+/-500kV SZ-shaped molded line conductor corrugated aluminum sheath fiber composite DC cable

Abstract

The invention discloses a + / -500kV SZ-shaped molded line conductor corrugated aluminum sheath fiber composite DC cable, and the cable comprises a large-section SZ-shaped molded line conductor, a conductor shielding layer, an insulating layer, an insulating shielding layer, a fiber unit, a metal reinforcing core, a semiconductive waterproof buffering layer, a corrugated aluminum sheath, an insulating external protection layer, and a semiconductive layer. The large-section SZ-shaped molded line conductor is formed by the layered intertwisting of a central cable core and an outer SZ-shaped copper filament. The outer SZ-shaped copper filament employs one circular copper wire or an SZ-shaped copper filament which is formed by the compression intertwisting of a plurality of circular filaments, wherein the exterior of the circular cable core is intertwisted with 1-6 layers. The cable employs the large-section SZ-shaped molded line conductor, and is stable and compact in conductor structure. The filling coefficient is not less than 93%. Compared with a compression circular conductor or a segmented conductor under the same current-bearing capability, the cable is smaller in conductor diameter, and greatly saves the overall cost of the cable.

Description

technical field [0001] The invention relates to a cable, in particular to an optical fiber composite DC cable with a large cross-section SZ-shaped wire conductor wrinkled aluminum sleeve and 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 tra...

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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