Search for dissertations about: "Lena Max"

Showing result 1 - 5 of 6 swedish dissertations containing the words Lena Max.

2. 1. Design and control of a DC collection grid for a wind farm

   Author : Lena Max; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DC collection grid; fault handling; DC DC converter; wind energy; control design; loss evaluation;

   Abstract : In this thesis, the internal DC collection grid for a wind farm is investigated regarding the design, losses and dynamic operation for both normal operating conditions and for different fault conditions. The main advantage for the DC collection grid is the considerably lower weight of the 1 kHz transformers in the DC/DC converters compared to the equivalent 50 Hz transformers. READ MORE

4. 2. Energy Evaluation for DC/DC Converters in DC-Based Wind Farms

   Author : Lena Max; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; DC DC converter; loss evaluation; measurements; hard switching converters; wind energy; resonant converters; snubber design;

   Abstract : In this thesis the suitability of three topologies for DC/DC converters in a DC wind farm grid is investigated from an energy efficiency and energy production cost point of view. The three selected topologies are the fullbridge converter, the single active bridge converter and the series parallel resonant converter. READ MORE

5. 3. Power control strategies for renewable energy systems : The inverter's role in future power systems

   Author : Sara Anttila; Cecilia Boström; Sandra Eriksson; Lena Max; Uppsala universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Renewable energy systems; Grid-connection; Inverter; Power control; Engineering Science with specialization in Science of Electricity; Teknisk fysik med inriktning mot elektricitetslära;

   Abstract : Connecting more non-dispatchable renewable energy sources (RESs) will result in a higher power variability and a lower system inertia when the synchronous generators are replaced by inverter-connected RES. Inverter control can be divided in three categories: grid-following, grid-forming (GFM) and grid-supporting. READ MORE

6. 4. Macroalgae in tropical seascapes : regulating factors and functions in the coastal ecosystem

   Author : Gustaf Lilliesköld Sjöö; Max Troell; Nils Kautsky; Lena Kautsky; Alina Szmant; Stockholms universitet; []
   Keywords : NATURVETENSKAP; NATURAL SCIENCES; Macroalgae; Coral reefs; Nutrients; Herbivory; Ecological functions; East Africa; Regulating factors; Anthropogenic influence; Seaweed farming; Bioindicator; marin ekotoxikologi; Marine Ecotoxicology;

   Abstract : Although macroalgae usually are inconspicuous on pristine coral reefs, they often thrive on reefs that are subjected to various types of anthropogenic disturbance. This thesis consists of five papers and investigates how biomass and composition of macroalgal communities on coral reefs are affected by regulating factors, such as nutrient availability, herbivory, substrate availability and hydrodynamic forces. READ MORE

7. 5. Physiology and productivity of serum-free Spodoptera frugiperda Sf9 insect cell cultures

   Author : Eva Lindskog; Lena Häggström; Spiros N. Agathos; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Animalcellteknologi; Bioengineering; Bioteknik;

   Abstract : The objective of this study was to investigate the mechanisms and factors controlling growth and proliferation in serum-free Spodoptera frugiperda Sf9 cultures as well as the implications of these factors for protein production in the baculovirus expression system. The physiology of recently thawed, low passage (Lp) Sf9 cultures, were compared to high passage (Hp) cultures at p>100. READ MORE