Search for dissertations about: "system modelling"

Showing result 21 - 25 of 1461 swedish dissertations containing the words system modelling.

  1. 21. Hydropower generator and power system interaction

    Author : Johan Bladh; Urban Lundin; Rafael Escarela-Perez; Uppsala universitet; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Amortisseur windings; applied voltage test; automatic voltage regulators; damper windings; damping torque; empirical modelling; equivalent circuits; excitation control; finite element method; hydropower generators; power system restoration; power system stability; synchronous machines; self excitation; shaft torque amplification; short circuit test; single machine infinite bus; slip test; standstill frequency response test; subsynchronous oscillations; synchronising torque; synchronous generators; torsional interaction.; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

    Abstract : After decades of routine operation, the hydropower industry faces new challenges. Large-scale integration of other renewable sources of generation in the power system accentuates the role of hydropower as a regulating resource. READ MORE

  2. 22. Design of Thermal Barrier Coatings : A modelling approach

    Author : Mohit Kumar Gupta; Per Nylén; Nicolaie Markocsan; Christer Persson; Lech Pawlowski; Högskolan Väst; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Thermal barrier coatings; Microstructure; Thermal conductivity; Young’s modulus; Interface roughness; Thermally grown oxide; Lifetime; Finite element modelling; Design; Manufacturing and materials engineering; Produktions- och materialteknik;

    Abstract : Atmospheric plasma sprayed (APS) thermal barrier coatings (TBCs) are commonly used for thermal protection of components in modern gas turbine application such as power generation, marine and aero engines. TBC is a duplex material system consisting of an insulating ceramic topcoat layer and an intermetallic bondcoat layer. READ MORE

  3. 23. Studies in Glacier Mass Balance : Measurement and its errors

    Author : Andrew Mercer; Peter Jansson; Gunhild Rosqvist; Ian Brown; Jonathan Carrivick; Stockholms universitet; []
    Keywords : NATURVETENSKAP; NATURAL SCIENCES; Glaciology; Mass Balance; Measurement Errors; Physical Geography; naturgeografi;

    Abstract : The study of the surface mass balance of valley glaciers has a long history but one that is dogged by uncertainty and errors, and uncertainty about those errors. These problems are acknowledged by the glaciological community and have been examined and formalised in several publications. READ MORE

  4. 24. Failure of thermal barrier coatings under thermal and mechanical fatigue loading : microstructural observations and modelling aspects

    Author : Håkan Brodin; Anette M. Karlsson; Linköpings universitet; []
    Keywords : thermal barrier coating; TBC; delamination; crack initiation; crack propagation; crack growth; oxidation; alumina; spinel; MCrAIY; diffusion; fatigue; modelling; modeling; degradation; TECHNOLOGY; TEKNIKVETENSKAP;

    Abstract : Industrial and air-borne gas turbine hot components suffer from creep, oxidation, corrosion and microstructural degradation if not shielded from the hot and aggressive combustion gases. Two major strategies commercially available are adopted; film cooling by pressurised air and application of protective coatings. READ MORE

  5. 25. On impacts and ride-through of voltage sags exposing line-operated AC-machines and metal processes

    Author : Fredrik Carlsson; KTH; []
    Keywords : Rolling mill; Blast furnace; Power Quality; Synchronous machine; Asynchronous machine; Voltage sag; Voltage interruption; Ride-through; Process disturbances; Simulation; Modelling;

    Abstract : During the last decade, power quality has been recognised asa global problem. Among different types of power qualityproblems, voltage sags have been identified to be one of themost severe problems for different process industries. The mostcommon reason to voltage sags is lightning strikes in powerlines. READ MORE