Use of the singly ionised silicon lines broadening for the evaluation of the arc plasma pressure during HBC fuse operation
Résumé
During the High Breaking Capacity fuse operation, the main part of the electric energy brought by the fault current is dissipated towards the granular sand whose role is very complex to understand. The arc plasma confinement due to the granular filler makes more difficult the evaluation of the plasma physical properties, especially the pressure inside the arc channel. A specific device has been designed to investigate the effect of the pressure and the electric power on the ionised silicon line broadening. From the measurements, the broadening is expressed in the form of a specific broadening coefficient defined per pressure unit and electric power unit for the multiplets Si II (1) (2) (3). These coefficients are used to give an estimation of the pressure of about 3.0 MPa for the observed maximum pressure inside the arc channel.