RU177298U1 - Cable resistance of a double-chain support of an overhead power line - Google Patents

Abstract

The proposal relates to the construction of overhead power transmission lines (OHL) and can be used in the design and manufacture of cable racks mainly for intermediate supports of double-circuit overhead lines. The technical result of the utility model is to reduce the cost and labor costs of installing lightning protection for double-circuit overhead lines. On the rack 1 of the overhead support in three tiers, two-console traverses 2 (lower), 3 (middle) and 4 (upper), designed for insulating suspension of six phase wires 11 of a double-circuit overhead line. Above the upper traverse 4 on the rack 1, the proposed V-shaped cable rack is fixed 5. On the consoles 6 and 7 of the cable rack 5, with the help of insulating suspensions 8 and 9, a ground wire is fixed 10. The distances from the cable 10 to the consoles 6 and 7 are equal to or greater than the insulation distances to the grounded parts supports normalized for the used ice melting stress. The suspension height of the ground wire 10 provides for any of the six phase conductors 11 an angle of lightning protection, the maximum value of which (30 °) is normalized by the current version of the "Rules for Electrical Installations" (ПУЭ-7). 1 ill.

Description

Technical field

The utility model relates to the construction of overhead power lines (OHL) and can find application in the design and manufacture of predominantly intermediate lattice supports for double-circuit OHL.

State of the art

At present, in single-column supports of double-circuit overhead lines (in double-chain supports) of the 35-330 kV class, two-wire cable-racks are used for suspension of two lightning protection cables (lightning cables) on intermediate supports and non-console cable-racks for the suspension of one lightning cable in anchor supports ("Unified steel normal supports of VL 220 and 330 kV ”, series 3.407-100, All-Union State Design and Research and Scientific Research Institute“ Energetsetproekt ”, Moscow, 1973 [1]).

Cable racks allow you to suspend lightning ropes so as to provide:

- normalized ПУЭ-7 lightning protection angle for all phase conductors of both circuits;

- the possibility of melting ice due to compliance with insulating distances (to the grounded parts of the support), normalized to the voltage used when melting ice formation on a lightning protection cable.

The need to use two ground wires on a double-circuit overhead line to fulfill these requirements is a disadvantage of the well-known double-conductor cables.

As a prototype of the inventive cable resistance, the console-free cable resistance of standardized anchor supports (for example, type U220-2), designed to suspend a single lightning cable that meets both of the above requirements, is considered. At the same time, the span sections of the ground wire are attached to the cable rack on the axis of symmetry of the support using insulating suspensions and are connected by an insulated cable to bypass the cable rack. The disadvantage of the prototype solution is the increased cost of lightning protection of overhead lines due to the use of insulating loops and greater labor costs for installation, which is why the prototype solution is not used in practice in intermediate double-circuit supports mass-mounted on overhead lines.

Utility Model Disclosure

The technical result of the utility model in relation to the prototype is to reduce the cost and labor costs of installing lightning protection double-circuit overhead lines.

The subject of a utility model is a cable rack of a double-circuit VL support, containing means for insulating the suspension of a single lightning protection cable over the OHL phase wires, characterized in that the said tool is made in the form of two consoles mounted V-shaped with the possibility of insulating suspension between them of a lightning protection cable at a height sufficient to ensure a normalized angle of lightning protection of the phase conductors of both circuits, and at insulating distances from the cable, normalized for the voltage of melting ice on lightning protection cable.

This allows you to get the above technical result.

The implementation of the utility model The figure shows a diagram of a two-chain intermediate support equipped with the proposed V-shaped cable-resistant.

The support diagram shows a rack 1, on which two-console traverses 2 (lower), 3 (middle) and 4 (upper) are fixed in three tiers for insulating suspension of six phase wires of a double-circuit overhead line. Above the upper traverse 4 on the rack 1, the proposed cable rack 5 is fixed with V-shaped consoles 6 and 7. On the consoles 6 and 7 of the cable rack 5, with the help of insulating suspensions 8 and 9, a lightning protection cable 10 is suspended.

The lengths of the consoles 6 and 7 and the angle between them are selected so that the distances from the cable 10 to the consoles 6 and 7 are equal to or greater than the insulating distances to the grounded parts of the support, normalized by the current edition of the Electrical Installation Rules (PUE-7) for the used ice melting voltage and the suspension height of the ground wire 10 provides for any of the six phase conductors 11 of the two circuits В Л the angle of lightning protection, the maximum value of which (30 °) is normalized by ПУЭ-7.

Thus, the above-described V-shape of a lightning-proof one allowed to hang a single lightning rod 10 symmetrically with respect to both circuits of a double-circuit overhead line at a height sufficient to provide the required PUE-7 lightning protection angle for phase wires of both overhead lines, and at normalized insulation distances to the grounded parts of the support (consoles cable-resistant) without the need to cut the ground wire into spans and connect them with insulated cables.

The use of the inventive cable resistance on the intermediate supports of a double-circuit overhead line will provide its lightning protection with one lightning cable with the possibility of melting ice on it.

Claims (1)

Cable-resistant double-chain support of an overhead power transmission line containing means for insulating suspension of a single lightning protection cable over the phase conductors of an overhead power transmission line, characterized in that said means is made in the form of two consoles mounted V-shaped with the possibility of insulating suspension between them of a lightning protection cable at a height sufficient to ensure a normalized angle of lightning protection for phase conductors of both circuits, and at insulating distances from the cable, normalized for zheniya ice melting on the ground wire.

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