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Lars Lundgaard

Chief Scientist

Lars Lundgaard

Chief Scientist

Lars Lundgaard
Phone: 930 07 018
Email:
Department: Electric Power Technology
Office: Trondheim

Publications and responsibilities

Publication
https://www.sintef.no/en/publications/publication/?pubid=1807148

This study addresses the dielectric performance of nonpolar hydrocarbon liquids and mineral oils under positive polarity stress. It is of interest to improve knowledge on how functional properties of dielectric liquids vary, as new brands arrive in the market, and existing standards are unsuited for...

Authors Dag Linhjell Lars Esben Lundgaard Michael Unge Olof Hjortstam
Year 2020
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/?pubid=1807150

This study addresses the dielectric performance of nonpolar hydrocarbon liquids and mineral oils under negative polarity stress. Stopping length for non-breakdown streamers, breakdown voltages and velocities for various pre-breakdown streamer modes have been studied for a selection of model liquids ...

Year 2020
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/?pubid=1816551

The effect of pressure on positive and negative streamer propagation in a mineral transformer oil is studied in an 80 mm point-plane gap under step voltage. Increased pressure causes reduced stopping length for non-breakdown streamers, higher breakdown voltage, reduced background current, reduced br...

Authors Dag Linhjell Lars Esben Lundgaard M. Unge Olof Hjortstam
Year 2020
Type Academic article
Publication
https://www.sintef.no/en/publications/publication/?pubid=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 ...

Authors Dag Linhjell Lars Esben Lundgaard Mikael Unge
Year 2019
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/?pubid=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 ...

Year 2017
Type Academic chapter/article/Conference paper
Publication
https://www.sintef.no/en/publications/publication/?pubid=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...

Year 2017
Type Academic chapter/article/Conference paper