Search for dissertations about: "EFFICIENCY ELECTRICAL ENERGY"

Showing result 1 - 5 of 511 swedish dissertations containing the words EFFICIENCY ELECTRICAL ENERGY.

  2. 1. Energy Savings Using a Direct Current Distribution Network in a PV and Battery Equipped Residential Building

    Author : Patrik Ollas; Caroline Markusson; Mattias Persson; Torbjörn Thiringer; Jan-Olof Dalenbäck; RISE; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; LANTBRUKSVETENSKAPER; AGRICULTURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Direct-Current Distribution; Residential Buildings; Battery Energy Storage System; Battery Modeling; Solar Photovoltaic System; System Performance; Energy Efficiency; Energy Savings; PV Utilisation;

    Abstract : Energy from solar photovoltaic (PV) are generated as direct current (DC) and almost all of today’s electrical loads in residential buildings, household appliances and HVAC system (Heating Ventilation and Air-conditioning) are operated on DC. For a conventional alternating current (AC) distribution system this requires the need for multiple conversion steps before the final user-stage. READ MORE

  4. 2. Increasing Energy Efficiency in Electric Trains Operation : Driver Advisory Systems and Energy Storage

    Author : Nima Ghaviha; Erik Dahlquist; Markus Bohlin; Fredrik Wallin; Rob M.P. Goverde; Mälardalens högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Driver Advisory System; Catenary-free Operation; Electric Train; Electric Multiple Unit; Battery; Energy Efficiency; Energy Storage; Speed Profile Optimization; Energy- and Environmental Engineering; energi- och miljöteknik;

    Abstract : Electric traction is the most efficient traction system in the railway transportation. However, due to the expensive infrastructure and high power demand from the grid, the share of electric trains in the railway transportation is still lower than other trains. READ MORE

  5. 3. Modulation, efficiency and lifetime of two-level and multilevel converters for a hydropower application

    Author : Chengjun Tang; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Pumped-storage hydropower; pulse width modulation; losses; modular multilevel converter; efficiency; variable speed; converter; lifetime; space vector modulation; thermal modelling; neutral point clamped converter;

    Abstract : Along with the integration of the renewable energy in the electrical grid, the pumped-storage hydropower has gained more and more attention due to its fast response and energy storage ability. To have a higher overall efficiency and more flexibility of the system, variable speed is preferred in the operation of the pumped-storage hydropower applications. READ MORE

  6. 4. Modular Battery Systems for Electric Vehicles based on Multilevel Inverter Topologies - Opportunities and Challenges

    Author : Anton Kersten; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Dynamic reconfiguration; Energy storage; Energy efficiency; Drive cycle efficiency; Power MOSFET; vehicles; H-bridge; Multilevel systems; Electromagnetic compatibility; Modular battery systems; Battery system performance; Modular multilevel converters; Conduction losses; Electric vehicles; Batteries; Dual battery pack; Cascaded converters; DC-AC power converters; BMS; Common mode noise; Battery modeling; vehicle electrification;

    Abstract : Modular battery systems based on multilevel inverter (MLI) topologies can possibly overcome some shortcomings of two-level inverters when used for vehicle propulsion. The results presented in this thesis aim to point out the advantages and disadvantages, as well as the technical challenges, of modular vehicle battery systems based on MLIs in comparison to a conventional, two-level IGBT inverter drivetrain. READ MORE

  7. 5. Supermarket refrigeration systems for demand response in smart grids

    Author : Tommie Månsson; Chalmers tekniska högskola; []
    Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Supermarket; Demand-side management; Smart-Grid; Energy efficiency; Food retail; Demandresponse; Thermal modelling; Refrigerated Display Cabinet; Renewable energy;

    Abstract : With an increasing share of intermittent renewable energy sources in the electrical grid, the need for adapting the demand to the available supply of electricity becomes increasingly important. Within this thesis, the demand response capacity by supermarket refrigeration systems are investigated and methods for enabling it is developed. READ MORE