Spatiotemporal evolution of short-circuit arc to secondary arc based on the improved charge model

The initial shape of the secondary arc considerably influences its subsequent shape. To establish the model for the arcing time of the secondary arc and modify the single-phase reclosing sequence, theoretically and experimentally analyzing the evolution process of the short-circuit arc to the secondary arc is critical. In this study, an improved charge simulation method was used to develop the internal space electric field model of the short-circuit arc. The intensity of the electric field was used as an independent variable to describe the initial shape of the secondary arc. A secondary arc evolution model was developed based on this model. Moreover, the accuracy of the model was evaluated by comparing with physical experimental results. When the secondary arc current increased, the arcing time and dispersion increased. There is an overall trend of increasing arc length with increasing arcing time. Nevertheless, there is a reduction in arc length during arc ignition due to short circuits between the arc columns. Furthermore, the arcing time decreased in the range of 0°–90° as the angle between the wind direction and the x-axis increased. This study investigated the method by which short-circuit arcs evolve into secondary arcs. The results can be used to develop the secondary arc evolution model and provide both a technical and theoretical basis for secondary arc suppression.