Analysis of methods to reduce the ground resistance of transmission line towers

Successful and reliable operation of entire power systems depends to a considerable extent on the appropriate earthing of transmission line towers. In case of unfavorable but unavoidable geological conditions it is a responsible task to keep the resistance to earth and also touch and step voltages under an acceptable level. Different arrangements of auxiliary grounding electrodes and backfills are offered to solve the problem by reducing the resistance to earth. The auxiliary electrodes can connect the towers beneath or over the soil surface, and can be applied in case of a single tower grounding as well. Detailed computer simulation studies have been carried out to evaluate the efficiency of some type of these solutions.