Study of the Long-Time Arcing Characteristics of SF6 in a ±800KV High Speed Switch

With the growing capacity of DC transmission systems, switch with the abilities of interruption have been requested more strictly. High speed switch (HSS) is a new type of switch equipment that has received widespread attention in the world. However, the research on the arc extinguishing chamber of HSS during arcing is still in its infancy. Therefore, the paper carries out the arcing simulation to study the long-time (400ms) arcing characteristics, around the core problem of optimization of extinguishing chamber structure. In this paper, firstly, based on the magneto-hydro-dynamic (MHD) modeling method, the 2-D model of arc burning process is established for the structure of a ±800KV HSS, considering the high-speed dynamic motion process of the contact. Secondly, According to real gas model, the actual gas attributes of SF6 are loaded into the governing equations for calculation. Then, focusing on the dynamic temporal and spatial distribution of long-time arc burning, we can analyze the influence of arc energy on pressure and temperature. The results about the distribution law of arc energy and temperature, pressure and gas flow are calculated for the evaluation of the performance of arc burning. The simulation results are in agree with the actual physical principle. The established model in this thesis is valid and simulation results are expected to enrich the understanding of the long-time arcing characteristics. The work of this paper is significant and can provide a theoretical basis and technical guidance for engineering application in the high speed switch.