An original setup to measure grounding resistances using fast impulse currents and very short leads

•Grounding resistance measurement using fast impulse current and very short leads.•Analysis of the transient and steady state behavior of grounding grids.•Impact of transient behavior of measurement auxiliary circuit on grounding resistance measurements.•Use of a vertical LIA for current injection in grounding resistance measurement. This paper presents a method for measuring grounding resistances, which is based on the use of fast impulse current and short leads on the auxiliary measurement circuits. Usually, the conductor length of the voltage and current circuits used in grounding resistance measurements may be quite long depending on the grounding characteristics. Using the technique proposed in this paper, measurements are performed using short cable in the potential circuit and short wires, cable or LIA (Portuguese acronym to Artificial Infinite Line), in the current circuit. The proposed technique is evaluated by comparisons with measurement results using classical techniques and also through numerical simulations.