Current Zero Deformation by Interaction of the Air Blast Arc with the Test Circuit

Interaction of the gas blast arc with the electrical network causes a deformation in the waveshapes of the arc current and voltage around the current zero region. The deformation can help the arc make the transition from the conducting to the non-conducting state before a high reverse voltage appears across it. The contribution of shunt resistance and capacitance to the deformation is investigated for an air blast arc in a test circuit. The time dependence of the arc conductance is obtained from a model that incorporates the energy balance equation and the details of the axial profile of the arc. The roles of the shunting elements in determining the RRRV across the arc and its ability to withstand it are explored. The time dependence of arc parameters around current zero is also investigated.