冲击电弧自截断机理及对建弧率影响

Mechanism on Shock Arc Self-truncation And Impact on Arc-establishing Rate

为了解决架空输电线路雷电防护的问题,研究了一种冲击电弧自截断的防雷保护方法。这种方法是通过绝缘配合将雷电流引入到防雷保护间隙中发生冲击闪络,利用雷电流产生的感应电流同步触发冲击气流发生器产生高速纵吹气流熄灭电弧,实现冲击电弧自截断。从电弧能量平衡的角度分析了冲击电弧自截断原理。进行了实验室模拟雷击的试验对灭弧的可靠性进行了验证,试验结果表面冲击电弧自截断的防雷保护装置能够快速有效熄灭电弧,灭弧时间为3.8ms,大幅降低了建弧率,使得冲击闪络几乎无法转化为稳定的工频电弧。

In order to solve the problem of overhead transmission line lightning protection,we developed a kind of lightning protection method based on shock arc self-truncation. Though insulation coordination,lightning current will be introduced to the lightning protection gap. Then impulse flashover occurred in the gap,and induced current produced by lightning current emerged at the same time. High-speed longitudinal blow airstream triggered by lightning current could interrupt subsequent power frequency arc rapidly,and realize the result of shock arc self-truncation. From the angle of the arc energy balance,we analyzed the principle of shock arc self-truncation. Then we conducted the arc-extinguishing tests to verify it＇s reliability. The results indicate that the lightning protection device could extinguish arc quickly and effectively and substantially lower the arc-establishing rate. Arc-extinguishing time is 3. 8ms.