CN204464915U - Transmission line of alternation current steel tower - Google Patents

Abstract

The utility model discloses an iron tower of an AC transmission line, which comprises a tower body and a cross arm at the top of the tower. Lightning protection insulators are respectively connected to the two ends and the middle part of the lower side of the cross arm, and the lower ends of the lightning protection insulators at both ends are respectively connected to side phase conductors. 1. The lower end of the lightning protection insulator in the middle is connected to the middle-phase conductor, and a composite optical fiber overhead ground wire is installed at the waist of the tower body. The lightning protection insulator suspends the wire so that it has the functions of suspension, insulation and lightning protection at the same time. When the lightning strikes the tower or the wire directly, the lightning overvoltage will make the lightning protection insulator move, absorb the impact energy, and play a role in overvoltage Clamping is used to protect the entire insulator from flashover, avoid tripping of transmission lines, and improve power supply reliability. The composite optical fiber overhead ground wire is located under the three-phase wire, which can not only realize the normal power communication function, but also reduce the lightning overvoltage on the lightning protection insulator due to the coupling effect, further improve the lightning resistance level, and effectively reduce the number of lightning trips on the transmission line. Improve power supply reliability.

Description

AC transmission line tower

technical field

The utility model relates to an iron tower of an AC transmission line, in particular to a lightning protection structure of an iron tower of an AC transmission line.

Background technique

The power grid covers a wide area, and many transmission lines have to pass through areas where lightning is frequent. When encountering thunderstorms, lightning flashovers are likely to occur on transmission lines and cause trip accidents. Statistics show that the number of lightning trips on transmission lines exceeds 50% of the total trips, which is the biggest threat to the safe operation of the power grid.

For lightning protection of transmission lines, the most commonly used method is to install overhead ground wires on iron towers. Its main function is to protect the wires below from being directly struck by lightning. The overhead ground wire needs to be installed on the dedicated ground wire bracket at the top of the tower. The ground wire support not only needs to consume tower materials, but also may break and damage the ground wire support in some cold regions due to the severe ice coating of the overhead ground wire in winter and is difficult to remove, resulting in power supply interruption.

In recent years, the lightning protection method of installing line arresters in parallel with insulators on transmission line towers has also emerged. However, adding new line arresters requires adding new fixing devices to the original towers, and the existing line arresters are long in size and cannot meet the requirements of the tower window. It has the disadvantages of difficulty in erection and high investment cost.

Utility model content

The purpose of the utility model is to provide an iron tower structure that can not only ensure the lightning protection effect of the transmission line, thereby improving the reliability of power supply, but also reduce the construction investment of the transmission line.

The utility model discloses an iron tower of an AC transmission line, which comprises a tower body and a cross arm at the top of the tower body. The tower body is equipped with a composite optical fiber overhead ground wire, and the two ends of the lower side of the cross arm and the middle part are respectively connected with lightning protection insulators. The lower ends of the lightning protection insulators at both ends are respectively connected to the side phase conductors, and the lower ends of the lightning protection insulators in the middle are connected to the middle phase conductors.

The composite optical fiber overhead ground wire is installed at the waist of the tower body.

The utility model uses the lightning protection insulator to suspend the wire, so that it has the functions of suspension, insulation and lightning protection at the same time. When the lightning falls directly on the pole tower or the wire, the lightning overvoltage will make the lightning protection insulator act and absorb the impact energy. It plays a clamping role on overvoltage, thereby protecting the entire insulator from flashover, avoiding tripping accidents of transmission lines, and improving power supply reliability. The composite optical fiber overhead ground wire is directly installed at the waist of the tower body, located below the three-phase wire, which can not only realize the normal power communication function, but also reduce the lightning overvoltage on the lightning protection insulator due to the coupling effect, and further improve the lightning resistance level , effectively reduce the number of lightning trips on the transmission line, and improve the reliability of power supply.

The composite optical fiber overhead ground wire is directly installed at the waist of the iron tower body, canceling the ground wire support and a common overhead ground wire at the top of the existing technology tower, saving material and manpower, and eliminating the need for two overhead ground wires in the prior art. Loop loss; the mechanical strength of the tower body is much greater than the strength of the ground wire support, which greatly improves the ice resistance of the composite optical fiber overhead ground wire, thereby improving the ice resistance of the transmission line as a whole and further improving the reliability of power supply. The installation position of the composite optical fiber overhead ground wire is also convenient for maintenance.

Description of drawings

Fig. 1 is a structural schematic diagram of an embodiment of the utility model.

Detailed ways

As shown in Fig. 1, the utility model discloses an iron tower of an AC transmission line, which includes a tower body 1 and a cross arm 2 at the top thereof. The lower end of the lightning protection insulator 3 at the end is respectively connected to the side phase conductor 4, the lower end of the lightning protection insulator 3 in the middle is connected to the middle phase conductor 5, and a composite optical fiber overhead ground wire 6 is installed at the waist of the tower body 1.

When making the iron tower, the tower body and the cross arm can be purchased, such as the tower material produced by Hunan Dali Steel Structure Manufacturing Company in China. Lightning protection insulators can be purchased, such as AC lightning protection insulators produced by Xiangdian Trial Technology Co., Ltd. in Hunan Province, China. The three-phase wires can be steel-cored aluminum stranded wires produced by China Jinbei Electrician Hengyang Cable Co., Ltd. The composite optical fiber overhead ground wire can adopt the conventional composite optical fiber overhead ground wire produced by China Jiangsu Tongguang Optical Cable Co., Ltd.

The lightning protection insulator is used to suspend the conductor, so that it has the functions of suspension, insulation and lightning protection at the same time. When the lightning strikes the tower or the conductor directly, the lightning overvoltage will make the lightning protection insulator act, absorb the impact energy, and protect the overvoltage It acts as a clamp, thereby protecting the entire insulator from flashover, avoiding tripping accidents of transmission lines, and improving power supply reliability. The composite optical fiber overhead ground wire is directly installed at the waist of the tower body, under the three-phase wire, which can not only realize the normal power communication function, but also reduce the lightning overvoltage on the lightning protection insulator due to the coupling effect, and further improve the lightning resistance level , effectively reduce the number of lightning trips on the transmission line, and improve the reliability of power supply.

The composite optical fiber overhead ground wire is directly installed at the waist of the iron tower body, canceling the ground wire support and a common overhead ground wire at the top of the existing technology tower, saving material and manpower, and eliminating the need for two overhead ground wires in the prior art. Loop loss; the mechanical strength of the tower body is much greater than the strength of the ground wire support, which greatly improves the ice resistance of the composite optical fiber overhead ground wire, thereby improving the ice resistance of the transmission line as a whole and further improving the reliability of power supply. The installation position of the composite optical fiber overhead ground wire is also convenient for maintenance.

Claims (2)

1. An iron tower of an AC transmission line, comprising a tower body and a cross arm at its top, a composite optical fiber overhead ground wire is installed on the tower body, insulators are respectively connected to the two ends and the middle part of the lower side of the cross arm, and the lower ends of the insulators at both ends are respectively The side-phase wires are connected, and the lower end of the middle insulator is connected to the middle-phase wire, and the feature is that the insulator is a lightning protection insulator. 2. The AC transmission line iron tower according to claim 1, wherein the composite optical fiber overhead ground wire is installed at the waist of the tower body.