Modelling and simulation of the grounding system of a class of power transmission line towers involving inhomogeneous conductive media

•Low frequency currents in an inhomogeneous medium.•Simulation of the complex grounding system of a transmission tower.•Impact of the tower structural elements on grounding resistance.•The best electrode configuration to reduce and smooth the ground potential.

The grounding system of a class of power transmission line towers involving inhomogeneous conductive media is modelled in order to simulate its behaviour in case that a current earth fault takes place. The simulation includes structural elements of the tower and provides an estimate of the grounding resistance of the tower, assuming that a standard grounding electrode is buried as the main part of the grounding installation. The effect of structural elements on grounding resistance is discussed and a quantitative estimate of this effect is evaluated.