Original scientific paper
Conductivity of Pressboard for HVDC Insulation Systems
Fabian Schober
; University of Applied Sciences Würzburg-Schweinfurt, Institute for Power Engineering and High Voltage Technology
Stephan Harrer
; University of Applied Sciences Würzburg-Schweinfurt, Institute for Power Engineering and High Voltage Technology
Andreas Küchler
; University of Applied Sciences Würzburg-Schweinfurt, Institute for Power Engineering and High Voltage Technology
Frank Berger
; Technische Universität Ilmenau, Department of Electrical Apparatus and Switchgear
Marcus Liebschner
; Aalen University, Optics and Mechatronics
Christoph Krause
; Weidmann Electrical Technology AG, Technology Services and Innovation
Wolfgang Exner
; Weidmann Electrical Technology AG, Technology Services and Innovation
Abstract
The cellulosic material pressboard is a key component in insulation systems for HVDC (high-voltage direct current) equipment. Pressboard compounds are considered from a chemical point of view in order to link it in a subsequent study with electric conduction processes in pressboard. For a better understanding of pressboard, its manufacturing is described and fiber geometry is evaluated by SEM (scanning electron microscopy) analyses. Especially for HVDC insulation, pressboard conductivity is the most important property. For an air-impregnated pressboard sample, the dependence of conductivity on time, temperature and water content is presented. For this purpose, step response measurements in time domain are performed with a sensitive current device. Furthermore, the influence of oil-impregnation on pressboard conductivity is evaluated. The conductivity of oil-impregnated pressboard is up to 13 times higher than the conductivity of unimpregnated pressboard for the given conditions.
Keywords
cellulose; conductivity; HVDC transmission; insulation; pressboard
Hrčak ID:
133197
URI
Publication date:
20.11.2013.
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