±500kv trapezoidal wire conductor copper wire shielded fiber optic composite DC cable

Abstract

The invention discloses a ±500kV trapezoidal wire conductor copper wire shielded optical fiber composite direct current cable, which comprises a large cross-section trapezoidal wire conductor, a conductor shielding layer, an insulating layer, an insulating shielding layer, a first semiconducting resistance water buffer layer, and an optical fiber unit , copper wire composite copper tape shielding layer, the second semiconductive resistance water buffer layer, aluminum-plastic composite tape, insulating outer sheath and semiconductive layer; The monofilament is layered and stranded. According to the requirements of different conductor cross-sections, the outer layer of trapezoidal copper monofilament adopts a round copper single wire or a circular core formed by tightly twisting multiple round single wires. 1 ‑6 layers of SZ-shaped copper monofilaments. The present invention adopts a trapezoidal wire conductor with a large cross-section, the conductor structure is stable and compact, and the filling factor is not less than 93%. Under the same current-carrying capacity, the conductor diameter is smaller than that of a compact circular conductor or a segmented conductor, which greatly saves The overall cost input of the cable.

Description

technical field [0001] The invention relates to a cable, in particular to a large cross-section trapezoidal wire conductor copper wire shielding type optical fiber composite DC cable with a voltage level of ±500kV. The invention belongs to the technical field of cable manufacturing. Background technique [0002] Flexible DC transmission technology has attracted widespread attention due to its low line cost, small line loss, stable system, flexible control of active power and reactive power, reliable operation, convenient phased construction and capacity expansion. It is widely used in island power transmission and urban power distribution. It has been widely used in fields such as network expansion and transformation, AC system interconnection, and large-scale wind farm grid connection. [0003] Flexible DC cable is one of the key equipment of flexible DC transmission technology. Flexible DC transmission avoids the skin effect and proximity effect in the process of AC transm...

AI Technical Summary

Problems solved by technology

But when the conductor section exceeds 2000mm 2 , limited by the maximum number of single wires that can be completed by current conductor stranding equipment, to further increase the cross-section can only rely on increasing the diameter of the single wire, which easily leads to the disadvantages of large gaps and small compression coefficients of the single wires. Subsequent insulation extrusion production will bring more difficulty, and the larger conductor outer diameter will increase the overall cost of the cable, so it is necessary to develop a new structure of large cross-section water-blocking conductors to adapt to higher transmission capacity and higher voltage level flexibility DC transmission needs

[0004] The main application range of AC-DC high-voltage power cables is concentrated in the field of power transmission. Affected by cable structure, manufacturing process and equipment capabilities, unlike high-voltage submarine cables, AC-DC high-voltage power cables used in land-based high-voltage transmission lines currently have few optical fibers. Composite products are put into application. In traditional land transmission lines, optical cables and cables are separated to complete communication transmission or monitor cables, which brings disadvantages in terms of product cost, engineering difficulty and monitoring effect.

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