To main content

Gunnar Berg-Karlsen

Research Scientist

Gunnar Berg-Karlsen

Research Scientist

Gunnar Berg-Karlsen
Phone: 924 58 111
Email:
Department: Electric Power Technology
Office: Trondheim

Publications and responsibilities

Publication
https://www.sintef.no/en/publications/publication/1907116/

In the years to come, large power grid operators will operate and maintain an ever-increasing asset base. New innovative solutions are needed to increase the quality and efficiency of asset management to avoid corresponding growth in resources and cost. To this end, autonomous unmanned aerial...

Authors Helge-André Langåker Håkon Kjerkreit Christoffer L Syversen Richard Moore Øystein Hov Holhjem Irene Anite Jensen Aiden James Morrison Aksel Andreas Transeth Oddgeir Kvien Gunnar Berg-Karlsen Thomas Olsen Alexander Hatlestad Thomas Negård Rolf Broch Jørn E Johnsen
Year 2021
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/1918843/

We report on the testing of a 1 m long and 0.5 m wide racetrack coil wound from 4.5 km of MgB2 tape-shaped superconductors with a copper strip soldered to the nickel matrix. The cross-section of the coil corresponds to what is needed for the field windings of a 10 MW direct drive wind turbine...

Authors Niklas Magnusson Svein Magne Hellesø R. Mikkonen A.B. Abrahamsen Magne E Runde Gunnar Berg-Karlsen Arne Nysveen
Year 2021
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/1907476/

Nye innovative løsninger er nødvendig for å øke kvaliteten og effektiviteten i kapitalforvaltningen for å unngå tilsvarende vekst i ressurser og kostnader. For dette formål gir autonome ubemannede fly (UAV) - eller droner - en rekke muligheter. Imidlertid har det ikke vært noen kjente løsninger på...

Year 2021
Type Lecture
Publication
https://www.sintef.no/en/publications/publication/1805177/

This paper presents results from laboratory measurements of partial discharge (PD) activity in stator bars taken from a 95 MVA hydrogenerator after 52 years in service. The generator has previously been subjected to off-line condition monitoring including partial discharge (PD) testing at both...

Year 2020
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/1619732/

Stator winding insulation is the part of the hydrogenerator experiencing the highest number and the most damaging failures. Partial discharge (PD) measurement, both offline and online, are commonly used for condition assessment and monitoring of electrical machines. The main concern of using very...

Year 2018
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/1385596/

We describe herein the design of a small AC electrostatic model coalescer for investigating coalescence efficiency of water in oil emulsions. The function of the model coalescer is tested on emulsions with different water cuts. In the coalescer, coalescence takes place in a couette flow in the bulk...

Publication
https://www.sintef.no/en/publications/publication/1246898/

Results are presented concerning the influence of an applied electric field on the coalescence of a water droplet with a much bigger water drop, both drops being immersed in a crude oil. This original study of electrocoalescence in crude oil was performed through high-speed optical observations...

Year 2015
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/990913/

Electrical demulsification is considered an elegant method to enhance the separation of water-in-crude-oil emulsions. Understanding the mechanisms involved during this process remains a challenge for the further development of this separation method. The aim of this study is to elucidate the...

Authors Cedric Lesaint Sebastien Charles Simon Caterina Lesaint Wilhelm R Glomm Gunnar Berg-Karlsen Lars Lundgaard Johan Sjøblom
Year 2013
Type Academic article