Browsing NTNU Open by Author "Runde, Magne"
Now showing items 1-16 of 16
-
Ablation-Assisted Current Interruption in a Medium Voltage Load Break Switch: An Experimental Study with Polypropylene as Ablation Material
Gjendal, Gaute Jensen (Master thesis, 2014)Near an electric arc some polymers can change the properties of an arcing medium in a beneficial manner. Such polymers, known as ablation material, decompose and evaporate when exposed to heat from an electric arc. The ... -
Ablation-assisted load switching at medium voltage in an alternative gas to sulphur hexafluoride
Røren, Paul Monceyron (Doctoral theses at NTNU;2024:354, Doctoral thesis, 2024)Anthropogenic emission of green house gases is currently one of the challenges facing humanity. Just as Chlorofluorocarbons were harming the ozone layer, the emission of Sulphur hexafluoride, along with other gases, are ... -
AC loss measurements multi-filamentary MgB2 wires with non-magnetic sheath material
Taxt, Henning; Magnusson, Niklas; Runde, Magne; Brisigotti, S (Journal article; Peer reviewed, 2012)The MgB2 superconductor is an attractive choice for many high-current DC applications, particularly for its low cost compared to e.g. YBCO, and the higher operating temperature than the low-temperature superconductors. To ... -
Air Flow Measurements During Medium-Voltage Load Current Interruptions
Aanensen, Nina Sasaki; Runde, Magne (Journal article; Peer reviewed, 2015)Air has been considered a good alternative to SF6 as arc quenching medium for load break switchgear at medium voltage ratings. In this work, the air flow characteristics and influence from the electric arc have been studied ... -
Aluminium Fuses for Li-ion Battery Systems
Holtet, Trym Leivestad (Master thesis, 2021)Abstract will be available on 2024-06-28 -
Apparatus for calorimetric measurements of losses in MgB2 superconductors exposed to alternating currents and external magnetic fields
Taxt, Henning; Magnusson, Niklas; Runde, Magne (Journal article; Peer reviewed, 2013)Inexpensive superconducting wires with low AC losses would open up for a large superconductor market in AC electrical power applications. One candidate for this market is the MgB2 conductor. In the development of an AC ... -
Arc Voltage Characteristics in Ultrahigh-Pressure Nitrogen Including Supercritical Region
Abid, Fahim; Niayesh, Kaveh; Jonsson, Erik; Støa-Aanensen, Nina Sasaki; Runde, Magne (Journal article; Peer reviewed, 2017)A supercritical (SC) fluid is formed when both pressure and temperature of a fluid exceed the critical point, where distinct gas and liquid phases no longer exist. SC fluids demonstrate combined properties of gas and liquid, ... -
Coupling currents and hysteresis losses in MgB2superconductors
Magnusson, Niklas; Lindau, Sandra Madeleine; Taxt, Henning; Runde, Magne (Journal article; Peer reviewed, 2014)MgB2 multi-filamentary superconductors are widely considered for use in dc applications. To expand the possible application range to ac apparatuses, the development of a low ac loss wire is needed. This development involves ... -
Experimental investigation on ablation-assisted current interruption - Experimental setup and preliminary results
Taxt, Henning; Niayesh, Kaveh; Jonsson, Erik; Runde, Magne (Chapter, 2016)This paper presents a flexible setup to investigate ablation-assisted interruption of load currents. The electrical test circuit is grid connected with a transformer secondary voltage from 6.9 kV to 24 kV. The applied ... -
Fabrication of a scaled MgB2 racetrack demonstrator pole for a 10 MW direct drive wind turbine generator
Magnusson, Niklas; Eliassen, J. C.; Abrahamsen, Asger B; Hellesø, Svein Magne; Runde, Magne; Nysveen, Arne; Moslått, Lars-Erik; Bjerkli, Jarle; King, Patrick (Journal article; Peer reviewed, 2018)Field windings made of MgB2 wires or tapes are considered for their potential to reduce volume, weight and cost of large offshore wind turbine generators. To gain experience of how to use this relatively new material in ... -
Investigation on Fault Current Making in Medium Voltage Switchgear in Air
Dorraki, Naghme (Doctoral theses at NTNU;2022:106, Doctoral thesis, 2022)Closing a switch under a fault condition could result in extensive electrical contact wear and a possible switch failure. A load break switch (LBS), as one of the critical components in medium voltage (MV) power grids, ... -
Large Superconducting Wind Turbine Generators
Abrahamsen, A.B.; Magnusson, Niklas; Jensen, B.B.; Runde, Magne (Journal article; Peer reviewed, 2012)To realize large (>10 MW) direct-driven off-shore wind turbines, a number of steps are needed to reduce weight and cost compared to on-shore technologies. One of the major challenges is to provide drive trains which can ... -
MEDIUM VOLTAGE LOAD BREAK SWITCH WITH AIR AS INTERRUPTING MEDIUM
Teigset, Anders Dall'Osso (Master thesis, 2014)Compact load break switches (LBSs) are common inside compact substations, and other places in the medium voltage distribution system where space is a limiting factor. SF6 is usually applied as interruption and insulation ... -
Medium voltage load current interruption in presence of ablating polymer material
Taxt, Henning; Niayesh, Kaveh; Runde, Magne (Journal article; Peer reviewed, 2018)The expected abolishment of SF6-gas in medium voltage switchgear has prompted a search for replacements for the switch types that depend on SF6 to obtain the required capability, reliability, compactness and cost. Ablation ... -
Self-blast Current Interruption and Adaption to Medium Voltage Load Current Switching
Taxt, Henning; Niayesh, Kaveh; Runde, Magne (Journal article; Peer reviewed, 2019)Ablation-assisted current interruption is a candidate for improving interruption capability in medium voltage switchgear. In high voltage switchgear, ablation is utilized to achieve high pressures in self-blast circuit ... -
Testing of an MgB2 coil for a wind turbine generator pole
Magnusson, Niklas; Hellesø, Svein Magne; Mikkonen, R.; Abrahamsen, A.B.; Runde, Magne; Berg, Gunnar; Nysveen, Arne (Peer reviewed; Journal article, 2021)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 ...