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Gunnar Berg

Research Scientist

Gunnar Berg

Research Scientist

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

Publications and responsibilities

Publication
https://www.sintef.no/en/publications/publication/?pubid=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 0.1 a...

Year 2020
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/?pubid=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 lo...

Year 2018
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/?pubid=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/?pubid=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, usi...

Year 2015
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/?pubid=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 influen...

Authors Cedric Michel Lesaint Sebastien Charles Simon Caterina Lesaint Wilhelm Glomm Gunnar Berg Lars Esben Lundgaard Johan Sjøblom
Year 2013
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/?pubid=938785

The purpose of this work was to study the effect of hydrostatic pressure on the initiation and growth of electrical trees in a silicone insulation material for electrical apparatus. In this study a commercial available light transparent silicone material was subjected to a hydrostatic pressure in th...

Year 2012
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/?pubid=907558

High voltage apparatus and reliable power supply are of vital importance for subsea processing. The purpose of this work has been to develop a small high voltage penetrator for use with high pressure vessels in the laboratory. Such equipment can facilitate high voltage and current testing of models ...

Year 2011
Type Academic article