A STUDY ON THE USE OF BARE BURIED CONDUCTORS IN AN EXTENDED INTERCONNECTION OF EARTHING SYSTEMS INSIDE A MV NETWORK

In the field of electrical safety an important topic is the transmission of voltages, during an earth fault, inside an extended interconnection of local earthing systems. The paper presents a study, with reference to the MV networks, about those systems where the interconnection between the earth electrodes of the electrical installations is carried out using bare buried conductors. Starting from the description of the circuital model of a bare buried conductor interconnecting together the earth electrodes of two MV/lv substations, the mathematical model of the whole interconnected earthing system is found. Finally, the results of some simulations, giving the distribution of the fault current between the interconnected earth electrodes and the bare buried conductors, are shown.