Simulation Study on Arc Characteristics of Single Phase Grounding Overhead Line Tree in Distribution Network

In response to forest fires caused by single-phase grounding of distribution lines, this paper establishes a mathematical model of single-phase grounding overhead line tree arc in distribution networks based on the theory of magnetic fluid dynamics. The effects of arc length and residual current size on arc characteristics are studied. The simulation results show that under stable arc ignition, the gap distance increases from 4cm to 20cm at the peak of arc voltage, resulting in a decrease in the center temperature of the arc column from 8600K to 7000K, And the peak value of stable arc voltage increases with the increase of arc length and arc radius; The zero crossing arc resistance of the arc current reaches its maximum value, and the arc resistance increases with the increase of arc length and radius. Under the same spacing, the larger the compensation current, the higher the arc temperature, the less likely it is to extinguish the arc, and the lower the arc resistance; When the residual current is 10A, the wind speed reaches 9m/s, and the arc extinguishing time is before the first zero crossing point of the current. The research results can further provide theoretical reference for automatic tuning of suppression coils, residual current setting, and arc extinguishing characteristics.