Impulse Impedance Measurement Methodology in Space Restricted Locations

This paper presents the analysis results of field measurements of ground resistance and impulse impedance. First, the Current Derivative Method is presented, whose objective is to obtain the RLF steady-state ground resistance value from the transient impedance curve $Z(t)$. Second, it is presented a study about the application of ground resistance measurement methods, for electrodes positioned at reduced distances, in impedance measurements under the same conditions, and it is concluded that these methods do not present satisfactory results. Based on the results, a proposal is presented for the development of a method with orthogonally positioned electrodes that allows field measurements without significant errors, both for ground resistance and for impulse impedance.