Publikasjoner og ansvarsområder
Ageing of liquid impregnated cellulose for power transformers
Compatibility of liquid and solid insulation materials for high voltage subsea connectors
The main objective of this study is to identify reliable insulation materials and systems for novel AC and DC subsea power connectors for oil and gas exploitation. A combined solid-liquid insulation system might be radically altered if the materials are not compatible. Different combinations of rele...
Material characterization of aged wet-design cable
Nanocomposites increase reliability and endurance of electrical insulation systems
Comparison between synthetic ester and mineral oil impregnated transformer paper aging markers
For transformers in service, aging markers from cellulose in oil such as furans, water, methanol and acids are measured for diagnostic purposes. The content of these indicators, measured in oil, may therefore vary with load, temperature, solid and liquid insulation aging, as well as marker stability...
Liquid insulation of IGBT modules: Long term chemical compatibility and high voltage endurance testing
To facilitate operation of power electronics for subsea operation at ambient pressure components have to be submerged in a liquid. Equipment and schemes for testing of long term properties have been developed. Several techniques were used to investigate compatibility between a silicone gel and vario...
A novel bench size model coalescer: Dehydration efficiency of AC fields on water-in-crude-oil emulsions
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 ...
Self-healing composites for high voltage electrical insulation
A self-healing electrical insulation material for high voltage apparatuses has yet not been developed. Such a material would have been very attractive for electrical components installed in conditions were service failures cause time consuming and very expensive replacements. This paper reports...