The physical processes of power interruption and their modelling

Arc research, especially since late sixties, has made enormous progress. We now understand and can describe quantitatively the fundamental processes occurring in an arc. The behaviour of an arc in an axial gas blast can be quantitatively predicted. However, for certain operational conditions of puffer breakers, rotary and auto-expansion breakers further work needs to be done. This is due to the complexity of the interaction of an arc with its surroundings, the 3-dimensional nature of the problem, a lack of fundamental data (atomic and molecular), a moving boundary etc. However, these problems will be overcome especially in view of the rapid advancement in computing power. The identification of the above processes and their mathematical modelling form the subject matter of this paper. Discussion is confined to axially blown arcs for which limited test results are available for comparison with theory