Browsing Publikasjoner fra CRIStin - SINTEF Energi by Author "Ildstad, Erling"
Now showing items 1-7 of 7
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A stochastic model for contact surfaces at polymer interfaces subjected to an electrical field
Kantar, Emre; Hvidsten, Sverre; Mauseth, Frank; Ildstad, Erling (Journal article; Peer reviewed, 2018)Morphology of the contact area between solid insulation materials ultimately determines the short- and long-term electrical properties of the complete insulation system. The main purpose of this paper is to propose a ... -
AC Breakdown Voltage of 50-Year-Old Service Aged Hydro Power Generator Stator Bars
Aakre, Torstein Grav; Ildstad, Erling (Peer reviewed; Journal article, 2022)Randomly selected generator bars from a 50-year-old Norwegian hydro power generator were examined in this work. Typical non-destructive tests, as partial discharge and dissipation factor measurements were initially performed ... -
Condition Assessment of Hydrogenerator Stator Bar Insulation Using Partial Discharge Measurements
Aakre, Torstein Grav; Ildstad, Erling; Hvidsten, Sverre (Chapter; Peer reviewed, 2018)This paper presents results from laboratory measurements of partial discharge (PD) activity in 50 cm long samples cut from the mainwall section of old hydrogenerator stator bars. All stator bars were manufactured in 1976 ... -
Effect of Elastic Modulus on the Tangential AC Breakdown Strength of Polymer Interfaces
Kantar, Emre; Ildstad, Erling; Hvidsten, Sverre (Journal article; Peer reviewed, 2019)Solid-solid interfaces between insulating materials dictate the long-term electrical properties of the complete insulation system. This paper presents theoretical and experimental investigations aiming to address the impact ... -
Effect of Material Elasticity on the Longitudinal AC Breakdown Strength of Solid-Solid Interfaces
Kantar, Emre; Ildstad, Erling; Hvidsten, Sverre (Journal article; Peer reviewed, 2019) -
HydroStator : hovedfunn og resultater i KPN-prosjektet HydroStator
Berg, Gunnar; Eberg, Espen; Aakre, Torstein Grav; Ildstad, Erling; Kantar, Emre; Nysveen, Arne (SINTEF Rapport;, Research report, 2022)Modeller som beskriver temperatur- og frekvensavhengighet til elektriske delutladninger er utviklet og viser at tilstandskontroll med den mer praktiske VLF-metoden som benytter 0,1 Hz høyspenning er representativ for 50 ... -
Modelling and Characterization of Partial Discharge Activity versus Applied Voltage, Test Frequency and Temperature
Ildstad, Erling; Aakre, Torstein Grav (Chapter; Peer reviewed, 2022)Measurements of partial discharges (PDs) are commonly used as diagnostic indicators for assessing the quality of high voltage equipment. In many cases, such PD measurements are of practical reasons either performed at ...