CN205160010U - Ground connection system that hinders falls in electric power lightning protection - Google Patents

Abstract

The utility model discloses a grounding system for electric lightning protection and resistance reduction, which comprises a lightning protection wire erected on a tower pole and a grounding wire used for grounding the above lightning protection wire. The grounding wire includes a metal hoop and connects the lightning protection wire and the metal hoop The connecting line of the ring, the metal hoop includes a ring-shaped hoop and a plurality of branch grounding wires fixed on the hoop. The utility model has the advantages of simple structure and convenient implementation, which is convenient to obtain a smaller resistivity between the lightning protection line and the earth, and can effectively reduce the lightning tripping rate of the existing power grid or reduce the possibility of the transmission line being struck by lightning.

Description

Power lightning protection and resistance reduction grounding system

technical field

The utility model relates to the field of lightning protection equipment for power transmission, in particular to a grounding system for power lightning protection and resistance reduction.

Background technique

Thundercloud discharge causes lightning overvoltage in the power system, or atmospheric overvoltage. There are two common overvoltages in overhead lines: the first is the overvoltage caused by lightning strikes near the overhead lines, and the overvoltage on the transmission line through electromagnetic induction; the second is the overvoltage caused by lightning directly hitting the lightning conductor or conductor Overvoltage. There are three specific situations: 1) lightning strikes the top of the tower; 2) lightning strikes the central part of the lightning conductor; 3) bypasses the lightning conductor and hits the conductor body. Lightning strike faults are divided into two types according to their nature: 1) Recoverable - after the lightning flashover occurs, due to the recovery of the air insulation strength, the reclosing switch is successfully put into operation; 2) Permanent - due to serious faults such as insulator falling off and wire breakage, Recloser input failed. Lightning strikes will bring different forms of damage and destruction to power facilities, as follows: 1) Overvoltage caused by lightning strikes may cause damage to insulators and transmission lines, so it will generally cause reclosing protection actions. 2) Lightning strikes will cause insulators to flashover and discharge, causing burns and falling off the porcelain surface; causing network cracks to glass insulators; causing melting marks to iron parts, etc., which will greatly reduce the insulation strength. 3) Lightning strikes on the transmission line or lightning protection line may cause broken strands or even rupture, making the power transmission work impossible. 4) When lightning strikes the concrete tower grounded through the internal iron core, the strong lightning current may cause the pole body to burst and cause the main grid to trip. The above damages may cause protective action or stop operation, so the harm is very great.

Lightning is an important factor affecting the safety of transmission lines, and has long occupied the first place in line fault tripping. Lightning is a natural process of atmospheric activity, which has not been controlled so far. But we can analyze the frequent accidents, look for the law of lightning strikes, and strengthen prevention, which can be done. The key records of being vulnerable to lightning strikes are as follows: 1) Towers located in mid-mountains or peaks of high mountains; 2) Power transmission lines near ponds and reservoirs; 3) Large-span towers, such as across mountains over 800 meters or towers of rivers and lakes; 4) Installed on towers with high grounding resistance, such as rock tower foundations and power lines. The transmission lines in the above places are still vulnerable to lightning strikes, and they are still the places where the power facilities are most damaged and the trip rate is the highest.

Utility model content

Aiming at the above-mentioned problems in the prior art that lightning strikes on transmission lines are still uncontrollable factors, and there are still some areas in the power system where the power facilities are most seriously damaged and the tripping rate is the highest, the utility model provides a A grounding system for electric lightning protection and resistance reduction.

In view of the above problems, the electric lightning protection and resistance reduction grounding system provided by the utility model achieves the purpose through the following technical points: the electric lightning protection and resistance reduction grounding system includes the lightning protection wire erected on the tower pole and the grounding for the above lightning protection wire grounding The grounding wire includes a metal hoop and a connection wire connecting the lightning protection wire and the metal hoop, and the metal hoop includes a ring-shaped hoop and a plurality of branch grounding wires fixed on the hoop.

Specifically, in the above structural form, compared with the traditional grounding wire, this structure provides a metal hoop, and the metal hoop includes a structural form of a hoop and a branch grounding wire, so that the hoop can be easily fixed on the tower pole , in this way, the connecting wire connecting the metal hoop and the lightning conductor can effectively avoid poor grounding or even grounding failure of the lightning conductor due to tensile stress due to the fixed connection points at both ends of the connecting wire during use; The structural form of multiple branch grounding wires is convenient to realize the small grounding resistance of the lightning conductor through the large contact area between the hoop, the branch grounding wires and the ground, and at the same time, the structure of the parallel connection of the branch grounding wires, compared with the traditional In the form of a grounding wire, a grounding resistance of less than 4 ohms can be obtained with less material consumption.

A further technical solution is:

As a kind of hoop structure that facilitates the connection of the hoop and the tower rod, and the connection point is convenient to be selected at the bottom end of the tapered tower rod, the hoop is in the shape of a hoop, and the hoop includes an unclosed ring hoop body and The connecting support plate is fixed on the open end of the ring hoop body, and the connecting support plate is connected by bolts.

In order to make the hoop adaptable to tower rods capable of punching a range of diameters, the hoop body is composed of multiple arc-shaped plates, and connecting support plates are provided at both ends of each arc-shaped plate.

As a structural form with good anti-corrosion ability and at the same time when the ring hoop is connected to the tower rod, the inner surface of the ring hoop and the tower rod can fit well. The arc-shaped plates are all stainless steel plates with a thickness ranging from 3mm to 5mm. Curved plate, copper plate or galvanized curved plate.

As a structural form that facilitates the fixing stability of the ring hoop and the tower rod, and at the same time increases the adaptability of the ring hoop to the diameter of the tower rod to a certain extent, the ring hoop is in the shape of a truncated cone with different diameters at both ends shape, and the inner wall surface of the ring hoop is also provided with concave and convex fine lines.

As a branch ground wire structure that is conducive to the stability of the tower pole fixed on the ground, the branch ground wires are all rigid metal conductors with arc-shaped segments, and the branch ground wires are evenly distributed in a ring shape on the hoop , the free end of the branch ground wire diverges relative to the hoop.

The utility model has the following beneficial effects:

1. Compared with the traditional grounding wire, this structure provides a metal hoop. The metal hoop includes a hoop and a branch grounding wire structure, so that the hoop can be easily fixed on the tower pole. In this way, connecting the metal hoop During the use of the connecting line between the ring and the lightning conductor, since the connection points at both ends are fixed, it can effectively avoid poor grounding or even grounding failure of the lightning conductor due to tensile stress.

2. Further, adopting the structural form of setting multiple branch grounding wires on the hoop, it is convenient to realize the small grounding resistance of the lightning conductor through the large contact area between the hoop, branch grounding wires and the ground, and at the same time, the branch grounding wires are connected to each other Compared with the traditional form of using a grounding wire, the structure form of parallel connection between them can obtain a grounding resistance value of less than 4 ohms with less material consumption.

Description of drawings

Fig. 1 is a schematic diagram of the lightning protection structure of a transmission line in the prior art;

Figure 2 is a schematic diagram of the relative position and protection angle between the lightning protection line and the transmission line in the structure of two lightning protection lines and three transmission lines in the prior art, in which a is the protection angle;

Fig. 3 is a structural schematic diagram of a specific embodiment of the electrical lightning protection and resistance-reducing grounding system described in the utility model;

Fig. 4 is a structural schematic diagram of a metal hoop in a specific embodiment of the electrical lightning protection and resistance-reducing grounding system described in the present invention.

The labels in the figure respectively represent: 1, tower pole, 2, power transmission line, 3, lightning protection line, 4, cross arm, 5, connecting line, 6, hoop, 7, branch grounding line.

detailed description

The utility model will be further described in detail below in conjunction with the examples, but the structure of the utility model is not limited to the following examples.

Example 1:

As shown in Figures 3 and 4, the electric lightning protection and resistance-reducing grounding system includes the lightning protection wire 3 erected on the tower pole 1 and the grounding wire for the above lightning protection wire 3 to be grounded. The grounding wire includes a metal hoop and a connection The connection wire 5 between the lightning conductor 3 and the metal hoop, the metal hoop includes a ring-shaped hoop 6 and a plurality of branch grounding wires 7 fixed on the hoop 6 .

Specifically, in the above structural form, compared with the traditional grounding wire, the metal hoop is provided in this structure, and the metal hoop includes the structural form of the hoop 6 and the branch grounding wire 7, so that the hoop 6 can be easily fixed on the On the tower pole 1, in this way, the connection line 5 connecting the metal hoop and the lightning protection line 3 is fixed during use due to the fixed connection points at both ends, which can effectively avoid poor grounding or even grounding failure of the lightning protection line 3 due to tensile stress; further , adopting the structural form of setting multiple branch grounding wires 7 on the hoop 6, it is convenient to realize the small grounding resistance of the lightning conductor 3 through the large contact area between the hoop 6, the branch grounding wires 7 and the ground, and at the same time the branch grounding wires 7 The structural form connected in parallel with each other, compared with the traditional form of using a grounding wire, can obtain a grounding resistance value of less than 4 ohms with less material consumption. In this embodiment, the connecting wire 5 The upper end of the upper end is connected to the cross arm 4 located at the tower pole 1, and the lower end of the connecting wire 5 is fixed to the hoop 6 to realize the structural form. The above structural form is convenient to avoid the tensile stress generated on the connecting wire 5 during use of the utility model.

Example 2:

As shown in Fig. 3 and Fig. 4, this embodiment is further limited on the basis of embodiment 1: as a method that facilitates the connection of the hoop 6 to the tower rod 1, and the connection point is convenient to be selected at the bottom end of the tapered tower rod 1 The hoop 6 has a structural form, the hoop 6 is in the shape of a hoop, and the hoop 6 includes an open ring hoop body and a connecting support plate fixed at the opening end of the ring hoop body, and the connecting support plate is connected by bolts.

In order to make the hoop 6 adaptable to the tower rod 1 that can drill a range of diameters, the hoop body is composed of multiple arc-shaped plates, and each end of the arc-shaped plate is provided with a connecting support plate.

As a structural form with good anti-corrosion ability and at the same time when the hoop 6 is connected to the tower rod 1, the inner surface of the ring hoop and the tower rod 1 can fit well, and the thickness of the arc-shaped plates is between 3mm and 5mm. Stainless steel plate curved plate, copper plate or galvanized curved plate.

As a structural form that is convenient for consolidating the fixing stability of the ring hoop and the tower rod 1, and at the same time can increase the adaptability range of the ring hoop to the diameter of the tower rod 1 to a certain extent, the ring hoop is in the form of a ring with different diameters at both ends. It is in the shape of a truncated cone, and the inner wall surface of the ring hoop is also provided with concave and convex fine lines.

As a branch ground wire structural form that is beneficial to the stability of the tower pole 1 fixed on the ground, the branch ground wires 7 are all rigid metal conductors with arc-shaped segments, and the branch ground wires 7 are formed on the hoop 6 The rings are evenly distributed, and the free ends of the branch grounding wires 7 are divergent relative to the hoop 6 .

Example 3:

The utility model also provides a specific form of a specific power lightning protection and resistance reduction grounding system. This embodiment is aimed at a three-phase transmission line 2 with a voltage of 20kV, a tower pole 1 with a height of 20 meters, three lightning protection lines 3 arranged in parallel with three Above the transmission line 2, the distance between the connected lightning protection line 3 is 5.5 meters, the vertical height between the lightning protection line 3 and the transmission line 2 is 5.5 meters, the distance between the transmission line 2 is 5 meters, and the middle transmission line 2 is located in the middle directly below the lightning conductor 3.

At the same time, this embodiment discloses a specific structure of a metal hoop, wherein the branch ground wires 7 are formed by bending one end of a copper rod with a diameter of 20 mm and a length of 800-1000 mm, and the bent side of the above copper rod is a free end. The other end of the copper rod is fixed on the hoop 6, the free end of the copper rod diverges outward relative to the hoop 6, and the free end of the copper rod protrudes 300 mm relative to the hoop 6, and the hoop 6 and the connecting support plate They are all made of stainless steel plates with a thickness of 5mm, and the hoop 6 is an unclosed ring structure; in order to adapt to the existing widely used cement tower rod 1, or the cement base of the iron tower, the inner diameter of the hoop 6 is 400mm , the height is 80mm, and the open end of hoop 6 is a 40mm wide opening, the side length of the connecting support plate is 80mm*50mm, and the connecting support plate is connected by stainless steel bolts with a diameter of 10mm.

The above content is a further detailed description of the utility model in combination with specific preferred embodiments, and it cannot be determined that the specific embodiments of the utility model are only limited to these descriptions. For those of ordinary skill in the technical field to which the utility model belongs, other implementation modes obtained without departing from the technical solution of the utility model shall be included in the protection scope of the utility model.

Claims (6)

1. electric power lightning protection electric resistance reducing grounding system, comprise and be set up in the lightning conducter (3) on tower bar (1) and the earth connection for above lightning conducter (3) ground connection, it is characterized in that, described earth connection comprises metal hoop and connects the connecting line (5) of lightning conducter (3) and metal hoop, Duo Gen branch earth connection (7) that described metal hoop comprises hoop (6) in the form of a ring and is fixed on hoop (6).

2. electric power lightning protection electric resistance reducing grounding system according to claim 1, it is characterized in that, described hoop (6) is in anchor ear shape, and described hoop (6) comprises inc annular hoop body and is fixed on the connection support plate of annular hoop body openend, and described connection is propped up crab bolt and connected.

3. electric power lightning protection electric resistance reducing grounding system according to claim 2, it is characterized in that, described annular hoop body is made up of multistage arc, and the two ends of every section of arc are provided with connection support plate.

4. electric power lightning protection electric resistance reducing grounding system according to claim 3, is characterized in that, described arc is thickness between the stainless-steel sheet arc of 3mm to 5mm, copper coin or zinc-plated arc.

5. electric power lightning protection electric resistance reducing grounding system according to claim 2, is characterized in that, the circular cone shape that described hoop (6) does not wait in two ends diameter, and the internal face of hoop (6) is also provided with concavo-convex microgroove.

6. electric power lightning protection electric resistance reducing grounding system according to claim 1, it is characterized in that, described branch earth connection (7) is the rigid metal conductor being provided with segmental arc, and branch's earth connection (7) is uniform in the form of a ring on hoop (6), the free end of branch's earth connection (7) relative to hoop (6) in divergent shape.