Improved modelling of corona for surge propagation studies

A previously developed physical corona model is improved by introducing the streamer extinction field as a simulation parameter. In the model used to reproduce experimental charge-voltage curves, for different surge polarity, conductor radius and weather conditions, the values of the streamer extinction electric field employed in the simulation are found to match those measured in laboratory tests. The simulation model is used to investigate the changes that can be observed on the charge-voltage diagrams as a surge is attenuated and distorted along propagation. Therefore, it is proven that computation of surge propagation taking corona into account should be conducted as an interactive process. Indeed, the shape of the charge-voltage curve stipulates the deformation of the surge, the shape of the charge-voltage curve being itself dependent on the surge waveshape