Soil ionization is important for several engineering applications since when occurring dominates the impulse behavior of grounding systems. Thus, knowledge on electrical discharge characteristics developing in soil is essential; their accurate determination is performed experimentally due to the complex physical mechanisms involved and the widely varying soil properties and conditions. This work introduces a methodology for processing and analyzing the associated measured impulse voltage and current waveforms. Time instants related to soil ionization phenomena are identified along with current, voltage and impedance values. Characteristic curves are constructed in order to evaluate the dynamics of soil ionization growth. The recorded impulse waveforms are processed automatically using a code written in MATLAB software. Preliminary results for a wet sandy soil are presented and discussed.

Electrical discharges,Grounding,Impulse impedance,Lightning impulse voltages,Soil ionization