JPH0438426Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention relates to a metal wire composite single-core power cable that combines a metal wire with a single-core power cable such as a single-core OF cable or a single-core cross-linked polyethylene insulated cable. be.

(Background of the invention) As shown in Fig. 3, a conventional metal wire composite power cable has one or more metal wires arranged in the gap between three power wire cores.

In the drawing, 10 is a power line core, power line core 1
A metal wire A is arranged in the intertwisting gap between the three cores of 0, and they are twisted together in a circle together with an inclusion 11, and a metal sheath 12 is provided on the outside to form a metal wire composite power cable.

However, in recent years, demand for single-core power cables has increased as the capacity of underground power transmission lines has increased. Especially for submarine cables, we aim to reduce cable installation costs and reduce the area occupied by the seabed.
There is an increasing demand for combining metal wires with functions such as signal transmission and low-power power transmission into single-core power cables. However, single-core power cables do not have gaps for arranging metal wires like three-core power cables, so despite the above requests, metal wire composite single-core power cables have not been realized. is the current situation.

Therefore, in order to realize a metal wire composite single-core power cable, it is necessary not only to select the space where the metal wires are placed, but also to be able to easily take out the composite metal wires.
It is important to take into account the above to ensure that the original electrical characteristics of the power cable are not impaired.

(Disclosure of the Invention) The present invention provides a metal wire composite single-core power cable that has fulfilled the above-mentioned requirements. A metal wire with functions such as communication, signal transmission, and low-power transmission is inserted into a continuous recess formed when the cable is spirally wound around the cable core.

FIG. 1 is an explanatory diagram of a specific example of a metal wire composite single-core power cable according to the present invention, and is a cross-sectional view. In this specific example, a single-core OF cable is used as the power cable, but it goes without saying that a cross-linked polyethylene cable or a solid type oil-paper insulated power cable can be similarly implemented.

In the drawing, A is a cable core, which comprises an oil-impregnated paper insulation layer 3 on a cable conductor 1 having an oil passage 2 inside, and an outer shielding layer and an optional copper wire woven cloth tape wrapping layer (any one). (not shown). On such a cable core A, as shown in FIG. 2A, recesses 4a are formed in a conductive or semiconductive strip 4 at regular intervals, and this is wound spirally. As shown in (b), the recesses 4a are continuously connected at a certain angle, and the metal wire B is housed in this. A metal sheath 5 made of aluminum, lead, stainless steel, etc. is provided on the strip 4, and an anti-corrosion layer 6 made of polyethylene, polyvinyl chloride, etc. is further provided on top of the metal sheath 5. Further, in the case of submarine cables, a floor, sheathing wire, and serving layer are further applied on top of the above.

In a single-core power cable, the metal sheath 5 also serves as the grounding side electrode, and it is necessary to flow the charging current due to the voltage applied between the cable conductor 1 (high voltage part) and the external shielding layer from the external shielding layer to the metal sheath. be. Therefore, it is necessary to use a conductive or semi-conductive material as the strip 4, for example, a strip made of plastic such as polyethylene, polypropylene, polybutene mixed with carbon particles or metal powder such as copper or aluminum; Alternatively, a band-shaped body made of metal such as copper, aluminum, lead, etc., or a combination thereof, etc. may be used.

The metal wire B is generally made of copper, aluminum, or an alloy thereof, and may have either one core or multiple cores, and the material and configuration of the metal wire are not particularly limited. In addition, it is impregnated with insulating oil.
In OF cables, aluminum, copper, lead, iron, stainless steel, etc. are used to protect the insulation coating (paper, plastic, etc.) of the metal wires from oil, and to protect the internal metal wires by electrically shielding them. Preferably, a metal coating is applied.

In the metal wire composite single-core power cable of the present invention having the above-described structure, by peeling off the metal sheath 5 at the end thereof, the metal wire B housed in a spiral shape can be easily taken out. ,On this occasion,
Since it will not damage cable core A in any way,
It can be connected as a power cable in the same way as before.
Extremely practical.

(Effects of the Invention) According to the above-described metal wire composite single-core power cable of the present invention, a conductive or semiconductive strip having recesses formed at a predetermined pitch is spirally wound around the cable core. By forming a recess for storing metal wires, it has excellent flexibility, and by forming the metal wires above the cable core, it is possible to take out the metal wires to the outside without impairing the performance of the power cable. , and power cable connections can be made using conventional construction methods.

Furthermore, by using a conductive or semi-conductive strip, it is possible to electrically connect the metal sheath and the outer shielding layer, allowing a charging current or a surge current to flow.

[Brief explanation of the drawing]

FIG. 1 is an explanatory diagram of a specific example of the metal wire composite single-core power cable of the present invention. FIG. 2 is an explanatory diagram of a band-like body according to the present invention, in which A is an example of the band-like body and B is an external view of the band-like body in a state in which a metal wire is inserted. FIG. 3 is a cross-sectional view of an example of a conventional metal wire composite power cable. A... Cable core, B... Metal wire, 1... Cable conductor, 3... Insulating layer, 4... Band-shaped body, 5...
...Metal sheath, 6...Anti-corrosion layer.

Claims (1)

[Scope of utility model registration request] A metal wire characterized in that a conductive or semiconductive strip having recesses formed in advance at a certain pitch is wound spirally around a cable core, and a metal wire is inserted into the continuous recesses formed. Composite single core power cable.