose of this work was originally to draw up a practical suggestion how to measure the electricitiy consumption of railway vehicles. The first step was to decide what to measure. Sol­ving this task took far more time than had been calculated for initially. To begin with, the que­stion whether measurements should be performed at all, had to be discussed.

    When the method of measuring had been chosen, several mathematical calculations had to be carried out, in order to justify the chosen method.

    The method can be described as follows: The active power consumption of the engine is mea­sured by an electrical energy meter. Furthermore, the square of the effective current in the cur­rent collector is measured by a similar energy meter. Using this method, there is no need for expensive computer equipment to registrate the instantaneous power consumption of the vehic­le.

    The first of these two measured values is used to charge the traffic operator for the active ener­gy being consumed. This will be the main part of the total energy cost.

    The second value , the square of the effective current, will represent in what way the vehicle has been driven, and thereby the losses being caused in the contact lines and in the frequency con­verters. Since we are dealing with the true rms current, both the reactive influence of the engine, and the current harmonics will be regarded.

    Firstly, knowing what has been fed into the power supply network, and secondly, what has been consumed as active power in the vehicles, it is possible to calculate the total losses in the net­work. These losses are in fact impossible to measure directly. This way of treating the problem how t() distribute the losses, is called totalförlustmodellen (model of total losses) in this work.

    To be able to use the square of the effective current as a measure of losses, it is necessary that the current value in average is not greatly affected by variations of the contact line impedance. The developped calculation model deals with this matter.

    The conclusion that can be drawn is that great power consumption will lead to a share too small for the vehicle, however giving us an error less than ten percent. It is possible to correct this deviation by forming a correction quotient from the two measured values. This quotient results in a correction factor that is used to correct the share.

  • 141.
    Wikström, Anders
    KTH, Superseded Departments, Electric Power Systems.
    Tillgänglig transmissionskapacitet i elkraftsystem1998Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
  • 142.
    Wolfbrandt, Anna
    et al.
    KTH, Superseded Departments, Electrical Systems.
    Magnusson, Niklas
    KTH, Superseded Departments, Electric Power Systems.
    AC losses in high-temperature superconducting tapes exposed to perpendicular magnetic fields combined with transport currents2002In: Superconductors Science and Technology, ISSN 0953-2048, E-ISSN 1361-6668, Vol. 15, no 4, p. 572-576Article in journal (Refereed)
    Abstract [en]

    AC losses are of great importance when designing devices for electric power applications based on high-temperature superconducting (HTS) tapes. In order to obtain an optimized design one needs to be able to calculate the AC losses that appear in an actual application. One important quantity is the AC losses that appear at the ends of a coil where the magnetic field contains a component perpendicular to the face of the tape. In this study we calculate the AC losses due to the combined action of a perpendicular magnetic field and a transport current. The results are compared to calorimetrically measured data of the AC losses in a BSCCO/Ag HTS tape.

  • 143.
    Wolfbrandt, Anna
    et al.
    KTH, Superseded Departments, Electrical Systems.
    Magnusson, Niklas
    KTH, Superseded Departments, Electric Power Systems.
    Hörnfeldt, Sven
    AC losses in a BSCCO/Ag tape carrying AC transport currents in AC magnetic fields applied in different orientations2001In: IEEE transactions on applied superconductivity (Print), ISSN 1051-8223, E-ISSN 1558-2515, Vol. 11, no 4, p. 4123-4127Article in journal (Refereed)
    Abstract [en]

    In most prospective electric power applications of high-temperature superconductors (HTSs), the conductor is wound in a coil configuration. For a coil of finite length, the magnetic field orientation is axial in the middle of the coil, while the field contains a substantial radial component at the coil ends. In a superconducting BSCCO/Ag tape, the ac losses depend strongly on the orientation of the magnetic field. In this study, we present experimental results of the ac losses in a multifilamentary silver-sheathed Bi-2223 HTSs tape, carrying alternating transport currents in externally applied alternating magnetic fields at different orientations, with respect to the face of the tape and perpendicular to the transport current. The ac losses were measured calorimetrically, at fixed temperature and frequency. The results are compared to semi-empirical models of the ac losses in HTSs tape. We present a more general model of the angular dependence of the ac losses.

  • 144.
    Wolfbrandt, Anna
    et al.
    KTH, Superseded Departments, Electrical Systems.
    Magnusson, Niklas
    KTH, Superseded Departments, Electric Power Systems.
    Hörnfeldt, Sven
    KTH, Superseded Departments, Electrical Systems.
    Temperature dependence of AC losses in a BSCCO/Ag tape exposed to AC magnetic fields applied in different orientations2002In: Physica. C, Superconductivity, ISSN 0921-4534, E-ISSN 1873-2143, Vol. 372, p. 1818-1822Article in journal (Refereed)
    Abstract [en]

    When high-temperature superconducting tapes are used in electrotechnical applications, they have an optimal working point in temperature. In the winding of e.g. a transformer the conductor carrying an AC current is exposed to an AC magnetic field oriented differently in separate parts of the winding. To determine the optimal working temperature it is essential to study the temperature dependence of the AC losses under these conditions. In this study, we present experimental results of the losses in a multi-filamentary silver-sheathed Bi-2223 high-temperature superconducting tape carrying an AC transport current in an AC magnetic field applied in different orientations perpendicular to the current path. The losses were measured calorimetrically in the temperature interval 40-85 K. The experimental results are compared to semi-empirical models of the AC losses.

  • 145.
    Zhao, Amanda Yushu
    KTH, Superseded Departments, Electric Power Systems.
    Effektförluster orsakade av övertoner1998Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
123 101 - 145 of 145
CiteExportLink to result list
Permanent link
Cite
Citation style
  • apa
  • harvard1
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf