CN103812007A - Band gap puffer type medium voltage lightning arrester for overhead distribution line - Google Patents

Abstract

The invention relates to a band gap puffer type medium voltage lightning arrester for an overhead distribution line, belonging to the technical field of an electric power facility element. The low-voltage part of the band gap puffer type medium voltage lightning arrester is connected with the low-voltage end of either the tower or the insulator of the overhead distribution line through a connecting base, and the high-voltage part of the band gap puffer type medium voltage lightning arrester is fixed on the overhead distribution line through a connecting support; the low-voltage part consists of a metal base and an insulating sleeve, wherein the lower end of the metal base is provided with a connecting base, a plurality of cavity electrodes and a plurality of arc extinguish chambers are sequentially and intermittently arranged in the insulation sleeve, blowholes for spraying high-speed gas are formed in the top of the extinguish chambers, and a low-voltage electrode is formed in the top of the insulating sleeve; the upper half part of the low-voltage part is exposed, a discharging gap is jointly formed by the low-voltage electrode and the high-voltage electrode, the high-voltage part consists of a high-voltage electrode and a connecting support, and a conductor grip is jointly formed by the high-voltage electrode and the connecting support. The lightning arrester provided by the invention is simple in structure, convenient to mount, definite in function, is capable of effectively cutting off discharging arc caused by the overvoltage of a circuit, and guaranteeing the reliability of a power system.

Description

A medium-voltage lightning arrester with gap blowing arc for overhead distribution lines

technical field

The invention relates to a medium-voltage arc-blowing arrester with a gap for overhead power distribution lines, which belongs to the technical field of power facility components.

Background technique

Installing surge arresters with series gaps on overhead distribution lines can effectively discharge overvoltage and protect insulator strings from burning by discharge arcs when the lines are struck by lightning or insulator strings flashover. Ordinary surge arresters with series gaps can effectively absorb the overvoltage on the line, break down the air gap, and guide the overvoltage to the ground. However, it does not have the ability to actively extinguish the arc, and cannot automatically extinguish the power-frequency freewheeling arc caused by the breakdown of the air gap. Only when it is used in conjunction with an automatic reclosing device can a better lightning protection effect be obtained. However, due to the need to wait for the circuit breaker to operate, it takes a long time to extinguish the arc on the series gap. Every time the overvoltage on the line is released to the ground, it may cause the metal fittings to be burned by the arc, or even burn the wire in severe cases.

Contents of the invention

The purpose of the present invention is to propose a medium-voltage surge arrester with a gap blowing arc for overhead distribution lines, to solve the problem in the prior art that it cannot automatically extinguish the power-frequency freewheeling arc, and to use high-speed gas to blow off the arc, To effectively cut off the discharge arc caused by the overvoltage of the line, to ensure the reliability and safety of the transmission line of the power system.

The arc blowing medium voltage surge arrester with gaps for overhead distribution lines proposed by the present invention includes a low-voltage part and a high-voltage part, the low-voltage part is connected to the low-voltage end of the pole tower or insulator of the overhead power distribution line through the connecting base, and the high-voltage part is connected through the connecting bracket Fixed on the overhead power distribution line; the low-voltage part is composed of a metal base and an insulating sleeve. The upper end of the metal base is connected to the insulating sleeve in a hook shape. The lower end of the connecting base is the connection base, which is in the shape of a wire clip. There are multiple chamber electrodes and multiple arc extinguishing chambers arranged at intervals in the insulating sleeve. The top of the low-voltage electrode is a low-voltage electrode, the lower half of the low-voltage electrode is covered by an insulating layer, and the upper half of the low-voltage electrode is exposed, forming a discharge gap with the high-voltage electrode. The high-voltage part is composed of a high-voltage electrode and a connecting bracket. The bracket is relatively fixed, and the high-voltage electrode and the connecting bracket together become a wire clip.

The arc-blowing medium-voltage surge arrester with gaps for overhead distribution lines proposed by the present invention has the advantage that, compared with the existing surge arresters with series gaps, the arc-blowing medium-voltage surge arresters with gaps of the present invention can be used in each The high-speed airflow generated by the high temperature in an arc extinguishing chamber cuts off the small arc in the arc extinguishing chamber to automatically cut off the large arc. The low-voltage part of the arrester is connected to the low-voltage side of the insulator of the transmission line tower, and the top is separated by an air gap, which avoids the long-term power frequency voltage at both ends of the arrester, prevents the rapid aging of the arrester, and reduces the leakage current. The surge arrester located on the low-voltage side is convenient for maintenance during operation. The high-voltage electrode of the arrester can lead the arc root from the wire to the high-voltage electrode, and can effectively prevent the high temperature of the arc root from burning the wire during the arc extinguishing action, thereby preventing the occurrence of disconnection accidents. The lightning arrester of the invention has simple structure, convenient installation and clear functions, can effectively cut off the discharge arc caused by the overvoltage of the line, and ensures the reliability of the power system.

Description of drawings

Fig. 1 is a structural schematic diagram of the medium and low voltage part of the medium voltage surge arrester with a gap for overhead distribution lines proposed by the present invention.

Fig. 2 is a structural schematic diagram of the high-voltage part of the arc-blowing arrester with a gap of the present invention.

In Figure 1 and Figure 2, 1 is the metal base, 2 is the insulating sleeve, 3 is the connection base, 4 is the chamber electrode, 5 is the arc extinguishing chamber, 6 is the jet hole, 7 is the low voltage electrode, 8 is the high voltage electrode, 9 is a connecting bracket.

Detailed ways

The arc blowing medium-voltage surge arrester with gaps for overhead power distribution lines proposed by the present invention has a structure as shown in Figure 1, including a low-voltage part and a high-voltage part, and the low-voltage part passes through the tower or insulator connecting the base 3 and the overhead power distribution line The low-voltage side is connected, and the high-voltage part is fixed on the overhead power distribution line through the connecting bracket 9. The low-voltage part is composed of a metal base 1 and an insulating sleeve 2. The upper end of the metal base 1 is connected to the insulating sleeve 2 in a hook shape, the upper end of the metal base 1 is wrapped by the insulating sleeve 2, and the lower end of the metal base 1 is connected. The base is connected to the base 3 in the shape of a wire clamp. A plurality of chamber electrodes 4 and a plurality of arc extinguishing chambers 5 are sequentially arranged in the insulating sleeve 2 at intervals. The top of the arc extinguishing chamber 5 is provided with a jet hole 6 for high-speed gas injection, and the top of the insulating sleeve 2 is a low-voltage electrode 7. , the lower half of the low-voltage electrode 7 is wrapped by the insulating layer 2, and the upper half of the low-voltage electrode 7 is exposed, forming a discharge gap together with the high-voltage electrode 8. The high-voltage part consists of a high-voltage electrode 8 and a connecting bracket 9. The high-voltage electrode 8 and the connecting bracket 9 are relatively fixed. The high-voltage electrode 8 and the connecting bracket 9 together form a wire clamp, as shown in FIG. 2 .

The arc-blowing medium-voltage surge arrester with gaps for overhead power distribution lines proposed by the present invention uses the low-voltage electrodes on the top of the arc-blowing arrester to guide the arc into the arc extinguishing chamber of the arrester, and generates high temperature through the discharge of the chamber electrodes in the arc extinguishing chamber. The air is heated, and the released high-speed gas cuts off the arc, achieving the function of automatic arc extinguishing of the arrester.

In the arc-blowing medium-voltage arrester with gaps of the present invention, when an overvoltage occurs in the line, the overvoltage causes the high-voltage electrode 8 and the low-voltage electrode 7 at the end to discharge to generate a large arc, and the arc-blowing arrester uses the low-voltage electrode 7 at the end to discharge the arc on the line. The overvoltage is led from the high-voltage electrode to the arc extinguishing chamber of the arrester, and the chamber electrode 4 discharges to generate a small telephone arc, and the high-temperature arc heats the air in the arc extinguishing chamber 5, causing the air to expand and eject rapidly from the jet hole 6 . The jetted high-speed gas blows out the high-energy ions that can form a stable arc in the arc extinguishing chamber 5, cutting off the arc to achieve the effect of self-extinguishing the arc.

Claims (1)

1. A medium-voltage arc-blowing arrester with a gap for overhead distribution lines, characterized in that the arc-blowing medium-voltage arrester with a gap includes a low-voltage part and a high-voltage part, and the low-voltage part passes through the connecting base and the overhead distribution line. The low-voltage end of the tower or insulator is connected, and the high-voltage part is fixed on the overhead distribution line through the connecting bracket; the low-voltage part is composed of a metal base and an insulating sleeve, and the upper end of the metal base is hooked after being connected with the insulating sleeve. The upper end of the base is wrapped by an insulating sleeve, the lower end of the metal base is a connection base, and the connection base is in the shape of a wire clip. There are multiple chamber electrodes and multiple arc extinguishing chambers arranged at intervals in the insulating sleeve, and the top of the arc extinguishing chamber is opened. There are jet holes for high-speed gas injection, the top of the insulating sleeve is a low-voltage electrode, the lower half of the low-voltage electrode is wrapped by an insulating layer, and the upper half of the low-voltage electrode is exposed, forming a discharge gap together with the high-voltage electrode. The high-voltage part It consists of a high-voltage electrode and a connecting bracket, the high-voltage electrode and the connecting bracket are relatively fixed, and the high-voltage electrode and the connecting bracket together become a wire clamp.

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