Simulation analysis on transient characteristics of high-current vacuum arc in process of interruption

For the traditional steady state model cannot characterize the dynamic characteristics of the vacuum arc in the process of interruption, the high current vacuum arc with breaking peak of 10 kA under power frequency current was taken as the research object, a two-dimensional physical model of the arc column region of the vacuum arc plasma was built. The time-varying terms of flow field parameters such as density, temperature, pressure and velocity were introduced into the existing two-temperature magneto-hydrodynamic steady-state model. And the dynamic grid technology was used to simulate the opening process of contact. Considering the changes of physical field parameters under the change of current and opening distance, the transient characteristics of arc micro flow field was obtained in the process of interruption, and the mode and energy change of arc was explored in the process of interruption. The analysis results show that the ion pressure, temperature, electron temperature and anode surface energy flux density all decrease with the separation of the moving and static contacts; the ion velocity does not change significantly; the plasma continues to diffuse outward, and the metal vapor source also gradually decreases, the plasma density between the electrodes decreases, the anode has not yet reached the active level, and finally the arc is extinguished. © 2024 Editorial Department of Electric Machines and Control. All rights reserved.