Sökning: "electric resistance"

Visar resultat 6 - 10 av 108 avhandlingar innehållade orden electric resistance.

1. 6. On reliability and maintenance modelling of ageing equipment in electric power systems

   Författare :Tommie Lindquist; Roland Eriksson; Lina Bertling; George Anders; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Reliability; maintenance; electric power systems; circuit breaker; disconnector; thermography; Electric power engineering; Elkraftteknik;

   Sammanfattning : Maintenance optimisation is essential to achieve cost-efficiency, availability and reliability of supply in electric power systems. The process of maintenance optimisation requires information about the costs of preventive and corrective maintenance, as well as the costs of failures borne by both electricity suppliers and customers. LÄS MER

3. 7. Lithium ion Battery Aging: Battery Lifetime Testing and Physics-based Modeling for Electric Vehicle Applications

   Författare :Evelina Wikner; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Physics-based modeling; Electric Vehicle EV ; Battery lifetime tests; Hybrid Electric Vehicle HEV ; Plug-in Hybrid Electric Vehicle PHEV ; Calendar aging;

   Sammanfattning : Electrification of vehicles is one solution in reducing emissions from the transport sector, and in particular to limit tail-pipe emissions in cities. In order to make the electrification successful and cost effective, there is a high demand for longer drive range and longer battery lifetime. LÄS MER

4. 8. Analysis of Deformation of Gas Diffusion Layers and the Impact on Performance of PEM Fuel Cells

   Författare :Jiatang Wang; Värmeöverföring; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; PEM fuel cell; compression ratio; assembly pressure; porosity; deformed GDL; electric resistance; transport phenomena; model; performance; analysis; OpenFOAM;

   Sammanfattning : Proton exchange membrane (PEM) fuel cells have been promoted due to significant breakthroughs in various aspects and increasing public interests. The porous features of the gas diffusion layer (GDL) and the necessary assembly processes generate localized pressure forces on the channel/shoulder structure of the bi-polar plates (BPP). LÄS MER

5. 9. Battery thermal management for electric vehicles operating in cold climates

   Författare :Anandh Ramesh Babu; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; battery pack encapsulation; electric vehicle; battery modeling; lithium-ion battery; low-temperature performance;

   Sammanfattning : Electromobility has gained significance over recent years in an attempt to reduce greenhouse gas emissions which contribute to climate change. The requirements on the performance and efficiency of electric vehicles are high to make them an attractive alternative to the conventional fossil-fuel driven vehicles. LÄS MER

7. 10. Investigating ageing mechanisms in electric vehicle batteries : A multiscale approach to material analysis

   Författare :Anastasiia Mikheenkova; Maria Hahlin; Matthew Lacey; Cesar Pay Gómez; Sandrine Lyonnard; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Li-ion batteries; Ni-rich cathode; Ageing mechanisms; Batteries for electric vehicles; X-ray diffraction; NCA; NMC811; Kemi med inriktning mot materialkemi; Chemistry with specialization in Materials Chemistry;

   Sammanfattning : Electrifying passenger transport is a key strategy in combating global warming, with Li-ion batteries (LIBs) being the current go-to technology. Despite LIB’s satisfactory performance and carbon-neutral operation, lifetime and safety are still public concerns. LÄS MER