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CN-121983931-A - Circuit self-arc-extinguishing lightning protection device capable of releasing lightning current

CN121983931ACN 121983931 ACN121983931 ACN 121983931ACN-121983931-A

Abstract

The invention relates to the technical field of lightning protection and extinction, in particular to a line self-extinction lightning protection device capable of releasing lightning current, which comprises a main gap, an auxiliary gap, a nonlinear current limiting element, an inductor and a grounding resistor, wherein the main gap is arranged between the main gap and the auxiliary gap; the device not only utilizes a serial air gap to cut off the power frequency voltage stress of a zinc oxide valve plate and thoroughly solves the problem of easy aging of the traditional arrester valve plate, but also promotes the release efficiency of lightning stroke current through a cooperative mechanism of dual-channel leakage and inductance triggering of the main gap and the auxiliary gap, and simultaneously realizes the power frequency follow current by virtue of the design of high-resistance current limiting and gas generating material auxiliary arc quenching of the nonlinear element.

Inventors

  • BEI JIAPENG
  • WANG YONG
  • LIN JINSHAN
  • WANG ZHAORONG
  • LIN YUMING
  • LI PINGSONG
  • WU FUMEI
  • CHEN TIANYU
  • JIN ZHENGWEI
  • Cai Dezhuang

Assignees

  • 海南电网有限责任公司海口供电局

Dates

Publication Date
20260505
Application Date
20251219

Claims (10)

  1. 1. A circuit self-extinguishing lightning protection device capable of releasing lightning current is characterized in that: The device comprises a main gap (1), an auxiliary gap (2), a nonlinear current limiting element (3), an inductor (5) and a grounding resistor (4); one end of the main gap (1) is connected with a high-voltage line, and the other end of the main gap is connected with one end of the auxiliary gap (2) and one end of the nonlinear current limiting element (3) in parallel; The other end of the nonlinear current limiting element (3) is connected with one end of the inductor (5) in series; the other end of the auxiliary gap (2) and the other end of the inductor (5) are commonly connected with one end of the grounding resistor (4), and the other end of the grounding resistor (4) is grounded.
  2. 2. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 1, characterized in that the main gap (1) is a fixed air gap with a breakdown voltage lower than the flashover voltage of the protected line insulator (71).
  3. 3. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 2, wherein the nonlinear current limiting element (3) is a metal oxide element and has nonlinear volt-ampere characteristics of low resistance under lightning current and high resistance under power frequency current.
  4. 4. A line self-extinguishing lightning protection device capable of releasing a lightning strike current according to claim 3, characterized in that said inductance (5) is connected in series with said nonlinear current limiting element (3) for generating a counter potential to trigger the breakdown of said auxiliary gap (2) when a lightning passes.
  5. 5. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 4, further comprising a high-voltage connecting wire clamp (6), wherein one end of the high-voltage connecting wire clamp (6) is clamped on the high-voltage line, and the other end of the high-voltage connecting wire clamp is connected with one end of the main gap (1) through a connecting cable.
  6. 6. The line self-extinguishing lightning protection device capable of releasing lightning strike current according to claim 5, further comprising a mechanical fixing assembly (7), wherein the mechanical fixing assembly (7) comprises an insulator (71), a square cushion block (72) and a hook bolt (73), the insulator (71) is used for supporting a mounting structure of the main gap (1) and the auxiliary gap (2), and the hook bolt (73) is used for fixing the insulator (71) to a pole tower through the square cushion block (72).
  7. 7. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 6, wherein the auxiliary gap (2) and the main gap (1) form a parallel drainage channel, and the auxiliary gap (2) breaks down under the action of lightning current and breaks down under the action of power frequency freewheel.
  8. 8. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 7, wherein the nonlinear current limiting element (3) is arranged to face the rapid increase of the power frequency freewheel resistance to be close to an insulator state, and the power frequency freewheel is forcedly limited to be less than tens of milliamperes, so that the electric arc cannot be maintained and extinguished.
  9. 9. The line self-extinguishing lightning protection device capable of releasing lightning current according to claim 8, wherein the main gap (1) is in an off state during normal operation, and the nonlinear current limiting element (3), the inductor (5) and the high-voltage line are isolated.
  10. 10. The line self-extinguishing lightning protection device capable of releasing lightning strike current according to claim 9, wherein the grounding resistor (4) is connected between the auxiliary gap (2), the common end of the inductor (5) and the ground for guiding the lightning strike current to the ground.

Description

Circuit self-arc-extinguishing lightning protection device capable of releasing lightning current Technical Field The invention relates to the technical field of lightning protection and extinction, in particular to a line self-extinction lightning protection device capable of releasing lightning current. Background The 10kV distribution network overhead line is the line which is most closely connected with a user, and the current conditions of tripping, wire breakage, even damage of line equipment and the like caused by lightning strike occur. Therefore, the lightning protection of the distribution network line directly influences the power supply reliability, and the conventional means for installing the lightning arrester is currently used for the distribution network line. Conventional zinc oxide arresters are typically composed of zinc oxide sheets that are reliably connected to the tower ground grid by down-lead wires. When lightning overvoltage occurs, the zinc oxide valve plate is conducted, and overvoltage energy is discharged into the ground through the grounding grid, so that insulation of circuit equipment is protected. The zinc oxide lightning arrester realizes voltage limiting by means of the nonlinear volt-ampere characteristic of the valve plate. The zinc oxide valve plate of the traditional zinc oxide lightning arrester is easy to age under the combined action of factors such as multiple lightning strike impact, power frequency leakage current heating, moisture invasion and the like, and is characterized by action voltage rise, residual voltage increase, leakage current increase and the like. After long-term operation, even if the appearance is perfect, the internal electrical performance is obviously aged, the protection capability of the circuit is difficult to ensure, and the damage probability is extremely high even when the circuit is subjected to strong direct impact Lei Shi. Therefore, the metal oxide lightning arrester with the external series gap, which is provided with the air gap fixed in series, is adopted in the circuit to solve the aging problem of the zinc oxide valve plate, and when the circuit of the lightning arrester is normal, the air gap isolates the lightning arrester body from the high-voltage circuit, so that the lightning arrester body is not subjected to power frequency operation voltage, and the aging of the zinc oxide valve plate is reduced. When lightning overvoltage comes, the air gap breaks down in preference to line insulation, lightning current is led to the lightning arrester body, metal oxide resistor (MOA) in the lightning arrester instantaneously changes into a low-resistance state, overvoltage is clamped at a safe level (residual voltage) and discharged to the ground, and line insulation is protected. After lightning current passes, the resistor sheet restores to a high resistance state, the power frequency follow current is forcibly cut off, the gap arc is extinguished, insulation is restored, and the device is automatically reset. Disclosure of Invention The invention aims to provide a line self-extinguishing lightning protection device capable of releasing lightning current, which aims to solve the problems of The technical scheme is that the circuit self-extinguishing lightning protection device capable of releasing lightning current comprises a main gap, an auxiliary gap, a nonlinear current limiting element, an inductor and a grounding resistor; one end of the main gap is connected with a high-voltage line, and the other end of the main gap is connected with one end of the auxiliary gap and one end of the nonlinear current limiting element in parallel; The other end of the nonlinear current limiting element is connected with one end of the inductor in series; the other end of the auxiliary gap and the other end of the inductor are commonly connected with one end of the grounding resistor, and the other end of the grounding resistor is grounded. In a preferable scheme of the line self-extinguishing lightning protection device capable of releasing lightning current, the main gap is a fixed air gap, and the breakdown voltage of the main gap is lower than the flashover voltage of an insulator of a protected line. In a preferable scheme of the line self-extinguishing lightning protection device capable of releasing lightning current, the nonlinear current limiting element is a metal oxide element and has the nonlinear volt-ampere characteristics of low resistance under lightning current and high resistance under power frequency current. In a preferred scheme of the line self-extinguishing lightning protection device capable of releasing lightning strike current, the inductor is connected in series with the nonlinear current limiting element and is used for generating reverse potential to trigger the auxiliary gap to break down when lightning passes through. In a preferable scheme of the line self-extinguishing lightning protection device capable of rel