直流接地极线路招弧角间电弧的运动模型

Motion Model of Arc between Arcing Horns in DC Grounding Electrode Line

摘要:

针对直流接地极线路在遭受雷击和操作过电压时容易在绝缘子串间建立起电弧的问题，采用链式电弧模型， 考虑电流元受磁场力、热浮力和空气阻力的作用以及电流元在不同运动速度下空气阻力系数与雷诺数之间的关系， 分析电流元的受力，得出电弧的运动模型。通过仿真分析直流电弧在羊角型电极间的运动过程，发现直流电弧的熄 弧时间与电流大小、电极张角之间存在相关关系，电弧电流和电极张角越大，直流电弧的熄弧时间越短。仿真研究结 果为后续进行直流电弧试验提供理论依据。

Abstract:

Aiming at the problem that DC grounding electrode line is easy to build arc between insulator strings when subjected to lightning stroke and operating overvoltage，the chain arc model is adopted to consider the effect of magnetic field force，thermal buoyancy and air resistance on current element，and the relationship between air resistance coefficient and Reynolds number under different moving speeds of current element． The force of current element is analyzed and the motion model of arc is obtained． Through simulation and analysis of the movement of DC arc between sheep － horn electrodes，it is found that there is a correlation between the extinguishing time of DC arc and the magnitude of current and electrode opening angles． The bigger the arc current and the electrode opening angle，the shorter the extinguishing time of DC arc． The simulation research provides a theoretical basis for the subsequent DC arc test．