Research of arc extinguishing characteristics of annular multi-break compression lightning protection devices

The plasma arc generated by lightning strikes is the primary factor causing short circuits in transmission lines. To reduce the lightning-induced trip-out rate of transmission lines, this paper proposes a novel annular multi-break compression active arc-extinguishing device. This device utilizes a specially designed internal structure to elongate the arc, forming multiple unstable small arc segments. It then employs the expanding gas flow generated by the arc's Joule heat to forcibly blow out the flashover arc, thereby achieving rapid arc extinction. Based on magnetohydrodynamic theory, this paper establishes a mathematical model of plasma arcs and their energy balance equations under the influence of airflow, and a two-dimensional geometric model of the arc-extinguishing device was established by using COMSOL Multiphysics simulation software to analyze the changes in plasma arc temperature and gas flow velocity during the arc-extinguishing process. The simulation results demonstrate that the device can extinguish the arc within 900 ms without reignition. Finally, high-current withstand tests were conducted. Test results show that the device can withstand high-current impacts and reduce the impulse current to zero within 15 ms, which further confirms its excellent lightning protection and arc-extinguishing performance.