CN107700926A - A kind of double loop cable termination tower - Google Patents

Abstract

The invention relates to a double-circuit cable terminal tower. The cable terminal tower includes a tower body support, and the tower body support is sequentially provided with an upper phase cross arm, a middle phase cross arm and a lower conductor cross arm from top to bottom. The upper phase cross arm is a T-shaped cross arm, and the two sides of the middle phase cross arm are respectively provided with extension parts, and the T-shaped cross arm and the extension part of the middle phase cross arm are respectively provided with wire guide hanging point devices. Compared with the prior art, the invention has the advantages of reducing the impact of the cable terminal tower on the surrounding environment, simple structure, space saving and the like.

Description

A double-circuit cable terminal tower

technical field

The invention relates to a cable terminal tower, in particular to a double-circuit cable terminal tower.

Background technique

Study the characteristics and trends of power grid planning at home and abroad. With the rapid development of my country's economy, the scale of cities continues to expand, and electricity consumption increases day by day. When the power grid continues to expand, land resources are becoming increasingly tight, especially in large and medium-sized cities. The cost of land acquisition is getting higher and higher. At the same time, people's requirements for the environment are also constantly improving. Compared with the previous overhead lines, cables have high power supply reliability, and the wiring is not affected by buildings in the ground space, which is conducive to beautifying the city and optimizing the layout of factories and mines, and has little electromagnetic interference to the environment, which is relatively safe for people and relatively small maintenance costs And many other advantages, so it has been widely promoted and applied.

However, due to the relatively large investment in cables and the high requirements for underground space resources, cables have not completely replaced overhead lines in the current grid construction. Some lines still retain some overhead lines in consideration of cost when they are transformed into cables. Based on the above reasons, there are more and more cable overhead hybrid lines in urban power grids, and at the junction of overhead lines and cable lines, corresponding electrical equipment is required to connect them. At the same time, environmental factors and other issues need to be considered in the construction of cable terminal towers in cities.

Contents of the invention

The object of the present invention is to provide a double-circuit cable terminal tower in order to overcome the above-mentioned defects in the prior art.

The purpose of the present invention can be achieved through the following technical solutions:

A double-circuit cable terminal tower, the cable terminal tower includes a tower body support, and the tower body support is provided with an upper phase cross arm, a middle phase cross arm and a lower conductor cross arm in sequence from top to bottom, and the upper phase cross arm The arm is a T-shaped cross-arm arranged horizontally, extensions are respectively provided on both sides of the middle-phase cross-arm, and the extensions of the middle-phase cross-arm and the T-shaped cross-arm are respectively provided with wire guide hanging points.

Preferably, a cable platform is provided on the cross-arm of the down conductor, a protective fence is provided around the cable platform, and supporting insulators, lightning arresters and outdoor terminals are installed on the cable platform.

Preferably, the support insulator, the lightning arrester and the outdoor terminal are all covered with composite sleeves.

Preferably, tension insulators are respectively provided on the upper phase cross arm, middle phase cross arm and lower conductor cross arm, and the tension insulators are connected to the conductors.

Preferably, suspension lightning rods are sequentially connected between the upper phase cross arm and the middle phase cross arm and between the middle phase cross arm and the lower conductor cross arm.

Preferably, the two ends of the intermediate phase cross arm are respectively provided with corner brackets on the same side.

Preferably, the bottom stabilizing device of the tower body support adopts a single pile cast-in-situ pile.

Preferably, foot bars are arranged around the tower body bracket.

Compared with the prior art, the present invention has the following advantages:

1. Reduce the impact of the cable terminal tower on the surrounding environment: add T-shaped cross-arms to realize three-phase independent grounding, simple structure, small size, convenient down-leading method, and easy implementation. The tensile insulation on the conductor cross-arm reduces the support structure and supports the insulators , Lightning arresters and outdoor terminals are equipped with composite casings, which can effectively reduce the impact of electrical equipment failures on the surroundings;

2. The structure is simple and space-saving: the two ends of the middle-phase cross-arm are respectively provided with corner frames on the same side, which effectively reduces the supporting structure and is suitable for areas with tight land areas;

3. There is a protective fence around the cable platform: to prevent the surrounding environment from affecting the tower support;

4. The overall height of the tower is reduced, the occupied area is reduced, the applicability is improved, and the requirements for the target line are lowered.

Description of drawings

Fig. 1 is a three-dimensional single-line diagram of the present invention;

Fig. 2 is the front view of the present invention;

Figure 3 is a side view of the invention.

detailed description

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

Example

The 220kV double-circuit terminal tower is a special tower that realizes the transformation of 220kV overhead lines into cable lines. The terminal tower is mainly divided into 5 parts, namely: tower head form, lead-in form, terminal platform, cable support system and cable laying and fixing.

On the tower head, the 220kV terminal tower must meet the electrical clearance requirements of the 220kV overhead line to the tower head, and the distance between the conductor and ground wires must meet the requirements for lightning protection. On this basis, structural changes can be made. Based on the improvement of the 220kV double-circuit tower head based on the ordinary 220kV double-circuit strain tower, a new T-connected cross arm is built on the side of the upper phase behind the line, which is used as the jumper hanging point of the upper phase; the middle phase cross arm is picked out Extended, as the hanging point of the middle conductor; the cross arm of the lower conductor is not processed.

A double-circuit cable terminal tower, as shown in Figure 1, Figure 2 and Figure 3, the specific structure is that the cable terminal tower includes a tower body support, and the tower body support is sequentially provided with an upper phase cross arm and a middle phase cross arm from top to bottom. The upper phase cross arm is a T-shaped cross arm, and the two sides of the middle phase cross arm are respectively equipped with extension parts, and the T-shaped cross arm and the extension part of the middle phase cross arm are respectively equipped with a wire guiding lower hanging point device . A cable platform is set at the cross arm of the lower conductor, and a protective fence is provided around the cable platform. Supporting insulators, lightning arresters and outdoor terminals are installed on the cable platform. Composite bushings are installed on support insulators, lightning arresters and outdoor terminals. Tension insulators are respectively arranged on the upper phase cross arm, the middle phase cross arm and the lower conductor cross arm. Suspension lightning rods are sequentially connected between the upper phase cross arm and the middle phase cross arm and between the middle phase cross arm and the lower conductor cross arm. The two ends of the middle phase cross arm are respectively provided with corner frames on the same side. The bottom stabilization device of the tower body bracket adopts single pile cast-in-place pile. Foot rods are arranged around the tower body bracket.

In terms of the form of lead-through, the system capacity must first be analyzed, and the selection of the cable cross-section should be reasonably coordinated on the basis of satisfying the capacity. For example, considering the cutover of the line vision, 2×JL/LB1A-630/45 is used. If the maximum capacity of the system is only 300MVA, a cable of 1×1000mm ² can meet the requirements, so a single 630/45 can be used for the lead wire. The lead-in of the wire is divided into a direct lead-in type and an indirect lead-in type. The conductor adopts JB-6 parallel groove clamp to fix the double-split conductor, so as to reduce the equivalent radius of the double-split conductor, and fully increase the phase-phase and phase-ground without increasing the form of tower head and down-lead. distance.

The terminal platform, that is, the cable platform, is the carrier of the overhead line to the cable. The first requirement is the bearing force, followed by the layout of the equipment determines the size of the platform, and the third is the difficulty of cable laying and later operation and maintenance determined by the height of the platform. The platform is symmetrically arranged, and arresters, composite insulators, and outdoor terminals are arranged in sequence from the tower body outward.

The cable support system is the carrier to realize and improve the safe operation of cables. The stability of the bracket system also determines the stress at the connection between the cable and the terminal. Cable laying and fixing are realized based on the support system, and the difficulty of laying depends on the height of the platform and the arrangement position of the support (cross arm). The cable support adopts "upright", vertical cable support system, the support adopts independent foundation, and the support is fixed with 2 to 3 cross-arms to fully stabilize the cable support and prevent the uneven settlement of the independent support from causing outdoor terminals and cables. Electrical barriers at the connection face.

Set up two symmetrically arranged equipment platforms at a distance of about 9m from the ground at the 220kV terminal tower. On the platforms, overhead and electrical equipment for cable conversion (supporting insulators, lightning arresters, outdoor terminals, etc.) are arranged and test openings are reserved. The upper phase wire is picked out in the opposite direction to the line through the branch cross arm, the wire is pulled against the supporting insulator on the platform through the insulator, and the wire T is connected to the outdoor terminal and the arrester through the T-shaped clamp; The direction of the gear is lengthened, the wire is pulled opposite to the supporting insulator on the platform through the insulator, and the wire is connected to the outdoor terminal and the lightning arrester through a T-shaped clamp; the length of the cross arm of the lower phase wire meets the requirements, and the wire passes through the insulator and the supporting insulator on the platform Pull the wires to each other, and then connect the wires to the outdoor terminal and the arrester through the T-shaped clamp, so as to realize the conversion of the three-phase wires into cable lines.

On this basis, the electrical equipment on the terminal tower is made of composite casing materials, which fully guarantees the safety of the equipment and minimizes the impact of the equipment on the surrounding environment.

The perimeter of the terminal tower is surrounded by a hollow fence, and technical defense facilities such as electric fences are installed on the fence to fully guarantee the safety and reliability of the terminal tower.

The above is only a specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any person familiar with the technical field can easily think of various equivalents within the technical scope disclosed in the present invention. Modifications or replacements shall all fall within the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims (8)

1. A double-circuit cable terminal tower, characterized in that the cable terminal tower includes a tower body support, and the tower body support is successively provided with an upper phase cross arm, a middle phase cross arm and a lower conductor cross arm from top to bottom, The upper-phase cross-arm is a T-shaped cross-arm arranged horizontally, extensions are respectively provided on both sides of the middle-phase cross-arm, and wire guides are respectively provided on the extensions of the middle-phase cross-arm and the T-shaped cross-arm. Lower hanging point. 2. A double-circuit cable terminal tower according to claim 1, wherein a cable platform is arranged on the cross arm of the lower conductor, and a protective fence is provided around the cable platform, and a protective fence is installed on the cable platform. Support insulators, surge arresters and outdoor terminations. 3. A double-circuit cable terminal tower according to claim 2, characterized in that, said supporting insulators, lightning arresters and outdoor terminals are all provided with composite sleeves. 4. A kind of double-circuit cable terminal tower according to claim 1, characterized in that, said upper phase cross arm, middle phase cross arm and lower conductor cross arm are provided with tension insulators respectively, and said strain resistance The insulator is connected to the wire. 5. A kind of double-circuit cable terminal tower according to claim 1, characterized in that, there are sequentially connected between the upper phase cross arm and the middle phase cross arm and between the middle phase cross arm and the lower conductor cross arm Suspension lightning rod. 6. The double-circuit cable terminal tower according to claim 1, wherein the two ends of the intermediate phase cross arm are respectively provided with corner brackets on the same side. 7. A double-circuit cable terminal tower according to claim 1, characterized in that, the bottom stabilizing device of the tower body bracket adopts a single pile cast-in-place pile. 8. A double-circuit cable terminal tower according to claim 1, characterized in that foot bars are arranged around the tower body support.