Enhanced charge injection in rough HVDC extruded cable interfaces
Journal article, 2019

The insulation system of an HVDC extruded cable includes a variety of different material interfaces, especially within its cable accessories. Depending on interfacial manufacturing method, different degrees of surface roughness can be found and are here assessed. Based on detailed knowledge of insulation surface roughness, this paper proposes a new approach for calculations of electrical field distributions and injection current densities at the insulation surface. It is shown that local fields at rough material interfaces can be greatly enhanced, resulting also in field reduction in other areas along the surface. These calculations also reveal a distinct field threshold for space charge injection, likely leading to formation of homocharge layer adjacent to the interface. Existence of this homocharge layer at a rough surface (density of approximately 1 C/m(3)) is confirmed by means of space charge measurements.

charge injection

space charge measurement

HVDC extruded cable

cable peelings

field enhancement factor

physical interfaces

surface roughness

Author

Espen Doedens

Chalmers, Electrical Engineering, Electric Power Engineering, Power grids and Components

Nexans Norway AS

E. Markus Jarvid

Nexans Norway AS

Christian Frohne

Nexans Germany GmbH

Stanislaw Gubanski

Chalmers, Electrical Engineering, Electric Power Engineering, Power grids and Components

IEEE Transactions on Dielectrics and Electrical Insulation

1070-9878 (ISSN)

Vol. 26 6 1911-1918

Subject Categories

Materials Chemistry

Other Chemistry Topics

Condensed Matter Physics

DOI

10.1109/TDEI.2019.008213

More information

Latest update

1/24/2020