3D time-dependent model and simulation of high-current vacuum arc in commercial axial magnetic fields vacuum interrupters

摘要

Based on quasi-steady three-dimensional (3D) model, time-dependent axial magnetic field vacuum arcs (AMFVAs) characteristics in commercial vacuum interrupters for half-wave interruption of power-frequency (50 Hz) current are simulated. 3D spatial distributions of many important plasma parameters and electric characteristics in AMFVAs can be obtained, such as ion number density, ion temperature, electron temperature, plasma pressure, current densities along different directions (x, y and z), electric fields strength along different directions, and so on. Simulation results show that there exist significant spiral-shaped rotational phenomena in the AMFVAs. In current time-dependent simulation, the influence of AMF lagged from arc current is considered in the arc model. Simulation results show that the rotational velocity of vacuum arc plasma at later 1/4 wave is much larger than that at forward 1/4 wave, especially for 8 ms, 9 ms and near to current-zero moments. This kind of plasma rotational phenomena also can be observed by high-speed arc photographs.