Jacket structure for optical cables, for use in high-voltage environments
AssigneeNKF Kabel B.V.
InventorAlbert V. Herrebrugh
Life of this patent
Estimating the term…
Abstract
Cladding structure, in particular for optical cables (1), for use in high-voltage environments, comprising at least one elongated plastic outer sheath (8), having capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) electrically connected in series in the longitudinal direction of the cladding structure. Said capacitive elements are formed by electrodes (5, 7, 9; 10, 11, 12) underneath the outwardly facing side of the outer sheath (8). Said electrodes (5, 7, 9; 10, 11, 12) can be situated in a mutually offset manner in radial and/or longitudinal direction of the cladding structure. Damaging of the cladding structure due to corona discharge or tracking phenomena is effectively reduced by said series connection of capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n).
Claims20
A jacket structure for energy-transmissive cables (1) intended for use in a high-voltage environment, said jacket structure comprising:
- a) at least one elongated plastic outer sheath (8) with an external surface extending in a longitudinal direction and subject to the formation of interrupted, conductive layers on said external surface;
- and
- b) a plurality of capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) disposed along, and electrically connected in series in said longitudinal direction of said outer sheath (8), said capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) being covered by said external surface of said outer sheath (8);
- whereby said jacket structure forms a capacitive voltage divider to limit voltage differences across said conductive layer interruptions and prevent undesired discharges.
An optical cable (1) intended for use in a high-voltage environment, said optical cable comprising a core of one or more optical fibers and a jacket structure, said jacket structure comprising:
- a) at least one elongated plastic outer sheath (8) with an external surface extending in a longitudinal direction and subject to the formation of interrupted, conductive layers on said external surface;
- and
- b) a plurality of capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) disposed along, and electrically connected in series in said longitudinal direction of said outer sheath (8), said capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) being covered by said external surface of said outer sheath (8);
- whereby said jacket structure forms a capacitive voltage divider to limit voltage differences across said conductive layer interruptions and prevent undesired discharges.
A self-supporting optical cable for use as a suspension cable in an electrical environment of high-voltage overhead lines, said optical cable comprising:
- a) a central core (15) of electrically insulating material;
- b) one or more optical fibers (16) supported by said central element (15);
- c) an electrically insulating sheath (17) surrounding each said fibre (16) with limited freedom of movement of a fibre (16) within said sheath (17);
- d) a belt (18) of electrically insulating material around said sheathed fibers (16);
- and
- e) a jacket structure (19-22) of electrically insulating material and comprising:
- i) a reinforcing layer (20);
- ii) an elongated outer sheath (22) with an external surface extending in a longitudinal direction;
- and
- iii) a plurality of capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) disposed along, and electrically connected in series in said longitudinal direction of said outer sheath (8), said capacitive elements (C.sub.1, C.sub.2, C.sub.3 . . . C.sub.n) being covered by said external surface of said outer sheath (8).
Dependencies are inferred from the claim text.