CN203632182U - Lightning protection device of 20kV overhead line - Google Patents

Abstract

A lightning protection device for a 20kV overhead line, the 20kV overhead line includes a 20kV trunk line using 185mm ² and 240mm ² insulated wires and a 20kV branch line wire using 70mm ² -120mm ² insulated wires, erected on the 20kV trunk line The overhead lightning protection line composed of coupled ground wires is equipped with 20kV lightning arresters on both sides of the equipment on the 20kV main line; on the main line of the 20kV overhead line, each base pole is equipped with a grounding device, The grounding resistance is not greater than 10Ω; the 20kV branch line conductor is equipped with a zinc oxide arrester with gaps and a coincident circuit breaker; wherein the coincident circuit breaker is installed on the opening side of the large branch line; it has a simple structure, is easy to use and install, and can Effectively reduce lightning shock wave and induced lightning overvoltage, and reduce the probability of line lightning failure.

Description

A Lightning Protection Device for 20kV Overhead Line

technical field

The utility model relates to a lightning protection device specially for 20kV overhead lines, which belongs to the technical field of lightning protection for 20kV distribution network. the

Background technique

Compared with 10kV lines, 20kV lines have obvious advantages such as stronger line power supply capacity, larger power supply radius and power supply range, saving construction investment, and saving land materials. Although the 20kV voltage line has many advantages, there are still many difficulties and problems in the operation of the completed 20kV grid. For example, bird damage and lightning damage are the main reasons that affect the safe operation of the 20kV grid. At present, the commonly used lightning protection measures on the overhead lines of the distribution network are as follows: using zinc oxide arresters, placing arc-proof hardware, installing zinc oxide arresters with gaps, and using lightning protection insulators, etc. These lightning protection measures are used in actual use. , there are one or another deficiency, especially in the new voltage level of the distribution network - the application of 20kV voltage overhead lines. Since the lightning protection of 20kV overhead lines is mainly to prevent line equipment failure after lightning overvoltage, such as lightning breakage of overhead insulated conductors, damage to user equipment, secondary disasters, etc., and affect the upper-level power grid. At present, the lightning protection measures usually taken to prevent lightning overvoltage from affecting the power grid at the upper level are: setting up automatic reclosing in the substation and setting up lightning arresters outside the substation to cooperate; difficulty. the

Contents of the invention

The purpose of the utility model is to overcome the deficiencies in the prior art, and provide a lightning protection device for 20kV overhead lines with simple structure, convenient use and installation, which can effectively reduce the lightning shock wave and induced lightning overvoltage, and reduce the probability of line lightning failure. . the

The purpose of this utility model is accomplished through the following technical solutions. The 20kV overhead line includes 20kV trunk lines using 185mm ² and 240mm ² insulated wires and 20kV branch wires using 70mm ² -120mm ² insulated wires. An overhead lightning protection line composed of coupled ground wires is erected on the main line, and 20kV lightning arresters are installed on both sides of the equipment on the 20kV main line.

On the main line of the 20kV overhead line, each base pole is equipped with a grounding device, and the grounding resistance is not greater than 10Ω. the

Zinc oxide surge arresters with gaps and coincident circuit breakers are installed on the 20kV branch line conductors; wherein the coincident circuit breakers are installed on the opening side of the large branch line. the

The equipment described includes the load opening on the column and the cable crossing; above or below the insulated conductors, an overhead coupling ground wire that shields the three-phase conductors is erected. the

The utility model is to set up an overhead (coupling) ground wire above or below the insulated wire under the condition of ensuring a safe distance, so that it can shield the three-phase wires, and through the segmental grounding of the induction lightning protection wire, And it is very close to the insulated wire, so that the electromagnetic field near the insulated wire changes. When lightning strikes the line, the induced lightning voltage on the insulated wire is significantly reduced, thereby reducing the lightning flashover probability of the line and the lightning disconnection rate of the insulated wire. the

The utility model can effectively reduce the lightning shock wave and the induced lightning overvoltage, and reduce the probability of lightning strike failure of the line; it has good economy and light cost, especially the cost of installing lightning protection wires in double circuits and above is much lighter than that of installing lightning protection fittings, and Does not damage the surface structure of the wire; each base pole is effectively grounded, and a grounding grid is formed through the lightning protection line to reduce the grounding resistance and effectively lead the lightning into the ground; it has a simple structure, is easy to use and install, and can effectively reduce the shock wave of lightning. It has the characteristics of inducting lightning overvoltage and reducing the probability of line lightning failure. the

Description of drawings

Fig. 1 is the structural representation of the utility model. the

Detailed ways

The utility model will be described in detail below in conjunction with the accompanying drawings: As shown in Figure 1, the 20kV overhead line described in the utility model comprises the 20kV trunk line 1 that adopts 185mm ² and 240mm ² insulated conductors and adopts 70mm ² -120mm ² insulated conductors The 20kV branch line conductor, the overhead lightning protection line 2 composed of the coupled ground wire 3 is erected on the 20kV main line 1, and the equipment (such as: the load opening on the column, the cable crossing) is installed on both sides of the 20kV main line 1. 20kV arrester.

On the main line 1 of the 20kV overhead line, each base pole is equipped with a grounding device, and the grounding resistance is not greater than 10Ω. the

Zinc oxide surge arresters with gaps and coincident circuit breakers are installed on the 20kV branch line conductors; wherein the coincident circuit breakers are installed on the opening side of the large branch line. the

The described equipment includes the load opening on the column and the cable crossing; above or below the insulated conductors, an overhead coupling ground wire 3 that shields the three-phase conductors is erected. the

Although the 20kV line has many advantages, it also has certain limitations, such as the difficulty of transformation, the grounding method is not perfect, etc., which has a certain impact on the lightning protection of the 20kV line. the

    With the popularization and application of 20kV distribution network, the manufacturing technology of its equipment will get great development. The safe and healthy operation of the grid will receive more and more attention; the utility model provides a stronger guarantee for the high-quality, safe and reliable operation of the 20kV grid.

Claims (4)

1. A lightning protection device for 20kV overhead lines, said 20kV overhead lines comprise 20kV trunk lines adopting 185mm ² , 240mm ² insulated wires and 20kV branch wires adopting 70mm ² -120mm ² insulated wires, characterized in that: The 20kV main line is erected with an overhead lightning protection line composed of coupled ground wires, and 20kV lightning arresters are installed on both sides of the equipment on the 20kV main line. 2. The lightning protection device for 20kV overhead lines according to claim 1, characterized in that on the trunk line of the 20kV overhead lines, each base pole is equipped with a grounding device, and the grounding resistance is not greater than 10Ω. 3. The lightning protection device for 20kV overhead lines according to claim 1, characterized in that the 20kV branch wires are equipped with zinc oxide arresters with gaps and coincident circuit breakers; wherein the coincident circuit breakers are installed on large branch lines the beginning side of the 4. The lightning protection device for 20kV overhead lines according to claim 1, characterized in that said equipment includes load openings on the pole and cable crossing; above or below the insulated wires, there is a shielding device for the three-phase wires. The role of the overhead coupling ground.

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