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Lars Lundgaard

Sjefforsker

Lars Lundgaard

Sjefforsker

Lars Lundgaard
Telefon: 930 07 018
Avdeling: Elkraftteknologi
Kontorsted: Trondheim

Publikasjoner og ansvarsområder

Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1717940

The propagation of positive streamers in a naphtenic transformer oil in an 80 mm point-plane gap has been investigated under an impulse voltage being close to a step voltage and under pressures ranging from 0.1 to 1.7 MPa. As has previously been found in short gap experiments of 1 – 7 mm in various ...

Forfattere Linhjell Dag Lundgaard Lars Esben Unge Mikael
År 2019
Type Del av bok/rapport
Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1526050

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...

Forfattere Liland Knut Brede Linhjell Dag Lesaint Cedric Michel Ese Marit-Helen Glomm Lundgaard Lars Esben Mavrommatis Pascal Stjepanovic Nenad Miroljub
År 2017
Type Del av bok/rapport
Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1526045

An automated setup for testing dielectric performance of liquids in a small point-to-plane gap is presented. It provides step voltages with rise times around 30 ns, with amplitudes up to 90 kV. Breakdown studies of thirteen different liquids were conducted with a gap distance of 4 mm in a test cell ...

Forfattere Aakre Torstein Grav Lundgaard Lars Esben Unge Mikael
År 2017
Type Del av bok/rapport
Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1526028

A sensitive differential charge measurement technique was used to measure the conduction current from a sharp needle in a needle plane geometry in n-pentane. The current was measured at voltages up to the threshold for streamer inception in n-pentane with a positive needle polarity. The measured cur...

Forfattere Hestad Øystein Leif Gurandsrud Linhjell Dag Lundgaard Lars Esben Samseth Jarl Ø. Unge Mikael
År 2017
Type Del av bok/rapport
Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1526026

Third mode streamers have been studied in the mineral oil Nytro 10 XN, gas-to-liquid oil Diala S4 ZX-1 and the high viscosity white oil Primol 352, in an 80 mm point-plane gap under step impulse voltage. Third mode streamer velocities were in the range 4–60 km/s. The "acceleration" of the ...

Forfattere Linhjell Dag Lundgaard Lars Esben Unge Mikael
År 2017
Type Del av bok/rapport
Publikasjon
https://www.sintef.no/publikasjoner/publikasjon/?pubid=CRIStin+1385663

For introducing power converters at ambient pressure at large sea depths, dielectric liquids are proposed as insulation for power electronic converters. This paper presents statistical analysis of short time tests of partial discharge and breakdown voltage on the trench between metallized edges of p...

Forfattere Abdelmalik Abdelghaffar Amoka Borge Malin Drevdal Nysveen Arne Lundgaard Lars Esben Linhjell Dag
År 2016
Type Tidsskriftspublikasjon